sl@0: /* crypto/rsa/rsa_sign.c */
sl@0: /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
sl@0:  * All rights reserved.
sl@0:  *
sl@0:  * This package is an SSL implementation written
sl@0:  * by Eric Young (eay@cryptsoft.com).
sl@0:  * The implementation was written so as to conform with Netscapes SSL.
sl@0:  * 
sl@0:  * This library is free for commercial and non-commercial use as long as
sl@0:  * the following conditions are aheared to.  The following conditions
sl@0:  * apply to all code found in this distribution, be it the RC4, RSA,
sl@0:  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
sl@0:  * included with this distribution is covered by the same copyright terms
sl@0:  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
sl@0:  * 
sl@0:  * Copyright remains Eric Young's, and as such any Copyright notices in
sl@0:  * the code are not to be removed.
sl@0:  * If this package is used in a product, Eric Young should be given attribution
sl@0:  * as the author of the parts of the library used.
sl@0:  * This can be in the form of a textual message at program startup or
sl@0:  * in documentation (online or textual) provided with the package.
sl@0:  * 
sl@0:  * Redistribution and use in source and binary forms, with or without
sl@0:  * modification, are permitted provided that the following conditions
sl@0:  * are met:
sl@0:  * 1. Redistributions of source code must retain the copyright
sl@0:  *    notice, this list of conditions and the following disclaimer.
sl@0:  * 2. Redistributions in binary form must reproduce the above copyright
sl@0:  *    notice, this list of conditions and the following disclaimer in the
sl@0:  *    documentation and/or other materials provided with the distribution.
sl@0:  * 3. All advertising materials mentioning features or use of this software
sl@0:  *    must display the following acknowledgement:
sl@0:  *    "This product includes cryptographic software written by
sl@0:  *     Eric Young (eay@cryptsoft.com)"
sl@0:  *    The word 'cryptographic' can be left out if the rouines from the library
sl@0:  *    being used are not cryptographic related :-).
sl@0:  * 4. If you include any Windows specific code (or a derivative thereof) from 
sl@0:  *    the apps directory (application code) you must include an acknowledgement:
sl@0:  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
sl@0:  * 
sl@0:  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
sl@0:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
sl@0:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
sl@0:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
sl@0:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
sl@0:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
sl@0:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
sl@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
sl@0:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
sl@0:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
sl@0:  * SUCH DAMAGE.
sl@0:  * 
