mirrors/core-lightning
1
0
Fork 0
mirror of https://github.com/ElementsProject/lightning.git synced 2025-01-17 19:03:42 +01:00
Code Issues Projects Releases Wiki Activity

sphinx: Fixed a buffer overflow in hmac generation

Browse Source 
Our HMACs are truncated to 20 byte, but sodium still generates 32 byte
HMACs and we were handing in a buffer that was too small, so we
overflowing the buffer by 12 bytes. This manifested itself only in the
32 bit variant because of different alignment in the 64bit version.

Fixes #94.

Signed-off-by: Christian Decker <decker.christian@gmail.com>
This commit is contained in:
Christian Decker 2016-11-16 14:27:27 +01:00
parent 34b4134cb0
commit 188b3c3e19
No known key found for this signature in database
GPG Key ID: 1416D83DC4F0E86D
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
daemon/sphinx.c
View File

@ -184,11 +184,13 @@ static bool compute_hmac(
static void compute_packet_hmac(struct onionpacket *packet, u8 *mukey, u8 *hmac)
{
u8 mactemp[ROUTING_INFO_SIZE + TOTAL_HOP_PAYLOAD_SIZE + MESSAGE_SIZE];
u8 mac[32];
memcpy(mactemp, packet->routinginfo, ROUTING_INFO_SIZE);
memcpy(mactemp + ROUTING_INFO_SIZE, packet->hoppayloads, TOTAL_HOP_PAYLOAD_SIZE);
memcpy(mactemp + ROUTING_INFO_SIZE + TOTAL_HOP_PAYLOAD_SIZE, packet->payload, sizeof(packet->payload));
compute_hmac(hmac, mactemp, sizeof(mactemp), mukey, KEY_LEN);
compute_hmac(mac, mactemp, sizeof(mactemp), mukey, KEY_LEN);
memcpy(hmac, mac, 20);
}
static bool generate_key(void *k, const char *t, u8 tlen, const u8 *s)