X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=networking%2Fzcip.c;h=45d1f7c1c25cf148825052075a0d20ea15eb9751;hb=a4d564ad7c24df2da1d8e03a7dd016f0a3d5edbd;hp=0b5bebec4d052c1d76d3a0730070c8d91951c52f;hpb=3e64e98570b2748973a66876a8b010c5d63e23be;p=oweals%2Fbusybox.git

diff --git a/networking/zcip.c b/networking/zcip.c
index 0b5bebec4..45d1f7c1c 100644
--- a/networking/zcip.c
+++ b/networking/zcip.c
@@ -6,7 +6,7 @@
  * Copyright (C) 2003 by Arthur van Hoff (avh@strangeberry.com)
  * Copyright (C) 2004 by David Brownell
  *
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
 /*
@@ -23,25 +23,33 @@
 // - avoid silent script failures, especially under load...
 // - link status monitoring (restart on link-up; stop on link-down)
 
-#include <syslog.h>
-#include <poll.h>
-#include <sys/wait.h>
+//usage:#define zcip_trivial_usage
+//usage:       "[OPTIONS] IFACE SCRIPT"
+//usage:#define zcip_full_usage "\n\n"
+//usage:       "Manage a ZeroConf IPv4 link-local address\n"
+//usage:     "\n	-f		Run in foreground"
+//usage:     "\n	-q		Quit after obtaining address"
+//usage:     "\n	-r 169.254.x.x	Request this address first"
+//usage:     "\n	-v		Verbose"
+//usage:     "\n"
+//usage:     "\nWith no -q, runs continuously monitoring for ARP conflicts,"
+//usage:     "\nexits only on I/O errors (link down etc)"
+
+#include "libbb.h"
 #include <netinet/ether.h>
-#include <net/ethernet.h>
 #include <net/if.h>
 #include <net/if_arp.h>
-#include <linux/if_packet.h>
 #include <linux/sockios.h>
 
-#include "libbb.h"
+#include <syslog.h>
 
 /* We don't need more than 32 bits of the counter */
 #define MONOTONIC_US() ((unsigned)monotonic_us())
 
 struct arp_packet {
-	struct ether_header hdr;
+	struct ether_header eth;
 	struct ether_arp arp;
-} ATTRIBUTE_PACKED;
+} PACKED;
 
 enum {
 /* 169.254.0.0 */
@@ -69,37 +77,56 @@ enum {
 	DEFEND
 };
 
-#define VDBG(fmt,args...) \
-	do { } while (0)
+#define VDBG(...) do { } while (0)
+
+
+enum {
+	sock_fd = 3
+};
+
+struct globals {
+	struct sockaddr saddr;
+	struct ether_addr eth_addr;
+} FIX_ALIASING;
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define saddr    (G.saddr   )
+#define eth_addr (G.eth_addr)
+#define INIT_G() do { } while (0)
+
 
 /**
  * Pick a random link local IP address on 169.254/16, except that
  * the first and last 256 addresses are reserved.
  */
-static void pick(struct in_addr *ip)
+static uint32_t pick(void)
 {
 	unsigned tmp;
 
 	do {
 		tmp = rand() & IN_CLASSB_HOST;
 	} while (tmp > (IN_CLASSB_HOST - 0x0200));
-	ip->s_addr = htonl((LINKLOCAL_ADDR + 0x0100) + tmp);
+	return htonl((LINKLOCAL_ADDR + 0x0100) + tmp);
 }
 
 /**
  * Broadcast an ARP packet.
  */
-static void arp(int fd, struct sockaddr *saddr, int op,
-	const struct ether_addr *source_addr, struct in_addr source_ip,
-	const struct ether_addr *target_addr, struct in_addr target_ip)
+static void arp(
+	/* int op, - always ARPOP_REQUEST */
+	/* const struct ether_addr *source_eth, - always &eth_addr */
+					struct in_addr source_ip,
+	const struct ether_addr *target_eth, struct in_addr target_ip)
 {
+	enum { op = ARPOP_REQUEST };
+#define source_eth (&eth_addr)
+
 	struct arp_packet p;
 	memset(&p, 0, sizeof(p));
 
