Import libpcap 0.7.1, from

 http://www.tcpdump.org/release/libpcap-0.7.1.tar.gz

1 files changed, 842 insertions, 107 deletions

diff --git a/contrib/libpcap/inet.c b/contrib/libpcap/inet.c
index 0b5b696..fa97aaf 100644
--- a/contrib/libpcap/inet.c
+++ b/contrib/libpcap/inet.c
@@ -1,3 +1,4 @@
+/* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
 /*
  * Copyright (c) 1994, 1995, 1996, 1997, 1998
  *	The Regents of the University of California.  All rights reserved.
@@ -33,7 +34,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/libpcap/inet.c,v 1.36 2000/09/20 15:10:29 torsten Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/inet.c,v 1.45 2001/10/28 20:40:43 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -61,6 +62,11 @@ struct rtentry;
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#else
+#define INT_MAX		2147483647
+#endif
 #ifdef HAVE_IFADDRS_H
 #include <ifaddrs.h>
 #endif
@@ -73,189 +79,918 @@ struct rtentry;
 
 /* Not all systems have IFF_LOOPBACK */
 #ifdef IFF_LOOPBACK
-#define ISLOOPBACK(p) ((p)->ifr_flags & IFF_LOOPBACK)
-#define ISLOOPBACK_IFA(p) ((p)->ifa_flags & IFF_LOOPBACK)
+#define ISLOOPBACK(name, flags) ((flags) & IFF_LOOPBACK)
 #else
-#define ISLOOPBACK(p) ((p)->ifr_name[0] == 'l' && (p)->ifr_name[1] == 'o' && \
-    (isdigit((p)->ifr_name[2]) || (p)->ifr_name[2] == '\0'))
-#define ISLOOPBACK_IFA(p) ((p)->ifa_name[0] == 'l' && (p)->ifa_name[1] == 'o' && \
-    (isdigit((p)->ifa_name[2]) || (p)->ifa_name[2] == '\0'))
+#define ISLOOPBACK(name, flags) ((name)[0] == 'l' && (name)[1] == 'o' && \
+    (isdigit((unsigned char)((name)[2])) || (name)[2] == '\0'))
 #endif
 
