Convert dsa_keypair_from_sexp_alist to use struct dsa_params.

ChangeLog

 2014-03-26  Niels Möller  <nisse@lysator.liu.se>
 
+	* sexp2dsa.c (dsa_keypair_from_sexp_alist): Converted to new DSA
+	interface. Allow q_size == 0, meaning any q < p is allowed.
+	Additional validity checks.
+	(dsa_sha1_keypair_from_sexp, dsa_sha256_keypair_from_sexp):
+	Converted to new DSA interface.
+
 	* dsa2sexp.c (dsa_keypair_to_sexp): Converted to new DSA
 	interface.
 	* tools/pkcs1-conv.c: Updated uses of dsa_keypair_to_sexp.

dsa.h

@@ -256,8 +256,9 @@ dsa_signature_from_sexp(struct dsa_signature *rs,
 			unsigned q_bits);
 
 int
-dsa_keypair_from_sexp_alist(struct dsa_public_key *pub,
-			    struct dsa_private_key *priv,
+dsa_keypair_from_sexp_alist(struct dsa_params *params,
+			    mpz_t pub,
+			    mpz_t priv,
 			    unsigned p_max_bits,
 			    unsigned q_bits,
 			    struct sexp_iterator *i);
@@ -267,14 +268,16 @@ dsa_keypair_from_sexp_alist(struct dsa_public_key *pub,
  * the public key. */
 /* Keys must be initialized before calling this function, as usual. */
 int
-dsa_sha1_keypair_from_sexp(struct dsa_public_key *pub,
-			   struct dsa_private_key *priv,
+dsa_sha1_keypair_from_sexp(struct dsa_params *params,
+			   mpz_t pub,
+			   mpz_t priv,
 			   unsigned p_max_bits,
 			   size_t length, const uint8_t *expr);
 
 int
-dsa_sha256_keypair_from_sexp(struct dsa_public_key *pub,
-			     struct dsa_private_key *priv,
+dsa_sha256_keypair_from_sexp(struct dsa_params *params,
+			     mpz_t pub,
+			     mpz_t priv,
 			     unsigned p_max_bits,
 			     size_t length, const uint8_t *expr);
 

examples/hogweed-benchmark.c

@@ -303,7 +303,9 @@ bench_dsa_init (unsigned size)
   if (! (sexp_transport_iterator_first (&i, sizeof(dsa1024) - 1, dsa1024)
 	 && sexp_iterator_check_type (&i, "private-key")
 	 && sexp_iterator_check_type (&i, "dsa")
-	 && dsa_keypair_from_sexp_alist (&ctx->pub, &ctx->key, 0, DSA_SHA1_Q_BITS, &i)) )
+	 && dsa_keypair_from_sexp_alist ((struct dsa_params *) &ctx->pub,
+					 ctx->pub.y, ctx->key.x,
+					 0, DSA_SHA1_Q_BITS, &i)) )
     die ("Internal error.\n");
 
   ctx->digest = hash_string (&nettle_sha1, 3, "foo");

sexp2dsa.c

@@ -47,8 +47,9 @@ do {						\
  */
 
 int
-dsa_keypair_from_sexp_alist(struct dsa_public_key *pub,
-			    struct dsa_private_key *priv,
+dsa_keypair_from_sexp_alist(struct dsa_params *params,
+			    mpz_t pub,
+			    mpz_t priv,
 			    unsigned p_max_bits,
 			    unsigned q_bits,
 			    struct sexp_iterator *i)
@@ -57,26 +58,39 @@ dsa_keypair_from_sexp_alist(struct dsa_public_key *pub,
     = { "p", "q", "g", "y", "x" };
   struct sexp_iterator values[5];
   unsigned nvalues = priv ? 5 : 4;
-  
+  unsigned p_bits;
+
   if (!sexp_iterator_assoc(i, nvalues, names, values))
     return 0;
 
-  if (priv)
-    GET(priv->x, q_bits, &values[4]);
-  
-  GET(pub->p, p_max_bits, &values[0]);
-  GET(pub->q, q_bits, &values[1]);
-  if (mpz_sizeinbase(pub->q, 2) != q_bits)
+  GET(params->p, p_max_bits, &values[0]);
+  p_bits = mpz_sizeinbase (params->p, 2);
+  GET(params->q, q_bits ? q_bits : p_bits, &values[1]);
+  if (q_bits > 0 && mpz_sizeinbase(params->q, 2) != q_bits)
+    return 0;
+  if (mpz_cmp (params->q, params->p) >= 0)
+    return 0;
+  GET(params->g, p_bits, &values[2]);
+  if (mpz_cmp (params->g, params->p) >= 0)
     return 0;
-  GET(pub->g, p_max_bits, &values[2]);
-  GET(pub->y, p_max_bits, &values[3]);
-  
+  GET(pub, p_bits, &values[3]);
+  if (mpz_cmp (pub, params->p) >= 0)
+    return 0;
+
+  if (priv)
+    {
+      GET(priv, mpz_sizeinbase (params->q, 2), &values[4]);
+      if (mpz_cmp (priv, params->q) >= 0)
+	return 0;
+    }
+
   return 1;
 }
 
 int
-dsa_sha1_keypair_from_sexp(struct dsa_public_key *pub,
-			   struct dsa_private_key *priv,
+dsa_sha1_keypair_from_sexp(struct dsa_params *params,
+			   mpz_t pub,
+			   mpz_t priv,
 			   unsigned p_max_bits, 
 			   size_t length, const uint8_t *expr)
 {
@@ -85,12 +99,14 @@ dsa_sha1_keypair_from_sexp(struct dsa_public_key *pub,
   return sexp_iterator_first(&i, length, expr)
     && sexp_iterator_check_type(&i, priv ? "private-key" : "public-key")
     && sexp_iterator_check_type(&i, "dsa")
-    && dsa_keypair_from_sexp_alist(pub, priv, p_max_bits, DSA_SHA1_Q_BITS, &i);
+    && dsa_keypair_from_sexp_alist(params, pub, priv,
+				   p_max_bits, DSA_SHA1_Q_BITS, &i);
 }
 
 int
-dsa_sha256_keypair_from_sexp(struct dsa_public_key *pub,
-			     struct dsa_private_key *priv,
+dsa_sha256_keypair_from_sexp(struct dsa_params *params,
+			     mpz_t pub,
+			     mpz_t priv,
 			     unsigned p_max_bits, 
 			     size_t length, const uint8_t *expr)
 {
@@ -99,7 +115,8 @@ dsa_sha256_keypair_from_sexp(struct dsa_public_key *pub,
   return sexp_iterator_first(&i, length, expr)
     && sexp_iterator_check_type(&i, priv ? "private-key" : "public-key")
     && sexp_iterator_check_type(&i, "dsa-sha256")
-    && dsa_keypair_from_sexp_alist(pub, priv, p_max_bits, DSA_SHA256_Q_BITS, &i);
+    && dsa_keypair_from_sexp_alist(params, pub, priv,
+				   p_max_bits, DSA_SHA256_Q_BITS, &i);
 }
 
 int