Instead of polling the carp interface to detect a switch between MASTER and

BACKUP, listen to the routing socket for link change messages.

Based on a diff from nathanael at polymorpheous dot com.

ok moritz@

6 files changed, 116 insertions, 91 deletions

diff --git a/usr.sbin/sasyncd/carp.c b/usr.sbin/sasyncd/carp.c
index dee7e4451b5..918328dc51e 100644
--- a/usr.sbin/sasyncd/carp.c
+++ b/usr.sbin/sasyncd/carp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: carp.c,v 1.2 2006/01/26 09:53:46 moritz Exp $	*/
+/*	$OpenBSD: carp.c,v 1.3 2006/06/01 22:43:12 mcbride Exp $	*/
 
 /*
  * Copyright (c) 2005 Håkan Olsson.  All rights reserved.
@@ -34,7 +34,7 @@
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <net/if.h>
-#include <netinet/ip_carp.h>
+#include <net/route.h>
 
 #include <errno.h>
 #include <stdio.h>
@@ -43,19 +43,33 @@
 
 #include "sasyncd.h"
 
-/* For some reason, ip_carp.h does not define this.  */
-#define CARP_INIT	0
-#define CARP_BACKUP	1
-#define CARP_MASTER	2
+static enum RUNSTATE
+carp_map_state(u_char link_state)
+{
+	enum RUNSTATE state = FAIL;
+
+	switch(link_state) {
+	case LINK_STATE_UP:
+		state = MASTER;
+		break;
+	case LINK_STATE_DOWN:
+		state = SLAVE;
+		break;
+	case LINK_STATE_UNKNOWN:
+		state = INIT;
+		break;
+	}
+
+	return state;
+}
 
 /* Returns 1 for the CARP MASTER, 0 for BACKUP/INIT, -1 on error.  */
 static enum RUNSTATE
 carp_get_state(char *ifname)
 {
 	struct ifreq	ifr;
-	struct carpreq	carp;
+	struct if_data	ifrdat;
 	int		s, saved_errno;
-	char		*state;
 
 	if (!ifname || !*ifname) {
 		errno = ENOENT;
@@ -69,58 +83,40 @@ carp_get_state(char *ifname)
 	if (s < 0)
 		return FAIL;
 
-	ifr.ifr_data = (caddr_t)&carp;
-	if (ioctl(s, SIOCGVH, (caddr_t)&ifr) == -1) {
+	ifr.ifr_data = (caddr_t)&ifrdat;
+	if (ioctl(s, SIOCGIFDATA, (caddr_t)&ifr) == -1) {
 		saved_errno = errno;
 		close(s);
 		errno = saved_errno;
 		return FAIL;
 	}
 	close(s);
+	return carp_map_state(ifrdat.ifi_link_state);
+}
 
-	switch (carp.carpr_state) {
-	case CARP_INIT:
-		state = "INIT";
-		break;
-
-	case CARP_BACKUP:
-		state = "BACKUP";
-		break;
-
-	case CARP_MASTER:
-		state = "MASTER";
-		break;
-
-	default:
-		state = "<unknown>";
-		break;
-	}
-
-	log_msg(4, "carp_get_state: %s vhid %d state %s(%d)", ifname,
-	    carp.carpr_vhid, state, carp.carpr_state);
+const char*
+carp_state_name(enum RUNSTATE state)
+{
+	static const char	*carpstate[] = CARPSTATES;
 
-	if (carp.carpr_vhid > 0)
-		return carp.carpr_state == CARP_MASTER ? MASTER : SLAVE;
-	else
-		return FAIL;
+	if (state < 0 || state > FAIL)
+		state = FAIL;
+	return carpstate[state];
 }
 
 void
-carp_check_state(void)
+carp_update_state(enum RUNSTATE current_state)
 {
-	enum RUNSTATE	current_state = carp_get_state(cfgstate.carp_ifname);
-	static char	*carpstate[] = CARPSTATES;
 
 	if (current_state < 0 || current_state > FAIL) {
-		log_err("carp_state_tracker: invalid result on interface "
-		    "%s, abort", cfgstate.carp_ifname);
+		log_err("carp_update_state: invalid carp state, abort");
 		cfgstate.runstate = FAIL;
 		return;
 	}
 
 	if (current_state != cfgstate.runstate) {
-		log_msg(1, "carp_state_tracker: switching state to %s",
-		    carpstate[current_state]);
+		log_msg(1, "carp_update_state: switching state to %s",
+		    carp_state_name(current_state));
 		cfgstate.runstate = current_state;
 		if (current_state == MASTER)
 			pfkey_set_promisc();
@@ -128,49 +124,81 @@ carp_check_state(void)
 	}
 }
 