 /*
- * Return the name of a network interface attached to the system, or NULL
- * if none can be found.  The interface must be configured up; the
- * lowest unit number is preferred; loopback is ignored.
+ * This is fun.
+ *
+ * In older BSD systems, socket addresses were fixed-length, and
+ * "sizeof (struct sockaddr)" gave the size of the structure.
+ * All addresses fit within a "struct sockaddr".
+ *
+ * In newer BSD systems, the socket address is variable-length, and
+ * there's an "sa_len" field giving the length of the structure;
+ * this allows socket addresses to be longer than 2 bytes of family
+ * and 14 bytes of data.
+ *
+ * Some commercial UNIXes use the old BSD scheme, and some might use
+ * the new BSD scheme.
+ *
+ * GNU libc uses neither scheme, but has an "SA_LEN()" macro that
+ * determines the size based on the address family.
  */
-char *
-pcap_lookupdev(errbuf)
-	register char *errbuf;
+#ifndef SA_LEN
+#ifdef HAVE_SOCKADDR_SA_LEN
+#define SA_LEN(addr)	((addr)->sa_len)
+#else /* HAVE_SOCKADDR_SA_LEN */
+#define SA_LEN(addr)	(sizeof (struct sockaddr))
+#endif /* HAVE_SOCKADDR_SA_LEN */
+#endif /* SA_LEN */
+
+/*
+ * Description string for the "any" device.
+ */
+static const char any_descr[] = "Pseudo-device that captures on all interfaces";
+
+static struct sockaddr *
+dup_sockaddr(struct sockaddr *sa)
+{
+	struct sockaddr *newsa;
+	unsigned int size;
+	
+	size = SA_LEN(sa);
+	if ((newsa = malloc(size)) == NULL)
+		return (NULL);
+	return (memcpy(newsa, sa, size));
+}
+
+static int
+get_instance(char *name)
+{
+	char *cp, *endcp;
+	int n;
+
+	if (strcmp(name, "any") == 0) {
+		/*
+		 * Give the "any" device an artificially high instance
+		 * number, so it shows up after all other non-loopback
+		 * interfaces.
+		 */
+		return INT_MAX;
+	}
+
+	endcp = name + strlen(name);
+	for (cp = name; cp < endcp && !isdigit((unsigned char)*cp); ++cp)
+		continue;
+
+	if (isdigit((unsigned char)*cp))
+		n = atoi(cp);
+	else
+		n = 0;
+	return (n);
+}
+
+static int
+add_or_find_if(pcap_if_t **curdev_ret, pcap_if_t **alldevs, char *name,
+    u_int flags, const char *description, char *errbuf)
+{
+	pcap_t *p;
+	pcap_if_t *curdev, *prevdev, *nextdev;
+	int this_instance;
+
+	/*
+	 * Can we open this interface for live capture?
+	 */
+	p = pcap_open_live(name, 68, 0, 0, errbuf);
+	if (p == NULL) {
+		/*
+		 * No.  Don't bother including it.
+		 * Don't treat this as an error, though.
+		 */
+		*curdev_ret = NULL;
+		return (0);
+	}
+	pcap_close(p);
+
+	/*
+	 * Is there already an entry in the list for this interface?
+	 */
+	for (curdev = *alldevs; curdev != NULL; curdev = curdev->next) {
+		if (strcmp(name, curdev->name) == 0)
+			break;	/* yes, we found it */
+	}
+	if (curdev == NULL) {
+		/*
+		 * No, we didn't find it.
+		 * Allocate a new entry.
+		 */
+		curdev = malloc(sizeof(pcap_if_t));
+		if (curdev == NULL) {
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+			    "malloc: %s", pcap_strerror(errno));
+			return (-1);
+		}
+		
+		/*
+		 * Fill in the entry.
+		 */
+		curdev->next = NULL;
+		curdev->name = malloc(strlen(name) + 1);
+		strcpy(curdev->name, name);
+		if (description != NULL) {
+			/*
+			 * We have a description for this interface.
+			 */
+			curdev->description = malloc(strlen(description) + 1);
+			strcpy(curdev->description, description);
+		} else {
+			/*
+			 * We don't.
+			 */
+			curdev->description = NULL;
+		}
+		curdev->addresses = NULL;	/* list starts out as empty */
+		curdev->flags = 0;
+		if (ISLOOPBACK(name, flags))
+			curdev->flags |= PCAP_IF_LOOPBACK;
+
+		/*
+		 * Add it to the list, in the appropriate location.
+		 * First, get the instance number of this interface.
+		 */
+		this_instance = get_instance(name);
+
+		/*
+		 * Now look for the last interface with an instance number
+		 * less than or equal to the new interface's instance
+		 * number - except that non-loopback interfaces are
+		 * arbitrarily treated as having interface numbers less
+		 * than those of loopback interfaces, so the loopback
+		 * interfaces are put at the end of the list.
+		 *
+		 * We start with "prevdev" being NULL, meaning we're before
+		 * the first element in the list.
+		 */
+		prevdev = NULL;
+		for (;;) {
+			/*
+			 * Get the interface after this one.
+			 */
+			if (prevdev == NULL) {
+				/*
+				 * The next element is the first element.
+				 */
+				nextdev = *alldevs;
+			} else
+				nextdev = prevdev->next;
+
+			/*
+			 * Are we at the end of the list?
+			 */
+			if (nextdev == NULL) {
+				/*
+				 * Yes - we have to put the new entry
+				 * after "prevdev".
+				 */
+				break;
+			}
+
+			/*
+			 * Is the new interface a non-loopback interface
+			 * and the next interface a loopback interface?
+			 */
+			if (!(curdev->flags & PCAP_IF_LOOPBACK) &&