 	// ether header
-	p.hdr.ether_type = htons(ETHERTYPE_ARP);
-	memcpy(p.hdr.ether_shost, source_addr, ETH_ALEN);
-	memset(p.hdr.ether_dhost, 0xff, ETH_ALEN);
+	p.eth.ether_type = htons(ETHERTYPE_ARP);
+	memcpy(p.eth.ether_shost, source_eth, ETH_ALEN);
+	memset(p.eth.ether_dhost, 0xff, ETH_ALEN);
 
 	// arp request
 	p.arp.arp_hrd = htons(ARPHRD_ETHER);
@@ -107,48 +134,57 @@ static void arp(int fd, struct sockaddr *saddr, int op,
 	p.arp.arp_hln = ETH_ALEN;
 	p.arp.arp_pln = 4;
 	p.arp.arp_op = htons(op);
-	memcpy(&p.arp.arp_sha, source_addr, ETH_ALEN);
+	memcpy(&p.arp.arp_sha, source_eth, ETH_ALEN);
 	memcpy(&p.arp.arp_spa, &source_ip, sizeof(p.arp.arp_spa));
-	memcpy(&p.arp.arp_tha, target_addr, ETH_ALEN);
+	memcpy(&p.arp.arp_tha, target_eth, ETH_ALEN);
 	memcpy(&p.arp.arp_tpa, &target_ip, sizeof(p.arp.arp_tpa));
 
 	// send it
-	xsendto(fd, &p, sizeof(p), saddr, sizeof(*saddr));
-
-	// Currently all callers ignore errors, that's why returns are
-	// commented out...
-	//return 0;
+	// Even though sock_fd is already bound to saddr, just send()
+	// won't work, because "socket is not connected"
+	// (and connect() won't fix that, "operation not supported").
+	// Thus we sendto() to saddr. I wonder which sockaddr
+	// (from bind() or from sendto()?) kernel actually uses
+	// to determine iface to emit the packet from...
+	xsendto(sock_fd, &p, sizeof(p), &saddr, sizeof(saddr));
+#undef source_eth
 }
 
 /**
- * Run a script. argv[2] is already NULL.
+ * Run a script.
+ * argv[0]:intf argv[1]:script_name argv[2]:junk argv[3]:NULL
  */
-static int run(char *argv[3], const char *intf, struct in_addr *ip)
+static int run(char *argv[3], const char *param, struct in_addr *ip)
 {
 	int status;
+	char *addr = addr; /* for gcc */
+	const char *fmt = "%s %s %s" + 3;
+
+	argv[2] = (char*)param;
 
-	VDBG("%s run %s %s\n", intf, argv[0], argv[1]);
+	VDBG("%s run %s %s\n", argv[0], argv[1], argv[2]);
 
 	if (ip) {
-		char *addr = inet_ntoa(*ip);
-		setenv("ip", addr, 1);
-		bb_info_msg("%s %s %s", argv[1], intf, addr);
+		addr = inet_ntoa(*ip);
+		xsetenv("ip", addr);
+		fmt -= 3;
 	}
+	bb_info_msg(fmt, argv[2], argv[0], addr);
 
-	status = wait4pid(spawn(argv));
+	status = spawn_and_wait(argv + 1);
 	if (status < 0) {
-		bb_perror_msg("%s %s", argv[1], intf);
+		bb_perror_msg("%s %s %s" + 3, argv[2], argv[0]);
 		return -errno;
 	}
 	if (status != 0)
-		bb_error_msg("script %s %s failed, exitcode=%d", argv[0], argv[1], status);
+		bb_error_msg("script %s %s failed, exitcode=%d", argv[1], argv[2], status & 0xff);
 	return status;
 }
 
