dh-speed: Don't reuse DH object

Since the changes to the DH implementations that were merged with 30faf04 ("Merge branch 'multi-ke-backport'"), most implementations don't support deriving different shared secrets for the same private key by calling set_public_key() with another public key anymore (some prevent it explicitly, but reusing DH private keys is not something we want to support anyway). So we can't reuse the DH object on one side for every round.
mpfeiffermway · Jan 6, 2023 · a59a6d4 · a59a6d4
1 parent 0c7bfec
commit a59a6d4
Showing 1 changed file with 21 additions and 16 deletions.
diff --git a/scripts/dh_speed.c b/scripts/dh_speed.c
@@ -67,54 +67,59 @@ static double end_timing(struct timespec *start)
 
 static void run_test(key_exchange_method_t group, int rounds)
 {
-	key_exchange_t *l[rounds], *r;
-	chunk_t chunk, chunks[rounds], lsecrets[rounds], rsecrets[rounds];
+	key_exchange_t *l[rounds], *r[rounds];
+	chunk_t lpublic[rounds], rpublic[rounds], lsecret[rounds], rsecret[rounds];
 	struct timespec timing;
 	int round;
 
-	r = lib->crypto->create_ke(lib->crypto, group);
-	if (!r)
+	r[0] = lib->crypto->create_ke(lib->crypto, group);
+	if (!r[0])
 	{
 		printf("skipping %N, not supported\n", key_exchange_method_names,
 			   group);
 		return;
 	}
+	assert(r[0]->get_public_key(r[0], &rpublic[0]));
+	for (round = 1; round < rounds; round++)
+	{
+		r[round] = lib->crypto->create_ke(lib->crypto, group);
+		assert(r[round]->get_public_key(r[round], &rpublic[round]));
+	}
 
 	printf("%N:\t", key_exchange_method_names, group);
 
 	start_timing(&timing);
 	for (round = 0; round < rounds; round++)
 	{
 		l[round] = lib->crypto->create_ke(lib->crypto, group);
-		assert(l[round]->get_public_key(l[round], &chunks[round]));
+		assert(l[round]->get_public_key(l[round], &lpublic[round]));
 	}
 	printf("A = g^a/s: %8.1f", rounds / end_timing(&timing));
 
 	for (round = 0; round < rounds; round++)
 	{
-		assert(r->set_public_key(r, chunks[round]));
-		assert(r->get_shared_secret(r, &rsecrets[round]));
-		chunk_free(&chunks[round]);
+		assert(r[round]->set_public_key(r[round], lpublic[round]));
+		assert(r[round]->get_shared_secret(r[round], &rsecret[round]));
+		chunk_free(&lpublic[round]);
 	}
 
-	assert(r->get_public_key(r, &chunk));
 	start_timing(&timing);
 	for (round = 0; round < rounds; round++)
 	{
-		assert(l[round]->set_public_key(l[round], chunk));
-		assert(l[round]->get_shared_secret(l[round], &lsecrets[round]));
+		assert(l[round]->set_public_key(l[round], rpublic[round]));
+		assert(l[round]->get_shared_secret(l[round], &lsecret[round]));
 	}
 	printf(" | S = B^a/s: %8.1f\n", rounds / end_timing(&timing));
-	chunk_free(&chunk);
 
 	for (round = 0; round < rounds; round++)
 	{
-		assert(chunk_equals(rsecrets[round], lsecrets[round]));
-		free(lsecrets[round].ptr);
-		free(rsecrets[round].ptr);
+		assert(chunk_equals(rsecret[round], lsecret[round]));
+		chunk_free(&lsecret[round]);
+		chunk_free(&rsecret[round]);
+		chunk_free(&rpublic[round]);
 		l[round]->destroy(l[round]);
+		r[round]->destroy(r[round]);
 	}
-	r->destroy(r);
 }
 
 int main(int argc, char *argv[])