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 #ifdef OPENSSL_FIPS 81 if (FIPS_mode() && !(rsa->meth->flags & RSA_FLAG_FIPS_METHOD) 82 && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW)) 83 { 84 RSAerr(RSA_F_RSA_SIGN, RSA_R_NON_FIPS_RSA_METHOD); 85 return 0; 86 } 87 #endif 88 if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_sign) 89 { 90 return rsa->meth->rsa_sign(type, m, m_len, 91 sigret, siglen, rsa); 92 } 93 /* Special case: SSL signature, just check the length */ 94 if(type == NID_md5_sha1) { 95 if(m_len != SSL_SIG_LENGTH) { 96 RSAerr(RSA_F_RSA_SIGN,RSA_R_INVALID_MESSAGE_LENGTH); 97 return(0); 98 } 99 i = SSL_SIG_LENGTH; 100 s = m; 101 } else { 102 sig.algor= &algor; 103 sig.algor->algorithm=OBJ_nid2obj(type); 104 if (sig.algor->algorithm == NULL) 105 { 106 RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE); 107 return(0); 108 } 109 if (sig.algor->algorithm->length == 0) 110 { 111 RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD); 112 return(0); 113 } 114 parameter.type=V_ASN1_NULL; 115 parameter.value.ptr=NULL; 116 sig.algor->parameter= ¶meter; 117 118 sig.digest= &digest; 119 sig.digest->data=(unsigned char *)m; /* TMP UGLY CAST */ 120 sig.digest->length=m_len; 121 122 i=i2d_X509_SIG(&sig,NULL); 123 } 124 j=RSA_size(rsa); 125 if (i > (j-RSA_PKCS1_PADDING_SIZE)) 126 { 127 RSAerr(RSA_F_RSA_SIGN,RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY); 128 return(0); 129 } 130 if(type != NID_md5_sha1) { 131 tmps=(unsigned char *)OPENSSL_malloc((unsigned int)j+1); 132 if (tmps == NULL) 133 { 134 RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE); 135 return(0); 136 } 137 p=tmps; 138 i2d_X509_SIG(&sig,&p); 139 s=tmps; 140 } 141 i=RSA_private_encrypt(i,s,sigret,rsa,RSA_PKCS1_PADDING); 142 if (i <= 0) 143 ret=0; 144 else 145 *siglen=i; 146 147 if(type != NID_md5_sha1) { 148 OPENSSL_cleanse(tmps,(unsigned int)j+1); 149 OPENSSL_free(tmps); 150 } 151 return(ret); 152 } 153 154 int int_rsa_verify(int dtype, const unsigned char *m, 155 unsigned int m_len, 156 unsigned char *rm, size_t *prm_len, 157 const unsigned char *sigbuf, size_t siglen, 158 RSA *rsa) 159 { 160 int i,ret=0,sigtype; 161 unsigned char *s; 162 X509_SIG *sig=NULL; 163 164 #ifdef OPENSSL_FIPS 165 if (FIPS_mode() && !(rsa->meth->flags & RSA_FLAG_FIPS_METHOD) 166 && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW)) 167 { 168 RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_NON_FIPS_RSA_METHOD); 169 return 0; 170 } 171 #endif 172 173 if (siglen != (unsigned int)RSA_size(rsa)) 174 { 175 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_WRONG_SIGNATURE_LENGTH); 176 return(0); 177 } 178 179 if((dtype == NID_md5_sha1) && rm) 180 { 181 i = RSA_public_decrypt((int)siglen, 182 sigbuf,rm,rsa,RSA_PKCS1_PADDING); 183 if (i <= 0) 184 return 0; 185 *prm_len = i; 186 return 1; 187 } 188 189 s=(unsigned char *)OPENSSL_malloc((unsigned int)siglen); 190 if (s == NULL) 191 { 192 RSAerr(RSA_F_INT_RSA_VERIFY,ERR_R_MALLOC_FAILURE); 193 goto err; 194 } 195 if((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH) ) { 196 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_INVALID_MESSAGE_LENGTH); 197 goto err; 198 } 199 i=RSA_public_decrypt((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING); 200 201 if (i <= 0) goto err; 202 /* Oddball MDC2 case: signature can be OCTET STRING. 203 * check for correct tag and length octets. 204 */ 205 if (dtype == NID_mdc2 && i == 18 && s[0] == 0x04 && s[1] == 0x10) 206 { 207 if (rm) 208 { 209 memcpy(rm, s + 2, 16); 210 *prm_len = 16; 211 ret = 1; 212 } 213 else if(memcmp(m, s + 2, 16)) 214 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 215 else 216 ret = 1; 217 } 218 219 /* Special case: SSL signature */ 220 if(dtype == NID_md5_sha1) { 221 if((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH)) 222 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 223 else ret = 1; 224 } else { 225 const unsigned char *p=s; 226 sig=d2i_X509_SIG(NULL,&p,(long)i); 227 228 if (sig == NULL) goto err; 229 230 /* Excess data can be used to create forgeries */ 231 if(p != s+i) 232 { 233 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 234 goto err; 235 } 236 237 /* Parameters to the signature algorithm can also be used to 238 create forgeries */ 239 if(sig->algor->parameter 240 && ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL) 241 { 242 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 243 goto err; 244 } 245 246 sigtype=OBJ_obj2nid(sig->algor->algorithm); 247 248 249 #ifdef RSA_DEBUG 250 /* put a backward compatibility flag in EAY */ 251 fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype), 252 OBJ_nid2ln(dtype)); 253 #endif 254 if (sigtype != dtype) 255 { 256 if (((dtype == NID_md5) && 257 (sigtype == NID_md5WithRSAEncryption)) || 258 ((dtype == NID_md2) && 259 (sigtype == NID_md2WithRSAEncryption))) 260 { 261 /* ok, we will let it through */ 262 #if !defined(OPENSSL_NO_STDIO) && !defined(OPENSSL_SYS_WIN16) 263 fprintf(stderr,"signature has problems, re-make with post SSLeay045\n"); 264 #endif 265 } 266 else 267 { 268 RSAerr(RSA_F_INT_RSA_VERIFY, 269 RSA_R_ALGORITHM_MISMATCH); 270 goto err; 271 } 272 } 273 if (rm) 274 { 275 const EVP_MD *md; 276 md = EVP_get_digestbynid(dtype); 277 if (md && (EVP_MD_size(md) != sig->digest->length)) 278 RSAerr(RSA_F_INT_RSA_VERIFY, 279 RSA_R_INVALID_DIGEST_LENGTH); 280 else 281 { 282 memcpy(rm, sig->digest->data, 283 sig->digest->length); 284 *prm_len = sig->digest->length; 285 ret = 1; 286 } 287 } 288 else if (((unsigned int)sig->digest->length != m_len) || 289 (memcmp(m,sig->digest->data,m_len) != 0)) 290 { 291 RSAerr(RSA_F_INT_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 292 } 293 else 294 ret=1; 295 } 296 err: 297 if (sig != NULL) X509_SIG_free(sig); 298 if (s != NULL) 299 { 300 OPENSSL_cleanse(s,(unsigned int)siglen); 301 OPENSSL_free(s); 302 } 303 return(ret); 304 } 305 306 int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len, 307 const unsigned char *sigbuf, unsigned int siglen, 308 RSA *rsa) 309 { 310 311 if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_verify) 312 { 313 return rsa->meth->rsa_verify(dtype, m, m_len, 314 sigbuf, siglen, rsa); 315 } 316 317 return int_rsa_verify(dtype, m, m_len, NULL, NULL, sigbuf, siglen, rsa); 318 } 319
