diff -up dhcp-3.1.0/common/nit.c.xen dhcp-3.1.0/common/nit.c

--- dhcp-3.1.0/common/nit.c.xen	2007-05-23 19:30:32.000000000 -0400

+++ dhcp-3.1.0/common/nit.c	2007-10-22 16:12:27.000000000 -0400

@@ -371,7 +371,7 @@ ssize_t receive_packet (interface, buf, 

 	/* Decode the IP and UDP headers... */

 	offset = decode_udp_ip_header (interface, ibuf, bufix,

-				       from, length, &paylen);

+				       from, length, &paylen, 0);

 	/* If the IP or UDP checksum was bad, skip the packet... */

 	if (offset < 0)

diff -up dhcp-3.1.0/common/dlpi.c.xen dhcp-3.1.0/common/dlpi.c

--- dhcp-3.1.0/common/dlpi.c.xen	2007-05-23 19:30:32.000000000 -0400

+++ dhcp-3.1.0/common/dlpi.c	2007-10-22 16:12:11.000000000 -0400

@@ -680,7 +680,7 @@ ssize_t receive_packet (interface, buf, 

 	length -= offset;

 #endif

 	offset = decode_udp_ip_header (interface, dbuf, bufix,

-				       from, length, &paylen);

+				       from, length, &paylen, 0);

 	/* If the IP or UDP checksum was bad, skip the packet... */

 	if (offset < 0) {

diff -up dhcp-3.1.0/common/upf.c.xen dhcp-3.1.0/common/upf.c

--- dhcp-3.1.0/common/upf.c.xen	2007-05-23 19:30:32.000000000 -0400

+++ dhcp-3.1.0/common/upf.c	2007-10-22 16:12:52.000000000 -0400

@@ -322,7 +322,7 @@ ssize_t receive_packet (interface, buf, 

 	/* Decode the IP and UDP headers... */

 	offset = decode_udp_ip_header (interface, ibuf, bufix,

-				       from, length, &paylen);

+				       from, length, &paylen, 0);

 	/* If the IP or UDP checksum was bad, skip the packet... */

 	if (offset < 0)

diff -up dhcp-3.1.0/common/lpf.c.xen dhcp-3.1.0/common/lpf.c

--- dhcp-3.1.0/common/lpf.c.xen	2007-10-22 16:11:12.000000000 -0400

+++ dhcp-3.1.0/common/lpf.c	2007-10-22 16:15:24.000000000 -0400

@@ -34,16 +34,31 @@ static char copyright[] =

 #include "dhcpd.h"

 #if defined (USE_LPF_SEND) || defined (USE_LPF_RECEIVE)

 #include <sys/ioctl.h>

+#include <sys/socket.h>

 #include <sys/uio.h>

 #include <asm/types.h>

 #include <linux/filter.h>

 #include <linux/if_ether.h>

+#include <linux/if_packet.h>

 #include <netinet/in_systm.h>

 #include "includes/netinet/ip.h"

 #include "includes/netinet/udp.h"

 #include "includes/netinet/if_ether.h"

+#ifndef PACKET_AUXDATA

+#define PACKET_AUXDATA 8

+

+struct tpacket_auxdata

+{

+	__u32		tp_status;

+	__u32		tp_len;

+	__u32		tp_snaplen;

+	__u16		tp_mac;

+	__u16		tp_net;

+};

+#endif

+

 /* Reinitializes the specified interface after an address change.   This

    is not required for packet-filter APIs. */

@@ -71,10 +86,14 @@ int if_register_lpf (info)

 	int sock;

 	char filename[50];

 	int b;

-	struct sockaddr sa;

+	union {

+		struct sockaddr_ll ll;

+		struct sockaddr common;

+	} sa;

+	struct ifreq ifr;

