pdmnetinline.h revision 57badba2aa42678ef6da31e938f2e6f61d056572
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync/* $Id$ */
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync/** @file
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * PDM - Networking Helpers, Inlined Code. (DEV,++)
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync *
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * This is all inlined because it's too tedious to create 2-3 libraries to
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * contain it all (same bad excuse as for intnetinline.h). C++ only because of
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * mixed code and variables.
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync */
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync/*
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * Copyright (C) 2010 Sun Microsystems, Inc.
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync *
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * This file is part of VirtualBox Open Source Edition (OSE), as
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * available from http://www.virtualbox.org. This file is free software;
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * you can redistribute it and/or modify it under the terms of the GNU
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * General Public License (GPL) as published by the Free Software
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * Foundation, in version 2 as it comes in the "COPYING" file of the
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync *
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * Clara, CA 95054 USA or visit http://www.sun.com if you need
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * additional information or have any questions.
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync */
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync/*******************************************************************************
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync* Header Files *
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync*******************************************************************************/
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync#include <VBox/log.h>
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync#include <VBox/types.h>
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync#include <iprt/asm.h>
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync#include <iprt/assert.h>
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync#include <iprt/net.h>
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync#include <iprt/string.h>
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync/**
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * Validates the GSO context.
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync *
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * @returns true if valid, false if not (not asserted or logged).
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * @param pGso The GSO context.
deb4998ba50060c48cce222fd18a8eed053918d7vboxsync * @param cbGsoMax The max size of the GSO context.
* @param cbFrame The max size of the GSO frame (use to validate
* the MSS).
*/
DECLINLINE(bool) PDMNetGsoIsValid(PCPDMNETWORKGSO pGso, size_t cbGsoMax, size_t cbFrame)
{
if (RT_UNLIKELY(cbGsoMax < sizeof(*pGso)))
return false;
PDMNETWORKGSOTYPE const enmType = (PDMNETWORKGSOTYPE)pGso->u8Type;
if (RT_UNLIKELY( enmType <= PDMNETWORKGSOTYPE_INVALID || enmType >= PDMNETWORKGSOTYPE_END ))
return false;
/* all types requires both headers. */
if (RT_UNLIKELY( pGso->offHdr1 < sizeof(RTNETETHERHDR) ))
return false;
if (RT_UNLIKELY( pGso->offHdr2 <= pGso->offHdr1 ))
return false;
if (RT_UNLIKELY( pGso->cbHdrs <= pGso->offHdr2 ))
return false;
/* min size of the 1st header(s). */
switch (enmType)
{
case PDMNETWORKGSOTYPE_IPV4_TCP:
case PDMNETWORKGSOTYPE_IPV4_UDP:
if (RT_UNLIKELY( (unsigned)pGso->offHdr2 - pGso->offHdr1 < RTNETIPV4_MIN_LEN ))
return false;
break;
case PDMNETWORKGSOTYPE_IPV6_TCP:
case PDMNETWORKGSOTYPE_IPV6_UDP:
if (RT_UNLIKELY( (unsigned)pGso->offHdr2 - pGso->offHdr1 < RTNETIPV6_MIN_LEN ))
return false;
break;
case PDMNETWORKGSOTYPE_IPV4_IPV6_TCP:
case PDMNETWORKGSOTYPE_IPV4_IPV6_UDP:
if (RT_UNLIKELY( (unsigned)pGso->offHdr2 - pGso->offHdr1 < RTNETIPV4_MIN_LEN + RTNETIPV6_MIN_LEN ))
return false;
break;
case PDMNETWORKGSOTYPE_INVALID:
case PDMNETWORKGSOTYPE_END:
break;
/* no default case! want gcc warnings. */
}
/* min size of the 2nd header. */
switch (enmType)
{
case PDMNETWORKGSOTYPE_IPV4_TCP:
case PDMNETWORKGSOTYPE_IPV6_TCP:
case PDMNETWORKGSOTYPE_IPV4_IPV6_TCP:
if (RT_UNLIKELY( (unsigned)pGso->cbHdrs - pGso->offHdr2 < RTNETTCP_MIN_LEN ))
return false;
break;
case PDMNETWORKGSOTYPE_IPV4_UDP:
case PDMNETWORKGSOTYPE_IPV6_UDP:
case PDMNETWORKGSOTYPE_IPV4_IPV6_UDP:
if (RT_UNLIKELY( (unsigned)pGso->cbHdrs - pGso->offHdr2 < RTNETUDP_MIN_LEN ))
return false;
break;
case PDMNETWORKGSOTYPE_INVALID:
case PDMNETWORKGSOTYPE_END:
break;
/* no default case! want gcc warnings. */
}
/* There must be at more than one segment. */
if (RT_UNLIKELY( cbFrame <= pGso->cbHdrs ))
return false;
if (RT_UNLIKELY( cbFrame - pGso->cbHdrs < pGso->cbMaxSeg ))
return false;
return true;
}
/**
* Calculates the number of segements a GSO frame will be segmented into.
