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 66/* Size of an SSL signature: MD5+SHA1 */ 67#define SSL_SIG_LENGTH 36 68 69int RSA_sign(int type, const unsigned char *m, unsigned int m_len, 70 unsigned char *sigret, unsigned int *siglen, RSA *rsa) 71 { 72 X509_SIG sig; 73 ASN1_TYPE parameter; 74 int i,j,ret=1; 75 unsigned char *p, *tmps = NULL; 76 const unsigned char *s = NULL; 77 X509_ALGOR algor; 78 ASN1_OCTET_STRING digest; 79 if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_sign) 80 { 81 return rsa->meth->rsa_sign(type, m, m_len, 82 sigret, siglen, rsa); 83 } 84 /* Special case: SSL signature, just check the length */ 85 if(type == NID_md5_sha1) { 86 if(m_len != SSL_SIG_LENGTH) { 87 RSAerr(RSA_F_RSA_SIGN,RSA_R_INVALID_MESSAGE_LENGTH); 88 return(0); 89 } 90 i = SSL_SIG_LENGTH; 91 s = m; 92 } else { 93 /* NB: in FIPS mode block anything that isn't a TLS signature */ 94#ifdef OPENSSL_FIPS 95 if(FIPS_mode() && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW)) 96 { 97 RSAerr(RSA_F_RSA_SIGN, RSA_R_OPERATION_NOT_ALLOWED_IN_FIPS_MODE); 98 return 0; 99 } 100#endif 101 sig.algor= &algor; 102 sig.algor->algorithm=OBJ_nid2obj(type); 103 if (sig.algor->algorithm == NULL) 104 { 105 RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE); 106 return(0); 107 } 108 if (sig.algor->algorithm->length == 0) 109 { 110 RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD); 111 return(0); 112 } 113 parameter.type=V_ASN1_NULL; 114 parameter.value.ptr=NULL; 115 sig.algor->parameter= ¶meter; 116 117 sig.digest= &digest; 118 sig.digest->data=(unsigned char *)m; /* TMP UGLY CAST */ 119 sig.digest->length=m_len; 120 121 i=i2d_X509_SIG(&sig,NULL); 122 } 123 j=RSA_size(rsa); 124 if (i > (j-RSA_PKCS1_PADDING_SIZE)) 125 { 126 RSAerr(RSA_F_RSA_SIGN,RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY); 127 return(0); 128 } 129 if(type != NID_md5_sha1) { 130 tmps=(unsigned char *)OPENSSL_malloc((unsigned int)j+1); 131 if (tmps == NULL) 132 { 133 RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE); 134 return(0); 135 } 136 p=tmps; 137 i2d_X509_SIG(&sig,&p); 138 s=tmps; 139 } 140#ifdef OPENSSL_FIPS 141 /* Bypass algorithm blocking: this is allowed if we get this far */ 142 i=rsa->meth->rsa_priv_enc(i,s,sigret,rsa,RSA_PKCS1_PADDING); 143#else 144 i=RSA_private_encrypt(i,s,sigret,rsa,RSA_PKCS1_PADDING); 145#endif 146 if (i <= 0) 147 ret=0; 148 else 149 *siglen=i; 150 151 if(type != NID_md5_sha1) { 152 OPENSSL_cleanse(tmps,(unsigned int)j+1); 153 OPENSSL_free(tmps); 154 } 155 return(ret); 156 } 157 158int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len, 159 unsigned char *sigbuf, unsigned int siglen, RSA *rsa) 160 { 161 int i,ret=0,sigtype; 162 unsigned char *s; 163 X509_SIG *sig=NULL; 164 165 if (siglen != (unsigned int)RSA_size(rsa)) 166 { 167 RSAerr(RSA_F_RSA_VERIFY,RSA_R_WRONG_SIGNATURE_LENGTH); 168 return(0); 169 } 170 171 if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_verify) 172 { 173 return rsa->meth->rsa_verify(dtype, m, m_len, 174 sigbuf, siglen, rsa); 175 } 176 177 s=(unsigned char *)OPENSSL_malloc((unsigned int)siglen); 178 if (s == NULL) 179 { 180 RSAerr(RSA_F_RSA_VERIFY,ERR_R_MALLOC_FAILURE); 181 goto err; 182 } 183 if(dtype == NID_md5_sha1) 184 { 185 if (m_len != SSL_SIG_LENGTH) 186 { 187 RSAerr(RSA_F_RSA_VERIFY,RSA_R_INVALID_MESSAGE_LENGTH); 188 goto err; 189 } 190 } 191 /* NB: in FIPS mode block anything that isn't a TLS signature */ 192#ifdef OPENSSL_FIPS 193 else if(FIPS_mode() && !(rsa->flags & RSA_FLAG_NON_FIPS_ALLOW)) 194 { 195 RSAerr(RSA_F_RSA_VERIFY, RSA_R_OPERATION_NOT_ALLOWED_IN_FIPS_MODE); 196 return 0; 197 } 198 /* Bypass algorithm blocking: this is allowed */ 199 i=rsa->meth->rsa_pub_dec((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING); 200#else 201 i=RSA_public_decrypt((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING); 202#endif 203 204 if (i <= 0) goto err; 205 206 /* Special case: SSL signature */ 207 if(dtype == NID_md5_sha1) { 208 if((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH)) 209 RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 210 else ret = 1; 211 } else { 212 const unsigned char *p=s; 213 sig=d2i_X509_SIG(NULL,&p,(long)i); 214 215 if (sig == NULL) goto err; 216 217 /* Excess data can be used to create forgeries */ 218 if(p != s+i) 219 { 220 RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 221 goto err; 222 } 223 224 /* Parameters to the signature algorithm can also be used to 225 create forgeries */ 226 if(sig->algor->parameter 227 && ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL) 228 { 229 RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 230 goto err; 231 } 232 233 sigtype=OBJ_obj2nid(sig->algor->algorithm); 234 235 236 #ifdef RSA_DEBUG 237 /* put a backward compatibility flag in EAY */ 238 fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype), 239 OBJ_nid2ln(dtype)); 240 #endif 241 if (sigtype != dtype) 242 { 243 if (((dtype == NID_md5) && 244 (sigtype == NID_md5WithRSAEncryption)) || 245 ((dtype == NID_md2) && 246 (sigtype == NID_md2WithRSAEncryption))) 247 { 248 /* ok, we will let it through */ 249#if !defined(OPENSSL_NO_STDIO) && !defined(OPENSSL_SYS_WIN16) 250 fprintf(stderr,"signature has problems, re-make with post SSLeay045\n"); 251#endif 252 } 253 else 254 { 255 RSAerr(RSA_F_RSA_VERIFY, 256 RSA_R_ALGORITHM_MISMATCH); 257 goto err; 258 } 259 } 260 if ( ((unsigned int)sig->digest->length != m_len) || 261 (memcmp(m,sig->digest->data,m_len) != 0)) 262 { 263 RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 264 } 265 else 266 ret=1; 267 } 268err: 269 if (sig != NULL) X509_SIG_free(sig); 270 if (s != NULL) 271 { 272 OPENSSL_cleanse(s,(unsigned int)siglen); 273 OPENSSL_free(s); 274 } 275 return(ret); 276 } 277 278