+			    (nextdev->flags & PCAP_IF_LOOPBACK)) {
+				/*
+				 * Yes, we should put the new entry
+				 * before "nextdev", i.e. after "prevdev".
+				 */
+				break;
+			}
+
+			/*
+			 * Is the new interface's instance number less
+			 * than the next interface's instance number,
+			 * and is it the case that the new interface is a
+			 * non-loopback interface or the next interface is
+			 * a loopback interface?
+			 *
+			 * (The goal of both loopback tests is to make
+			 * sure that we never put a loopback interface
+			 * before any non-loopback interface and that we
+			 * always put a non-loopback interface before all
+			 * loopback interfaces.)
+			 */
+			if (this_instance < get_instance(nextdev->name) &&
+			    (!(curdev->flags & PCAP_IF_LOOPBACK) ||
+			       (nextdev->flags & PCAP_IF_LOOPBACK))) {
+				/*
+				 * Yes - we should put the new entry
+				 * before "nextdev", i.e. after "prevdev".
+				 */
+				break;
+			}
+
+			prevdev = nextdev;
+		}
+
+		/*
+		 * Insert before "nextdev".
+		 */
+		curdev->next = nextdev;
+
+		/*
+		 * Insert after "prevdev" - unless "prevdev" is null,
+		 * in which case this is the first interface.
+		 */
+		if (prevdev == NULL) {
+			/*
+			 * This is the first interface.  Pass back a
+			 * pointer to it, and put "curdev" before
+			 * "nextdev".
+			 */
+			*alldevs = curdev;
+		} else
+			prevdev->next = curdev;
+	}
+	
+	*curdev_ret = curdev;
+	return (0);
+}
+
+static int
+add_addr_to_iflist(pcap_if_t **alldevs, char *name, u_int flags,
+    struct sockaddr *addr, struct sockaddr *netmask,
+    struct sockaddr *broadaddr, struct sockaddr *dstaddr, char *errbuf)
 {
+	pcap_if_t *curdev;
+	pcap_addr_t *curaddr, *prevaddr, *nextaddr;
+
+	if (add_or_find_if(&curdev, alldevs, name, flags, NULL, errbuf) == -1) {
+		/*
+		 * Error - give up.
+		 */
+		return (-1);
+	}
+	if (curdev == NULL) {
+		/*
+		 * Device wasn't added because it can't be opened.
+		 * Not a fatal error.
+		 */
+		return (0);
+	}
+
+	/*
+	 * "curdev" is an entry for this interface; add an entry for this
+	 * address to its list of addresses.
+	 *
+	 * Allocate the new entry and fill it in.
+	 */
+	curaddr = malloc(sizeof(pcap_addr_t));
+	if (curaddr == NULL) {
+		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+		    "malloc: %s", pcap_strerror(errno));
+		return (-1);
+	}
+
+	curaddr->next = NULL;
+	if (addr != NULL) {
+		curaddr->addr = dup_sockaddr(addr);
+		if (curaddr->addr == NULL) {
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+			    "malloc: %s", pcap_strerror(errno));
+			free(curaddr);
+			return (-1);
+		}
+	} else
+		curaddr->addr = NULL;
+
+	if (netmask != NULL) {
+		curaddr->netmask = dup_sockaddr(netmask);
+		if (curaddr->netmask == NULL) {
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+			    "malloc: %s", pcap_strerror(errno));
+			free(curaddr);
+			return (-1);
+		}
+	} else
+		curaddr->netmask = NULL;
+		
+	if (broadaddr != NULL) {
+		curaddr->broadaddr = dup_sockaddr(broadaddr);
+		if (curaddr->broadaddr == NULL) {
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+			    "malloc: %s", pcap_strerror(errno));
+			free(curaddr);
+			return (-1);
+		}
+	} else
+		curaddr->broadaddr = NULL;
+		
+	if (dstaddr != NULL) {
+		curaddr->dstaddr = dup_sockaddr(dstaddr);
+		if (curaddr->dstaddr == NULL) {
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+			    "malloc: %s", pcap_strerror(errno));
+			free(curaddr);
+			return (-1);
+		}
+	} else
+		curaddr->dstaddr = NULL;
+		
+	/*
+	 * Find the end of the list of addresses.
+	 */
+	for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
+		nextaddr = prevaddr->next;
+		if (nextaddr == NULL) {
+			/*
+			 * This is the end of the list.
+			 */
+			break;
+		}
+	}
+
+	if (prevaddr == NULL) {
+		/*
+		 * The list was empty; this is the first member.
+		 */
+		curdev->addresses = curaddr;
+	} else {
+		/*
+		 * "prevaddr" is the last member of the list; append
+		 * this member to it.
+		 */
+		prevaddr->next = curaddr;
+	}
+
+	return (0);
+}
+
+static int
+pcap_add_if(pcap_if_t **devlist, char *name, u_int flags,
+    const char *description, char *errbuf)
+{
+	pcap_if_t *curdev;
+
+	return (add_or_find_if(&curdev, devlist, name, flags, description,
+	    errbuf));
+}
+
+/*
+ * Get a list of all interfaces that are up and that we can open.
+ * Returns -1 on error, 0 otherwise.
+ * The list, as returned through "alldevsp", may be null if no interfaces
+ * were up and could be opened.
+ */
 #ifdef HAVE_IFADDRS_H
-	struct ifaddrs *ifap, *ifa, *mp;
-	int n, minunit;
-	char *cp;
-	static char device[IF_NAMESIZE + 1];
+int
+pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
+{
+	pcap_if_t *devlist = NULL;
+	struct ifaddrs *ifap, *ifa;
+	struct sockaddr *broadaddr, *dstaddr;
+	int ret = 0;
 