*
* @returns Segment count.
* @param pGso The GSO context.
* @param cbFrame The GSO frame size (header proto + payload).
*/
DECLINLINE(uint32_t) PDMNetGsoCalcSegmentCount(PCPDMNETWORKGSO pGso, size_t cbFrame)
{
Assert(PDMNetGsoIsValid(pGso, sizeof(*pGso), cbFrame));
size_t cbPayload = cbFrame - pGso->cbHdrs;
return (uint32_t)((cbPayload + pGso->cbMaxSeg - 1) / pGso->cbMaxSeg);
}
/**
* Used to find the IPv6 header when handling 4to6 tunneling.
*
* @returns Offset of the IPv6 header.
* @param pbSegHdrs The headers / frame start.
* @param offIpHdr The offset of the IPv4 header.
*/
DECLINLINE(uint8_t) pgmNetGsoCalcIpv6Offset(uint8_t *pbSegHdrs, uint8_t offIPv4Hdr)
{
PCRTNETIPV4 pIPv4Hdr = (PCRTNETIPV4)&pbSegHdrs[offIPv4Hdr];
return offIPv4Hdr + pIPv4Hdr->ip_hl * 4;
}
/**
* Update an UDP header after carving out a segment
*
* @param u32PsudoSum The pseudo checksum.
* @param pbSegHdrs Pointer to the header bytes / frame start.
* @param offUdpHdr The offset into @a pbSegHdrs of the UDP header.
* @param pbPayload Pointer to the payload bytes.
* @param cbPayload The amount of payload.
* @param cbHdrs The size of all the headers.
* @internal
*/
DECLINLINE(void) pdmNetGsoUpdateUdpHdr(uint32_t u32PsudoSum, uint8_t *pbSegHdrs, uint8_t offUdpHdr,
uint8_t const *pbPayload, uint32_t cbPayload, uint8_t cbHdrs)
{
PRTNETUDP pUdpHdr = (PRTNETUDP)&pbSegHdrs[offUdpHdr];
pUdpHdr->uh_ulen = cbPayload + cbHdrs - offUdpHdr;
pUdpHdr->uh_sum = RTNetUDPChecksum(u32PsudoSum, pUdpHdr);
}
/**
* Update a TCP header after carving out a segment.
*
* @param u32PsudoSum The pseudo checksum.
* @param pbSegHdrs Pointer to the header bytes / frame start.
* @param offTcpHdr The offset into @a pbSegHdrs of the TCP header.
* @param pbPayload Pointer to the payload bytes.
* @param cbPayload The amount of payload.
* @param offPayload The offset into the payload that we're splitting
* up. We're ASSUMING that the payload follows
* immediately after the TCP header w/ options.
* @param cbHdrs The size of all the headers.
* @param fLastSeg Set if this is the last segment.
