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    /* $OpenBSD: rsa_sign.c,v 1.29 2017/05/02 03:59:45 deraadt Exp $ */  | 
    
    
    2  | 
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    /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)  | 
    
    
    3  | 
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     * All rights reserved.  | 
    
    
    4  | 
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     *  | 
    
    
    5  | 
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     * This package is an SSL implementation written  | 
    
    
    6  | 
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     * by Eric Young (eay@cryptsoft.com).  | 
    
    
    7  | 
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     * The implementation was written so as to conform with Netscapes SSL.  | 
    
    
    8  | 
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     *  | 
    
    
    9  | 
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     * This library is free for commercial and non-commercial use as long as  | 
    
    
    10  | 
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     * the following conditions are aheared to.  The following conditions  | 
    
    
    11  | 
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     * apply to all code found in this distribution, be it the RC4, RSA,  | 
    
    
    12  | 
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     * lhash, DES, etc., code; not just the SSL code.  The SSL documentation  | 
    
    
    13  | 
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     * included with this distribution is covered by the same copyright terms  | 
    
    
    14  | 
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     * except that the holder is Tim Hudson (tjh@cryptsoft.com).  | 
    
    
    15  | 
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     *  | 
    
    
    16  | 
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     * Copyright remains Eric Young's, and as such any Copyright notices in  | 
    
    
    17  | 
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     * the code are not to be removed.  | 
    
    
    18  | 
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     * If this package is used in a product, Eric Young should be given attribution  | 
    
    
    19  | 
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     * as the author of the parts of the library used.  | 
    
    
    20  | 
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     * This can be in the form of a textual message at program startup or  | 
    
    
    21  | 
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     * in documentation (online or textual) provided with the package.  | 
    
    
    22  | 
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     *  | 
    
    
    23  | 
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     * Redistribution and use in source and binary forms, with or without  | 
    
    
    24  | 
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     * modification, are permitted provided that the following conditions  | 
    
    
    25  | 
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     * are met:  | 
    
    
    26  | 
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     * 1. Redistributions of source code must retain the copyright  | 
    
    
    27  | 
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     *    notice, this list of conditions and the following disclaimer.  | 
    
    
    28  | 
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     * 2. Redistributions in binary form must reproduce the above copyright  | 
    
    
    29  | 
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     *    notice, this list of conditions and the following disclaimer in the  | 
    
    
    30  | 
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     *    documentation and/or other materials provided with the distribution.  | 
    
    
    31  | 
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     * 3. All advertising materials mentioning features or use of this software  | 
    
    
    32  | 
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     *    must display the following acknowledgement:  | 
    
    
    33  | 
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     *    "This product includes cryptographic software written by  | 
    
    
    34  | 
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     *     Eric Young (eay@cryptsoft.com)"  | 
    
    
    35  | 
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     *    The word 'cryptographic' can be left out if the rouines from the library  | 
    
    
    36  | 
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     *    being used are not cryptographic related :-).  | 
    
    
    37  | 
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     * 4. If you include any Windows specific code (or a derivative thereof) from  | 
    
    
    38  | 
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     *    the apps directory (application code) you must include an acknowledgement:  | 
    
    
    39  | 
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     *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"  | 
    
    
    40  | 
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     *  | 
    
    
    41  | 
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     * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND  | 
    
    
    42  | 
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     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE  | 
    
    
    43  | 
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     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE  | 
    
    
    44  | 
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     * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE  | 
    
    
    45  | 
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     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL  | 
    
    
    46  | 
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     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS  | 
    
    
    47  | 
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     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)  | 
    
    
    48  | 
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     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT  | 
    
    
    49  | 
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     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY  | 
    
    
    50  | 
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     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF  | 
    
    
    51  | 
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     * SUCH DAMAGE.  | 
    
    
    52  | 
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     *  | 
    
    
    53  | 
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     * The licence and distribution terms for any publically available version or  | 
    