 	/* Make an LPF socket. */

-	if ((sock = socket(PF_PACKET, SOCK_PACKET,

+	if ((sock = socket(PF_PACKET, SOCK_RAW,

 			   htons((short)ETH_P_ALL))) < 0) {

 		if (errno == ENOPROTOOPT || errno == EPROTONOSUPPORT ||

 		    errno == ESOCKTNOSUPPORT || errno == EPFNOSUPPORT ||

@@ -89,11 +108,16 @@ int if_register_lpf (info)

 		log_fatal ("Open a socket for LPF: %m");

 	}

+	memset (&ifr, 0, sizeof ifr);

+	strncpy (ifr.ifr_name, (const char *)info -> ifp, sizeof ifr.ifr_name);

+	if (ioctl (sock, SIOCGIFINDEX, &ifr))

+		log_fatal ("Failed to get interface index: %m");

+

 	/* Bind to the interface name */

 	memset (&sa, 0, sizeof sa);

-	sa.sa_family = AF_PACKET;

-	strncpy (sa.sa_data, (const char *)info -> ifp, sizeof sa.sa_data);

-	if (bind (sock, &sa, sizeof sa)) {

+	sa.ll.sll_family = AF_PACKET;

+	sa.ll.sll_ifindex = ifr.ifr_ifindex;

+	if (bind (sock, &sa.common, sizeof sa)) {

 		if (errno == ENOPROTOOPT || errno == EPROTONOSUPPORT ||

 		    errno == ESOCKTNOSUPPORT || errno == EPFNOSUPPORT ||

 		    errno == EAFNOSUPPORT || errno == EINVAL) {

@@ -173,9 +197,18 @@ static void lpf_gen_filter_setup (struct

 void if_register_receive (info)

 	struct interface_info *info;

 {

+	int val;

+

 	/* Open a LPF device and hang it on this interface... */

 	info -> rfdesc = if_register_lpf (info);

+	val = 1;

+	if (setsockopt (info -> rfdesc, SOL_PACKET, PACKET_AUXDATA, &val,

+			sizeof val) < 0) {

+		if (errno != ENOPROTOOPT)

+			log_fatal ("Failed to set auxiliary packet data: %m");

+	}

+

 #if defined (HAVE_TR_SUPPORT)

 	if (info -> hw_address.hbuf [0] == HTYPE_IEEE802)

 		lpf_tr_filter_setup (info);

@@ -294,7 +327,6 @@ ssize_t send_packet (interface, packet, 

 	double hh [16];

 	double ih [1536 / sizeof (double)];

 	unsigned char *buf = (unsigned char *)ih;

-	struct sockaddr sa;

 	int result;

 	int fudge;

@@ -312,15 +344,7 @@ ssize_t send_packet (interface, packet, 

 				(unsigned char *)raw, len);

 	memcpy (buf + ibufp, raw, len);

-	/* For some reason, SOCK_PACKET sockets can't be connected,

-	   so we have to do a sentdo every time. */

-	memset (&sa, 0, sizeof sa);

-	sa.sa_family = AF_PACKET;

-	strncpy (sa.sa_data,

-		 (const char *)interface -> ifp, sizeof sa.sa_data);

-

-	result = sendto (interface -> wfdesc,

-			 buf + fudge, ibufp + len - fudge, 0, &sa, sizeof sa);

+	result = write (interface -> wfdesc, buf + fudge, ibufp + len - fudge);

 	if (result < 0)

 		log_error ("send_packet: %m");

 	return result;

@@ -338,14 +362,35 @@ ssize_t receive_packet (interface, buf, 

 	int nread;

 	int length = 0;

 	int offset = 0;

+	int nocsum = 0;

 	unsigned char ibuf [1536];

 	unsigned bufix = 0;

 	unsigned paylen;

+	unsigned char cmsgbuf[CMSG_LEN(sizeof(struct tpacket_auxdata))];

+	struct iovec iov = {

+		.iov_base = ibuf,

+		.iov_len = sizeof ibuf,

+	};

+	struct msghdr msg = {

+		.msg_iov = &iov,

+		.msg_iovlen = 1,

+		.msg_control = cmsgbuf,

+		.msg_controllen = sizeof(cmsgbuf),

+	};

