1 /* $OpenBSD: rsa_x931.c,v 1.10 2017/01/29 17:49:23 beck Exp $ */
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 <string.h>
61
62 #include <openssl/bn.h>
63 #include <openssl/err.h>
64 #include <openssl/objects.h>
65 #include <openssl/rsa.h>
66
67 int
RSA_padding_add_X931(unsigned char * to,int tlen,const unsigned char * from,int flen)68 RSA_padding_add_X931(unsigned char *to, int tlen, const unsigned char *from,
69 int flen)
70 {
71 int j;
72 unsigned char *p;
73
74 /*
75 * Absolute minimum amount of padding is 1 header nibble, 1 padding
76 * nibble and 2 trailer bytes: but 1 hash if is already in 'from'.
77 */
78 j = tlen - flen - 2;
79
80 if (j < 0) {
81 RSAerror(RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
82 return -1;
83 }
84
85 p = (unsigned char *)to;
86
87 /* If no padding start and end nibbles are in one byte */
88 if (j == 0)
89 *p++ = 0x6A;
90 else {
91 *p++ = 0x6B;
92 if (j > 1) {
93 memset(p, 0xBB, j - 1);
94 p += j - 1;
95 }
96 *p++ = 0xBA;
97 }
98 memcpy(p, from, flen);
99 p += flen;
100 *p = 0xCC;
101 return 1;
102 }
103
104 int
RSA_padding_check_X931(unsigned char * to,int tlen,const unsigned char * from,int flen,int num)105 RSA_padding_check_X931(unsigned char *to, int tlen, const unsigned char *from,
106 int flen, int num)
107 {
108 int i = 0, j;
109 const unsigned char *p = from;
110
111 if (num != flen || (*p != 0x6A && *p != 0x6B)) {
112 RSAerror(RSA_R_INVALID_HEADER);
113 return -1;
114 }
115
116 if (*p++ == 0x6B) {
117 j = flen - 3;
118 for (i = 0; i < j; i++) {
119 unsigned char c = *p++;
120 if (c == 0xBA)
121 break;
122 if (c != 0xBB) {
123 RSAerror(RSA_R_INVALID_PADDING);
124 return -1;
125 }
126 }
127
128 if (i == 0) {
129 RSAerror(RSA_R_INVALID_PADDING);
130 return -1;
131 }
132
133 j -= i;
134 } else
135 j = flen - 2;
136
137 if (j < 0 || p[j] != 0xCC) {
138 RSAerror(RSA_R_INVALID_TRAILER);
139 return -1;
140 }
141
142 memcpy(to, p, j);
143
144 return j;
145 }
146
147 /* Translate between X931 hash ids and NIDs */
148
149 int
RSA_X931_hash_id(int nid)150 RSA_X931_hash_id(int nid)
151 {
152 switch (nid) {
153 case NID_sha1:
154 return 0x33;
155 case NID_sha256:
156 return 0x34;
157 case NID_sha384:
158 return 0x36;
159 case NID_sha512:
160 return 0x35;
161 }
162
163 return -1;
164 }
165