    
    54  | 
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     * derivative of this code cannot be changed.  i.e. this code cannot simply be  | 
    
    
    55  | 
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     * copied and put under another distribution licence  | 
    
    
    56  | 
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     * [including the GNU Public Licence.]  | 
    
    
    57  | 
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     */  | 
    
    
    58  | 
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    59  | 
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    #include <stdio.h>  | 
    
    
    60  | 
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    #include <string.h>  | 
    
    
    61  | 
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    62  | 
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    #include <openssl/bn.h>  | 
    
    
    63  | 
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    #include <openssl/err.h>  | 
    
    
    64  | 
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    #include <openssl/objects.h>  | 
    
    
    65  | 
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    #include <openssl/rsa.h>  | 
    
    
    66  | 
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    #include <openssl/x509.h>  | 
    
    
    67  | 
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    68  | 
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    #include "rsa_locl.h"  | 
    
    
    69  | 
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    70  | 
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    /* Size of an SSL signature: MD5+SHA1 */  | 
    
    
    71  | 
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    #define SSL_SIG_LENGTH	36  | 
    
    
    72  | 
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    73  | 
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    int  | 
    
    
    74  | 
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    RSA_sign(int type, const unsigned char *m, unsigned int m_len,  | 
    
    
    75  | 
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        unsigned char *sigret, unsigned int *siglen, RSA *rsa)  | 
    
    
    76  | 
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    { | 
    
    
    77  | 
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    40340  | 
    	X509_SIG sig;  | 
    
    
    78  | 
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    20170  | 
    	ASN1_TYPE parameter;  | 
    
    
    79  | 
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    	int i, j, ret = 1;  | 
    
    
    80  | 
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    20170  | 
    	unsigned char *p, *tmps = NULL;  | 
    
    
    81  | 
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    	const unsigned char *s = NULL;  | 
    
    
    82  | 
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    20170  | 
    	X509_ALGOR algor;  | 
    
    
    83  | 
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    20170  | 
    	ASN1_OCTET_STRING digest;  | 
    
    
    84  | 
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    85  | 
    ✗✓✗✗
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    20170  | 
    	if ((rsa->flags & RSA_FLAG_SIGN_VER) && rsa->meth->rsa_sign)  | 
    
    
    86  | 
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    		return rsa->meth->rsa_sign(type, m, m_len, sigret, siglen, rsa);  | 
    
    
    87  | 
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    88  | 
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    	/* Special case: SSL signature, just check the length */  | 
    
    
    89  | 
    ✓✓ | 
    20170  | 
    	if (type == NID_md5_sha1) { | 
    
    
    90  | 
    ✗✓ | 
    19952  | 
    		if (m_len != SSL_SIG_LENGTH) { | 
    
    
    91  | 
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    			RSAerror(RSA_R_INVALID_MESSAGE_LENGTH);  | 
    
    
    92  | 
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    			return 0;  | 
    
    
    93  | 
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    		}  | 
    
    
    94  | 
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    		i = SSL_SIG_LENGTH;  | 
    
    
    95  | 
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    		s = m;  | 
    
    
    96  | 
     | 
    19952  | 
    	} else { | 
    
    
    97  | 
     | 
    218  | 
    		sig.algor = &algor;  | 
    
    
    98  | 
     | 
    218  | 
    		sig.algor->algorithm = OBJ_nid2obj(type);  | 
    
    
    99  | 
    ✗✓ | 
    218  | 
    		if (sig.algor->algorithm == NULL) { | 
    
    
    100  | 
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    			RSAerror(RSA_R_UNKNOWN_ALGORITHM_TYPE);  | 
    
    
    101  | 
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    			return 0;  | 
    
    
    102  | 
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    		}  | 
    
    
    103  | 
    ✗✓ | 
    218  | 
    		if (sig.algor->algorithm->length == 0) { | 
    
    
    104  | 
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    			RSAerror(RSA_R_THE_ASN1_OBJECT_IDENTIFIER_IS_NOT_KNOWN_FOR_THIS_MD);  | 
    
