Index: head/lib/libstand/Makefile
===================================================================
--- head/lib/libstand/Makefile
+++ head/lib/libstand/Makefile
@@ -141,7 +141,7 @@
 	fstat.c close.c lseek.c open.c read.c write.c readdir.c
 
 # network routines
-SRCS+=	arp.c ether.c inet_ntoa.c in_cksum.c net.c udp.c netif.c rpc.c
+SRCS+=	arp.c ether.c ip.c inet_ntoa.c in_cksum.c net.c udp.c netif.c rpc.c
 
 # network info services:
 SRCS+=	bootp.c rarp.c bootparam.c
Index: head/lib/libstand/ip.c
===================================================================
--- head/lib/libstand/ip.c
+++ head/lib/libstand/ip.c
@@ -0,0 +1,422 @@
+/*
+ * Copyright (c) 1992 Regents of the University of California.
+ * All rights reserved.
+ *
+ * This software was developed by the Computer Systems Engineering group
+ * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
+ * contributed to Berkeley.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+ * The send and receive functions were originally implemented in udp.c and
+ * moved here. Also it is likely some more cleanup can be done, especially
+ * once we will implement the support for tcp.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/queue.h>
+
+#include <string.h>
+
+#include <net/if.h>
+#include <netinet/in.h>
+#include <netinet/if_ether.h>
+#include <netinet/in_systm.h>
+
+#include <netinet/in_pcb.h>
+#include <netinet/ip.h>
+#include <netinet/ip_var.h>
+#include <netinet/udp.h>
+#include <netinet/udp_var.h>
+
+#include "stand.h"
+#include "net.h"
+
+typedef STAILQ_HEAD(ipqueue, ip_queue) ip_queue_t;
+struct ip_queue {
+	void		*ipq_pkt;
+	struct ip	*ipq_hdr;
+	STAILQ_ENTRY(ip_queue) ipq_next;
+};
+
+/*
+ * Fragment re-assembly queue.
+ */
+struct ip_reasm {
+	struct in_addr	ip_src;
+	struct in_addr	ip_dst;
+	uint16_t	ip_id;
+	uint8_t		ip_proto;
+	uint8_t		ip_ttl;
+	size_t		ip_total_size;
+	ip_queue_t	ip_queue;
+	void		*ip_pkt;
+	struct ip	*ip_hdr;
+	STAILQ_ENTRY(ip_reasm) ip_next;
+};
+
+STAILQ_HEAD(ire_list, ip_reasm) ire_list = STAILQ_HEAD_INITIALIZER(ire_list);
+
+/* Caller must leave room for ethernet and ip headers in front!! */
+ssize_t
+sendip(struct iodesc *d, void *pkt, size_t len, uint8_t proto)
+{
+	ssize_t cc;
+	struct ip *ip;
+	u_char *ea;
+
+#ifdef NET_DEBUG
+	if (debug) {
+		printf("sendip: proto: %x d=%p called.\n", proto, (void *)d);
+		if (d) {
+			printf("saddr: %s:%d",
+			    inet_ntoa(d->myip), ntohs(d->myport));
+			printf(" daddr: %s:%d\n",
+			    inet_ntoa(d->destip), ntohs(d->destport));
+		}
+	}
+#endif
+
+	ip = (struct ip *)pkt - 1;
+	len += sizeof(*ip);
+
+	bzero(ip, sizeof(*ip));
+
+	ip->ip_v = IPVERSION;			/* half-char */
+	ip->ip_hl = sizeof(*ip) >> 2;		/* half-char */
+	ip->ip_len = htons(len);
+	ip->ip_p = proto;			/* char */
+	ip->ip_ttl = IPDEFTTL;			/* char */
+	ip->ip_src = d->myip;
+	ip->ip_dst = d->destip;
+	ip->ip_sum = in_cksum(ip, sizeof(*ip));	 /* short, but special */
+
+	if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 ||
+	    netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask))
+		ea = arpwhohas(d, ip->ip_dst);
+	else
+		ea = arpwhohas(d, gateip);
+
+	cc = sendether(d, ip, len, ea, ETHERTYPE_IP);
+	if (cc == -1)
+		return (-1);
+	if (cc != len)
+		panic("sendip: bad write (%zd != %zd)", cc, len);
+	return (cc - sizeof(*ip));
+}
+
+static void
+ip_reasm_free(struct ip_reasm *ipr)
+{
+	struct ip_queue *ipq;
+
+	while ((ipq = STAILQ_FIRST(&ipr->ip_queue)) != NULL) {
