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diff -ruN busybox-1.2.1-old/networking/udhcp/packet.c busybox-1.2.1-new/networking/udhcp/packet.c
--- busybox-1.2.1-old/networking/udhcp/packet.c 2006-07-01 00:42:02.000000000 +0200
+++ busybox-1.2.1-new/networking/udhcp/packet.c 2006-11-19 01:04:40.000000000 +0100
@@ -111,6 +111,10 @@
return ~sum;
}
+int udhcp_get_payload_len(struct dhcpMessage *payload)
+{
+ return sizeof(struct dhcpMessage) - MAX_OPTIONS_LEN + end_option(payload->options) + sizeof(payload->options[0]);
+}
/* Construct a ip/udp header for a packet, and specify the source and dest hardware address */
int udhcp_raw_packet(struct dhcpMessage *payload, uint32_t source_ip, int source_port,
@@ -120,6 +124,7 @@
int result;
struct sockaddr_ll dest;
struct udp_dhcp_packet packet;
+ int p_len = udhcp_get_payload_len(payload);
if ((fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP))) < 0) {
DEBUG(LOG_ERR, "socket call failed: %m");
@@ -128,6 +133,7 @@
memset(&dest, 0, sizeof(dest));
memset(&packet, 0, sizeof(packet));
+ memcpy(&(packet.data), payload, p_len);
dest.sll_family = AF_PACKET;
dest.sll_protocol = htons(ETH_P_IP);
@@ -145,18 +151,19 @@
packet.ip.daddr = dest_ip;
packet.udp.source = htons(source_port);
packet.udp.dest = htons(dest_port);
- packet.udp.len = htons(sizeof(packet.udp) + sizeof(struct dhcpMessage)); /* cheat on the psuedo-header */
+ p_len += sizeof(packet.udp);
+ packet.udp.len = htons(p_len);
packet.ip.tot_len = packet.udp.len;
- memcpy(&(packet.data), payload, sizeof(struct dhcpMessage));
- packet.udp.check = udhcp_checksum(&packet, sizeof(struct udp_dhcp_packet));
+ p_len += sizeof(packet.ip);
+ packet.udp.check = udhcp_checksum(&packet, p_len);
- packet.ip.tot_len = htons(sizeof(struct udp_dhcp_packet));
+ packet.ip.tot_len = htons(p_len);
packet.ip.ihl = sizeof(packet.ip) >> 2;
packet.ip.version = IPVERSION;
packet.ip.ttl = IPDEFTTL;
packet.ip.check = udhcp_checksum(&(packet.ip), sizeof(packet.ip));
- result = sendto(fd, &packet, sizeof(struct udp_dhcp_packet), 0, (struct sockaddr *) &dest, sizeof(dest));
+ result = sendto(fd, &packet, p_len, 0, (struct sockaddr *) &dest, sizeof(dest));
if (result <= 0) {
DEBUG(LOG_ERR, "write on socket failed: %m");
}
@@ -201,7 +208,7 @@
return -1;
}
- result = write(fd, payload, sizeof(struct dhcpMessage));
+ result = write(fd, payload, udhcp_get_payload_len(payload));
close(fd);
return result;
}
diff -ruN busybox-1.2.1-old/networking/udhcp/packet.h busybox-1.2.1-new/networking/udhcp/packet.h
--- busybox-1.2.1-old/networking/udhcp/packet.h 2006-07-01 00:42:02.000000000 +0200
+++ busybox-1.2.1-new/networking/udhcp/packet.h 2006-11-19 00:49:38.000000000 +0100
@@ -4,6 +4,8 @@
#include <netinet/udp.h>
#include <netinet/ip.h>
+#define MAX_OPTIONS_LEN 308
+
struct dhcpMessage {
uint8_t op;
uint8_t htype;
@@ -20,7 +22,7 @@
uint8_t sname[64];
uint8_t file[128];
uint32_t cookie;
- uint8_t options[308]; /* 312 - cookie */
+ uint8_t options[MAX_OPTIONS_LEN]; /* 312 - cookie */
};
struct udp_dhcp_packet {
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