| 1 | --- a/networking/udhcp/packet.c |
| 2 | +++ b/networking/udhcp/packet.c |
| 3 | @@ -164,6 +164,11 @@ uint16_t FAST_FUNC udhcp_checksum(void * |
| 4 | return ~sum; |
| 5 | } |
| 6 | |
| 7 | +int udhcp_get_payload_len(struct dhcp_packet *dhcp_pkt) |
| 8 | +{ |
| 9 | + return sizeof(struct dhcp_packet) - DHCP_OPTIONS_BUFSIZE + end_option(dhcp_pkt->options) + sizeof(dhcp_pkt->options[0]); |
| 10 | +} |
| 11 | + |
| 12 | /* Construct a ip/udp header for a packet, send packet */ |
| 13 | int FAST_FUNC udhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt, |
| 14 | uint32_t source_ip, int source_port, |
| 15 | @@ -175,11 +180,7 @@ int FAST_FUNC udhcp_send_raw_packet(stru |
| 16 | int fd; |
| 17 | int result = -1; |
| 18 | const char *msg; |
| 19 | - |
| 20 | - enum { |
| 21 | - IP_UPD_DHCP_SIZE = sizeof(struct ip_udp_dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS, |
| 22 | - UPD_DHCP_SIZE = IP_UPD_DHCP_SIZE - offsetof(struct ip_udp_dhcp_packet, udp), |
| 23 | - }; |
| 24 | + int p_len = udhcp_get_payload_len(dhcp_pkt); |
| 25 | |
| 26 | fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP)); |
| 27 | if (fd < 0) { |
| 28 | @@ -189,7 +190,7 @@ int FAST_FUNC udhcp_send_raw_packet(stru |
| 29 | |
| 30 | memset(&dest, 0, sizeof(dest)); |
| 31 | memset(&packet, 0, sizeof(packet)); |
| 32 | - packet.data = *dhcp_pkt; /* struct copy */ |
| 33 | + memcpy(&(packet.data), dhcp_pkt, p_len); |
| 34 | |
| 35 | dest.sll_family = AF_PACKET; |
| 36 | dest.sll_protocol = htons(ETH_P_IP); |
| 37 | @@ -206,24 +207,19 @@ int FAST_FUNC udhcp_send_raw_packet(stru |
| 38 | packet.ip.daddr = dest_ip; |
| 39 | packet.udp.source = htons(source_port); |
| 40 | packet.udp.dest = htons(dest_port); |
| 41 | - /* size, excluding IP header: */ |
| 42 | - packet.udp.len = htons(UPD_DHCP_SIZE); |
| 43 | - /* for UDP checksumming, ip.len is set to UDP packet len */ |
| 44 | + p_len += sizeof(packet.udp); |
| 45 | + packet.udp.len = htons(p_len); |
| 46 | packet.ip.tot_len = packet.udp.len; |
| 47 | - packet.udp.check = udhcp_checksum(&packet, IP_UPD_DHCP_SIZE); |
| 48 | - /* but for sending, it is set to IP packet len */ |
| 49 | - packet.ip.tot_len = htons(IP_UPD_DHCP_SIZE); |
| 50 | + p_len += sizeof(packet.ip); |
| 51 | + packet.udp.check = udhcp_checksum(&packet, p_len); |
| 52 | + packet.ip.tot_len = htons(p_len); |
| 53 | packet.ip.ihl = sizeof(packet.ip) >> 2; |
| 54 | packet.ip.version = IPVERSION; |
| 55 | packet.ip.ttl = IPDEFTTL; |
| 56 | packet.ip.check = udhcp_checksum(&packet.ip, sizeof(packet.ip)); |
| 57 | |
| 58 | - /* Currently we send full-sized DHCP packets (zero padded). |
| 59 | - * If you need to change this: last byte of the packet is |
| 60 | - * packet.data.options[end_option(packet.data.options)] |
| 61 | - */ |
| 62 | udhcp_dump_packet(dhcp_pkt); |
| 63 | - result = sendto(fd, &packet, IP_UPD_DHCP_SIZE, 0, |
| 64 | + result = sendto(fd, &packet, p_len, 0, |
| 65 | (struct sockaddr *) &dest, sizeof(dest)); |
| 66 | msg = "sendto"; |
| 67 | ret_close: |
| 68 | @@ -245,10 +241,6 @@ int FAST_FUNC udhcp_send_kernel_packet(s |
| 69 | int result = -1; |
| 70 | const char *msg; |
| 71 | |
| 72 | - enum { |
| 73 | - DHCP_SIZE = sizeof(struct dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS, |
| 74 | - }; |
| 75 | - |
| 76 | fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP); |
| 77 | if (fd < 0) { |
| 78 | msg = "socket(%s)"; |
| 79 | @@ -274,9 +266,8 @@ int FAST_FUNC udhcp_send_kernel_packet(s |
| 80 | goto ret_close; |
| 81 | } |
| 82 | |
| 83 | - /* Currently we send full-sized DHCP packets (see above) */ |
| 84 | udhcp_dump_packet(dhcp_pkt); |
| 85 | - result = safe_write(fd, dhcp_pkt, DHCP_SIZE); |
| 86 | + result = safe_write(fd, dhcp_pkt, udhcp_get_payload_len(dhcp_pkt)); |
| 87 | msg = "write"; |
| 88 | ret_close: |
| 89 | close(fd); |
| 90 | |