 /**
  * Return milliseconds of random delay, up to "secs" seconds.
  */
-static unsigned ALWAYS_INLINE ms_rdelay(unsigned secs)
+static ALWAYS_INLINE unsigned random_delay_ms(unsigned secs)
 {
 	return rand() % (secs * 1000);
 }
@@ -156,25 +192,19 @@ static unsigned ALWAYS_INLINE ms_rdelay(unsigned secs)
 /**
  * main program
  */
-int zcip_main(int argc, char **argv);
-int zcip_main(int argc, char **argv)
+int zcip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int zcip_main(int argc UNUSED_PARAM, char **argv)
 {
-	int state = PROBE;
-	struct ether_addr eth_addr;
-	const char *why;
-	int fd;
+	int state;
 	char *r_opt;
 	unsigned opts;
 
-	/* Ugly trick, but I want these zeroed in one go */
+	// ugly trick, but I want these zeroed in one go
 	struct {
 		const struct in_addr null_ip;
 		const struct ether_addr null_addr;
-		struct sockaddr saddr;
 		struct in_addr ip;
 		struct ifreq ifr;
-		char *intf;
-		char *script_av[3];
 		int timeout_ms; /* must be signed */
 		unsigned conflicts;
 		unsigned nprobes;
@@ -184,11 +214,8 @@ int zcip_main(int argc, char **argv)
 	} L;
 #define null_ip    (L.null_ip   )
 #define null_addr  (L.null_addr )
-#define saddr      (L.saddr     )
 #define ip         (L.ip        )
 #define ifr        (L.ifr       )
-#define intf       (L.intf      )
-#define script_av  (L.script_av )
 #define timeout_ms (L.timeout_ms)
 #define conflicts  (L.conflicts )
 #define nprobes    (L.nprobes   )
@@ -197,15 +224,25 @@ int zcip_main(int argc, char **argv)
 #define verbose    (L.verbose   )
 
 	memset(&L, 0, sizeof(L));
+	INIT_G();
 
 #define FOREGROUND (opts & 1)
 #define QUIT       (opts & 2)
 	// parse commandline: prog [options] ifname script
 	// exactly 2 args; -v accumulates and implies -f
 	opt_complementary = "=2:vv:vf";
-	opts = getopt32(argc, argv, "fqr:v", &r_opt, &verbose);
+	opts = getopt32(argv, "fqr:v", &r_opt, &verbose);
+#if !BB_MMU
+	// on NOMMU reexec early (or else we will rerun things twice)
+	if (!FOREGROUND)
+		bb_daemonize_or_rexec(0 /*was: DAEMON_CHDIR_ROOT*/, argv);
+#endif
+	// open an ARP socket
+	// (need to do it before openlog to prevent openlog from taking
+	// fd 3 (sock_fd==3))
+	xmove_fd(xsocket(AF_PACKET, SOCK_PACKET, htons(ETH_P_ARP)), sock_fd);
 	if (!FOREGROUND) {
-		/* Do it early, before all bb_xx_msg calls */
+		// do it before all bb_xx_msg calls
 		openlog(applet_name, 0, LOG_DAEMON);
 		logmode |= LOGMODE_SYSLOG;
 	}
@@ -216,45 +253,49 @@ int zcip_main(int argc, char **argv)
 			bb_error_msg_and_die("invalid link address");
 		}
 	}
-	// On NOMMU reexec early (or else we will rerun things twice)
-#if !BB_MMU
-	if (!FOREGROUND)
-		bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
-#endif
-	argc -= optind;
-	argv += optind;
+	argv += optind - 1;
+
+	/* Now: argv[0]:junk argv[1]:intf argv[2]:script argv[3]:NULL */
+	/* We need to make space for script argument: */
+	argv[0] = argv[1];
+	argv[1] = argv[2];
+	/* Now: argv[0]:intf argv[1]:script argv[2]:junk argv[3]:NULL */
+#define argv_intf (argv[0])
 
-	intf = argv[0];
-	script_av[0] = argv[1];
-	setenv("interface", intf, 1);
+	xsetenv("interface", argv_intf);
 
