svn commit: r325872 - head/sys/netipsec

[Conrad Meyer]

Author: cem
Date: Wed Nov 15 22:42:20 2017
New Revision: 325872
URL: https://svnweb.freebsd.org/changeset/base/325872

Log:
  ipsec: Use the same keysize values for HMAC as prior to r324017
  
  The HMAC construction natively permits any key size between 0 and the input
  block length. Before r324017, the auth_hash 'keysize' member was the hash
  output length, which was used by ipsec for key sizes. (Non-ipsec consumers
  need the ability to use other keysizes, hence, r324017.)
  
  The ipsec SADB code blindly uses the auth_hash 'keysize' member for both
  minimum and maximum key size, which is wrong (from an HMAC perspective).
  For now, just switch it to 'hashsize', which matches the existing
  expectations.
  
  Instead it should probably use the range [0, keysize]. But there may be
  other broken code in ipsec that rejects hashes with too small a minimum
  key size.
  
  Reported by:	olivier@
  Reviewed by:	olivier, no objection from ae
  Sponsored by:	Dell EMC Isilon
  Differential Revision:	https://reviews.freebsd.org/D12770

Modified:
  head/sys/netipsec/key.c

Modified: head/sys/netipsec/key.c
==============================================================================
--- head/sys/netipsec/key.c	Wed Nov 15 22:40:46 2017	(r325871)
+++ head/sys/netipsec/key.c	Wed Nov 15 22:42:20 2017	(r325872)
@@ -6263,7 +6263,7 @@ key_getsizes_ah(const struct auth_hash *ah, int alg, u
     u_int16_t* max)
 {
 
-	*min = *max = ah->keysize;
+	*min = *max = ah->hashsize;
 	if (ah->keysize == 0) {
 		/*
 		 * Transform takes arbitrary key size but algorithm