Add javascript bindings using emscripten

1 files changed, 247 insertions, 0 deletions

diff --git a/javascript/axolotl_post.js b/javascript/axolotl_post.js
new file mode 100644
index 0000000..7902725
--- /dev/null
+++ b/javascript/axolotl_post.js
@@ -0,0 +1,247 @@
+var runtime = Module['Runtime'];
+var malloc = Module['_malloc'];
+var free = Module['_free'];
+var Pointer_stringify = Module['Pointer_stringify'];
+var AXOLOTL_ERROR = Module['_axolotl_error']();
+
+function stack(size_or_array) {
+    return Module['allocate'](size_or_array, 'i8', Module['ALLOC_STACK']);
+}
+
+function array_from_string(string) {
+    return Module['intArrayFromString'](string, true);
+}
+
+function random_stack(size) {
+    var ptr = stack(size);
+    var array = new Uint8Array(Module['HEAPU8'].buffer, ptr, size);
+    window.crypto.getRandomValues(array);
+}
+
+function restore_stack(wrapped) {
+    return function() {
+        var sp = runtime.stackSave();
+        try {
+            return wrapped.apply(this, arguments);
+        } finally {
+            runtime.stackRestore(sp);
+        }
+    }
+}
+
+function Account() {
+    var size = Module['_axolotl_account_size']();
+    this.buf = malloc(size);
+    this.ptr = Module['_axolotl_account'](this.buf);
+}
+
+function account_method(wrapped) {
+    return function() {
+        var result = wrapped.apply(this, arguments);
+        if (result === AXOLOTL_ERROR) {
+            var message = Pointer_stringify(
+                Module['_axolotl_account_last_error'](arguments[0])
+            );
+            throw "AXOLOTL." + message;
+        }
+        return result;
+    }
+}
+
+Account.prototype['free'] = function() {
+    free(this.ptr);
+}
+
+Account.prototype['create'] = restore_stack(function() {
+    var random_length = account_method(
+        Module['_axolotl_create_account_random_length']
+    )(this.ptr);
+    var random = random_stack(random_length);
+    account_method(Module['_axolotl_create_account'])(
+        this.ptr, random, random_length
+    );
+});
+
+Account.prototype['identity_keys'] = restore_stack(function() {
+    var keys_length = account_method(
+        Module['_axolotl_account_identity_keys_length']
+    )(this.ptr);
+    var keys = stack(keys_length);
+    account_method(Module['_axolotl_account_identity_keys'])(
+        this.ptr, keys, keys_length
+    );
+    return Pointer_stringify(keys, keys_length);
+});
+
+Account.prototype['one_time_keys'] = restore_stack(function() {
+    var keys_length = account_method(
+        Module['_axolotl_account_one_time_keys_length']
+    )(this.ptr);
+    var keys = stack(keys_length);
+    account_method(Module['_axolotl_account_one_time_keys'])(
+        this.ptr, keys, keys_length
+    );
+    return Pointer_stringify(keys, keys_length);
+});
+
+Account.prototype['pickle'] = restore_stack(function(key) {
+    var key_array = array_from_string(key);
+    var pickle_length = account_method(
+        Module['_axolotl_pickle_account_length']
+    )(this.ptr);
+    var key_buffer = stack(key_array);
+    var pickle_buffer = stack(pickle_length);
+    account_method(Module['_axolotl_pickle_account'])(
+        this.ptr, key_buffer, key_array.length, pickle_buffer, pickle_length
+    );
+    return Pointer_stringify(pickle_buffer, pickle_length);
+});
+
+Account.prototype['unpickle'] = restore_stack(function(key, pickle) {
+    var key_array = array_from_string(key);
+    var key_buffer = stack(key_array);
+    var pickle_array = array_from_string(pickle);
+    var pickle_buffer = stack(pickle_length);
+    account_method(Module['_axolotl_unpickle_account'])(
+        this.ptr, key_buffer, key_array.length, pickle_buffer,
+        pickle_array.length
+    );
+});
+
+function Session() {
+    var size = Module['_axolotl_session_size']();
+    this.buf = malloc(size);
+    this.ptr = Module['_axolotl_session'](this.buf);
+}
+
+function session_method(wrapped) {
+    return function() {
+        var result = wrapped.apply(this, arguments);
+        if (result === AXOLOTL_ERROR) {
+            var message = Pointer_stringify(
+                Module['_axolotl_session_last_error'](arguments[0])
+            );
+            throw "AXOLOTL." + message;
+        }
+        return result;
+    }
+}
+
+Session.prototype['free'] = function() {
+    free(this.ptr);
+}
+
+Session.prototype['pickle'] = restore_stack(function(key) {
