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checksum_helper.c
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1 /*-------------------------------------------------------------------------
2  *
3  * checksum_helper.c
4  * Compute a checksum of any of various types using common routines
5  *
6  * Portions Copyright (c) 2016-2021, PostgreSQL Global Development Group
7  *
8  * IDENTIFICATION
9  * src/common/checksum_helper.c
10  *
11  *-------------------------------------------------------------------------
12  */
13 
14 #ifndef FRONTEND
15 #include "postgres.h"
16 #else
17 #include "postgres_fe.h"
18 #endif
19 
20 #include "common/checksum_helper.h"
21 
22 /*
23  * If 'name' is a recognized checksum type, set *type to the corresponding
24  * constant and return true. Otherwise, set *type to CHECKSUM_TYPE_NONE and
25  * return false.
26  */
27 bool
29 {
31  bool result = true;
32 
33  if (pg_strcasecmp(name, "none") == 0)
34  result_type = CHECKSUM_TYPE_NONE;
35  else if (pg_strcasecmp(name, "crc32c") == 0)
36  result_type = CHECKSUM_TYPE_CRC32C;
37  else if (pg_strcasecmp(name, "sha224") == 0)
38  result_type = CHECKSUM_TYPE_SHA224;
39  else if (pg_strcasecmp(name, "sha256") == 0)
40  result_type = CHECKSUM_TYPE_SHA256;
41  else if (pg_strcasecmp(name, "sha384") == 0)
42  result_type = CHECKSUM_TYPE_SHA384;
43  else if (pg_strcasecmp(name, "sha512") == 0)
44  result_type = CHECKSUM_TYPE_SHA512;
45  else
46  result = false;
47 
48  *type = result_type;
49  return result;
50 }
51 
52 /*
53  * Get the canonical human-readable name corresponding to a checksum type.
54  */
55 char *
57 {
58  switch (type)
59  {
60  case CHECKSUM_TYPE_NONE:
61  return "NONE";
63  return "CRC32C";
65  return "SHA224";
67  return "SHA256";
69  return "SHA384";
71  return "SHA512";
72  }
73 
74  Assert(false);
75  return "???";
76 }
77 
78 /*
79  * Initialize a checksum context for checksums of the given type.
80  * Returns 0 for a success, -1 for a failure.
81  */
82 int
84 {
85  context->type = type;
86 
87  switch (type)
88  {
89  case CHECKSUM_TYPE_NONE:
90  /* do nothing */
91  break;
94  break;
97  if (context->raw_context.c_sha2 == NULL)
98  return -1;
99  if (pg_cryptohash_init(context->raw_context.c_sha2) < 0)
100  {
102  return -1;
103  }
104  break;
107  if (context->raw_context.c_sha2 == NULL)
108  return -1;
109  if (pg_cryptohash_init(context->raw_context.c_sha2) < 0)
110  {
112  return -1;
113  }
114  break;
117  if (context->raw_context.c_sha2 == NULL)
118  return -1;
119  if (pg_cryptohash_init(context->raw_context.c_sha2) < 0)
120  {
122  return -1;
123  }
124  break;
127  if (context->raw_context.c_sha2 == NULL)
128  return -1;
129  if (pg_cryptohash_init(context->raw_context.c_sha2) < 0)
130  {
132  return -1;
133  }
134  break;
135  }
136 
137  return 0;
138 }
139 
140 /*
141  * Update a checksum context with new data.
142  * Returns 0 for a success, -1 for a failure.
143  */
144 int
146  size_t len)
147 {
148  switch (context->type)
149  {
150  case CHECKSUM_TYPE_NONE:
151  /* do nothing */
152  break;
154  COMP_CRC32C(context->raw_context.c_crc32c, input, len);
155  break;
160  if (pg_cryptohash_update(context->raw_context.c_sha2, input, len) < 0)
161  return -1;
162  break;
163  }
164 
165  return 0;
166 }
167 
168 /*
169  * Finalize a checksum computation and write the result to an output buffer.
