1 /* crypto/rsa/rsa_ssl.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
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
65 int RSA_padding_add_SSLv23(unsigned char *to, int tlen,
66 const unsigned char *from, int flen)
67 {
68 int i,j;
69 unsigned char *p;
70
71 if (flen > (tlen-11))
72 {
73 RSAerr(RSA_F_RSA_PADDING_ADD_SSLV23,RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
74 return(0);
75 }
76
77 p=(unsigned char *)to;
78
79 *(p++)=0;
80 *(p++)=2; /* Public Key BT (Block Type) */
81
82 /* pad out with non-zero random data */
83 j=tlen-3-8-flen;
84
85 if (RAND_bytes(p,j) <= 0)
86 return(0);
87 for (i=0; i<j; i++)
88 {
89 if (*p == '\0')
90 do {
91 if (RAND_bytes(p,1) <= 0)
92 return(0);
93 } while (*p == '\0');
94 p++;
95 }
96
97 memset(p,3,8);
98 p+=8;
99 *(p++)='\0';
100
101 memcpy(p,from,(unsigned int)flen);
102 return(1);
103 }
104
105 int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
106 const unsigned char *from, int flen, int num)
107 {
108 int i,j,k;
109 const unsigned char *p;
110
111 p=from;
112 if (flen < 10)
113 {
114 RSAerr(RSA_F_RSA_PADDING_CHECK_SSLV23,RSA_R_DATA_TOO_SMALL);
115 return(-1);
116 }
117 if ((num != (flen+1)) || (*(p++) != 02))
118 {
119 RSAerr(RSA_F_RSA_PADDING_CHECK_SSLV23,RSA_R_BLOCK_TYPE_IS_NOT_02);
120 return(-1);
121 }
122
123 /* scan over padding data */
124 j=flen-1; /* one for type */
125 for (i=0; i<j; i++)
126 if (*(p++) == 0) break;
127
128 if ((i == j) || (i < 8))
129 {
130 RSAerr(RSA_F_RSA_PADDING_CHECK_SSLV23,RSA_R_NULL_BEFORE_BLOCK_MISSING);
131 return(-1);
132 }
133 for (k = -9; k<-1; k++)
134 {
135 if (p[k] != 0x03) break;
136 }
137 if (k == -1)
138 {
139 RSAerr(RSA_F_RSA_PADDING_CHECK_SSLV23,RSA_R_SSLV3_ROLLBACK_ATTACK);
140 return(-1);
141 }
142
143 i++; /* Skip over the '\0' */
144 j-=i;
145 if (j > tlen)
146 {
147 RSAerr(RSA_F_RSA_PADDING_CHECK_SSLV23,RSA_R_DATA_TOO_LARGE);
148 return(-1);
149 }
150 memcpy(to,p,(unsigned int)j);
151
152 return(j);
153 }