From 653790eacbf7dcf94cbf181657cdb0c30c890c3f Mon Sep 17 00:00:00 2001 From: Mark Haines Date: Thu, 20 Oct 2016 09:58:55 +0100 Subject: Return the message index when decrypting group messages. Applications can use the index to detect replays of the same message. --- src/inbound_group_session.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) (limited to 'src/inbound_group_session.c') diff --git a/src/inbound_group_session.c b/src/inbound_group_session.c index bf00008..ed313a0 100644 --- a/src/inbound_group_session.c +++ b/src/inbound_group_session.c @@ -263,7 +263,8 @@ size_t olm_group_decrypt_max_plaintext_length( static size_t _decrypt( OlmInboundGroupSession *session, uint8_t * message, size_t message_length, - uint8_t * plaintext, size_t max_plaintext_length + uint8_t * plaintext, size_t max_plaintext_length, + uint32_t * message_index ) { struct _OlmDecodeGroupMessageResults decoded_results; size_t max_length, r; @@ -286,6 +287,8 @@ static size_t _decrypt( return (size_t)-1; } + *message_index = decoded_results.message_index; + /* verify the signature. We could do this before decoding the message, but * we allow for the possibility of future protocol versions which use a * different signing mechanism; we would rather throw "BAD_MESSAGE_VERSION" @@ -349,7 +352,8 @@ static size_t _decrypt( size_t olm_group_decrypt( OlmInboundGroupSession *session, uint8_t * message, size_t message_length, - uint8_t * plaintext, size_t max_plaintext_length + uint8_t * plaintext, size_t max_plaintext_length, + uint32_t * message_index ) { size_t raw_message_length; @@ -361,7 +365,8 @@ size_t olm_group_decrypt( return _decrypt( session, message, raw_message_length, - plaintext, max_plaintext_length + plaintext, max_plaintext_length, + message_index ); } -- cgit v1.2.3