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>
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 @@
/* 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 @@
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 @@
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 @@
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,