+		STAILQ_REMOVE_HEAD(&ipr->ip_queue, ipq_next);
+		free(ipq->ipq_pkt);
+		free(ipq);
+	}
+	free(ipr->ip_pkt);
+	free(ipr);
+}
+
+static int
+ip_reasm_add(struct ip_reasm *ipr, void *pkt, struct ip *ip)
+{
+	struct ip_queue *ipq, *prev, *p;
+
+	if ((ipq = calloc(1, sizeof (*ipq))) == NULL)
+		return (1);
+
+	ipq->ipq_pkt = pkt;
+	ipq->ipq_hdr = ip;
+
+	prev = NULL;
+	STAILQ_FOREACH(p, &ipr->ip_queue, ipq_next) {
+		if ((ntohs(p->ipq_hdr->ip_off) & IP_OFFMASK) <
+		    (ntohs(ip->ip_off) & IP_OFFMASK)) {
+			prev = p;
+			continue;
+		}
+		if (prev == NULL)
+			break;
+
+		STAILQ_INSERT_AFTER(&ipr->ip_queue, prev, ipq, ipq_next);
+		return (0);
+	}
+	STAILQ_INSERT_HEAD(&ipr->ip_queue, ipq, ipq_next);
+	return (0);
+}
+
+/*
+ * Receive a IP packet and validate it is for us.
+ */
+static ssize_t
+readipv4(struct iodesc *d, void **pkt, void **payload, time_t tleft,
+    uint8_t proto)
+{
+	ssize_t n;
+	size_t hlen;
+	struct ether_header *eh;
+	struct ip *ip;
+	struct udphdr *uh;
+	uint16_t etype;		/* host order */
+	char *ptr;
+	struct ip_reasm *ipr;
+	struct ip_queue *ipq, *last;
+
+#ifdef NET_DEBUG
+	if (debug)
+		printf("readip: called\n");
+#endif
+
+	ip = NULL;
+	ptr = NULL;
+	n = readether(d, (void **)&ptr, (void **)&ip, tleft, &etype);
+	if (n == -1 || n < sizeof(*ip) + sizeof(*uh)) {
+		free(ptr);
+		return (-1);
+	}
+
+	/* Ethernet address checks now in readether() */
+
+	/* Need to respond to ARP requests. */
+	if (etype == ETHERTYPE_ARP) {
+		struct arphdr *ah = (void *)ip;
+		if (ah->ar_op == htons(ARPOP_REQUEST)) {
+			/* Send ARP reply */
+			arp_reply(d, ah);
+		}
+		free(ptr);
+		errno = EAGAIN;	/* Call me again. */
+		return (-1);
+	}
+
+	if (etype != ETHERTYPE_IP) {
+#ifdef NET_DEBUG
+		if (debug)
+			printf("readip: not IP. ether_type=%x\n", etype);
+#endif
+		free(ptr);
+		return (-1);
+	}
+
+	/* Check ip header */
+	if (ip->ip_v != IPVERSION ||
+	    ip->ip_p != proto) {	/* half char */
+#ifdef NET_DEBUG
+		if (debug) {
+			printf("readip: IP version or proto. ip_v=%d ip_p=%d\n",
+			    ip->ip_v, ip->ip_p);
+		}
+#endif
+		free(ptr);
+		return (-1);
+	}
+
+	hlen = ip->ip_hl << 2;
+	if (hlen < sizeof(*ip) ||
+	    in_cksum(ip, hlen) != 0) {
+#ifdef NET_DEBUG
+		if (debug)
+			printf("readip: short hdr or bad cksum.\n");
+#endif
+		free(ptr);
+		return (-1);
+	}
+	if (n < ntohs(ip->ip_len)) {
+#ifdef NET_DEBUG
+		if (debug)
+			printf("readip: bad length %d < %d.\n",
+			       (int)n, ntohs(ip->ip_len));
+#endif
+		free(ptr);
+		return (-1);
+	}
+	if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) {
+#ifdef NET_DEBUG
+		if (debug) {
+			printf("readip: bad saddr %s != ", inet_ntoa(d->myip));
+			printf("%s\n", inet_ntoa(ip->ip_dst));
+		}
+#endif
+		free(ptr);
+		return (-1);
+	}
+
+	/* Unfragmented packet. */
+	if ((ntohs(ip->ip_off) & IP_MF) == 0 &&
+	    (ntohs(ip->ip_off) & IP_OFFMASK) == 0) {
+		uh = (struct udphdr *)((uintptr_t)ip + sizeof (*ip));
+		/* If there were ip options, make them go away */
+		if (hlen != sizeof(*ip)) {
+			bcopy(((u_char *)ip) + hlen, uh, uh->uh_ulen - hlen);
+			ip->ip_len = htons(sizeof(*ip));
+			n -= hlen - sizeof(*ip);
+		}
+
+		n = (n > (ntohs(ip->ip_len) - sizeof(*ip))) ?
+		    ntohs(ip->ip_len) - sizeof(*ip) : n;
+		*pkt = ptr;
+		*payload = (void *)((uintptr_t)ip + sizeof(*ip));
+		return (n);
+	}
+
+	STAILQ_FOREACH(ipr, &ire_list, ip_next) {
+		if (ipr->ip_src.s_addr == ip->ip_src.s_addr &&
+		    ipr->ip_dst.s_addr == ip->ip_dst.s_addr &&
