1/*
2 * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 *
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 * 3. Neither the name of the Institute nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34/* Functions which are used by both single and triple DES enctypes */
35
36#include "krb5_locl.h"
37
38/*
39 * A = A xor B. A & B are 8 bytes.
40 */
41
42void
43_krb5_xor (DES_cblock *key, const unsigned char *b)
44{
45    unsigned char *a = (unsigned char*)key;
46    a[0] ^= b[0];
47    a[1] ^= b[1];
48    a[2] ^= b[2];
49    a[3] ^= b[3];
50    a[4] ^= b[4];
51    a[5] ^= b[5];
52    a[6] ^= b[6];
53    a[7] ^= b[7];
54}
55
56#if defined(DES3_OLD_ENCTYPE) || defined(HEIM_WEAK_CRYPTO)
57krb5_error_code
58_krb5_des_checksum(krb5_context context,
59		   const EVP_MD *evp_md,
60		   struct _krb5_key_data *key,
61		   const void *data,
62		   size_t len,
63		   Checksum *cksum)
64{
65    struct _krb5_evp_schedule *ctx = key->schedule->data;
66    EVP_MD_CTX *m;
67    DES_cblock ivec;
68    unsigned char *p = cksum->checksum.data;
69
70    krb5_generate_random_block(p, 8);
71
72    m = EVP_MD_CTX_create();
73    if (m == NULL) {
74	krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
75	return ENOMEM;
76    }
77
78    EVP_DigestInit_ex(m, evp_md, NULL);
79    EVP_DigestUpdate(m, p, 8);
80    EVP_DigestUpdate(m, data, len);
81    EVP_DigestFinal_ex (m, p + 8, NULL);
82    EVP_MD_CTX_destroy(m);
83    memset (&ivec, 0, sizeof(ivec));
84    EVP_CipherInit_ex(&ctx->ectx, NULL, NULL, NULL, (void *)&ivec, -1);
85    EVP_Cipher(&ctx->ectx, p, p, 24);
86
87    return 0;
88}
89
90krb5_error_code
91_krb5_des_verify(krb5_context context,
92		 const EVP_MD *evp_md,
93		 struct _krb5_key_data *key,
94		 const void *data,
95		 size_t len,
96		 Checksum *C)
97{
98    struct _krb5_evp_schedule *ctx = key->schedule->data;
99    EVP_MD_CTX *m;
100    unsigned char tmp[24];
101    unsigned char res[16];
102    DES_cblock ivec;
103    krb5_error_code ret = 0;
104
105    m = EVP_MD_CTX_create();
106    if (m == NULL) {
107	krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", ""));
108	return ENOMEM;
109    }
110
111    memset(&ivec, 0, sizeof(ivec));
112    EVP_CipherInit_ex(&ctx->dctx, NULL, NULL, NULL, (void *)&ivec, -1);
113    EVP_Cipher(&ctx->dctx, tmp, C->checksum.data, 24);
114
115    EVP_DigestInit_ex(m, evp_md, NULL);
116    EVP_DigestUpdate(m, tmp, 8); /* confounder */
117    EVP_DigestUpdate(m, data, len);
118    EVP_DigestFinal_ex (m, res, NULL);
119    EVP_MD_CTX_destroy(m);
120    if(ct_memcmp(res, tmp + 8, sizeof(res)) != 0) {
121	krb5_clear_error_message (context);
122	ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
123    }
124    memset(tmp, 0, sizeof(tmp));
125    memset(res, 0, sizeof(res));
126    return ret;
127}
128
129#endif
130
131static krb5_error_code
132RSA_MD5_checksum(krb5_context context,
133		 struct _krb5_key_data *key,
134		 const void *data,
135		 size_t len,
136		 unsigned usage,
137		 Checksum *C)
138{
139    if (EVP_Digest(data, len, C->checksum.data, NULL, EVP_md5(), NULL) != 1)
140	krb5_abortx(context, "md5 checksum failed");
141    return 0;
142}
143
144struct _krb5_checksum_type _krb5_checksum_rsa_md5 = {
145    CKSUMTYPE_RSA_MD5,
146    "rsa-md5",
147    64,
148    16,
149    F_CPROOF,
150    RSA_MD5_checksum,
151    NULL
152};
153