olm/javascript/olm_outbound_group_session.js
David Baker 122867c45c WebAssembly support!
Quite a lot going on in this PR:
 * Updates to support recent emscripten, switching to WASM which is now the default
 * Use emscripten's MODULARIZE option rather than wrapping it ourself, since doing
   so in pre-post js doesn't work anymore.
 * Most changes are moving the emscripten runtime functions to top-level
   calls rather than in the Module object.
 * Get rid of duplicated NULL_BYTE_PADDING_LENGTH
 * Fix ciphertext_length used without being declared
 * Fix things that caused the closure compiler to error, eg. using
   OLM_OPTIONS without a declaration.
 * Wait until module is inited to do OLM_ERROR = olm_error()

The main BREAKING CHANGE here is that the module now needs to initialise
asyncronously (because it has to load the wasm file). require()ing olm
now gives a function which needs to be called to create an instance.
The resulting object has a promise-like then() method that can be used
to detect when the module is ready. (We could use MODULARIZE_INSTANCE
to return the module directly as before, rather than the function,
but then we don't get the .then() method).
2018-09-21 16:01:51 +01:00

129 lines
4.6 KiB
JavaScript

function OutboundGroupSession() {
var size = Module['_olm_outbound_group_session_size']();
this.buf = malloc(size);
this.ptr = Module['_olm_outbound_group_session'](this.buf);
}
function outbound_group_session_method(wrapped) {
return function() {
var result = wrapped.apply(this, arguments);
if (result === OLM_ERROR) {
var message = Pointer_stringify(
Module['_olm_outbound_group_session_last_error'](arguments[0])
);
throw new Error("OLM." + message);
}
return result;
}
}
OutboundGroupSession.prototype['free'] = function() {
Module['_olm_clear_outbound_group_session'](this.ptr);
free(this.ptr);
}
OutboundGroupSession.prototype['pickle'] = restore_stack(function(key) {
var key_array = array_from_string(key);
var pickle_length = outbound_group_session_method(
Module['_olm_pickle_outbound_group_session_length']
)(this.ptr);
var key_buffer = stack(key_array);
var pickle_buffer = stack(pickle_length + NULL_BYTE_PADDING_LENGTH);
outbound_group_session_method(Module['_olm_pickle_outbound_group_session'])(
this.ptr, key_buffer, key_array.length, pickle_buffer, pickle_length
);
return Pointer_stringify(pickle_buffer);
});
OutboundGroupSession.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);
outbound_group_session_method(Module['_olm_unpickle_outbound_group_session'])(
this.ptr, key_buffer, key_array.length, pickle_buffer,
pickle_array.length
);
});
OutboundGroupSession.prototype['create'] = restore_stack(function() {
var random_length = outbound_group_session_method(
Module['_olm_init_outbound_group_session_random_length']
)(this.ptr);
var random = random_stack(random_length);
outbound_group_session_method(Module['_olm_init_outbound_group_session'])(
this.ptr, random, random_length
);
});
OutboundGroupSession.prototype['encrypt'] = function(plaintext) {
var plaintext_buffer, message_buffer, plaintext_length;
try {
plaintext_length = lengthBytesUTF8(plaintext);
var message_length = outbound_group_session_method(
Module['_olm_group_encrypt_message_length']
)(this.ptr, plaintext_length);
// need to allow space for the terminator (which stringToUTF8 always
// writes), hence + 1.
plaintext_buffer = malloc(plaintext_length + 1);
stringToUTF8(plaintext, plaintext_buffer, plaintext_length + 1);
message_buffer = malloc(message_length + NULL_BYTE_PADDING_LENGTH);
outbound_group_session_method(Module['_olm_group_encrypt'])(
this.ptr,
plaintext_buffer, plaintext_length,
message_buffer, message_length
);
// UTF8ToString requires a null-terminated argument, so add the
// null terminator.
setValue(
message_buffer+message_length,
0, "i8"
);
return UTF8ToString(message_buffer);
} finally {
if (plaintext_buffer !== undefined) {
// don't leave a copy of the plaintext in the heap.
bzero(plaintext_buffer, plaintext_length + 1);
free(plaintext_buffer);
}
if (message_buffer !== undefined) {
free(message_buffer);
}
}
};
OutboundGroupSession.prototype['session_id'] = restore_stack(function() {
var length = outbound_group_session_method(
Module['_olm_outbound_group_session_id_length']
)(this.ptr);
var session_id = stack(length + NULL_BYTE_PADDING_LENGTH);
outbound_group_session_method(Module['_olm_outbound_group_session_id'])(
this.ptr, session_id, length
);
return Pointer_stringify(session_id);
});
OutboundGroupSession.prototype['session_key'] = restore_stack(function() {
var key_length = outbound_group_session_method(
Module['_olm_outbound_group_session_key_length']
)(this.ptr);
var key = stack(key_length + NULL_BYTE_PADDING_LENGTH);
outbound_group_session_method(Module['_olm_outbound_group_session_key'])(
this.ptr, key, key_length
);
return Pointer_stringify(key);
});
OutboundGroupSession.prototype['message_index'] = function() {
var idx = outbound_group_session_method(
Module['_olm_outbound_group_session_message_index']
)(this.ptr);
return idx;
};
olm_exports['OutboundGroupSession'] = OutboundGroupSession;