+		    ipr->ip_id == ip->ip_id &&
+		    ipr->ip_proto == ip->ip_p)
+			break;
+	}
+
+	/* Allocate new reassembly entry */
+	if (ipr == NULL) {
+		if ((ipr = calloc(1, sizeof (*ipr))) == NULL) {
+			free(ptr);
+			return (-1);
+		}
+
+		ipr->ip_src = ip->ip_src;
+		ipr->ip_dst = ip->ip_dst;
+		ipr->ip_id = ip->ip_id;
+		ipr->ip_proto = ip->ip_p;
+		ipr->ip_ttl = MAXTTL;
+		STAILQ_INIT(&ipr->ip_queue);
+		STAILQ_INSERT_TAIL(&ire_list, ipr, ip_next);
+	}
+
+	if (ip_reasm_add(ipr, ptr, ip) != 0) {
+		STAILQ_REMOVE(&ire_list, ipr, ip_reasm, ip_next);
+		free(ipr);
+		free(ptr);
+		return (-1);
+	}
+
+	if ((ntohs(ip->ip_off) & IP_MF) == 0) {
+		ipr->ip_total_size = (8 * (ntohs(ip->ip_off) & IP_OFFMASK));
+		ipr->ip_total_size += n + sizeof (*ip);
+		ipr->ip_total_size += sizeof (struct ether_header);
+
+		ipr->ip_pkt = malloc(ipr->ip_total_size + 2);
+		if (ipr->ip_pkt == NULL) {
+			STAILQ_REMOVE(&ire_list, ipr, ip_reasm, ip_next);
+			ip_reasm_free(ipr);
+			return (-1);
+		}
+	}
+
+	/*
+	 * If we do not have re-assembly buffer ipr->ip_pkt, we are still
+	 * missing fragments, so just restart the read.
+	 */
+	if (ipr->ip_pkt == NULL) {
+		errno = EAGAIN;
+		return (-1);
+	}
+
+	/*
+	 * Walk the packet list in reassembly queue, if we got all the
+	 * fragments, build the packet.
+	 */
+	n = 0;
+	last = NULL;
+	STAILQ_FOREACH(ipq, &ipr->ip_queue, ipq_next) {
+		if ((ntohs(ipq->ipq_hdr->ip_off) & IP_OFFMASK) != n / 8) {
+			errno = EAGAIN;
+			return (-1);
+		}
+
+		n += ntohs(ipq->ipq_hdr->ip_len) - (ipq->ipq_hdr->ip_hl << 2);
+		last = ipq;
+	}
+	if ((ntohs(last->ipq_hdr->ip_off) & IP_MF) != 0) {
+		errno = EAGAIN;
+		return (-1);
+	}
+
+	ipq = STAILQ_FIRST(&ipr->ip_queue);
+	/* Fabricate ethernet header */
+	eh = (struct ether_header *)((uintptr_t)ipr->ip_pkt + 2);
+	bcopy((void *)((uintptr_t)ipq->ipq_pkt + 2), eh, sizeof (*eh));
+
+	/* Fabricate IP header */
+	ipr->ip_hdr = (struct ip *)((uintptr_t)eh + sizeof (*eh));
+	bcopy(ipq->ipq_hdr, ipr->ip_hdr, sizeof (*ipr->ip_hdr));
+	ipr->ip_hdr->ip_hl = sizeof (*ipr->ip_hdr) >> 2;
+	ipr->ip_hdr->ip_len = htons(n);
+	ipr->ip_hdr->ip_sum = 0;
+	ipr->ip_hdr->ip_sum = in_cksum(ipr->ip_hdr, sizeof (*ipr->ip_hdr));
+
+	n = 0;
+	ptr = (char *)((uintptr_t)ipr->ip_hdr + sizeof (*ipr->ip_hdr));
+	STAILQ_FOREACH(ipq, &ipr->ip_queue, ipq_next) {
+		char *data;
+		size_t len;
+
+		hlen = ipq->ipq_hdr->ip_hl << 2;
+		len = ntohs(ipq->ipq_hdr->ip_len) - hlen;
+		data = (char *)((uintptr_t)ipq->ipq_hdr + hlen);
+
+		bcopy(data, ptr + n, len);
+		n += len;
+	}
+
+	*pkt = ipr->ip_pkt;
+	ipr->ip_pkt = NULL;	/* Avoid free from ip_reasm_free() */
+	*payload = ptr;
+
+	/* Clean up the reassembly list */
+	while ((ipr = STAILQ_FIRST(&ire_list)) != NULL) {
+		STAILQ_REMOVE_HEAD(&ire_list, ip_next);
+		ip_reasm_free(ipr);
+	}
+	return (n);
+}
+
+/*
+ * Receive a IP packet.
+ */
+ssize_t
+readip(struct iodesc *d, void **pkt, void **payload, time_t tleft,
+    uint8_t proto)
+{
+	time_t t;
+	ssize_t ret = -1;
+
+	t = getsecs();
+	while ((getsecs() - t) < tleft) {
+		errno = 0;
+		ret = readipv4(d, pkt, payload, tleft, proto);
+		if (errno != EAGAIN)
+			break;
+	}
+	return (ret);
+}
Index: head/lib/libstand/net.h
===================================================================
--- head/lib/libstand/net.h
+++ head/lib/libstand/net.h
@@ -108,6 +108,8 @@
 			u_char *dea, int etype);
 ssize_t readether(struct iodesc *, void **, void **, time_t, uint16_t *);
 
