dark/zerotiertspu
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ARP packets do need the source IP address in them, as well as the MAC address.

Browse source 
Packets wouldn't even show up in WireShark without the source IP in it.
This commit is contained in:
Grant Limberg 2015-11-21 19:14:59 -08:00
parent ac09c3569a
commit 764dd1c3d9
2 changed files with 9 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

11
osdep/Arp.cpp
View file

@ -104,11 +104,11 @@ uint32_t Arp::processIncomingArp(const void *arp,unsigned int len,void *response
return ip;
}
MAC Arp::query(const MAC &localMac,uint32_t ip,void *query,unsigned int &queryLen,MAC &queryDest)
MAC Arp::query(const MAC &localMac,uint32_t localIp,uint32_t targetIp,void *query,unsigned int &queryLen,MAC &queryDest)
{
const uint64_t now = OSUtils::now();
_ArpEntry &e = _cache[ip];
_ArpEntry &e = _cache[targetIp];
if ( ((e.mac)&&((now - e.lastResponseReceived) >= (ZT_ARP_EXPIRE / 3))) ||
((!e.mac)&&((now - e.lastQuerySent) >= ZT_ARP_QUERY_INTERVAL)) ) {
@ -116,9 +116,10 @@ MAC Arp::query(const MAC &localMac,uint32_t ip,void *query,unsigned int &queryLe
uint8_t *q = reinterpret_cast<uint8_t *>(query);
memcpy(q,ARP_REQUEST_HEADER,8); q += 8; // ARP request header information, always the same
localMac.copyTo(q,6); q += 6; // sending host address
memset(q,0,10); q += 10; // sending IP and target media address are ignored in requests
memcpy(q,&ip,4); // target IP address for resolution (IP already in big-endian byte order)
localMac.copyTo(q,6); q += 6; // sending host MAC address
memcpy(q,&localIp,4); q += 4; // sending host IP (IP already in big-endian byte order)
memset(q,0,6); q += 6; // sending zeros for target MAC address as thats what we want to find
memcpy(q,&targetIp,4); // target IP address for resolution (IP already in big-endian byte order)
queryLen = 28;
if (e.mac)
queryDest = e.mac; // confirmation query, send directly to address holder