rsa_sign.c revision 109998
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 <openssl/engine.h> 66 67/* Size of an SSL signature: MD5+SHA1 */ 68#define SSL_SIG_LENGTH 36 69 70int 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) 81 && ENGINE_get_RSA(rsa->engine)->rsa_sign) 82 return ENGINE_get_RSA(rsa->engine)->rsa_sign(type, 83 m, m_len, sigret, siglen, rsa); 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 sig.algor= &algor; 94 sig.algor->algorithm=OBJ_nid2obj(type); 95 if (sig.algor->algorithm == NULL) 96 { 97 RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE); 98 return(0); 99 } 100 if (sig.algor->algorithm->length == 0) 101 { 102 RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD); 103 return(0); 104 } 105 parameter.type=V_ASN1_NULL; 106 parameter.value.ptr=NULL; 107 sig.algor->parameter= ¶meter; 108 109 sig.digest= &digest; 110 sig.digest->data=(unsigned char *)m; /* TMP UGLY CAST */ 111 sig.digest->length=m_len; 112 113 i=i2d_X509_SIG(&sig,NULL); 114 } 115 j=RSA_size(rsa); 116 if (i > (j-RSA_PKCS1_PADDING_SIZE)) 117 { 118 RSAerr(RSA_F_RSA_SIGN,RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY); 119 return(0); 120 } 121 if(type != NID_md5_sha1) { 122 tmps=(unsigned char *)OPENSSL_malloc((unsigned int)j+1); 123 if (tmps == NULL) 124 { 125 RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE); 126 return(0); 127 } 128 p=tmps; 129 i2d_X509_SIG(&sig,&p); 130 s=tmps; 131 } 132 i=RSA_private_encrypt(i,s,sigret,rsa,RSA_PKCS1_PADDING); 133 if (i <= 0) 134 ret=0; 135 else 136 *siglen=i; 137 138 if(type != NID_md5_sha1) { 139 OPENSSL_cleanse(tmps,(unsigned int)j+1); 140 OPENSSL_free(tmps); 141 } 142 return(ret); 143 } 144 145int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len, 146 unsigned char *sigbuf, unsigned int siglen, RSA *rsa) 147 { 148 int i,ret=0,sigtype; 149 unsigned char *p,*s; 150 X509_SIG *sig=NULL; 151 152 if (siglen != (unsigned int)RSA_size(rsa)) 153 { 154 RSAerr(RSA_F_RSA_VERIFY,RSA_R_WRONG_SIGNATURE_LENGTH); 155 return(0); 156 } 157 158 if((rsa->flags & RSA_FLAG_SIGN_VER) 159 && ENGINE_get_RSA(rsa->engine)->rsa_verify) 160 return ENGINE_get_RSA(rsa->engine)->rsa_verify(dtype, 161 m, m_len, sigbuf, siglen, rsa); 162 163 s=(unsigned char *)OPENSSL_malloc((unsigned int)siglen); 164 if (s == NULL) 165 { 166 RSAerr(RSA_F_RSA_VERIFY,ERR_R_MALLOC_FAILURE); 167 goto err; 168 } 169 if((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH) ) { 170 RSAerr(RSA_F_RSA_VERIFY,RSA_R_INVALID_MESSAGE_LENGTH); 171 return(0); 172 } 173 i=RSA_public_decrypt((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING); 174 175 if (i <= 0) goto err; 176 177 /* Special case: SSL signature */ 178 if(dtype == NID_md5_sha1) { 179 if((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH)) 180 RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 181 else ret = 1; 182 } else { 183 p=s; 184 sig=d2i_X509_SIG(NULL,&p,(long)i); 185 186 if (sig == NULL) goto err; 187 sigtype=OBJ_obj2nid(sig->algor->algorithm); 188 189 190 #ifdef RSA_DEBUG 191 /* put a backward compatibility flag in EAY */ 192 fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype), 193 OBJ_nid2ln(dtype)); 194 #endif 195 if (sigtype != dtype) 196 { 197 if (((dtype == NID_md5) && 198 (sigtype == NID_md5WithRSAEncryption)) || 199 ((dtype == NID_md2) && 200 (sigtype == NID_md2WithRSAEncryption))) 201 { 202 /* ok, we will let it through */ 203#if !defined(OPENSSL_NO_STDIO) && !defined(OPENSSL_SYS_WIN16) 204 fprintf(stderr,"signature has problems, re-make with post SSLeay045\n"); 205#endif 206 } 207 else 208 { 209 RSAerr(RSA_F_RSA_VERIFY, 210 RSA_R_ALGORITHM_MISMATCH); 211 goto err; 212 } 213 } 214 if ( ((unsigned int)sig->digest->length != m_len) || 215 (memcmp(m,sig->digest->data,m_len) != 0)) 216 { 217 RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE); 218 } 219 else 220 ret=1; 221 } 222err: 223 if (sig != NULL) X509_SIG_free(sig); 224 OPENSSL_cleanse(s,(unsigned int)siglen); 225 OPENSSL_free(s); 226 return(ret); 227 } 228 229