1 files changed, 23 insertions, 16 deletions

diff --git a/include/olm/ratchet.hh b/include/olm/ratchet.hh
index 2393e5b..2e87e35 100644
--- a/include/olm/ratchet.hh
+++ b/include/olm/ratchet.hh
@@ -13,23 +13,29 @@
  * limitations under the License.
  */
 
-#include "olm/crypto.hh"
+#include <cstdint>
+
+#include "olm/crypto.h"
 #include "olm/list.hh"
-#include "olm/error.hh"
+#include "olm/error.h"
 
-namespace olm {
+struct _olm_cipher;
 
-class Cipher;
+namespace olm {
 
-typedef std::uint8_t SharedKey[olm::KEY_LENGTH];
+/** length of a shared key: the root key R(i), chain key C(i,j), and message key
+ * M(i,j)). They are all only used to stuff into HMACs, so could be any length
+ * for that. The chain key and message key are both derived from SHA256
+ * operations, so their length is determined by that. */
+const std::size_t OLM_SHARED_KEY_LENGTH = SHA256_OUTPUT_LENGTH;
 
+typedef std::uint8_t SharedKey[OLM_SHARED_KEY_LENGTH];
 
 struct ChainKey {
     std::uint32_t index;
     SharedKey key;
 };
 
-
 struct MessageKey {
     std::uint32_t index;
     SharedKey key;
@@ -37,19 +43,19 @@ struct MessageKey {
 
 
 struct SenderChain {
-    Curve25519KeyPair ratchet_key;
+    _olm_curve25519_key_pair ratchet_key;
     ChainKey chain_key;
 };
 
 
 struct ReceiverChain {
-    Curve25519PublicKey ratchet_key;
+    _olm_curve25519_public_key ratchet_key;
     ChainKey chain_key;
 };
 
 
 struct SkippedMessageKey {
-    Curve25519PublicKey ratchet_key;
+    _olm_curve25519_public_key ratchet_key;
     MessageKey message_key;
 };
 
@@ -70,20 +76,20 @@ struct Ratchet {
 
     Ratchet(
         KdfInfo const & kdf_info,
-        Cipher const & ratchet_cipher
+        _olm_cipher const *ratchet_cipher
     );
 
     /** A some strings identifying the application to feed into the KDF. */
     KdfInfo const & kdf_info;
 
     /** The AEAD cipher to use for encrypting messages. */
-    Cipher const & ratchet_cipher;
+    _olm_cipher const *ratchet_cipher;
 
     /** The last error that happened encrypting or decrypting a message. */
-    ErrorCode last_error;
+    OlmErrorCode last_error;
 
     /** The root key is used to generate chain keys from the ephemeral keys.
-     * A new root_key derived each time a chain key is derived. */
+     * A new root_key derived each time a new chain is started. */
     SharedKey root_key;
 
     /** The sender chain is used to send messages. Each time a new ephemeral
@@ -104,14 +110,14 @@ struct Ratchet {
      * remote's first ratchet key */
     void initialise_as_bob(
         std::uint8_t const * shared_secret, std::size_t shared_secret_length,
-        Curve25519PublicKey const & their_ratchet_key
+        _olm_curve25519_public_key const & their_ratchet_key
     );
 
     /** Initialise the session using a shared secret and the public/private key
      * pair for the first ratchet key */
     void initialise_as_alice(
         std::uint8_t const * shared_secret, std::size_t shared_secret_length,
-        Curve25519KeyPair const & our_ratchet_key
+        _olm_curve25519_key_pair const & our_ratchet_key
     );
 
     /** The number of bytes of output the encrypt method will write for
@@ -170,7 +176,8 @@ std::uint8_t * pickle(
 
 std::uint8_t const * unpickle(
     std::uint8_t const * pos, std::uint8_t const * end,
-    Ratchet & value
+    Ratchet & value,
+    bool includes_chain_index
 );