+	/*
+	 * Get the list of interface addresses.
+	 *
+	 * Note: this won't return information about interfaces
+	 * with no addresses; are there any such interfaces
+	 * that would be capable of receiving packets?
+	 * (Interfaces incapable of receiving packets aren't
+	 * very interesting from libpcap's point of view.)
+	 *
+	 * LAN interfaces will probably have link-layer
+	 * addresses; I don't know whether all implementations
+	 * of "getifaddrs()" now, or in the future, will return
+	 * those.
+	 */
 	if (getifaddrs(&ifap) != 0) {
 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 		    "getifaddrs: %s", pcap_strerror(errno));
-		return NULL;
+		return (-1);
+	}
+	for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
+		/*
+		 * Is this interface up?
+		 */
+		if (!(ifa->ifa_flags & IFF_UP)) {
+			/*
+			 * No, so don't add it to the list.
+			 */
+			continue;
+		}
+
+		/*
+		 * "ifa_broadaddr" may be non-null even on
+		 * non-broadcast interfaces; "ifa_dstaddr"
+		 * was, on at least one FreeBSD 4.1 system,
+		 * non-null on a non-point-to-point
+		 * interface.
+		 */
+		if (ifa->ifa_flags & IFF_BROADCAST)
+			broadaddr = ifa->ifa_broadaddr;
+		else
+			broadaddr = NULL;
+		if (ifa->ifa_flags & IFF_POINTOPOINT)
+			dstaddr = ifa->ifa_dstaddr;
+		else
+			dstaddr = NULL;
+
+		/*
+		 * Add information for this address to the list.
+		 */
+		if (add_addr_to_iflist(&devlist, ifa->ifa_name,
+		    ifa->ifa_flags, ifa->ifa_addr, ifa->ifa_netmask,
+		    broadaddr, dstaddr, errbuf) < 0) {
+			ret = -1;
+			break;
+		}
 	}
 
