fe-connect.c File Reference

#include "postgres_fe.h"
#include <sys/stat.h>
#include <fcntl.h>
#include <ctype.h>
#include <netdb.h>
#include <time.h>
#include <unistd.h>
#include "common/base64.h"
#include "common/ip.h"
#include "common/link-canary.h"
#include "common/scram-common.h"
#include "common/string.h"
#include "fe-auth.h"
#include "libpq-fe.h"
#include "libpq-int.h"
#include "mb/pg_wchar.h"
#include "pg_config_paths.h"
#include "port/pg_bswap.h"
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <pwd.h>
#include <pthread.h>

Include dependency graph for fe-connect.c:

Go to the source code of this file.

Data Structures
struct	_internalPQconninfoOption

Macros
#define	PGPASSFILE   ".pgpass"
#define	ERRCODE_APPNAME_UNKNOWN   "42704"
#define	ERRCODE_INVALID_PASSWORD   "28P01"
#define	ERRCODE_CANNOT_CONNECT_NOW   "57P03"
#define	DefaultHost   "localhost"
#define	DefaultOption   ""
#define	DefaultChannelBinding   "disable"
#define	DefaultTargetSessionAttrs   "any"
#define	DefaultLoadBalanceHosts   "disable"
#define	DefaultSSLMode   "disable"
#define	DefaultSSLCertMode   "disable"
#define	DefaultSSLNegotiation   "postgres"
#define	DefaultGSSMode   "disable"
#define	ENCRYPTION_NEGOTIATION_FAILED(msg)
#define	CONNECTION_FAILED()
#define	MAX_ERRLEN   30000
#define	SELECT_NEXT_METHOD(method)

Typedefs
typedef struct _internalPQconninfoOption	internalPQconninfoOption

Functions
static bool	connectOptions1 (PGconn *conn, const char *conninfo)
static bool	init_allowed_encryption_methods (PGconn *conn)
static bool	connection_failed (PGconn *conn)
static bool	select_next_encryption_method (PGconn *conn, bool have_valid_connection)
static PGPing	internal_ping (PGconn *conn)
static void	pqFreeCommandQueue (PGcmdQueueEntry *queue)
static bool	fillPGconn (PGconn *conn, PQconninfoOption *connOptions)
static void	freePGconn (PGconn *conn)
static void	release_conn_addrinfo (PGconn *conn)
static int	store_conn_addrinfo (PGconn *conn, struct addrinfo *addrlist)
static void	sendTerminateConn (PGconn *conn)
static PQconninfoOption *	conninfo_init (PQExpBuffer errorMessage)
static PQconninfoOption *	parse_connection_string (const char *connstr, PQExpBuffer errorMessage, bool use_defaults)
static int	uri_prefix_length (const char *connstr)
static bool	recognized_connection_string (const char *connstr)
static PQconninfoOption *	conninfo_parse (const char *conninfo, PQExpBuffer errorMessage, bool use_defaults)
static PQconninfoOption *	conninfo_array_parse (const char *const *keywords, const char *const *values, PQExpBuffer errorMessage, bool use_defaults, int expand_dbname)
static bool	conninfo_add_defaults (PQconninfoOption *options, PQExpBuffer errorMessage)
static PQconninfoOption *	conninfo_uri_parse (const char *uri, PQExpBuffer errorMessage, bool use_defaults)
static bool	conninfo_uri_parse_options (PQconninfoOption *options, const char *uri, PQExpBuffer errorMessage)
static bool	conninfo_uri_parse_params (char *params, PQconninfoOption *connOptions, PQExpBuffer errorMessage)
static char *	conninfo_uri_decode (const char *str, PQExpBuffer errorMessage)
static bool	get_hexdigit (char digit, int *value)
static const char *	conninfo_getval (PQconninfoOption *connOptions, const char *keyword)
static PQconninfoOption *	conninfo_storeval (PQconninfoOption *connOptions, const char *keyword, const char *value, PQExpBuffer errorMessage, bool ignoreMissing, bool uri_decode)
static PQconninfoOption *	conninfo_find (PQconninfoOption *connOptions, const char *keyword)
static void	defaultNoticeReceiver (void *arg, const PGresult *res)
static void	defaultNoticeProcessor (void *arg, const char *message)
static int	parseServiceInfo (PQconninfoOption *options, PQExpBuffer errorMessage)
static int	parseServiceFile (const char *serviceFile, const char *service, PQconninfoOption *options, PQExpBuffer errorMessage, bool *group_found)
static char *	pwdfMatchesString (char *buf, const char *token)
static char *	passwordFromFile (const char *hostname, const char *port, const char *dbname, const char *username, const char *pgpassfile)
static void	pgpassfileWarning (PGconn *conn)
static void	default_threadlock (int acquire)
static bool	sslVerifyProtocolVersion (const char *version)
static bool	sslVerifyProtocolRange (const char *min, const char *max)
void	pqDropConnection (PGconn *conn, bool flushInput)
static void	pqDropServerData (PGconn *conn)
PGconn *	PQconnectdbParams (const char *const *keywords, const char *const *values, int expand_dbname)
PGPing	PQpingParams (const char *const *keywords, const char *const *values, int expand_dbname)
PGconn *	PQconnectdb (const char *conninfo)
PGPing	PQping (const char *conninfo)
PGconn *	PQconnectStartParams (const char *const *keywords, const char *const *values, int expand_dbname)
PGconn *	PQconnectStart (const char *conninfo)
bool	pqCopyPGconn (PGconn *srcConn, PGconn *dstConn)
static int	count_comma_separated_elems (const char *input)
static char *	parse_comma_separated_list (char **startptr, bool *more)
static void	libpq_prng_init (PGconn *conn)
bool	pqConnectOptions2 (PGconn *conn)
PQconninfoOption *	PQconndefaults (void)
PGconn *	PQsetdbLogin (const char *pghost, const char *pgport, const char *pgoptions, const char *pgtty, const char *dbName, const char *login, const char *pwd)
static int	connectNoDelay (PGconn *conn)
static void	getHostaddr (PGconn *conn, char *host_addr, int host_addr_len)
static void	emitHostIdentityInfo (PGconn *conn, const char *host_addr)
static void	connectFailureMessage (PGconn *conn, int errorno)
static int	useKeepalives (PGconn *conn)
static int	setKeepalivesIdle (PGconn *conn)
static int	setKeepalivesInterval (PGconn *conn)
static int	setKeepalivesCount (PGconn *conn)
static int	setTCPUserTimeout (PGconn *conn)
int	pqConnectDBStart (PGconn *conn)
int	pqConnectDBComplete (PGconn *conn)
PostgresPollingStatusType	PQconnectPoll (PGconn *conn)
PGconn *	pqMakeEmptyPGconn (void)
void	pqReleaseConnHosts (PGconn *conn)
void	pqClosePGconn (PGconn *conn)
void	PQfinish (PGconn *conn)
void	PQreset (PGconn *conn)
int	PQresetStart (PGconn *conn)
PostgresPollingStatusType	PQresetPoll (PGconn *conn)
int	pqPacketSend (PGconn *conn, char pack_type, const void *buf, size_t buf_len)
PQconninfoOption *	PQconninfoParse (const char *conninfo, char **errmsg)
PQconninfoOption *	PQconninfo (PGconn *conn)
void	PQconninfoFree (PQconninfoOption *connOptions)
char *	PQdb (const PGconn *conn)
char *	PQservice (const PGconn *conn)
char *	PQuser (const PGconn *conn)
char *	PQpass (const PGconn *conn)
char *	PQhost (const PGconn *conn)
char *	PQhostaddr (const PGconn *conn)
char *	PQport (const PGconn *conn)
char *	PQtty (const PGconn *conn)
char *	PQoptions (const PGconn *conn)
ConnStatusType	PQstatus (const PGconn *conn)
PGTransactionStatusType	PQtransactionStatus (const PGconn *conn)
const char *	PQparameterStatus (const PGconn *conn, const char *paramName)
int	PQprotocolVersion (const PGconn *conn)
int	PQfullProtocolVersion (const PGconn *conn)
int	PQserverVersion (const PGconn *conn)
char *	PQerrorMessage (const PGconn *conn)
int	PQsocket (const PGconn *conn)
int	PQbackendPID (const PGconn *conn)
PGpipelineStatus	PQpipelineStatus (const PGconn *conn)
int	PQconnectionNeedsPassword (const PGconn *conn)
int	PQconnectionUsedPassword (const PGconn *conn)
int	PQconnectionUsedGSSAPI (const PGconn *conn)
int	PQclientEncoding (const PGconn *conn)
int	PQsetClientEncoding (PGconn *conn, const char *encoding)
PGVerbosity	PQsetErrorVerbosity (PGconn *conn, PGVerbosity verbosity)
PGContextVisibility	PQsetErrorContextVisibility (PGconn *conn, PGContextVisibility show_context)
PQnoticeReceiver	PQsetNoticeReceiver (PGconn *conn, PQnoticeReceiver proc, void *arg)
PQnoticeProcessor	PQsetNoticeProcessor (PGconn *conn, PQnoticeProcessor proc, void *arg)
bool	pqGetHomeDirectory (char *buf, int bufsize)
bool	pqParseIntParam (const char *value, int *result, PGconn *conn, const char *context)
pgthreadlock_t	PQregisterThreadLock (pgthreadlock_t newhandler)

Variables
static const internalPQconninfoOption	PQconninfoOptions []
static const PQEnvironmentOption	EnvironmentOptions []
static const char	uri_designator [] = "postgresql://"
static const char	short_uri_designator [] = "postgres://"
pgthreadlock_t	pg_g_threadlock = default_threadlock

Macro Definition Documentation

CONNECTION_FAILED

#define CONNECTION_FAILED

(

)

Value:

    do { \
        if (connection_failed(conn)) \
        { \
            need_new_connection = true; \
            goto keep_going; \
        } \
        else \
            goto error_return; \
    } while(0);

DefaultChannelBinding

#define DefaultChannelBinding   "disable"

Definition at line 123 of file fe-connect.c.

DefaultGSSMode

#define DefaultGSSMode   "disable"

Definition at line 139 of file fe-connect.c.

DefaultHost

#define DefaultHost   "localhost"

Definition at line 118 of file fe-connect.c.

DefaultLoadBalanceHosts

#define DefaultLoadBalanceHosts   "disable"

Definition at line 126 of file fe-connect.c.

DefaultOption

#define DefaultOption   ""

Definition at line 119 of file fe-connect.c.

DefaultSSLCertMode

#define DefaultSSLCertMode   "disable"

Definition at line 132 of file fe-connect.c.

DefaultSSLMode

#define DefaultSSLMode   "disable"

Definition at line 131 of file fe-connect.c.

DefaultSSLNegotiation

#define DefaultSSLNegotiation   "postgres"

Definition at line 134 of file fe-connect.c.

DefaultTargetSessionAttrs

#define DefaultTargetSessionAttrs   "any"

Definition at line 125 of file fe-connect.c.

ENCRYPTION_NEGOTIATION_FAILED

#define ENCRYPTION_NEGOTIATION_FAILED

(

msg

)

Value:

    do { \
        switch (encryption_negotiation_failed(conn)) \
        { \
            case 0: \
                libpq_append_conn_error(conn, (msg)); \
                goto error_return; \
            case 1: \
                conn->status = CONNECTION_MADE; \
                return PGRES_POLLING_WRITING; \
            case 2: \
                need_new_connection = true; \
                goto keep_going; \
        } \
    } while(0);

ERRCODE_APPNAME_UNKNOWN

#define ERRCODE_APPNAME_UNKNOWN   "42704"

Definition at line 88 of file fe-connect.c.

ERRCODE_CANNOT_CONNECT_NOW

#define ERRCODE_CANNOT_CONNECT_NOW   "57P03"

Definition at line 93 of file fe-connect.c.

ERRCODE_INVALID_PASSWORD

#define ERRCODE_INVALID_PASSWORD   "28P01"

Definition at line 91 of file fe-connect.c.

MAX_ERRLEN

#define MAX_ERRLEN   30000

PGPASSFILE

#define PGPASSFILE   ".pgpass"

Definition at line 77 of file fe-connect.c.

SELECT_NEXT_METHOD

#define SELECT_NEXT_METHOD

(

method

)

Value:

    do { \
        if ((remaining_methods & method) != 0) \
        { \
            conn->current_enc_method = method; \
            return true; \
        } \
    } while (false)

Typedef Documentation

internalPQconninfoOption

typedef struct _internalPQconninfoOption internalPQconninfoOption

Function Documentation

connectFailureMessage()

static void connectFailureMessage ( PGconn *  conn, int  errorno  )

static

Definition at line 2208 of file fe-connect.c.

{
    char        sebuf[PG_STRERROR_R_BUFLEN];
 
    appendPQExpBuffer(&conn->errorMessage,
                      "%s\n",
                      SOCK_STRERROR(errorno, sebuf, sizeof(sebuf)));
 
    if (conn->raddr.addr.ss_family == AF_UNIX)
        libpq_append_conn_error(conn, "\tIs the server running locally and accepting connections on that socket?");
    else
        libpq_append_conn_error(conn, "\tIs the server running on that host and accepting TCP/IP connections?");
}

References SockAddr::addr, appendPQExpBuffer(), conn, pg_conn::errorMessage, libpq_append_conn_error(), PG_STRERROR_R_BUFLEN, pg_conn::raddr, and SOCK_STRERROR.

Referenced by PQconnectPoll().

connection_failed()

static bool connection_failed ( PGconn *  conn )

static

Definition at line 4440 of file fe-connect.c.

{
    Assert((conn->failed_enc_methods & conn->current_enc_method) == 0);
    conn->failed_enc_methods |= conn->current_enc_method;
 
    return select_next_encryption_method(conn, false);
}

References Assert, conn, pg_conn::current_enc_method, pg_conn::failed_enc_methods, and select_next_encryption_method().

connectNoDelay()

static int connectNoDelay ( PGconn *  conn )

static

Definition at line 2093 of file fe-connect.c.

{
#ifdef  TCP_NODELAY
    int         on = 1;
 
    if (setsockopt(conn->sock, IPPROTO_TCP, TCP_NODELAY,
                   (char *) &on,
                   sizeof(on)) < 0)
    {
        char        sebuf[PG_STRERROR_R_BUFLEN];
 
        libpq_append_conn_error(conn, "could not set socket to TCP no delay mode: %s",
                                SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
        return 0;
    }
#endif
 
    return 1;
}

References conn, libpq_append_conn_error(), PG_STRERROR_R_BUFLEN, pg_conn::sock, SOCK_ERRNO, and SOCK_STRERROR.

Referenced by PQconnectPoll().

connectOptions1()

static bool connectOptions1 ( PGconn *  conn, const char *  conninfo  )

static

Definition at line 1006 of file fe-connect.c.

{
    PQconninfoOption *connOptions;
 
    /*
     * Parse the conninfo string
     */
    connOptions = parse_connection_string(conninfo, &conn->errorMessage, true);
    if (connOptions == NULL)
    {
        conn->status = CONNECTION_BAD;
        /* errorMessage is already set */
        return false;
    }
 
    /*
     * Move option values into conn structure
     */
    if (!fillPGconn(conn, connOptions))
    {
        conn->status = CONNECTION_BAD;
        PQconninfoFree(connOptions);
        return false;
    }
 
    /*
     * Free the option info - all is in conn now
     */
    PQconninfoFree(connOptions);
 
    return true;
}

References conn, CONNECTION_BAD, pg_conn::errorMessage, fillPGconn(), parse_connection_string(), PQconninfoFree(), and pg_conn::status.

Referenced by PQconnectStart(), and PQsetdbLogin().

conninfo_add_defaults()

static bool conninfo_add_defaults ( PQconninfoOption *  options, PQExpBuffer  errorMessage  )

static

Definition at line 6248 of file fe-connect.c.

{
    PQconninfoOption *option;
    PQconninfoOption *sslmode_default = NULL,
               *sslrootcert = NULL;
    char       *tmp;
 
    /*
     * If there's a service spec, use it to obtain any not-explicitly-given
     * parameters.  Ignore error if no error message buffer is passed because
     * there is no way to pass back the failure message.
     */
    if (parseServiceInfo(options, errorMessage) != 0 && errorMessage)
        return false;
 
    /*
     * Get the fallback resources for parameters not specified in the conninfo
     * string nor the service.
     */
    for (option = options; option->keyword != NULL; option++)
    {
        if (strcmp(option->keyword, "sslrootcert") == 0)
            sslrootcert = option;   /* save for later */
 
        if (option->val != NULL)
            continue;           /* Value was in conninfo or service */
 
        /*
         * Try to get the environment variable fallback
         */
        if (option->envvar != NULL)
        {
            if ((tmp = getenv(option->envvar)) != NULL)
            {
                option->val = strdup(tmp);
                if (!option->val)
                {
                    if (errorMessage)
                        libpq_append_error(errorMessage, "out of memory");
                    return false;
                }
                continue;
            }
        }
 
        /*
         * Interpret the deprecated PGREQUIRESSL environment variable.  Per
         * tradition, translate values starting with "1" to sslmode=require,
         * and ignore other values.  Given both PGREQUIRESSL=1 and PGSSLMODE,
         * PGSSLMODE takes precedence; the opposite was true before v9.3.
         */
        if (strcmp(option->keyword, "sslmode") == 0)
        {
            const char *requiresslenv = getenv("PGREQUIRESSL");
 
            if (requiresslenv != NULL && requiresslenv[0] == '1')
            {
                option->val = strdup("require");
                if (!option->val)
                {
                    if (errorMessage)
                        libpq_append_error(errorMessage, "out of memory");
                    return false;
                }
                continue;
            }
 
            /*
             * sslmode is not specified. Let it be filled in with the compiled
             * default for now, but if sslrootcert=system, we'll override the
             * default later before returning.
             */
            sslmode_default = option;
        }
 
        /*
         * No environment variable specified or the variable isn't set - try
         * compiled-in default
         */
        if (option->compiled != NULL)
        {
            option->val = strdup(option->compiled);
            if (!option->val)
            {
                if (errorMessage)
                    libpq_append_error(errorMessage, "out of memory");
                return false;
            }
            continue;
        }
 
        /*
         * Special handling for "user" option.  Note that if pg_fe_getauthname
         * fails, we just leave the value as NULL; there's no need for this to
         * be an error condition if the caller provides a user name.  The only
         * reason we do this now at all is so that callers of PQconndefaults
         * will see a correct default (barring error, of course).
         */
        if (strcmp(option->keyword, "user") == 0)
        {
            option->val = pg_fe_getauthname(NULL);
            continue;
        }
    }
 
    /*
     * Special handling for sslrootcert=system with no sslmode explicitly
     * defined. In this case we want to strengthen the default sslmode to
     * verify-full.
     */
    if (sslmode_default && sslrootcert)
    {
        if (sslrootcert->val && strcmp(sslrootcert->val, "system") == 0)
        {
            free(sslmode_default->val);
 
            sslmode_default->val = strdup("verify-full");
            if (!sslmode_default->val)
            {
                if (errorMessage)
                    libpq_append_error(errorMessage, "out of memory");
                return false;
            }
        }
    }
 
    return true;
}

References free, libpq_append_error(), parseServiceInfo(), pg_fe_getauthname(), option::val, and _PQconninfoOption::val.

Referenced by conninfo_array_parse(), conninfo_parse(), conninfo_uri_parse(), and PQconndefaults().

conninfo_array_parse()

static PQconninfoOption * conninfo_array_parse ( const char *const *  keywords, const char *const *  values, PQExpBuffer  errorMessage, bool  use_defaults, int  expand_dbname  )

static

Definition at line 6090 of file fe-connect.c.

