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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) 2016-2020, 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  */
81 void
83 {
84  context->type = type;
85 
86  switch (type)
87  {
88  case CHECKSUM_TYPE_NONE:
89  /* do nothing */
90  break;
93  break;
96  break;
99  break;
102  break;
105  break;
106  }
107 }
108 
109 /*
110  * Update a checksum context with new data.
111  */
112 void
114  size_t len)
115 {
116  switch (context->type)
117  {
118  case CHECKSUM_TYPE_NONE:
119  /* do nothing */
120  break;
122  COMP_CRC32C(context->raw_context.c_crc32c, input, len);
123  break;
125  pg_sha224_update(&context->raw_context.c_sha224, input, len);
126  break;
128  pg_sha256_update(&context->raw_context.c_sha256, input, len);
129  break;
131  pg_sha384_update(&context->raw_context.c_sha384, input, len);
132  break;
134  pg_sha512_update(&context->raw_context.c_sha512, input, len);
135  break;
136  }
137 }
138 
139 /*
140  * Finalize a checksum computation and write the result to an output buffer.
141  *
142  * The caller must ensure that the buffer is at least PG_CHECKSUM_MAX_LENGTH
143  * bytes in length. The return value is the number of bytes actually written.
144  */
145 int
147 {
148  int retval = 0;
149 
151  "CRC-32C digest too big for PG_CHECKSUM_MAX_LENGTH");
153  "SHA224 digest too for PG_CHECKSUM_MAX_LENGTH");
155  "SHA256 digest too for PG_CHECKSUM_MAX_LENGTH");
157  "SHA384 digest too for PG_CHECKSUM_MAX_LENGTH");
159  "SHA512 digest too for PG_CHECKSUM_MAX_LENGTH");
160 
161  switch (context->type)
162  {
163  case CHECKSUM_TYPE_NONE:
164  break;
166  FIN_CRC32C(context->raw_context.c_crc32c);
167  retval = sizeof(pg_crc32c);
168  memcpy(output, &context->raw_context.c_crc32c, retval);
169  break;
171  pg_sha224_final(&context->raw_context.c_sha224, output);
172  retval = PG_SHA224_DIGEST_LENGTH;
173  break;
175  pg_sha256_final(&context->raw_context.c_sha256, output);
176  retval = PG_SHA256_DIGEST_LENGTH;
177  break;
179  pg_sha384_final(&context->raw_context.c_sha384, output);
180  retval = PG_SHA384_DIGEST_LENGTH;
181  break;
183  pg_sha512_final(&context->raw_context.c_sha512, output);
184  retval = PG_SHA512_DIGEST_LENGTH;
185  break;
186  }
187 
188  Assert(retval <= PG_CHECKSUM_MAX_LENGTH);
189  return retval;
190 }
#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:62
unsigned char uint8
Definition: c.h:372
void pg_checksum_update(pg_checksum_context *context, const uint8 *input, size_t len)
bool pg_checksum_parse_type(char *name, pg_checksum_type *type)
#define PG_SHA512_DIGEST_LENGTH
Definition: sha2.h:68
int pg_strcasecmp(const char *s1, const char *s2)
Definition: pgstrcasecmp.c:36
#define PG_CHECKSUM_MAX_LENGTH
void pg_sha256_init(pg_sha256_ctx *context)
Definition: sha2.c:268
void pg_sha384_update(pg_sha384_ctx *context, const uint8 *data, size_t len)
Definition: sha2.c:933
#define StaticAssertStmt(condition, errmessage)
Definition: c.h:859
void pg_checksum_init(pg_checksum_context *context, pg_checksum_type type)
void pg_sha512_final(pg_sha512_ctx *context, uint8 *digest)
Definition: sha2.c:894
void pg_sha224_final(pg_sha224_ctx *context, uint8 *digest)
Definition: sha2.c:983
void pg_sha512_update(pg_sha512_ctx *context, const uint8 *data, size_t len)
Definition: sha2.c:791
pg_checksum_type
void pg_sha224_init(pg_sha224_ctx *context)
Definition: sha2.c:967
void pg_sha256_update(pg_sha256_ctx *context, const uint8 *data, size_t len)
Definition: sha2.c:465
int pg_checksum_final(pg_checksum_context *context, uint8 *output)
void pg_sha224_update(pg_sha224_ctx *context, const uint8 *data, size_t len)
Definition: sha2.c:977
void pg_sha384_final(pg_sha384_ctx *context, uint8 *digest)
Definition: sha2.c:939
#define Assert(condition)
Definition: c.h:745
void pg_sha384_init(pg_sha384_ctx *context)
Definition: sha2.c:923
const char * name
Definition: encode.c:561
void pg_sha512_init(pg_sha512_ctx *context)
Definition: sha2.c:594
void pg_sha256_final(pg_sha256_ctx *context, uint8 *digest)
Definition: sha2.c:566
#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:59
#define PG_SHA384_DIGEST_LENGTH
Definition: sha2.h:65