Example #1
0
int VBoxNetLwipNAT::processGSO(PCPDMNETWORKGSO pGso, size_t cbFrame)
{
    if (!PDMNetGsoIsValid(pGso, cbFrame,
                          cbFrame - sizeof(PDMNETWORKGSO)))
        return VERR_INVALID_PARAMETER;

    cbFrame -= sizeof(PDMNETWORKGSO);
    uint8_t         abHdrScratch[256];
    uint32_t const  cSegs = PDMNetGsoCalcSegmentCount(pGso,
                                                      cbFrame);
    for (size_t iSeg = 0; iSeg < cSegs; iSeg++)
    {
        uint32_t cbSegFrame;
        void    *pvSegFrame =
          PDMNetGsoCarveSegmentQD(pGso,
                                  (uint8_t *)(pGso + 1),
                                  cbFrame,
                                  abHdrScratch,
                                  iSeg,
                                  cSegs,
                                  &cbSegFrame);

        int rc = processFrame(pvSegFrame, cbSegFrame);
        if (RT_FAILURE(rc))
        {
            return rc;
        }
    }

    return VINF_SUCCESS;
}
Example #2
0
/**
 * Checks if the head of the receive ring is a UDP packet matching the given
 * criteria.
 *
 * @returns Pointer to the data if it matches.
 * @param   pBuf            The IntNet buffers.
 * @param   uDstPort        The destination port to match.
 * @param   pDstMac         The destination address to match if
 *                          VBOXNETUDP_MATCH_UNICAST is specied.
 * @param   fFlags          Flags indicating what to match and some debug stuff.
 *                          See VBOXNETUDP_MATCH_*.
 * @param   pHdrs           Where to return the pointers to the headers.
 *                          Optional.
 * @param   pcb             Where to return the size of the data on success.
 */
void *VBoxNetUDPMatch(PINTNETBUF pBuf, unsigned uDstPort, PCRTMAC pDstMac, uint32_t fFlags, PVBOXNETUDPHDRS pHdrs, size_t *pcb)
{
    /*
     * Clear return values so we can return easier on mismatch.
     */
    *pcb = 0;
    if (pHdrs)
    {
        pHdrs->pEth  = NULL;
        pHdrs->pIpv4 = NULL;
        pHdrs->pUdp  = NULL;
    }

    /*
     * Valid IntNet Ethernet frame?
     */
    PCINTNETHDR pHdr = IntNetRingGetNextFrameToRead(&pBuf->Recv);
    if (    !pHdr
        ||  (   pHdr->u16Type != INTNETHDR_TYPE_FRAME
             && pHdr->u16Type != INTNETHDR_TYPE_GSO))
        return NULL;

    size_t          cbFrame = pHdr->cbFrame;
    const void     *pvFrame = IntNetHdrGetFramePtr(pHdr, pBuf);
    PCPDMNETWORKGSO pGso    = NULL;
    if (pHdr->u16Type == INTNETHDR_TYPE_GSO)
    {
        pGso = (PCPDMNETWORKGSO)pvFrame;
        if (!PDMNetGsoIsValid(pGso, cbFrame, cbFrame - sizeof(*pGso)))
            return NULL;
        /** @todo IPv6 UDP support, goes for this entire function really.  Not really
         *        important yet since this is currently only used by the DHCP server. */
        if (pGso->u8Type != PDMNETWORKGSOTYPE_IPV4_UDP)
            return NULL;
        pvFrame  = pGso + 1;
        cbFrame -= sizeof(*pGso);
    }

    PCRTNETETHERHDR pEthHdr = (PCRTNETETHERHDR)pvFrame;
    if (pHdrs)
        pHdrs->pEth = pEthHdr;

#ifdef IN_RING3
    /* Dump if to stderr/log if that's wanted. */
    if (fFlags & VBOXNETUDP_MATCH_PRINT_STDERR)
    {
        RTStrmPrintf(g_pStdErr, "frame: cb=%04x dst=%.6Rhxs src=%.6Rhxs type=%04x%s\n",
                     cbFrame, &pEthHdr->DstMac, &pEthHdr->SrcMac, RT_BE2H_U16(pEthHdr->EtherType),
                     !memcmp(&pEthHdr->DstMac, pDstMac, sizeof(*pDstMac)) ? " Mine!" : "");
    }
#endif

    /*
     * Ethernet matching.
     */

    /* Ethernet min frame size. */
    if (cbFrame < 64)
        return NULL;

    /* Match Ethertype: IPV4? */
    /** @todo VLAN tagging? */
    if (pEthHdr->EtherType != RT_H2BE_U16_C(RTNET_ETHERTYPE_IPV4))
        return NULL;

    /* Match destination address (ethernet) */
    if (    (   !(fFlags & VBOXNETUDP_MATCH_UNICAST)
             || memcmp(&pEthHdr->DstMac, pDstMac, sizeof(pEthHdr->DstMac)))
        &&  (   !(fFlags & VBOXNETUDP_MATCH_BROADCAST)
             || pEthHdr->DstMac.au16[0] != 0xffff
             || pEthHdr->DstMac.au16[1] != 0xffff
             || pEthHdr->DstMac.au16[2] != 0xffff))
        return NULL;

    /*
     * If we're working on a GSO frame, we need to make sure the length fields
     * are set correctly (they are usually set to 0).
     */
    if (pGso)
        PDMNetGsoPrepForDirectUse(pGso, (void *)pvFrame, cbFrame, PDMNETCSUMTYPE_NONE);

    /*
     * IP validation and matching.
     */
    PCRTNETIPV4 pIpHdr = (PCRTNETIPV4)(pEthHdr + 1);
    if (pHdrs)
        pHdrs->pIpv4 = pIpHdr;

    /* Protocol: UDP */
    if (pIpHdr->ip_p != RTNETIPV4_PROT_UDP)
        return NULL;

    /* Valid IPv4 header? */
    size_t const offIpHdr = (uintptr_t)pIpHdr - (uintptr_t)pEthHdr;
    if (!RTNetIPv4IsHdrValid(pIpHdr, cbFrame - offIpHdr, cbFrame - offIpHdr, !pGso /*fChecksum*/))
        return NULL;

    /*
     * UDP matching and validation.
     */
    PCRTNETUDP  pUdpHdr   = (PCRTNETUDP)((uint32_t *)pIpHdr + pIpHdr->ip_hl);
    if (pHdrs)
        pHdrs->pUdp = pUdpHdr;

    /* Destination port */
    if (RT_BE2H_U16(pUdpHdr->uh_dport) != uDstPort)
        return NULL;

    if (!pGso)
    {
        /* Validate the UDP header according to flags. */
        size_t      offUdpHdr = (uintptr_t)pUdpHdr - (uintptr_t)pEthHdr;
        if (fFlags & (VBOXNETUDP_MATCH_CHECKSUM | VBOXNETUDP_MATCH_REQUIRE_CHECKSUM))
        {
            if (!RTNetIPv4IsUDPValid(pIpHdr, pUdpHdr, pUdpHdr + 1, cbFrame - offUdpHdr, true /*fChecksum*/))
                return NULL;
            if (    (fFlags & VBOXNETUDP_MATCH_REQUIRE_CHECKSUM)
                &&  !pUdpHdr->uh_sum)
                return NULL;
        }
        else
        {
            if (!RTNetIPv4IsUDPSizeValid(pIpHdr, pUdpHdr, cbFrame - offUdpHdr))
                return NULL;
        }
    }

    /*
     * We've got a match!
     */
    *pcb = pUdpHdr->uh_ulen - sizeof(*pUdpHdr);
    return (void *)(pUdpHdr + 1);
}