mirror of https://github.com/openssl/openssl.git
				
				
				
			
		
			
				
	
	
		
			78 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			78 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
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|  *
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|  * Licensed under the Apache License 2.0 (the "License").  You may not use
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|  * this file except in compliance with the License.  You can obtain a copy
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|  * in the file LICENSE in the source distribution or at
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|  * https://www.openssl.org/source/license.html
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|  */
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| 
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| #include <stdio.h>
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| #include <time.h>
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| #include "internal/cryptlib.h"
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| #include <openssl/bn.h>
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| #include "dsa_locl.h"
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| 
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| static int dsa_builtin_keygen(DSA *dsa);
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| 
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| int DSA_generate_key(DSA *dsa)
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| {
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|     if (dsa->meth->dsa_keygen)
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|         return dsa->meth->dsa_keygen(dsa);
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|     return dsa_builtin_keygen(dsa);
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| }
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| 
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| static int dsa_builtin_keygen(DSA *dsa)
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| {
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|     int ok = 0;
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|     BN_CTX *ctx = NULL;
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|     BIGNUM *pub_key = NULL, *priv_key = NULL;
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| 
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|     if ((ctx = BN_CTX_new()) == NULL)
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|         goto err;
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| 
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|     if (dsa->priv_key == NULL) {
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|         if ((priv_key = BN_secure_new()) == NULL)
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|             goto err;
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|     } else
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|         priv_key = dsa->priv_key;
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| 
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|     do
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|         if (!BN_priv_rand_range(priv_key, dsa->q))
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|             goto err;
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|     while (BN_is_zero(priv_key)) ;
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| 
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|     if (dsa->pub_key == NULL) {
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|         if ((pub_key = BN_new()) == NULL)
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|             goto err;
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|     } else
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|         pub_key = dsa->pub_key;
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| 
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|     {
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|         BIGNUM *prk = BN_new();
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| 
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|         if (prk == NULL)
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|             goto err;
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|         BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
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| 
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|         if (!BN_mod_exp(pub_key, dsa->g, prk, dsa->p, ctx)) {
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|             BN_free(prk);
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|             goto err;
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|         }
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|         /* We MUST free prk before any further use of priv_key */
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|         BN_free(prk);
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|     }
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| 
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|     dsa->priv_key = priv_key;
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|     dsa->pub_key = pub_key;
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|     ok = 1;
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| 
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|  err:
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|     if (pub_key != dsa->pub_key)
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|         BN_free(pub_key);
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|     if (priv_key != dsa->priv_key)
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|         BN_free(priv_key);
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|     BN_CTX_free(ctx);
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|     return ok;
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| }
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