+    var key_array = array_from_string(key);
+    var pickle_length = session_method(
+        Module['_axolotl_pickle_session_length']
+    )(this.ptr);
+    var key_buffer = stack(key_array);
+    var pickle_buffer = stack(pickle_length);
+    session_method(Module['_axolotl_pickle_session'])(
+        this.ptr, key_buffer, key_array.length, pickle_buffer, pickle_length
+    );
+    return Pointer_stringify(pickle_buffer, pickle_length);
+});
+
+Session.prototype['unpickle'] = restore_stack(function(key, pickle) {
+    var key_array = array_from_string(key);
+    var key_buffer = stack(key_array);
+    var pickle_array = array_from_string(pickle);
+    var pickle_buffer = stack(pickle_array);
+    session_method(Module['_axolotl_unpickle_session'])(
+        this.ptr, key_buffer, key_array.length, pickle_buffer,
+        pickle_array.length
+    );
+});
+
+Session.prototype['create_outbound'] = restore_stack(function(
+    account, their_identity_key, their_one_time_key_id, their_one_time_key
+) {
+    var random_length = session_method(
+        Module['_axolotl_create_outbound_session_random_length']
+    )(this.ptr);
+    var random = random_stack(random_length);
+    var identity_key_array = array_from_string(their_identity_key);
+    var one_time_key_array = array_from_string(their_one_time_key);
+    var identity_key_buffer = stack(identity_key_array);
+    var one_time_key_buffer = stack(one_time_key_array);
+    session_method(Module['_axolotl_create_outbound_session'])(
+        this.ptr, account.ptr,
+        identity_key_buffer, identity_key_array.length,
+        their_one_time_key_id,
+        one_time_key_buffer, one_time_key_array.length,
+        random, random_length
+    );
+});
+
+Session.prototype['create_inbound'] = restore_stack(function(
+    account, one_time_key_message
+) {
+    var message_array = array_from_string(one_time_key_message);
+    var message_buffer = stack(message_array);
+    session_method(Module['_axolotl_create_inbound_session'])(
+        this.ptr, account.ptr, message_buffer, message_array.length
+    );
+});
+
+Session.prototype['matches_inbound'] = restore_stack(function(
+    account, one_time_key_message
+) {
+    var message_array = array_from_string(one_time_key_message);
+    var message_buffer = stack(message_array);
+    return session_method(Module['_axolotl_matches_inbound_session'])(
+        this.ptr, account.ptr, message_buffer, message_array.length
+    ) ? true : false;
+});
+
+Session.prototype['encrypt'] = restore_stack(function(
+    plaintext
+) {
+    var random_length = session_method(
+        Module['_axolotl_encrypt_random_length']
+    )(this.ptr);
+    var message_type = session_method(
+        Module['_axolotl_encrypt_message_type']
+    )(this.ptr);
+    var plaintext_array = array_from_string(plaintext);
+    var message_length = session_method(
+        Module['_axolotl_encrypt_message_length']
+    )(this.ptr, plaintext_array.length);
+    var random = random_stack(random_length);
+    var plaintext_buffer = stack(plaintext_array);
+    var message_buffer = stack(message_length);
+    session_method(Module['_axolotl_encrypt'])(
+        this.ptr,
+        plaintext_buffer, plaintext_array.length,
+        random, random_length,
+        message_buffer, message_length
+    );
+    return {
+        "type": message_type,
+        "body": Pointer_stringify(message_buffer, message_length)
+    };
+});
+
+Session.prototype['decrypt'] = restore_stack(function(
+    message_type, message
+) {
+    var message_array = array_from_string(message);
+    var message_buffer = stack(message_array);
+    var max_plaintext_length = session_method(
+        Module['_axolotl_decrypt_max_plaintext_length']
+    )(this.ptr, message_type, message_buffer, message_array.length);
+    // caculating the length destroys the input buffer.
+    // So we copy the array to a new buffer
+    var message_buffer = stack(message_array);
+    var plaintext_buffer = stack(max_plaintext_length);
+    var plaintext_length = session_method(Module["_axolotl_decrypt"])(
+        this.ptr, message_type,
+        message_buffer, message.length,
+        plaintext_buffer, max_plaintext_length
+    );
+    return Pointer_stringify(plaintext_buffer, plaintext_length);
+});
+
+return {"Account": Account, "Session": Session};
+}();