1 /* rsa_x931.c */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3 * project 2005.
4 */
5 /* ====================================================================
6 * Copyright (c) 2005 The OpenSSL Project. 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
17 * the documentation and/or other materials provided with the
18 * distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgment:
22 * "This product includes software developed by the OpenSSL Project
23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 * endorse or promote products derived from this software without
27 * prior written permission. For written permission, please contact
28 * licensing@OpenSSL.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 * nor may "OpenSSL" appear in their names without prior written
32 * permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 * acknowledgment:
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com). This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59 #include <stdio.h>
60 #include "cryptlib.h"
61 #include <openssl/bn.h>
62 #include <openssl/rsa.h>
63 #include <openssl/rand.h>
64 #include <openssl/objects.h>
65
66 int RSA_padding_add_X931(unsigned char *to, int tlen,
67 const unsigned char *from, int flen)
68 {
69 int j;
70 unsigned char *p;
71
72 /* Absolute minimum amount of padding is 1 header nibble, 1 padding
73 * nibble and 2 trailer bytes: but 1 hash if is already in 'from'.
74 */
75
76 j = tlen - flen - 2;
77
78 if (j < 0)
79 {
80 RSAerr(RSA_F_RSA_PADDING_ADD_X931,RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
81 return -1;
82 }
83
84 p=(unsigned char *)to;
85
86 /* If no padding start and end nibbles are in one byte */
87 if (j == 0)
88 *p++ = 0x6A;
89 else
90 {
91 *p++ = 0x6B;
92 if (j > 1)
93 {
94 memset(p, 0xBB, j - 1);
95 p += j - 1;
96 }
97 *p++ = 0xBA;
98 }
99 memcpy(p,from,(unsigned int)flen);
100 p += flen;
101 *p = 0xCC;
102 return(1);
103 }
104
105 int RSA_padding_check_X931(unsigned char *to, int tlen,
106 const unsigned char *from, int flen, int num)
107 {
108 int i = 0,j;
109 const unsigned char *p;
110
111 p=from;
112 if ((num != flen) || ((*p != 0x6A) && (*p != 0x6B)))
113 {
114 RSAerr(RSA_F_RSA_PADDING_CHECK_X931,RSA_R_INVALID_HEADER);
115 return -1;
116 }
117
118 if (*p++ == 0x6B)
119 {
120 j=flen-3;
121 for (i = 0; i < j; i++)
122 {
123 unsigned char c = *p++;
124 if (c == 0xBA)
125 break;
126 if (c != 0xBB)
127 {
128 RSAerr(RSA_F_RSA_PADDING_CHECK_X931,
129 RSA_R_INVALID_PADDING);
130 return -1;
131 }
132 }
133
134 j -= i;
135
136 if (i == 0)
137 {
138 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_PADDING);
139 return -1;
140 }
141
142 }
143 else j = flen - 2;
144
145 if (p[j] != 0xCC)
146 {
147 RSAerr(RSA_F_RSA_PADDING_CHECK_X931, RSA_R_INVALID_TRAILER);
148 return -1;
149 }
150
151 memcpy(to,p,(unsigned int)j);
152
153 return(j);
154 }
155
156 /* Translate between X931 hash ids and NIDs */
157
158 int RSA_X931_hash_id(int nid)
159 {
160 switch (nid)
161 {
162 case NID_sha1:
163 return 0x33;
164
165 case NID_sha256:
166 return 0x34;
167
168 case NID_sha384:
169 return 0x36;
170
171 case NID_sha512:
172 return 0x35;
173
174 }
175 return -1;
176 }