-static void
-carp_state_tracker(void *v_arg)
+void
+carp_check_state()
 {
-	static int	failures = 0;
-	u_int32_t	next_check;
+	carp_update_state(carp_get_state(cfgstate.carp_ifname));
+}
 
-	carp_check_state();
+void
+carp_set_rfd(fd_set *fds)
+{
+	if (cfgstate.route_socket != -1)
+		FD_SET(cfgstate.route_socket, fds);
+}
 
-	if (cfgstate.runstate == FAIL)
-		if (++failures < 3)
-			log_err("carp_state_tracker");
+static void
+carp_read(void)
+{
+	char msg[2048];
+	struct if_msghdr *ifm = (struct if_msghdr *)&msg;
+	int len;
 
-	if (failures > 5)
-		next_check = 600;
-	else
-		next_check = cfgstate.carp_check_interval + failures * 10;
+	len = read(cfgstate.route_socket, msg, sizeof(msg));
 
-	if (timer_add("carp_state_tracker", next_check, carp_state_tracker,
-	    NULL))
-		log_msg(0, "carp_state_tracker: failed to renew event");
-	return;
+	if (len >= sizeof(struct if_msghdr) &&
+	    ifm->ifm_version == RTM_VERSION &&
+	    ifm->ifm_type == RTM_IFINFO)
+		carp_update_state(carp_map_state(ifm->ifm_data.ifi_link_state));
 }
 
-/* Initialize the CARP state tracker. */
+void
+carp_read_message(fd_set *fds)
+{
+	if (cfgstate.route_socket != -1)
+		if (FD_ISSET(cfgstate.route_socket, fds))
+			(void)carp_read();
+}
+
+/* Initialize the CARP state. */
 int
 carp_init(void)
 {
-	enum RUNSTATE initial_state;
+	cfgstate.route_socket = -1;
 
 	if (cfgstate.lockedstate != INIT) {
 		cfgstate.runstate = cfgstate.lockedstate;
 		log_msg(1, "carp_init: locking runstate to %s",
-		    cfgstate.runstate == MASTER ? "MASTER" : "SLAVE");
+		    carp_state_name(cfgstate.runstate));
 		return 0;
 	}
 
-	initial_state = carp_get_state(cfgstate.carp_ifname);
-	if (initial_state == FAIL) {
+	if (!cfgstate.carp_ifname || !*cfgstate.carp_ifname) {
+		fprintf(stderr, "No carp interface\n");
+		return -1;
+	}
+
+	cfgstate.carp_ifindex = if_nametoindex(cfgstate.carp_ifname);
+	if (!cfgstate.carp_ifindex) {
+		fprintf(stderr, "No carp interface index\n");
+		return -1;
+	}
+
+	cfgstate.route_socket = socket(PF_ROUTE, SOCK_RAW, 0);
+	if (cfgstate.route_socket < 0) {
+		fprintf(stderr, "No routing socket\n");
+		return -1;
+	}
+
+	cfgstate.runstate = carp_get_state(cfgstate.carp_ifname);
+	if (cfgstate.runstate == FAIL) {
 		fprintf(stderr, "Failed to check interface \"%s\".\n",
 		    cfgstate.carp_ifname);
 		fprintf(stderr, "Correct or manually select runstate.\n");
 		return -1;
 	}
+	log_msg(1, "carp_init: initializing runstate to %s",
+	    carp_state_name(cfgstate.runstate));	
 
-	return timer_add("carp_state_tracker", 0, carp_state_tracker, NULL);
+	return 0;
 }
diff --git a/usr.sbin/sasyncd/conf.y b/usr.sbin/sasyncd/conf.y
index 1156ff6b1b0..51108fd5293 100644
--- a/usr.sbin/sasyncd/conf.y
+++ b/usr.sbin/sasyncd/conf.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: conf.y,v 1.8 2006/03/31 17:38:18 pat Exp $	*/
+/*	$OpenBSD: conf.y,v 1.9 2006/06/01 22:43:12 mcbride Exp $	*/
 
