Add FFC param/key generation

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10909)

1 files changed, 23 insertions, 11 deletions

diff --git a/crypto/dsa/dsa_key.c b/crypto/dsa/dsa_key.c
index efc125253e..e0a3c82570 100644
--- a/crypto/dsa/dsa_key.c
+++ b/crypto/dsa/dsa_key.c
@@ -11,42 +11,53 @@
 #include <time.h>
 #include "internal/cryptlib.h"
 #include <openssl/bn.h>
+#include "crypto/dsa.h"
 #include "dsa_local.h"
 
-static int dsa_builtin_keygen(DSA *dsa);
+static int dsa_builtin_keygen(OPENSSL_CTX *libctx, DSA *dsa);
 
 int DSA_generate_key(DSA *dsa)
 {
-    if (dsa->meth->dsa_keygen)
+    if (dsa->meth->dsa_keygen != NULL)
         return dsa->meth->dsa_keygen(dsa);
-    return dsa_builtin_keygen(dsa);
+    return dsa_builtin_keygen(NULL, dsa);
 }
 
-static int dsa_builtin_keygen(DSA *dsa)
+int dsa_generate_key_ctx(OPENSSL_CTX *libctx, DSA *dsa)
+{
+#ifndef FIPS_MODE
+    if (dsa->meth->dsa_keygen != NULL)
+        return dsa->meth->dsa_keygen(dsa);
+#endif
+    return dsa_builtin_keygen(libctx, dsa);
+}
+
+static int dsa_builtin_keygen(OPENSSL_CTX *libctx, DSA *dsa)
 {
     int ok = 0;
     BN_CTX *ctx = NULL;
     BIGNUM *pub_key = NULL, *priv_key = NULL;
 
-    if ((ctx = BN_CTX_new()) == NULL)
+    if ((ctx = BN_CTX_new_ex(libctx)) == NULL)
         goto err;
 
     if (dsa->priv_key == NULL) {
         if ((priv_key = BN_secure_new()) == NULL)
             goto err;
-    } else
+    } else {
         priv_key = dsa->priv_key;
+    }
 
-    do
-        if (!BN_priv_rand_range(priv_key, dsa->params.q))
-            goto err;
-    while (BN_is_zero(priv_key)) ;
+    if (!ffc_generate_private_key(ctx, &dsa->params, BN_num_bits(dsa->params.q),
+                                  112, priv_key))
+        goto err;
 
     if (dsa->pub_key == NULL) {
         if ((pub_key = BN_new()) == NULL)
             goto err;
-    } else
+    } else {
         pub_key = dsa->pub_key;
+    }
 
     {
         BIGNUM *prk = BN_new();
@@ -55,6 +66,7 @@ static int dsa_builtin_keygen(DSA *dsa)
             goto err;
         BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
 
+        /* pub_key = g ^ priv_key mod p */
         if (!BN_mod_exp(pub_key, dsa->params.g, prk, dsa->params.p, ctx)) {
             BN_free(prk);
             goto err;