We accept either the first offer received, or an offer for the

current address if one arrives inside select_timeout. So there
is no need to keep a list of received offers. Just keep the
best one and DECLINE the rest. Nuke now unused 'offered_leases'
TAILQ.

Also fixes the oddity that the *last* offer for the current
address is taken rather than the *first*.

diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c
index a1bb46c..e1b09c4 100644 (file)
--- a/sbin/dhclient/dhclient.c
+++ b/sbin/dhclient/dhclient.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: dhclient.c,v 1.429 2017/06/17 15:53:03 krw Exp $      */
+/*     $OpenBSD: dhclient.c,v 1.430 2017/06/17 16:58:55 krw Exp $      */
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -564,7 +564,6 @@ main(int argc, char *argv[])
        TAILQ_INIT(&config->reject_list);
 
        TAILQ_INIT(&ifi->leases);
-       TAILQ_INIT(&ifi->offered_leases);
 
        read_client_conf(ifi);
 
@@ -809,33 +808,17 @@ state_init(struct interface_info *ifi)
 void
 state_selecting(struct interface_info *ifi)
 {
-       struct client_lease *lease, *picked;
+       struct option_data *option;
 
        cancel_timeout();
 
-       if (TAILQ_EMPTY(&ifi->offered_leases)) {
+       if (ifi->new == NULL) {
                state_panic(ifi);
                return;
        }
 
-       picked = TAILQ_FIRST(&ifi->offered_leases);
-       TAILQ_REMOVE(&ifi->offered_leases, picked, next);
-
-       /* DECLINE the rest of the offers. */
-       while (!TAILQ_EMPTY(&ifi->offered_leases)) {
-               lease = TAILQ_FIRST(&ifi->offered_leases);
-               TAILQ_REMOVE(&ifi->offered_leases, lease, next);
-               make_decline(ifi, lease);
-               send_decline(ifi);
-               free_client_lease(lease);
-       }
-
        /* If it was a BOOTREPLY, we can just take the lease right now. */
-       if (BOOTP_LEASE(picked)) {
-               struct option_data *option;
-
-               ifi->new = picked;
-
+       if (BOOTP_LEASE(ifi->new)) {
                /*
                 * Set (unsigned 32 bit) options
                 *
@@ -882,10 +865,10 @@ state_selecting(struct interface_info *ifi)
         * the current xid, as all offers should have had the same
         * one.
         */
-       make_request(ifi, picked);
+       make_request(ifi, ifi->new);
 
        /* Toss the lease we picked - we'll get it back in a DHCPACK. */
-       free_client_lease(picked);
+       free_client_lease(ifi->new);
 
        send_request(ifi);
 }
@@ -1104,8 +1087,7 @@ state_bound(struct interface_info *ifi)
 void
 dhcpoffer(struct interface_info *ifi, struct option_data *options, char *info)
 {
-       struct dhcp_packet *packet = &ifi->recv_packet;
-       struct client_lease *lease, *lp;
+       struct client_lease *lease;
        time_t stop_selecting;
 
        if (ifi->state != S_SELECTING) {
@@ -1117,28 +1099,19 @@ dhcpoffer(struct interface_info *ifi, struct option_data *options, char *info)
 
        log_info("%s", info);
 
-       /* If we've already seen this lease, don't record it again. */
-       TAILQ_FOREACH(lp, &ifi->offered_leases, next) {
-               if (!memcmp(&lp->address.s_addr, &packet->yiaddr,
-                   sizeof(in_addr_t))) {
-#ifdef DEBUG
-                       log_debug("Duplicate %s.", info);
-#endif /* DEBUG */
-                       return;
-               }
-       }
-
        lease = packet_to_lease(ifi, options);
        if (lease != NULL) {
-               if (TAILQ_EMPTY(&ifi->offered_leases)) {
-                       TAILQ_INSERT_HEAD(&ifi->offered_leases, lease, next);
+               if (ifi->new == NULL) {
+                       ifi->new = lease;
                } else if (lease->address.s_addr ==
                    ifi->requested_address.s_addr) {
-                       /* The expected lease - put it first. */
-                       TAILQ_INSERT_HEAD(&ifi->offered_leases, lease, next);
-               } else {
-                       /* Put it at the end of the list. */
-                       TAILQ_INSERT_TAIL(&ifi->offered_leases, lease, next);
+                       free_client_lease(ifi->new);
+                       ifi->new = lease;
+               }
+               if (ifi->new != lease) {
+                       make_decline(ifi, lease);
+                       send_decline(ifi);
+                       free_client_lease(lease);
                }
        }
 

diff --git a/sbin/dhclient/dhcpd.h b/sbin/dhclient/dhcpd.h
index 8f64d35..dc46e33 100644 (file)
--- a/sbin/dhclient/dhcpd.h
+++ b/sbin/dhclient/dhcpd.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: dhcpd.h,v 1.184 2017/06/17 15:53:03 krw Exp $ */
+/*     $OpenBSD: dhcpd.h,v 1.185 2017/06/17 16:58:55 krw Exp $ */
 
 /*
  * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
@@ -154,7 +154,6 @@ struct interface_info {
        struct in_addr           requested_address;
        struct client_lease     *active;
        struct client_lease     *new;
-       TAILQ_HEAD(, client_lease) offered_leases;
        TAILQ_HEAD(_leases, client_lease) leases;
 };