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    /* $OpenBSD: rsa_gen.c,v 1.22 2017/01/29 17:49:23 beck 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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    60  | 
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    /* NB: these functions have been "upgraded", the deprecated versions (which are  | 
    
    
    61  | 
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     * compatibility wrappers using these functions) are in rsa_depr.c.  | 
    
    
    62  | 
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     * - Geoff  | 
    
    
    63  | 
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     */  | 
    
    
    64  | 
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    65  | 
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    #include <stdio.h>  | 
    
    
    66  | 
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    #include <time.h>  | 
    
    
    67  | 
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    68  | 
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    #include <openssl/bn.h>  | 
    
    
    69  | 
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    #include <openssl/err.h>  | 
    
    
    70  | 
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    #include <openssl/rsa.h>  | 
    
    
    71  | 
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    72  | 
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    #include "bn_lcl.h"  | 
    
    
    73  | 
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    74  | 
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    static int rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb);  | 
    
    
    75  | 
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    76  | 
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    /*  | 
    
    
    77  | 
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     * NB: this wrapper would normally be placed in rsa_lib.c and the static  | 
    
    
    78  | 
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     * implementation would probably be in rsa_eay.c. Nonetheless, is kept here so  | 
    
    
    79  | 
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     * that we don't introduce a new linker dependency. Eg. any application that  | 
    
    
    80  | 
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     * wasn't previously linking object code related to key-generation won't have to  | 
    
    
    81  | 
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     * now just because key-generation is part of RSA_METHOD.  | 
    
    
    82  | 
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     */  | 
    
    
    83  | 
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    int  | 
    
    
    84  | 
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    RSA_generate_key_ex(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)  | 
    
    
    85  | 
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    { | 
    
    
    86  | 
    ✗✓ | 
    80  | 
    	if (rsa->meth->rsa_keygen)  | 
    
    
    87  | 
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    		return rsa->meth->rsa_keygen(rsa, bits, e_value, cb);  | 
    
    
    88  | 
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    40  | 
    	return rsa_builtin_keygen(rsa, bits, e_value, cb);  | 
    
    
    89  | 
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    40  | 
    }  | 
    
    
    90  | 
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    91  | 
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    static int  | 
    
    
    92  | 
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    rsa_builtin_keygen(RSA *rsa, int bits, BIGNUM *e_value, BN_GENCB *cb)  | 
    
    
    93  | 
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    { | 
    
    
    94  | 
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    	BIGNUM *r0 = NULL, *r1 = NULL, *r2 = NULL, *r3 = NULL, *tmp;  | 
    
    
    95  | 
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    80  | 
    	BIGNUM pr0, d, p;  | 
    
    
    96  | 
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    	int bitsp, bitsq, ok = -1, n = 0;  | 
    
    
    97  | 
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    	BN_CTX *ctx = NULL;  | 
    
    
    98  | 
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    99  | 
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    40  | 
    	ctx = BN_CTX_new();  | 
    
    
    100  | 
    ✓✗ | 
    40  | 
    	if (ctx == NULL)  | 
    
    
    101  | 
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    		goto err;  | 
    
    
    102  | 
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    40  | 
    	BN_CTX_start(ctx);  | 
    
    
    103  | 
    ✓✗ | 
    40  | 
    	if ((r0 = BN_CTX_get(ctx)) == NULL)  | 
    
    
    104  | 
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    		goto err;  | 
    
    
    105  | 
    ✓✗ | 
    40  | 
    	if ((r1 = BN_CTX_get(ctx)) == NULL)  | 
    
    
    106  | 
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    		goto err;  | 
    
    
    107  | 
    ✓✗ | 
    40  | 
    	if ((r2 = BN_CTX_get(ctx)) == NULL)  | 
    
    
    108  | 
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    		goto err;  | 
    
    
    109  | 
    ✓✗ | 
    40  | 
    	if ((r3 = BN_CTX_get(ctx)) == NULL)  | 
    
    
    110  | 
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    		goto err;  | 
    
    
    111  | 
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    112  | 
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    40  | 
    	bitsp = (bits + 1) / 2;  | 
    
    
    113  | 
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    40  | 
    	bitsq = bits - bitsp;  | 
    
    
    114  | 
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    115  | 
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    	/* We need the RSA components non-NULL */  | 
    
    
    116  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->n && ((rsa->n = BN_new()) == NULL))  | 
    
    
    117  | 
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    		goto err;  | 
    
    
    118  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->d && ((rsa->d = BN_new()) == NULL))  | 
    
    
    119  | 
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    		goto err;  | 
    
    
    120  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->e && ((rsa->e = BN_new()) == NULL))  | 
    
    
    121  | 
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    		goto err;  | 
    
    
    122  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->p && ((rsa->p = BN_new()) == NULL))  | 
    