+ssize_t	sendip(struct iodesc *, void *, size_t, uint8_t);
+ssize_t	readip(struct iodesc *, void **, void **, time_t, uint8_t);
 ssize_t	sendudp(struct iodesc *, void *, size_t);
 ssize_t	readudp(struct iodesc *, void **, void **, time_t);
 ssize_t	sendrecv(struct iodesc *,
Index: head/lib/libstand/udp.c
===================================================================
--- head/lib/libstand/udp.c
+++ head/lib/libstand/udp.c
@@ -62,9 +62,8 @@
 sendudp(struct iodesc *d, void *pkt, size_t len)
 {
 	ssize_t cc;
-	struct ip *ip;
+	struct udpiphdr *ui;
 	struct udphdr *uh;
-	u_char *ea;
 
 #ifdef NET_DEBUG
  	if (debug) {
@@ -78,52 +77,31 @@
 	}
 #endif
 
-	uh = (struct udphdr *)pkt - 1;
-	ip = (struct ip *)uh - 1;
-	len += sizeof(*ip) + sizeof(*uh);
-
-	bzero(ip, sizeof(*ip) + sizeof(*uh));
+	ui = (struct udpiphdr *)pkt - 1;
+	bzero(ui, sizeof(*ui));
 
-	ip->ip_v = IPVERSION;			/* half-char */
-	ip->ip_hl = sizeof(*ip) >> 2;		/* half-char */
-	ip->ip_len = htons(len);
-	ip->ip_p = IPPROTO_UDP;			/* char */
-	ip->ip_ttl = IPDEFTTL;			/* char */
-	ip->ip_src = d->myip;
-	ip->ip_dst = d->destip;
-	ip->ip_sum = in_cksum(ip, sizeof(*ip));	 /* short, but special */
+	uh = (struct udphdr *)pkt - 1;
+	len += sizeof(*uh);
 
 	uh->uh_sport = d->myport;
 	uh->uh_dport = d->destport;
-	uh->uh_ulen = htons(len - sizeof(*ip));
+	uh->uh_ulen = htons(len);
 
-#ifndef UDP_NO_CKSUM
-	{
-		struct udpiphdr *ui;
-		struct ip tip;
+	ui->ui_pr = IPPROTO_UDP;
+	ui->ui_len = uh->uh_ulen;
+	ui->ui_src = d->myip;
+	ui->ui_dst = d->destip;
 
-		/* Calculate checksum (must save and restore ip header) */
-		tip = *ip;
-		ui = (struct udpiphdr *)ip;
-		bzero(&ui->ui_x1, sizeof(ui->ui_x1));
-		ui->ui_len = uh->uh_ulen;
-		uh->uh_sum = in_cksum(ui, len);
-		*ip = tip;
-	}
+#ifndef UDP_NO_CKSUM
+	uh->uh_sum = in_cksum(ui, len + sizeof (struct ip));
 #endif
 
