Convert Ed25519 and Curve25519 functions to plain C

7 files changed, 106 insertions, 88 deletions

diff --git a/src/account.cpp b/src/account.cpp
index 9512068..c77f95c 100644
--- a/src/account.cpp
+++ b/src/account.cpp
@@ -24,10 +24,10 @@ olm::Account::Account(
 
 
 olm::OneTimeKey const * olm::Account::lookup_key(
-    olm::Curve25519PublicKey const & public_key
+    _olm_curve25519_public_key const & public_key
 ) {
     for (olm::OneTimeKey const & key : one_time_keys) {
-        if (olm::array_equal(key.key.public_key, public_key.public_key)) {
+        if (olm::array_equal(key.key.public_key.public_key, public_key.public_key)) {
             return &key;
         }
     }
@@ -35,11 +35,11 @@ olm::OneTimeKey const * olm::Account::lookup_key(
 }
 
 std::size_t olm::Account::remove_key(
-    olm::Curve25519PublicKey const & public_key
+    _olm_curve25519_public_key const & public_key
 ) {
     OneTimeKey * i;
     for (i = one_time_keys.begin(); i != one_time_keys.end(); ++i) {
-        if (olm::array_equal(i->key.public_key, public_key.public_key)) {
+        if (olm::array_equal(i->key.public_key.public_key, public_key.public_key)) {
             std::uint32_t id = i->id;
             one_time_keys.erase(i);
             return id;
@@ -60,9 +60,9 @@ std::size_t olm::Account::new_account(
         return std::size_t(-1);
     }
 
-    olm::ed25519_generate_key(random, identity_keys.ed25519_key);
+    _olm_crypto_ed25519_generate_key(random, &identity_keys.ed25519_key);
     random += ED25519_RANDOM_LENGTH;
-    olm::curve25519_generate_key(random, identity_keys.curve25519_key);
+    _olm_crypto_curve25519_generate_key(random, &identity_keys.curve25519_key);
 
     return 0;
 }
@@ -118,16 +118,16 @@ std::size_t olm::Account::get_identity_json(
     pos = write_string(pos, KEY_JSON_CURVE25519);
     *(pos++) = '\"';
     pos = olm::encode_base64(
-        identity_keys.curve25519_key.public_key,
-        sizeof(identity_keys.curve25519_key.public_key),
+        identity_keys.curve25519_key.public_key.public_key,
+        sizeof(identity_keys.curve25519_key.public_key.public_key),
         pos
     );
     *(pos++) = '\"'; *(pos++) = ',';
     pos = write_string(pos, KEY_JSON_ED25519);
     *(pos++) = '\"';
     pos = olm::encode_base64(
-        identity_keys.ed25519_key.public_key,
-        sizeof(identity_keys.ed25519_key.public_key),
+        identity_keys.ed25519_key.public_key.public_key,
+        sizeof(identity_keys.ed25519_key.public_key.public_key),
         pos
     );
     *(pos++) = '\"'; *(pos++) = '}';
@@ -149,8 +149,8 @@ std::size_t olm::Account::sign(
         last_error = OlmErrorCode::OLM_OUTPUT_BUFFER_TOO_SMALL;
         return std::size_t(-1);
     }
-    olm::ed25519_sign(
-        identity_keys.ed25519_key, message, message_length, signature
+    _olm_crypto_ed25519_sign(
+        &identity_keys.ed25519_key, message, message_length, signature
     );
     return this->signature_length();
 }
@@ -202,7 +202,7 @@ std::size_t olm::Account::get_one_time_keys_json(
         pos = olm::encode_base64(key_id, sizeof(key_id), pos);
         *(pos++) = '\"'; *(pos++) = ':'; *(pos++) = '\"';
         pos = olm::encode_base64(
-            key.key.public_key, sizeof(key.key.public_key), pos
+            key.key.public_key.public_key, sizeof(key.key.public_key.public_key), pos
         );
         *(pos++) = '\"';
         sep = ',';
@@ -253,7 +253,7 @@ std::size_t olm::Account::generate_one_time_keys(
         OneTimeKey & key = *one_time_keys.insert(one_time_keys.begin());
         key.id = ++next_one_time_key_id;
         key.published = false;
-        olm::curve25519_generate_key(random, key.key);
+        _olm_crypto_curve25519_generate_key(random, &key.key);
         random += CURVE25519_RANDOM_LENGTH;
     }
     return number_of_keys;
diff --git a/src/crypto.cpp b/src/crypto.cpp
index 0b08c54..89d9d72 100644
--- a/src/crypto.cpp
+++ b/src/crypto.cpp
@@ -100,59 +100,65 @@ inline static void hmac_sha256_final(
 
