crypto/rsa/rsa_sign.c

   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
  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)
  81               return ENGINE_get_RSA(rsa->engine)->rsa_sign(type,
  82                         m, m_len, sigret, siglen, rsa);
  83         /* Special case: SSL signature, just check the length */
  84         if(type == NID_md5_sha1) {
  85                 if(m_len != SSL_SIG_LENGTH) {
  86                         RSAerr(RSA_F_RSA_SIGN,RSA_R_INVALID_MESSAGE_LENGTH);
  87                         return(0);
  88                 }
  89                 i = SSL_SIG_LENGTH;
  90                 s = m;
  91         } else {
  92                 sig.algor= &algor;
  93                 sig.algor->algorithm=OBJ_nid2obj(type);
  94                 if (sig.algor->algorithm == NULL)
  95                         {
  96                         RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE);
  97                         return(0);
  98                         }
  99                 if (sig.algor->algorithm->length == 0)
 100                         {
 101                         RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
 102                         return(0);
 103                         }
 104                 parameter.type=V_ASN1_NULL;
 105                 parameter.value.ptr=NULL;
 106                 sig.algor->parameter= &parameter;
 107
 108                 sig.digest= &digest;
 109                 sig.digest->data=(unsigned char *)m; /* TMP UGLY CAST */
 110                 sig.digest->length=m_len;
 111
 112                 i=i2d_X509_SIG(&sig,NULL);
 113         }
 114         j=RSA_size(rsa);
 115         if ((i-RSA_PKCS1_PADDING) > j)
 116                 {
 117                 RSAerr(RSA_F_RSA_SIGN,RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
 118                 return(0);
 119                 }
 120         if(type != NID_md5_sha1) {
 121                 tmps=(unsigned char *)OPENSSL_malloc((unsigned int)j+1);
 122                 if (tmps == NULL)
 123                         {
 124                         RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE);
 125                         return(0);
 126                         }
 127                 p=tmps;
 128                 i2d_X509_SIG(&sig,&p);
 129                 s=tmps;
 130         }
 131         i=RSA_private_encrypt(i,s,sigret,rsa,RSA_PKCS1_PADDING);
 132         if (i <= 0)
 133                 ret=0;
 134         else
 135                 *siglen=i;
 136
 137         if(type != NID_md5_sha1) {
 138                 memset(tmps,0,(unsigned int)j+1);
 139                 OPENSSL_free(tmps);
 140         }
 141         return(ret);
 142         }
 143
 144 int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len,
 145              unsigned char *sigbuf, unsigned int siglen, RSA *rsa)
 146         {
 147         int i,ret=0,sigtype;
 148         unsigned char *p,*s;
 149         X509_SIG *sig=NULL;
 150
 151         if (siglen != (unsigned int)RSA_size(rsa))
 152                 {
 153                 RSAerr(RSA_F_RSA_VERIFY,RSA_R_WRONG_SIGNATURE_LENGTH);
 154                 return(0);
 155                 }
 156
 157         if(rsa->flags & RSA_FLAG_SIGN_VER)
 158             return ENGINE_get_RSA(rsa->engine)->rsa_verify(dtype,
 159                         m, m_len, sigbuf, siglen, rsa);
 160
 161         s=(unsigned char *)OPENSSL_malloc((unsigned int)siglen);
 162         if (s == NULL)
 163                 {
 164                 RSAerr(RSA_F_RSA_VERIFY,ERR_R_MALLOC_FAILURE);
 165                 goto err;
 166                 }
 167         if((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH) ) {
 168                         RSAerr(RSA_F_RSA_VERIFY,RSA_R_INVALID_MESSAGE_LENGTH);
 169                         return(0);
 170         }
 171         i=RSA_public_decrypt((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING);
 172
 173         if (i <= 0) goto err;
 174
 175         /* Special case: SSL signature */
 176         if(dtype == NID_md5_sha1) {
 177                 if((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH))
 178                                 RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
 179                 else ret = 1;
 180         } else {
 181                 p=s;
 182                 sig=d2i_X509_SIG(NULL,&p,(long)i);
 183
 184                 if (sig == NULL) goto err;
 185                 sigtype=OBJ_obj2nid(sig->algor->algorithm);
 186
 187
 188         #ifdef RSA_DEBUG
 189                 /* put a backward compatibility flag in EAY */
 190                 fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype),
 191                         OBJ_nid2ln(dtype));
 192         #endif
 193                 if (sigtype != dtype)
 194                         {
 195                         if (((dtype == NID_md5) &&
 196                                 (sigtype == NID_md5WithRSAEncryption)) ||
 197                                 ((dtype == NID_md2) &&
 198                                 (sigtype == NID_md2WithRSAEncryption)))
 199                                 {
 200                                 /* ok, we will let it through */
 201 #if !defined(OPENSSL_NO_STDIO) && !defined(OPENSSL_SYS_WIN16)
 202                                 fprintf(stderr,"signature has problems, re-make with post SSLeay045\n");
 203 #endif
 204                                 }
 205                         else
 206                                 {
 207                                 RSAerr(RSA_F_RSA_VERIFY,
 208                                                 RSA_R_ALGORITHM_MISMATCH);
 209                                 goto err;
 210                                 }
 211                         }
 212                 if (    ((unsigned int)sig->digest->length != m_len) ||
 213                         (memcmp(m,sig->digest->data,m_len) != 0))
 214                         {
 215                         RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
 216                         }
 217                 else
 218                         ret=1;
 219         }
 220 err:
 221         if (sig != NULL) X509_SIG_free(sig);
 222         memset(s,0,(unsigned int)siglen);
 223         OPENSSL_free(s);
 224         return(ret);
 225         }
 226