int arpInform()
{
arpMessage ArpMsgSend;
struct sockaddr addr;
int len;
memset(&ArpMsgSend,0,sizeof(arpMessage));
memcpy(ArpMsgSend.ethhdr.ether_dhost,MAC_BCAST_ADDR,ETH_ALEN);
memcpy(ArpMsgSend.ethhdr.ether_shost,ClientHwAddr,ETH_ALEN);
ArpMsgSend.ethhdr.ether_type = htons(ETHERTYPE_ARP);
ArpMsgSend.htype = (TokenRingIf) ? htons(ARPHRD_IEEE802_TR) : htons(ARPHRD_ETHER);
ArpMsgSend.ptype = htons(ETHERTYPE_IP);
ArpMsgSend.hlen = ETH_ALEN;
ArpMsgSend.plen = 4;
ArpMsgSend.operation = htons(ARPOP_REPLY);
memcpy(ArpMsgSend.sHaddr,ClientHwAddr,ETH_ALEN);
memcpy(ArpMsgSend.tHaddr,DhcpIface.shaddr,ETH_ALEN);
memcpy(ArpMsgSend.sInaddr,&DhcpIface.ciaddr,4);
memcpy(ArpMsgSend.tInaddr,&inaddr_broadcast,4);
memset(&addr,0,sizeof(struct sockaddr));
memcpy(addr.sa_data,IfName,IfName_len);
if ( TokenRingIf )
len = eth2tr(&ArpMsgSend.ethhdr,BasicArpLen(ArpMsgSend));
else
len = sizeof(arpMessage);
if ( sendto(dhcpSocket,&ArpMsgSend,len,0,
&addr,sizeof(struct sockaddr)) == -1 )
{
syslog(LOG_ERR,"arpInform: sendto: %m\n");
return -1;
}
return 0;
}
int arpRelease() /* sends UNARP message, cf. RFC1868 */
{
arpMessage ArpMsgSend;
struct sockaddr addr;
int len;
/* build Ethernet header */
memset(&ArpMsgSend,0,sizeof(arpMessage));
memcpy(ArpMsgSend.ethhdr.ether_dhost,MAC_BCAST_ADDR,ETH_ALEN);
memcpy(ArpMsgSend.ethhdr.ether_shost,ClientHwAddr,ETH_ALEN);
ArpMsgSend.ethhdr.ether_type = htons(ETHERTYPE_ARP);
/* build UNARP message */
ArpMsgSend.htype = (TokenRingIf) ? htons(ARPHRD_IEEE802_TR) : htons(ARPHRD_ETHER);
ArpMsgSend.ptype = htons(ETHERTYPE_IP);
ArpMsgSend.plen = 4;
ArpMsgSend.operation = htons(ARPOP_REPLY);
memcpy(&ArpMsgSend.sInaddr,&DhcpIface.ciaddr,4);
memcpy(&ArpMsgSend.tInaddr,&inaddr_broadcast,4);
memset(&addr,0,sizeof(struct sockaddr));
memcpy(addr.sa_data,IfName,IfName_len);
if ( TokenRingIf )
len = eth2tr(&ArpMsgSend.ethhdr,BasicArpLen(ArpMsgSend));
else
len = sizeof(arpMessage);
if ( sendto(dhcpSocket,&ArpMsgSend,len,0,
&addr,sizeof(struct sockaddr)) == -1 )
{
syslog(LOG_ERR,"arpRelease: sendto: %s\n",strerror(errno));
return -1;
}
return 0;
}
int arpCheck()
{
arpMessage ArpMsgSend,ArpMsgRecv;
struct sockaddr addr;
int j,i=0,len=0;
memset(&ArpMsgSend,0,sizeof(arpMessage));
memcpy(ArpMsgSend.ethhdr.ether_dhost,MAC_BCAST_ADDR,ETH_ALEN);
memcpy(ArpMsgSend.ethhdr.ether_shost,ClientHwAddr,ETH_ALEN);
ArpMsgSend.ethhdr.ether_type = htons(ETHERTYPE_ARP);
ArpMsgSend.htype = (TokenRingIf) ? htons(ARPHRD_IEEE802_TR) : htons(ARPHRD_ETHER);
ArpMsgSend.ptype = htons(ETHERTYPE_IP);
