X-Git-Url: https://git.openssl.org/gitweb/?a=blobdiff_plain;f=crypto%2Fdsa%2Fdsa_gen.c;h=6a6be3b57537d864aae8d49692f9abb63ee9e427;hb=5c95c2ac23dd30f3c458e2738598383d2ca58181;hp=ca2c8670897079e526a9029eef97acb00d575995;hpb=e9224c717711eefb30038c9b37c69795dda93c9a;p=openssl.git

diff --git a/crypto/dsa/dsa_gen.c b/crypto/dsa/dsa_gen.c
index ca2c867089..6a6be3b575 100644
--- a/crypto/dsa/dsa_gen.c
+++ b/crypto/dsa/dsa_gen.c
@@ -69,6 +69,8 @@
 #define HASH    EVP_sha1()
 #endif 
 
+#include <openssl/opensslconf.h> /* To see if OPENSSL_NO_SHA is defined */
+
 #ifndef OPENSSL_NO_SHA
 
 #include <stdio.h>
@@ -80,10 +82,25 @@
 #include <openssl/rand.h>
 #include <openssl/sha.h>
 
+static int dsa_builtin_paramgen(DSA *ret, int bits,
+		unsigned char *seed_in, int seed_len,
+		int *counter_ret, unsigned long *h_ret, BN_GENCB *cb);
+
 int DSA_generate_parameters_ex(DSA *ret, int bits,
 		unsigned char *seed_in, int seed_len,
 		int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
 	{
+	if(ret->meth->dsa_paramgen)
+		return ret->meth->dsa_paramgen(ret, bits, seed_in, seed_len,
+				counter_ret, h_ret, cb);
+	return dsa_builtin_paramgen(ret, bits, seed_in, seed_len,
+			counter_ret, h_ret, cb);
+	}
+
+static int dsa_builtin_paramgen(DSA *ret, int bits,
+		unsigned char *seed_in, int seed_len,
+		int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
+	{
 	int ok=0;
 	unsigned char seed[SHA_DIGEST_LENGTH];
 	unsigned char md[SHA_DIGEST_LENGTH];
@@ -94,7 +111,7 @@ int DSA_generate_parameters_ex(DSA *ret, int bits,
 	int k,n=0,i,b,m=0;
 	int counter=0;
 	int r=0;
-	BN_CTX *ctx=NULL,*ctx2=NULL,*ctx3=NULL;
+	BN_CTX *ctx=NULL;
 	unsigned int h=2;
 
 	if (bits < 512) bits=512;
@@ -109,22 +126,21 @@ int DSA_generate_parameters_ex(DSA *ret, int bits,
 		memcpy(seed,seed_in,seed_len);
 
 	if ((ctx=BN_CTX_new()) == NULL) goto err;
-	if ((ctx2=BN_CTX_new()) == NULL) goto err;
-	if ((ctx3=BN_CTX_new()) == NULL) goto err;
 
 	if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
 
-	BN_CTX_start(ctx2);
-	r0 = BN_CTX_get(ctx2);
-	g = BN_CTX_get(ctx2);
-	W = BN_CTX_get(ctx2);
-	q = BN_CTX_get(ctx2);
-	X = BN_CTX_get(ctx2);
-	c = BN_CTX_get(ctx2);
-	p = BN_CTX_get(ctx2);
-	test = BN_CTX_get(ctx2);
-
-	BN_lshift(test,BN_value_one(),bits-1);
+	BN_CTX_start(ctx);
+	r0 = BN_CTX_get(ctx);
+	g = BN_CTX_get(ctx);
+	W = BN_CTX_get(ctx);
+	q = BN_CTX_get(ctx);
+	X = BN_CTX_get(ctx);
+	c = BN_CTX_get(ctx);
+	p = BN_CTX_get(ctx);
+	test = BN_CTX_get(ctx);
+
+	if (!BN_lshift(test,BN_value_one(),bits-1))
+		goto err;
 
 	for (;;)
 		{
@@ -167,7 +183,7 @@ int DSA_generate_parameters_ex(DSA *ret, int bits,
 			if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) goto err;
 