 } // namespace
 
-void olm::curve25519_generate_key(
-    std::uint8_t const * random_32_bytes,
-    olm::Curve25519KeyPair & key_pair
+void _olm_crypto_curve25519_generate_key(
+    uint8_t const * random_32_bytes,
+    struct _olm_curve25519_key_pair *key_pair
 ) {
-    std::memcpy(key_pair.private_key, random_32_bytes, CURVE25519_KEY_LENGTH);
+    std::memcpy(
+        key_pair->private_key.private_key, random_32_bytes,
+        CURVE25519_KEY_LENGTH
+    );
     ::curve25519_donna(
-        key_pair.public_key, key_pair.private_key, CURVE25519_BASEPOINT
+        key_pair->public_key.public_key,
+        key_pair->private_key.private_key,
+        CURVE25519_BASEPOINT
     );
 }
 
 
-void olm::curve25519_shared_secret(
-    olm::Curve25519KeyPair const & our_key,
-    olm::Curve25519PublicKey const & their_key,
+void _olm_crypto_curve25519_shared_secret(
+    const struct _olm_curve25519_key_pair *our_key,
+    const struct _olm_curve25519_public_key * their_key,
     std::uint8_t * output
 ) {
-    ::curve25519_donna(output, our_key.private_key, their_key.public_key);
+    ::curve25519_donna(output, our_key->private_key.private_key, their_key->public_key);
 }
 
 
-void olm::ed25519_generate_key(
+void _olm_crypto_ed25519_generate_key(
     std::uint8_t const * random_32_bytes,
-    olm::Ed25519KeyPair & key_pair
+    struct _olm_ed25519_key_pair *key_pair
 ) {
     ::ed25519_create_keypair(
-        key_pair.public_key, key_pair.private_key,
+        key_pair->public_key.public_key, key_pair->private_key.private_key,
         random_32_bytes
     );
 }
 
 
-void olm::ed25519_sign(
-    olm::Ed25519KeyPair const & our_key,
+void _olm_crypto_ed25519_sign(
+    const struct _olm_ed25519_key_pair *our_key,
     std::uint8_t const * message, std::size_t message_length,
     std::uint8_t * output
 ) {
     ::ed25519_sign(
         output,
         message, message_length,
-        our_key.public_key, our_key.private_key
+        our_key->public_key.public_key,
+        our_key->private_key.private_key
     );
 }
 
 
-bool olm::ed25519_verify(
-    olm::Ed25519PublicKey const & their_key,
+int _olm_crypto_ed25519_verify(
+    const struct _olm_ed25519_public_key *their_key,
     std::uint8_t const * message, std::size_t message_length,
     std::uint8_t const * signature
 ) {
     return 0 != ::ed25519_verify(
         signature,
         message, message_length,
-        their_key.public_key
+        their_key->public_key
     );
 }
 
diff --git a/src/olm.cpp b/src/olm.cpp
index 3fe9c5e..d3af19c 100644
--- a/src/olm.cpp
+++ b/src/olm.cpp
@@ -442,8 +442,8 @@ size_t olm_create_outbound_session(
         from_c(session)->last_error = OlmErrorCode::OLM_INVALID_BASE64;
         return std::size_t(-1);
     }
-    olm::Curve25519PublicKey identity_key;
-    olm::Curve25519PublicKey one_time_key;
+    _olm_curve25519_public_key identity_key;
+    _olm_curve25519_public_key one_time_key;
 
