From 6886c5f57ceb4db04c2e4e4a3d52da1d233698dc Mon Sep 17 00:00:00 2001
From: Linus Nordberg <linus@nordu.net>
Date: Tue, 5 Apr 2011 15:53:58 +0200
Subject: Hash full MAC even for VendorHashed and VendorKeyHashed.

Comment on VendorKeyHashed, from source:
We are hashing the first nine octets too for easier correlation
between vendor-key-hashed and fully-key-hashed log records.  This
opens up for a known plaintext attack on the key but the consequences
of that is considered outweighed by the convenience gained.
---
 fticks.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/fticks.c b/fticks.c
index f882854..d4d405b 100644
--- a/fticks.c
+++ b/fticks.c
@@ -183,11 +183,17 @@ fticks_log(const struct options *options,
 		break;
 	    case RSP_FTICKS_MAC_VENDOR_HASHED:
 		memcpy(macout, macin, 9);
-		fticks_hashmac(macin + 9, NULL, sizeof(macout) - 9, macout + 9);
+		fticks_hashmac(macin, NULL, sizeof(macout) - 9, macout + 9);
 		break;
 	    case RSP_FTICKS_MAC_VENDOR_KEY_HASHED:
 		memcpy(macout, macin, 9);
-		fticks_hashmac(macin + 9, options->fticks_key,
+		/* We are hashing the first nine octets too for easier
+		 * correlation between vendor-key-hashed and
+		 * fully-key-hashed log records.  This opens up for a
+		 * known plaintext attack on the key but the
+		 * consequences of that is considered outweighed by
+		 * the convenience gained.  */
+		fticks_hashmac(macin, options->fticks_key,
 			       sizeof(macout) - 9, macout + 9);
 		break;
 	    case RSP_FTICKS_MAC_FULLY_HASHED:
-- 
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