 	// initialize the interface (modprobe, ifup, etc)
-	script_av[1] = (char*)"init";
-	if (run(script_av, intf, NULL))
+	if (run(argv, "init", NULL))
 		return EXIT_FAILURE;
 
 	// initialize saddr
+	// saddr is: { u16 sa_family; u8 sa_data[14]; }
 	//memset(&saddr, 0, sizeof(saddr));
-	safe_strncpy(saddr.sa_data, intf, sizeof(saddr.sa_data));
+	//TODO: are we leaving sa_family == 0 (AF_UNSPEC)?!
+	safe_strncpy(saddr.sa_data, argv_intf, sizeof(saddr.sa_data));
 
-	// open an ARP socket
-	fd = xsocket(PF_PACKET, SOCK_PACKET, htons(ETH_P_ARP));
 	// bind to the interface's ARP socket
-	xbind(fd, &saddr, sizeof(saddr));
+	xbind(sock_fd, &saddr, sizeof(saddr));
 
 	// get the interface's ethernet address
 	//memset(&ifr, 0, sizeof(ifr));
-	strncpy(ifr.ifr_name, intf, sizeof(ifr.ifr_name));
-	xioctl(fd, SIOCGIFHWADDR, &ifr);
+	strncpy_IFNAMSIZ(ifr.ifr_name, argv_intf);
+	xioctl(sock_fd, SIOCGIFHWADDR, &ifr);
 	memcpy(&eth_addr, &ifr.ifr_hwaddr.sa_data, ETH_ALEN);
 
 	// start with some stable ip address, either a function of
 	// the hardware address or else the last address we used.
+	// we are taking low-order four bytes, as top-order ones
+	// aren't random enough.
 	// NOTE: the sequence of addresses we try changes only
 	// depending on when we detect conflicts.
-	srand(*(unsigned*)&ifr.ifr_hwaddr.sa_data);
+	{
+		uint32_t t;
+		move_from_unaligned32(t, ((char *)&eth_addr + 2));
+		srand(t);
+	}
 	if (ip.s_addr == 0)
-		pick(&ip);
+		ip.s_addr = pick();
 
 	// FIXME cases to handle:
 	//  - zcip already running!
@@ -263,35 +304,42 @@ int zcip_main(int argc, char **argv)
 	// daemonize now; don't delay system startup
 	if (!FOREGROUND) {
 #if BB_MMU
-		bb_daemonize(DAEMON_CHDIR_ROOT);
+		bb_daemonize(0 /*was: DAEMON_CHDIR_ROOT*/);
 #endif
-		bb_info_msg("start, interface %s", intf);
+		bb_info_msg("start, interface %s", argv_intf);
 	}
 
 	// run the dynamic address negotiation protocol,
 	// restarting after address conflicts:
 	//  - start with some address we want to try
 	//  - short random delay
-	//  - arp probes to see if another host else uses it
+	//  - arp probes to see if another host uses it
 	//  - arp announcements that we're claiming it
 	//  - use it
 	//  - defend it, within limits
+	// exit if:
+	// - address is successfully obtained and -q was given:
+	//   run "<script> config", then exit with exitcode 0
+	// - poll error (when does this happen?)
+	// - read error (when does this happen?)
+	// - sendto error (in arp()) (when does this happen?)
+	// - revents & POLLERR (link down). run "<script> deconfig" first
+	state = PROBE;
 	while (1) {
 		struct pollfd fds[1];
 		unsigned deadline_us;
 		struct arp_packet p;
+		int source_ip_conflict;
+		int target_ip_conflict;
 
-		int source_ip_conflict = 0;
-		int target_ip_conflict = 0;
-
-		fds[0].fd = fd;
+		fds[0].fd = sock_fd;
 		fds[0].events = POLLIN;
 		fds[0].revents = 0;
 
