/**
* Deal with ARP queries.
*
* @returns true if ARP.
*
* @param pSession The support driver session.
* @param hIf The internal network interface handle.
* @param pBuf The internal network interface buffer.
* @param pMacAddr Our MAC address.
* @param IPv4Addr Our IPv4 address.
*/
bool VBoxNetArpHandleIt(PSUPDRVSESSION pSession, INTNETIFHANDLE hIf, PINTNETBUF pBuf, PCRTMAC pMacAddr, RTNETADDRIPV4 IPv4Addr)
{
/*
* Valid IntNet Ethernet frame? Skip GSO, no ARP in there.
*/
PCINTNETHDR pHdr = IntNetRingGetNextFrameToRead(&pBuf->Recv);
if ( !pHdr
|| pHdr->u16Type != INTNETHDR_TYPE_FRAME)
return false;
size_t cbFrame = pHdr->cbFrame;
const void *pvFrame = IntNetHdrGetFramePtr(pHdr, pBuf);
PCRTNETETHERHDR pEthHdr = (PCRTNETETHERHDR)pvFrame;
/*
* Arp frame?
*/
if (pEthHdr->EtherType != RT_H2N_U16_C(RTNET_ETHERTYPE_ARP))
return false;
if ( ( pEthHdr->DstMac.au16[0] != 0xffff
|| pEthHdr->DstMac.au16[1] != 0xffff
|| pEthHdr->DstMac.au16[2] != 0xffff)
&& ( pEthHdr->DstMac.au16[0] != pMacAddr->au16[0]
|| pEthHdr->DstMac.au16[1] != pMacAddr->au16[1]
|| pEthHdr->DstMac.au16[2] != pMacAddr->au16[2])
)
return false;
if (cbFrame < sizeof(RTNETARPIPV4) + sizeof(RTNETETHERHDR))
return false;
PCRTNETARPHDR pArpHdr = (PCRTNETARPHDR)(pEthHdr + 1);
if (pArpHdr->ar_htype != RT_H2N_U16_C(RTNET_ARP_ETHER))
return false;
if (pArpHdr->ar_hlen != sizeof(RTMAC))
return false;
if (pArpHdr->ar_ptype != RT_H2N_U16_C(RTNET_ETHERTYPE_IPV4))
return false;
if (pArpHdr->ar_plen != sizeof(RTNETADDRIPV4))
return false;
/* It's ARP, alright. Anything we need to do something about. */
PCRTNETARPIPV4 pArp = (PCRTNETARPIPV4)pArpHdr;
switch (pArp->Hdr.ar_oper)
{
case RT_H2N_U16_C(RTNET_ARPOP_REQUEST):
case RT_H2N_U16_C(RTNET_ARPOP_REVREQUEST):
case RT_H2N_U16_C(RTNET_ARPOP_INVREQUEST):
break;
default:
return true;
}
/*
* Deal with the queries.
*/
RTNETARPIPV4 Reply;
switch (pArp->Hdr.ar_oper)
{
/* 'Who has ar_tpa? Tell ar_spa.' */
case RT_H2N_U16_C(RTNET_ARPOP_REQUEST):
if (pArp->ar_tpa.u != IPv4Addr.u)
return true;
Reply.Hdr.ar_oper = RT_H2N_U16_C(RTNET_ARPOP_REPLY);
break;
case RT_H2N_U16_C(RTNET_ARPOP_REVREQUEST):
if ( pArp->ar_tha.au16[0] != pMacAddr->au16[0]
|| pArp->ar_tha.au16[1] != pMacAddr->au16[1]
|| pArp->ar_tha.au16[2] != pMacAddr->au16[2])
return true;
Reply.Hdr.ar_oper = RT_H2N_U16_C(RTNET_ARPOP_REVREPLY);
break;
case RT_H2N_U16_C(RTNET_ARPOP_INVREQUEST):
/** @todo RTNET_ARPOP_INVREQUEST */
return true;
//Reply.Hdr.ar_oper = RT_H2N_U16_C(RTNET_ARPOP_INVREPLY);
//break;
}
/*
* Complete the reply and send it.
