1/*
2 * md5.c:   checksum routines
3 *
4 * ====================================================================
5 *    Licensed to the Apache Software Foundation (ASF) under one
6 *    or more contributor license agreements.  See the NOTICE file
7 *    distributed with this work for additional information
8 *    regarding copyright ownership.  The ASF licenses this file
9 *    to you under the Apache License, Version 2.0 (the
10 *    "License"); you may not use this file except in compliance
11 *    with the License.  You may obtain a copy of the License at
12 *
13 *      http://www.apache.org/licenses/LICENSE-2.0
14 *
15 *    Unless required by applicable law or agreed to in writing,
16 *    software distributed under the License is distributed on an
17 *    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
18 *    KIND, either express or implied.  See the License for the
19 *    specific language governing permissions and limitations
20 *    under the License.
21 * ====================================================================
22 */
23
24
25#include <apr_md5.h>
26#include "md5.h"
27#include "svn_md5.h"
28
29
30
31/* The MD5 digest for the empty string. */
32static const unsigned char svn_md5__empty_string_digest_array[] = {
33  0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
34  0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e
35};
36
37const unsigned char *
38svn_md5__empty_string_digest(void)
39{
40  return svn_md5__empty_string_digest_array;
41}
42
43
44const char *
45svn_md5__digest_to_cstring_display(const unsigned char digest[],
46                                   apr_pool_t *pool)
47{
48  static const char *hex = "0123456789abcdef";
49  char *str = apr_palloc(pool, (APR_MD5_DIGESTSIZE * 2) + 1);
50  int i;
51
52  for (i = 0; i < APR_MD5_DIGESTSIZE; i++)
53    {
54      str[i*2]   = hex[digest[i] >> 4];
55      str[i*2+1] = hex[digest[i] & 0x0f];
56    }
57  str[i*2] = '\0';
58
59  return str;
60}
61
62
63const char *
64svn_md5__digest_to_cstring(const unsigned char digest[], apr_pool_t *pool)
65{
66  static const unsigned char zeros_digest[APR_MD5_DIGESTSIZE] = { 0 };
67
68  if (memcmp(digest, zeros_digest, APR_MD5_DIGESTSIZE) != 0)
69    return svn_md5__digest_to_cstring_display(digest, pool);
70  else
71    return NULL;
72}
73
74
75svn_boolean_t
76svn_md5__digests_match(const unsigned char d1[], const unsigned char d2[])
77{
78  static const unsigned char zeros[APR_MD5_DIGESTSIZE] = { 0 };
79
80  return ((memcmp(d1, zeros, APR_MD5_DIGESTSIZE) == 0)
81          || (memcmp(d2, zeros, APR_MD5_DIGESTSIZE) == 0)
82          || (memcmp(d1, d2, APR_MD5_DIGESTSIZE) == 0));
83}
84
85/* These are all deprecated, and just wrap the internal functions defined
86   above. */
87const unsigned char *
88svn_md5_empty_string_digest(void)
89{
90  return svn_md5__empty_string_digest();
91}
92
93const char *
94svn_md5_digest_to_cstring_display(const unsigned char digest[],
95                                  apr_pool_t *pool)
96{
97  return svn_md5__digest_to_cstring_display(digest, pool);
98}
99
100const char *
101svn_md5_digest_to_cstring(const unsigned char digest[], apr_pool_t *pool)
102{
103  return svn_md5__digest_to_cstring(digest, pool);
104}
105
106svn_boolean_t
107svn_md5_digests_match(const unsigned char d1[], const unsigned char d2[])
108{
109  return svn_md5__digests_match(d1, d2);
110}
111