 		// poll, being ready to adjust current timeout
 		if (!timeout_ms) {
-			timeout_ms = ms_rdelay(PROBE_WAIT);
-			// FIXME setsockopt(fd, SO_ATTACH_FILTER, ...) to
+			timeout_ms = random_delay_ms(PROBE_WAIT);
+			// FIXME setsockopt(sock_fd, SO_ATTACH_FILTER, ...) to
 			// make the kernel filter out all packets except
 			// ones we'd care about.
 		}
@@ -299,8 +347,13 @@ int zcip_main(int argc, char **argv)
 		deadline_us = MONOTONIC_US() + timeout_ms * 1000;
 
 		VDBG("...wait %d %s nprobes=%u, nclaims=%u\n",
-				timeout_ms, intf, nprobes, nclaims);
-		switch (poll(fds, 1, timeout_ms)) {
+				timeout_ms, argv_intf, nprobes, nclaims);
+
+		switch (safe_poll(fds, 1, timeout_ms)) {
+
+		default:
+			//bb_perror_msg("poll"); - done in safe_poll
+			return EXIT_FAILURE;
 
 		// timeout
 		case 0:
@@ -312,23 +365,23 @@ int zcip_main(int argc, char **argv)
 				if (nprobes < PROBE_NUM) {
 					nprobes++;
 					VDBG("probe/%u %s@%s\n",
-							nprobes, intf, inet_ntoa(ip));
-					arp(fd, &saddr, ARPOP_REQUEST,
-							&eth_addr, null_ip,
-							&null_addr, ip);
+							nprobes, argv_intf, inet_ntoa(ip));
 					timeout_ms = PROBE_MIN * 1000;
-					timeout_ms += ms_rdelay(PROBE_MAX - PROBE_MIN);
+					timeout_ms += random_delay_ms(PROBE_MAX - PROBE_MIN);
+					arp(/* ARPOP_REQUEST, */
+							/* &eth_addr, */ null_ip,
+							&null_addr, ip);
 				}
 				else {
 					// Switch to announce state.
 					state = ANNOUNCE;
 					nclaims = 0;
 					VDBG("announce/%u %s@%s\n",
-							nclaims, intf, inet_ntoa(ip));
-					arp(fd, &saddr, ARPOP_REQUEST,
-							&eth_addr, ip,
-							&eth_addr, ip);
+							nclaims, argv_intf, inet_ntoa(ip));
 					timeout_ms = ANNOUNCE_INTERVAL * 1000;
+					arp(/* ARPOP_REQUEST, */
+							/* &eth_addr, */ ip,
+							&eth_addr, ip);
 				}
 				break;
 			case RATE_LIMIT_PROBE:
@@ -337,11 +390,11 @@ int zcip_main(int argc, char **argv)
 				state = ANNOUNCE;
 				nclaims = 0;
 				VDBG("announce/%u %s@%s\n",
-						nclaims, intf, inet_ntoa(ip));
-				arp(fd, &saddr, ARPOP_REQUEST,
-						&eth_addr, ip,
-						&eth_addr, ip);
+						nclaims, argv_intf, inet_ntoa(ip));
 				timeout_ms = ANNOUNCE_INTERVAL * 1000;
+				arp(/* ARPOP_REQUEST, */
+						/* &eth_addr, */ ip,
+						&eth_addr, ip);
 				break;
 			case ANNOUNCE:
 				// timeouts in the ANNOUNCE state mean no conflicting ARP packets
@@ -349,19 +402,18 @@ int zcip_main(int argc, char **argv)
 				if (nclaims < ANNOUNCE_NUM) {
 					nclaims++;
 					VDBG("announce/%u %s@%s\n",
-							nclaims, intf, inet_ntoa(ip));
-					arp(fd, &saddr, ARPOP_REQUEST,
-							&eth_addr, ip,
-							&eth_addr, ip);
+							nclaims, argv_intf, inet_ntoa(ip));
 					timeout_ms = ANNOUNCE_INTERVAL * 1000;
+					arp(/* ARPOP_REQUEST, */
+							/* &eth_addr, */ ip,
+							&eth_addr, ip);
 				}
 				else {
 					// Switch to monitor state.
 					state = MONITOR;
 					// link is ok to use earlier
 					// FIXME update filters
-					script_av[1] = (char*)"config";
-					run(script_av, intf, &ip);
+					run(argv, "config", &ip);
 					ready = 1;
 					conflicts = 0;
 					timeout_ms = -1; // Never timeout in the monitor state.
@@ -381,14 +433,15 @@ int zcip_main(int argc, char **argv)
 			default:
 				// Invalid, should never happen.  Restart the whole protocol.
 				state = PROBE;
-				pick(&ip);
+				ip.s_addr = pick();
 				timeout_ms = 0;
 				nprobes = 0;
 				nclaims = 0;
 				break;
 			} // switch (state)
 			break; // case 0 (timeout)
-		// packets arriving
+
+		// packets arriving, or link went down
 		case 1:
 			// We need to adjust the timeout in case we didn't receive
 			// a conflicting packet.
@@ -401,8 +454,7 @@ int zcip_main(int argc, char **argv)
 					timeout_ms = 0;
 				} else {
 					VDBG("adjusting timeout\n");
-					timeout_ms = diff / 1000;
-					if (!timeout_ms) timeout_ms = 1;
+					timeout_ms = (diff / 1000) | 1; /* never 0 */
 				}
 			}
 
