Implementat the ntor handshake

The ntor handshake--described in proposal 216 and in a paper by
Goldberg, Stebila, and Ustaoglu--gets us much better performance than
our current approach.

1 files changed, 49 insertions, 0 deletions

diff --git a/src/or/onion_ntor.h b/src/or/onion_ntor.h
new file mode 100644
index 0000000000..03b83da5f2
--- /dev/null
+++ b/src/or/onion_ntor.h
@@ -0,0 +1,49 @@
+/* Copyright (c) 2012, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+#ifndef TOR_ONION_NTOR_H
+#define TOR_ONION_NTOR_H
+
+#include "torint.h"
+#include "crypto_curve25519.h"
+#include "di_ops.h"
+
+/** State to be maintained by a client between sending an ntor onionskin
+ * and receiving a reply. */
+typedef struct ntor_handshake_state_t ntor_handshake_state_t;
+
+/** Length of an ntor onionskin, as sent from the client to server. */
+#define NTOR_ONIONSKIN_LEN 84
+/** Length of an ntor reply, as sent from server to client. */
+#define NTOR_REPLY_LEN 64
+
+/** A paired public and private key for curve25519.
+ * XXXX024 move this structure somewhere smarter.
+ **/
+typedef struct curve25519_keypair_t {
+  curve25519_public_key_t pubkey;
+  curve25519_secret_key_t seckey;
+} curve25519_keypair_t;
+
+void ntor_handshake_state_free(ntor_handshake_state_t *state);
+
+int onion_skin_ntor_create(const uint8_t *router_id,
+                           const curve25519_public_key_t *router_key,
+                           ntor_handshake_state_t **handshake_state_out,
+                           uint8_t *onion_skin_out);
+
+int onion_skin_ntor_server_handshake(const uint8_t *onion_skin,
+                                 const di_digest256_map_t *private_keys,
+                                 const uint8_t *my_node_id,
+                                 uint8_t *handshake_reply_out,
+                                 uint8_t *key_out,
+                                 size_t key_out_len);
+
+int onion_skin_ntor_client_handshake(
+                             const ntor_handshake_state_t *handshake_state,
+                             const uint8_t *handshake_reply,
+                             uint8_t *key_out,
+                             size_t key_out_len);
+
+#endif
+