{
    PQconninfoOption *options;
    PQconninfoOption *dbname_options = NULL;
    PQconninfoOption *option;
    int         i = 0;
 
    /*
     * If expand_dbname is non-zero, check keyword "dbname" to see if val is
     * actually a recognized connection string.
     */
    while (expand_dbname && keywords[i])
    {
        const char *pname = keywords[i];
        const char *pvalue = values[i];
 
        /* first find "dbname" if any */
        if (strcmp(pname, "dbname") == 0 && pvalue)
        {
            /*
             * If value is a connection string, parse it, but do not use
             * defaults here -- those get picked up later. We only want to
             * override for those parameters actually passed.
             */
            if (recognized_connection_string(pvalue))
            {
                dbname_options = parse_connection_string(pvalue, errorMessage, false);
                if (dbname_options == NULL)
                    return NULL;
            }
            break;
        }
        ++i;
    }
 
    /* Make a working copy of PQconninfoOptions */
    options = conninfo_init(errorMessage);
    if (options == NULL)
    {
        PQconninfoFree(dbname_options);
        return NULL;
    }
 
    /* Parse the keywords/values arrays */
    i = 0;
    while (keywords[i])
    {
        const char *pname = keywords[i];
        const char *pvalue = values[i];
 
        if (pvalue != NULL && pvalue[0] != '\0')
        {
            /* Search for the param record */
            for (option = options; option->keyword != NULL; option++)
            {
                if (strcmp(option->keyword, pname) == 0)
                    break;
            }
 
            /* Check for invalid connection option */
            if (option->keyword == NULL)
            {
                libpq_append_error(errorMessage, "invalid connection option \"%s\"", pname);
                PQconninfoFree(options);
                PQconninfoFree(dbname_options);
                return NULL;
            }
 
            /*
             * If we are on the first dbname parameter, and we have a parsed
             * connection string, copy those parameters across, overriding any
             * existing previous settings.
             */
            if (strcmp(pname, "dbname") == 0 && dbname_options)
            {
                PQconninfoOption *str_option;
 
                for (str_option = dbname_options; str_option->keyword != NULL; str_option++)
                {
                    if (str_option->val != NULL)
                    {
                        int         k;
 
                        for (k = 0; options[k].keyword; k++)
                        {
                            if (strcmp(options[k].keyword, str_option->keyword) == 0)
                            {
                                free(options[k].val);
                                options[k].val = strdup(str_option->val);
                                if (!options[k].val)
                                {
                                    libpq_append_error(errorMessage, "out of memory");
                                    PQconninfoFree(options);
                                    PQconninfoFree(dbname_options);
                                    return NULL;
                                }
                                break;
                            }
                        }
                    }
                }
 
                /*
                 * Forget the parsed connection string, so that any subsequent
                 * dbname parameters will not be expanded.
                 */
                PQconninfoFree(dbname_options);
                dbname_options = NULL;
            }
            else
            {
                /*
                 * Store the value, overriding previous settings
                 */
                free(option->val);
                option->val = strdup(pvalue);
                if (!option->val)
                {
                    libpq_append_error(errorMessage, "out of memory");
                    PQconninfoFree(options);
                    PQconninfoFree(dbname_options);
                    return NULL;
                }
            }
        }
        ++i;
    }
    PQconninfoFree(dbname_options);
 
    /*
     * Add in defaults if the caller wants that.
     */
    if (use_defaults)
    {
        if (!conninfo_add_defaults(options, errorMessage))
        {
            PQconninfoFree(options);
            return NULL;
        }
    }
 
    return options;
}

References conninfo_add_defaults(), conninfo_init(), free, i, _PQconninfoOption::keyword, keywords, libpq_append_error(), options, parse_connection_string(), PQconninfoFree(), recognized_connection_string(), option::val, val, _PQconninfoOption::val, and values.

Referenced by PQconnectStartParams().

conninfo_find()

static PQconninfoOption * conninfo_find ( PQconninfoOption *  connOptions, const char *  keyword  )

static

Definition at line 7021 of file fe-connect.c.

{
    PQconninfoOption *option;
 
    for (option = connOptions; option->keyword != NULL; option++)
    {
        if (strcmp(option->keyword, keyword) == 0)
            return option;
    }
 
    return NULL;
}

Referenced by conninfo_getval(), and conninfo_storeval().

conninfo_getval()

static const char * conninfo_getval ( PQconninfoOption *  connOptions, const char *  keyword  )

static

Definition at line 6931 of file fe-connect.c.

{
    PQconninfoOption *option;
 
    option = conninfo_find(connOptions, keyword);
 
    return option ? option->val : NULL;
}

References conninfo_find(), and option::val.

Referenced by fillPGconn(), and parseServiceInfo().

conninfo_init()

static PQconninfoOption * conninfo_init ( PQExpBuffer  errorMessage )

static

Definition at line 5821 of file fe-connect.c.

{
    PQconninfoOption *options;
    PQconninfoOption *opt_dest;
    const internalPQconninfoOption *cur_opt;
 
    /*
     * Get enough memory for all options in PQconninfoOptions, even if some
     * end up being filtered out.
     */
    options = (PQconninfoOption *) malloc(sizeof(PQconninfoOption) * sizeof(PQconninfoOptions) / sizeof(PQconninfoOptions[0]));
    if (options == NULL)
    {
        libpq_append_error(errorMessage, "out of memory");
        return NULL;
    }
    opt_dest = options;
 
    for (cur_opt = PQconninfoOptions; cur_opt->keyword; cur_opt++)
    {
        /* Only copy the public part of the struct, not the full internal */
        memcpy(opt_dest, cur_opt, sizeof(PQconninfoOption));
        opt_dest++;
    }
    MemSet(opt_dest, 0, sizeof(PQconninfoOption));
 
    return options;
}

References _internalPQconninfoOption::keyword, libpq_append_error(), malloc, MemSet, options, and PQconninfoOptions.

Referenced by conninfo_array_parse(), conninfo_parse(), conninfo_uri_parse(), PQconndefaults(), and PQconninfo().

conninfo_parse()

static PQconninfoOption * conninfo_parse ( const char *  conninfo, PQExpBuffer  errorMessage, bool  use_defaults  )

static

Definition at line 5914 of file fe-connect.c.

{
    char       *pname;
    char       *pval;
    char       *buf;
    char       *cp;
    char       *cp2;
    PQconninfoOption *options;
 
    /* Make a working copy of PQconninfoOptions */
    options = conninfo_init(errorMessage);
    if (options == NULL)
        return NULL;
 
    /* Need a modifiable copy of the input string */
    if ((buf = strdup(conninfo)) == NULL)
    {
        libpq_append_error(errorMessage, "out of memory");
        PQconninfoFree(options);
        return NULL;
    }
    cp = buf;
 
    while (*cp)
    {
        /* Skip blanks before the parameter name */
        if (isspace((unsigned char) *cp))
        {
            cp++;
            continue;
        }
 
        /* Get the parameter name */
        pname = cp;
        while (*cp)
        {
            if (*cp == '=')
                break;
            if (isspace((unsigned char) *cp))
            {
                *cp++ = '\0';
                while (*cp)
                {
                    if (!isspace((unsigned char) *cp))
                        break;
                    cp++;
                }
                break;
            }
            cp++;
        }
 
        /* Check that there is a following '=' */
        if (*cp != '=')
        {
            libpq_append_error(errorMessage,
                               "missing \"=\" after \"%s\" in connection info string",
                               pname);
            PQconninfoFree(options);
            free(buf);
            return NULL;
        }
        *cp++ = '\0';
 
        /* Skip blanks after the '=' */
        while (*cp)
        {
            if (!isspace((unsigned char) *cp))
                break;
            cp++;
        }
 
        /* Get the parameter value */
        pval = cp;
 
        if (*cp != '\'')
        {
            cp2 = pval;
            while (*cp)
            {
                if (isspace((unsigned char) *cp))
                {
                    *cp++ = '\0';
                    break;
                }
                if (*cp == '\\')
                {
                    cp++;
                    if (*cp != '\0')
                        *cp2++ = *cp++;
                }
                else
                    *cp2++ = *cp++;
            }
            *cp2 = '\0';
        }
        else
        {
            cp2 = pval;
            cp++;
            for (;;)
            {
                if (*cp == '\0')
                {
                    libpq_append_error(errorMessage, "unterminated quoted string in connection info string");
                    PQconninfoFree(options);
                    free(buf);
                    return NULL;
                }
                if (*cp == '\\')
                {
                    cp++;
                    if (*cp != '\0')
                        *cp2++ = *cp++;
                    continue;
                }
                if (*cp == '\'')
                {
                    *cp2 = '\0';
                    cp++;
                    break;
                }
                *cp2++ = *cp++;
            }
        }
 
        /*
         * Now that we have the name and the value, store the record.
         */
        if (!conninfo_storeval(options, pname, pval, errorMessage, false, false))
        {
            PQconninfoFree(options);
            free(buf);
            return NULL;
        }
    }
 
    /* Done with the modifiable input string */
    free(buf);
 
    /*
     * Add in defaults if the caller wants that.
     */
    if (use_defaults)
    {
        if (!conninfo_add_defaults(options, errorMessage))
        {
            PQconninfoFree(options);
            return NULL;
        }
    }
 
    return options;
}

References buf, conninfo_add_defaults(), conninfo_init(), conninfo_storeval(), free, libpq_append_error(), options, and PQconninfoFree().

Referenced by parse_connection_string().

conninfo_storeval()

static PQconninfoOption * conninfo_storeval ( PQconninfoOption *  connOptions, const char *  keyword, const char *  value, PQExpBuffer  errorMessage, bool  ignoreMissing, bool  uri_decode  )

static

Definition at line 6957 of file fe-connect.c.

{
    PQconninfoOption *option;
    char       *value_copy;
 
    /*
     * For backwards compatibility, requiressl=1 gets translated to
     * sslmode=require, and requiressl=0 gets translated to sslmode=prefer
     * (which is the default for sslmode).
     */
    if (strcmp(keyword, "requiressl") == 0)
    {
        keyword = "sslmode";
        if (value[0] == '1')
            value = "require";
        else
            value = "prefer";
    }
 
    option = conninfo_find(connOptions, keyword);
    if (option == NULL)
    {
        if (!ignoreMissing)
            libpq_append_error(errorMessage,
                               "invalid connection option \"%s\"",
                               keyword);
        return NULL;
    }
 
    if (uri_decode)
    {
        value_copy = conninfo_uri_decode(value, errorMessage);
        if (value_copy == NULL)
            /* conninfo_uri_decode already set an error message */
            return NULL;
    }
    else
    {
        value_copy = strdup(value);
        if (value_copy == NULL)
        {
            libpq_append_error(errorMessage, "out of memory");
            return NULL;
        }
    }
 
    free(option->val);
    option->val = value_copy;
 
    return option;
}

References conninfo_find(), conninfo_uri_decode(), free, libpq_append_error(), option::val, and value.

Referenced by conninfo_parse(), conninfo_uri_parse_options(), conninfo_uri_parse_params(), and PQconninfo().

conninfo_uri_decode()

static char * conninfo_uri_decode ( const char *  str, PQExpBuffer  errorMessage  )

static

Definition at line 6810 of file fe-connect.c.

{
    char       *buf;            /* result */
    char       *p;              /* output location */
    const char *q = str;        /* input location */
 
    buf = malloc(strlen(str) + 1);
    if (buf == NULL)
    {
        libpq_append_error(errorMessage, "out of memory");
        return NULL;
    }
    p = buf;
 
    /* skip leading whitespaces */
    for (const char *s = q; *s == ' '; s++)
    {
        q++;
        continue;
    }
 
    for (;;)
    {
        if (*q != '%')
        {
            /* if found a whitespace or NUL, the string ends */
            if (*q == ' ' || *q == '\0')
                goto end;
 
            /* copy character */
            *(p++) = *(q++);
        }
        else
        {
            int         hi;
            int         lo;
            int         c;
 
            ++q;                /* skip the percent sign itself */
 
            /*
             * Possible EOL will be caught by the first call to
             * get_hexdigit(), so we never dereference an invalid q pointer.
             */
            if (!(get_hexdigit(*q++, &hi) && get_hexdigit(*q++, &lo)))
            {
                libpq_append_error(errorMessage,
                                   "invalid percent-encoded token: \"%s\"",
                                   str);
                free(buf);
                return NULL;
            }
 
            c = (hi << 4) | lo;
            if (c == 0)
            {
                libpq_append_error(errorMessage,
                                   "forbidden value %%00 in percent-encoded value: \"%s\"",
                                   str);
                free(buf);
                return NULL;
            }
            *(p++) = c;
        }
    }
 
end:
 
    /* skip trailing whitespaces */
    for (const char *s = q; *s == ' '; s++)
    {
        q++;
        continue;
    }
 
    /* Not at the end of the string yet?  Fail. */
    if (*q != '\0')
    {
        libpq_append_error(errorMessage,
                           "unexpected spaces found in \"%s\", use percent-encoded spaces (%%20) instead",
                           str);
        free(buf);
        return NULL;
    }
 
    /* Copy NUL terminator */
    *p = '\0';
 
    return buf;
}

References buf, free, get_hexdigit(), libpq_append_error(), malloc, and str.

Referenced by conninfo_storeval(), and conninfo_uri_parse_params().

conninfo_uri_parse()

static PQconninfoOption * conninfo_uri_parse ( const char *  uri, PQExpBuffer  errorMessage, bool  use_defaults  )

static

Definition at line 6383 of file fe-connect.c.

{
    PQconninfoOption *options;
 
    /* Make a working copy of PQconninfoOptions */
    options = conninfo_init(errorMessage);
    if (options == NULL)
        return NULL;
 
    if (!conninfo_uri_parse_options(options, uri, errorMessage))
    {
        PQconninfoFree(options);
        return NULL;
    }
 
    /*
     * Add in defaults if the caller wants that.
     */
    if (use_defaults)
    {
        if (!conninfo_add_defaults(options, errorMessage))
        {
            PQconninfoFree(options);
            return NULL;
        }
    }
 
    return options;
}

References conninfo_add_defaults(), conninfo_init(), conninfo_uri_parse_options(), options, and PQconninfoFree().

Referenced by parse_connection_string().

conninfo_uri_parse_options()

static bool conninfo_uri_parse_options ( PQconninfoOption *  options, const char *  uri, PQExpBuffer  errorMessage  )

static

Definition at line 6436 of file fe-connect.c.

{
    int         prefix_len;
    char       *p;
    char       *buf = NULL;
    char       *start;
    char        prevchar = '\0';
    char       *user = NULL;
    char       *host = NULL;
    bool        retval = false;
    PQExpBufferData hostbuf;
    PQExpBufferData portbuf;
 
    initPQExpBuffer(&hostbuf);
    initPQExpBuffer(&portbuf);
    if (PQExpBufferDataBroken(hostbuf) || PQExpBufferDataBroken(portbuf))
    {
        libpq_append_error(errorMessage, "out of memory");
        goto cleanup;
    }
 
    /* need a modifiable copy of the input URI */
    buf = strdup(uri);
    if (buf == NULL)
    {
        libpq_append_error(errorMessage, "out of memory");
        goto cleanup;
    }
    start = buf;
 
    /* Skip the URI prefix */
    prefix_len = uri_prefix_length(uri);
    if (prefix_len == 0)
    {
        /* Should never happen */
        libpq_append_error(errorMessage,
                           "invalid URI propagated to internal parser routine: \"%s\"",
                           uri);
        goto cleanup;
    }
    start += prefix_len;
    p = start;
 
    /* Look ahead for possible user credentials designator */
    while (*p && *p != '@' && *p != '/')
        ++p;
    if (*p == '@')
    {
        /*
         * Found username/password designator, so URI should be of the form
         * "scheme://user[:password]@[netloc]".
         */
        user = start;
 
        p = user;
        while (*p != ':' && *p != '@')
            ++p;
 
        /* Save last char and cut off at end of user name */
        prevchar = *p;
        *p = '\0';
 
        if (*user &&
            !conninfo_storeval(options, "user", user,
                               errorMessage, false, true))
            goto cleanup;
 
        if (prevchar == ':')
        {
            const char *password = p + 1;
 
            while (*p != '@')
                ++p;
            *p = '\0';
 
            if (*password &&
                !conninfo_storeval(options, "password", password,
                                   errorMessage, false, true))
                goto cleanup;
        }
 
        /* Advance past end of parsed user name or password token */
        ++p;
    }
    else
    {
        /*
         * No username/password designator found.  Reset to start of URI.
         */
        p = start;
    }
 
    /*
     * There may be multiple netloc[:port] pairs, each separated from the next
     * by a comma.  When we initially enter this loop, "p" has been
     * incremented past optional URI credential information at this point and
     * now points at the "netloc" part of the URI.  On subsequent loop
     * iterations, "p" has been incremented past the comma separator and now
     * points at the start of the next "netloc".
     */
    for (;;)
    {
        /*
         * Look for IPv6 address.
         */
        if (*p == '[')
        {
            host = ++p;
            while (*p && *p != ']')
                ++p;
            if (!*p)
            {
                libpq_append_error(errorMessage,
                                   "end of string reached when looking for matching \"]\" in IPv6 host address in URI: \"%s\"",
                                   uri);
                goto cleanup;
            }
            if (p == host)
            {
                libpq_append_error(errorMessage,
                                   "IPv6 host address may not be empty in URI: \"%s\"",
                                   uri);
                goto cleanup;
            }
 
            /* Cut off the bracket and advance */
            *(p++) = '\0';
 
            /*
             * The address may be followed by a port specifier or a slash or a
             * query or a separator comma.
             */
            if (*p && *p != ':' && *p != '/' && *p != '?' && *p != ',')
            {
                libpq_append_error(errorMessage,
                                   "unexpected character \"%c\" at position %d in URI (expected \":\" or \"/\"): \"%s\"",
                                   *p, (int) (p - buf + 1), uri);
                goto cleanup;
            }
        }
        else
        {
            /* not an IPv6 address: DNS-named or IPv4 netloc */
            host = p;
 
            /*
             * Look for port specifier (colon) or end of host specifier
             * (slash) or query (question mark) or host separator (comma).
             */
            while (*p && *p != ':' && *p != '/' && *p != '?' && *p != ',')
                ++p;
        }
 
        /* Save the hostname terminator before we null it */
        prevchar = *p;
        *p = '\0';
 
        appendPQExpBufferStr(&hostbuf, host);
 
        if (prevchar == ':')
        {
            const char *port = ++p; /* advance past host terminator */
 
            while (*p && *p != '/' && *p != '?' && *p != ',')
                ++p;
 
            prevchar = *p;
            *p = '\0';
 
            appendPQExpBufferStr(&portbuf, port);
        }
 
        if (prevchar != ',')
            break;
        ++p;                    /* advance past comma separator */
        appendPQExpBufferChar(&hostbuf, ',');
        appendPQExpBufferChar(&portbuf, ',');
    }
 
    /* Save final values for host and port. */
    if (PQExpBufferDataBroken(hostbuf) || PQExpBufferDataBroken(portbuf))
        goto cleanup;
    if (hostbuf.data[0] &&
        !conninfo_storeval(options, "host", hostbuf.data,
                           errorMessage, false, true))
        goto cleanup;
    if (portbuf.data[0] &&
        !conninfo_storeval(options, "port", portbuf.data,
                           errorMessage, false, true))
        goto cleanup;
 
    if (prevchar && prevchar != '?')
    {
        const char *dbname = ++p;   /* advance past host terminator */
 
        /* Look for query parameters */
        while (*p && *p != '?')
            ++p;
 
        prevchar = *p;
        *p = '\0';
 
        /*
         * Avoid setting dbname to an empty string, as it forces the default
         * value (username) and ignores $PGDATABASE, as opposed to not setting
         * it at all.
         */
        if (*dbname &&
            !conninfo_storeval(options, "dbname", dbname,
                               errorMessage, false, true))
            goto cleanup;
    }
 
    if (prevchar)
    {
        ++p;                    /* advance past terminator */
 
        if (!conninfo_uri_parse_params(p, options, errorMessage))
            goto cleanup;
    }
 
    /* everything parsed okay */
    retval = true;
 
cleanup:
    termPQExpBuffer(&hostbuf);
    termPQExpBuffer(&portbuf);
    free(buf);
    return retval;
}

References appendPQExpBufferChar(), appendPQExpBufferStr(), buf, cleanup(), conninfo_storeval(), conninfo_uri_parse_params(), PQExpBufferData::data, dbname, free, initPQExpBuffer(), libpq_append_error(), password, port, PQExpBufferDataBroken, start, termPQExpBuffer(), uri_prefix_length(), and user.

