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| author | Baruch Siach | 2011-09-07 17:52:37 +0200 |
|---|---|---|
| committer | Denys Vlasenko | 2011-09-07 17:55:40 +0200 |
| commit | e8f36330d9bb27f9f7e66aa6f01ff92c07d86f62 (patch) | |
| tree | 863018163a166cc690902d8027a3f04f9f812dd3 /networking/udhcp | |
| parent | 8c84f7545cf08925edb23d94d9f6519b338267c6 (diff) | |
| download | busybox-e8f36330d9bb27f9f7e66aa6f01ff92c07d86f62.zip busybox-e8f36330d9bb27f9f7e66aa6f01ff92c07d86f62.tar.gz | |
networking: consolidate the IP checksum code. -129 bytes.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'networking/udhcp')
| -rw-r--r-- | networking/udhcp/dhcpc.c | 4 | ||||
| -rw-r--r-- | networking/udhcp/packet.c | 34 |
2 files changed, 5 insertions, 33 deletions
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c index 4d755e6..3be09f4 100644 --- a/networking/udhcp/dhcpc.c +++ b/networking/udhcp/dhcpc.c @@ -739,7 +739,7 @@ static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd) /* verify IP checksum */ check = packet.ip.check; packet.ip.check = 0; - if (check != udhcp_checksum(&packet.ip, sizeof(packet.ip))) { + if (check != inet_cksum((uint16_t *)&packet.ip, sizeof(packet.ip))) { log1("Bad IP header checksum, ignoring"); return -2; } @@ -750,7 +750,7 @@ static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd) packet.ip.tot_len = packet.udp.len; /* yes, this is needed */ check = packet.udp.check; packet.udp.check = 0; - if (check && check != udhcp_checksum(&packet, bytes)) { + if (check && check != inet_cksum((uint16_t *)&packet, bytes)) { log1("Packet with bad UDP checksum received, ignoring"); return -2; } diff --git a/networking/udhcp/packet.c b/networking/udhcp/packet.c index 66b42c5..4d5ff06 100644 --- a/networking/udhcp/packet.c +++ b/networking/udhcp/packet.c @@ -129,35 +129,6 @@ int FAST_FUNC udhcp_recv_kernel_packet(struct dhcp_packet *packet, int fd) return bytes; } -uint16_t FAST_FUNC udhcp_checksum(void *addr, int count) -{ - /* Compute Internet Checksum for "count" bytes - * beginning at location "addr". - */ - int32_t sum = 0; - uint16_t *source = (uint16_t *) addr; - - while (count > 1) { - /* This is the inner loop */ - sum += *source++; - count -= 2; - } - - /* Add left-over byte, if any */ - if (count > 0) { - /* Make sure that the left-over byte is added correctly both - * with little and big endian hosts */ - uint16_t tmp = 0; - *(uint8_t*)&tmp = *(uint8_t*)source; - sum += tmp; - } - /* Fold 32-bit sum to 16 bits */ - while (sum >> 16) - sum = (sum & 0xffff) + (sum >> 16); - - return ~sum; -} - /* 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, @@ -212,13 +183,14 @@ int FAST_FUNC udhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt, packet.udp.len = htons(UDP_DHCP_SIZE - padding); /* for UDP checksumming, ip.len is set to UDP packet len */ packet.ip.tot_len = packet.udp.len; - packet.udp.check = udhcp_checksum(&packet, IP_UDP_DHCP_SIZE - padding); + packet.udp.check = inet_cksum((uint16_t *)&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); 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)); + packet.ip.check = inet_cksum((uint16_t *)&packet.ip, sizeof(packet.ip)); udhcp_dump_packet(dhcp_pkt); result = sendto(fd, &packet, IP_UDP_DHCP_SIZE - padding, /*flags:*/ 0, |