Fix bug in DSA parameter generation code which stopped it copying a

generated random seed to the supplied seed parameter.

3 files changed, 97 insertions, 4 deletions

diff --git a/crypto/dsa/dsa_gen.c b/crypto/dsa/dsa_gen.c
index 9ad985b..6f1728e 100644
--- a/crypto/dsa/dsa_gen.c
+++ b/crypto/dsa/dsa_gen.c
@@ -119,13 +119,20 @@ static int dsa_builtin_paramgen(DSA *ret, int bits,
 	if (bits < 512) bits=512;
 	bits=(bits+63)/64*64;
 
-	if (seed_len < 20)
+	/* NB: seed_len == 0 is special case: copy generated seed to
+ 	 * seed_in if it is not NULL.
+ 	 */
+	if (seed_len && (seed_len < 20))
 		seed_in = NULL; /* seed buffer too small -- ignore */
 	if (seed_len > 20) 
 		seed_len = 20; /* App. 2.2 of FIPS PUB 186 allows larger SEED,
 		                * but our internal buffers are restricted to 160 bits*/
 	if ((seed_in != NULL) && (seed_len == 20))
+		{
 		memcpy(seed,seed_in,seed_len);
+		/* set seed_in to NULL to avoid it being copied back */
+		seed_in = NULL;
+		}
 
 	if ((ctx=BN_CTX_new()) == NULL) goto err;
 
@@ -302,7 +309,7 @@ err:
 			ok=0;
 			goto err;
 			}
-		if ((m > 1) && (seed_in != NULL)) memcpy(seed_in,seed,20);
+		if (seed_in != NULL) memcpy(seed_in,seed,20);
 		if (counter_ret != NULL) *counter_ret=counter;
 		if (h_ret != NULL) *h_ret=h;
 		}
diff --git a/fips/dsa/fips_dsa_gen.c b/fips/dsa/fips_dsa_gen.c
index c666e5b..0cecf34 100644
--- a/fips/dsa/fips_dsa_gen.c
+++ b/fips/dsa/fips_dsa_gen.c
@@ -133,13 +133,20 @@ static int dsa_builtin_paramgen(DSA *ret, int bits,
 	if (bits < 512) bits=512;
 	bits=(bits+63)/64*64;
 
-	if (seed_len < 20)
+	/* NB: seed_len == 0 is special case: copy generated seed to
+ 	 * seed_in if it is not NULL.
+ 	 */
+	if (seed_len && (seed_len < 20))
 		seed_in = NULL; /* seed buffer too small -- ignore */
 	if (seed_len > 20) 
 		seed_len = 20; /* App. 2.2 of FIPS PUB 186 allows larger SEED,
 		                * but our internal buffers are restricted to 160 bits*/
 	if ((seed_in != NULL) && (seed_len == 20))
+		{
 		memcpy(seed,seed_in,seed_len);
+		/* set seed_in to NULL to avoid it being copied back */
+		seed_in = NULL;
+		}
 
 	if ((ctx=BN_CTX_new()) == NULL) goto err;
 
@@ -316,7 +323,7 @@ err:
 			ok=0;
 			goto err;
 			}
-		if ((m > 1) && (seed_in != NULL)) memcpy(seed_in,seed,20);
+		if (seed_in != NULL) memcpy(seed_in,seed,20);
 		if (counter_ret != NULL) *counter_ret=counter;
 		if (h_ret != NULL) *h_ret=h;
 		}
diff --git a/fips/dsa/fips_dssvs.c b/fips/dsa/fips_dssvs.c
index c896351..45f97cd 100644
--- a/fips/dsa/fips_dssvs.c
+++ b/fips/dsa/fips_dssvs.c
@@ -112,6 +112,83 @@ void pqg()
 	}
     }
 
+
+void pqgver()
+    {
+    char buf[1024];
+    char lbuf[1024];
+    char *keyword, *value;
+    BIGNUM *p = NULL, *q = NULL, *g = NULL;
+    int counter, counter2;
+    unsigned long h, h2;
+    DSA *dsa=NULL;
+    int nmod=0;
+    unsigned char seed[1024];
+
+    while(fgets(buf,sizeof buf,stdin) != NULL)
+	{
+	if (!parse_line(&keyword, &value, lbuf, buf))
+		{
+		fputs(buf,stdout);
+		continue;
+		}
+	if(!strcmp(keyword,"[mod"))
+	    nmod=atoi(value);
+	else if(!strcmp(keyword,"P"))
+	    p=hex2bn(value);
+	else if(!strcmp(keyword,"Q"))
+	    q=hex2bn(value);
+	else if(!strcmp(keyword,"G"))
+	    g=hex2bn(value);
+	else if(!strcmp(keyword,"Seed"))
+	    {
+	    int slen = hex2bin(value, seed);
+	    if (slen != 20)
+		{
+		fprintf(stderr, "Seed parse length error\n");
+		exit (1);
+		}
+	    }
+	else if(!strcmp(keyword,"c"))
+	    counter =atoi(buf+4);
+	else if(!strcmp(keyword,"H"))
+	    {
+	    h = atoi(value);
+	    if (!p || !q || !g)
+		{
+		fprintf(stderr, "Parse Error\n");
+		exit (1);
+		}
+	    pbn("P",p);
+	    pbn("Q",q);
+	    pbn("G",g);
+	    pv("Seed",seed,20);
+	    printf("c = %d\n",counter);
+	    printf("H = %lx\n",h);
+	    dsa = FIPS_dsa_new();
+	    if (!DSA_generate_parameters_ex(dsa, nmod,seed,20 ,&counter2,&h2,NULL))
+			{
+			do_print_errors();
+			exit(1);
+			}
+            if (BN_cmp(dsa->p, p) || BN_cmp(dsa->q, q) || BN_cmp(dsa->g, g)
+		|| (counter != counter2) || (h != h2))
+	    	printf("Result = F\n");
+	    else
+	    	printf("Result = T\n");
+	    BN_free(p);
+	    BN_free(q);
+	    BN_free(g);
+	    p = NULL;
+	    q = NULL;
+	    g = NULL;
+	    FIPS_dsa_free(dsa);
+	    dsa = NULL;
+	    }
+	}
+    }
+
+
 void keypair()
     {
     char buf[1024];
@@ -329,6 +406,8 @@ int main(int argc,char **argv)
 	primes();
     else if(!strcmp(argv[1],"pqg"))
 	pqg();
+    else if(!strcmp(argv[1],"pqgver"))
+	pqgver();
     else if(!strcmp(argv[1],"keypair"))
 	keypair();
     else if(!strcmp(argv[1],"siggen"))