Referenced by conninfo_uri_parse().

conninfo_uri_parse_params()

static bool conninfo_uri_parse_params ( char *  params, PQconninfoOption *  connOptions, PQExpBuffer  errorMessage  )

static

Definition at line 6677 of file fe-connect.c.

{
    while (*params)
    {
        char       *keyword = params;
        char       *value = NULL;
        char       *p = params;
        bool        malloced = false;
        int         oldmsglen;
 
        /*
         * Scan the params string for '=' and '&', marking the end of keyword
         * and value respectively.
         */
        for (;;)
        {
            if (*p == '=')
            {
                /* Was there '=' already? */
                if (value != NULL)
                {
                    libpq_append_error(errorMessage,
                                       "extra key/value separator \"=\" in URI query parameter: \"%s\"",
                                       keyword);
                    return false;
                }
                /* Cut off keyword, advance to value */
                *p++ = '\0';
                value = p;
            }
            else if (*p == '&' || *p == '\0')
            {
                /*
                 * If not at the end, cut off value and advance; leave p
                 * pointing to start of the next parameter, if any.
                 */
                if (*p != '\0')
                    *p++ = '\0';
                /* Was there '=' at all? */
                if (value == NULL)
                {
                    libpq_append_error(errorMessage,
                                       "missing key/value separator \"=\" in URI query parameter: \"%s\"",
                                       keyword);
                    return false;
                }
                /* Got keyword and value, go process them. */
                break;
            }
            else
                ++p;            /* Advance over all other bytes. */
        }
 
        keyword = conninfo_uri_decode(keyword, errorMessage);
        if (keyword == NULL)
        {
            /* conninfo_uri_decode already set an error message */
            return false;
        }
        value = conninfo_uri_decode(value, errorMessage);
        if (value == NULL)
        {
            /* conninfo_uri_decode already set an error message */
            free(keyword);
            return false;
        }
        malloced = true;
 
        /*
         * Special keyword handling for improved JDBC compatibility.
         */
        if (strcmp(keyword, "ssl") == 0 &&
            strcmp(value, "true") == 0)
        {
            free(keyword);
            free(value);
            malloced = false;
 
            keyword = "sslmode";
            value = "require";
        }
 
        /*
         * Store the value if the corresponding option exists; ignore
         * otherwise.  At this point both keyword and value are not
         * URI-encoded.
         */
        oldmsglen = errorMessage->len;
        if (!conninfo_storeval(connOptions, keyword, value,
                               errorMessage, true, false))
        {
            /* Insert generic message if conninfo_storeval didn't give one. */
            if (errorMessage->len == oldmsglen)
                libpq_append_error(errorMessage,
                                   "invalid URI query parameter: \"%s\"",
                                   keyword);
            /* And fail. */
            if (malloced)
            {
                free(keyword);
                free(value);
            }
            return false;
        }
 
        if (malloced)
        {
            free(keyword);
            free(value);
        }
 
        /* Proceed to next key=value pair, if any */
        params = p;
    }
 
    return true;
}

References conninfo_storeval(), conninfo_uri_decode(), free, PQExpBufferData::len, libpq_append_error(), and value.

Referenced by conninfo_uri_parse_options().

count_comma_separated_elems()

static int count_comma_separated_elems ( const char *  input )

static

Definition at line 1043 of file fe-connect.c.

{
    int         n;
 
    n = 1;
    for (; *input != '\0'; input++)
    {
        if (*input == ',')
            n++;
    }
 
    return n;
}

References input.

Referenced by pqConnectOptions2().

default_threadlock()

static void default_threadlock ( int  acquire )

static

Definition at line 7875 of file fe-connect.c.

{
    static pthread_mutex_t singlethread_lock = PTHREAD_MUTEX_INITIALIZER;
 
    if (acquire)
    {
        if (pthread_mutex_lock(&singlethread_lock))
            Assert(false);
    }
    else
    {
        if (pthread_mutex_unlock(&singlethread_lock))
            Assert(false);
    }
}

References Assert, PTHREAD_MUTEX_INITIALIZER, pthread_mutex_lock(), and pthread_mutex_unlock().

Referenced by PQregisterThreadLock().

defaultNoticeProcessor()

static void defaultNoticeProcessor ( void *  arg, const char *  message  )

static

Definition at line 7485 of file fe-connect.c.

{
    (void) arg;                 /* not used */
    /* Note: we expect the supplied string to end with a newline already. */
    fprintf(stderr, "%s", message);
}

References arg, and fprintf.

Referenced by pqMakeEmptyPGconn().

defaultNoticeReceiver()

static void defaultNoticeReceiver ( void *  arg, const PGresult *  res  )

static

Definition at line 7470 of file fe-connect.c.

{
    (void) arg;                 /* not used */
    if (res->noticeHooks.noticeProc != NULL)
        res->noticeHooks.noticeProc(res->noticeHooks.noticeProcArg,
                                    PQresultErrorMessage(res));
}

References arg, pg_result::noticeHooks, PGNoticeHooks::noticeProc, PGNoticeHooks::noticeProcArg, PQresultErrorMessage(), and res.

Referenced by pqMakeEmptyPGconn().

emitHostIdentityInfo()

static void emitHostIdentityInfo ( PGconn *  conn, const char *  host_addr  )

static

Definition at line 2152 of file fe-connect.c.

{
    if (conn->raddr.addr.ss_family == AF_UNIX)
    {
        char        service[NI_MAXHOST];
 
        pg_getnameinfo_all(&conn->raddr.addr, conn->raddr.salen,
                           NULL, 0,
                           service, sizeof(service),
                           NI_NUMERICSERV);
        appendPQExpBuffer(&conn->errorMessage,
                          libpq_gettext("connection to server on socket \"%s\" failed: "),
                          service);
    }
    else
    {
        const char *displayed_host;
        const char *displayed_port;
 
        /* To which host and port were we actually connecting? */
        if (conn->connhost[conn->whichhost].type == CHT_HOST_ADDRESS)
            displayed_host = conn->connhost[conn->whichhost].hostaddr;
        else
            displayed_host = conn->connhost[conn->whichhost].host;
        displayed_port = conn->connhost[conn->whichhost].port;
        if (displayed_port == NULL || displayed_port[0] == '\0')
            displayed_port = DEF_PGPORT_STR;
 
        /*
         * If the user did not supply an IP address using 'hostaddr', and
         * 'host' was missing or does not match our lookup, display the
         * looked-up IP address.
         */
        if (conn->connhost[conn->whichhost].type != CHT_HOST_ADDRESS &&
            host_addr[0] &&
            strcmp(displayed_host, host_addr) != 0)
            appendPQExpBuffer(&conn->errorMessage,
                              libpq_gettext("connection to server at \"%s\" (%s), port %s failed: "),
                              displayed_host, host_addr,
                              displayed_port);
        else
            appendPQExpBuffer(&conn->errorMessage,
                              libpq_gettext("connection to server at \"%s\", port %s failed: "),
                              displayed_host,
                              displayed_port);
    }
}

References SockAddr::addr, appendPQExpBuffer(), CHT_HOST_ADDRESS, conn, pg_conn::connhost, pg_conn::errorMessage, pg_conn_host::host, pg_conn_host::hostaddr, libpq_gettext, pg_getnameinfo_all(), pg_conn_host::port, pg_conn::raddr, SockAddr::salen, pg_conn_host::type, and pg_conn::whichhost.

Referenced by PQconnectPoll().

fillPGconn()

static bool fillPGconn ( PGconn *  conn, PQconninfoOption *  connOptions  )

static

Definition at line 927 of file fe-connect.c.

{
    const internalPQconninfoOption *option;
 
    for (option = PQconninfoOptions; option->keyword; option++)
    {
        if (option->connofs >= 0)
        {
            const char *tmp = conninfo_getval(connOptions, option->keyword);
 
            if (tmp)
            {
                char      **connmember = (char **) ((char *) conn + option->connofs);
 
                free(*connmember);
                *connmember = strdup(tmp);
                if (*connmember == NULL)
                {
                    libpq_append_conn_error(conn, "out of memory");
                    return false;
                }
            }
        }
    }
 
    return true;
}

References conn, conninfo_getval(), free, libpq_append_conn_error(), and PQconninfoOptions.

Referenced by connectOptions1(), and PQconnectStartParams().

freePGconn()

static void freePGconn ( PGconn *  conn )

static

Definition at line 4693 of file fe-connect.c.

{
    /* let any event procs clean up their state data */
    for (int i = 0; i < conn->nEvents; i++)
    {
        PGEventConnDestroy evt;
 
        evt.conn = conn;
        (void) conn->events[i].proc(PGEVT_CONNDESTROY, &evt,
                                    conn->events[i].passThrough);
        free(conn->events[i].name);
    }
 
    release_conn_addrinfo(conn);
    pqReleaseConnHosts(conn);
 
    free(conn->client_encoding_initial);
    free(conn->events);
    free(conn->pghost);
    free(conn->pghostaddr);
    free(conn->pgport);
    free(conn->connect_timeout);
    free(conn->pgtcp_user_timeout);
    free(conn->pgoptions);
    free(conn->appname);
    free(conn->fbappname);
    free(conn->dbName);
    free(conn->replication);
    free(conn->pguser);
    if (conn->pgpass)
    {
        explicit_bzero(conn->pgpass, strlen(conn->pgpass));
        free(conn->pgpass);
    }
    free(conn->pgpassfile);
    free(conn->channel_binding);
    free(conn->keepalives);
    free(conn->keepalives_idle);
    free(conn->keepalives_interval);
    free(conn->keepalives_count);
    free(conn->sslmode);
    free(conn->sslnegotiation);
    free(conn->sslcert);
    free(conn->sslkey);
    if (conn->sslpassword)
    {
        explicit_bzero(conn->sslpassword, strlen(conn->sslpassword));
        free(conn->sslpassword);
    }
    free(conn->sslcertmode);
    free(conn->sslrootcert);
    free(conn->sslcrl);
    free(conn->sslcrldir);
    free(conn->sslcompression);
    free(conn->sslsni);
    free(conn->requirepeer);
    free(conn->require_auth);
    free(conn->ssl_min_protocol_version);
    free(conn->ssl_max_protocol_version);
    free(conn->gssencmode);
    free(conn->krbsrvname);
    free(conn->gsslib);
    free(conn->gssdelegation);
    free(conn->connip);
    /* Note that conn->Pfdebug is not ours to close or free */
    free(conn->write_err_msg);
    free(conn->inBuffer);
    free(conn->outBuffer);
    free(conn->rowBuf);
    free(conn->target_session_attrs);
    free(conn->load_balance_hosts);
    free(conn->scram_client_key);
    free(conn->scram_server_key);
    termPQExpBuffer(&conn->errorMessage);
    termPQExpBuffer(&conn->workBuffer);
 
    free(conn);
}

References pg_conn::appname, pg_conn::channel_binding, pg_conn::client_encoding_initial, conn, PGEventConnDestroy::conn, pg_conn::connect_timeout, pg_conn::connip, pg_conn::dbName, pg_conn::errorMessage, pg_conn::events, explicit_bzero(), pg_conn::fbappname, free, pg_conn::gssdelegation, pg_conn::gssencmode, pg_conn::gsslib, i, pg_conn::inBuffer, pg_conn::keepalives, pg_conn::keepalives_count, pg_conn::keepalives_idle, pg_conn::keepalives_interval, pg_conn::krbsrvname, pg_conn::load_balance_hosts, PGEvent::name, pg_conn::nEvents, pg_conn::outBuffer, PGEvent::passThrough, PGEVT_CONNDESTROY, pg_conn::pghost, pg_conn::pghostaddr, pg_conn::pgoptions, pg_conn::pgpass, pg_conn::pgpassfile, pg_conn::pgport, pg_conn::pgtcp_user_timeout, pg_conn::pguser, pqReleaseConnHosts(), PGEvent::proc, release_conn_addrinfo(), pg_conn::replication, pg_conn::require_auth, pg_conn::requirepeer, pg_conn::rowBuf, pg_conn::scram_client_key, pg_conn::scram_server_key, pg_conn::ssl_max_protocol_version, pg_conn::ssl_min_protocol_version, pg_conn::sslcert, pg_conn::sslcertmode, pg_conn::sslcompression, pg_conn::sslcrl, pg_conn::sslcrldir, pg_conn::sslkey, pg_conn::sslmode, pg_conn::sslnegotiation, pg_conn::sslpassword, pg_conn::sslrootcert, pg_conn::sslsni, pg_conn::target_session_attrs, termPQExpBuffer(), pg_conn::workBuffer, and pg_conn::write_err_msg.

Referenced by PQfinish(), and pqMakeEmptyPGconn().

get_hexdigit()

static bool get_hexdigit ( char  digit, int *  value  )

static

Definition at line 6910 of file fe-connect.c.

{
    if ('0' <= digit && digit <= '9')
        *value = digit - '0';
    else if ('A' <= digit && digit <= 'F')
        *value = digit - 'A' + 10;
    else if ('a' <= digit && digit <= 'f')
        *value = digit - 'a' + 10;
    else
        return false;
 
    return true;
}

References value.

Referenced by conninfo_uri_decode().

getHostaddr()

static void getHostaddr ( PGconn *  conn, char *  host_addr, int  host_addr_len  )

static

Definition at line 2119 of file fe-connect.c.

{
    struct sockaddr_storage *addr = &conn->raddr.addr;
 
    if (addr->ss_family == AF_INET)
    {
        if (pg_inet_net_ntop(AF_INET,
                             &((struct sockaddr_in *) addr)->sin_addr.s_addr,
                             32,
                             host_addr, host_addr_len) == NULL)
            host_addr[0] = '\0';
    }
    else if (addr->ss_family == AF_INET6)
    {
        if (pg_inet_net_ntop(AF_INET6,
                             &((struct sockaddr_in6 *) addr)->sin6_addr.s6_addr,
                             128,
                             host_addr, host_addr_len) == NULL)
            host_addr[0] = '\0';
    }
    else
        host_addr[0] = '\0';
}

References SockAddr::addr, conn, pg_inet_net_ntop(), and pg_conn::raddr.

Referenced by PQconnectPoll().

init_allowed_encryption_methods()

static bool init_allowed_encryption_methods ( PGconn *  conn )

static

Definition at line 4350 of file fe-connect.c.

{
    if (conn->raddr.addr.ss_family == AF_UNIX)
    {
        /* Don't request SSL or GSSAPI over Unix sockets */
        conn->allowed_enc_methods &= ~(ENC_SSL | ENC_GSSAPI);
 
        /*
         * XXX: we probably should not do this. sslmode=require works
         * differently
         */
        if (conn->gssencmode[0] == 'r')
        {
            libpq_append_conn_error(conn,
                                    "GSSAPI encryption required but it is not supported over a local socket");
            conn->allowed_enc_methods = 0;
            conn->current_enc_method = ENC_ERROR;
            return false;
        }
 
        conn->allowed_enc_methods = ENC_PLAINTEXT;
        conn->current_enc_method = ENC_PLAINTEXT;
        return true;
    }
 
    /* initialize based on sslmode and gssencmode */
    conn->allowed_enc_methods = 0;
 
#ifdef USE_SSL
    /* sslmode anything but 'disable', and GSSAPI not required */
    if (conn->sslmode[0] != 'd' && conn->gssencmode[0] != 'r')
    {
        conn->allowed_enc_methods |= ENC_SSL;
    }
#endif
 
#ifdef ENABLE_GSS
    if (conn->gssencmode[0] != 'd')
        conn->allowed_enc_methods |= ENC_GSSAPI;
#endif
 
    if ((conn->sslmode[0] == 'd' || conn->sslmode[0] == 'p' || conn->sslmode[0] == 'a') &&
        (conn->gssencmode[0] == 'd' || conn->gssencmode[0] == 'p'))
    {
        conn->allowed_enc_methods |= ENC_PLAINTEXT;
    }
 
    return select_next_encryption_method(conn, false);
}

References SockAddr::addr, pg_conn::allowed_enc_methods, conn, pg_conn::current_enc_method, ENC_ERROR, ENC_GSSAPI, ENC_PLAINTEXT, ENC_SSL, pg_conn::gssencmode, libpq_append_conn_error(), pg_conn::raddr, select_next_encryption_method(), and pg_conn::sslmode.

Referenced by PQconnectPoll().

internal_ping()

static PGPing internal_ping ( PGconn *  conn )

static

Definition at line 4530 of file fe-connect.c.

{
    /* Say "no attempt" if we never got to PQconnectPoll */
    if (!conn || !conn->options_valid)
        return PQPING_NO_ATTEMPT;
 
    /* Attempt to complete the connection */
    if (conn->status != CONNECTION_BAD)
        (void) pqConnectDBComplete(conn);
 
    /* Definitely OK if we succeeded */
    if (conn->status != CONNECTION_BAD)
        return PQPING_OK;
 
    /*
     * Here begins the interesting part of "ping": determine the cause of the
     * failure in sufficient detail to decide what to return.  We do not want
     * to report that the server is not up just because we didn't have a valid
     * password, for example.  In fact, any sort of authentication request
     * implies the server is up.  (We need this check since the libpq side of
     * things might have pulled the plug on the connection before getting an
     * error as such from the postmaster.)
     */
    if (conn->auth_req_received)
        return PQPING_OK;
 
    /*
     * If we failed to get any ERROR response from the postmaster, report
     * PQPING_NO_RESPONSE.  This result could be somewhat misleading for a
     * pre-7.4 server, since it won't send back a SQLSTATE, but those are long
     * out of support.  Another corner case where the server could return a
     * failure without a SQLSTATE is fork failure, but PQPING_NO_RESPONSE
     * isn't totally unreasonable for that anyway.  We expect that every other
     * failure case in a modern server will produce a report with a SQLSTATE.
     *
     * NOTE: whenever we get around to making libpq generate SQLSTATEs for
     * client-side errors, we should either not store those into
     * last_sqlstate, or add an extra flag so we can tell client-side errors
     * apart from server-side ones.
     */
    if (strlen(conn->last_sqlstate) != 5)
        return PQPING_NO_RESPONSE;
 
    /*
     * Report PQPING_REJECT if server says it's not accepting connections.
     */
    if (strcmp(conn->last_sqlstate, ERRCODE_CANNOT_CONNECT_NOW) == 0)
        return PQPING_REJECT;
 
    /*
     * Any other SQLSTATE can be taken to indicate that the server is up.
     * Presumably it didn't like our username, password, or database name; or
     * perhaps it had some transient failure, but that should not be taken as
     * meaning "it's down".
     */
    return PQPING_OK;
}

References pg_conn::auth_req_received, conn, CONNECTION_BAD, ERRCODE_CANNOT_CONNECT_NOW, pg_conn::last_sqlstate, pg_conn::options_valid, pqConnectDBComplete(), PQPING_NO_ATTEMPT, PQPING_NO_RESPONSE, PQPING_OK, PQPING_REJECT, and pg_conn::status.

Referenced by PQping(), and PQpingParams().

libpq_prng_init()

static void libpq_prng_init ( PGconn *  conn )

static

Definition at line 1102 of file fe-connect.c.