170  *
171  * The caller must ensure that the buffer is at least PG_CHECKSUM_MAX_LENGTH
172  * bytes in length. The return value is the number of bytes actually written,
173  * or -1 for a failure.
174  */
175 int
177 {
178  int retval = 0;
179 
181  "CRC-32C digest too big for PG_CHECKSUM_MAX_LENGTH");
183  "SHA224 digest too big for PG_CHECKSUM_MAX_LENGTH");
185  "SHA256 digest too big for PG_CHECKSUM_MAX_LENGTH");
187  "SHA384 digest too big for PG_CHECKSUM_MAX_LENGTH");
189  "SHA512 digest too big for PG_CHECKSUM_MAX_LENGTH");
190 
191  switch (context->type)
192  {
193  case CHECKSUM_TYPE_NONE:
194  break;
196  FIN_CRC32C(context->raw_context.c_crc32c);
197  retval = sizeof(pg_crc32c);
198  memcpy(output, &context->raw_context.c_crc32c, retval);
199  break;
201  retval = PG_SHA224_DIGEST_LENGTH;
203  output, retval) < 0)
204  return -1;
206  break;
208  retval = PG_SHA256_DIGEST_LENGTH;
210  output, retval) < 0)
211  return -1;
213  break;
215  retval = PG_SHA384_DIGEST_LENGTH;
217  output, retval) < 0)
218  return -1;
220  break;
222  retval = PG_SHA512_DIGEST_LENGTH;
224  output, retval) < 0)
225  return -1;
227  break;
228  }
229 
230  Assert(retval <= PG_CHECKSUM_MAX_LENGTH);
231  return retval;
232 }
int pg_cryptohash_final(pg_cryptohash_ctx *ctx, uint8 *dest, size_t len)
Definition: cryptohash.c:168
#define INIT_CRC32C(crc)
Definition: pg_crc32c.h:41
char * pg_checksum_type_name(pg_checksum_type type)
static void output(uint64 loop_count)
uint32 pg_crc32c
Definition: pg_crc32c.h:38
pg_checksum_raw_context raw_context
#define PG_SHA256_DIGEST_LENGTH
Definition: sha2.h:22
unsigned char uint8
Definition: c.h:439
bool pg_checksum_parse_type(char *name, pg_checksum_type *type)
#define PG_SHA512_DIGEST_LENGTH
Definition: sha2.h:26
int pg_strcasecmp(const char *s1, const char *s2)
Definition: pgstrcasecmp.c:36
#define PG_CHECKSUM_MAX_LENGTH
#define StaticAssertStmt(condition, errmessage)
Definition: c.h:918
pg_checksum_type
int pg_checksum_final(pg_checksum_context *context, uint8 *output)
pg_cryptohash_ctx * c_sha2
int pg_checksum_init(pg_checksum_context *context, pg_checksum_type type)
pg_cryptohash_ctx * pg_cryptohash_create(pg_cryptohash_type type)
Definition: cryptohash.c:66
#define Assert(condition)
Definition: c.h:804
int pg_cryptohash_init(pg_cryptohash_ctx *ctx)
Definition: cryptohash.c:92
int pg_checksum_update(pg_checksum_context *context, const uint8 *input, size_t len)
const char * name
Definition: encode.c:515
int pg_cryptohash_update(pg_cryptohash_ctx *ctx, const uint8 *data, size_t len)
Definition: cryptohash.c:130
void pg_cryptohash_free(pg_cryptohash_ctx *ctx)
Definition: cryptohash.c:216
#define COMP_CRC32C(crc, data, len)
Definition: pg_crc32c.h:89
pg_checksum_type type
#define FIN_CRC32C(crc)
Definition: pg_crc32c.h:94
#define PG_SHA224_DIGEST_LENGTH
Definition: sha2.h:20
#define PG_SHA384_DIGEST_LENGTH
Definition: sha2.h:24