-	mp = NULL;
-	minunit = 666;
-	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
-		const char *endcp;
+	freeifaddrs(ifap);
 
-		if ((ifa->ifa_flags & IFF_UP) == 0 || ISLOOPBACK_IFA(ifa))
-			continue;
+	if (ret != -1) {
+		/*
+		 * We haven't had any errors yet; add the "any" device,
+		 * if we can open it.
+		 */
+		if (pcap_add_if(&devlist, "any", 0, any_descr, errbuf) < 0)
+			ret = -1;
+	}
+
+	if (ret == -1) {
+		/*
+		 * We had an error; free the list we've been constructing.
+		 */
+		if (devlist != NULL) {
+			pcap_freealldevs(devlist);
+			devlist = NULL;
+		}
+	}
+
+	*alldevsp = devlist;
+	return (ret);
+}
+#else /* HAVE_IFADDRS_H */
+#ifdef HAVE_PROC_NET_DEV
+/*
+ * Get from "/proc/net/dev" all interfaces listed there; if they're
+ * already in the list of interfaces we have, that won't add another
+ * instance, but if they're not, that'll add them.
+ *
+ * We don't bother getting any addresses for them; it appears you can't
+ * use SIOCGIFADDR on Linux to get IPv6 addresses for interfaces, and,
+ * although some other types of addresses can be fetched with SIOCGIFADDR,
+ * we don't bother with them for now.
+ *
+ * We also don't fail if we couldn't open "/proc/net/dev"; we just leave
+ * the list of interfaces as is.
+ */
+static int
+scan_proc_net_dev(pcap_if_t **devlistp, int fd, char *errbuf)
+{
+	FILE *proc_net_f;
+	char linebuf[512];
+	int linenum;
+	unsigned char *p;
+	char name[512];	/* XXX - pick a size */
+	char *q, *saveq;
+	struct ifreq ifrflags;
+	int ret = 0;
 
