MySQL 8.0.29
Source Code Documentation
sql_digest.h
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1/* Copyright (c) 2008, 2021, Oracle and/or its affiliates.
2
3 This program is free software; you can redistribute it and/or modify
4 it under the terms of the GNU General Public License, version 2.0,
5 as published by the Free Software Foundation.
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7 This program is also distributed with certain software (including
8 but not limited to OpenSSL) that is licensed under separate terms,
9 as designated in a particular file or component or in included license
10 documentation. The authors of MySQL hereby grant you an additional
11 permission to link the program and your derivative works with the
12 separately licensed software that they have included with MySQL.
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14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License, version 2.0, for more details.
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19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
22
23#ifndef SQL_DIGEST_H
24#define SQL_DIGEST_H
25
26#include <string.h>
27#include <sys/types.h>
28
29#include "my_inttypes.h" // IWYU pragma: keep
30
31class String;
32
33#define MAX_DIGEST_STORAGE_SIZE (1024 * 1024)
34
35/**
36 Write SHA-256 hash value in a string to be used
37 as DIGEST for the statement.
38*/
39#define DIGEST_HASH_TO_STRING(_hash, _str) \
40 sprintf(_str, \
41 "%02x%02x%02x%02x%02x%02x%02x%02x" \
42 "%02x%02x%02x%02x%02x%02x%02x%02x" \
43 "%02x%02x%02x%02x%02x%02x%02x%02x" \
44 "%02x%02x%02x%02x%02x%02x%02x%02x", \
45 _hash[0], _hash[1], _hash[2], _hash[3], _hash[4], _hash[5], \
46 _hash[6], _hash[7], _hash[8], _hash[9], _hash[10], _hash[11], \
47 _hash[12], _hash[13], _hash[14], _hash[15], _hash[16], _hash[17], \
48 _hash[18], _hash[19], _hash[20], _hash[21], _hash[22], _hash[23], \
49 _hash[24], _hash[25], _hash[26], _hash[27], _hash[28], _hash[29], \
50 _hash[30], _hash[31])
51
52/// SHA-256 = 32 bytes of binary = 64 printable characters.
53#define DIGEST_HASH_TO_STRING_LENGTH 64
54
55/*
56 Various hashes considered for digests.
57
58 MD5:
59 - 128 bits
60 - used up to MySQL 5.7
61 - abandoned in MySQL 8.0, non FIPS compliant.
62
63 SHA1:
64 - 160 bits
65 - non FIPS compliant in strict mode
66 - not used
67
68 SHA2-224
69 - 224 bits
70 - non FIPS compliant in strict mode
71 - not used
72
73 SHA2-256
74 - 256 bits
75 - FIPS compliant
76 - Used starting with MySQL 8.0
77
78 SHA2-384
79 - 384 bits
80
81 SHA2-512
82 - 512 bits
83*/
84
85/**
86 DIGEST hash size, in bytes.
87 256 bits, for SHA256.
88*/
89#define DIGEST_HASH_SIZE 32
90
92
93/**
94 Structure to store token count/array for a statement
95 on which digest is to be calculated.
96*/
98 bool m_full;
100 unsigned char m_hash[DIGEST_HASH_SIZE];
101 /** Character set number. */
103 /**
104 Token array.
105 Token array is an array of bytes to store tokens received during parsing.
106 Following is the way token array is formed.
107 ... &lt;non-id-token&gt; &lt;non-id-token&gt; &lt;id-token&gt;
108 &lt;id_len&gt; &lt;id_text&gt; ... For Example: SELECT * FROM T1;
109 &lt;SELECT_TOKEN&gt; &lt;*&gt; &lt;FROM_TOKEN&gt; &lt;ID_TOKEN&gt; &lt;2&gt;
110 &lt;T1&gt;
111
112 @note Only the first @c m_byte_count bytes are initialized,
113 out of @c m_token_array_length.
114 */
115 unsigned char *m_token_array;
116 /* Length of the token array to be considered for DIGEST_TEXT calculation. */
118
119 sql_digest_storage() { reset(nullptr, 0); }
120
121 inline void reset(unsigned char *token_array, size_t length) {
122 m_token_array = token_array;
124 reset();
125 }
126
127 inline void reset() {
128 m_full = false;
129 m_byte_count = 0;
131 memset(m_hash, 0, DIGEST_HASH_SIZE);
132 }
133
134 inline bool is_empty() { return (m_byte_count == 0); }
135
136 inline void copy(const sql_digest_storage *from) {
137 /*
138 Keep in mind this is a dirty copy of something that may change,
139 as the thread producing the digest is executing concurrently,
140 without any lock enforced.
141 */
142 size_t byte_count_copy = m_token_array_length < from->m_byte_count
144 : from->m_byte_count;
145
146 if (byte_count_copy > 0) {
147 m_full = from->m_full;
148 m_byte_count = byte_count_copy;
151 memcpy(m_hash, from->m_hash, DIGEST_HASH_SIZE);
152 } else {
153 m_full = false;
154 m_byte_count = 0;
156 }
157 }
158};
160
161/**
162 Compute a digest hash.
163 @param digest_storage The digest
164 @param [out] hash The computed digest hash. This parameter is a buffer of size
165 @c DIGEST_HASH_SIZE.
166*/
167void compute_digest_hash(const sql_digest_storage *digest_storage,
168 unsigned char *hash);
169
170/**
171 Compute a digest text.
172 A 'digest text' is a textual representation of a query,
173 where:
174 - comments are removed,
175 - non significant spaces are removed,
176 - literal values are replaced with a special '?' marker,
177 - lists of values are collapsed using a shorter notation
178 @param digest_storage The digest
179 @param [out] digest_text The digest text
180*/
181void compute_digest_text(const sql_digest_storage *digest_storage,
182 String *digest_text);
183
184#endif
Using this class is fraught with peril, and you need to be very careful when doing so.
Definition: sql_string.h:166
Some integer typedefs for easier portability.
bool length(const dd::Spatial_reference_system *srs, const Geometry *g1, double *length, bool *null) noexcept
Computes the length of linestrings and multilinestrings.
Definition: length.cc:75
void compute_digest_hash(const sql_digest_storage *digest_storage, unsigned char *hash)
Compute a digest hash.
Definition: sql_digest.cc:158
void compute_digest_text(const sql_digest_storage *digest_storage, String *digest_text)
Compute a digest text.
Definition: sql_digest.cc:169
ulong get_max_digest_length()
Definition: sql_digest.cc:49
#define DIGEST_HASH_SIZE
DIGEST hash size, in bytes.
Definition: sql_digest.h:89
Structure to store token count/array for a statement on which digest is to be calculated.
Definition: sql_digest.h:97
void copy(const sql_digest_storage *from)
Definition: sql_digest.h:136
uint m_charset_number
Character set number.
Definition: sql_digest.h:102
sql_digest_storage()
Definition: sql_digest.h:119
size_t m_byte_count
Definition: sql_digest.h:99
unsigned char m_hash[DIGEST_HASH_SIZE]
Definition: sql_digest.h:100
bool m_full
Definition: sql_digest.h:98
unsigned char * m_token_array
Token array.
Definition: sql_digest.h:115
void reset(unsigned char *token_array, size_t length)
Definition: sql_digest.h:121
bool is_empty()
Definition: sql_digest.h:134
void reset()
Definition: sql_digest.h:127
size_t m_token_array_length
Definition: sql_digest.h:117
unsigned int uint
Definition: uca-dump.cc:29