     olm::decode_base64(id_key, id_key_length, identity_key.public_key);
     olm::decode_base64(ot_key, ot_key_length, one_time_key.public_key);
@@ -487,7 +487,7 @@ size_t olm_create_inbound_session_from(
         from_c(session)->last_error = OlmErrorCode::OLM_INVALID_BASE64;
         return std::size_t(-1);
     }
-    olm::Curve25519PublicKey identity_key;
+    _olm_curve25519_public_key identity_key;
     olm::decode_base64(id_key, id_key_length, identity_key.public_key);
 
     std::size_t raw_length = b64_input(
@@ -564,7 +564,7 @@ size_t olm_matches_inbound_session_from(
         from_c(session)->last_error = OlmErrorCode::OLM_INVALID_BASE64;
         return std::size_t(-1);
     }
-    olm::Curve25519PublicKey identity_key;
+    _olm_curve25519_public_key identity_key;
     olm::decode_base64(id_key, id_key_length, identity_key.public_key);
 
     std::size_t raw_length = b64_input(
@@ -720,7 +720,7 @@ size_t olm_ed25519_verify(
         from_c(utility)->last_error = OlmErrorCode::OLM_INVALID_BASE64;
         return std::size_t(-1);
     }
-    olm::Ed25519PublicKey verify_key;
+    _olm_ed25519_public_key verify_key;
     olm::decode_base64(from_c(key), key_length, verify_key.public_key);
     std::size_t raw_signature_length = b64_input(
         from_c(signature), signature_length, from_c(utility)->last_error
diff --git a/src/pickle.cpp b/src/pickle.cpp
index fc3e2b4..e9708b7 100644
--- a/src/pickle.cpp
+++ b/src/pickle.cpp
@@ -71,7 +71,7 @@ std::uint8_t const * olm::unpickle_bytes(
 
 
 std::size_t olm::pickle_length(
-    const olm::Curve25519PublicKey & value
+    const _olm_curve25519_public_key & value
 ) {
     return sizeof(value.public_key);
 }
@@ -79,7 +79,7 @@ std::size_t olm::pickle_length(
 
 std::uint8_t * olm::pickle(
     std::uint8_t * pos,
-    const olm::Curve25519PublicKey & value
+    const _olm_curve25519_public_key & value
 ) {
     pos = olm::pickle_bytes(
         pos, value.public_key, sizeof(value.public_key)
@@ -90,7 +90,7 @@ std::uint8_t * olm::pickle(
 
 std::uint8_t const * olm::unpickle(
     std::uint8_t const * pos, std::uint8_t const * end,
-    olm::Curve25519PublicKey & value
+    _olm_curve25519_public_key & value
 ) {
     pos = olm::unpickle_bytes(
         pos, end, value.public_key, sizeof(value.public_key)
@@ -101,21 +101,24 @@ std::uint8_t const * olm::unpickle(
 
 
 std::size_t olm::pickle_length(
-    const olm::Curve25519KeyPair & value
+    const _olm_curve25519_key_pair & value
 ) {
-    return sizeof(value.public_key) + sizeof(value.private_key);
+    return sizeof(value.public_key.public_key)
+        + sizeof(value.private_key.private_key);
 }
 
 
 std::uint8_t * olm::pickle(
     std::uint8_t * pos,
-    const olm::Curve25519KeyPair & value
+    const _olm_curve25519_key_pair & value
 ) {
     pos = olm::pickle_bytes(
-        pos, value.public_key, sizeof(value.public_key)
+        pos, value.public_key.public_key,
+        sizeof(value.public_key.public_key)
     );
     pos = olm::pickle_bytes(
-        pos, value.private_key, sizeof(value.private_key)
+        pos, value.private_key.private_key,
+        sizeof(value.private_key.private_key)
     );
     return pos;
 }
@@ -123,19 +126,21 @@ std::uint8_t * olm::pickle(
 
 std::uint8_t const * olm::unpickle(
     std::uint8_t const * pos, std::uint8_t const * end,
-    olm::Curve25519KeyPair & value
+    _olm_curve25519_key_pair & value
 ) {
     pos = olm::unpickle_bytes(
-        pos, end, value.public_key, sizeof(value.public_key)
+        pos, end, value.public_key.public_key,
+        sizeof(value.public_key.public_key)
     );
     pos = olm::unpickle_bytes(
-        pos, end, value.private_key, sizeof(value.private_key)
+        pos, end, value.private_key.private_key,
+        sizeof(value.private_key.private_key)
     );
     return pos;
 }
 