    
    105  | 
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    			return 0;  | 
    
    
    106  | 
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    		}  | 
    
    
    107  | 
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    218  | 
    		parameter.type = V_ASN1_NULL;  | 
    
    
    108  | 
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    218  | 
    		parameter.value.ptr = NULL;  | 
    
    
    109  | 
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    218  | 
    		sig.algor->parameter = ¶meter;  | 
    
    
    110  | 
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    111  | 
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    218  | 
    		sig.digest = &digest;  | 
    
    
    112  | 
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    218  | 
    		sig.digest->data = (unsigned char *)m; /* TMP UGLY CAST */  | 
    
    
    113  | 
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    218  | 
    		sig.digest->length = m_len;  | 
    
    
    114  | 
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    115  | 
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    218  | 
    		i = i2d_X509_SIG(&sig, NULL);  | 
    
    
    116  | 
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    	}  | 
    
    
    117  | 
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    20170  | 
    	j = RSA_size(rsa);  | 
    
    
    118  | 
    ✗✓ | 
    20170  | 
    	if (i > j - RSA_PKCS1_PADDING_SIZE) { | 
    
    
    119  | 
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    		RSAerror(RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY);  | 
    
    
    120  | 
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    		return 0;  | 
    
    
    121  | 
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    	}  | 
    
    
    122  | 
    ✓✓ | 
    20170  | 
    	if (type != NID_md5_sha1) { | 
    
    
    123  | 
     | 
    218  | 
    		tmps = malloc(j + 1);  | 
    
    
    124  | 
    ✗✓ | 
    218  | 
    		if (tmps == NULL) { | 
    
    
    125  | 
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    			RSAerror(ERR_R_MALLOC_FAILURE);  | 
    
    
    126  | 
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    			return 0;  | 
    
    
    127  | 
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    		}  | 
    
    
    128  | 
     | 
    218  | 
    		p = tmps;  | 
    
    
    129  | 
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    218  | 
    		i2d_X509_SIG(&sig, &p);  | 
    
    
    130  | 
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    		s = tmps;  | 
    
    
    131  | 
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    218  | 
    	}  | 
    
    
    132  | 
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    20170  | 
    	i = RSA_private_encrypt(i, s, sigret, rsa, RSA_PKCS1_PADDING);  | 
    
    
    133  | 
    ✗✓ | 
    20170  | 
    	if (i <= 0)  | 
    
    
    134  | 
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    		ret = 0;  | 
    
    
    135  | 
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    	else  | 
    
    
    136  | 
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    20170  | 
    		*siglen = i;  | 
    
    
    137  | 
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    138  | 
    ✓✓ | 
    20170  | 
    	if (type != NID_md5_sha1)  | 
    
    
    139  | 
     | 
    218  | 
    		freezero(tmps, (unsigned int)j + 1);  | 
    
    
    140  | 
     | 
    20170  | 
    	return (ret);  | 
    
    
    141  | 
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    20170  | 
    }  | 
    
    
    142  | 
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    143  | 
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    int  | 
    
    
    144  | 
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    int_rsa_verify(int dtype, const unsigned char *m, unsigned int m_len,  | 
    
    
    145  | 
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        unsigned char *rm, size_t *prm_len, const unsigned char *sigbuf,  | 
    
    
    146  | 
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        size_t siglen, RSA *rsa)  | 
    
    
    147  | 
     | 
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    { | 
    
    
    148  | 
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    	int i, ret = 0, sigtype;  | 
    
    
    149  | 
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    	unsigned char *s;  | 
    
    
    150  | 
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    	X509_SIG *sig = NULL;  | 
    
    
    151  | 
     | 
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    152  | 
    ✗✓ | 
    688712  | 
    	if (siglen != (unsigned int)RSA_size(rsa)) { | 
    
