X-Git-Url: https://git.rohieb.name/openwrt.git/blobdiff_plain/9dfc3e34ee54d00b68cc4cbb5cddcfa588fd07fb..de50d6624ffd8250930462e43163bdec1747a999:/package/busybox/patches/241-udhcpc-oversized_packets.patch

diff --git a/package/busybox/patches/241-udhcpc-oversized_packets.patch b/package/busybox/patches/241-udhcpc-oversized_packets.patch
index 405a7a52e..471d704a7 100644
--- a/package/busybox/patches/241-udhcpc-oversized_packets.patch
+++ b/package/busybox/patches/241-udhcpc-oversized_packets.patch
@@ -1,51 +1,69 @@
 --- a/networking/udhcp/packet.c
 +++ b/networking/udhcp/packet.c
-@@ -120,6 +120,10 @@ uint16_t FAST_FUNC udhcp_checksum(void *
+@@ -158,6 +158,11 @@ uint16_t FAST_FUNC udhcp_checksum(void *
  	return ~sum;
  }
  
-+int udhcp_get_payload_len(struct dhcpMessage *payload)
++int udhcp_get_payload_len(struct dhcp_packet *dhcp_pkt)
 +{
-+	return sizeof(struct dhcpMessage) - DHCP_OPTIONS_BUFSIZE + end_option(payload->options) + sizeof(payload->options[0]);
++	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 dhcpMessage *payload,
-@@ -132,11 +136,7 @@ int FAST_FUNC udhcp_send_raw_packet(stru
+ 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;
--
--	enum {
--		IP_UPD_DHCP_SIZE = sizeof(struct udp_dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS,
--		UPD_DHCP_SIZE    = IP_UPD_DHCP_SIZE - offsetof(struct udp_dhcp_packet, udp),
--	};
-+	int p_len = udhcp_get_payload_len(payload);
++	int p_len = udhcp_get_payload_len(dhcp_pkt);
  
  	fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
  	if (fd < 0) {
-@@ -146,7 +146,7 @@ int FAST_FUNC udhcp_send_raw_packet(stru
+@@ -178,8 +183,8 @@ int FAST_FUNC udhcp_send_raw_packet(stru
+ 	}
  
- 	memset(&dest, 0, sizeof(dest));
- 	memset(&packet, 0, sizeof(packet));
--	packet.data = *payload; /* struct copy */
-+	memcpy(&(packet.data), payload, p_len);
+ 	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_family = AF_PACKET;
- 	dest.sll_protocol = htons(ETH_P_IP);
-@@ -163,23 +163,18 @@ int FAST_FUNC udhcp_send_raw_packet(stru
- 	packet.ip.daddr = dest_ip;
+ 	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(UPD_DHCP_SIZE);
+-	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_UPD_DHCP_SIZE);
+-	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_UPD_DHCP_SIZE);
+-	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);
@@ -54,22 +72,28 @@
  	packet.ip.ttl = IPDEFTTL;
  	packet.ip.check = udhcp_checksum(&packet.ip, sizeof(packet.ip));
  
--	/* Currently we send full-sized DHCP packets (zero padded).
--	 * If you need to change this: last byte of the packet is
--	 * packet.data.options[end_option(packet.data.options)]
--	 */
--	result = sendto(fd, &packet, IP_UPD_DHCP_SIZE, 0,
-+	result = sendto(fd, &packet, p_len, 0,
- 				(struct sockaddr *) &dest, sizeof(dest));
+ 	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:
-@@ -231,8 +226,7 @@ int FAST_FUNC udhcp_send_kernel_packet(s
- 		goto 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
  	}
  
--	/* Currently we send full-sized DHCP packets (see above) */
--	result = safe_write(fd, payload, DHCP_SIZE);
-+	result = safe_write(fd, payload, udhcp_get_payload_len(payload));
+ 	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);