    
    123  | 
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    		goto err;  | 
    
    
    124  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->q && ((rsa->q = BN_new()) == NULL))  | 
    
    
    125  | 
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    		goto err;  | 
    
    
    126  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->dmp1 && ((rsa->dmp1 = BN_new()) == NULL))  | 
    
    
    127  | 
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    		goto err;  | 
    
    
    128  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->dmq1 && ((rsa->dmq1 = BN_new()) == NULL))  | 
    
    
    129  | 
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    		goto err;  | 
    
    
    130  | 
    ✓✗✓✗
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    80  | 
    	if (!rsa->iqmp && ((rsa->iqmp = BN_new()) == NULL))  | 
    
    
    131  | 
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    		goto err;  | 
    
    
    132  | 
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    133  | 
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    40  | 
    	BN_copy(rsa->e, e_value);  | 
    
    
    134  | 
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    135  | 
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    	/* generate p and q */  | 
    
    
    136  | 
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    40  | 
    	for (;;) { | 
    
    
    137  | 
    ✓✗ | 
    40  | 
    		if (!BN_generate_prime_ex(rsa->p, bitsp, 0, NULL, NULL, cb))  | 
    
    
    138  | 
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    			goto err;  | 
    
    
    139  | 
    ✓✗ | 
    40  | 
    		if (!BN_sub(r2, rsa->p, BN_value_one()))  | 
    
    
    140  | 
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    			goto err;  | 
    
    
    141  | 
    ✓✗ | 
    40  | 
    		if (!BN_gcd_ct(r1, r2, rsa->e, ctx))  | 
    
    
    142  | 
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    			goto err;  | 
    
    
    143  | 
    ✓✗✓✗ ✗✓ | 
    120  | 
    		if (BN_is_one(r1))  | 
    
    
    144  | 
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    			break;  | 
    
    
    145  | 
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    		if (!BN_GENCB_call(cb, 2, n++))  | 
    
    
    146  | 
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    			goto err;  | 
    
    
    147  | 
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    	}  | 
    
    
    148  | 
    ✓✗ | 
    40  | 
    	if (!BN_GENCB_call(cb, 3, 0))  | 
    
    
    149  | 
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    		goto err;  | 
    
    
    150  | 
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    	for (;;) { | 
    
    
    151  | 
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    		/*  | 
    
    
    152  | 
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    		 * When generating ridiculously small keys, we can get stuck  | 
    
    
    153  | 
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    		 * continually regenerating the same prime values. Check for  | 
    
    
    154  | 
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    		 * this and bail if it happens 3 times.  | 
    
    
    155  | 
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    		 */  | 
    
    
    156  | 
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    		unsigned int degenerate = 0;  | 
    
    
    157  | 
     | 
    40  | 
    		do { | 
    
    
    158  | 
    ✗✓ | 
    40  | 
    			if (!BN_generate_prime_ex(rsa->q, bitsq, 0, NULL, NULL,  | 
    
    
    159  | 
     | 
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    			    cb))  | 
    
    
    160  | 
     | 
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    				goto err;  | 
    
    
    161  | 
    ✗✓✗✗
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    40  | 
    		} while (BN_cmp(rsa->p, rsa->q) == 0 &&  | 
    
    
    162  | 
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    		    ++degenerate < 3);  | 
    
    
    163  | 
    ✗✓ | 
    40  | 
    		if (degenerate == 3) { | 
    
    
    164  | 
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    			ok = 0; /* we set our own err */  | 
    
    
    165  | 
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    			RSAerror(RSA_R_KEY_SIZE_TOO_SMALL);  | 
    
    
    166  | 
     | 
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    			goto err;  | 
    
    
    167  | 
     | 
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    		}  | 
    
    
    168  | 
    ✗✓ | 
    40  | 
    		if (!BN_sub(r2, rsa->q, BN_value_one()))  | 
    
    
    169  | 
     | 
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    			goto err;  | 
    
    
    170  | 
    ✗✓ | 
    40  | 
    		if (!BN_gcd_ct(r1, r2, rsa->e, ctx))  | 
    
    
    171  | 
     | 
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    			goto err;  | 
    
    
    172  | 
    ✓✗✓✗ ✓✗ | 
    120  | 
    		if (BN_is_one(r1))  | 
    
    
    173  | 
     | 
    40  | 
    			break;  | 
    
    
    174  | 
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    		if (!BN_GENCB_call(cb, 2, n++))  | 
    
    
    175  | 
     | 
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    			goto err;  | 
    
