1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
59 #include "internal/cryptlib.h"
60 #include <openssl/bn.h>
61 #include <openssl/rsa.h>
62 #include <openssl/objects.h>
63 #include <openssl/x509.h>
66 /* Size of an SSL signature: MD5+SHA1 */
67 #define SSL_SIG_LENGTH 36
69 int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
70 unsigned char *sigret, unsigned int *siglen, RSA *rsa)
75 unsigned char *p, *tmps = NULL;
76 const unsigned char *s = NULL;
78 ASN1_OCTET_STRING digest;
79 if (rsa->meth->rsa_sign) {
80 return rsa->meth->rsa_sign(type, m, m_len, sigret, siglen, rsa);
82 /* Special case: SSL signature, just check the length */
83 if (type == NID_md5_sha1) {
84 if (m_len != SSL_SIG_LENGTH) {
85 RSAerr(RSA_F_RSA_SIGN, RSA_R_INVALID_MESSAGE_LENGTH);
92 sig.algor->algorithm = OBJ_nid2obj(type);
93 if (sig.algor->algorithm == NULL) {
94 RSAerr(RSA_F_RSA_SIGN, RSA_R_UNKNOWN_ALGORITHM_TYPE);
97 if (OBJ_length(sig.algor->algorithm) == 0) {
98 RSAerr(RSA_F_RSA_SIGN,
99 RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
102 parameter.type = V_ASN1_NULL;
103 parameter.value.ptr = NULL;
104 sig.algor->parameter = ¶meter;
106 sig.digest = &digest;
107 sig.digest->data = (unsigned char *)m; /* TMP UGLY CAST */
108 sig.digest->length = m_len;
110 i = i2d_X509_SIG(&sig, NULL);
113 if (i > (j - RSA_PKCS1_PADDING_SIZE)) {
114 RSAerr(RSA_F_RSA_SIGN, RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
117 if (type != NID_md5_sha1) {
118 tmps = OPENSSL_malloc((unsigned int)j + 1);
120 RSAerr(RSA_F_RSA_SIGN, ERR_R_MALLOC_FAILURE);
124 i2d_X509_SIG(&sig, &p);
127 i = RSA_private_encrypt(i, s, sigret, rsa, RSA_PKCS1_PADDING);
133 if (type != NID_md5_sha1)
134 OPENSSL_clear_free(tmps, (unsigned int)j + 1);
139 * Check DigestInfo structure does not contain extraneous data by reencoding
140 * using DER and checking encoding against original.
142 static int rsa_check_digestinfo(X509_SIG *sig, const unsigned char *dinfo,
145 unsigned char *der = NULL;
148 derlen = i2d_X509_SIG(sig, &der);
151 if (derlen == dinfolen && !memcmp(dinfo, der, derlen))
153 OPENSSL_clear_free(der, derlen);
157 int int_rsa_verify(int dtype, const unsigned char *m,
159 unsigned char *rm, size_t *prm_len,
160 const unsigned char *sigbuf, size_t siglen, RSA *rsa)
162 int i, ret = 0, sigtype;
164 X509_SIG *sig = NULL;
166 if (siglen != (unsigned int)RSA_size(rsa)) {
167 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_WRONG_SIGNATURE_LENGTH);
171 if ((dtype == NID_md5_sha1) && rm) {
172 i = RSA_public_decrypt((int)siglen,
173 sigbuf, rm, rsa, RSA_PKCS1_PADDING);
180 s = OPENSSL_malloc((unsigned int)siglen);
182 RSAerr(RSA_F_INT_RSA_VERIFY, ERR_R_MALLOC_FAILURE);
185 if ((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH)) {
186 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_INVALID_MESSAGE_LENGTH);
189 i = RSA_public_decrypt((int)siglen, sigbuf, s, rsa, RSA_PKCS1_PADDING);
194 * Oddball MDC2 case: signature can be OCTET STRING. check for correct
195 * tag and length octets.
197 if (dtype == NID_mdc2 && i == 18 && s[0] == 0x04 && s[1] == 0x10) {
199 memcpy(rm, s + 2, 16);
202 } else if (memcmp(m, s + 2, 16)) {
203 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
207 } else if (dtype == NID_md5_sha1) {
208 /* Special case: SSL signature */
209 if ((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH))
210 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
214 const unsigned char *p = s;
215 sig = d2i_X509_SIG(NULL, &p, (long)i);
220 /* Excess data can be used to create forgeries */
221 if (p != s + i || !rsa_check_digestinfo(sig, s, i)) {
222 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
227 * Parameters to the signature algorithm can also be used to create
230 if (sig->algor->parameter
231 && ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL) {
232 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
236 sigtype = OBJ_obj2nid(sig->algor->algorithm);
238 if (sigtype != dtype) {
239 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_ALGORITHM_MISMATCH);
244 md = EVP_get_digestbynid(dtype);
245 if (md && (EVP_MD_size(md) != sig->digest->length))
246 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_INVALID_DIGEST_LENGTH);
248 memcpy(rm, sig->digest->data, sig->digest->length);
249 *prm_len = sig->digest->length;
252 } else if (((unsigned int)sig->digest->length != m_len) ||
253 (memcmp(m, sig->digest->data, m_len) != 0)) {
254 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE);
260 OPENSSL_clear_free(s, (unsigned int)siglen);
264 int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len,
265 const unsigned char *sigbuf, unsigned int siglen, RSA *rsa)
268 if (rsa->meth->rsa_verify) {
269 return rsa->meth->rsa_verify(dtype, m, m_len, sigbuf, siglen, rsa);
272 return int_rsa_verify(dtype, m, m_len, NULL, NULL, sigbuf, siglen, rsa);