From: Denis Vlasenko <vda.linux@googlemail.com>
Date: Mon, 20 Nov 2006 01:13:09 +0000 (-0000)
Subject: add compile-time check for correct DHCP packet size
X-Git-Tag: 1_4_0~382
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=c9cdeaa3fef3f93eb259957d36c760ec8902e0c1;p=oweals%2Fbusybox.git

add compile-time check for correct DHCP packet size
---

diff --git a/networking/udhcp/packet.c b/networking/udhcp/packet.c
index e79542d08..85910447b 100644
--- a/networking/udhcp/packet.c
+++ b/networking/udhcp/packet.c
@@ -109,6 +109,7 @@ uint16_t udhcp_checksum(void *addr, int count)
 
 
 /* Construct a ip/udp header for a packet, and specify the source and dest hardware address */
+void BUG_sizeof_struct_udp_dhcp_packet_must_be_576(void);
 int udhcp_raw_packet(struct dhcpMessage *payload,
 		uint32_t source_ip, int source_port,
 		uint32_t dest_ip, int dest_port, uint8_t *dest_arp, int ifindex)
@@ -154,6 +155,9 @@ int udhcp_raw_packet(struct dhcpMessage *payload,
 	packet.ip.ttl = IPDEFTTL;
 	packet.ip.check = udhcp_checksum(&(packet.ip), sizeof(packet.ip));
 
+	if (sizeof(struct udp_dhcp_packet) != 576)
+		BUG_sizeof_struct_udp_dhcp_packet_must_be_576();
+
 	result = sendto(fd, &packet, sizeof(struct udp_dhcp_packet), 0,
 			(struct sockaddr *) &dest, sizeof(dest));
 	if (result <= 0) {