    
    176  | 
     | 
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    	}  | 
    
    
    177  | 
    ✓✗ | 
    40  | 
    	if (!BN_GENCB_call(cb, 3, 1))  | 
    
    
    178  | 
     | 
     | 
    		goto err;  | 
    
    
    179  | 
    ✓✓ | 
    40  | 
    	if (BN_cmp(rsa->p, rsa->q) < 0) { | 
    
    
    180  | 
     | 
    16  | 
    		tmp = rsa->p;  | 
    
    
    181  | 
     | 
    16  | 
    		rsa->p = rsa->q;  | 
    
    
    182  | 
     | 
    16  | 
    		rsa->q = tmp;  | 
    
    
    183  | 
     | 
    16  | 
    	}  | 
    
    
    184  | 
     | 
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    185  | 
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    	/* calculate n */  | 
    
    
    186  | 
    ✓✗ | 
    40  | 
    	if (!BN_mul(rsa->n, rsa->p, rsa->q, ctx))  | 
    
    
    187  | 
     | 
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    		goto err;  | 
    
    
    188  | 
     | 
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     | 
    
    
    189  | 
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    	/* calculate d */  | 
    
    
    190  | 
    ✓✗ | 
    40  | 
    	if (!BN_sub(r1, rsa->p, BN_value_one()))	/* p-1 */  | 
    
    
    191  | 
     | 
     | 
    		goto err;  | 
    
    
    192  | 
    ✓✗ | 
    40  | 
    	if (!BN_sub(r2, rsa->q, BN_value_one()))	/* q-1 */  | 
    
    
    193  | 
     | 
     | 
    		goto err;  | 
    
    
    194  | 
    ✓✗ | 
    40  | 
    	if (!BN_mul(r0, r1, r2, ctx))			/* (p-1)(q-1) */  | 
    
    
    195  | 
     | 
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    		goto err;  | 
    
    
    196  | 
     | 
     | 
     | 
    
    
    197  | 
     | 
    40  | 
    	BN_with_flags(&pr0, r0, BN_FLG_CONSTTIME);  | 
    
    
    198  | 
     | 
     | 
     | 
    
    
    199  | 
    ✓✗ | 
    40  | 
    	if (!BN_mod_inverse_ct(rsa->d, rsa->e, &pr0, ctx)) /* d */  | 
    
    
    200  | 
     | 
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    		goto err;  | 
    
    
    201  | 
     | 
     | 
     | 
    
    
    202  | 
     | 
     | 
    	/* set up d for correct BN_FLG_CONSTTIME flag */  | 
    
    
    203  | 
     | 
    40  | 
    	BN_with_flags(&d, rsa->d, BN_FLG_CONSTTIME);  | 
    
    
    204  | 
     | 
     | 
     | 
    
    
    205  | 
     | 
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    	/* calculate d mod (p-1) */  | 
    
    
    206  | 
    ✓✗ | 
    40  | 
    	if (!BN_mod_ct(rsa->dmp1, &d, r1, ctx))  | 
    
    
    207  | 
     | 
     | 
    		goto err;  | 
    
    
    208  | 
     | 
     | 
     | 
    
    
    209  | 
     | 
     | 
    	/* calculate d mod (q-1) */  | 
    
    
    210  | 
    ✓✗ | 
    40  | 
    	if (!BN_mod_ct(rsa->dmq1, &d, r2, ctx))  | 
    
    
    211  | 
     | 
     | 
    		goto err;  | 
    
    
    212  | 
     | 
     | 
     | 
    
    
    213  | 
     | 
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    	/* calculate inverse of q mod p */  | 
    
    
    214  | 
     | 
    40  | 
    	BN_with_flags(&p, rsa->p, BN_FLG_CONSTTIME);  | 
    
    
    215  | 
    ✓✗ | 
    40  | 
    	if (!BN_mod_inverse_ct(rsa->iqmp, rsa->q, &p, ctx))  | 
    
    
    216  | 
     | 
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    		goto err;  | 
    
    
    217  | 
     | 
     | 
     | 
    
    
    218  | 
     | 
    40  | 
    	ok = 1;  | 
    
    
    219  | 
     | 
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    err:  | 
    
    
    220  | 
    ✗✓ | 
    40  | 
    	if (ok == -1) { | 
    
    
    221  | 
     | 
     | 
    		RSAerror(ERR_LIB_BN);  | 
    
    
    222  | 
     | 
     | 
    		ok = 0;  | 
    
    
    223  | 
     | 
     | 
    	}  | 
    
    
    224  | 
    ✓✗ | 
    40  | 
    	if (ctx != NULL) { | 
    
    
    225  | 
     | 
    40  | 
    		BN_CTX_end(ctx);  | 
    
    
    226  | 
     | 
    40  | 
    		BN_CTX_free(ctx);  | 
    
    
    227  | 
     | 
    40  | 
    	}  | 
    
    
    228  | 
     | 
     | 
     | 
    
    
    229  | 
     | 
    40  | 
    	return ok;  | 
    
    
    230  | 
     | 
    40  | 
    }  |