 			/* step 4 */
-			r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx3,
+			r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
 					seed_is_random, cb);
 			if (r > 0)
 				break;
@@ -210,27 +226,27 @@ int DSA_generate_parameters_ex(DSA *ret, int bits,
 				/* step 8 */
 				if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,r0))
 					goto err;
-				BN_lshift(r0,r0,160*k);
-				BN_add(W,W,r0);
+				if (!BN_lshift(r0,r0,160*k)) goto err;
+				if (!BN_add(W,W,r0)) goto err;
 				}
 
 			/* more of step 8 */
-			BN_mask_bits(W,bits-1);
-			BN_copy(X,W); /* this should be ok */
-			BN_add(X,X,test); /* this should be ok */
+			if (!BN_mask_bits(W,bits-1)) goto err;
+			if (!BN_copy(X,W)) goto err;
+			if (!BN_add(X,X,test)) goto err;
 
 			/* step 9 */
-			BN_lshift1(r0,q);
-			BN_mod(c,X,r0,ctx);
-			BN_sub(r0,c,BN_value_one());
-			BN_sub(p,X,r0);
+			if (!BN_lshift1(r0,q)) goto err;
+			if (!BN_mod(c,X,r0,ctx)) goto err;
+			if (!BN_sub(r0,c,BN_value_one())) goto err;
+			if (!BN_sub(p,X,r0)) goto err;
 
 			/* step 10 */
 			if (BN_cmp(p,test) >= 0)
 				{
 				/* step 11 */
 				r = BN_is_prime_fasttest_ex(p, DSS_prime_checks,
-						ctx3, 1, cb);
+						ctx, 1, cb);
 				if (r > 0)
 						goto end; /* found it */
 				if (r != 0)
@@ -251,18 +267,18 @@ end:
 
 	/* We now need to generate g */
 	/* Set r0=(p-1)/q */
-	BN_sub(test,p,BN_value_one());
-	BN_div(r0,NULL,test,q,ctx);
+	if (!BN_sub(test,p,BN_value_one())) goto err;
+	if (!BN_div(r0,NULL,test,q,ctx)) goto err;
 
-	BN_set_word(test,h);
-	BN_MONT_CTX_set(mont,p,ctx);
+	if (!BN_set_word(test,h)) goto err;
+	if (!BN_MONT_CTX_set(mont,p,ctx)) goto err;
 
 	for (;;)
 		{
 		/* g=test^r0%p */
-		BN_mod_exp_mont(g,test,r0,p,ctx,mont);
+		if (!BN_mod_exp_mont(g,test,r0,p,ctx,mont)) goto err;
 		if (!BN_is_one(g)) break;
-		BN_add(test,test,BN_value_one());
+		if (!BN_add(test,test,BN_value_one())) goto err;
 		h++;
 		}
 
@@ -279,17 +295,20 @@ err:
 		ret->p=BN_dup(p);
 		ret->q=BN_dup(q);
 		ret->g=BN_dup(g);
+		if (ret->p == NULL || ret->q == NULL || ret->g == NULL)
+			{
+			ok=0;
+			goto err;
+			}
 		if ((m > 1) && (seed_in != NULL)) memcpy(seed_in,seed,20);
 		if (counter_ret != NULL) *counter_ret=counter;
 		if (h_ret != NULL) *h_ret=h;
 		}
-	if (ctx != NULL) BN_CTX_free(ctx);
-	if (ctx2 != NULL)
+	if(ctx)
 		{
-		BN_CTX_end(ctx2);
-		BN_CTX_free(ctx2);
+		BN_CTX_end(ctx);
+		BN_CTX_free(ctx);
 		}
-	if (ctx3 != NULL) BN_CTX_free(ctx3);
 	if (mont != NULL) BN_MONT_CTX_free(mont);
 	return ok;
 	}