X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=gcrypt.c;h=751c1a4a65d4d0b3b9e5a90242462a83d3fc6cf1;hp=1cfd10964c20e9ab30d77cff432405106cdb6836;hb=42ddd68159d7eff0f3e7c225665c97f9abd59425;hpb=448c8f8e8c1c1eeb88ae468c0c3ab25bed6f2ac8

diff --git a/gcrypt.c b/gcrypt.c
index 1cfd1096..751c1a4a 100644
--- a/gcrypt.c
+++ b/gcrypt.c
@@ -912,11 +912,25 @@ struct stream_cipher {
 	gcry_cipher_hd_t handle;
 };
 
-struct stream_cipher *sc_new(const unsigned char *data, int len)
+struct stream_cipher *sc_new(const unsigned char *data, int len,
+		bool use_aes)
 {
 	gcry_error_t gret;
-
 	struct stream_cipher *sc = para_malloc(sizeof(*sc));
+
+	if (use_aes) {
+		assert(len >= 2 * AES_CRT128_BLOCK_SIZE);
+		gret = gcry_cipher_open(&sc->handle, GCRY_CIPHER_AES128,
+			GCRY_CIPHER_MODE_CTR, 0);
+		assert(gret == 0);
+		gret = gcry_cipher_setkey(sc->handle, data,
+			AES_CRT128_BLOCK_SIZE);
+		assert(gret == 0);
+		gret = gcry_cipher_setctr(sc->handle,
+			data + AES_CRT128_BLOCK_SIZE, AES_CRT128_BLOCK_SIZE);
+		assert(gret == 0);
+		return sc;
+	}
 	gret = gcry_cipher_open(&sc->handle, GCRY_CIPHER_ARCFOUR,
 		GCRY_CIPHER_MODE_STREAM, 0);
 	if (gret) {