    
    153  | 
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    		RSAerror(RSA_R_WRONG_SIGNATURE_LENGTH);  | 
    
    
    154  | 
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    		return 0;  | 
    
    
    155  | 
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    	}  | 
    
    
    156  | 
     | 
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    157  | 
    ✗✓ | 
    344356  | 
    	if ((dtype == NID_md5_sha1) && rm) { | 
    
    
    158  | 
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    		i = RSA_public_decrypt((int)siglen, sigbuf, rm, rsa,  | 
    
    
    159  | 
     | 
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    		    RSA_PKCS1_PADDING);  | 
    
    
    160  | 
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    		if (i <= 0)  | 
    
    
    161  | 
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    			return 0;  | 
    
    
    162  | 
     | 
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    		*prm_len = i;  | 
    
    
    163  | 
     | 
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    		return 1;  | 
    
    
    164  | 
     | 
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    	}  | 
    
    
    165  | 
     | 
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    166  | 
     | 
    344356  | 
    	s = malloc(siglen);  | 
    
    
    167  | 
    ✗✓ | 
    344356  | 
    	if (s == NULL) { | 
    
    
    168  | 
     | 
     | 
    		RSAerror(ERR_R_MALLOC_FAILURE);  | 
    
    
    169  | 
     | 
     | 
    		goto err;  | 
    
    
    170  | 
     | 
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    	}  | 
    
    
    171  | 
    ✗✓ | 
    344356  | 
    	if (dtype == NID_md5_sha1 && m_len != SSL_SIG_LENGTH) { | 
    
    
    172  | 
     | 
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    		RSAerror(RSA_R_INVALID_MESSAGE_LENGTH);  | 
    
    
    173  | 
     | 
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    		goto err;  | 
    
    
    174  | 
     | 
     | 
    	}  | 
    
    
    175  | 
     | 
    344356  | 
    	i = RSA_public_decrypt((int)siglen, sigbuf, s, rsa, RSA_PKCS1_PADDING);  | 
    
    
    176  | 
     | 
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    177  | 
    ✓✗ | 
    344356  | 
    	if (i <= 0)  | 
    
    
    178  | 
     | 
     | 
    		goto err;  | 
    
    
    179  | 
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    180  | 
     | 
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    	/* Special case: SSL signature */  | 
    
    
    181  | 
    ✓✓ | 
    344356  | 
    	if (dtype == NID_md5_sha1) { | 
    
    
    182  | 
    ✓✗✗✓
  | 
    684260  | 
    		if (i != SSL_SIG_LENGTH || memcmp(s, m, SSL_SIG_LENGTH))  | 
    
    
    183  | 
     | 
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    			RSAerror(RSA_R_BAD_SIGNATURE);  | 
    
    
    184  | 
     | 
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    		else  | 
    
    
    185  | 
     | 
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    			ret = 1;  | 
    
    
    186  | 
     | 
     | 
    	} else { | 
    
    
    187  | 
     | 
    2226  | 
    		const unsigned char *p = s;  | 
    
    
    188  | 
     | 
     | 
     | 
    
    
    189  | 
     | 
    2226  | 
    		sig = d2i_X509_SIG(NULL, &p, (long)i);  | 
    
    
    190  | 
     | 
     | 
     | 
    
    
    191  | 
    ✗✓ | 
    2226  | 
    		if (sig == NULL)  | 
    
    
    192  | 
     | 
     | 
    			goto err;  | 
    
    
    193  | 
     | 
     | 
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    194  | 
     | 
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    		/* Excess data can be used to create forgeries */  | 
    
    
    195  | 
    ✗✓ | 
    2226  | 
    		if (p != s + i) { | 
    
    
    196  | 
     | 
     | 
    			RSAerror(RSA_R_BAD_SIGNATURE);  | 
    
    
    197  | 
     | 
     | 
    			goto err;  | 
    
    
    198  | 
     | 
     | 
    		}  | 
    
    
    199  | 
     | 
     | 
     | 
    
    
    200  | 
     | 
     | 
    		/* Parameters to the signature algorithm can also be used to  | 
    