{
    uint64      rseed;
    struct timeval tval = {0};
 
    if (pg_prng_strong_seed(&conn->prng_state))
        return;
 
    gettimeofday(&tval, NULL);
 
    rseed = ((uintptr_t) conn) ^
        ((uint64) getpid()) ^
        ((uint64) tval.tv_usec) ^
        ((uint64) tval.tv_sec);
 
    pg_prng_seed(&conn->prng_state, rseed);
}

References conn, gettimeofday(), pg_prng_seed(), pg_prng_strong_seed, and pg_conn::prng_state.

Referenced by pqConnectOptions2().

parse_comma_separated_list()

static char * parse_comma_separated_list ( char **  startptr, bool *  more  )

static

Definition at line 1067 of file fe-connect.c.

{
    char       *p;
    char       *s = *startptr;
    char       *e;
    int         len;
 
    /*
     * Search for the end of the current element; a comma or end-of-string
     * acts as a terminator.
     */
    e = s;
    while (*e != '\0' && *e != ',')
        ++e;
    *more = (*e == ',');
 
    len = e - s;
    p = (char *) malloc(sizeof(char) * (len + 1));
    if (p)
    {
        memcpy(p, s, len);
        p[len] = '\0';
    }
    *startptr = e + 1;
 
    return p;
}

References len, and malloc.

Referenced by pqConnectOptions2().

parse_connection_string()

static PQconninfoOption * parse_connection_string ( const char *  connstr, PQExpBuffer  errorMessage, bool  use_defaults  )

static

Definition at line 5860 of file fe-connect.c.

{
    /* Parse as URI if connection string matches URI prefix */
    if (uri_prefix_length(connstr) != 0)
        return conninfo_uri_parse(connstr, errorMessage, use_defaults);
 
    /* Parse as default otherwise */
    return conninfo_parse(connstr, errorMessage, use_defaults);
}

References conninfo_parse(), conninfo_uri_parse(), connstr, and uri_prefix_length().

Referenced by connectOptions1(), conninfo_array_parse(), and PQconninfoParse().

parseServiceFile()

static int parseServiceFile ( const char *  serviceFile, const char *  service, PQconninfoOption *  options, PQExpBuffer  errorMessage, bool *  group_found  )

static

Definition at line 5621 of file fe-connect.c.

{
    int         result = 0,
                linenr = 0,
                i;
    FILE       *f;
    char       *line;
    char        buf[1024];
 
    *group_found = false;
 
    f = fopen(serviceFile, "r");
    if (f == NULL)
    {
        libpq_append_error(errorMessage, "service file \"%s\" not found", serviceFile);
        return 1;
    }
 
    while ((line = fgets(buf, sizeof(buf), f)) != NULL)
    {
        int         len;
 
        linenr++;
 
        if (strlen(line) >= sizeof(buf) - 1)
        {
            libpq_append_error(errorMessage,
                               "line %d too long in service file \"%s\"",
                               linenr,
                               serviceFile);
            result = 2;
            goto exit;
        }
 
        /* ignore whitespace at end of line, especially the newline */
        len = strlen(line);
        while (len > 0 && isspace((unsigned char) line[len - 1]))
            line[--len] = '\0';
 
        /* ignore leading whitespace too */
        while (*line && isspace((unsigned char) line[0]))
            line++;
 
        /* ignore comments and empty lines */
        if (line[0] == '\0' || line[0] == '#')
            continue;
 
        /* Check for right groupname */
        if (line[0] == '[')
        {
            if (*group_found)
            {
                /* end of desired group reached; return success */
                goto exit;
            }
 
            if (strncmp(line + 1, service, strlen(service)) == 0 &&
                line[strlen(service) + 1] == ']')
                *group_found = true;
            else
                *group_found = false;
        }
        else
        {
            if (*group_found)
            {
                /*
                 * Finally, we are in the right group and can parse the line
                 */
                char       *key,
                           *val;
                bool        found_keyword;
 
#ifdef USE_LDAP
                if (strncmp(line, "ldap", 4) == 0)
                {
                    int         rc = ldapServiceLookup(line, options, errorMessage);
 
                    /* if rc = 2, go on reading for fallback */
                    switch (rc)
                    {
                        case 0:
                            goto exit;
                        case 1:
                        case 3:
                            result = 3;
                            goto exit;
                        case 2:
                            continue;
                    }
                }
#endif
 
                key = line;
                val = strchr(line, '=');
                if (val == NULL)
                {
                    libpq_append_error(errorMessage,
                                       "syntax error in service file \"%s\", line %d",
                                       serviceFile,
                                       linenr);
                    result = 3;
                    goto exit;
                }
                *val++ = '\0';
 
                if (strcmp(key, "service") == 0)
                {
                    libpq_append_error(errorMessage,
                                       "nested service specifications not supported in service file \"%s\", line %d",
                                       serviceFile,
                                       linenr);
                    result = 3;
                    goto exit;
                }
 
                /*
                 * Set the parameter --- but don't override any previous
                 * explicit setting.
                 */
                found_keyword = false;
                for (i = 0; options[i].keyword; i++)
                {
                    if (strcmp(options[i].keyword, key) == 0)
                    {
                        if (options[i].val == NULL)
                            options[i].val = strdup(val);
                        if (!options[i].val)
                        {
                            libpq_append_error(errorMessage, "out of memory");
                            result = 3;
                            goto exit;
                        }
                        found_keyword = true;
                        break;
                    }
                }
 
                if (!found_keyword)
                {
                    libpq_append_error(errorMessage,
                                       "syntax error in service file \"%s\", line %d",
                                       serviceFile,
                                       linenr);
                    result = 3;
                    goto exit;
                }
            }
        }
    }
 
exit:
    fclose(f);
 
    return result;
}

References buf, exit(), i, sort-test::key, len, libpq_append_error(), and val.

Referenced by parseServiceInfo().

parseServiceInfo()

static int parseServiceInfo ( PQconninfoOption *  options, PQExpBuffer  errorMessage  )

static

Definition at line 5553 of file fe-connect.c.

{
    const char *service = conninfo_getval(options, "service");
    char        serviceFile[MAXPGPATH];
    char       *env;
    bool        group_found = false;
    int         status;
    struct stat stat_buf;
 
    /*
     * We have to special-case the environment variable PGSERVICE here, since
     * this is and should be called before inserting environment defaults for
     * other connection options.
     */
    if (service == NULL)
        service = getenv("PGSERVICE");
 
    /* If no service name given, nothing to do */
    if (service == NULL)
        return 0;
 
    /*
     * Try PGSERVICEFILE if specified, else try ~/.pg_service.conf (if that
     * exists).
     */
    if ((env = getenv("PGSERVICEFILE")) != NULL)
        strlcpy(serviceFile, env, sizeof(serviceFile));
    else
    {
        char        homedir[MAXPGPATH];
 
        if (!pqGetHomeDirectory(homedir, sizeof(homedir)))
            goto next_file;
        snprintf(serviceFile, MAXPGPATH, "%s/%s", homedir, ".pg_service.conf");
        if (stat(serviceFile, &stat_buf) != 0)
            goto next_file;
    }
 
    status = parseServiceFile(serviceFile, service, options, errorMessage, &group_found);
    if (group_found || status != 0)
        return status;
 
next_file:
 
    /*
     * This could be used by any application so we can't use the binary
     * location to find our config files.
     */
    snprintf(serviceFile, MAXPGPATH, "%s/pg_service.conf",
             getenv("PGSYSCONFDIR") ? getenv("PGSYSCONFDIR") : SYSCONFDIR);
    if (stat(serviceFile, &stat_buf) != 0)
        goto last_file;
 
    status = parseServiceFile(serviceFile, service, options, errorMessage, &group_found);
    if (status != 0)
        return status;
 
last_file:
    if (!group_found)
    {
        libpq_append_error(errorMessage, "definition of service \"%s\" not found", service);
        return 3;
    }
 
    return 0;
}

References conninfo_getval(), libpq_append_error(), MAXPGPATH, parseServiceFile(), pqGetHomeDirectory(), snprintf, stat, and strlcpy().

Referenced by conninfo_add_defaults().

passwordFromFile()

static char * passwordFromFile ( const char *  hostname, const char *  port, const char *  dbname, const char *  username, const char *  pgpassfile  )

static

Definition at line 7534 of file fe-connect.c.

{
    FILE       *fp;
#ifndef WIN32
    struct stat stat_buf;
#endif
    PQExpBufferData buf;
 
    if (dbname == NULL || dbname[0] == '\0')
        return NULL;
 
    if (username == NULL || username[0] == '\0')
        return NULL;
 
    /* 'localhost' matches pghost of '' or the default socket directory */
    if (hostname == NULL || hostname[0] == '\0')
        hostname = DefaultHost;
    else if (is_unixsock_path(hostname))
 
        /*
         * We should probably use canonicalize_path(), but then we have to
         * bring path.c into libpq, and it doesn't seem worth it.
         */
        if (strcmp(hostname, DEFAULT_PGSOCKET_DIR) == 0)
            hostname = DefaultHost;
 
    if (port == NULL || port[0] == '\0')
        port = DEF_PGPORT_STR;
 
    /* If password file cannot be opened, ignore it. */
    fp = fopen(pgpassfile, "r");
    if (fp == NULL)
        return NULL;
 
#ifndef WIN32
    if (fstat(fileno(fp), &stat_buf) != 0)
    {
        fclose(fp);
        return NULL;
    }
 
    if (!S_ISREG(stat_buf.st_mode))
    {
        fprintf(stderr,
                libpq_gettext("WARNING: password file \"%s\" is not a plain file\n"),
                pgpassfile);
        fclose(fp);
        return NULL;
    }
 
    /* If password file is insecure, alert the user and ignore it. */
    if (stat_buf.st_mode & (S_IRWXG | S_IRWXO))
    {
        fprintf(stderr,
                libpq_gettext("WARNING: password file \"%s\" has group or world access; permissions should be u=rw (0600) or less\n"),
                pgpassfile);
        fclose(fp);
        return NULL;
    }
#else
 
    /*
     * On Win32, the directory is protected, so we don't have to check the
     * file.
     */
#endif
 
    /* Use an expansible buffer to accommodate any reasonable line length */
    initPQExpBuffer(&buf);
 
    while (!feof(fp) && !ferror(fp))
    {
        /* Make sure there's a reasonable amount of room in the buffer */
        if (!enlargePQExpBuffer(&buf, 128))
            break;
 
        /* Read some data, appending it to what we already have */
        if (fgets(buf.data + buf.len, buf.maxlen - buf.len, fp) == NULL)
            break;
        buf.len += strlen(buf.data + buf.len);
 
        /* If we don't yet have a whole line, loop around to read more */
        if (!(buf.len > 0 && buf.data[buf.len - 1] == '\n') && !feof(fp))
            continue;
 
        /* ignore comments */
        if (buf.data[0] != '#')
        {
            char       *t = buf.data;
            int         len;
 
            /* strip trailing newline and carriage return */
            len = pg_strip_crlf(t);
 
            if (len > 0 &&
                (t = pwdfMatchesString(t, hostname)) != NULL &&
                (t = pwdfMatchesString(t, port)) != NULL &&
                (t = pwdfMatchesString(t, dbname)) != NULL &&
                (t = pwdfMatchesString(t, username)) != NULL)
            {
                /* Found a match. */
                char       *ret,
                           *p1,
                           *p2;
 
                ret = strdup(t);
 
                fclose(fp);
                explicit_bzero(buf.data, buf.maxlen);
                termPQExpBuffer(&buf);
 
                if (!ret)
                {
                    /* Out of memory. XXX: an error message would be nice. */
                    return NULL;
                }
 
                /* De-escape password. */
                for (p1 = p2 = ret; *p1 != ':' && *p1 != '\0'; ++p1, ++p2)
                {
                    if (*p1 == '\\' && p1[1] != '\0')
                        ++p1;
                    *p2 = *p1;
                }
                *p2 = '\0';
 
                return ret;
            }
        }
 
        /* No match, reset buffer to prepare for next line. */
        buf.len = 0;
    }
 
    fclose(fp);
    explicit_bzero(buf.data, buf.maxlen);
    termPQExpBuffer(&buf);
    return NULL;
}

References buf, dbname, DEFAULT_PGSOCKET_DIR, DefaultHost, enlargePQExpBuffer(), explicit_bzero(), fprintf, fstat, hostname, initPQExpBuffer(), is_unixsock_path(), len, libpq_gettext, p2, pg_strip_crlf(), port, pwdfMatchesString(), S_IRWXG, S_IRWXO, S_ISREG, stat::st_mode, termPQExpBuffer(), and username.

Referenced by pqConnectOptions2().

pgpassfileWarning()

static void pgpassfileWarning ( PGconn *  conn )

static

Definition at line 7681 of file fe-connect.c.

{
    /* If it was 'invalid authorization', add pgpassfile mention */
    /* only works with >= 9.0 servers */
    if (conn->password_needed &&
        conn->connhost[conn->whichhost].password != NULL &&
        conn->result)
    {
        const char *sqlstate = PQresultErrorField(conn->result,
                                                  PG_DIAG_SQLSTATE);
 
        if (sqlstate && strcmp(sqlstate, ERRCODE_INVALID_PASSWORD) == 0)
            libpq_append_conn_error(conn, "password retrieved from file \"%s\"",
                                    conn->pgpassfile);
    }
}

References conn, pg_conn::connhost, ERRCODE_INVALID_PASSWORD, libpq_append_conn_error(), pg_conn_host::password, pg_conn::password_needed, PG_DIAG_SQLSTATE, pg_conn::pgpassfile, PQresultErrorField(), pg_conn::result, and pg_conn::whichhost.

Referenced by PQconnectPoll().

PQbackendPID()

int PQbackendPID

(

const PGconn *

conn

)

Definition at line 7302 of file fe-connect.c.

{
    if (!conn || conn->status != CONNECTION_OK)
        return 0;
    return conn->be_pid;
}

References pg_conn::be_pid, conn, CONNECTION_OK, and pg_conn::status.

Referenced by get_prompt(), libpqrcv_get_backend_pid(), main(), send_cancellable_query_impl(), and StartLogStreamer().

PQclientEncoding()

int PQclientEncoding

(

const PGconn *

conn

)

Definition at line 7356 of file fe-connect.c.

{
    if (!conn || conn->status != CONNECTION_OK)
        return -1;
    return conn->client_encoding;
}

References pg_conn::client_encoding, conn, CONNECTION_OK, and pg_conn::status.

Referenced by appendQualifiedRelation(), appendStringLiteralConn(), dblink_connect(), dblink_get_conn(), exec_command_encoding(), main(), processSQLNamePattern(), SendQuery(), setup_connection(), SyncVariables(), and vacuum_one_database().

pqClosePGconn()

void pqClosePGconn

(

PGconn *

conn

)

Definition at line 4893 of file fe-connect.c.

{
    /*
     * If possible, send Terminate message to close the connection politely.
     */
    sendTerminateConn(conn);
 
    /*
     * Must reset the blocking status so a possible reconnect will work.
     *
     * Don't call PQsetnonblocking() because it will fail if it's unable to
     * flush the connection.
     */
    conn->nonblocking = false;
 
    /*
     * Close the connection, reset all transient state, flush I/O buffers.
     * Note that this includes clearing conn's error state; we're no longer
     * interested in any failures associated with the old connection, and we
     * want a clean slate for any new connection attempt.
     */
    pqDropConnection(conn, true);
    conn->status = CONNECTION_BAD;  /* Well, not really _bad_ - just absent */
    conn->asyncStatus = PGASYNC_IDLE;
    conn->xactStatus = PQTRANS_IDLE;
    conn->pipelineStatus = PQ_PIPELINE_OFF;
    pqClearAsyncResult(conn);   /* deallocate result */
    pqClearConnErrorState(conn);
 
    /*
     * Release addrinfo, but since cancel requests never change their addrinfo
     * we don't do that. Otherwise we would have to rebuild it during a
     * PQcancelReset.
     */
    if (!conn->cancelRequest)
        release_conn_addrinfo(conn);
 
    /* Reset all state obtained from server, too */
    pqDropServerData(conn);
}

References pg_conn::asyncStatus, pg_conn::cancelRequest, conn, CONNECTION_BAD, pg_conn::nonblocking, PGASYNC_IDLE, pg_conn::pipelineStatus, PQ_PIPELINE_OFF, pqClearAsyncResult(), pqClearConnErrorState, pqDropConnection(), pqDropServerData(), PQTRANS_IDLE, release_conn_addrinfo(), sendTerminateConn(), pg_conn::status, and pg_conn::xactStatus.

Referenced by PQcancelReset(), PQfinish(), PQreset(), and PQresetStart().

PQconndefaults()

PQconninfoOption * PQconndefaults

(

void

)

Definition at line 1940 of file fe-connect.c.

{
    PQExpBufferData errorBuf;
    PQconninfoOption *connOptions;
 
    /* We don't actually report any errors here, but callees want a buffer */
    initPQExpBuffer(&errorBuf);
    if (PQExpBufferDataBroken(errorBuf))
        return NULL;            /* out of memory already :-( */
 
    connOptions = conninfo_init(&errorBuf);
    if (connOptions != NULL)
    {
        /* pass NULL errorBuf to ignore errors */
        if (!conninfo_add_defaults(connOptions, NULL))
        {
            PQconninfoFree(connOptions);
            connOptions = NULL;
        }
    }
 
    termPQExpBuffer(&errorBuf);
    return connOptions;
}

References conninfo_add_defaults(), conninfo_init(), initPQExpBuffer(), PQconninfoFree(), PQExpBufferDataBroken, and termPQExpBuffer().

Referenced by check_pghost_envvar(), dblink_fdw_validator(), do_connect(), get_connect_string(), GetDbnameFromConnectionOptions(), InitPgFdwOptions(), and main().

PQconnectdb()

PGconn * PQconnectdb

(

const char *

conninfo

)

Definition at line 753 of file fe-connect.c.

{
    PGconn     *conn = PQconnectStart(conninfo);
 
    if (conn && conn->status != CONNECTION_BAD)
        (void) pqConnectDBComplete(conn);
 
    return conn;
}

References conn, CONNECTION_BAD, pqConnectDBComplete(), PQconnectStart(), and pg_conn::status.

Referenced by connect_database(), get_db_conn(), and main().

pqConnectDBComplete()

int pqConnectDBComplete

(

PGconn *

conn

)

Definition at line 2529 of file fe-connect.c.

{
    PostgresPollingStatusType flag = PGRES_POLLING_WRITING;
    pg_usec_time_t end_time = -1;
    int         timeout = 0;
    int         last_whichhost = -2;    /* certainly different from whichhost */
    int         last_whichaddr = -2;    /* certainly different from whichaddr */
 
    if (conn == NULL || conn->status == CONNECTION_BAD)
        return 0;
 
    /*
     * Set up a time limit, if connect_timeout is greater than zero.
     */
    if (conn->connect_timeout != NULL)
    {
        if (!pqParseIntParam(conn->connect_timeout, &timeout, conn,
                             "connect_timeout"))
        {
            /* mark the connection as bad to report the parsing failure */
            conn->status = CONNECTION_BAD;
            return 0;
        }
    }
 
    for (;;)
    {
        int         ret = 0;
 
        /*
         * (Re)start the connect_timeout timer if it's active and we are
         * considering a different host than we were last time through.  If
         * we've already succeeded, though, needn't recalculate.
         */
        if (flag != PGRES_POLLING_OK &&
            timeout > 0 &&
            (conn->whichhost != last_whichhost ||
             conn->whichaddr != last_whichaddr))
        {
            end_time = PQgetCurrentTimeUSec() + (pg_usec_time_t) timeout * 1000000;
            last_whichhost = conn->whichhost;
            last_whichaddr = conn->whichaddr;
        }
 
        /*
         * Wait, if necessary.  Note that the initial state (just after
         * PQconnectStart) is to wait for the socket to select for writing.
         */
        switch (flag)
        {
            case PGRES_POLLING_OK:
                return 1;       /* success! */
 
            case PGRES_POLLING_READING:
                ret = pqWaitTimed(1, 0, conn, end_time);
                if (ret == -1)
                {
                    /* hard failure, eg select() problem, aborts everything */
                    conn->status = CONNECTION_BAD;
                    return 0;
                }
                break;
 
            case PGRES_POLLING_WRITING:
                ret = pqWaitTimed(0, 1, conn, end_time);
                if (ret == -1)
                {
                    /* hard failure, eg select() problem, aborts everything */
                    conn->status = CONNECTION_BAD;
                    return 0;
                }
                break;
 
            default:
                /* Just in case we failed to set it in PQconnectPoll */
                conn->status = CONNECTION_BAD;
                return 0;
        }
 
        if (ret == 1)           /* connect_timeout elapsed */
        {
            /*
             * Give up on current server/address, try the next one.
             */
            conn->try_next_addr = true;
            conn->status = CONNECTION_NEEDED;
        }
 
        /*
         * Now try to advance the state machine.
         */
        if (conn->cancelRequest)
            flag = PQcancelPoll((PGcancelConn *) conn);
        else
            flag = PQconnectPoll(conn);
    }
}

References pg_conn::cancelRequest, conn, pg_conn::connect_timeout, CONNECTION_BAD, CONNECTION_NEEDED, end_time, flag(), PGRES_POLLING_OK, PGRES_POLLING_READING, PGRES_POLLING_WRITING, PQcancelPoll(), PQconnectPoll(), PQgetCurrentTimeUSec(), pqParseIntParam(), pqWaitTimed(), pg_conn::status, pg_conn::try_next_addr, pg_conn::whichaddr, and pg_conn::whichhost.

