Remove unused (a.k.a. always passed NULL) parameter 'data' from

decode_udp_ip_header() and the useless check of it. Part of original
diff from pelikan about udp length errors.

3 files changed, 25 insertions, 26 deletions

diff --git a/usr.sbin/dhcpd/bpf.c b/usr.sbin/dhcpd/bpf.c
index efa3fcff140..a17147d03e3 100644
--- a/usr.sbin/dhcpd/bpf.c
+++ b/usr.sbin/dhcpd/bpf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bpf.c,v 1.8 2009/12/14 22:12:14 mpf Exp $	*/
+/*	$OpenBSD: bpf.c,v 1.9 2013/02/03 21:04:19 krw Exp $	*/
 
 /* BPF socket interface code, originally contributed by Archie Cobbs. */
 
@@ -341,7 +341,7 @@ receive_packet(struct interface_info *interface, unsigned char *buf,
 
 		/* Decode the IP and UDP headers... */
 		offset = decode_udp_ip_header(interface, interface->rbuf,
-		    interface->rbuf_offset, from, NULL, hdr.bh_caplen);
+		    interface->rbuf_offset, from, hdr.bh_caplen);
 
 		/* If the IP or UDP checksum was bad, skip the packet... */
 		if (offset < 0) {
diff --git a/usr.sbin/dhcpd/dhcpd.h b/usr.sbin/dhcpd/dhcpd.h
index 075d8222ad0..125e71fbfb2 100644
--- a/usr.sbin/dhcpd/dhcpd.h
+++ b/usr.sbin/dhcpd/dhcpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhcpd.h,v 1.45 2010/04/19 12:22:09 claudio Exp $ */
+/*	$OpenBSD: dhcpd.h,v 1.46 2013/02/03 21:04:19 krw Exp $ */
 
 /*
  * Copyright (c) 1995, 1996, 1997, 1998, 1999
@@ -679,7 +679,7 @@ void assemble_udp_ip_header(struct interface_info *, unsigned char *,
 ssize_t decode_hw_header(struct interface_info *, unsigned char *,
     int, struct hardware *);
 ssize_t decode_udp_ip_header(struct interface_info *, unsigned char *,
-    int, struct sockaddr_in *, unsigned char *, int);
+    int, struct sockaddr_in *, int);
 u_int32_t	checksum(unsigned char *, unsigned, u_int32_t);
 u_int32_t	wrapsum(u_int32_t);
 
diff --git a/usr.sbin/dhcpd/packet.c b/usr.sbin/dhcpd/packet.c
index 00e06d7dd97..30d221605a7 100644
--- a/usr.sbin/dhcpd/packet.c
+++ b/usr.sbin/dhcpd/packet.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: packet.c,v 1.4 2013/01/05 12:34:53 krw Exp $	*/
+/*	$OpenBSD: packet.c,v 1.5 2013/02/03 21:04:19 krw Exp $	*/
 
 /* Packet assembly code, originally contributed by Archie Cobbs. */
 
@@ -160,10 +160,11 @@ decode_hw_header(struct interface_info *interface, unsigned char *buf,
 
 ssize_t
 decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
-    int bufix, struct sockaddr_in *from, unsigned char *data, int buflen)
+    int bufix, struct sockaddr_in *from, int buflen)
 {
 	struct ip *ip;
 	struct udphdr *udp;
+	unsigned char *data;
 	u_int32_t ip_len = (buf[bufix] & 0xf) << 2;
 	u_int32_t sum, usum;
 	static int ip_packets_seen;
@@ -172,7 +173,7 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
 	static int udp_packets_bad_checksum;
 	static int udp_packets_length_checked;
 	static int udp_packets_length_overflow;
-	int len = 0;
+	int len;
 
 	ip = (struct ip *)(buf + bufix);
 	udp = (struct udphdr *)(buf + bufix + ip_len);
@@ -198,29 +199,27 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
 
 	/*
 	 * Compute UDP checksums, including the ``pseudo-header'', the
-	 * UDP header and the data.   If the UDP checksum field is zero,
+	 * UDP header and the data. If the UDP checksum field is zero,
 	 * we're not supposed to do a checksum.
 	 */
-	if (!data) {
-		data = buf + bufix + ip_len + sizeof(*udp);
-		len = ntohs(udp->uh_ulen) - sizeof(*udp);
-		udp_packets_length_checked++;
-		if ((len < 0) || (len + data > buf + bufix + buflen)) {
-			udp_packets_length_overflow++;
-			if (udp_packets_length_checked > 4 &&
-			    (udp_packets_length_checked /
-			    udp_packets_length_overflow) < 2) {
-				note("%d udp packets in %d too long - dropped",
-				    udp_packets_length_overflow,
-				    udp_packets_length_checked);
-				udp_packets_length_overflow =
-				    udp_packets_length_checked = 0;
-			}
-			return (-1);
+	data = buf + bufix + ip_len + sizeof(*udp);
+	len = ntohs(udp->uh_ulen) - sizeof(*udp);
+	udp_packets_length_checked++;
+	if ((len < 0) || (len + data > buf + bufix + buflen)) {
+		udp_packets_length_overflow++;
+		if (udp_packets_length_checked > 4 &&
+		    (udp_packets_length_checked /
+		    udp_packets_length_overflow) < 2) {
+			note("%d udp packets in %d too long - dropped",
+			    udp_packets_length_overflow,
+			    udp_packets_length_checked);
+			udp_packets_length_overflow =
+			    udp_packets_length_checked = 0;
 		}
-		if (len + data != buf + bufix + buflen)
-			debug("accepting packet with data after udp payload.");
+		return (-1);
 	}
+	if (len + data != buf + bufix + buflen)
+		debug("accepting packet with data after udp payload.");
 
 	usum = udp->uh_sum;
 	udp->uh_sum = 0;