/* Found it */
uint16_t oldmss = DATA(packet)[start + 22 + i] << 8 | DATA(packet)[start + 23 + i];
uint16_t newmss = mtu - start - 20;
- uint16_t csum = DATA(packet)[start + 16] << 8 | DATA(packet)[start + 17];
+ uint32_t csum = DATA(packet)[start + 16] << 8 | DATA(packet)[start + 17];
if(oldmss <= newmss)
break;
DATA(packet)[start + 22 + i] = newmss >> 8;
DATA(packet)[start + 23 + i] = newmss & 0xff;
csum ^= 0xffff;
- csum -= oldmss;
+ csum += oldmss ^ 0xffff;
csum += newmss;
+ csum = (csum & 0xffff) + (csum >> 16);
+ csum += csum >> 16;
csum ^= 0xffff;
DATA(packet)[start + 16] = csum >> 8;
- DATA(packet)[start + 17] = csum & 0xff;
+ DATA(packet)[start + 17] = csum;
break;
}
}
if(subnet->owner == myself)
return; /* silently ignore */
- memcpy(DATA(packet), DATA(packet) + ETH_ALEN, ETH_ALEN); /* copy destination address */
- DATA(packet)[ETH_ALEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
-
memcpy(&addr, arp.arp_tpa, sizeof addr); /* save protocol addr */
memcpy(arp.arp_tpa, arp.arp_spa, sizeof addr); /* swap destination and source protocol address */
memcpy(arp.arp_spa, &addr, sizeof addr); /* ... */
memcpy(arp.arp_tha, arp.arp_sha, ETH_ALEN); /* set target hard/proto addr */
- memcpy(arp.arp_sha, DATA(packet) + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
+ memcpy(arp.arp_sha, DATA(packet) + ETH_ALEN, ETH_ALEN); /* set source hard/proto addr */
+ arp.arp_sha[ETH_ALEN - 1] ^= 0xFF; /* for consistency with route_packet() */
arp.arp_op = htons(ARPOP_REPLY);
/* Copy structs on stack back to packet */