Referenced by internal_ping(), PQcancelBlocking(), PQconnectdb(), PQconnectdbParams(), PQreset(), and PQsetdbLogin().

PQconnectdbParams()

PGconn * PQconnectdbParams	(	const char *const *	keywords,
		const char *const *	values,
		int	expand_dbname
	)

Definition at line 698 of file fe-connect.c.

{
    PGconn     *conn = PQconnectStartParams(keywords, values, expand_dbname);
 
    if (conn && conn->status != CONNECTION_BAD)
        (void) pqConnectDBComplete(conn);
 
    return conn;
}

References conn, CONNECTION_BAD, keywords, pqConnectDBComplete(), PQconnectStartParams(), pg_conn::status, and values.

Referenced by ConnectDatabase(), connectDatabase(), copy_connection(), doConnect(), ECPGconnect(), GetConnection(), main(), sql_conn(), and vacuumlo().

pqConnectDBStart()

int pqConnectDBStart

(

PGconn *

conn

)

Definition at line 2451 of file fe-connect.c.

{
    if (!conn)
        return 0;
 
    if (!conn->options_valid)
        goto connect_errReturn;
 
    /*
     * Check for bad linking to backend-internal versions of src/common
     * functions (see comments in link-canary.c for the reason we need this).
     * Nobody but developers should see this message, so we don't bother
     * translating it.
     */
    if (!pg_link_canary_is_frontend())
    {
        appendPQExpBufferStr(&conn->errorMessage,
                             "libpq is incorrectly linked to backend functions\n");
        goto connect_errReturn;
    }
 
    /* Ensure our buffers are empty */
    conn->inStart = conn->inCursor = conn->inEnd = 0;
    conn->outCount = 0;
 
    /*
     * Set up to try to connect to the first host.  (Setting whichhost = -1 is
     * a bit of a cheat, but PQconnectPoll will advance it to 0 before
     * anything else looks at it.)
     *
     * Cancel requests are special though, they should only try one host and
     * address, and these fields have already been set up in PQcancelCreate,
     * so leave these fields alone for cancel requests.
     */
    if (!conn->cancelRequest)
    {
        conn->whichhost = -1;
        conn->try_next_host = true;
        conn->try_next_addr = false;
    }
 
    conn->status = CONNECTION_NEEDED;
 
    /* Also reset the target_server_type state if needed */
    if (conn->target_server_type == SERVER_TYPE_PREFER_STANDBY_PASS2)
        conn->target_server_type = SERVER_TYPE_PREFER_STANDBY;
 
    /*
     * The code for processing CONNECTION_NEEDED state is in PQconnectPoll(),
     * so that it can easily be re-executed if needed again during the
     * asynchronous startup process.  However, we must run it once here,
     * because callers expect a success return from this routine to mean that
     * we are in PGRES_POLLING_WRITING connection state.
     */
    if (PQconnectPoll(conn) == PGRES_POLLING_WRITING)
        return 1;
 
connect_errReturn:
 
    /*
     * If we managed to open a socket, close it immediately rather than
     * waiting till PQfinish.  (The application cannot have gotten the socket
     * from PQsocket yet, so this doesn't risk breaking anything.)
     */
    pqDropConnection(conn, true);
    conn->status = CONNECTION_BAD;
    return 0;
}

References appendPQExpBufferStr(), pg_conn::cancelRequest, conn, CONNECTION_BAD, CONNECTION_NEEDED, pg_conn::errorMessage, pg_conn::inCursor, pg_conn::inEnd, pg_conn::inStart, pg_conn::options_valid, pg_conn::outCount, pg_link_canary_is_frontend(), PGRES_POLLING_WRITING, PQconnectPoll(), pqDropConnection(), SERVER_TYPE_PREFER_STANDBY, SERVER_TYPE_PREFER_STANDBY_PASS2, pg_conn::status, pg_conn::target_server_type, pg_conn::try_next_addr, pg_conn::try_next_host, and pg_conn::whichhost.

Referenced by PQcancelStart(), PQconnectStart(), PQconnectStartParams(), PQreset(), PQresetStart(), and PQsetdbLogin().

PQconnectionNeedsPassword()

int PQconnectionNeedsPassword

(

const PGconn *

conn

)

Definition at line 7319 of file fe-connect.c.

{
    char       *password;
 
    if (!conn)
        return false;
    password = PQpass(conn);
    if (conn->password_needed &&
        (password == NULL || password[0] == '\0'))
        return true;
    else
        return false;
}

References conn, password, pg_conn::password_needed, and PQpass().

Referenced by ConnectDatabase(), connectDatabase(), do_connect(), doConnect(), GetConnection(), main(), sql_conn(), and vacuumlo().

PQconnectionUsedGSSAPI()

int PQconnectionUsedGSSAPI

(

const PGconn *

conn

)

Definition at line 7345 of file fe-connect.c.

{
    if (!conn)
        return false;
    if (conn->gssapi_used)
        return true;
    else
        return false;
}

References conn, and pg_conn::gssapi_used.

Referenced by dblink_security_check(), and pgfdw_security_check().

PQconnectionUsedPassword()

int PQconnectionUsedPassword

(

const PGconn *

conn

)

Definition at line 7334 of file fe-connect.c.

{
    if (!conn)
        return false;
    if (conn->password_needed)
        return true;
    else
        return false;
}

References conn, and pg_conn::password_needed.

Referenced by ConnectDatabase(), dblink_security_check(), libpqrcv_connect(), and pgfdw_security_check().

pqConnectOptions2()

bool pqConnectOptions2

(

PGconn *

conn

)

Definition at line 1129 of file fe-connect.c.

{
    int         i;
 
    /*
     * Allocate memory for details about each host to which we might possibly
     * try to connect.  For that, count the number of elements in the hostaddr
     * or host options.  If neither is given, assume one host.
     */
    conn->whichhost = 0;
    if (conn->pghostaddr && conn->pghostaddr[0] != '\0')
        conn->nconnhost = count_comma_separated_elems(conn->pghostaddr);
    else if (conn->pghost && conn->pghost[0] != '\0')
        conn->nconnhost = count_comma_separated_elems(conn->pghost);
    else
        conn->nconnhost = 1;
    conn->connhost = (pg_conn_host *)
        calloc(conn->nconnhost, sizeof(pg_conn_host));
    if (conn->connhost == NULL)
        goto oom_error;
 
    /*
     * We now have one pg_conn_host structure per possible host.  Fill in the
     * host and hostaddr fields for each, by splitting the parameter strings.
     */
    if (conn->pghostaddr != NULL && conn->pghostaddr[0] != '\0')
    {
        char       *s = conn->pghostaddr;
        bool        more = true;
 
        for (i = 0; i < conn->nconnhost && more; i++)
        {
            conn->connhost[i].hostaddr = parse_comma_separated_list(&s, &more);
            if (conn->connhost[i].hostaddr == NULL)
                goto oom_error;
        }
 
        /*
         * If hostaddr was given, the array was allocated according to the
         * number of elements in the hostaddr list, so it really should be the
         * right size.
         */
        Assert(!more);
        Assert(i == conn->nconnhost);
    }
 
    if (conn->pghost != NULL && conn->pghost[0] != '\0')
    {
        char       *s = conn->pghost;
        bool        more = true;
 
        for (i = 0; i < conn->nconnhost && more; i++)
        {
            conn->connhost[i].host = parse_comma_separated_list(&s, &more);
            if (conn->connhost[i].host == NULL)
                goto oom_error;
        }
 
        /* Check for wrong number of host items. */
        if (more || i != conn->nconnhost)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "could not match %d host names to %d hostaddr values",
                                    count_comma_separated_elems(conn->pghost), conn->nconnhost);
            return false;
        }
    }
 
    /*
     * Now, for each host slot, identify the type of address spec, and fill in
     * the default address if nothing was given.
     */
    for (i = 0; i < conn->nconnhost; i++)
    {
        pg_conn_host *ch = &conn->connhost[i];
 
        if (ch->hostaddr != NULL && ch->hostaddr[0] != '\0')
            ch->type = CHT_HOST_ADDRESS;
        else if (ch->host != NULL && ch->host[0] != '\0')
        {
            ch->type = CHT_HOST_NAME;
            if (is_unixsock_path(ch->host))
                ch->type = CHT_UNIX_SOCKET;
        }
        else
        {
            free(ch->host);
 
            /*
             * This bit selects the default host location.  If you change
             * this, see also pg_regress.
             */
            if (DEFAULT_PGSOCKET_DIR[0])
            {
                ch->host = strdup(DEFAULT_PGSOCKET_DIR);
                ch->type = CHT_UNIX_SOCKET;
            }
            else
            {
                ch->host = strdup(DefaultHost);
                ch->type = CHT_HOST_NAME;
            }
            if (ch->host == NULL)
                goto oom_error;
        }
    }
 
    /*
     * Next, work out the port number corresponding to each host name.
     *
     * Note: unlike the above for host names, this could leave the port fields
     * as null or empty strings.  We will substitute DEF_PGPORT whenever we
     * read such a port field.
     */
    if (conn->pgport != NULL && conn->pgport[0] != '\0')
    {
        char       *s = conn->pgport;
        bool        more = true;
 
        for (i = 0; i < conn->nconnhost && more; i++)
        {
            conn->connhost[i].port = parse_comma_separated_list(&s, &more);
            if (conn->connhost[i].port == NULL)
                goto oom_error;
        }
 
        /*
         * If exactly one port was given, use it for every host.  Otherwise,
         * there must be exactly as many ports as there were hosts.
         */
        if (i == 1 && !more)
        {
            for (i = 1; i < conn->nconnhost; i++)
            {
                conn->connhost[i].port = strdup(conn->connhost[0].port);
                if (conn->connhost[i].port == NULL)
                    goto oom_error;
            }
        }
        else if (more || i != conn->nconnhost)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "could not match %d port numbers to %d hosts",
                                    count_comma_separated_elems(conn->pgport), conn->nconnhost);
            return false;
        }
    }
 
    /*
     * If user name was not given, fetch it.  (Most likely, the fetch will
     * fail, since the only way we get here is if pg_fe_getauthname() failed
     * during conninfo_add_defaults().  But now we want an error message.)
     */
    if (conn->pguser == NULL || conn->pguser[0] == '\0')
    {
        free(conn->pguser);
        conn->pguser = pg_fe_getauthname(&conn->errorMessage);
        if (!conn->pguser)
        {
            conn->status = CONNECTION_BAD;
            return false;
        }
    }
 
    /*
     * If database name was not given, default it to equal user name
     */
    if (conn->dbName == NULL || conn->dbName[0] == '\0')
    {
        free(conn->dbName);
        conn->dbName = strdup(conn->pguser);
        if (!conn->dbName)
            goto oom_error;
    }
 
    /*
     * If password was not given, try to look it up in password file.  Note
     * that the result might be different for each host/port pair.
     */
    if (conn->pgpass == NULL || conn->pgpass[0] == '\0')
    {
        /* If password file wasn't specified, use ~/PGPASSFILE */
        if (conn->pgpassfile == NULL || conn->pgpassfile[0] == '\0')
        {
            char        homedir[MAXPGPATH];
 
            if (pqGetHomeDirectory(homedir, sizeof(homedir)))
            {
                free(conn->pgpassfile);
                conn->pgpassfile = malloc(MAXPGPATH);
                if (!conn->pgpassfile)
                    goto oom_error;
                snprintf(conn->pgpassfile, MAXPGPATH, "%s/%s",
                         homedir, PGPASSFILE);
            }
        }
 
        if (conn->pgpassfile != NULL && conn->pgpassfile[0] != '\0')
        {
            for (i = 0; i < conn->nconnhost; i++)
            {
                /*
                 * Try to get a password for this host from file.  We use host
                 * for the hostname search key if given, else hostaddr (at
                 * least one of them is guaranteed nonempty by now).
                 */
                const char *pwhost = conn->connhost[i].host;
 
                if (pwhost == NULL || pwhost[0] == '\0')
                    pwhost = conn->connhost[i].hostaddr;
 
                conn->connhost[i].password =
                    passwordFromFile(pwhost,
                                     conn->connhost[i].port,
                                     conn->dbName,
                                     conn->pguser,
                                     conn->pgpassfile);
            }
        }
    }
 
    /*
     * parse and validate require_auth option
     */
    if (conn->require_auth && conn->require_auth[0])
    {
        char       *s = conn->require_auth;
        bool        first,
                    more;
        bool        negated = false;
 
        /*
         * By default, start from an empty set of allowed options and add to
         * it.
         */
        conn->auth_required = true;
        conn->allowed_auth_methods = 0;
 
        for (first = true, more = true; more; first = false)
        {
            char       *method,
                       *part;
            uint32      bits;
 
            part = parse_comma_separated_list(&s, &more);
            if (part == NULL)
                goto oom_error;
 
            /*
             * Check for negation, e.g. '!password'. If one element is
             * negated, they all have to be.
             */
            method = part;
            if (*method == '!')
            {
                if (first)
                {
                    /*
                     * Switch to a permissive set of allowed options, and
                     * subtract from it.
                     */
                    conn->auth_required = false;
                    conn->allowed_auth_methods = -1;
                }
                else if (!negated)
                {
                    conn->status = CONNECTION_BAD;
                    libpq_append_conn_error(conn, "negative require_auth method \"%s\" cannot be mixed with non-negative methods",
                                            method);
 
                    free(part);
                    return false;
                }
 
                negated = true;
                method++;
            }
            else if (negated)
            {
                conn->status = CONNECTION_BAD;
                libpq_append_conn_error(conn, "require_auth method \"%s\" cannot be mixed with negative methods",
                                        method);
 
                free(part);
                return false;
            }
 
            if (strcmp(method, "password") == 0)
            {
                bits = (1 << AUTH_REQ_PASSWORD);
            }
            else if (strcmp(method, "md5") == 0)
            {
                bits = (1 << AUTH_REQ_MD5);
            }
            else if (strcmp(method, "gss") == 0)
            {
                bits = (1 << AUTH_REQ_GSS);
                bits |= (1 << AUTH_REQ_GSS_CONT);
            }
            else if (strcmp(method, "sspi") == 0)
            {
                bits = (1 << AUTH_REQ_SSPI);
                bits |= (1 << AUTH_REQ_GSS_CONT);
            }
            else if (strcmp(method, "scram-sha-256") == 0)
            {
                /* This currently assumes that SCRAM is the only SASL method. */
                bits = (1 << AUTH_REQ_SASL);
                bits |= (1 << AUTH_REQ_SASL_CONT);
                bits |= (1 << AUTH_REQ_SASL_FIN);
            }
            else if (strcmp(method, "none") == 0)
            {
                /*
                 * Special case: let the user explicitly allow (or disallow)
                 * connections where the server does not send an explicit
                 * authentication challenge, such as "trust" and "cert" auth.
                 */
                if (negated)    /* "!none" */
                {
                    if (conn->auth_required)
                        goto duplicate;
 
                    conn->auth_required = true;
                }
                else            /* "none" */
                {
                    if (!conn->auth_required)
                        goto duplicate;
 
                    conn->auth_required = false;
                }
 
                free(part);
                continue;       /* avoid the bitmask manipulation below */
            }
            else
            {
                conn->status = CONNECTION_BAD;
                libpq_append_conn_error(conn, "invalid %s value: \"%s\"",
                                        "require_auth", method);
 
                free(part);
                return false;
            }
 
            /* Update the bitmask. */
            if (negated)
            {
                if ((conn->allowed_auth_methods & bits) == 0)
                    goto duplicate;
 
                conn->allowed_auth_methods &= ~bits;
            }
            else
            {
                if ((conn->allowed_auth_methods & bits) == bits)
                    goto duplicate;
 
                conn->allowed_auth_methods |= bits;
            }
 
            free(part);
            continue;
 
    duplicate:
 
            /*
             * A duplicated method probably indicates a typo in a setting
             * where typos are extremely risky.
             */
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "require_auth method \"%s\" is specified more than once",
                                    part);
 
            free(part);
            return false;
        }
    }
 
    /*
     * validate channel_binding option
     */
    if (conn->channel_binding)
    {
        if (strcmp(conn->channel_binding, "disable") != 0
            && strcmp(conn->channel_binding, "prefer") != 0
            && strcmp(conn->channel_binding, "require") != 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "invalid %s value: \"%s\"",
                                    "channel_binding", conn->channel_binding);
            return false;
        }
    }
    else
    {
        conn->channel_binding = strdup(DefaultChannelBinding);
        if (!conn->channel_binding)
            goto oom_error;
    }
 
#ifndef USE_SSL
 
    /*
     * sslrootcert=system is not supported. Since setting this changes the
     * default sslmode, check this _before_ we validate sslmode, to avoid
     * confusing the user with errors for an option they may not have set.
     */
    if (conn->sslrootcert
        && strcmp(conn->sslrootcert, "system") == 0)
    {
        conn->status = CONNECTION_BAD;
        libpq_append_conn_error(conn, "%s value \"%s\" invalid when SSL support is not compiled in",
                                "sslrootcert", conn->sslrootcert);
        return false;
    }
#endif
 
    /*
     * validate sslmode option
     */
    if (conn->sslmode)
    {
        if (strcmp(conn->sslmode, "disable") != 0
            && strcmp(conn->sslmode, "allow") != 0
            && strcmp(conn->sslmode, "prefer") != 0
            && strcmp(conn->sslmode, "require") != 0
            && strcmp(conn->sslmode, "verify-ca") != 0
            && strcmp(conn->sslmode, "verify-full") != 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "invalid %s value: \"%s\"",
                                    "sslmode", conn->sslmode);
            return false;
        }
 
#ifndef USE_SSL
        switch (conn->sslmode[0])
        {
            case 'a':           /* "allow" */
            case 'p':           /* "prefer" */
 
                /*
                 * warn user that an SSL connection will never be negotiated
                 * since SSL was not compiled in?
                 */
                break;
 
            case 'r':           /* "require" */
            case 'v':           /* "verify-ca" or "verify-full" */
                conn->status = CONNECTION_BAD;
                libpq_append_conn_error(conn, "%s value \"%s\" invalid when SSL support is not compiled in",
                                        "sslmode", conn->sslmode);
                return false;
        }
#endif
    }
    else
    {
        conn->sslmode = strdup(DefaultSSLMode);
        if (!conn->sslmode)
            goto oom_error;
    }
 