 /*
  * Copyright (c) 2005 Håkan Olsson.  All rights reserved.
@@ -62,7 +62,7 @@ void	yyerror(const char *);
 %token SKIPSLAVE
 %token <string> STRING
 %token <val>	VALUE
-%type  <val>	af port interval mode flushmode
+%type  <val>	af port mode flushmode
 
 %%
 /* Rules */
@@ -97,23 +97,17 @@ modes		: SKIPSLAVE
 		}
 		;
 
-interval	: /* empty */		{ $$ = CARP_DEFAULT_INTERVAL; }
-		| INTERVAL VALUE	{ $$ = $2; }
-		;
-
 flushmode	: STARTUP		{ $$ = FM_STARTUP; }
 		| NEVER			{ $$ = FM_NEVER; }
 		| SYNC			{ $$ = FM_SYNC; }
 		;
 
-setting		: CARP INTERFACE STRING interval
+setting		: CARP INTERFACE STRING
 		{
 			if (cfgstate.carp_ifname)
 				free(cfgstate.carp_ifname);
 			cfgstate.carp_ifname = $3;
-			cfgstate.carp_check_interval = $4;
-			log_msg(2, "config: carp interface %s interval %d",
-			    $3, $4);
+			log_msg(2, "config: carp interface %s", $3);
 		}
 		| FLUSHMODE flushmode
 		{
@@ -204,7 +198,6 @@ match(char *token)
 		{ "inet", INET },
 		{ "inet6", INET6 },
 		{ "interface", INTERFACE },
-		{ "interval", INTERVAL },
 		{ "listen", LISTEN },
 		{ "master", Y_MASTER },
 		{ "mode", MODE },
@@ -346,7 +339,6 @@ conf_init(int argc, char **argv)
 	cfgstate.runstate = INIT;
 	LIST_INIT(&cfgstate.peerlist);
 
-	cfgstate.carp_check_interval = CARP_DEFAULT_INTERVAL;
 	cfgstate.listen_port = SASYNCD_DEFAULT_PORT;
 
 	while ((ch = getopt(argc, argv, "c:dv")) != -1) {
diff --git a/usr.sbin/sasyncd/net_ctl.c b/usr.sbin/sasyncd/net_ctl.c
index 820551b4cad..811ed648ba5 100644
--- a/usr.sbin/sasyncd/net_ctl.c
+++ b/usr.sbin/sasyncd/net_ctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: net_ctl.c,v 1.6 2005/05/26 19:19:51 ho Exp $	*/
+/*	$OpenBSD: net_ctl.c,v 1.7 2006/06/01 22:43:12 mcbride Exp $	*/
 
 /*
  * Copyright (c) 2005 Håkan Olsson.  All rights reserved.
@@ -53,8 +53,6 @@ struct ctlmsg {
 static int
 net_ctl_check_state(struct syncpeer *p, enum RUNSTATE nstate)
 {
-	static char	*runstate[] = CARPSTATES;
-
 	if (nstate < INIT || nstate > FAIL) {
 		log_msg(0, "net_ctl: got bad state %d from peer \"%s\"",
 		    nstate, p->name);
@@ -70,7 +68,7 @@ net_ctl_check_state(struct syncpeer *p, enum RUNSTATE nstate)
 	if (p->runstate != nstate) {
 		p->runstate = nstate;
 		log_msg(1, "net_ctl: peer \"%s\" state change to %s", p->name,
-		    runstate[nstate]);
+		    carp_state_name(nstate));
 	}
 	return 0;
 }
@@ -181,7 +179,6 @@ void
 net_ctl_update_state(void)
 {
 	struct syncpeer *p;
-	static char	*carpstate[] = CARPSTATES;
 
 	/* We may have new peers available.  */
 	net_connect();
@@ -190,7 +187,7 @@ net_ctl_update_state(void)
 		if (p->socket == -1)
 			continue;
 		log_msg(4, "net_ctl: sending my state %s to peer \"%s\"",
-		    carpstate[cfgstate.runstate], p->name);
+		    carp_state_name(cfgstate.runstate), p->name);
 		net_ctl_send_state(p);
 	}
 }
diff --git a/usr.sbin/sasyncd/sasyncd.c b/usr.sbin/sasyncd/sasyncd.c
index d5193fa4b5e..d9277382b93 100644
--- a/usr.sbin/sasyncd/sasyncd.c
+++ b/usr.sbin/sasyncd/sasyncd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sasyncd.c,v 1.9 2005/05/26 19:18:16 ho Exp $	*/
+/*	$OpenBSD: sasyncd.c,v 1.10 2006/06/01 22:43:12 mcbride Exp $	*/
 
 /*
  * Copyright (c) 2005 Håkan Olsson.  All rights reserved.
@@ -92,6 +92,10 @@ sasyncd_run(pid_t ppid)
 		if (cfgstate.pfkey_socket + 1 > maxfd)
 			maxfd = cfgstate.pfkey_socket + 1;
 
+		carp_set_rfd(rfds);
+		if (cfgstate.route_socket + 1 > maxfd)
+			maxfd = cfgstate.route_socket + 1;
+
 		timeout = &tv;
 		timer_next_event(&tv);
 
@@ -106,6 +110,7 @@ sasyncd_run(pid_t ppid)
 			net_send_messages(wfds);
 			pfkey_read_message(rfds);
 			pfkey_send_message(wfds);
+			carp_read_message(rfds);
 		}
 		timer_run();
 
diff --git a/usr.sbin/sasyncd/sasyncd.conf.5 b/usr.sbin/sasyncd/sasyncd.conf.5
index 90b12e2a13d..05981e463cc 100644
--- a/usr.sbin/sasyncd/sasyncd.conf.5
+++ b/usr.sbin/sasyncd/sasyncd.conf.5
@@ -1,4 +1,4 @@
-.\" $OpenBSD: sasyncd.conf.5,v 1.10 2006/05/26 04:02:59 deraadt Exp $
+.\" $OpenBSD: sasyncd.conf.5,v 1.11 2006/06/01 22:43:12 mcbride Exp $
 .\"
 .\" Copyright (c) 2005 Håkan Olsson.  All rights reserved.
 .\"
@@ -60,16 +60,13 @@ The following configuration settings are understood:
 .Bl -tag -width Ds
 .It Xo
 .Ic carp interface
-.Ar interface Op Ic interval Ar seconds
+.Ar interface
 .Xc
 Specify which
 .Xr carp 4
 interface
 .Nm sasyncd
 should track master/slave state on.
-Optionally state how often the daemon should check the interface
-for state changes.
-Defaults to once every 10 seconds.
 .It Ic flushmode sync | startup | never
 Controls how the
 .Xr sasyncd 8
diff --git a/usr.sbin/sasyncd/sasyncd.h b/usr.sbin/sasyncd/sasyncd.h
index c5d5ba6a798..f5ecd723831 100644
--- a/usr.sbin/sasyncd/sasyncd.h
+++ b/usr.sbin/sasyncd/sasyncd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sasyncd.h,v 1.8 2005/05/28 01:07:52 ho Exp $	*/
+/*	$OpenBSD: sasyncd.h,v 1.9 2006/06/01 22:43:12 mcbride Exp $	*/
 
 /*
  * Copyright (c) 2005 Håkan Olsson.  All rights reserved.
@@ -46,12 +46,14 @@ struct cfgstate {
 	u_int32_t	 flags;
 
 	char		*carp_ifname;
-	int		 carp_check_interval;
+	int		 carp_ifindex;
 
 	char		*sharedkey;
 
 	int		 pfkey_socket;
 
+	int		 route_socket;
+
 	char		*listen_on;
 	in_port_t	 listen_port;
 	sa_family_t	 listen_family;
@@ -94,8 +96,12 @@ extern struct cfgstate	cfgstate;
 int	conf_init(int, char **);
 
 /* carp.c */
-void	carp_check_state(void);
-int	carp_init(void);
+int		carp_init(void);
+void		carp_check_state(void);
+void		carp_update_state(enum RUNSTATE);
+void		carp_set_rfd(fd_set *);
+void		carp_read_message(fd_set *);
+const char*	carp_state_name(enum RUNSTATE);
 
 /* log.c */
 /*