@@ -410,10 +462,9 @@ int zcip_main(int argc, char **argv)
 				if (fds[0].revents & POLLERR) {
 					// FIXME: links routinely go down;
 					// this shouldn't necessarily exit.
-					bb_error_msg("%s: poll error", intf);
+					bb_error_msg("iface %s is down", argv_intf);
 					if (ready) {
-						script_av[1] = (char*)"deconfig";
-						run(script_av, intf, &ip);
+						run(argv, "deconfig", &ip);
 					}
 					return EXIT_FAILURE;
 				}
@@ -421,21 +472,19 @@ int zcip_main(int argc, char **argv)
 			}
 
 			// read ARP packet
-			if (recv(fd, &p, sizeof(p), 0) < 0) {
-				why = "recv";
-				goto bad;
+			if (safe_read(sock_fd, &p, sizeof(p)) < 0) {
+				bb_perror_msg_and_die(bb_msg_read_error);
 			}
-			if (p.hdr.ether_type != htons(ETHERTYPE_ARP))
+			if (p.eth.ether_type != htons(ETHERTYPE_ARP))
 				continue;
-
 #ifdef DEBUG
 			{
-				struct ether_addr * sha = (struct ether_addr *) p.arp.arp_sha;
-				struct ether_addr * tha = (struct ether_addr *) p.arp.arp_tha;
-				struct in_addr * spa = (struct in_addr *) p.arp.arp_spa;
-				struct in_addr * tpa = (struct in_addr *) p.arp.arp_tpa;
+				struct ether_addr *sha = (struct ether_addr *) p.arp.arp_sha;
+				struct ether_addr *tha = (struct ether_addr *) p.arp.arp_tha;
+				struct in_addr *spa = (struct in_addr *) p.arp.arp_spa;
+				struct in_addr *tpa = (struct in_addr *) p.arp.arp_tpa;
 				VDBG("%s recv arp type=%d, op=%d,\n",
-					intf, ntohs(p.hdr.ether_type),
+					argv_intf, ntohs(p.eth.ether_type),
 					ntohs(p.arp.arp_op));
 				VDBG("\tsource=%s %s\n",
 					ether_ntoa(sha),
@@ -446,17 +495,28 @@ int zcip_main(int argc, char **argv)
 			}
 #endif
 			if (p.arp.arp_op != htons(ARPOP_REQUEST)
-					&& p.arp.arp_op != htons(ARPOP_REPLY))
+			 && p.arp.arp_op != htons(ARPOP_REPLY)
+			) {
 				continue;
-
-			if (memcmp(p.arp.arp_spa, &ip.s_addr, sizeof(struct in_addr)) == 0 &&
-				memcmp(&eth_addr, &p.arp.arp_sha, ETH_ALEN) != 0) {
-				source_ip_conflict = 1;
 			}
-			if (memcmp(p.arp.arp_tpa, &ip.s_addr, sizeof(struct in_addr)) == 0 &&
-				p.arp.arp_op == htons(ARPOP_REQUEST) &&
-				memcmp(&eth_addr, &p.arp.arp_tha, ETH_ALEN) != 0) {
-				target_ip_conflict = 1;
+
+			source_ip_conflict = 0;
+			target_ip_conflict = 0;
+
+			if (memcmp(&p.arp.arp_sha, &eth_addr, ETH_ALEN) != 0) {
+				if (memcmp(p.arp.arp_spa, &ip.s_addr, sizeof(struct in_addr))) {
+					/* A probe or reply with source_ip == chosen ip */
+					source_ip_conflict = 1;
+				}
+				if (p.arp.arp_op == htons(ARPOP_REQUEST)
+				 && memcmp(p.arp.arp_spa, &null_ip, sizeof(struct in_addr)) == 0
+				 && memcmp(p.arp.arp_tpa, &ip.s_addr, sizeof(struct in_addr)) == 0
+				) {
+					/* A probe with source_ip == 0.0.0.0, target_ip == chosen ip:
+					 * another host trying to claim this ip!
+					 */
+					target_ip_conflict = 1;
+				}
 			}
 