-		endcp = ifa->ifa_name + strlen(ifa->ifa_name);
-		for (cp = ifa->ifa_name; cp < endcp && !isdigit(*cp); ++cp)
+	proc_net_f = fopen("/proc/net/dev", "r");
+	if (proc_net_f == NULL)
+		return (0);
+
+	for (linenum = 1;
+	    fgets(linebuf, sizeof linebuf, proc_net_f) != NULL; linenum++) {
+		/*
+		 * Skip the first two lines - they're headers.
+		 */
+		if (linenum <= 2)
 			continue;
 
-		if (isdigit (*cp)) {
-			n = atoi(cp);
-		} else {
-			n = 0;
+		p = &linebuf[0];
+
+		/*
+		 * Skip leading white space.
+		 */
+		while (*p != '\0' && isspace(*p))
+			p++;
+		if (*p == '\0' || *p == '\n')
+			continue;	/* blank line */
+
+		/*
+		 * Get the interface name.
+		 */
+		q = &name[0];
+		while (*p != '\0' && !isspace(*p)) {
+			if (*p == ':') {
+				/*
+				 * This could be the separator between a
+				 * name and an alias number, or it could be
+				 * the separator between a name with no 
+				 * alias number and the next field.
+				 *
+				 * If there's a colon after digits, it
+				 * separates the name and the alias number,
+				 * otherwise it separates the name and the
+				 * next field.
+				 */
+				saveq = q;
+				while (isdigit(*p))
+					*q++ = *p++;
+				if (*p != ':') {
+					/*
+					 * That was the next field,
+					 * not the alias number.
+					 */
+					q = saveq;
+				}
+				break;
+			} else
+				*q++ = *p++;
+		}
+		*q = '\0';
+
+		/*
+		 * Get the flags for this interface, and skip it if
+		 * it's not up.
+		 */
+		strncpy(ifrflags.ifr_name, name, sizeof(ifrflags.ifr_name));
+		if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifrflags) < 0) {
+			if (errno == ENXIO)
+				continue;
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+			    "SIOCGIFFLAGS: %.*s: %s",
+			    (int)sizeof(ifrflags.ifr_name),
+			    ifrflags.ifr_name,
+			    pcap_strerror(errno));
+			ret = -1;
+			break;
 		}
-		if (n < minunit) {
-			minunit = n;
-			mp = ifa;
+		if (!(ifrflags.ifr_flags & IFF_UP))
+			continue;
+
+		/*
+		 * Add an entry for this interface, with no addresses.
+		 */
+		if (pcap_add_if(devlistp, name, ifrflags.ifr_flags, NULL,
+		    errbuf) == -1) {
+			/*
+			 * Failure.
+			 */
+			ret = -1;
+			break;
 		}
 	}
-	if (mp == NULL) {
-		(void)strlcpy(errbuf, "no suitable device found",
-		    PCAP_ERRBUF_SIZE);
-#ifdef HAVE_FREEIFADDRS
-		freeifaddrs(ifap);
-#else
-		free(ifap);
-#endif
-		return (NULL);
+	if (ret != -1) {
+		/*
+		 * Well, we didn't fail for any other reason; did we
+		 * fail due to an error reading the file?
+		 */
+		if (ferror(proc_net_f)) {
+			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+			    "Error reading /proc/net/dev: %s",
+			    pcap_strerror(errno));
+			ret = -1;
+		}
 	}
 