 std::size_t olm::pickle_length(
-    const olm::Ed25519PublicKey & value
+    const _olm_ed25519_public_key & value
 ) {
     return sizeof(value.public_key);
 }
@@ -143,7 +148,7 @@ std::size_t olm::pickle_length(
 
 std::uint8_t * olm::pickle(
     std::uint8_t * pos,
-    const olm::Ed25519PublicKey & value
+    const _olm_ed25519_public_key & value
 ) {
     pos = olm::pickle_bytes(
         pos, value.public_key, sizeof(value.public_key)
@@ -154,7 +159,7 @@ std::uint8_t * olm::pickle(
 
 std::uint8_t const * olm::unpickle(
     std::uint8_t const * pos, std::uint8_t const * end,
-    olm::Ed25519PublicKey & value
+    _olm_ed25519_public_key & value
 ) {
     pos = olm::unpickle_bytes(
         pos, end, value.public_key, sizeof(value.public_key)
@@ -165,21 +170,24 @@ std::uint8_t const * olm::unpickle(
 
 
 std::size_t olm::pickle_length(
-    const olm::Ed25519KeyPair & value
+    const _olm_ed25519_key_pair & value
 ) {
-    return sizeof(value.public_key) + sizeof(value.private_key);
+    return sizeof(value.public_key.public_key)
+        + sizeof(value.private_key.private_key);
 }
 
 
 std::uint8_t * olm::pickle(
     std::uint8_t * pos,
-    const olm::Ed25519KeyPair & value
+    const _olm_ed25519_key_pair & value
 ) {
     pos = olm::pickle_bytes(
-        pos, value.public_key, sizeof(value.public_key)
+        pos, value.public_key.public_key,
+        sizeof(value.public_key.public_key)
     );
     pos = olm::pickle_bytes(
-        pos, value.private_key, sizeof(value.private_key)
+        pos, value.private_key.private_key,
+        sizeof(value.private_key.private_key)
     );
     return pos;
 }
@@ -187,13 +195,15 @@ std::uint8_t * olm::pickle(
 
 std::uint8_t const * olm::unpickle(
     std::uint8_t const * pos, std::uint8_t const * end,
-    olm::Ed25519KeyPair & value
+    _olm_ed25519_key_pair & value
 ) {
     pos = olm::unpickle_bytes(
-        pos, end, value.public_key, sizeof(value.public_key)
+        pos, end, value.public_key.public_key,
+        sizeof(value.public_key.public_key)
     );
     pos = olm::unpickle_bytes(
-        pos, end, value.private_key, sizeof(value.private_key)
+        pos, end, value.private_key.private_key,
+        sizeof(value.private_key.private_key)
     );
     return pos;
 }
diff --git a/src/ratchet.cpp b/src/ratchet.cpp
index 57cb385..279c4c0 100644
--- a/src/ratchet.cpp
+++ b/src/ratchet.cpp
@@ -41,14 +41,14 @@ static const std::size_t MAX_MESSAGE_GAP = 2000;
  */
 static void create_chain_key(
     olm::SharedKey const & root_key,
-    olm::Curve25519KeyPair const & our_key,
-    olm::Curve25519PublicKey const & their_key,
+    _olm_curve25519_key_pair const & our_key,
+    _olm_curve25519_public_key const & their_key,
     olm::KdfInfo const & info,
     olm::SharedKey & new_root_key,
     olm::ChainKey & new_chain_key
 ) {
     olm::SharedKey secret;
-    olm::curve25519_shared_secret(our_key, their_key, secret);
+    _olm_crypto_curve25519_shared_secret(&our_key, &their_key, secret);
     std::uint8_t derived_secrets[2 * olm::OLM_SHARED_KEY_LENGTH];
     _olm_crypto_hkdf_sha256(
         secret, sizeof(secret),
@@ -189,7 +189,7 @@ olm::Ratchet::Ratchet(
 