+	struct cmsghdr *cmsg;

-	length = read (interface -> rfdesc, ibuf, sizeof ibuf);

+	length = recvmsg (interface -> rfdesc, &msg, 0);

 	if (length <= 0)

 		return length;

+	for (cmsg = CMSG_FIRSTHDR(&msg;; cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {

+		if (cmsg->cmsg_level == SOL_PACKET &&

+		    cmsg->cmsg_type == PACKET_AUXDATA) {

+			struct tpacket_auxdata *aux = (void *)CMSG_DATA(cmsg);

+			nocsum = aux->tp_status & TP_STATUS_CSUMNOTREADY;

+		}

+	}

+

 	bufix = 0;

 	/* Decode the physical header... */

 	offset = decode_hw_header (interface, ibuf, bufix, hfrom);

@@ -362,7 +407,7 @@ ssize_t receive_packet (interface, buf, 

 	/* Decode the IP and UDP headers... */

 	offset = decode_udp_ip_header (interface, ibuf, bufix, from,

-				       (unsigned)length, &paylen);

+				       (unsigned)length, &paylen, nocsum);

 	/* If the IP or UDP checksum was bad, skip the packet... */

 	if (offset < 0)

diff -up dhcp-3.1.0/common/bpf.c.xen dhcp-3.1.0/common/bpf.c

--- dhcp-3.1.0/common/bpf.c.xen	2007-05-23 19:30:32.000000000 -0400

+++ dhcp-3.1.0/common/bpf.c	2007-10-22 16:13:14.000000000 -0400

@@ -478,7 +478,7 @@ ssize_t receive_packet (interface, buf, 

 		offset = decode_udp_ip_header (interface,

 					       interface -> rbuf,

 					       interface -> rbuf_offset,

-  					       from, hdr.bh_caplen, &paylen);

+  					       from, hdr.bh_caplen, &paylen, 0);

 		/* If the IP or UDP checksum was bad, skip the packet... */

 		if (offset < 0) {

diff -up dhcp-3.1.0/common/packet.c.xen dhcp-3.1.0/common/packet.c

--- dhcp-3.1.0/common/packet.c.xen	2007-10-22 16:11:12.000000000 -0400

+++ dhcp-3.1.0/common/packet.c	2007-10-22 16:12:41.000000000 -0400

@@ -215,7 +215,7 @@ ssize_t

 decode_udp_ip_header(struct interface_info *interface,

 		     unsigned char *buf, unsigned bufix,

 		     struct sockaddr_in *from, unsigned buflen,

-		     unsigned *rbuflen)

+		     unsigned *rbuflen, int nocsum)

 {

   unsigned char *data;

   struct ip ip;

@@ -326,7 +326,7 @@ decode_udp_ip_header(struct interface_in

 					   8, IPPROTO_UDP + ulen))));

   udp_packets_seen++;

-  if (usum && usum != sum) {

+  if (!nocsum && usum && usum != sum) {

 	  udp_packets_bad_checksum++;

 	  if (udp_packets_seen > 4 &&

 	      (udp_packets_seen / udp_packets_bad_checksum) < 2) {

diff -up dhcp-3.1.0/includes/dhcpd.h.xen dhcp-3.1.0/includes/dhcpd.h

--- dhcp-3.1.0/includes/dhcpd.h.xen	2007-10-22 16:11:12.000000000 -0400

+++ dhcp-3.1.0/includes/dhcpd.h	2007-10-22 16:13:01.000000000 -0400

@@ -2140,7 +2140,7 @@ ssize_t decode_hw_header PROTO ((struct 

 				 unsigned, struct hardware *));

 ssize_t decode_udp_ip_header PROTO ((struct interface_info *, unsigned char *,

 				     unsigned, struct sockaddr_in *,

-				     unsigned, unsigned *));

+				     unsigned, unsigned *, int));

 /* ethernet.c */

 void assemble_ethernet_header PROTO ((struct interface_info *, unsigned char *,