1 /* crypto/rsa/rsa_sign.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 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 } 145 146 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 } 272 273 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
