xref: /netbsd-src/crypto/external/bsd/heimdal/dist/lib/krb5/crypto-des-common.c (revision d3273b5b76f5afaafe308cead5511dbb8df8c5e9)
1 /*	$NetBSD: crypto-des-common.c,v 1.2 2017/01/28 21:31:49 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
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  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 /* Functions which are used by both single and triple DES enctypes */
37 
38 #include "krb5_locl.h"
39 
40 /*
41  * A = A xor B. A & B are 8 bytes.
42  */
43 
44 KRB5_LIB_FUNCTION void KRB5_LIB_CALL
45 _krb5_xor8(unsigned char *a, const unsigned char *b)
46 {
47     a[0] ^= b[0];
48     a[1] ^= b[1];
49     a[2] ^= b[2];
50     a[3] ^= b[3];
51     a[4] ^= b[4];
52     a[5] ^= b[5];
53     a[6] ^= b[6];
54     a[7] ^= b[7];
55 }
56 
57 #if defined(DES3_OLD_ENCTYPE) || defined(HEIM_WEAK_CRYPTO)
58 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
59 _krb5_des_checksum(krb5_context context,
60 		   const EVP_MD *evp_md,
61 		   struct _krb5_key_data *key,
62 		   const void *data,
63 		   size_t len,
64 		   Checksum *cksum)
65 {
66     struct _krb5_evp_schedule *ctx = key->schedule->data;
67     EVP_MD_CTX *m;
68     DES_cblock ivec;
69     unsigned char *p = cksum->checksum.data;
70 
71     krb5_generate_random_block(p, 8);
72 
73     m = EVP_MD_CTX_create();
74     if (m == NULL)
75 	return krb5_enomem(context);
76 
77     EVP_DigestInit_ex(m, evp_md, NULL);
78     EVP_DigestUpdate(m, p, 8);
79     EVP_DigestUpdate(m, data, len);
80     EVP_DigestFinal_ex (m, p + 8, NULL);
81     EVP_MD_CTX_destroy(m);
82     memset (&ivec, 0, sizeof(ivec));
83     EVP_CipherInit_ex(&ctx->ectx, NULL, NULL, NULL, (void *)&ivec, -1);
84     EVP_Cipher(&ctx->ectx, p, p, 24);
85 
86     return 0;
87 }
88 
89 KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
90 _krb5_des_verify(krb5_context context,
91 		 const EVP_MD *evp_md,
92 		 struct _krb5_key_data *key,
93 		 const void *data,
94 		 size_t len,
95 		 Checksum *C)
96 {
97     struct _krb5_evp_schedule *ctx = key->schedule->data;
98     EVP_MD_CTX *m;
99     unsigned char tmp[24];
100     unsigned char res[16];
101     DES_cblock ivec;
102     krb5_error_code ret = 0;
103 
104     m = EVP_MD_CTX_create();
105     if (m == NULL)
106 	return krb5_enomem(context);
107 
108     memset(&ivec, 0, sizeof(ivec));
109     EVP_CipherInit_ex(&ctx->dctx, NULL, NULL, NULL, (void *)&ivec, -1);
110     EVP_Cipher(&ctx->dctx, tmp, C->checksum.data, 24);
111 
112     EVP_DigestInit_ex(m, evp_md, NULL);
113     EVP_DigestUpdate(m, tmp, 8); /* confounder */
114     EVP_DigestUpdate(m, data, len);
115     EVP_DigestFinal_ex (m, res, NULL);
116     EVP_MD_CTX_destroy(m);
117     if(ct_memcmp(res, tmp + 8, sizeof(res)) != 0) {
118 	krb5_clear_error_message (context);
119 	ret = KRB5KRB_AP_ERR_BAD_INTEGRITY;
120     }
121     memset(tmp, 0, sizeof(tmp));
122     memset(res, 0, sizeof(res));
123     return ret;
124 }
125 
126 #endif
127 
128 static krb5_error_code
129 RSA_MD5_checksum(krb5_context context,
130 		 struct _krb5_key_data *key,
131 		 const void *data,
132 		 size_t len,
133 		 unsigned usage,
134 		 Checksum *C)
135 {
136     if (EVP_Digest(data, len, C->checksum.data, NULL, EVP_md5(), NULL) != 1)
137 	krb5_abortx(context, "md5 checksum failed");
138     return 0;
139 }
140 
141 struct _krb5_checksum_type _krb5_checksum_rsa_md5 = {
142     CKSUMTYPE_RSA_MD5,
143     "rsa-md5",
144     64,
145     16,
146     F_CPROOF,
147     RSA_MD5_checksum,
148     NULL
149 };
150