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px-hmac.c
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1 /*
2  * px-hmac.c
3  * HMAC implementation.
4  *
5  * Copyright (c) 2001 Marko Kreen
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  * notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  * notice, this list of conditions and the following disclaimer in the
15  * documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * contrib/pgcrypto/px-hmac.c
30  */
31 
32 #include "postgres.h"
33 
34 #include "px.h"
35 
36 #define HMAC_IPAD 0x36
37 #define HMAC_OPAD 0x5C
38 
39 static unsigned
41 {
42  return px_md_result_size(h->md);
43 }
44 
45 static unsigned
47 {
48  return px_md_block_size(h->md);
49 }
50 
51 static void
52 hmac_init(PX_HMAC *h, const uint8 *key, unsigned klen)
53 {
54  unsigned bs,
55  i;
56  uint8 *keybuf;
57  PX_MD *md = h->md;
58 
59  bs = px_md_block_size(md);
60  keybuf = palloc0(bs);
61 
62  if (klen > bs)
63  {
64  px_md_update(md, key, klen);
65  px_md_finish(md, keybuf);
66  px_md_reset(md);
67  }
68  else
69  memcpy(keybuf, key, klen);
70 
71  for (i = 0; i < bs; i++)
72  {
73  h->p.ipad[i] = keybuf[i] ^ HMAC_IPAD;
74  h->p.opad[i] = keybuf[i] ^ HMAC_OPAD;
75  }
76 
77  px_memset(keybuf, 0, bs);
78  pfree(keybuf);
79 
80  px_md_update(md, h->p.ipad, bs);
81 }
82 
83 static void
85 {
86  PX_MD *md = h->md;
87  unsigned bs = px_md_block_size(md);
88 
89  px_md_reset(md);
90  px_md_update(md, h->p.ipad, bs);
91 }
92 
93 static void
94 hmac_update(PX_HMAC *h, const uint8 *data, unsigned dlen)
95 {
96  px_md_update(h->md, data, dlen);
97 }
98 
99 static void
101 {
102  PX_MD *md = h->md;
103  unsigned bs,
104  hlen;
105  uint8 *buf;
106 
107  bs = px_md_block_size(md);
108  hlen = px_md_result_size(md);
109 
110  buf = palloc(hlen);
111 
112  px_md_finish(md, buf);
113 
114  px_md_reset(md);
115  px_md_update(md, h->p.opad, bs);
116  px_md_update(md, buf, hlen);
117  px_md_finish(md, dst);
118 
119  px_memset(buf, 0, hlen);
120  pfree(buf);
121 }
122 
123 static void
125 {
126  unsigned bs;
127 
128  bs = px_md_block_size(h->md);
129  px_md_free(h->md);
130 
131  px_memset(h->p.ipad, 0, bs);
132  px_memset(h->p.opad, 0, bs);
133  pfree(h->p.ipad);
134  pfree(h->p.opad);
135  pfree(h);
136 }
137 
138 
139 /* PUBLIC FUNCTIONS */
140 
141 int
142 px_find_hmac(const char *name, PX_HMAC **res)
143 {
144  int err;
145  PX_MD *md;
146  PX_HMAC *h;
147  unsigned bs;
148 
149  err = px_find_digest(name, &md);
150  if (err)
151  return err;
152 
153  bs = px_md_block_size(md);
154  if (bs < 2)
155  {
156  px_md_free(md);
158  }
159 
160  h = palloc(sizeof(*h));
161  h->p.ipad = palloc(bs);
162  h->p.opad = palloc(bs);
163  h->md = md;
164 
167  h->reset = hmac_reset;
168  h->update = hmac_update;
169  h->finish = hmac_finish;
170  h->free = hmac_free;
171  h->init = hmac_init;
172 
173  *res = h;
174 
175  return 0;
176 }
#define PXE_HASH_UNUSABLE_FOR_HMAC
Definition: px.h:55
static void hmac_init(PX_HMAC *h, const uint8 *key, unsigned klen)
Definition: px-hmac.c:52
#define HMAC_IPAD
Definition: px-hmac.c:36
#define px_md_update(md, data, dlen)
Definition: px.h:193
struct px_hmac::@13 p
unsigned char uint8
Definition: c.h:427
void(* free)(PX_HMAC *h)
Definition: px.h:127
static void hmac_free(PX_HMAC *h)
Definition: px-hmac.c:124
unsigned(* result_size)(PX_HMAC *h)
Definition: px.h:122
#define px_md_finish(md, buf)
Definition: px.h:194
#define px_md_block_size(md)
Definition: px.h:191
#define px_md_reset(md)
Definition: px.h:192
static void hmac_update(PX_HMAC *h, const uint8 *data, unsigned dlen)
Definition: px-hmac.c:94
static void hmac_finish(PX_HMAC *h, uint8 *dst)
Definition: px-hmac.c:100
PX_MD * md
Definition: px.h:130
void(* reset)(PX_HMAC *h)
Definition: px.h:124
void pfree(void *pointer)
Definition: mcxt.c:1057
#define px_md_result_size(md)
Definition: px.h:190
#define HMAC_OPAD
Definition: px-hmac.c:37
Definition: px.h:98
static char * buf
Definition: pg_test_fsync.c:68
int px_find_hmac(const char *name, PX_HMAC **res)
Definition: px-hmac.c:142
void(* update)(PX_HMAC *h, const uint8 *data, unsigned dlen)
Definition: px.h:125
void(* finish)(PX_HMAC *h, uint8 *dst)
Definition: px.h:126
uint8 * opad
Definition: px.h:135
static void hmac_reset(PX_HMAC *h)
Definition: px-hmac.c:84
#define px_md_free(md)
Definition: px.h:195
void * palloc0(Size size)
Definition: mcxt.c:981
static unsigned hmac_result_size(PX_HMAC *h)
Definition: px-hmac.c:40
void(* init)(PX_HMAC *h, const uint8 *key, unsigned klen)
Definition: px.h:128
static unsigned hmac_block_size(PX_HMAC *h)
Definition: px-hmac.c:46
const char * name
Definition: encode.c:561
uint8 * ipad
Definition: px.h:134
void * palloc(Size size)
Definition: mcxt.c:950
int i
unsigned(* block_size)(PX_HMAC *h)
Definition: px.h:123
Definition: px.h:120
int px_find_digest(const char *name, PX_MD **res)
Definition: internal.c:553
void px_memset(void *ptr, int c, size_t len)
Definition: px.c:127