- djm@cvs.openbsd.org 2007/06/05 06:52:37

     [kex.c monitor_wrap.c packet.c mac.h kex.h mac.c]
     Preserve MAC ctx between packets, saving 2xhash calls per-packet.
     Yields around a 12-16% end-to-end speedup for arcfour256/hmac-md5
     patch from markus@ tested dtucker@ and myself, ok markus@ and me (I'm
     committing at his request)

7 files changed, 49 insertions, 25 deletions

diff --git a/ChangeLog b/ChangeLog
index f0668460..c5c0c9dd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -18,6 +18,12 @@
    - djm@cvs.openbsd.org 2007/06/02 09:04:58
      [bufbn.c]
      memory leak on error path; from arnaud.lacombe.1 AT ulaval.ca
+   - djm@cvs.openbsd.org 2007/06/05 06:52:37
+     [kex.c monitor_wrap.c packet.c mac.h kex.h mac.c]
+     Preserve MAC ctx between packets, saving 2xhash calls per-packet.
+     Yields around a 12-16% end-to-end speedup for arcfour256/hmac-md5
+     patch from markus@ tested dtucker@ and myself, ok markus@ and me (I'm
+     committing at his request)
 
 20070520
  - (dtucker) OpenBSD CVS Sync
@@ -2961,4 +2967,4 @@
    OpenServer 6 and add osr5bigcrypt support so when someone migrates
    passwords between UnixWare and OpenServer they will still work. OK dtucker@
 
-$Id: ChangeLog,v 1.4675 2007/06/05 08:29:35 dtucker Exp $
+$Id: ChangeLog,v 1.4676 2007/06/05 08:30:18 dtucker Exp $
diff --git a/kex.c b/kex.c
index ad2e93cc..332fadf6 100644
--- a/kex.c
+++ b/kex.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.c,v 1.78 2007/05/30 05:58:13 djm Exp $ */
+/* $OpenBSD: kex.c,v 1.79 2007/06/05 06:52:37 djm Exp $ */
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  *
@@ -279,7 +279,7 @@ choose_mac(Mac *mac, char *client, char *server)
 	if (name == NULL)
 		fatal("no matching mac found: client %s server %s",
 		    client, server);
-	if (mac_init(mac, name) < 0)
+	if (mac_setup(mac, name) < 0)
 		fatal("unsupported mac %s", name);
 	/* truncate the key */
 	if (datafellows & SSH_BUG_HMAC)
diff --git a/kex.h b/kex.h
index b1b20f50..ecf43130 100644
--- a/kex.h
+++ b/kex.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.h,v 1.44 2006/08/03 03:34:42 deraadt Exp $ */
+/* $OpenBSD: kex.h,v 1.45 2007/06/05 06:52:37 djm Exp $ */
 
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
@@ -28,6 +28,7 @@
 
 #include <signal.h>
 #include <openssl/evp.h>
+#include <openssl/hmac.h>
 
 #define	KEX_DH1			"diffie-hellman-group1-sha1"
 #define	KEX_DH14		"diffie-hellman-group14-sha1"
@@ -90,6 +91,7 @@ struct Mac {
 	u_int	mac_len;
 	u_char	*key;
 	u_int	key_len;
+	HMAC_CTX	ctx;
 };
 struct Comp {
 	int	type;
diff --git a/mac.c b/mac.c
index e5d5bfa8..6a5fd476 100644
--- a/mac.c
+++ b/mac.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: mac.c,v 1.12 2006/08/03 03:34:42 deraadt Exp $ */
+/* $OpenBSD: mac.c,v 1.13 2007/06/05 06:52:37 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -57,7 +57,7 @@ struct {
 };
 
 int
-mac_init(Mac *mac, char *name)
+mac_setup(Mac *mac, char *name)
 {
 	int i, evp_len;
 
@@ -71,34 +71,44 @@ mac_init(Mac *mac, char *name)
 				if (macs[i].truncatebits != 0)
 					mac->mac_len = macs[i].truncatebits/8;
 			}
-			debug2("mac_init: found %s", name);
+			debug2("mac_setup: found %s", name);
 			return (0);
 		}
 	}
-	debug2("mac_init: unknown %s", name);
+	debug2("mac_setup: unknown %s", name);
 	return (-1);
 }
 
+void
+mac_init(Mac *mac)
+{
+	if (mac->key == NULL)
+		fatal("mac_init: no key");
+	HMAC_Init(&mac->ctx, mac->key, mac->key_len, mac->md);
+}
+
 u_char *
 mac_compute(Mac *mac, u_int32_t seqno, u_char *data, int datalen)
 {
-	HMAC_CTX c;
 	static u_char m[EVP_MAX_MD_SIZE];
 	u_char b[4];
 