    
    201  | 
     | 
     | 
    		   create forgeries */  | 
    
    
    202  | 
    ✓✗✗✓
  | 
    4452  | 
    		if (sig->algor->parameter &&  | 
    
    
    203  | 
     | 
    2226  | 
    		    ASN1_TYPE_get(sig->algor->parameter) != V_ASN1_NULL) { | 
    
    
    204  | 
     | 
     | 
    			RSAerror(RSA_R_BAD_SIGNATURE);  | 
    
    
    205  | 
     | 
     | 
    			goto err;  | 
    
    
    206  | 
     | 
     | 
    		}  | 
    
    
    207  | 
     | 
     | 
     | 
    
    
    208  | 
     | 
    2226  | 
    		sigtype = OBJ_obj2nid(sig->algor->algorithm);  | 
    
    
    209  | 
     | 
     | 
     | 
    
    
    210  | 
    ✗✓ | 
    2226  | 
    		if (sigtype != dtype) { | 
    
    
    211  | 
     | 
     | 
    			RSAerror(RSA_R_ALGORITHM_MISMATCH);  | 
    
    
    212  | 
     | 
     | 
    			goto err;  | 
    
    
    213  | 
     | 
     | 
    		}  | 
    
    
    214  | 
    ✗✓ | 
    2226  | 
    		if (rm) { | 
    
    
    215  | 
     | 
     | 
    			const EVP_MD *md;  | 
    
    
    216  | 
     | 
     | 
     | 
    
    
    217  | 
     | 
     | 
    			md = EVP_get_digestbynid(dtype);  | 
    
    
    218  | 
     | 
     | 
    			if (md && (EVP_MD_size(md) != sig->digest->length))  | 
    
    
    219  | 
     | 
     | 
    				RSAerror(RSA_R_INVALID_DIGEST_LENGTH);  | 
    
    
    220  | 
     | 
     | 
    			else { | 
    
    
    221  | 
     | 
     | 
    				memcpy(rm, sig->digest->data,  | 
    
    
    222  | 
     | 
     | 
    				    sig->digest->length);  | 
    
    
    223  | 
     | 
     | 
    				*prm_len = sig->digest->length;  | 
    
    
    224  | 
     | 
     | 
    				ret = 1;  | 
    
    
    225  | 
     | 
     | 
    			}  | 
    
    
    226  | 
    ✓✗✗✓
  | 
    4452  | 
    		} else if ((unsigned int)sig->digest->length != m_len ||  | 
    
    
    227  | 
     | 
    2226  | 
    		    memcmp(m, sig->digest->data, m_len) != 0) { | 
    
    
    228  | 
     | 
     | 
    			RSAerror(RSA_R_BAD_SIGNATURE);  | 
    
    
    229  | 
     | 
     | 
    		} else  | 
    
    
    230  | 
     | 
     | 
    			ret = 1;  | 
    
    
    231  | 
    ✗✓✓ | 
    6718  | 
    	}  | 
    
    
    232  | 
     | 
     | 
    err:  | 
    
    
    233  | 
     | 
    344356  | 
    	X509_SIG_free(sig);  | 
    
    
    234  | 
     | 
    344356  | 
    	freezero(s, (unsigned int)siglen);  | 
    
    
    235  | 
     | 
    344356  | 
    	return ret;  | 
    
    
    236  | 
     | 
    344356  | 
    }  | 
    
    
    237  | 
     | 
     | 
     | 
    
    
    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,  | 
    
    
    244  | 
     | 
     | 
    		    rsa);  | 
    
    
    245  | 
     | 
     | 
     | 
    
    
    246  | 
     | 
    344356  | 
    	return int_rsa_verify(dtype, m, m_len, NULL, NULL, sigbuf, siglen, rsa);  | 
    
    
    247  | 
     | 
    344356  | 
    }  |