 void olm::Ratchet::initialise_as_bob(
     std::uint8_t const * shared_secret, std::size_t shared_secret_length,
-    olm::Curve25519PublicKey const & their_ratchet_key
+    _olm_curve25519_public_key const & their_ratchet_key
 ) {
     std::uint8_t derived_secrets[2 * olm::OLM_SHARED_KEY_LENGTH];
     _olm_crypto_hkdf_sha256(
@@ -210,7 +210,7 @@ void olm::Ratchet::initialise_as_bob(
 
 void olm::Ratchet::initialise_as_alice(
     std::uint8_t const * shared_secret, std::size_t shared_secret_length,
-    olm::Curve25519KeyPair const & our_ratchet_key
+    _olm_curve25519_key_pair const & our_ratchet_key
 ) {
     std::uint8_t derived_secrets[2 * olm::OLM_SHARED_KEY_LENGTH];
     _olm_crypto_hkdf_sha256(
@@ -437,7 +437,7 @@ std::size_t olm::Ratchet::encrypt(
 
     if (sender_chain.empty()) {
         sender_chain.insert();
-        olm::curve25519_generate_key(random, sender_chain[0].ratchet_key);
+        _olm_crypto_curve25519_generate_key(random, &sender_chain[0].ratchet_key);
         create_chain_key(
             root_key,
             sender_chain[0].ratchet_key,
@@ -456,7 +456,8 @@ std::size_t olm::Ratchet::encrypt(
         plaintext_length
     );
     std::uint32_t counter = keys.index;
-    Curve25519PublicKey const & ratchet_key = sender_chain[0].ratchet_key;
+    _olm_curve25519_public_key const & ratchet_key =
+        sender_chain[0].ratchet_key.public_key;
 
     olm::MessageWriter writer;
 
diff --git a/src/session.cpp b/src/session.cpp
index 7bde5d1..72e2be8 100644
--- a/src/session.cpp
+++ b/src/session.cpp
@@ -55,8 +55,8 @@ std::size_t olm::Session::new_outbound_session_random_length() {
 
 std::size_t olm::Session::new_outbound_session(
     olm::Account const & local_account,
-    olm::Curve25519PublicKey const & identity_key,
-    olm::Curve25519PublicKey const & one_time_key,
+    _olm_curve25519_public_key const & identity_key,
+    _olm_curve25519_public_key const & one_time_key,
     std::uint8_t const * random, std::size_t random_length
 ) {
     if (random_length < new_outbound_session_random_length()) {
@@ -64,29 +64,30 @@ std::size_t olm::Session::new_outbound_session(
         return std::size_t(-1);
     }
 
-    olm::Curve25519KeyPair base_key;
-    olm::curve25519_generate_key(random, base_key);
+    _olm_curve25519_key_pair base_key;
+    _olm_crypto_curve25519_generate_key(random, &base_key);
 
-    olm::Curve25519KeyPair ratchet_key;
-    olm::curve25519_generate_key(random + CURVE25519_RANDOM_LENGTH, ratchet_key);
+    _olm_curve25519_key_pair ratchet_key;
+    _olm_crypto_curve25519_generate_key(random + CURVE25519_RANDOM_LENGTH, &ratchet_key);
 
-    olm::Curve25519KeyPair const & alice_identity_key_pair = (
+    _olm_curve25519_key_pair const & alice_identity_key_pair = (
         local_account.identity_keys.curve25519_key
     );
 
     received_message = false;
-    alice_identity_key = alice_identity_key_pair;
-    alice_base_key = base_key;
+    alice_identity_key = alice_identity_key_pair.public_key;
+    alice_base_key = base_key.public_key;
     bob_one_time_key = one_time_key;
 
     // Calculate the shared secret S via triple DH
     std::uint8_t secret[3 * CURVE25519_SHARED_SECRET_LENGTH];
     std::uint8_t * pos = secret;
-    olm::curve25519_shared_secret(alice_identity_key_pair, one_time_key, pos);
+
+    _olm_crypto_curve25519_shared_secret(&alice_identity_key_pair, &one_time_key, pos);
     pos += CURVE25519_SHARED_SECRET_LENGTH;
-    olm::curve25519_shared_secret(base_key, identity_key, pos);
+    _olm_crypto_curve25519_shared_secret(&base_key, &identity_key, pos);
     pos += CURVE25519_SHARED_SECRET_LENGTH;
-    olm::curve25519_shared_secret(base_key, one_time_key, pos);
+    _olm_crypto_curve25519_shared_secret(&base_key, &one_time_key, pos);
 
     ratchet.initialise_as_alice(secret, sizeof(secret), ratchet_key);
 