-	if (mac->key == NULL)
-		fatal("mac_compute: no key");
 	if (mac->mac_len > sizeof(m))
 		fatal("mac_compute: mac too long");
-	HMAC_Init(&c, mac->key, mac->key_len, mac->md);
 	put_u32(b, seqno);
-	HMAC_Update(&c, b, sizeof(b));
-	HMAC_Update(&c, data, datalen);
-	HMAC_Final(&c, m, NULL);
-	HMAC_cleanup(&c);
+	HMAC_Init(&mac->ctx, NULL, 0, NULL);	/* reset HMAC context */
+	HMAC_Update(&mac->ctx, b, sizeof(b));
+	HMAC_Update(&mac->ctx, data, datalen);
+	HMAC_Final(&mac->ctx, m, NULL);
 	return (m);
 }
 
+void
+mac_clear(Mac *mac)
+{
+	HMAC_cleanup(&mac->ctx);
+}
+
 /* XXX copied from ciphers_valid */
 #define	MAC_SEP	","
 int
@@ -111,7 +121,7 @@ mac_valid(const char *names)
 	maclist = cp = xstrdup(names);
 	for ((p = strsep(&cp, MAC_SEP)); p && *p != '\0';
 	    (p = strsep(&cp, MAC_SEP))) {
-		if (mac_init(NULL, p) < 0) {
+		if (mac_setup(NULL, p) < 0) {
 			debug("bad mac %s [%s]", p, names);
 			xfree(maclist);
 			return (0);
diff --git a/mac.h b/mac.h
index 960cc5c5..2010c9d3 100644
--- a/mac.h
+++ b/mac.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: mac.h,v 1.4 2006/03/25 22:22:43 djm Exp $ */
+/* $OpenBSD: mac.h,v 1.5 2007/06/05 06:52:37 djm Exp $ */
 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
@@ -24,5 +24,7 @@
  */
 
 int	 mac_valid(const char *);
-int	 mac_init(Mac *, char *);
+int	 mac_setup(Mac *, char *);
+void	 mac_init(Mac *);
 u_char	*mac_compute(Mac *, u_int32_t, u_char *, int);
+void	 mac_clear(Mac *);
diff --git a/monitor_wrap.c b/monitor_wrap.c
index 27cc1c5f..61f7c688 100644
--- a/monitor_wrap.c
+++ b/monitor_wrap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor_wrap.c,v 1.55 2007/02/19 10:45:58 dtucker Exp $ */
+/* $OpenBSD: monitor_wrap.c,v 1.56 2007/06/05 06:52:37 djm Exp $ */
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * Copyright 2002 Markus Friedl <markus@openbsd.org>
@@ -476,7 +476,7 @@ mm_newkeys_from_blob(u_char *blob, int blen)
 
 	/* Mac structure */
 	mac->name = buffer_get_string(&b, NULL);
-	if (mac->name == NULL || mac_init(mac, mac->name) == -1)
+	if (mac->name == NULL || mac_setup(mac, mac->name) == -1)
 		fatal("%s: can not init mac %s", __func__, mac->name);
 	mac->enabled = buffer_get_int(&b);
 	mac->key = buffer_get_string(&b, &len);
diff --git a/packet.c b/packet.c
index a2e9f598..27489801 100644
--- a/packet.c
+++ b/packet.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: packet.c,v 1.146 2007/05/31 23:34:29 djm Exp $ */
+/* $OpenBSD: packet.c,v 1.147 2007/06/05 06:52:37 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -629,7 +629,8 @@ set_newkeys(int mode)
 		enc  = &newkeys[mode]->enc;
 		mac  = &newkeys[mode]->mac;
 		comp = &newkeys[mode]->comp;
-		memset(mac->key, 0, mac->key_len);
+		if (mac->md != NULL)
+			mac_clear(mac);
 		xfree(enc->name);
 		xfree(enc->iv);
 		xfree(enc->key);
@@ -644,14 +645,17 @@ set_newkeys(int mode)
 	enc  = &newkeys[mode]->enc;
 	mac  = &newkeys[mode]->mac;
 	comp = &newkeys[mode]->comp;
-	if (mac->md != NULL)
+	if (mac->md != NULL) {
+		mac_init(mac);
 		mac->enabled = 1;
+	}
 	DBG(debug("cipher_init_context: %d", mode));
 	cipher_init(cc, enc->cipher, enc->key, enc->key_len,
 	    enc->iv, enc->block_size, crypt_type);
 	/* Deleting the keys does not gain extra security */
 	/* memset(enc->iv,  0, enc->block_size);
-	   memset(enc->key, 0, enc->key_len); */
+	   memset(enc->key, 0, enc->key_len);
+	   memset(mac->key, 0, mac->key_len); */
 	if ((comp->type == COMP_ZLIB ||
 	    (comp->type == COMP_DELAYED && after_authentication)) &&
 	    comp->enabled == 0) {