diff --git a/src/include/gpxe/icmp6.h b/src/include/gpxe/icmp6.h
index 76aaddfe..34093616 100644
--- a/src/include/gpxe/icmp6.h
+++ b/src/include/gpxe/icmp6.h
@@ -7,7 +7,6 @@
  *
  */
 
-#include <ip.h>
 #include <gpxe/ip6.h>
 #include <gpxe/ndp.h>
 
diff --git a/src/include/gpxe/ip.h b/src/include/gpxe/ip.h
index 0a23565b..b1b0c48c 100644
--- a/src/include/gpxe/ip.h
+++ b/src/include/gpxe/ip.h
@@ -7,9 +7,15 @@
  *
  */
 
-#include <ip.h>
+#include <stdint.h>
+#include <gpxe/in.h>
+#include <gpxe/list.h>
 #include <gpxe/retry.h>
 
+struct io_buffer;
+struct net_device;
+struct net_protocol;
+
 /* IP constants */
 
 #define IP_VER			0x40U
@@ -27,7 +33,21 @@
 #define IP_FRAG_IOB_SIZE	1500
 #define IP_FRAG_TIMEOUT		50
 
-/* IP4 pseudo header */
+/** An IPv4 packet header */
+struct iphdr {
+	uint8_t  verhdrlen;
+	uint8_t  service;
+	uint16_t len;
+	uint16_t ident;
+	uint16_t frags;
+	uint8_t  ttl;
+	uint8_t  protocol;
+	uint16_t chksum;
+	struct in_addr src;
+	struct in_addr dest;
+} __attribute__ (( packed ));
+
+/** An IPv4 pseudo header */
 struct ipv4_pseudo_header {
 	struct in_addr src;
 	struct in_addr dest;
@@ -68,11 +88,6 @@ struct frag_buffer {
 	struct list_head list;
 };
 
-struct io_buffer;
-struct net_device;
-struct net_protocol;
-struct tcpip_protocol;
-
 extern struct list_head ipv4_miniroutes;
 
 extern struct net_protocol ipv4_protocol;
diff --git a/src/include/gpxe/ip6.h b/src/include/gpxe/ip6.h
index 22989ec9..dc0ae31f 100644
--- a/src/include/gpxe/ip6.h
+++ b/src/include/gpxe/ip6.h
@@ -7,7 +7,7 @@
  *
  */
 
-#include <ip.h>
+#include <stdint.h>
 #include <gpxe/in.h>
 
 /* IP6 constants */
diff --git a/src/include/ip.h b/src/include/ip.h
deleted file mode 100644
index 9da7f56a..00000000
--- a/src/include/ip.h
+++ /dev/null
@@ -1,23 +0,0 @@
-#ifndef	_IP_H
-#define	_IP_H
-
-#include "stddef.h"
-#include "stdint.h"
-#include <gpxe/in.h>
-
-struct iphdr {
-	uint8_t  verhdrlen;
-	uint8_t  service;
-	uint16_t len;
-	uint16_t ident;
-	uint16_t frags;
-	uint8_t  ttl;
-	uint8_t  protocol;
-	uint16_t chksum;
-	struct in_addr src;
-	struct in_addr dest;
-} PACKED;
-
-extern uint16_t tcpudpchksum(struct iphdr *ip);
-
-#endif	/* _IP_H */
diff --git a/src/include/udp.h b/src/include/udp.h
deleted file mode 100644
index 7814c5f4..00000000
--- a/src/include/udp.h
+++ /dev/null
@@ -1,29 +0,0 @@
-#ifndef	_UDP_H
-#define	_UDP_H
-
-#include "stddef.h"
-#include "stdint.h"
-#include <gpxe/in.h>
-#include "ip.h"
-
-struct udp_pseudo_hdr {
-	struct in_addr  src;
-	struct in_addr  dest;
-	uint8_t  unused;
-	uint8_t  protocol;
-	uint16_t len;
-} PACKED;
-struct udphdr {
-	uint16_t src;
-	uint16_t dest;
-	uint16_t len;
-	uint16_t chksum;
-	struct {} payload;
-} PACKED;
-struct udppacket {
-	struct iphdr	ip;
-	struct udphdr	udp;
-	struct {} payload;
-} PACKED;
-
-#endif	/* _UDP_H */
diff --git a/src/proto/igmp.c b/src/proto/igmp.c
index ef1ff714..d711421a 100644
--- a/src/proto/igmp.c
+++ b/src/proto/igmp.c
@@ -3,11 +3,11 @@
  *
  */
 
+#if 0
+
 #include <ip.h>
 #include <igmp.h>
 
-#if 0
-
 static unsigned long last_igmpv1 = 0;
 static struct igmptable_t igmptable[MAX_IGMP];