@@ -120,7 +121,7 @@ static bool check_message_fields(
 
 std::size_t olm::Session::new_inbound_session(
     olm::Account & local_account,
-    olm::Curve25519PublicKey const * their_identity_key,
+    _olm_curve25519_public_key const * their_identity_key,
     std::uint8_t const * one_time_key_message, std::size_t message_length
 ) {
     olm::PreKeyMessageReader reader;
@@ -157,7 +158,7 @@ std::size_t olm::Session::new_inbound_session(
         return std::size_t(-1);
     }
 
-    olm::Curve25519PublicKey ratchet_key;
+    _olm_curve25519_public_key ratchet_key;
     olm::load_array(ratchet_key.public_key, message_reader.ratchet_key);
 
     olm::OneTimeKey const * our_one_time_key = local_account.lookup_key(
@@ -169,19 +170,19 @@ std::size_t olm::Session::new_inbound_session(
         return std::size_t(-1);
     }
 
-    olm::Curve25519KeyPair const & bob_identity_key = (
+    _olm_curve25519_key_pair const & bob_identity_key = (
         local_account.identity_keys.curve25519_key
     );
-    olm::Curve25519KeyPair const & bob_one_time_key = our_one_time_key->key;
+    _olm_curve25519_key_pair const & bob_one_time_key = our_one_time_key->key;
 
     // Calculate the shared secret S via triple DH
     std::uint8_t secret[CURVE25519_SHARED_SECRET_LENGTH * 3];
     std::uint8_t * pos = secret;
-    olm::curve25519_shared_secret(bob_one_time_key, alice_identity_key, pos);
+    _olm_crypto_curve25519_shared_secret(&bob_one_time_key, &alice_identity_key, pos);
     pos += CURVE25519_SHARED_SECRET_LENGTH;
-    olm::curve25519_shared_secret(bob_identity_key, alice_base_key, pos);
+    _olm_crypto_curve25519_shared_secret(&bob_identity_key, &alice_base_key, pos);
     pos += CURVE25519_SHARED_SECRET_LENGTH;
-    olm::curve25519_shared_secret(bob_one_time_key, alice_base_key, pos);
+    _olm_crypto_curve25519_shared_secret(&bob_one_time_key, &alice_base_key, pos);
 
     ratchet.initialise_as_bob(secret, sizeof(secret), ratchet_key);
 
@@ -214,7 +215,7 @@ std::size_t olm::Session::session_id(
 
 
 bool olm::Session::matches_inbound_session(
-    olm::Curve25519PublicKey const * their_identity_key,
+    _olm_curve25519_public_key const * their_identity_key,
     std::uint8_t const * one_time_key_message, std::size_t message_length
 ) {
     olm::PreKeyMessageReader reader;
diff --git a/src/utility.cpp b/src/utility.cpp
index e33351c..43d8e16 100644
--- a/src/utility.cpp
+++ b/src/utility.cpp
@@ -41,7 +41,7 @@ size_t olm::Utility::sha256(
 
 
 size_t olm::Utility::ed25519_verify(
-    Ed25519PublicKey const & key,
+    _olm_ed25519_public_key const & key,
     std::uint8_t const * message, std::size_t message_length,
     std::uint8_t const * signature, std::size_t signature_length
 ) {
@@ -49,7 +49,7 @@ size_t olm::Utility::ed25519_verify(
         last_error = OlmErrorCode::OLM_BAD_MESSAGE_MAC;
         return std::size_t(-1);
     }
-    if (!olm::ed25519_verify(key, message, message_length, signature)) {
+    if (!_olm_crypto_ed25519_verify(&key, message, message_length, signature)) {
         last_error = OlmErrorCode::OLM_BAD_MESSAGE_MAC;
         return std::size_t(-1);
     }