-	(void)strlcpy(device, mp->ifa_name, sizeof(device));
-#ifdef HAVE_FREEIFADDRS
-	freeifaddrs(ifap);
-#else
-	free(ifap);
-#endif
-	return (device);
-#else
-	register int fd, minunit, n;
-	register char *cp;
-	register struct ifreq *ifrp, *ifend, *ifnext, *mp;
+	(void)fclose(proc_net_f);
+	return (ret);
+}
+#endif /* HAVE_PROC_NET_DEV */
+
+int
+pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
+{
+	pcap_if_t *devlist = NULL;
+	register int fd;
+	register struct ifreq *ifrp, *ifend, *ifnext;
+	int n;
 	struct ifconf ifc;
-	char *buf;
-	struct ifreq ifr;
-	static char device[sizeof(ifrp->ifr_name) + 1];
+	char *buf = NULL;
 	unsigned buf_size;
+	struct ifreq ifrflags, ifrnetmask, ifrbroadaddr, ifrdstaddr;
+	struct sockaddr *netmask, *broadaddr, *dstaddr;
+	int ret = 0;
 
+	/*
+	 * Create a socket from which to fetch the list of interfaces.
+	 */
 	fd = socket(AF_INET, SOCK_DGRAM, 0);
 	if (fd < 0) {
 		(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 		    "socket: %s", pcap_strerror(errno));
-		return (NULL);
+		return (-1);
 	}
 
+	/*
+	 * Start with an 8K buffer, and keep growing the buffer until
+	 * we get the entire interface list or fail to get it for some
+	 * reason other than EINVAL (which is presumed here to mean
+	 * "buffer is too small").
+	 */
 	buf_size = 8192;
-
 	for (;;) {
-		buf = malloc (buf_size);
+		buf = malloc(buf_size);
 		if (buf == NULL) {
-			close (fd);
 			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
-			    "out of memory");
-			return (NULL);
+			    "malloc: %s", pcap_strerror(errno));
+			(void)close(fd);
+			return (-1);
 		}
 
 		ifc.ifc_len = buf_size;
 		ifc.ifc_buf = buf;
-		memset (buf, 0, buf_size);
+		memset(buf, 0, buf_size);
 		if (ioctl(fd, SIOCGIFCONF, (char *)&ifc) < 0
 		    && errno != EINVAL) {
-			free (buf);
 			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 			    "SIOCGIFCONF: %s", pcap_strerror(errno));
 			(void)close(fd);
-			return (NULL);
+			free(buf);
+			return (-1);
 		}
 		if (ifc.ifc_len < buf_size)
 			break;
-		free (buf);
+		free(buf);
 		buf_size *= 2;
 	}
 
 	ifrp = (struct ifreq *)buf;
 	ifend = (struct ifreq *)(buf + ifc.ifc_len);
 
-	mp = NULL;
-	minunit = 666;
 	for (; ifrp < ifend; ifrp = ifnext) {
-		const char *endcp;
-
-#ifdef HAVE_SOCKADDR_SA_LEN
-		n = ifrp->ifr_addr.sa_len + sizeof(ifrp->ifr_name);
+		n = SA_LEN(&ifrp->ifr_addr) + sizeof(ifrp->ifr_name);
 		if (n < sizeof(*ifrp))
 			ifnext = ifrp + 1;
 		else
 			ifnext = (struct ifreq *)((char *)ifrp + n);
-		if (ifrp->ifr_addr.sa_family != AF_INET)
-			continue;
-#else
-		ifnext = ifrp + 1;
-#endif
+
 		/*
-		 * Need a template to preserve address info that is
-		 * used below to locate the next entry.  (Otherwise,
-		 * SIOCGIFFLAGS stomps over it because the requests
-		 * are returned in a union.)
+		 * Get the flags for this interface, and skip it if it's
+		 * not up.
 		 */
-		strncpy(ifr.ifr_name, ifrp->ifr_name, sizeof(ifr.ifr_name));
-		if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifr) < 0) {
+		strncpy(ifrflags.ifr_name, ifrp->ifr_name,
+		    sizeof(ifrflags.ifr_name));
+		if (ioctl(fd, SIOCGIFFLAGS, (char *)&ifrflags) < 0) {
 			if (errno == ENXIO)
 				continue;
 			(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
 			    "SIOCGIFFLAGS: %.*s: %s",
-			    (int)sizeof(ifr.ifr_name), ifr.ifr_name,
+			    (int)sizeof(ifrflags.ifr_name),
+			    ifrflags.ifr_name,
 			    pcap_strerror(errno));
-			(void)close(fd);
-			free (buf);
-			return (NULL);
+			ret = -1;
+			break;
 		}
-
-		/* Must be up and not the loopback */
-		if ((ifr.ifr_flags & IFF_UP) == 0 || ISLOOPBACK(&ifr))
+		if (!(ifrflags.ifr_flags & IFF_UP))
 			continue;
 