    /*
     * validate sslnegotiation option, default is "postgres" for the postgres
     * style negotiated connection with an extra round trip but more options.
     */
    if (conn->sslnegotiation)
    {
        if (strcmp(conn->sslnegotiation, "postgres") != 0
            && strcmp(conn->sslnegotiation, "direct") != 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "invalid %s value: \"%s\"",
                                    "sslnegotiation", conn->sslnegotiation);
            return false;
        }
 
#ifndef USE_SSL
        if (conn->sslnegotiation[0] != 'p')
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "%s value \"%s\" invalid when SSL support is not compiled in",
                                    "sslnegotiation", conn->sslnegotiation);
            return false;
        }
#endif
 
        /*
         * Don't allow direct SSL negotiation with sslmode='prefer', because
         * that poses a risk of unintentional fallback to plaintext connection
         * when connecting to a pre-v17 server that does not support direct
         * SSL connections. To keep things simple, don't allow it with
         * sslmode='allow' or sslmode='disable' either. If a user goes through
         * the trouble of setting sslnegotiation='direct', they probably
         * intend to use SSL, and sslmode=disable or allow is probably a user
         * user mistake anyway.
         */
        if (conn->sslnegotiation[0] == 'd' &&
            conn->sslmode[0] != 'r' && conn->sslmode[0] != 'v')
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "weak sslmode \"%s\" may not be used with sslnegotiation=direct (use \"require\", \"verify-ca\", or \"verify-full\")",
                                    conn->sslmode);
            return false;
        }
    }
    else
    {
        conn->sslnegotiation = strdup(DefaultSSLNegotiation);
        if (!conn->sslnegotiation)
            goto oom_error;
    }
 
#ifdef USE_SSL
 
    /*
     * If sslrootcert=system, make sure our chosen sslmode is compatible.
     */
    if (conn->sslrootcert
        && strcmp(conn->sslrootcert, "system") == 0
        && strcmp(conn->sslmode, "verify-full") != 0)
    {
        conn->status = CONNECTION_BAD;
        libpq_append_conn_error(conn, "weak sslmode \"%s\" may not be used with sslrootcert=system (use \"verify-full\")",
                                conn->sslmode);
        return false;
    }
#endif
 
    /*
     * Validate TLS protocol versions for ssl_min_protocol_version and
     * ssl_max_protocol_version.
     */
    if (!sslVerifyProtocolVersion(conn->ssl_min_protocol_version))
    {
        conn->status = CONNECTION_BAD;
        libpq_append_conn_error(conn, "invalid \"%s\" value: \"%s\"",
                                "ssl_min_protocol_version",
                                conn->ssl_min_protocol_version);
        return false;
    }
    if (!sslVerifyProtocolVersion(conn->ssl_max_protocol_version))
    {
        conn->status = CONNECTION_BAD;
        libpq_append_conn_error(conn, "invalid \"%s\" value: \"%s\"",
                                "ssl_max_protocol_version",
                                conn->ssl_max_protocol_version);
        return false;
    }
 
    /*
     * Check if the range of SSL protocols defined is correct.  This is done
     * at this early step because this is independent of the SSL
     * implementation used, and this avoids unnecessary cycles with an
     * already-built SSL context when the connection is being established, as
     * it would be doomed anyway.
     */
    if (!sslVerifyProtocolRange(conn->ssl_min_protocol_version,
                                conn->ssl_max_protocol_version))
    {
        conn->status = CONNECTION_BAD;
        libpq_append_conn_error(conn, "invalid SSL protocol version range");
        return false;
    }
 
    /*
     * validate sslcertmode option
     */
    if (conn->sslcertmode)
    {
        if (strcmp(conn->sslcertmode, "disable") != 0 &&
            strcmp(conn->sslcertmode, "allow") != 0 &&
            strcmp(conn->sslcertmode, "require") != 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "invalid %s value: \"%s\"",
                                    "sslcertmode", conn->sslcertmode);
            return false;
        }
#ifndef USE_SSL
        if (strcmp(conn->sslcertmode, "require") == 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "%s value \"%s\" invalid when SSL support is not compiled in",
                                    "sslcertmode", conn->sslcertmode);
            return false;
        }
#endif
#ifndef HAVE_SSL_CTX_SET_CERT_CB
 
        /*
         * Without a certificate callback, the current implementation can't
         * figure out if a certificate was actually requested, so "require" is
         * useless.
         */
        if (strcmp(conn->sslcertmode, "require") == 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "%s value \"%s\" is not supported (check OpenSSL version)",
                                    "sslcertmode", conn->sslcertmode);
            return false;
        }
#endif
    }
    else
    {
        conn->sslcertmode = strdup(DefaultSSLCertMode);
        if (!conn->sslcertmode)
            goto oom_error;
    }
 
    /*
     * validate gssencmode option
     */
    if (conn->gssencmode)
    {
        if (strcmp(conn->gssencmode, "disable") != 0 &&
            strcmp(conn->gssencmode, "prefer") != 0 &&
            strcmp(conn->gssencmode, "require") != 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "invalid %s value: \"%s\"", "gssencmode", conn->gssencmode);
            return false;
        }
#ifndef ENABLE_GSS
        if (strcmp(conn->gssencmode, "require") == 0)
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "gssencmode value \"%s\" invalid when GSSAPI support is not compiled in",
                                    conn->gssencmode);
            return false;
        }
#endif
    }
    else
    {
        conn->gssencmode = strdup(DefaultGSSMode);
        if (!conn->gssencmode)
            goto oom_error;
    }
 
    /*
     * validate target_session_attrs option, and set target_server_type
     */
    if (conn->target_session_attrs)
    {
        if (strcmp(conn->target_session_attrs, "any") == 0)
            conn->target_server_type = SERVER_TYPE_ANY;
        else if (strcmp(conn->target_session_attrs, "read-write") == 0)
            conn->target_server_type = SERVER_TYPE_READ_WRITE;
        else if (strcmp(conn->target_session_attrs, "read-only") == 0)
            conn->target_server_type = SERVER_TYPE_READ_ONLY;
        else if (strcmp(conn->target_session_attrs, "primary") == 0)
            conn->target_server_type = SERVER_TYPE_PRIMARY;
        else if (strcmp(conn->target_session_attrs, "standby") == 0)
            conn->target_server_type = SERVER_TYPE_STANDBY;
        else if (strcmp(conn->target_session_attrs, "prefer-standby") == 0)
            conn->target_server_type = SERVER_TYPE_PREFER_STANDBY;
        else
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "invalid %s value: \"%s\"",
                                    "target_session_attrs",
                                    conn->target_session_attrs);
            return false;
        }
    }
    else
        conn->target_server_type = SERVER_TYPE_ANY;
 
    if (conn->scram_client_key)
    {
        int         len;
 
        len = pg_b64_dec_len(strlen(conn->scram_client_key));
        conn->scram_client_key_binary = malloc(len);
        if (!conn->scram_client_key_binary)
            goto oom_error;
        len = pg_b64_decode(conn->scram_client_key, strlen(conn->scram_client_key),
                            conn->scram_client_key_binary, len);
        if (len < 0)
        {
            libpq_append_conn_error(conn, "invalid SCRAM client key");
            free(conn->scram_client_key_binary);
            return false;
        }
        if (len != SCRAM_MAX_KEY_LEN)
        {
            libpq_append_conn_error(conn, "invalid SCRAM client key length: %d", len);
            free(conn->scram_client_key_binary);
            return false;
        }
        conn->scram_client_key_len = len;
    }
 
    if (conn->scram_server_key)
    {
        int         len;
 
        len = pg_b64_dec_len(strlen(conn->scram_server_key));
        conn->scram_server_key_binary = malloc(len);
        if (!conn->scram_server_key_binary)
            goto oom_error;
        len = pg_b64_decode(conn->scram_server_key, strlen(conn->scram_server_key),
                            conn->scram_server_key_binary, len);
        if (len < 0)
        {
            libpq_append_conn_error(conn, "invalid SCRAM server key");
            free(conn->scram_server_key_binary);
            return false;
        }
        if (len != SCRAM_MAX_KEY_LEN)
        {
            libpq_append_conn_error(conn, "invalid SCRAM server key length: %d", len);
            free(conn->scram_server_key_binary);
            return false;
        }
        conn->scram_server_key_len = len;
    }
 
    /*
     * validate load_balance_hosts option, and set load_balance_type
     */
    if (conn->load_balance_hosts)
    {
        if (strcmp(conn->load_balance_hosts, "disable") == 0)
            conn->load_balance_type = LOAD_BALANCE_DISABLE;
        else if (strcmp(conn->load_balance_hosts, "random") == 0)
            conn->load_balance_type = LOAD_BALANCE_RANDOM;
        else
        {
            conn->status = CONNECTION_BAD;
            libpq_append_conn_error(conn, "invalid %s value: \"%s\"",
                                    "load_balance_hosts",
                                    conn->load_balance_hosts);
            return false;
        }
    }
    else
        conn->load_balance_type = LOAD_BALANCE_DISABLE;
 
    if (conn->load_balance_type == LOAD_BALANCE_RANDOM)
    {
        libpq_prng_init(conn);
 
        /*
         * This is the "inside-out" variant of the Fisher-Yates shuffle
         * algorithm. Notionally, we append each new value to the array and
         * then swap it with a randomly-chosen array element (possibly
         * including itself, else we fail to generate permutations with the
         * last integer last).  The swap step can be optimized by combining it
         * with the insertion.
         */
        for (i = 1; i < conn->nconnhost; i++)
        {
            int         j = pg_prng_uint64_range(&conn->prng_state, 0, i);
            pg_conn_host temp = conn->connhost[j];
 
            conn->connhost[j] = conn->connhost[i];
            conn->connhost[i] = temp;
        }
    }
 
    /*
     * Resolve special "auto" client_encoding from the locale
     */
    if (conn->client_encoding_initial &&
        strcmp(conn->client_encoding_initial, "auto") == 0)
    {
        free(conn->client_encoding_initial);
        conn->client_encoding_initial = strdup(pg_encoding_to_char(pg_get_encoding_from_locale(NULL, true)));
        if (!conn->client_encoding_initial)
            goto oom_error;
    }
 
    /*
     * Only if we get this far is it appropriate to try to connect. (We need a
     * state flag, rather than just the boolean result of this function, in
     * case someone tries to PQreset() the PGconn.)
     */
    conn->options_valid = true;
 
    return true;
 
oom_error:
    conn->status = CONNECTION_BAD;
    libpq_append_conn_error(conn, "out of memory");
    return false;
}

References pg_conn::allowed_auth_methods, Assert, AUTH_REQ_GSS, AUTH_REQ_GSS_CONT, AUTH_REQ_MD5, AUTH_REQ_PASSWORD, AUTH_REQ_SASL, AUTH_REQ_SASL_CONT, AUTH_REQ_SASL_FIN, AUTH_REQ_SSPI, pg_conn::auth_required, calloc, pg_conn::channel_binding, CHT_HOST_ADDRESS, CHT_HOST_NAME, CHT_UNIX_SOCKET, pg_conn::client_encoding_initial, conn, CONNECTION_BAD, pg_conn::connhost, count_comma_separated_elems(), pg_conn::dbName, DEFAULT_PGSOCKET_DIR, DefaultChannelBinding, DefaultGSSMode, DefaultHost, DefaultSSLCertMode, DefaultSSLMode, DefaultSSLNegotiation, pg_conn::errorMessage, free, pg_conn::gssencmode, pg_conn_host::host, pg_conn_host::hostaddr, i, is_unixsock_path(), j, len, libpq_append_conn_error(), libpq_prng_init(), LOAD_BALANCE_DISABLE, pg_conn::load_balance_hosts, LOAD_BALANCE_RANDOM, pg_conn::load_balance_type, malloc, MAXPGPATH, pg_conn::nconnhost, pg_conn::options_valid, parse_comma_separated_list(), pg_conn_host::password, passwordFromFile(), pg_b64_dec_len(), pg_b64_decode(), pg_encoding_to_char, pg_fe_getauthname(), pg_get_encoding_from_locale(), pg_prng_uint64_range(), pg_conn::pghost, pg_conn::pghostaddr, pg_conn::pgpass, PGPASSFILE, pg_conn::pgpassfile, pg_conn::pgport, pg_conn::pguser, pg_conn_host::port, pqGetHomeDirectory(), pg_conn::prng_state, pg_conn::require_auth, pg_conn::scram_client_key, pg_conn::scram_client_key_binary, pg_conn::scram_client_key_len, SCRAM_MAX_KEY_LEN, pg_conn::scram_server_key, pg_conn::scram_server_key_binary, pg_conn::scram_server_key_len, SERVER_TYPE_ANY, SERVER_TYPE_PREFER_STANDBY, SERVER_TYPE_PRIMARY, SERVER_TYPE_READ_ONLY, SERVER_TYPE_READ_WRITE, SERVER_TYPE_STANDBY, snprintf, pg_conn::ssl_max_protocol_version, pg_conn::ssl_min_protocol_version, pg_conn::sslcertmode, pg_conn::sslmode, pg_conn::sslnegotiation, pg_conn::sslrootcert, sslVerifyProtocolRange(), sslVerifyProtocolVersion(), pg_conn::status, pg_conn::target_server_type, pg_conn::target_session_attrs, pg_conn_host::type, and pg_conn::whichhost.

Referenced by PQcancelCreate(), PQconnectStart(), PQconnectStartParams(), and PQsetdbLogin().

PQconnectPoll()

PostgresPollingStatusType PQconnectPoll

(

PGconn *

conn

)

Definition at line 2655 of file fe-connect.c.

{
    bool        reset_connection_state_machine = false;
    bool        need_new_connection = false;
    PGresult   *res;
    char        sebuf[PG_STRERROR_R_BUFLEN];
    int         optval;
 
    if (conn == NULL)
        return PGRES_POLLING_FAILED;
 
    /* Get the new data */
    switch (conn->status)
    {
            /*
             * We really shouldn't have been polled in these two cases, but we
             * can handle it.
             */
        case CONNECTION_BAD:
            return PGRES_POLLING_FAILED;
        case CONNECTION_OK:
            return PGRES_POLLING_OK;
 
            /* These are reading states */
        case CONNECTION_AWAITING_RESPONSE:
        case CONNECTION_AUTH_OK:
        case CONNECTION_CHECK_WRITABLE:
        case CONNECTION_CONSUME:
        case CONNECTION_CHECK_STANDBY:
            {
                /* Load waiting data */
                int         n = pqReadData(conn);
 
                if (n < 0)
                    goto error_return;
                if (n == 0)
                    return PGRES_POLLING_READING;
 
                break;
            }
 
            /* These are writing states, so we just proceed. */
        case CONNECTION_STARTED:
        case CONNECTION_MADE:
            break;
 
            /* Special cases: proceed without waiting. */
        case CONNECTION_SSL_STARTUP:
        case CONNECTION_NEEDED:
        case CONNECTION_GSS_STARTUP:
        case CONNECTION_CHECK_TARGET:
            break;
 
        default:
            libpq_append_conn_error(conn, "invalid connection state, probably indicative of memory corruption");
            goto error_return;
    }
 
 
keep_going:                     /* We will come back to here until there is
                                 * nothing left to do. */
 
    /* Time to advance to next address, or next host if no more addresses? */
    if (conn->try_next_addr)
    {
        if (conn->whichaddr < conn->naddr)
        {
            conn->whichaddr++;
            reset_connection_state_machine = true;
        }
        else
            conn->try_next_host = true;
        conn->try_next_addr = false;
    }
 
    /* Time to advance to next connhost[] entry? */
    if (conn->try_next_host)
    {
        pg_conn_host *ch;
        struct addrinfo hint;
        struct addrinfo *addrlist;
        int         thisport;
        int         ret;
        char        portstr[MAXPGPATH];
 
        if (conn->whichhost + 1 < conn->nconnhost)
            conn->whichhost++;
        else
        {
            /*
             * Oops, no more hosts.
             *
             * If we are trying to connect in "prefer-standby" mode, then drop
             * the standby requirement and start over. Don't do this for
             * cancel requests though, since we are certain the list of
             * servers won't change as the target_server_type option is not
             * applicable to those connections.
             *
             * Otherwise, an appropriate error message is already set up, so
             * we just need to set the right status.
             */
            if (conn->target_server_type == SERVER_TYPE_PREFER_STANDBY &&
                conn->nconnhost > 0 &&
                !conn->cancelRequest)
            {
                conn->target_server_type = SERVER_TYPE_PREFER_STANDBY_PASS2;
                conn->whichhost = 0;
            }
            else
                goto error_return;
        }
 
        /* Drop any address info for previous host */
        release_conn_addrinfo(conn);
 
        /*
         * Look up info for the new host.  On failure, log the problem in
         * conn->errorMessage, then loop around to try the next host.  (Note
         * we don't clear try_next_host until we've succeeded.)
         */
        ch = &conn->connhost[conn->whichhost];
 
        /* Initialize hint structure */
        MemSet(&hint, 0, sizeof(hint));
        hint.ai_socktype = SOCK_STREAM;
        hint.ai_family = AF_UNSPEC;
 
        /* Figure out the port number we're going to use. */
        if (ch->port == NULL || ch->port[0] == '\0')
            thisport = DEF_PGPORT;
        else
        {
            if (!pqParseIntParam(ch->port, &thisport, conn, "port"))
                goto error_return;
 
            if (thisport < 1 || thisport > 65535)
            {
                libpq_append_conn_error(conn, "invalid port number: \"%s\"", ch->port);
                goto keep_going;
            }
        }
        snprintf(portstr, sizeof(portstr), "%d", thisport);
 
        /* Use pg_getaddrinfo_all() to resolve the address */
        switch (ch->type)
        {
            case CHT_HOST_NAME:
                ret = pg_getaddrinfo_all(ch->host, portstr, &hint,
                                         &addrlist);
                if (ret || !addrlist)
                {
                    libpq_append_conn_error(conn, "could not translate host name \"%s\" to address: %s",
                                            ch->host, gai_strerror(ret));
                    goto keep_going;
                }
                break;
 
            case CHT_HOST_ADDRESS:
                hint.ai_flags = AI_NUMERICHOST;
                ret = pg_getaddrinfo_all(ch->hostaddr, portstr, &hint,
                                         &addrlist);
                if (ret || !addrlist)
                {
                    libpq_append_conn_error(conn, "could not parse network address \"%s\": %s",
                                            ch->hostaddr, gai_strerror(ret));
                    goto keep_going;
                }
                break;
 
            case CHT_UNIX_SOCKET:
                hint.ai_family = AF_UNIX;
                UNIXSOCK_PATH(portstr, thisport, ch->host);
                if (strlen(portstr) >= UNIXSOCK_PATH_BUFLEN)
                {
                    libpq_append_conn_error(conn, "Unix-domain socket path \"%s\" is too long (maximum %d bytes)",
                                            portstr,
                                            (int) (UNIXSOCK_PATH_BUFLEN - 1));
                    goto keep_going;
                }
 
                /*
                 * NULL hostname tells pg_getaddrinfo_all to parse the service
                 * name as a Unix-domain socket path.
                 */
                ret = pg_getaddrinfo_all(NULL, portstr, &hint,
                                         &addrlist);
                if (ret || !addrlist)
                {
                    libpq_append_conn_error(conn, "could not translate Unix-domain socket path \"%s\" to address: %s",
                                            portstr, gai_strerror(ret));
                    goto keep_going;
                }
                break;
        }
 
        /*
         * Store a copy of the addrlist in private memory so we can perform
         * randomization for load balancing.
         */
        ret = store_conn_addrinfo(conn, addrlist);
        pg_freeaddrinfo_all(hint.ai_family, addrlist);
        if (ret)
            goto error_return;  /* message already logged */
 