sl@0:  * The licence and distribution terms for any publically available version or
sl@0:  * derivative of this code cannot be changed.  i.e. this code cannot simply be
sl@0:  * copied and put under another distribution licence
sl@0:  * [including the GNU Public Licence.]
sl@0:  */
sl@0: 
sl@0: #include <stdio.h>
sl@0: #include "cryptlib.h"
sl@0: #include <openssl/bn.h>
sl@0: #include <openssl/rsa.h>
sl@0: #include <openssl/objects.h>
sl@0: #include <openssl/x509.h>
sl@0: 
sl@0: /* Size of an SSL signature: MD5+SHA1 */
sl@0: #define SSL_SIG_LENGTH	36
sl@0: 
sl@0: EXPORT_C int RSA_sign(int type, const unsigned char *m, unsigned int m_len,
sl@0: 	     unsigned char *sigret, unsigned int *siglen, RSA *rsa)
sl@0: 	{
sl@0: 	X509_SIG sig;
sl@0: 	ASN1_TYPE parameter;
sl@0: 	int i,j,ret=1;
sl@0: 	unsigned char *p, *tmps = NULL;
sl@0: 	const unsigned char *s = NULL;
sl@0: 	X509_ALGOR algor;
sl@0: 	ASN1_OCTET_STRING digest;
sl@0: 	if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_sign)
sl@0: 		{
sl@0: 		return rsa->meth->rsa_sign(type, m, m_len,
sl@0: 			sigret, siglen, rsa);
sl@0: 		}
sl@0: 	/* Special case: SSL signature, just check the length */
sl@0: 	if(type == NID_md5_sha1) {
sl@0: 		if(m_len != SSL_SIG_LENGTH) {
sl@0: 			RSAerr(RSA_F_RSA_SIGN,RSA_R_INVALID_MESSAGE_LENGTH);
sl@0: 			return(0);
sl@0: 		}
sl@0: 		i = SSL_SIG_LENGTH;
sl@0: 		s = m;
sl@0: 	} else {
sl@0: 		sig.algor= &algor;
sl@0: 		sig.algor->algorithm=OBJ_nid2obj(type);
sl@0: 		if (sig.algor->algorithm == NULL)
sl@0: 			{
sl@0: 			RSAerr(RSA_F_RSA_SIGN,RSA_R_UNKNOWN_ALGORITHM_TYPE);
sl@0: 			return(0);
sl@0: 			}
sl@0: 		if (sig.algor->algorithm->length == 0)
sl@0: 			{
sl@0: 			RSAerr(RSA_F_RSA_SIGN,RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
sl@0: 			return(0);
sl@0: 			}
sl@0: 		parameter.type=V_ASN1_NULL;
sl@0: 		parameter.value.ptr=NULL;
sl@0: 		sig.algor->parameter= &parameter;
sl@0: 
sl@0: 		sig.digest= &digest;
sl@0: 		sig.digest->data=(unsigned char *)m; /* TMP UGLY CAST */
sl@0: 		sig.digest->length=m_len;
sl@0: 
sl@0: 		i=i2d_X509_SIG(&sig,NULL);
sl@0: 	}
sl@0: 	j=RSA_size(rsa);
sl@0: 	if (i > (j-RSA_PKCS1_PADDING_SIZE))
sl@0: 		{
sl@0: 		RSAerr(RSA_F_RSA_SIGN,RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
sl@0: 		return(0);
sl@0: 		}
sl@0: 	if(type != NID_md5_sha1) {
sl@0: 		tmps=(unsigned char *)OPENSSL_malloc((unsigned int)j+1);
sl@0: 		if (tmps == NULL)
sl@0: 			{
sl@0: 			RSAerr(RSA_F_RSA_SIGN,ERR_R_MALLOC_FAILURE);
sl@0: 			return(0);
sl@0: 			}
sl@0: 		p=tmps;
sl@0: 		i2d_X509_SIG(&sig,&p);
sl@0: 		s=tmps;
sl@0: 	}
sl@0: 	i=RSA_private_encrypt(i,s,sigret,rsa,RSA_PKCS1_PADDING);
sl@0: 	if (i <= 0)
sl@0: 		ret=0;
sl@0: 	else
sl@0: 		*siglen=i;
sl@0: 
sl@0: 	if(type != NID_md5_sha1) {
sl@0: 		OPENSSL_cleanse(tmps,(unsigned int)j+1);
sl@0: 		OPENSSL_free(tmps);
sl@0: 	}
sl@0: 	return(ret);
sl@0: 	}
sl@0: 
sl@0: EXPORT_C int RSA_verify(int dtype, const unsigned char *m, unsigned int m_len,
sl@0: 	     unsigned char *sigbuf, unsigned int siglen, RSA *rsa)
sl@0: 	{
sl@0: 	int i,ret=0,sigtype;