-		endcp = ifrp->ifr_name + strlen(ifrp->ifr_name);
-		for (cp = ifrp->ifr_name; cp < endcp && !isdigit(*cp); ++cp)
-			continue;
-		
-		if (isdigit (*cp)) {
-			n = atoi(cp);
+		/*
+		 * Get the netmask for this address on this interface.
+		 */
+		strncpy(ifrnetmask.ifr_name, ifrp->ifr_name,
+		    sizeof(ifrnetmask.ifr_name));
+		memcpy(&ifrnetmask.ifr_addr, &ifrp->ifr_addr,
+		    sizeof(ifrnetmask.ifr_addr));
+		if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifrnetmask) < 0) {
+			if (errno == EADDRNOTAVAIL) {
+				/*
+				 * Not available.
+				 */
+				netmask = NULL;
+			} else {
+				(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+				    "SIOCGIFNETMASK: %.*s: %s",
+				    (int)sizeof(ifrnetmask.ifr_name),
+				    ifrnetmask.ifr_name,
+				    pcap_strerror(errno));
+				ret = -1;
+				break;
+			}
+		} else
+			netmask = &ifrnetmask.ifr_addr;
+
+		/*
+		 * Get the broadcast address for this address on this
+		 * interface (if any).
+		 */
+		if (ifrflags.ifr_flags & IFF_BROADCAST) {
+			strncpy(ifrbroadaddr.ifr_name, ifrp->ifr_name,
+			    sizeof(ifrbroadaddr.ifr_name));
+			memcpy(&ifrbroadaddr.ifr_addr, &ifrp->ifr_addr,
+			    sizeof(ifrbroadaddr.ifr_addr));
+			if (ioctl(fd, SIOCGIFBRDADDR,
+			    (char *)&ifrbroadaddr) < 0) {
+				if (errno == EADDRNOTAVAIL) {
+					/*
+					 * Not available.
+					 */
+					broadaddr = NULL;
+				} else {
+					(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+					    "SIOCGIFBRDADDR: %.*s: %s",
+					    (int)sizeof(ifrbroadaddr.ifr_name),
+					    ifrbroadaddr.ifr_name,
+					    pcap_strerror(errno));
+					ret = -1;
+					break;
+				}
+			} else
+				broadaddr = &ifrbroadaddr.ifr_broadaddr;
 		} else {
-			n = 0;
+			/*
+			 * Not a broadcast interface, so no broadcast
+			 * address.
+			 */
+			broadaddr = NULL;
 		}
-		if (n < minunit) {
-			minunit = n;
-			mp = ifrp;
+
+		/*
+		 * Get the destination address for this address on this
+		 * interface (if any).
+		 */
+		if (ifrflags.ifr_flags & IFF_POINTOPOINT) {
+			strncpy(ifrdstaddr.ifr_name, ifrp->ifr_name,
+			    sizeof(ifrdstaddr.ifr_name));
+			memcpy(&ifrdstaddr.ifr_addr, &ifrp->ifr_addr,
+			    sizeof(ifrdstaddr.ifr_addr));
+			if (ioctl(fd, SIOCGIFDSTADDR,
+			    (char *)&ifrdstaddr) < 0) {
+				if (errno == EADDRNOTAVAIL) {
+					/*
+					 * Not available.
+					 */
+					dstaddr = NULL;
+				} else {
+					(void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
+					    "SIOCGIFDSTADDR: %.*s: %s",
+					    (int)sizeof(ifrdstaddr.ifr_name),
+					    ifrdstaddr.ifr_name,
+					    pcap_strerror(errno));
+					ret = -1;
+					break;
+				}
+			} else
+				dstaddr = &ifrdstaddr.ifr_dstaddr;
+		} else
+			dstaddr = NULL;
+
+		/*
+		 * Add information for this address to the list.
+		 */
+		if (add_addr_to_iflist(&devlist, ifrp->ifr_name,
+		    ifrflags.ifr_flags, &ifrp->ifr_addr,
+		    netmask, broadaddr, dstaddr, errbuf) < 0) {
+			ret = -1;
+			break;
 		}
 	}
+	free(buf);
+
+#ifdef HAVE_PROC_NET_DEV
+	if (ret != -1) {
+		/*
+		 * We haven't had any errors yet; now read "/proc/net/dev",
+		 * and add to the list of interfaces all interfaces listed
+		 * there that we don't already have, because, on Linux,
+		 * SIOCGIFCONF reports only interfaces with IPv4 addresses,
+		 * so you need to read "/proc/net/dev" to get the names of
+		 * the rest of the interfaces.
+		 */
+		ret = scan_proc_net_dev(&devlist, fd, errbuf);
+	}
+#endif
 	(void)close(fd);
-	if (mp == NULL) {
+
+	if (ret != -1) {
+		/*
+		 * We haven't had any errors yet; add the "any" device,
+		 * if we can open it.
+		 */
+		if (pcap_add_if(&devlist, "any", 0, any_descr, errbuf) < 0) {
+			/*
+			 * Oops, we had a fatal error.
+			 */
+			ret = -1;
+		}
+	}
+
+	if (ret == -1) {
+		/*
+		 * We had an error; free the list we've been constructing.
+		 */
+		if (devlist != NULL) {
+			pcap_freealldevs(devlist);
+			devlist = NULL;
+		}
+	}
+
+	*alldevsp = devlist;
+	return (ret);
+}
+#endif /* HAVE_IFADDRS_H */
+
+/*
+ * Free a list of interfaces.
+ */
+void
+pcap_freealldevs(pcap_if_t *alldevs)
+{
+	pcap_if_t *curdev, *nextdev;
+	pcap_addr_t *curaddr, *nextaddr;
+
+	for (curdev = alldevs; curdev != NULL; curdev = nextdev) {
+		nextdev = curdev->next;
+
+		/*
+		 * Free all addresses.
+		 */
+		for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) {
+			nextaddr = curaddr->next;
+			if (curaddr->addr)
+				free(curaddr->addr);
+			if (curaddr->netmask)
+				free(curaddr->netmask);
+			if (curaddr->broadaddr)
+				free(curaddr->broadaddr);
+			if (curaddr->dstaddr)
+				free(curaddr->dstaddr);
+			free(curaddr);
+		}
+
+		/*
+		 * Free the name string.
+		 */
+		free(curdev->name);
+
+		/*
+		 * Free the description string, if any.
+		 */
+		if (curdev->description != NULL)
+			free(curdev->description);
+
+		/*
+		 * Free the interface.
+		 */
+		free(curdev);
+	}
+}
+
+/*
+ * Return the name of a network interface attached to the system, or NULL
+ * if none can be found.  The interface must be configured up; the
+ * lowest unit number is preferred; loopback is ignored.
+ */
+char *
+pcap_lookupdev(errbuf)
+	register char *errbuf;
+{
+	pcap_if_t *alldevs;
+/* for old BSD systems, including bsdi3 */
+#ifndef IF_NAMESIZE
+#define IF_NAMESIZE IFNAMSIZ
+#endif
+	static char device[IF_NAMESIZE + 1];
+	char *ret;
+
+	if (pcap_findalldevs(&alldevs, errbuf) == -1)
+		return (NULL);
+	
+	if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) {
+		/*
+		 * There are no devices on the list, or the first device
+		 * on the list is a loopback device, which means there
+		 * are no non-loopback devices on the list.  This means
+		 * we can't return any device.
+		 *
+		 * XXX - why not return a loopback device?  If we can't
+		 * capture on it, it won't be on the list, and if it's
+		 * on the list, there aren't any non-loopback devices,
+		 * so why not just supply it as the default device?
+		 */
 		(void)strlcpy(errbuf, "no suitable device found",
 		    PCAP_ERRBUF_SIZE);
-		free(buf);
-		return (NULL);
+		ret = NULL;
+	} else {
+		/*
+		 * Return the name of the first device on the list.
+		 */
+		(void)strlcpy(device, alldevs->name, sizeof(device));
+		ret = device;
 	}
 
-	(void)strlcpy(device, mp->ifr_name, sizeof(device));
-	free(buf);
-	return (device);
-#endif
+	pcap_freealldevs(alldevs);
+	return (ret);
 }
 
 int