fishHEADmaster

1 files changed, 99 insertions, 0 deletions

diff --git a/package/busybox/patches/241-udhcpc-oversized_packets.patch b/package/busybox/patches/241-udhcpc-oversized_packets.patch
new file mode 100644
index 0000000..471d704
--- /dev/null
+++ b/package/busybox/patches/241-udhcpc-oversized_packets.patch
@@ -0,0 +1,99 @@
+--- a/networking/udhcp/packet.c
++++ b/networking/udhcp/packet.c
+@@ -158,6 +158,11 @@ uint16_t FAST_FUNC udhcp_checksum(void *
+ 	return ~sum;
+ }
+ 
++int udhcp_get_payload_len(struct dhcp_packet *dhcp_pkt)
++{
++	return sizeof(struct dhcp_packet) - DHCP_OPTIONS_BUFSIZE + udhcp_end_option(dhcp_pkt->options) + sizeof(dhcp_pkt->options[0]);
++}
++
+ /* Construct a ip/udp header for a packet, send packet */
+ int FAST_FUNC udhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt,
+ 		uint32_t source_nip, int source_port,
+@@ -166,10 +171,10 @@ int FAST_FUNC udhcp_send_raw_packet(stru
+ {
+ 	struct sockaddr_ll dest_sll;
+ 	struct ip_udp_dhcp_packet packet;
+-	unsigned padding;
+ 	int fd;
+ 	int result = -1;
+ 	const char *msg;
++	int p_len = udhcp_get_payload_len(dhcp_pkt);
+ 
+ 	fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
+ 	if (fd < 0) {
+@@ -178,8 +183,8 @@ int FAST_FUNC udhcp_send_raw_packet(stru
+ 	}
+ 
+ 	memset(&dest_sll, 0, sizeof(dest_sll));
+-	memset(&packet, 0, offsetof(struct ip_udp_dhcp_packet, data));
+-	packet.data = *dhcp_pkt; /* struct copy */
++	memset(&packet, 0, sizeof(packet));
++	memcpy(&(packet.data), dhcp_pkt, p_len);
+ 
+ 	dest_sll.sll_family = AF_PACKET;
+ 	dest_sll.sll_protocol = htons(ETH_P_IP);
+@@ -192,36 +197,24 @@ int FAST_FUNC udhcp_send_raw_packet(stru
+ 		goto ret_close;
+ 	}
+ 
+-	/* We were sending full-sized DHCP packets (zero padded),
+-	 * but some badly configured servers were seen dropping them.
+-	 * Apparently they drop all DHCP packets >576 *ethernet* octets big,
+-	 * whereas they may only drop packets >576 *IP* octets big
+-	 * (which for typical Ethernet II means 590 octets: 6+6+2 + 576).
+-	 *
+-	 * In order to work with those buggy servers,
+-	 * we truncate packets after end option byte.
+-	 */
+-	padding = DHCP_OPTIONS_BUFSIZE - 1 - udhcp_end_option(packet.data.options);
+-
+ 	packet.ip.protocol = IPPROTO_UDP;
+ 	packet.ip.saddr = source_nip;
+ 	packet.ip.daddr = dest_nip;
+ 	packet.udp.source = htons(source_port);
+ 	packet.udp.dest = htons(dest_port);
+-	/* size, excluding IP header: */
+-	packet.udp.len = htons(UDP_DHCP_SIZE - padding);
+-	/* for UDP checksumming, ip.len is set to UDP packet len */
++	p_len += sizeof(packet.udp);
++	packet.udp.len = htons(p_len);
+ 	packet.ip.tot_len = packet.udp.len;
+-	packet.udp.check = udhcp_checksum(&packet, IP_UDP_DHCP_SIZE - padding);
+-	/* but for sending, it is set to IP packet len */
+-	packet.ip.tot_len = htons(IP_UDP_DHCP_SIZE - padding);
++	p_len += sizeof(packet.ip);
++	packet.udp.check = udhcp_checksum(&packet, p_len);
++	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));
+ 
+ 	udhcp_dump_packet(dhcp_pkt);
+-	result = sendto(fd, &packet, IP_UDP_DHCP_SIZE - padding, /*flags:*/ 0,
++	result = sendto(fd, &packet, p_len, /*flags:*/ 0,
+ 			(struct sockaddr *) &dest_sll, sizeof(dest_sll));
+ 	msg = "sendto";
+  ret_close:
+@@ -239,7 +232,6 @@ int FAST_FUNC udhcp_send_kernel_packet(s
+ 		uint32_t dest_nip, int dest_port)
+ {
+ 	struct sockaddr_in client;
+-	unsigned padding;
+ 	int fd;
+ 	int result = -1;
+ 	const char *msg;
+@@ -270,9 +262,7 @@ int FAST_FUNC udhcp_send_kernel_packet(s
+ 	}
+ 
+ 	udhcp_dump_packet(dhcp_pkt);
+-
+-	padding = DHCP_OPTIONS_BUFSIZE - 1 - udhcp_end_option(dhcp_pkt->options);
+-	result = safe_write(fd, dhcp_pkt, DHCP_SIZE - padding);
++	result = safe_write(fd, dhcp_pkt, udhcp_get_payload_len(dhcp_pkt));
+ 	msg = "write";
+  ret_close:
+ 	close(fd);