Merge pull request #16 from matrix-org/rav/fix_megolm_utf8

Fix megolm decryption of UTF-8
This commit is contained in:
Richard van der Hoff 2016-09-05 10:37:55 +01:00 committed by GitHub
commit fee1748c60
3 changed files with 33 additions and 13 deletions

View file

@ -1,3 +1,9 @@
/* The 'length' argument to Pointer_stringify doesn't work if the input includes
* characters >= 128; we therefore need to add a NULL character to all of our
* strings. This acts as a symbolic constant to help show what we're doing.
*/
var NULL_BYTE_PADDING_LENGTH = 1;
function InboundGroupSession() {
var size = Module['_olm_inbound_group_session_size']();
this.buf = malloc(size);
@ -28,11 +34,11 @@ InboundGroupSession.prototype['pickle'] = restore_stack(function(key) {
Module['_olm_pickle_inbound_group_session_length']
)(this.ptr);
var key_buffer = stack(key_array);
var pickle_buffer = stack(pickle_length);
var pickle_buffer = stack(pickle_length + NULL_BYTE_PADDING_LENGTH);
inbound_group_session_method(Module['_olm_pickle_inbound_group_session'])(
this.ptr, key_buffer, key_array.length, pickle_buffer, pickle_length
);
return Pointer_stringify(pickle_buffer, pickle_length);
return Pointer_stringify(pickle_buffer);
});
InboundGroupSession.prototype['unpickle'] = restore_stack(function(key, pickle) {
@ -66,13 +72,21 @@ InboundGroupSession.prototype['decrypt'] = restore_stack(function(
// 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_buffer = stack(max_plaintext_length + NULL_BYTE_PADDING_LENGTH);
var plaintext_length = session_method(Module["_olm_group_decrypt"])(
this.ptr,
message_buffer, message_array.length,
plaintext_buffer, max_plaintext_length
);
return Pointer_stringify(plaintext_buffer, plaintext_length);
// Pointer_stringify requires a null-terminated argument (the optional
// 'len' argument doesn't work for UTF-8 data).
Module['setValue'](
plaintext_buffer+plaintext_length,
0, "i8"
);
return Pointer_stringify(plaintext_buffer);
});
olm_exports['InboundGroupSession'] = InboundGroupSession;

View file

@ -1,3 +1,9 @@
/* The 'length' argument to Pointer_stringify doesn't work if the input includes
* characters >= 128; we therefore need to add a NULL character to all of our
* strings. This acts as a symbolic constant to help show what we're doing.
*/
var NULL_BYTE_PADDING_LENGTH = 1;
function OutboundGroupSession() {
var size = Module['_olm_outbound_group_session_size']();
@ -29,11 +35,11 @@ OutboundGroupSession.prototype['pickle'] = restore_stack(function(key) {
Module['_olm_pickle_outbound_group_session_length']
)(this.ptr);
var key_buffer = stack(key_array);
var pickle_buffer = stack(pickle_length);
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, pickle_length);
return Pointer_stringify(pickle_buffer);
});
OutboundGroupSession.prototype['unpickle'] = restore_stack(function(key, pickle) {
@ -63,35 +69,35 @@ OutboundGroupSession.prototype['encrypt'] = restore_stack(function(plaintext) {
Module['_olm_group_encrypt_message_length']
)(this.ptr, plaintext_array.length);
var plaintext_buffer = stack(plaintext_array);
var message_buffer = stack(message_length);
var message_buffer = stack(message_length + NULL_BYTE_PADDING_LENGTH);
outbound_group_session_method(Module['_olm_group_encrypt'])(
this.ptr,
plaintext_buffer, plaintext_array.length,
message_buffer, message_length
);
return Pointer_stringify(message_buffer, message_length);
return Pointer_stringify(message_buffer);
});
OutboundGroupSession.prototype['session_id'] = restore_stack(function(key) {
var length = outbound_group_session_method(
Module['_olm_outbound_group_session_id_length']
)(this.ptr);
var session_id = stack(length);
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, length);
return Pointer_stringify(session_id);
});
OutboundGroupSession.prototype['session_key'] = restore_stack(function(key) {
var key_length = outbound_group_session_method(
Module['_olm_outbound_group_session_key_length']
)(this.ptr);
var key = stack(key_length);
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, key_length);
return Pointer_stringify(key);
});
OutboundGroupSession.prototype['message_index'] = function() {

View file

@ -5,7 +5,7 @@ var Pointer_stringify = Module['Pointer_stringify'];
var OLM_ERROR = Module['_olm_error']();
/* The 'length' argument to Pointer_stringify doesn't work if the input includes
* cahracters >= 128; we therefore need to add a NULL character to all of our
* characters >= 128; we therefore need to add a NULL character to all of our
* strings. This acts as a symbolic constant to help show what we're doing.
*/
var NULL_BYTE_PADDING_LENGTH = 1;