sl@0: 	unsigned char *s;
sl@0: 	X509_SIG *sig=NULL;
sl@0: 
sl@0: 	if (siglen != (unsigned int)RSA_size(rsa))
sl@0: 		{
sl@0: 		RSAerr(RSA_F_RSA_VERIFY,RSA_R_WRONG_SIGNATURE_LENGTH);
sl@0: 		return(0);
sl@0: 		}
sl@0: 
sl@0: 	if((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_verify)
sl@0: 		{
sl@0: 		return rsa->meth->rsa_verify(dtype, m, m_len,
sl@0: 			sigbuf, siglen, rsa);
sl@0: 		}
sl@0: 
sl@0: 	s=(unsigned char *)OPENSSL_malloc((unsigned int)siglen);
sl@0: 	if (s == NULL)
sl@0: 		{
sl@0: 		RSAerr(RSA_F_RSA_VERIFY,ERR_R_MALLOC_FAILURE);
sl@0: 		goto err;
sl@0: 		}
sl@0: 	if((dtype == NID_md5_sha1) && (m_len != SSL_SIG_LENGTH) ) {
sl@0: 			RSAerr(RSA_F_RSA_VERIFY,RSA_R_INVALID_MESSAGE_LENGTH);
sl@0: 			goto err;
sl@0: 	}
sl@0: 	i=RSA_public_decrypt((int)siglen,sigbuf,s,rsa,RSA_PKCS1_PADDING);
sl@0: 
sl@0: 	if (i <= 0) goto err;
sl@0: 
sl@0: 	/* Special case: SSL signature */
sl@0: 	if(dtype == NID_md5_sha1) {
sl@0: 		if((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH))
sl@0: 				RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
sl@0: 		else ret = 1;
sl@0: 	} else {
sl@0: 		const unsigned char *p=s;
sl@0: 		sig=d2i_X509_SIG(NULL,&p,(long)i);
sl@0: 
sl@0: 		if (sig == NULL) goto err;
sl@0: 		
sl@0: 		/* Excess data can be used to create forgeries */
sl@0: 		if(p != s+i)
sl@0: 			{
sl@0: 			RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
sl@0: 			goto err;
sl@0: 			}
sl@0: 
sl@0: 		/* Parameters to the signature algorithm can also be used to
sl@0: 		   create forgeries */
sl@0: 		if(sig->algor->parameter
sl@0: 		   && ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL)
sl@0: 			{
sl@0: 			RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
sl@0: 			goto err;
sl@0: 			}
sl@0: 		sigtype=OBJ_obj2nid(sig->algor->algorithm);
sl@0: 
sl@0: 
sl@0: 	#ifdef RSA_DEBUG
sl@0: 		/* put a backward compatibility flag in EAY */
sl@0: 		fprintf(stderr,"in(%s) expect(%s)\n",OBJ_nid2ln(sigtype),
sl@0: 			OBJ_nid2ln(dtype));
sl@0: 	#endif
sl@0: 		if (sigtype != dtype)
sl@0: 			{
sl@0: 			if (((dtype == NID_md5) &&
sl@0: 				(sigtype == NID_md5WithRSAEncryption)) ||
sl@0: 				((dtype == NID_md2) &&
sl@0: 				(sigtype == NID_md2WithRSAEncryption)))
sl@0: 				{
sl@0: 				/* ok, we will let it through */
sl@0: #if !defined(OPENSSL_NO_STDIO) && !defined(OPENSSL_SYS_WIN16)
sl@0: 				fprintf(stderr,"signature has problems, re-make with post SSLeay045\n");
sl@0: #endif
sl@0: 				}
sl@0: 			else
sl@0: 				{
sl@0: 				RSAerr(RSA_F_RSA_VERIFY,
sl@0: 						RSA_R_ALGORITHM_MISMATCH);
sl@0: 				goto err;
sl@0: 				}
sl@0: 			}
sl@0: 		if (	((unsigned int)sig->digest->length != m_len) ||
sl@0: 			(memcmp(m,sig->digest->data,m_len) != 0))
sl@0: 			{
sl@0: 			RSAerr(RSA_F_RSA_VERIFY,RSA_R_BAD_SIGNATURE);
sl@0: 			}
sl@0: 		else
sl@0: 			ret=1;
sl@0: 	}
sl@0: err:
sl@0: 	if (sig != NULL) X509_SIG_free(sig);
sl@0: 	if (s != NULL)
sl@0: 		{
sl@0: 		OPENSSL_cleanse(s,(unsigned int)siglen);
sl@0: 		OPENSSL_free(s);
sl@0: 		}
sl@0: 	return(ret);
sl@0: 	}
sl@0: