From: krw <krw@openbsd.org>
Date: Sun, 11 May 2014 12:40:37 +0000 (+0000)
Subject: Rework/restore recorded lease handling. Actually use 'lease'
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=a0eff9f4525e06432caec60b839413096e805b51;p=openbsd

Rework/restore recorded lease handling. Actually use 'lease'
statements in dhclient.conf.

Recorded and static leases should now be bound to interfaces when
appropriate.

.... Ken
---

diff --git a/sbin/dhclient/clparse.c b/sbin/dhclient/clparse.c
index 69b30bc801a..ebbda2c0c25 100644
--- a/sbin/dhclient/clparse.c
+++ b/sbin/dhclient/clparse.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clparse.c,v 1.85 2014/05/05 18:02:49 krw Exp $	*/
+/*	$OpenBSD: clparse.c,v 1.86 2014/05/11 12:40:37 krw Exp $	*/
 
 /* Parser for dhclient config and lease files. */
 
@@ -486,55 +486,21 @@ parse_client_lease_statement(FILE *cfile, int is_static)
 	}
 
 	/*
-	 * The new lease may supersede a lease that's not the active
-	 * lease but is still on the lease list, so scan the lease list
-	 * looking for a lease with the same address, and if we find it,
-	 * toss it.
+	 * The new lease will supersede a lease of the same type and for
+	 * the same address.
 	 */
 	TAILQ_FOREACH_SAFE(lp, &client->leases, next, pl) {
-		if (lp->address.s_addr == lease->address.s_addr) {
+		if (lp->address.s_addr == lease->address.s_addr &&
+		    lp->is_static == lease->is_static) {
 			TAILQ_REMOVE(&client->leases, lp, next);
 			free_client_lease(lp);
 		}
 	}
 
-	/*
-	 * If this is a preloaded lease, just put it on the list of
-	 * recorded leases - don't make it the active lease.
-	 */
-	if (is_static) {
-		TAILQ_INSERT_HEAD(&client->leases, lease, next);
-		return;
-	}
-
-	/*
-	 * The last lease in the lease file on a particular interface is
-	 * the active lease for that interface.    Of course, we don't
-	 * know what the last lease in the file is until we've parsed
-	 * the whole file, so at this point, we assume that the lease we
-	 * just parsed is the active lease for its interface.   If
-	 * there's already an active lease for the interface, and this
-	 * lease is for the same ip address, then we just toss the old
-	 * active lease and replace it with this one.   If this lease is
-	 * for a different address, then if the old active lease has
-	 * expired, we dump it; if not, we put it on the list of leases
-	 * for this interface which are still valid but no longer
-	 * active.
-	 */
-	if (client->active) {
-		if (client->active->expiry < time(NULL))
-			free_client_lease(client->active);
-		else if (client->active->address.s_addr ==
-		    lease->address.s_addr)
-			free_client_lease(client->active);
-		else {
-			TAILQ_INSERT_HEAD(&client->leases, client->active,
-			    next);
-		}
-	}
-	client->active = lease;
-
-	/* Phew. */
+	if (is_static)
+		TAILQ_INSERT_TAIL(&client->leases, lease, next);
+	else
+		TAILQ_INSERT_HEAD(&client->leases, lease,  next);
 }
 
 /*
diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c
index 993a6914201..8398522eb13 100644
--- a/sbin/dhclient/dhclient.c
+++ b/sbin/dhclient/dhclient.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhclient.c,v 1.303 2014/05/05 18:02:49 krw Exp $	*/
+/*	$OpenBSD: dhclient.c,v 1.304 2014/05/11 12:40:37 krw Exp $	*/
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -626,10 +626,31 @@ usage(void)
 void
 state_reboot(void)
 {
+	struct client_lease *lp, *pl;
+	time_t cur_time;
+
 	cancel_timeout();
 	deleting.s_addr = INADDR_ANY;
 	adding.s_addr = INADDR_ANY;
 
+	time(&cur_time);
+	if (client->active && client->active->expiry <= cur_time) {
+		free_client_lease(client->active);
+		client->active = NULL;
+	}
+
+	/* Run through the list of leases and see if one can be used. */
+	TAILQ_FOREACH_SAFE(lp, &client->leases, next, pl) {
+		if (client->active || lp->is_static)
+			break;
+		else if (lp->expiry <= cur_time)
+			free_client_lease(lp);
+		else {
+			client->active = lp;
+			break;
+		}
+	}
+
 	/* If we don't remember an active lease, go straight to INIT. */
 	if (!client->active || client->active->is_bootp) {
 		client->state = S_INIT;
@@ -784,7 +805,16 @@ bind_lease(void)
 {
 	struct in_addr gateway, mask;
 	struct option_data *options, *opt;
-	struct client_lease *lease;
+	struct client_lease *lease, *pl;
+
+	/*
+	 * If it's been here before (e.g. static lease), clear out any
+	 * old resolv_conf.
+	 */
+	if (client->new->resolv_conf) {
+		free(client->new->resolv_conf);
+		client->new->resolv_conf = NULL;
+	}
 
 	lease = apply_defaults(client->new);
 	options = lease->options;
@@ -866,20 +896,28 @@ bind_lease(void)
 		    S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH, 0, 0,
 		    client->new->resolv_conf, strlen(client->new->resolv_conf));
 
-	/* Replace the old active lease with the new one. */
 newlease:
-	if (client->active)
-		free_client_lease(client->active);
+	/* Replace the old active lease with the new one. */
 	client->active = client->new;
 	client->new = NULL;
+	rewrite_option_db(client->active, lease);
+	free_client_lease(lease);
+
+	/* Remove previous dynamic lease(es) for this address. */
+	TAILQ_FOREACH_SAFE(lease, &client->leases, next, pl) {
+		if (lease->is_static)
+			break;
+		if (client->active != lease && lease->address.s_addr ==
+		    client->active->address.s_addr)
+			free_client_lease(lease);
+	}
+	if (!client->active->is_static)
+		TAILQ_INSERT_HEAD(&client->leases, client->active,  next);
 
 	client->state = S_BOUND;
 
 	/* Write out new leases file. */
 	rewrite_client_leases();
-	rewrite_option_db(client->active, lease);
-
-	free_client_lease(lease);
 
 	/* Set timeout to start the renewal process. */
 	set_timeout(client->active->renewal, state_bound);
@@ -1185,73 +1223,30 @@ send_discover(void)
 void
 state_panic(void)
 {
-	struct client_lease *loop = client->active;
+	struct client_lease *lp, *pl;
 	time_t cur_time;
 
 	time(&cur_time);
 	note("No acceptable DHCPOFFERS received.");
 
-	/*
-	 * We may not have an active lease, but we may have some predefined
-	 * leases that we can try.
-	 */
-	if (!client->active && !TAILQ_EMPTY(&client->leases))
-		goto activate_next;
-
 	/* Run through the list of leases and see if one can be used. */
-	while (client->active) {
-		if (client->active->expiry > cur_time) {
+	time(&cur_time);
+	TAILQ_FOREACH_SAFE(lp, &client->leases, next, pl) {
+		if (lp->is_static) {
+			set_lease_times(lp);
+			note("Trying static lease %s", inet_ntoa(lp->address));
+		} else if (lp->expiry <= cur_time) {
+			free_client_lease(lp);
+			continue;
+		} else
 			note("Trying recorded lease %s",
-			    inet_ntoa(client->active->address));
-
-			/*
-			 * If the old lease is still good and doesn't
-			 * yet need renewal, go into BOUND state and
-			 * timeout at the renewal time.
-			 */
-			if (cur_time < client->active->renewal) {
-				client->state = S_BOUND;
-				note("bound: renewal in %lld seconds.",
-				    (long long)(client->active->renewal
-				    - cur_time));
-				set_timeout(client->active->renewal,
-				    state_bound);
-			} else {
-				client->state = S_BOUND;
-				note("bound: immediate renewal.");
-				state_bound();
-			}
-			go_daemon();
-			return;
-		}
+			    inet_ntoa(lp->address));
 
-		/* If there are no other leases, give up. */
-		if (TAILQ_EMPTY(&client->leases)) {
-			TAILQ_INSERT_HEAD(&client->leases, client->active,
-			    next);
-			client->active = NULL;
-			break;
-		}
-
-activate_next:
-		/*
-		 * Otherwise, put the active lease at the end of the lease
-		 * list, and try another lease.
-		 */
-		if (client->active)
-			TAILQ_INSERT_TAIL(&client->leases, client->active,
-			    next);
-		client->active = TAILQ_FIRST(&client->leases);
-		TAILQ_REMOVE(&client->leases, client->active, next);
+		client->new = lp;
+		client->state = S_REQUESTING;
+		bind_lease();
 
-		/*
-		 * If we already tried this lease, we've exhausted the set of
-		 * leases, so we might as well give up for now.
-		 */
-		if (client->active == loop)
-			break;
-		else if (!loop)
-			loop = client->active;
+		return;
 	}
 
 	/*
@@ -1584,8 +1579,18 @@ make_decline(struct client_lease *lease)
 void
 free_client_lease(struct client_lease *lease)
 {
+	struct client_lease *lp, *pl;
 	int i;
 
+	/* Static leases are forever. */
+	if (lease->is_static)
+		return;
+
+	TAILQ_FOREACH_SAFE(lp, &client->leases, next, pl) {
+		if (lease == lp)
+			TAILQ_REMOVE(&client->leases, lp, next);
+	}
+
 	if (lease->server_name)
 		free(lease->server_name);
 	if (lease->filename)
@@ -1604,6 +1609,7 @@ rewrite_client_leases(void)
 {
 	struct client_lease *lp;
 	char *leasestr;
+	time_t cur_time;
 
 	if (!leaseFile)	/* XXX */
 		error("lease file not open");
@@ -1619,14 +1625,13 @@ rewrite_client_leases(void)
 	 * the leases in client->leases in reverse order to recreate
 	 * the chonological order required.
 	 */
+	time(&cur_time);
 	TAILQ_FOREACH_REVERSE(lp, &client->leases, _leases, next) {
-		/* Skip any leases that duplicate the active lease address. */
-		if (client->active && lp->address.s_addr ==
-		    client->active->address.s_addr)
-			continue;
 		/* Don't write out static leases from dhclient.conf. */
 		if (lp->is_static)
 			continue;
+		if (lp->expiry <= cur_time)
+			continue;
 		leasestr = lease_as_string("lease", lp);
 		if (leasestr)
 			fprintf(leaseFile, "%s", leasestr);
@@ -1634,14 +1639,6 @@ rewrite_client_leases(void)
 			warning("cannot make lease into string");
 	}
 
-	if (client->active) {
-		leasestr = lease_as_string("lease", client->active);
-		if (leasestr)
-			fprintf(leaseFile, "%s", leasestr);
-		else
-			warning("cannot make lease into string");
-	}
-
 	fflush(leaseFile);
 	ftruncate(fileno(leaseFile), ftello(leaseFile));
 	fsync(fileno(leaseFile));