-	if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 ||
-	    netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask))
-		ea = arpwhohas(d, ip->ip_dst);
-	else
-		ea = arpwhohas(d, gateip);
-
-	cc = sendether(d, ip, len, ea, ETHERTYPE_IP);
+	cc = sendip(d, uh, len, IPPROTO_UDP);
 	if (cc == -1)
 		return (-1);
 	if (cc != len)
 		panic("sendudp: bad write (%zd != %zd)", cc, len);
-	return (cc - (sizeof(*ip) + sizeof(*uh)));
+	return (cc - sizeof(*uh));
 }
 
 /*
@@ -133,10 +111,7 @@
 readudp(struct iodesc *d, void **pkt, void **payload, time_t tleft)
 {
 	ssize_t n;
-	size_t hlen;
-	struct ip *ip;
 	struct udphdr *uh;
-	uint16_t etype;		/* host order */
 	void *ptr;
 
 #ifdef NET_DEBUG
@@ -144,84 +119,14 @@
 		printf("readudp: called\n");
 #endif
 
-	ip = NULL;
+	uh = NULL;
 	ptr = NULL;
-	n = readether(d, &ptr, (void **)&ip, tleft, &etype);
-	if (n == -1 || n < sizeof(*ip) + sizeof(*uh)) {
+	n = readip(d, &ptr, (void **)&uh, tleft, IPPROTO_UDP);
+	if (n == -1 || n < sizeof(*uh) || n != ntohs(uh->uh_ulen)) {
 		free(ptr);
 		return (-1);
 	}
 
-	/* Ethernet address checks now in readether() */
-
-	/* Need to respond to ARP requests. */
-	if (etype == ETHERTYPE_ARP) {
-		struct arphdr *ah = (void *)ip;
-		if (ah->ar_op == htons(ARPOP_REQUEST)) {
-			/* Send ARP reply */
-			arp_reply(d, ah);
-		}
-		free(ptr);
-		return (-1);
-	}
-
-	if (etype != ETHERTYPE_IP) {
-#ifdef NET_DEBUG
-		if (debug)
-			printf("readudp: not IP. ether_type=%x\n", etype);
-#endif
-		free(ptr);
-		return (-1);
-	}
-
-	/* Check ip header */
-	if (ip->ip_v != IPVERSION ||
-	    ip->ip_p != IPPROTO_UDP) {	/* half char */
-#ifdef NET_DEBUG
-		if (debug)
-			printf("readudp: IP version or not UDP. ip_v=%d ip_p=%d\n", ip->ip_v, ip->ip_p);
-#endif
-		free(ptr);
-		return (-1);
-	}
-
-	hlen = ip->ip_hl << 2;
-	if (hlen < sizeof(*ip) ||
-	    in_cksum(ip, hlen) != 0) {
-#ifdef NET_DEBUG
-		if (debug)
-			printf("readudp: short hdr or bad cksum.\n");
-#endif
-		free(ptr);
-		return (-1);
-	}
-	if (n < ntohs(ip->ip_len)) {
-#ifdef NET_DEBUG
-		if (debug)
-			printf("readudp: bad length %d < %d.\n",
-			       (int)n, ntohs(ip->ip_len));
-#endif
-		free(ptr);
-		return (-1);
-	}
-	if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) {
-#ifdef NET_DEBUG
-		if (debug) {
-			printf("readudp: bad saddr %s != ", inet_ntoa(d->myip));
-			printf("%s\n", inet_ntoa(ip->ip_dst));
-		}
-#endif
-		free(ptr);
-		return (-1);
-	}
-
-	uh = (struct udphdr *)((uintptr_t)ip + sizeof (*ip));
-	/* If there were ip options, make them go away */
-	if (hlen != sizeof(*ip)) {
-		bcopy(((u_char *)ip) + hlen, uh, uh->uh_ulen - hlen);
-		ip->ip_len = htons(sizeof(*ip));
-		n -= hlen - sizeof(*ip);
-	}
 	if (uh->uh_dport != d->myport) {
 #ifdef NET_DEBUG
 		if (debug)
@@ -235,16 +140,13 @@
 #ifndef UDP_NO_CKSUM
 	if (uh->uh_sum) {
 		struct udpiphdr *ui;
+		struct ip *ip;
 		struct ip tip;
 
 		n = ntohs(uh->uh_ulen) + sizeof(*ip);
-		if (n > RECV_SIZE - ETHER_SIZE) {
-			printf("readudp: huge packet, udp len %d\n", (int)n);
-			free(ptr);
-			return (-1);
-		}
 
 		/* Check checksum (must save and restore ip header) */
+		ip = (struct ip *)uh - 1;
 		tip = *ip;
 		ui = (struct udpiphdr *)ip;
 		bzero(&ui->ui_x1, sizeof(ui->ui_x1));