From 12555a2d97e5784eeb105ca9b1b533d4c95f1115 Mon Sep 17 00:00:00 2001 From: Todd Malsbary Date: Tue, 19 May 2020 09:45:34 -0700 Subject: mptcp: use rightmost 64 bits in ADD_ADDR HMAC This changes the HMAC used in the ADD_ADDR option from the leftmost 64 bits to the rightmost 64 bits as described in RFC 8684, section 3.4.1. This issue was discovered while adding support to packetdrill for the ADD_ADDR v1 option. Fixes: 3df523ab582c ("mptcp: Add ADD_ADDR handling") Signed-off-by: Todd Malsbary Acked-by: Christoph Paasch Reviewed-by: Matthieu Baerts Signed-off-by: David S. Miller --- net/mptcp/options.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/mptcp/options.c') diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 45497af23906..b88fae233a62 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -545,7 +545,7 @@ static u64 add_addr_generate_hmac(u64 key1, u64 key2, u8 addr_id, mptcp_crypto_hmac_sha(key1, key2, msg, 7, hmac); - return get_unaligned_be64(hmac); + return get_unaligned_be64(&hmac[MPTCP_ADDR_HMAC_LEN - sizeof(u64)]); } #if IS_ENABLED(CONFIG_MPTCP_IPV6) @@ -562,7 +562,7 @@ static u64 add_addr6_generate_hmac(u64 key1, u64 key2, u8 addr_id, mptcp_crypto_hmac_sha(key1, key2, msg, 19, hmac); - return get_unaligned_be64(hmac); + return get_unaligned_be64(&hmac[MPTCP_ADDR_HMAC_LEN - sizeof(u64)]); } #endif -- cgit v1.2.3-70-g09d2