*/
Reply.Hdr.ar_htype = RT_H2N_U16_C(RTNET_ARP_ETHER);
Reply.Hdr.ar_ptype = RT_H2N_U16_C(RTNET_ETHERTYPE_IPV4);
Reply.Hdr.ar_hlen = sizeof(RTMAC);
Reply.Hdr.ar_plen = sizeof(RTNETADDRIPV4);
Reply.ar_sha = *pMacAddr;
Reply.ar_spa = IPv4Addr;
Reply.ar_tha = pArp->ar_sha;
Reply.ar_tpa = pArp->ar_spa;
RTNETETHERHDR EthHdr;
EthHdr.DstMac = pArp->ar_sha;
EthHdr.SrcMac = *pMacAddr;
EthHdr.EtherType = RT_H2N_U16_C(RTNET_ETHERTYPE_ARP);
uint8_t abTrailer[60 - sizeof(Reply) - sizeof(EthHdr)];
memset(abTrailer, '\0', sizeof(abTrailer));
INTNETSEG aSegs[3];
aSegs[0].cb = sizeof(EthHdr);
aSegs[0].pv = &EthHdr;
aSegs[1].pv = &Reply;
aSegs[1].cb = sizeof(Reply);
aSegs[2].pv = &abTrailer[0];
aSegs[2].cb = sizeof(abTrailer);
VBoxNetIntIfSend(pSession, hIf, pBuf, RT_ELEMENTS(aSegs), &aSegs[0], true /* fFlush */);
return true;
}
/** Internal worker for VBoxNetUDPUnicast and VBoxNetUDPBroadcast. */
static int vboxnetudpSend(PSUPDRVSESSION pSession, INTNETIFHANDLE hIf, PINTNETBUF pBuf,
RTNETADDRIPV4 SrcIPv4Addr, PCRTMAC pSrcMacAddr, unsigned uSrcPort,
RTNETADDRIPV4 DstIPv4Addr, PCRTMAC pDstMacAddr, unsigned uDstPort,
void const *pvData, size_t cbData)
{
INTNETSEG aSegs[4];
/* the Ethernet header */
RTNETETHERHDR EtherHdr;
EtherHdr.DstMac = *pDstMacAddr;
EtherHdr.SrcMac = *pSrcMacAddr;
EtherHdr.EtherType = RT_H2BE_U16_C(RTNET_ETHERTYPE_IPV4);
aSegs[0].pv = &EtherHdr;
aSegs[0].cb = sizeof(EtherHdr);
aSegs[0].Phys = NIL_RTHCPHYS;
/* the IP header */
RTNETIPV4 IpHdr;
unsigned cbIdHdr = RT_UOFFSETOF(RTNETIPV4, ip_options);
IpHdr.ip_v = 4;
IpHdr.ip_hl = cbIdHdr >> 2;
IpHdr.ip_tos = 0;
IpHdr.ip_len = RT_H2BE_U16((uint16_t)(cbData + sizeof(RTNETUDP) + cbIdHdr));
IpHdr.ip_id = (uint16_t)RTRandU32();
IpHdr.ip_off = 0;
IpHdr.ip_ttl = 255;
IpHdr.ip_p = RTNETIPV4_PROT_UDP;
IpHdr.ip_sum = 0;
IpHdr.ip_src = SrcIPv4Addr;
IpHdr.ip_dst = DstIPv4Addr;
IpHdr.ip_sum = RTNetIPv4HdrChecksum(&IpHdr);
aSegs[1].pv = &IpHdr;
aSegs[1].cb = cbIdHdr;
aSegs[1].Phys = NIL_RTHCPHYS;
/* the UDP bit */
RTNETUDP UdpHdr;
UdpHdr.uh_sport = RT_H2BE_U16(uSrcPort);
UdpHdr.uh_dport = RT_H2BE_U16(uDstPort);
UdpHdr.uh_ulen = RT_H2BE_U16((uint16_t)(cbData + sizeof(RTNETUDP)));
#if 0
UdpHdr.uh_sum = 0; /* pretend checksumming is disabled */
#else
UdpHdr.uh_sum = RTNetIPv4UDPChecksum(&IpHdr, &UdpHdr, pvData);
#endif
aSegs[2].pv = &UdpHdr;
aSegs[2].cb = sizeof(UdpHdr);
aSegs[2].Phys = NIL_RTHCPHYS;
/* the payload */
aSegs[3].pv = (void *)pvData;
aSegs[3].cb = (uint32_t)cbData;
aSegs[3].Phys = NIL_RTHCPHYS;
/* send it */
return VBoxNetIntIfSend(pSession, hIf, pBuf, RT_ELEMENTS(aSegs), &aSegs[0], true /* fFlush */);
}
