GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libcrypto/rsa/rsa_sign.c Lines: 63 103 61.2 %
Date: 2017-11-07 Branches: 33 67 49.3 %

Line Branch Exec Source
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/* $OpenBSD: rsa_sign.c,v 1.29 2017/05/02 03:59:45 deraadt Exp $ */
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/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
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 * All rights reserved.
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 *
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 * This package is an SSL implementation written
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 * by Eric Young (eay@cryptsoft.com).
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 * The implementation was written so as to conform with Netscapes SSL.
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 *
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 * This library is free for commercial and non-commercial use as long as
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 * the following conditions are aheared to.  The following conditions
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 * apply to all code found in this distribution, be it the RC4, RSA,
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 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
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 * included with this distribution is covered by the same copyright terms
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 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
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 *
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 * Copyright remains Eric Young's, and as such any Copyright notices in
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 * the code are not to be removed.
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 * If this package is used in a product, Eric Young should be given attribution
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 * as the author of the parts of the library used.
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 * This can be in the form of a textual message at program startup or
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 * in documentation (online or textual) provided with the package.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. All advertising materials mentioning features or use of this software
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 *    must display the following acknowledgement:
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 *    "This product includes cryptographic software written by
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 *     Eric Young (eay@cryptsoft.com)"
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 *    The word 'cryptographic' can be left out if the rouines from the library
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 *    being used are not cryptographic related :-).
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 * 4. If you include any Windows specific code (or a derivative thereof) from
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 *    the apps directory (application code) you must include an acknowledgement:
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 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
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 *
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 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 *
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 * The licence and distribution terms for any publically available version or
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 * derivative of this code cannot be changed.  i.e. this code cannot simply be
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 * copied and put under another distribution licence
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 * [including the GNU Public Licence.]
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 */
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#include <stdio.h>
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#include <string.h>
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#include <openssl/bn.h>
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#include <openssl/err.h>
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#include <openssl/objects.h>
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#include <openssl/rsa.h>
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#include <openssl/x509.h>
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#include "rsa_locl.h"
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/* Size of an SSL signature: MD5+SHA1 */
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#define SSL_SIG_LENGTH	36
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int
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RSA_sign(int type, const unsigned char *m, unsigned int m_len,
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    unsigned char *sigret, unsigned int *siglen, RSA *rsa)
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{
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40340
	X509_SIG sig;
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20170
	ASN1_TYPE parameter;
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	int i, j, ret = 1;
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20170
	unsigned char *p, *tmps = NULL;
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	const unsigned char *s = NULL;
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20170
	X509_ALGOR algor;
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20170
	ASN1_OCTET_STRING digest;
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85