        /*
         * If random load balancing is enabled we shuffle the addresses.
         */
        if (conn->load_balance_type == LOAD_BALANCE_RANDOM)
        {
            /*
             * This is the "inside-out" variant of the Fisher-Yates shuffle
             * algorithm. Notionally, we append each new value to the array
             * and then swap it with a randomly-chosen array element (possibly
             * including itself, else we fail to generate permutations with
             * the last integer last).  The swap step can be optimized by
             * combining it with the insertion.
             *
             * We don't need to initialize conn->prng_state here, because that
             * already happened in pqConnectOptions2.
             */
            for (int i = 1; i < conn->naddr; i++)
            {
                int         j = pg_prng_uint64_range(&conn->prng_state, 0, i);
                AddrInfo    temp = conn->addr[j];
 
                conn->addr[j] = conn->addr[i];
                conn->addr[i] = temp;
            }
        }
 
        reset_connection_state_machine = true;
        conn->try_next_host = false;
    }
 
    /* Reset connection state machine? */
    if (reset_connection_state_machine)
    {
        /*
         * (Re) initialize our connection control variables for a set of
         * connection attempts to a single server address.  These variables
         * must persist across individual connection attempts, but we must
         * reset them when we start to consider a new server.
         */
        conn->pversion = PG_PROTOCOL(3, 0);
        conn->send_appname = true;
        conn->failed_enc_methods = 0;
        conn->current_enc_method = 0;
        conn->allowed_enc_methods = 0;
        reset_connection_state_machine = false;
        need_new_connection = true;
    }
 
    /* Force a new connection (perhaps to the same server as before)? */
    if (need_new_connection)
    {
        /* Drop any existing connection */
        pqDropConnection(conn, true);
 
        /* Reset all state obtained from old server */
        pqDropServerData(conn);
 
        /* Drop any PGresult we might have, too */
        conn->asyncStatus = PGASYNC_IDLE;
        conn->xactStatus = PQTRANS_IDLE;
        conn->pipelineStatus = PQ_PIPELINE_OFF;
        pqClearAsyncResult(conn);
 
        /* Reset conn->status to put the state machine in the right state */
        conn->status = CONNECTION_NEEDED;
 
        need_new_connection = false;
    }
 
    /*
     * Decide what to do next, if server rejects SSL or GSS negotiation, but
     * the connection is still valid.  If there are no options left, error out
     * with 'msg'.
     */
#define ENCRYPTION_NEGOTIATION_FAILED(msg) \
    do { \
        switch (encryption_negotiation_failed(conn)) \
        { \
            case 0: \
                libpq_append_conn_error(conn, (msg)); \
                goto error_return; \
            case 1: \
                conn->status = CONNECTION_MADE; \
                return PGRES_POLLING_WRITING; \
            case 2: \
                need_new_connection = true; \
                goto keep_going; \
        } \
    } while(0);
 
    /*
     * Decide what to do next, if connection fails.  If there are no options
     * left, return with an error.  The error message has already been written
     * to the connection's error buffer.
     */
#define CONNECTION_FAILED() \
    do { \
        if (connection_failed(conn)) \
        { \
            need_new_connection = true; \
            goto keep_going; \
        } \
        else \
            goto error_return; \
    } while(0);
 
    /* Now try to advance the state machine for this connection */
    switch (conn->status)
    {
        case CONNECTION_NEEDED:
            {
                /*
                 * Try to initiate a connection to one of the addresses
                 * returned by pg_getaddrinfo_all().  conn->whichaddr is the
                 * next one to try.
                 *
                 * The extra level of braces here is historical.  It's not
                 * worth reindenting this whole switch case to remove 'em.
                 */
                {
                    char        host_addr[NI_MAXHOST];
                    int         sock_type;
                    AddrInfo   *addr_cur;
 
                    /*
                     * Advance to next possible host, if we've tried all of
                     * the addresses for the current host.
                     */
                    if (conn->whichaddr == conn->naddr)
                    {
                        conn->try_next_host = true;
                        goto keep_going;
                    }
                    addr_cur = &conn->addr[conn->whichaddr];
 
                    /* Remember current address for possible use later */
                    memcpy(&conn->raddr, &addr_cur->addr, sizeof(SockAddr));
 
#ifdef ENABLE_GSS
 
                    /*
                     * Before establishing the connection, check if it's
                     * doomed to fail because gssencmode='require' but GSSAPI
                     * is not available.
                     */
                    if (conn->gssencmode[0] == 'r')
                    {
                        if (conn->raddr.addr.ss_family == AF_UNIX)
                        {
                            libpq_append_conn_error(conn,
                                                    "GSSAPI encryption required but it is not supported over a local socket");
                            goto error_return;
                        }
                        if (conn->gcred == GSS_C_NO_CREDENTIAL)
                        {
                            if (!pg_GSS_have_cred_cache(&conn->gcred))
                            {
                                libpq_append_conn_error(conn,
                                                        "GSSAPI encryption required but no credential cache");
                                goto error_return;
                            }
                        }
                    }
#endif
 
                    /*
                     * Choose the encryption method to try first.  Do this
                     * before establishing the connection, so that if none of
                     * the modes allowed by the connections options are
                     * available, we can error out before establishing the
                     * connection.
                     */
                    if (!init_allowed_encryption_methods(conn))
                        goto error_return;
 
                    /*
                     * Set connip, too.  Note we purposely ignore strdup
                     * failure; not a big problem if it fails.
                     */
                    if (conn->connip != NULL)
                    {
                        free(conn->connip);
                        conn->connip = NULL;
                    }
                    getHostaddr(conn, host_addr, NI_MAXHOST);
                    if (host_addr[0])
                        conn->connip = strdup(host_addr);
 
                    /* Try to create the socket */
                    sock_type = SOCK_STREAM;
#ifdef SOCK_CLOEXEC
 
                    /*
                     * Atomically mark close-on-exec, if possible on this
                     * platform, so that there isn't a window where a
                     * subprogram executed by another thread inherits the
                     * socket.  See fallback code below.
                     */
                    sock_type |= SOCK_CLOEXEC;
#endif
#ifdef SOCK_NONBLOCK
 
                    /*
                     * We might as well skip a system call for nonblocking
                     * mode too, if we can.
                     */
                    sock_type |= SOCK_NONBLOCK;
#endif
                    conn->sock = socket(addr_cur->family, sock_type, 0);
                    if (conn->sock == PGINVALID_SOCKET)
                    {
                        int         errorno = SOCK_ERRNO;
 
                        /*
                         * Silently ignore socket() failure if we have more
                         * addresses to try; this reduces useless chatter in
                         * cases where the address list includes both IPv4 and
                         * IPv6 but kernel only accepts one family.
                         */
                        if (conn->whichaddr < conn->naddr ||
                            conn->whichhost + 1 < conn->nconnhost)
                        {
                            conn->try_next_addr = true;
                            goto keep_going;
                        }
                        emitHostIdentityInfo(conn, host_addr);
                        libpq_append_conn_error(conn, "could not create socket: %s",
                                                SOCK_STRERROR(errorno, sebuf, sizeof(sebuf)));
                        goto error_return;
                    }
 
                    /*
                     * Once we've identified a target address, all errors
                     * except the preceding socket()-failure case should be
                     * prefixed with host-identity information.  (If the
                     * connection succeeds, the contents of conn->errorMessage
                     * won't matter, so this is harmless.)
                     */
                    emitHostIdentityInfo(conn, host_addr);
 
                    /*
                     * Select socket options: no delay of outgoing data for
                     * TCP sockets, nonblock mode, close-on-exec.  Try the
                     * next address if any of this fails.
                     */
                    if (addr_cur->family != AF_UNIX)
                    {
                        if (!connectNoDelay(conn))
                        {
                            /* error message already created */
                            conn->try_next_addr = true;
                            goto keep_going;
                        }
                    }
#ifndef SOCK_NONBLOCK
                    if (!pg_set_noblock(conn->sock))
                    {
                        libpq_append_conn_error(conn, "could not set socket to nonblocking mode: %s",
                                                SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                        conn->try_next_addr = true;
                        goto keep_going;
                    }
#endif
 
#ifndef SOCK_CLOEXEC
#ifdef F_SETFD
                    if (fcntl(conn->sock, F_SETFD, FD_CLOEXEC) == -1)
                    {
                        libpq_append_conn_error(conn, "could not set socket to close-on-exec mode: %s",
                                                SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                        conn->try_next_addr = true;
                        goto keep_going;
                    }
#endif                          /* F_SETFD */
#endif
 
                    if (addr_cur->family != AF_UNIX)
                    {
#ifndef WIN32
                        int         on = 1;
#endif
                        int         usekeepalives = useKeepalives(conn);
                        int         err = 0;
 
                        if (usekeepalives < 0)
                        {
                            /* error is already reported */
                            err = 1;
                        }
                        else if (usekeepalives == 0)
                        {
                            /* Do nothing */
                        }
#ifndef WIN32
                        else if (setsockopt(conn->sock,
                                            SOL_SOCKET, SO_KEEPALIVE,
                                            (char *) &on, sizeof(on)) < 0)
                        {
                            libpq_append_conn_error(conn, "%s(%s) failed: %s",
                                                    "setsockopt",
                                                    "SO_KEEPALIVE",
                                                    SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                            err = 1;
                        }
                        else if (!setKeepalivesIdle(conn)
                                 || !setKeepalivesInterval(conn)
                                 || !setKeepalivesCount(conn))
                            err = 1;
#else                           /* WIN32 */
#ifdef SIO_KEEPALIVE_VALS
                        else if (!prepKeepalivesWin32(conn))
                            err = 1;
#endif                          /* SIO_KEEPALIVE_VALS */
#endif                          /* WIN32 */
                        else if (!setTCPUserTimeout(conn))
                            err = 1;
 
                        if (err)
                        {
                            conn->try_next_addr = true;
                            goto keep_going;
                        }
                    }
 
                    /*----------
                     * We have three methods of blocking SIGPIPE during
                     * send() calls to this socket:
                     *
                     *  - setsockopt(sock, SO_NOSIGPIPE)
                     *  - send(sock, ..., MSG_NOSIGNAL)
                     *  - setting the signal mask to SIG_IGN during send()
                     *
                     * The third method requires three syscalls per send,
                     * so we prefer either of the first two, but they are
                     * less portable.  The state is tracked in the following
                     * members of PGconn:
                     *
                     * conn->sigpipe_so     - we have set up SO_NOSIGPIPE
                     * conn->sigpipe_flag   - we're specifying MSG_NOSIGNAL
                     *
                     * If we can use SO_NOSIGPIPE, then set sigpipe_so here
                     * and we're done.  Otherwise, set sigpipe_flag so that
                     * we will try MSG_NOSIGNAL on sends.  If we get an error
                     * with MSG_NOSIGNAL, we'll clear that flag and revert to
                     * signal masking.
                     *----------
                     */
                    conn->sigpipe_so = false;
#ifdef MSG_NOSIGNAL
                    conn->sigpipe_flag = true;
#else
                    conn->sigpipe_flag = false;
#endif                          /* MSG_NOSIGNAL */
 
#ifdef SO_NOSIGPIPE
                    optval = 1;
                    if (setsockopt(conn->sock, SOL_SOCKET, SO_NOSIGPIPE,
                                   (char *) &optval, sizeof(optval)) == 0)
                    {
                        conn->sigpipe_so = true;
                        conn->sigpipe_flag = false;
                    }
#endif                          /* SO_NOSIGPIPE */
 
                    /*
                     * Start/make connection.  This should not block, since we
                     * are in nonblock mode.  If it does, well, too bad.
                     */
                    if (connect(conn->sock, (struct sockaddr *) &addr_cur->addr.addr,
                                addr_cur->addr.salen) < 0)
                    {
                        if (SOCK_ERRNO == EINPROGRESS ||
#ifdef WIN32
                            SOCK_ERRNO == EWOULDBLOCK ||
#endif
                            SOCK_ERRNO == EINTR)
                        {
                            /*
                             * This is fine - we're in non-blocking mode, and
                             * the connection is in progress.  Tell caller to
                             * wait for write-ready on socket.
                             */
                            conn->status = CONNECTION_STARTED;
                            return PGRES_POLLING_WRITING;
                        }
                        /* otherwise, trouble */
                    }
                    else
                    {
                        /*
                         * Hm, we're connected already --- seems the "nonblock
                         * connection" wasn't.  Advance the state machine and
                         * go do the next stuff.
                         */
                        conn->status = CONNECTION_STARTED;
                        goto keep_going;
                    }
 
                    /*
                     * This connection failed.  Add the error report to
                     * conn->errorMessage, then try the next address if any.
                     */
                    connectFailureMessage(conn, SOCK_ERRNO);
                    conn->try_next_addr = true;
                    goto keep_going;
                }
            }
 
        case CONNECTION_STARTED:
            {
                socklen_t   optlen = sizeof(optval);
 
                /*
                 * Write ready, since we've made it here, so the connection
                 * has been made ... or has failed.
                 */
 
                /*
                 * Now check (using getsockopt) that there is not an error
                 * state waiting for us on the socket.
                 */
 
                if (getsockopt(conn->sock, SOL_SOCKET, SO_ERROR,
                               (char *) &optval, &optlen) == -1)
                {
                    libpq_append_conn_error(conn, "could not get socket error status: %s",
                                            SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                    goto error_return;
                }
                else if (optval != 0)
                {
                    /*
                     * When using a nonblocking connect, we will typically see
                     * connect failures at this point, so provide a friendly
                     * error message.
                     */
                    connectFailureMessage(conn, optval);
 
                    /*
                     * Try the next address if any, just as in the case where
                     * connect() returned failure immediately.
                     */
                    conn->try_next_addr = true;
                    goto keep_going;
                }
 
                /* Fill in the client address */
                conn->laddr.salen = sizeof(conn->laddr.addr);
                if (getsockname(conn->sock,
                                (struct sockaddr *) &conn->laddr.addr,
                                &conn->laddr.salen) < 0)
                {
                    libpq_append_conn_error(conn, "could not get client address from socket: %s",
                                            SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                    goto error_return;
                }
 
                /*
                 * Implement requirepeer check, if requested and it's a
                 * Unix-domain socket.
                 */
                if (conn->requirepeer && conn->requirepeer[0] &&
                    conn->raddr.addr.ss_family == AF_UNIX)
                {
#ifndef WIN32
                    char       *remote_username;
#endif
                    uid_t       uid;
                    gid_t       gid;
 
                    errno = 0;
                    if (getpeereid(conn->sock, &uid, &gid) != 0)
                    {
                        /*
                         * Provide special error message if getpeereid is a
                         * stub
                         */
                        if (errno == ENOSYS)
                            libpq_append_conn_error(conn, "requirepeer parameter is not supported on this platform");
                        else
                            libpq_append_conn_error(conn, "could not get peer credentials: %s",
                                                    strerror_r(errno, sebuf, sizeof(sebuf)));
                        goto error_return;
                    }
 
#ifndef WIN32
                    remote_username = pg_fe_getusername(uid,
                                                        &conn->errorMessage);
                    if (remote_username == NULL)
                        goto error_return;  /* message already logged */
 
                    if (strcmp(remote_username, conn->requirepeer) != 0)
                    {
                        libpq_append_conn_error(conn, "requirepeer specifies \"%s\", but actual peer user name is \"%s\"",
                                                conn->requirepeer, remote_username);
                        free(remote_username);
                        goto error_return;
                    }
                    free(remote_username);
#else                           /* WIN32 */
                    /* should have failed with ENOSYS above */
                    Assert(false);
#endif                          /* WIN32 */
                }
 
                /*
                 * Make sure we can write before advancing to next step.
                 */
                conn->status = CONNECTION_MADE;
                return PGRES_POLLING_WRITING;
            }
 
        case CONNECTION_MADE:
            {
                char       *startpacket;
                int         packetlen;
 
#ifdef ENABLE_GSS
 
                /*
                 * If GSSAPI encryption is enabled, send a packet to the
                 * server asking for GSSAPI Encryption and proceed with GSSAPI
                 * handshake.  We will come back here after GSSAPI encryption
                 * has been established, with conn->gctx set.
                 */
                if (conn->current_enc_method == ENC_GSSAPI && !conn->gctx)
                {
                    ProtocolVersion pv = pg_hton32(NEGOTIATE_GSS_CODE);
 
                    if (pqPacketSend(conn, 0, &pv, sizeof(pv)) != STATUS_OK)
                    {
                        libpq_append_conn_error(conn, "could not send GSSAPI negotiation packet: %s",
                                                SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                        goto error_return;
                    }
 
                    /* Ok, wait for response */
                    conn->status = CONNECTION_GSS_STARTUP;
                    return PGRES_POLLING_READING;
                }
#endif
 
#ifdef USE_SSL
 
                /*
                 * If SSL is enabled, start the SSL negotiation. We will come
                 * back here after SSL encryption has been established, with
                 * ssl_in_use set.
                 */
                if (conn->current_enc_method == ENC_SSL && !conn->ssl_in_use)
                {
                    /*
                     * If traditional postgres SSL negotiation is used, send
                     * the SSL request.  In direct negotiation, jump straight
                     * into the SSL handshake.
                     */
                    if (conn->sslnegotiation[0] == 'p')
                    {
                        ProtocolVersion pv;
 
                        /*
                         * Send the SSL request packet.
                         *
                         * Theoretically, this could block, but it really
                         * shouldn't since we only got here if the socket is
                         * write-ready.
                         */
                        pv = pg_hton32(NEGOTIATE_SSL_CODE);
                        if (pqPacketSend(conn, 0, &pv, sizeof(pv)) != STATUS_OK)
                        {
                            libpq_append_conn_error(conn, "could not send SSL negotiation packet: %s",
                                                    SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                            goto error_return;
                        }
                        /* Ok, wait for response */
                        conn->status = CONNECTION_SSL_STARTUP;
                        return PGRES_POLLING_READING;
                    }
                    else
                    {
                        Assert(conn->sslnegotiation[0] == 'd');
                        conn->status = CONNECTION_SSL_STARTUP;
                        return PGRES_POLLING_WRITING;
                    }
                }
#endif                          /* USE_SSL */
 
                /*
                 * For cancel requests this is as far as we need to go in the
                 * connection establishment. Now we can actually send our
                 * cancellation request.
                 */
                if (conn->cancelRequest)
                {
                    CancelRequestPacket cancelpacket;
 
                    packetlen = sizeof(cancelpacket);
                    cancelpacket.cancelRequestCode = (MsgType) pg_hton32(CANCEL_REQUEST_CODE);
                    cancelpacket.backendPID = pg_hton32(conn->be_pid);
                    cancelpacket.cancelAuthCode = pg_hton32(conn->be_key);
                    if (pqPacketSend(conn, 0, &cancelpacket, packetlen) != STATUS_OK)
                    {
                        libpq_append_conn_error(conn, "could not send cancel packet: %s",
                                                SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                        goto error_return;
                    }
                    conn->status = CONNECTION_AWAITING_RESPONSE;
                    return PGRES_POLLING_READING;
                }
 
                /*
                 * We have now established encryption, or we are happy to
                 * proceed without.
                 */
 
                /* Build the startup packet. */
                startpacket = pqBuildStartupPacket3(conn, &packetlen,
                                                    EnvironmentOptions);
                if (!startpacket)
                {
                    libpq_append_conn_error(conn, "out of memory");
                    goto error_return;
                }
 
                /*
                 * Send the startup packet.
                 *
                 * Theoretically, this could block, but it really shouldn't
                 * since we only got here if the socket is write-ready.
                 */
                if (pqPacketSend(conn, 0, startpacket, packetlen) != STATUS_OK)
                {
                    libpq_append_conn_error(conn, "could not send startup packet: %s",
                                            SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
                    free(startpacket);
                    goto error_return;
                }
 
                free(startpacket);
 
                conn->status = CONNECTION_AWAITING_RESPONSE;
                return PGRES_POLLING_READING;
            }
 
