1 /* crypto/rsa/rsa_sign.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/objects.h>
64 #include <openssl/x509.h>
65 #include "rsa_locl.h"
66
67 /* Size of an SSL signature: MD5+SHA1 */
68 #define SSL_SIG_LENGTH 36
69
RSA_sign(int type,const unsigned char * m,unsigned int m_len,unsigned char * sigret,unsigned int * siglen,RSA * rsa)70 int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
71 unsigned char *sigret, unsigned int *siglen, RSA *rsa)
72 {
73 X509_SIG sig;
74 ASN1_TYPE parameter;
75 int i,j,ret=1;
76 unsigned char *p, *tmps = NULL;
77 const unsigned char *s = NULL;
78 X509_ALGOR algor;
79 ASN1_OCTET_STRING digest;
80 if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_sign)
81 {
82 return rsa->meth->rsa_sign(type, m, m_len,
83 sigret, siglen, rsa);
84 }
85 /* Special case: SSL signature, just check the length */
86 if(type == NID_md5_sha1) {
87 if(m_len != SSL_SIG_LENGTH) {
88 RSAerr(RSA_F_RSA_SIGN,RSA_R_INVALID_MESSAGE_LENGTH);
89 return(0);
90 }
91 i = SSL_SIG_LENGTH;
92 s = m;
93 } else {
94 sig.algor= &algor;
95 sig.algor->algorithm=OBJ_nid2obj(type);
96 if (sig.algor->algorithm == NULL)
97 {
98 RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE);
99 return(0);
100 }
101 if (sig.algor->algorithm->length == 0)
102 {
103 RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
104 return(0);
105 }
106 parameter.type=V_ASN1_NULL;
107 parameter.value.ptr=NULL;
108 sig.algor->parameter= ¶meter;
109
110 sig.digest= &digest;
111 sig.digest->data=(unsigned char *)m; /* TMP UGLY CAST */
112 sig.digest->length=m_len;
113
114 i=i2d_X509_SIG(&sig,NULL);
115 }
116 j=RSA_size(rsa);
117 if (i > (j-RSA_PKCS1_PADDING_SIZE))
118 {
119 RSAerr(RSA_F_RSA_SIGN,RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
120 return(0);
121 }
122 if(type != NID_md5_sha1) {
123 tmps=(unsigned char *)OPENSSL_malloc((unsigned int)j+1);
124 if (tmps == NULL)
125 {
126 RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE);
127 return(0);
128 }
129 p=tmps;
130 i2d_X509_SIG(&sig,&p);
131 s=tmps;
132 }
133 i=RSA_private_encrypt(i,s,sigret,rsa,RSA_PKCS1_PADDING);
134 if (i <= 0)
135 ret=0;
136 else
137 *siglen=i;
138
139 if(type != NID_md5_sha1) {
140 OPENSSL_cleanse(tmps,(unsigned int)j+1);
141 OPENSSL_free(tmps);
142 }
143 return(ret);
144 }
145
int_rsa_verify(int dtype,const unsigned char * m,unsigned int m_len,unsigned char * rm,size_t * prm_len,const unsigned char * sigbuf,size_t siglen,RSA * rsa)146 int int_rsa_verify(int dtype, const unsigned char *m,
147 unsigned int m_len,
148 unsigned char *rm, size_t *prm_len,
149 const unsigned char *sigbuf, size_t siglen,
150 RSA *rsa)
151 {
152 int i,ret=0,sigtype;
153 unsigned char *s;
154 X509_SIG *sig=NULL;
155
156 if (siglen != (unsigned int)RSA_size(rsa))
157 {
158 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_WRONG_SIGNATURE_LENGTH);
159 return(0);
160 }
161
162 if((dtype == NID_md5_sha1) && rm)
163 {
164 i = RSA_public_decrypt((int)siglen,
165 sigbuf,rm,rsa,RSA_PKCS1_PADDING);
166 if (i <= 0)
167 return 0;
168 *prm_len = i;
169 return 1;
170 }
171
172 s=(unsigned char *)OPENSSL_malloc((unsigned int)siglen);
173 if (s == NULL)
174 {
175 RSAerr(RSA_F_INT_RSA_VERIFY,ERR_R_MALLOC_FAILURE);
176 goto err;
177 }
178 if((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH) ) {
179 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_INVALID_MESSAGE_LENGTH);
180 goto err;
181 }
182 i=RSA_public_decrypt((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING);
183
184 if (i <= 0) goto err;
185
186 /* Special case: SSL signature */
187 if(dtype == NID_md5_sha1) {
188 if((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH))
189 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
190 else ret = 1;
191 } else {
192 const unsigned char *p=s;
193 sig=d2i_X509_SIG(NULL,&p,(long)i);
194
195 if (sig == NULL) goto err;
196
197 /* Excess data can be used to create forgeries */
198 if(p != s+i)
199 {
200 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
201 goto err;
202 }
203
204 /* Parameters to the signature algorithm can also be used to
205 create forgeries */
206 if(sig->algor->parameter
207 && ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL)
208 {
209 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
210 goto err;
211 }
212
213 sigtype=OBJ_obj2nid(sig->algor->algorithm);
214
215
216 #ifdef RSA_DEBUG
217 /* put a backward compatibility flag in EAY */
218 fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype),
219 OBJ_nid2ln(dtype));
220 #endif
221 if (sigtype != dtype)
222 {
223 if (((dtype == NID_md5) &&
224 (sigtype == NID_md5WithRSAEncryption)) ||
225 ((dtype == NID_md2) &&
226 (sigtype == NID_md2WithRSAEncryption)))
227 {
228 /* ok, we will let it through */
229 #if !defined(OPENSSL_NO_STDIO) && !defined(OPENSSL_SYS_WIN16)
230 fprintf(stderr,"signature has problems, re-make with post SSLeay045\n");
231 #endif
232 }
233 else
234 {
235 RSAerr(RSA_F_INT_RSA_VERIFY,
236 RSA_R_ALGORITHM_MISMATCH);
237 goto err;
238 }
239 }
240 if (rm)
241 {
242 const EVP_MD *md;
243 md = EVP_get_digestbynid(dtype);
244 if (md && (EVP_MD_size(md) != sig->digest->length))
245 RSAerr(RSA_F_INT_RSA_VERIFY,
246 RSA_R_INVALID_DIGEST_LENGTH);
247 else
248 {
249 memcpy(rm, sig->digest->data,
250 sig->digest->length);
251 *prm_len = sig->digest->length;
252 ret = 1;
253 }
254 }
255 else if (((unsigned int)sig->digest->length != m_len) ||
256 (memcmp(m,sig->digest->data,m_len) != 0))
257 {
258 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
259 }
260 else
261 ret=1;
262 }
263 err:
264 if (sig != NULL) X509_SIG_free(sig);
265 if (s != NULL)
266 {
267 OPENSSL_cleanse(s,(unsigned int)siglen);
268 OPENSSL_free(s);
269 }
270 return(ret);
271 }
272
RSA_verify(int dtype,const unsigned char * m,unsigned int m_len,const unsigned char * sigbuf,unsigned int siglen,RSA * rsa)273 int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len,
274 const unsigned char *sigbuf, unsigned int siglen,
275 RSA *rsa)
276 {
277
278 if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_verify)
279 {
280 return rsa->meth->rsa_verify(dtype, m, m_len,
281 sigbuf, siglen, rsa);
282 }
283
284 return int_rsa_verify(dtype, m, m_len, NULL, NULL, sigbuf, siglen, rsa);
285 }
286