ArpMsgSend.hlen = ETH_ALEN;
ArpMsgSend.plen = 4;
ArpMsgSend.operation = htons(ARPOP_REQUEST);
memcpy(ArpMsgSend.sHaddr,ClientHwAddr,ETH_ALEN);
memcpy(&ArpMsgSend.tInaddr,&DhcpIface.ciaddr,4);
if ( DebugFlag ) syslog(LOG_DEBUG,
"broadcasting ARPOP_REQUEST for %u.%u.%u.%u\n",
ArpMsgSend.tInaddr[0],ArpMsgSend.tInaddr[1],
ArpMsgSend.tInaddr[2],ArpMsgSend.tInaddr[3]);
do
{
do
{
if ( i++ > 4 ) return 0; /* 5 probes */
memset(&addr,0,sizeof(struct sockaddr));
memcpy(addr.sa_data,IfName,IfName_len);
if ( TokenRingIf )
len = eth2tr(&ArpMsgSend.ethhdr,BasicArpLen(ArpMsgSend));
else
len = sizeof(arpMessage);
if ( sendto(dhcpSocket,&ArpMsgSend,len,0,
&addr,sizeof(struct sockaddr)) == -1 )
{
syslog(LOG_ERR,"arpCheck: sendto: %m\n");
return -1;
}
}
while ( peekfd(dhcpSocket,50000) ); /* 50 msec timeout */
do
{
memset(&ArpMsgRecv,0,sizeof(arpMessage));
j=sizeof(struct sockaddr);
if ( recvfrom(dhcpSocket,&ArpMsgRecv,sizeof(arpMessage),0,
(struct sockaddr *)&addr,&j) == -1 )
{
syslog(LOG_ERR,"arpCheck: recvfrom: %m\n");
return -1;
}
if ( TokenRingIf )
{
if ( tr2eth(&ArpMsgRecv.ethhdr) ) continue;
}
if ( ArpMsgRecv.ethhdr.ether_type != htons(ETHERTYPE_ARP) )
continue;
if ( ArpMsgRecv.operation == htons(ARPOP_REPLY) )
{
if ( DebugFlag ) syslog(LOG_DEBUG,
"ARPOP_REPLY received from %u.%u.%u.%u for %u.%u.%u.%u\n",
ArpMsgRecv.sInaddr[0],ArpMsgRecv.sInaddr[1],
ArpMsgRecv.sInaddr[2],ArpMsgRecv.sInaddr[3],
ArpMsgRecv.tInaddr[0],ArpMsgRecv.tInaddr[1],
ArpMsgRecv.tInaddr[2],ArpMsgRecv.tInaddr[3]);
}
else
continue;
if ( memcmp(ArpMsgRecv.tHaddr,ClientHwAddr,ETH_ALEN) )
{
if ( DebugFlag )
syslog(LOG_DEBUG,
"target hardware address mismatch: %02X.%02X.%02X.%02X.%02X.%02X received, %02X.%02X.%02X.%02X.%02X.%02X expected\n",
ArpMsgRecv.tHaddr[0],ArpMsgRecv.tHaddr[1],ArpMsgRecv.tHaddr[2],
ArpMsgRecv.tHaddr[3],ArpMsgRecv.tHaddr[4],ArpMsgRecv.tHaddr[5],
ClientHwAddr[0],ClientHwAddr[1],
ClientHwAddr[2],ClientHwAddr[3],
ClientHwAddr[4],ClientHwAddr[5]);
continue;
}
if ( memcmp(&ArpMsgRecv.sInaddr,&DhcpIface.ciaddr,4) )
{
if ( DebugFlag )
syslog(LOG_DEBUG,
"sender IP address mismatch: %u.%u.%u.%u received, %u.%u.%u.%u expected\n",
ArpMsgRecv.sInaddr[0],ArpMsgRecv.sInaddr[1],ArpMsgRecv.sInaddr[2],ArpMsgRecv.sInaddr[3],
((unsigned char *)&DhcpIface.ciaddr)[0],
((unsigned char *)&DhcpIface.ciaddr)[1],
((unsigned char *)&DhcpIface.ciaddr)[2],
((unsigned char *)&DhcpIface.ciaddr)[3]);
continue;
}
return 1;
}
while ( peekfd(dhcpSocket,50000) == 0 );
}
while ( 1 );
return 0;
}