20170
	if ((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_sign)
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		return rsa->meth->rsa_sign(type, m, m_len, sigret, siglen, rsa);
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	/* Special case: SSL signature, just check the length */
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20170
	if (type == NID_md5_sha1) {
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19952
		if (m_len != SSL_SIG_LENGTH) {
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			RSAerror(RSA_R_INVALID_MESSAGE_LENGTH);
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			return 0;
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		}
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		i = SSL_SIG_LENGTH;
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		s = m;
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19952
	} else {
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218
		sig.algor = &algor;
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		sig.algor->algorithm = OBJ_nid2obj(type);
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218
		if (sig.algor->algorithm == NULL) {
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			RSAerror(RSA_R_UNKNOWN_ALGORITHM_TYPE);
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			return 0;
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		}
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		if (sig.algor->algorithm->length == 0) {
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			RSAerror(RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);
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			return 0;
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		}
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218
		parameter.type = V_ASN1_NULL;
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218
		parameter.value.ptr = NULL;
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218
		sig.algor->parameter = &parameter;
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111
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		sig.digest = &digest;
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		sig.digest->data = (unsigned char *)m; /* TMP UGLY CAST */
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218
		sig.digest->length = m_len;
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115
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		i = i2d_X509_SIG(&sig, NULL);
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	}
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20170
	j = RSA_size(rsa);
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20170
	if (i > j - RSA_PKCS1_PADDING_SIZE) {
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		RSAerror(RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);
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		return 0;
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	}
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20170
	if (type != NID_md5_sha1) {
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		tmps = malloc(j + 1);
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218
		if (tmps == NULL) {
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			RSAerror(ERR_R_MALLOC_FAILURE);
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			return 0;
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		}
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		p = tmps;
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218
		i2d_X509_SIG(&sig, &p);
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		s = tmps;
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218
	}
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20170
	i = RSA_private_encrypt(i, s, sigret, rsa, RSA_PKCS1_PADDING);
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20170
	if (i <= 0)
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		ret = 0;
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	else
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20170
		*siglen = i;
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138
20170
	if (type != NID_md5_sha1)
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218
		freezero(tmps, (unsigned int)j + 1);
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20170
	return (ret);
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20170
}
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143
int
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int_rsa_verify(int dtype, const unsigned char *m, unsigned int m_len,
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    unsigned char *rm, size_t *prm_len, const unsigned char *sigbuf,
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    size_t siglen, RSA *rsa)
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{
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	int i, ret = 0, sigtype;
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	unsigned char *s;
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	X509_SIG *sig = NULL;
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152
688712
	if (siglen != (unsigned int)RSA_size(rsa)) {
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		RSAerror(RSA_R_WRONG_SIGNATURE_LENGTH);
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		return 0;
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	}
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344356
	if ((dtype == NID_md5_sha1) && rm) {
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		i = RSA_public_decrypt((int)siglen, sigbuf, rm, rsa,
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		    RSA_PKCS1_PADDING);
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		if (i <= 0)
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			return 0;
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		*prm_len = i;
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		return 1;
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	}
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166
344356
	s = malloc(siglen);
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344356
	if (s == NULL) {
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		RSAerror(ERR_R_MALLOC_FAILURE);
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		goto err;
170
	}
171
344356
	if (dtype == NID_md5_sha1 && m_len != SSL_SIG_LENGTH) {
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		RSAerror(RSA_R_INVALID_MESSAGE_LENGTH);
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		goto err;
174
	}
175
344356
	i = RSA_public_decrypt((int)siglen, sigbuf, s, rsa, RSA_PKCS1_PADDING);
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177
344356
	if (i <= 0)
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		goto err;
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180
	/* Special case: SSL signature */
181
344356
	if (dtype == NID_md5_sha1) {
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684260
		if (i != SSL_SIG_LENGTH || memcmp(s, m, SSL_SIG_LENGTH))
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			RSAerror(RSA_R_BAD_SIGNATURE);
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		else
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			ret = 1;
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	} else {
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2226
		const unsigned char *p = s;
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189
2226
		sig = d2i_X509_SIG(NULL, &p, (long)i);
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191
2226
		if (sig == NULL)
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			goto err;
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194
		/* Excess data can be used to create forgeries */
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2226
		if (p != s + i) {
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			RSAerror(RSA_R_BAD_SIGNATURE);
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			goto err;
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		}
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200
		/* Parameters to the signature algorithm can also be used to
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		   create forgeries */
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4452
		if (sig->algor->parameter &&
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2226
		    ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL) {
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			RSAerror(RSA_R_BAD_SIGNATURE);
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			goto err;
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		}
207
208
2226
		sigtype = OBJ_obj2nid(sig->algor->algorithm);
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210
2226
		if (sigtype != dtype) {
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			RSAerror(RSA_R_ALGORITHM_MISMATCH);
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			goto err;
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		}
214
2226
		if (rm) {
215
			const EVP_MD *md;
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217
			md = EVP_get_digestbynid(dtype);
218
			if (md && (EVP_MD_size(md) != sig->digest->length))
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				RSAerror(RSA_R_INVALID_DIGEST_LENGTH);
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			else {
221
				memcpy(rm, sig->digest->data,
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				    sig->digest->length);
223
				*prm_len = sig->digest->length;
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				ret = 1;
225
			}
226

4452
		} else if ((unsigned int)sig->digest->length != m_len ||
227
2226
		    memcmp(m, sig->digest->data, m_len) != 0) {
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			RSAerror(RSA_R_BAD_SIGNATURE);
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		} else
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			ret = 1;
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6718
	}
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err:
233
344356
	X509_SIG_free(sig);
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344356
	freezero(s, (unsigned int)siglen);
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344356
	return ret;
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344356
}
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238
int
239
RSA_verify(int dtype, const unsigned char *m, unsigned int m_len,
240
    const unsigned char *sigbuf, unsigned int siglen, RSA *rsa)
241
{
242

688712
	if ((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_verify)
243
		return rsa->meth->rsa_verify(dtype, m, m_len, sigbuf, siglen,
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		    rsa);
245
246
344356
	return int_rsa_verify(dtype, m, m_len, NULL, NULL, sigbuf, siglen, rsa);
247
344356
}