PostgreSQL Source Code  git master
passwordcheck.c File Reference
#include "postgres.h"
#include <ctype.h>
#include "commands/user.h"
#include "fmgr.h"
#include "libpq/crypt.h"
Include dependency graph for passwordcheck.c:

Go to the source code of this file.

Macros

#define MIN_PWD_LENGTH   8
 

Functions

void _PG_init (void)
 
void _PG_fini (void)
 
static void check_password (const char *username, const char *shadow_pass, PasswordType password_type, Datum validuntil_time, bool validuntil_null)
 

Variables

 PG_MODULE_MAGIC
 
static check_password_hook_type prev_check_password_hook = NULL
 

Macro Definition Documentation

◆ MIN_PWD_LENGTH

#define MIN_PWD_LENGTH   8

Definition at line 33 of file passwordcheck.c.

Referenced by check_password().

Function Documentation

◆ _PG_fini()

void _PG_fini ( void  )

Definition at line 157 of file passwordcheck.c.

References check_password_hook, and prev_check_password_hook.

158 {
159  /* uninstall hook */
161 }
static check_password_hook_type prev_check_password_hook
Definition: passwordcheck.c:30
check_password_hook_type check_password_hook
Definition: user.c:49

◆ _PG_init()

void _PG_init ( void  )

Definition at line 146 of file passwordcheck.c.

References check_password(), check_password_hook, and prev_check_password_hook.

147 {
148  /* activate password checks when the module is loaded */
151 }
static check_password_hook_type prev_check_password_hook
Definition: passwordcheck.c:30
static void check_password(const char *username, const char *shadow_pass, PasswordType password_type, Datum validuntil_time, bool validuntil_null)
Definition: passwordcheck.c:56
check_password_hook_type check_password_hook
Definition: user.c:49

◆ check_password()

static void check_password ( const char *  username,
const char *  shadow_pass,
PasswordType  password_type,
Datum  validuntil_time,
bool  validuntil_null 
)
static

Definition at line 56 of file passwordcheck.c.

References ereport, errcode(), errdetail_log(), errmsg(), ERROR, i, MIN_PWD_LENGTH, password, PASSWORD_TYPE_PLAINTEXT, plain_crypt_verify(), prev_check_password_hook, and STATUS_OK.

Referenced by _PG_init().

61 {
64  password_type, validuntil_time,
65  validuntil_null);
66 
67  if (password_type != PASSWORD_TYPE_PLAINTEXT)
68  {
69  /*
70  * Unfortunately we cannot perform exhaustive checks on encrypted
71  * passwords - we are restricted to guessing. (Alternatively, we could
72  * insist on the password being presented non-encrypted, but that has
73  * its own security disadvantages.)
74  *
75  * We only check for username = password.
76  */
77  char *logdetail;
78 
79  if (plain_crypt_verify(username, shadow_pass, username, &logdetail) == STATUS_OK)
80  ereport(ERROR,
81  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
82  errmsg("password must not equal user name")));
83  }
84  else
85  {
86  /*
87  * For unencrypted passwords we can perform better checks
88  */
89  const char *password = shadow_pass;
90  int pwdlen = strlen(password);
91  int i;
92  bool pwd_has_letter,
93  pwd_has_nonletter;
94 #ifdef USE_CRACKLIB
95  const char *reason;
96 #endif
97 
98  /* enforce minimum length */
99  if (pwdlen < MIN_PWD_LENGTH)
100  ereport(ERROR,
101  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
102  errmsg("password is too short")));
103 
104  /* check if the password contains the username */
105  if (strstr(password, username))
106  ereport(ERROR,
107  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
108  errmsg("password must not contain user name")));
109 
110  /* check if the password contains both letters and non-letters */
111  pwd_has_letter = false;
112  pwd_has_nonletter = false;
113  for (i = 0; i < pwdlen; i++)
114  {
115  /*
116  * isalpha() does not work for multibyte encodings but let's
117  * consider non-ASCII characters non-letters
118  */
119  if (isalpha((unsigned char) password[i]))
120  pwd_has_letter = true;
121  else
122  pwd_has_nonletter = true;
123  }
124  if (!pwd_has_letter || !pwd_has_nonletter)
125  ereport(ERROR,
126  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
127  errmsg("password must contain both letters and nonletters")));
128 
129 #ifdef USE_CRACKLIB
130  /* call cracklib to check password */
131  if ((reason = FascistCheck(password, CRACKLIB_DICTPATH)))
132  ereport(ERROR,
133  (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
134  errmsg("password is easily cracked"),
135  errdetail_log("cracklib diagnostic: %s", reason)));
136 #endif
137  }
138 
139  /* all checks passed, password is ok */
140 }
static check_password_hook_type prev_check_password_hook
Definition: passwordcheck.c:30
int plain_crypt_verify(const char *role, const char *shadow_pass, const char *client_pass, char **logdetail)
Definition: crypt.c:222
int errcode(int sqlerrcode)
Definition: elog.c:691
#define ERROR
Definition: elog.h:43
int errdetail_log(const char *fmt,...)
Definition: elog.c:1083
static char * password
Definition: streamutil.c:53
#define STATUS_OK
Definition: c.h:1166
static char * username
Definition: initdb.c:134
#define ereport(elevel,...)
Definition: elog.h:155
int errmsg(const char *fmt,...)
Definition: elog.c:902
int i
#define MIN_PWD_LENGTH
Definition: passwordcheck.c:33

Variable Documentation

◆ PG_MODULE_MAGIC

PG_MODULE_MAGIC

Definition at line 27 of file passwordcheck.c.

◆ prev_check_password_hook

check_password_hook_type prev_check_password_hook = NULL
static

Definition at line 30 of file passwordcheck.c.

Referenced by _PG_fini(), _PG_init(), and check_password().