 			VDBG("state = %d, source ip conflict = %d, target ip conflict = %d\n",
@@ -469,13 +529,13 @@ int zcip_main(int argc, char **argv)
 				if (source_ip_conflict || target_ip_conflict) {
 					conflicts++;
 					if (conflicts >= MAX_CONFLICTS) {
-						VDBG("%s ratelimit\n", intf);
+						VDBG("%s ratelimit\n", argv_intf);
 						timeout_ms = RATE_LIMIT_INTERVAL * 1000;
 						state = RATE_LIMIT_PROBE;
 					}
 
 					// restart the whole protocol
-					pick(&ip);
+					ip.s_addr = pick();
 					timeout_ms = 0;
 					nprobes = 0;
 					nclaims = 0;
@@ -487,10 +547,9 @@ int zcip_main(int argc, char **argv)
 					VDBG("monitor conflict -- defending\n");
 					state = DEFEND;
 					timeout_ms = DEFEND_INTERVAL * 1000;
-					arp(fd, &saddr,
-							ARPOP_REQUEST,
-							&eth_addr, ip,
-							&eth_addr, ip);
+					arp(/* ARPOP_REQUEST, */
+						/* &eth_addr, */ ip,
+						&eth_addr, ip);
 				}
 				break;
 			case DEFEND:
@@ -499,11 +558,10 @@ int zcip_main(int argc, char **argv)
 					state = PROBE;
 					VDBG("defend conflict -- starting over\n");
 					ready = 0;
-					script_av[1] = (char*)"deconfig";
-					run(script_av, intf, &ip);
+					run(argv, "deconfig", &ip);
 
 					// restart the whole protocol
-					pick(&ip);
+					ip.s_addr = pick();
 					timeout_ms = 0;
 					nprobes = 0;
 					nclaims = 0;
@@ -513,20 +571,14 @@ int zcip_main(int argc, char **argv)
 				// Invalid, should never happen.  Restart the whole protocol.
 				VDBG("invalid state -- starting over\n");
 				state = PROBE;
-				pick(&ip);
+				ip.s_addr = pick();
 				timeout_ms = 0;
 				nprobes = 0;
 				nclaims = 0;
 				break;
 			} // switch state
-
 			break; // case 1 (packets arriving)
-		default:
-			why = "poll";
-			goto bad;
 		} // switch poll
-	}
- bad:
-	bb_perror_msg("%s, %s", intf, why);
-	return EXIT_FAILURE;
+	} // while (1)
+#undef argv_intf
 }