            /*
             * Handle SSL negotiation: wait for postmaster messages and
             * respond as necessary.
             */
        case CONNECTION_SSL_STARTUP:
            {
#ifdef USE_SSL
                PostgresPollingStatusType pollres;
 
                /*
                 * On first time through with traditional SSL negotiation, get
                 * the postmaster's response to our SSLRequest packet. With
                 * sslnegotiation='direct', go straight to initiating SSL.
                 */
                if (!conn->ssl_in_use && conn->sslnegotiation[0] == 'p')
                {
                    /*
                     * We use pqReadData here since it has the logic to
                     * distinguish no-data-yet from connection closure. Since
                     * conn->ssl isn't set, a plain recv() will occur.
                     */
                    char        SSLok;
                    int         rdresult;
 
                    rdresult = pqReadData(conn);
                    if (rdresult < 0)
                    {
                        /* errorMessage is already filled in */
                        goto error_return;
                    }
                    if (rdresult == 0)
                    {
                        /* caller failed to wait for data */
                        return PGRES_POLLING_READING;
                    }
                    if (pqGetc(&SSLok, conn) < 0)
                    {
                        /* should not happen really */
                        return PGRES_POLLING_READING;
                    }
                    if (SSLok == 'S')
                    {
                        if (conn->Pfdebug)
                            pqTraceOutputCharResponse(conn, "SSLResponse",
                                                      SSLok);
                        /* mark byte consumed */
                        conn->inStart = conn->inCursor;
                    }
                    else if (SSLok == 'N')
                    {
                        if (conn->Pfdebug)
                            pqTraceOutputCharResponse(conn, "SSLResponse",
                                                      SSLok);
                        /* mark byte consumed */
                        conn->inStart = conn->inCursor;
 
                        /*
                         * The connection is still valid, so if it's OK to
                         * continue without SSL, we can proceed using this
                         * connection.  Otherwise return with an error.
                         */
                        ENCRYPTION_NEGOTIATION_FAILED(libpq_gettext("server does not support SSL, but SSL was required"));
                    }
                    else if (SSLok == 'E')
                    {
                        /*
                         * Server failure of some sort, such as failure to
                         * fork a backend process.  Don't bother retrieving
                         * the error message; we should not trust it as the
                         * server has not been authenticated yet.
                         */
                        libpq_append_conn_error(conn, "server sent an error response during SSL exchange");
                        goto error_return;
                    }
                    else
                    {
                        libpq_append_conn_error(conn, "received invalid response to SSL negotiation: %c",
                                                SSLok);
                        goto error_return;
                    }
                }
 
                /*
                 * Begin or continue the SSL negotiation process.
                 */
                pollres = pqsecure_open_client(conn);
                if (pollres == PGRES_POLLING_OK)
                {
                    /*
                     * At this point we should have no data already buffered.
                     * If we do, it was received before we performed the SSL
                     * handshake, so it wasn't encrypted and indeed may have
                     * been injected by a man-in-the-middle.
                     */
                    if (conn->inCursor != conn->inEnd)
                    {
                        libpq_append_conn_error(conn, "received unencrypted data after SSL response");
                        goto error_return;
                    }
 
                    /* SSL handshake done, ready to send startup packet */
                    conn->status = CONNECTION_MADE;
                    return PGRES_POLLING_WRITING;
                }
                if (pollres == PGRES_POLLING_FAILED)
                {
                    /*
                     * SSL handshake failed.  We will retry with a plaintext
                     * connection, if permitted by sslmode.
                     */
                    CONNECTION_FAILED();
                }
                /* Else, return POLLING_READING or POLLING_WRITING status */
                return pollres;
#else                           /* !USE_SSL */
                /* can't get here */
                goto error_return;
#endif                          /* USE_SSL */
            }
 
        case CONNECTION_GSS_STARTUP:
            {
#ifdef ENABLE_GSS
                PostgresPollingStatusType pollres;
 
                /*
                 * If we haven't yet, get the postmaster's response to our
                 * negotiation packet
                 */
                if (!conn->gctx)
                {
                    char        gss_ok;
                    int         rdresult = pqReadData(conn);
 
                    if (rdresult < 0)
                        /* pqReadData fills in error message */
                        goto error_return;
                    else if (rdresult == 0)
                        /* caller failed to wait for data */
                        return PGRES_POLLING_READING;
                    if (pqGetc(&gss_ok, conn) < 0)
                        /* shouldn't happen... */
                        return PGRES_POLLING_READING;
 
                    if (gss_ok == 'E')
                    {
                        /*
                         * Server failure of some sort, possibly protocol
                         * version support failure.  Don't bother retrieving
                         * the error message; we should not trust it anyway as
                         * the server has not authenticated yet.
                         *
                         * Note that unlike on an error response to
                         * SSLRequest, we allow falling back to SSL or
                         * plaintext connection here.  GSS support was
                         * introduced in PostgreSQL version 12, so an error
                         * response might mean that we are connecting to a
                         * pre-v12 server.
                         */
                        libpq_append_conn_error(conn, "server sent an error response during GSS encryption exchange");
                        CONNECTION_FAILED();
                    }
 
                    /* mark byte consumed */
                    conn->inStart = conn->inCursor;
 
                    if (gss_ok == 'N')
                    {
                        if (conn->Pfdebug)
                            pqTraceOutputCharResponse(conn, "GSSENCResponse",
                                                      gss_ok);
 
                        /*
                         * The connection is still valid, so if it's OK to
                         * continue without GSS, we can proceed using this
                         * connection.  Otherwise return with an error.
                         */
                        ENCRYPTION_NEGOTIATION_FAILED(libpq_gettext("server doesn't support GSSAPI encryption, but it was required"));
                    }
                    else if (gss_ok != 'G')
                    {
                        libpq_append_conn_error(conn, "received invalid response to GSSAPI negotiation: %c",
                                                gss_ok);
                        goto error_return;
                    }
 
                    if (conn->Pfdebug)
                        pqTraceOutputCharResponse(conn, "GSSENCResponse",
                                                  gss_ok);
                }
 
                /* Begin or continue GSSAPI negotiation */
                pollres = pqsecure_open_gss(conn);
                if (pollres == PGRES_POLLING_OK)
                {
                    /*
                     * At this point we should have no data already buffered.
                     * If we do, it was received before we performed the GSS
                     * handshake, so it wasn't encrypted and indeed may have
                     * been injected by a man-in-the-middle.
                     */
                    if (conn->inCursor != conn->inEnd)
                    {
                        libpq_append_conn_error(conn, "received unencrypted data after GSSAPI encryption response");
                        goto error_return;
                    }
 
                    /* All set for startup packet */
                    conn->status = CONNECTION_MADE;
                    return PGRES_POLLING_WRITING;
                }
                else if (pollres == PGRES_POLLING_FAILED)
                {
                    /*
                     * GSS handshake failed.  We will retry with an SSL or
                     * plaintext connection, if permitted by the options.
                     */
                    CONNECTION_FAILED();
                }
                /* Else, return POLLING_READING or POLLING_WRITING status */
                return pollres;
#else                           /* !ENABLE_GSS */
                /* unreachable */
                goto error_return;
#endif                          /* ENABLE_GSS */
            }
 
            /*
             * Handle authentication exchange: wait for postmaster messages
             * and respond as necessary.
             */
        case CONNECTION_AWAITING_RESPONSE:
            {
                char        beresp;
                int         msgLength;
                int         avail;
                AuthRequest areq;
                int         res;
 
                /*
                 * Scan the message from current point (note that if we find
                 * the message is incomplete, we will return without advancing
                 * inStart, and resume here next time).
                 */
                conn->inCursor = conn->inStart;
 
                /* Read type byte */
                if (pqGetc(&beresp, conn))
                {
                    /* We'll come back when there is more data */
                    return PGRES_POLLING_READING;
                }
 
                /*
                 * Validate message type: we expect only an authentication
                 * request, NegotiateProtocolVersion, or an error here.
                 * Anything else probably means it's not Postgres on the other
                 * end at all.
                 */
                if (beresp != PqMsg_AuthenticationRequest &&
                    beresp != PqMsg_ErrorResponse &&
                    beresp != PqMsg_NegotiateProtocolVersion)
                {
                    libpq_append_conn_error(conn, "expected authentication request from server, but received %c",
                                            beresp);
                    goto error_return;
                }
 
                /* Read message length word */
                if (pqGetInt(&msgLength, 4, conn))
                {
                    /* We'll come back when there is more data */
                    return PGRES_POLLING_READING;
                }
 
                /*
                 * Try to validate message length before using it.
                 *
                 * Authentication requests can't be very large, although GSS
                 * auth requests may not be that small.  Same for
                 * NegotiateProtocolVersion.
                 *
                 * Errors can be a little larger, but not huge.  If we see a
                 * large apparent length in an error, it means we're really
                 * talking to a pre-3.0-protocol server; cope.  (Before
                 * version 14, the server also used the old protocol for
                 * errors that happened before processing the startup packet.)
                 */
                if (beresp == PqMsg_AuthenticationRequest &&
                    (msgLength < 8 || msgLength > 2000))
                {
                    libpq_append_conn_error(conn, "received invalid authentication request");
                    goto error_return;
                }
                if (beresp == PqMsg_NegotiateProtocolVersion &&
                    (msgLength < 8 || msgLength > 2000))
                {
                    libpq_append_conn_error(conn, "received invalid protocol negotiation message");
                    goto error_return;
                }
 
#define MAX_ERRLEN 30000
                if (beresp == PqMsg_ErrorResponse &&
                    (msgLength < 8 || msgLength > MAX_ERRLEN))
                {
                    /* Handle error from a pre-3.0 server */
                    conn->inCursor = conn->inStart + 1; /* reread data */
                    if (pqGets_append(&conn->errorMessage, conn))
                    {
                        /*
                         * We may not have authenticated the server yet, so
                         * don't let the buffer grow forever.
                         */
                        avail = conn->inEnd - conn->inCursor;
                        if (avail > MAX_ERRLEN)
                        {
                            libpq_append_conn_error(conn, "received invalid error message");
                            goto error_return;
                        }
 
                        /* We'll come back when there is more data */
                        return PGRES_POLLING_READING;
                    }
                    /* OK, we read the message; mark data consumed */
                    pqParseDone(conn, conn->inCursor);
 
                    /*
                     * Before 7.2, the postmaster didn't always end its
                     * messages with a newline, so add one if needed to
                     * conform to libpq conventions.
                     */
                    if (conn->errorMessage.len == 0 ||
                        conn->errorMessage.data[conn->errorMessage.len - 1] != '\n')
                    {
                        appendPQExpBufferChar(&conn->errorMessage, '\n');
                    }
 
                    goto error_return;
                }
#undef MAX_ERRLEN
 
                /*
                 * Can't process if message body isn't all here yet.
                 *
                 * After this check passes, any further EOF during parsing
                 * implies that the server sent a bad/truncated message.
                 * Reading more bytes won't help in that case, so don't return
                 * PGRES_POLLING_READING after this point.
                 */
                msgLength -= 4;
                avail = conn->inEnd - conn->inCursor;
                if (avail < msgLength)
                {
                    /*
                     * Before returning, try to enlarge the input buffer if
                     * needed to hold the whole message; see notes in
                     * pqParseInput3.
                     */
                    if (pqCheckInBufferSpace(conn->inCursor + (size_t) msgLength,
                                             conn))
                        goto error_return;
                    /* We'll come back when there is more data */
                    return PGRES_POLLING_READING;
                }
 
                /* Handle errors. */
                if (beresp == PqMsg_ErrorResponse)
                {
                    if (pqGetErrorNotice3(conn, true))
                    {
                        libpq_append_conn_error(conn, "received invalid error message");
                        goto error_return;
                    }
                    /* OK, we read the message; mark data consumed */
                    pqParseDone(conn, conn->inCursor);
 
                    /*
                     * If error is "cannot connect now", try the next host if
                     * any (but we don't want to consider additional addresses
                     * for this host, nor is there much point in changing SSL
                     * or GSS mode).  This is helpful when dealing with
                     * standby servers that might not be in hot-standby state.
                     */
                    if (strcmp(conn->last_sqlstate,
                               ERRCODE_CANNOT_CONNECT_NOW) == 0)
                    {
                        conn->try_next_host = true;
                        goto keep_going;
                    }
 
                    /* Check to see if we should mention pgpassfile */
                    pgpassfileWarning(conn);
 
                    CONNECTION_FAILED();
                }
                else if (beresp == PqMsg_NegotiateProtocolVersion)
                {
                    if (pqGetNegotiateProtocolVersion3(conn))
                    {
                        libpq_append_conn_error(conn, "received invalid protocol negotiation message");
                        goto error_return;
                    }
                    /* OK, we read the message; mark data consumed */
                    pqParseDone(conn, conn->inCursor);
                    goto error_return;
                }
 
                /* It is an authentication request. */
                conn->auth_req_received = true;
 
                /* Get the type of request. */
                if (pqGetInt((int *) &areq, 4, conn))
                {
                    /* can't happen because we checked the length already */
                    libpq_append_conn_error(conn, "received invalid authentication request");
                    goto error_return;
                }
                msgLength -= 4;
 
                /*
                 * Process the rest of the authentication request message, and
                 * respond to it if necessary.
                 *
                 * Note that conn->pghost must be non-NULL if we are going to
                 * avoid the Kerberos code doing a hostname look-up.
                 */
                res = pg_fe_sendauth(areq, msgLength, conn);
 
                /*
                 * OK, we have processed the message; mark data consumed.  We
                 * don't call pqParseDone here because we already traced this
                 * message inside pg_fe_sendauth.
                 */
                conn->inStart = conn->inCursor;
 
                if (res != STATUS_OK)
                    goto error_return;
 
                /*
                 * Just make sure that any data sent by pg_fe_sendauth is
                 * flushed out.  Although this theoretically could block, it
                 * really shouldn't since we don't send large auth responses.
                 */
                if (pqFlush(conn))
                    goto error_return;
 
                if (areq == AUTH_REQ_OK)
                {
                    /* We are done with authentication exchange */
                    conn->status = CONNECTION_AUTH_OK;
 
                    /*
                     * Set asyncStatus so that PQgetResult will think that
                     * what comes back next is the result of a query.  See
                     * below.
                     */
                    conn->asyncStatus = PGASYNC_BUSY;
                }
 
                /* Look to see if we have more data yet. */
                goto keep_going;
            }
 
        case CONNECTION_AUTH_OK:
            {
                /*
                 * Now we expect to hear from the backend. A ReadyForQuery
                 * message indicates that startup is successful, but we might
                 * also get an Error message indicating failure. (Notice
                 * messages indicating nonfatal warnings are also allowed by
                 * the protocol, as are ParameterStatus and BackendKeyData
                 * messages.) Easiest way to handle this is to let
                 * PQgetResult() read the messages. We just have to fake it
                 * out about the state of the connection, by setting
                 * asyncStatus = PGASYNC_BUSY (done above).
                 */
 
                if (PQisBusy(conn))
                    return PGRES_POLLING_READING;
 
                res = PQgetResult(conn);
 
                /*
                 * NULL return indicating we have gone to IDLE state is
                 * expected
                 */
                if (res)
                {
                    if (res->resultStatus != PGRES_FATAL_ERROR)
                        libpq_append_conn_error(conn, "unexpected message from server during startup");
                    else if (conn->send_appname &&
                             (conn->appname || conn->fbappname))
                    {
                        /*
                         * If we tried to send application_name, check to see
                         * if the error is about that --- pre-9.0 servers will
                         * reject it at this stage of the process.  If so,
                         * close the connection and retry without sending
                         * application_name.  We could possibly get a false
                         * SQLSTATE match here and retry uselessly, but there
                         * seems no great harm in that; we'll just get the
                         * same error again if it's unrelated.
                         */
                        const char *sqlstate;
 
                        sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE);
                        if (sqlstate &&
                            strcmp(sqlstate, ERRCODE_APPNAME_UNKNOWN) == 0)
                        {
                            PQclear(res);
                            conn->send_appname = false;
                            need_new_connection = true;
                            goto keep_going;
                        }
                    }
 
                    /*
                     * if the resultStatus is FATAL, then conn->errorMessage
                     * already has a copy of the error; needn't copy it back.
                     * But add a newline if it's not there already, since
                     * postmaster error messages may not have one.
                     */
                    if (conn->errorMessage.len <= 0 ||
                        conn->errorMessage.data[conn->errorMessage.len - 1] != '\n')
                        appendPQExpBufferChar(&conn->errorMessage, '\n');
                    PQclear(res);
                    goto error_return;
                }
 
                /* Almost there now ... */
                conn->status = CONNECTION_CHECK_TARGET;
                goto keep_going;
            }
 
        case CONNECTION_CHECK_TARGET:
            {
                /*
                 * If a read-write, read-only, primary, or standby connection
                 * is required, see if we have one.
                 */
                if (conn->target_server_type == SERVER_TYPE_READ_WRITE ||
                    conn->target_server_type == SERVER_TYPE_READ_ONLY)
                {
                    bool        read_only_server;
 
                    /*
                     * If the server didn't report
                     * "default_transaction_read_only" or "in_hot_standby" at
                     * startup, we must determine its state by sending the
                     * query "SHOW transaction_read_only".  This GUC exists in
                     * all server versions that support 3.0 protocol.
                     */
                    if (conn->default_transaction_read_only == PG_BOOL_UNKNOWN ||
                        conn->in_hot_standby == PG_BOOL_UNKNOWN)
                    {
                        /*
                         * We use PQsendQueryContinue so that
                         * conn->errorMessage does not get cleared.  We need
                         * to preserve any error messages related to previous
                         * hosts we have tried and failed to connect to.
                         */
                        conn->status = CONNECTION_OK;
                        if (!PQsendQueryContinue(conn,
                                                 "SHOW transaction_read_only"))
                            goto error_return;
                        /* We'll return to this state when we have the answer */
                        conn->status = CONNECTION_CHECK_WRITABLE;
                        return PGRES_POLLING_READING;
                    }
 
                    /* OK, we can make the test */
                    read_only_server =
                        (conn->default_transaction_read_only == PG_BOOL_YES ||
                         conn->in_hot_standby == PG_BOOL_YES);
 
                    if ((conn->target_server_type == SERVER_TYPE_READ_WRITE) ?
                        read_only_server : !read_only_server)
                    {
                        /* Wrong server state, reject and try the next host */
                        if (conn->target_server_type == SERVER_TYPE_READ_WRITE)
                            libpq_append_conn_error(conn, "session is read-only");
                        else
                            libpq_append_conn_error(conn, "session is not read-only");
 
                        /* Close connection politely. */
                        conn->status = CONNECTION_OK;
                        sendTerminateConn(conn);
 
                        /*
                         * Try next host if any, but we don't want to consider
                         * additional addresses for this host.
                         */
                        conn->try_next_host = true;
                        goto keep_going;
                    }
                }
                else if (conn->target_server_type == SERVER_TYPE_PRIMARY ||
                         conn->target_server_type == SERVER_TYPE_STANDBY ||
                         conn->target_server_type == SERVER_TYPE_PREFER_STANDBY)
                {
                    /*
                     * If the server didn't report "in_hot_standby" at
                     * startup, we must determine its state by sending the
                     * query "SELECT pg_catalog.pg_is_in_recovery()".  Servers
                     * before 9.0 don't have that function, but by the same
                     * token they don't have any standby mode, so we may just
                     * assume the result.
                     */
                    if (conn->sversion < 90000)
                        conn->in_hot_standby = PG_BOOL_NO;
 
                    if (conn->in_hot_standby == PG_BOOL_UNKNOWN)
                    {
                        /*
                         * We use PQsendQueryContinue so that
                         * conn->errorMessage does not get cleared.  We need
                         * to preserve any error messages related to previous
                         * hosts we have tried and failed to connect to.
                         */
                        conn->status = CONNECTION_OK;
                        if (!PQsendQueryContinue(conn,
                                                 "SELECT pg_catalog.pg_is_in_recovery()"</