* @internal
*/
DECLINLINE(void) pdmNetGsoUpdateTcpHdr(uint32_t u32PsudoSum, uint8_t *pbSegHdrs, uint8_t offTcpHdr,
uint8_t const *pbPayload, uint32_t cbPayload, uint32_t offPayload, uint8_t cbHdrs, bool fLastSeg)
{
PRTNETTCP pTcpHdr = (PRTNETTCP)&pbSegHdrs[offTcpHdr];
pTcpHdr->th_seq = RT_H2N_U32(RT_N2H_U32(pTcpHdr->th_seq) + offPayload);
if (!fLastSeg)
pTcpHdr->th_flags &= ~(RTNETTCP_F_FIN | RTNETTCP_F_PSH);
pTcpHdr->th_sum = RTNetTCPChecksum(u32PsudoSum, pTcpHdr, pbPayload, cbPayload);
}
/**
* Updates a IPv6 header after carving out a segment.
*
* @returns 32-bit intermediary checksum value for the pseudo header.
* @param pbSegHdrs Pointer to the header bytes.
* @param offIpHdr The offset into @a pbSegHdrs of the IP header.
* @param cbSegPayload The amount of segmented payload. Not to be
* confused with the IP payload.
* @param cbHdrs The size of all the headers.
* @param offPktHdr Offset of the protocol packet header. For the
* pseudo header checksum calulation.
* @param bProtocol The protocol type. For the pseudo header.
* @internal
*/
DECLINLINE(uint32_t) pdmNetGsoUpdateIPv6Hdr(uint8_t *pbSegHdrs, uint8_t offIpHdr, uint32_t cbSegPayload, uint8_t cbHdrs,
uint8_t offPktHdr, uint8_t bProtocol)
{
PRTNETIPV6 pIpHdr = (PRTNETIPV6)&pbSegHdrs[offIpHdr];
uint16_t cbPayload = (uint16_t)(cbHdrs - (offIpHdr + sizeof(RTNETIPV6)) + cbSegPayload);
pIpHdr->ip6_plen = RT_H2N_U16(cbPayload);
return RTNetIPv6PseudoChecksumEx(pIpHdr, bProtocol, (uint16_t)(cbHdrs - offPktHdr + cbSegPayload));
}
/**
* Updates a IPv4 header after carving out a segment.
*
* @returns 32-bit intermediary checksum value for the pseudo header.
* @param pbSegHdrs Pointer to the header bytes.
* @param offIpHdr The offset into @a pbSegHdrs of the IP header.
* @param cbSegPayload The amount of segmented payload.
* @param iSeg The segment index.
* @param cbHdrs The size of all the headers.
* @internal
*/
DECLINLINE(uint32_t) pdmNetGsoUpdateIPv4Hdr(uint8_t *pbSegHdrs, uint8_t offIpHdr, uint32_t cbSegPayload,
uint32_t iSeg, uint8_t cbHdrs)
{
PRTNETIPV4 pIpHdr = (PRTNETIPV4)&pbSegHdrs[offIpHdr];
pIpHdr->ip_len = RT_H2N_U16(cbHdrs - offIpHdr + cbSegPayload);
pIpHdr->ip_id = RT_H2N_U16(RT_N2H_U16(pIpHdr->ip_id) + iSeg);
pIpHdr->ip_sum = RT_H2N_U16(RTNetIPv4HdrChecksum(pIpHdr));
return RTNetIPv4PseudoChecksum(pIpHdr);
}
/**
* Carves out the specified segment in a destructive manner.
*
* This is for sequentially carving out segments and pushing them along for
* processing or sending. To avoid allocating a temporary buffer for
* constructing the segment in, we trash the previous frame by putting the
* header at the end of it.
*
* @returns Pointer to the segment frame that we've carved out.
* @param pGso The GSO context data.
* @param pbFrame Pointer to the GSO frame.
* @param cbFrame The size of the GSO frame.
* @param pbHdrScatch Pointer to a pGso->cbHdrs sized area where we
* can save the original header prototypes on the
* first call (@a iSeg is 0) and retrieve it on
* susequent calls. (Just use a 256 bytes
* buffer to make life easy.)
* @param iSeg The segment that we're carving out (0-based).
* @param cSegs The number of segments in the GSO frame. Use
* PDMNetGsoCalcSegmentCount to find this.
* @param pcbSegFrame Where to return the size of the returned segment
* frame.
*/
DECLINLINE(void *) PDMNetGsoCarveSegmentQD(PCPDMNETWORKGSO pGso, uint8_t *pbFrame, size_t cbFrame, uint8_t *pbHdrScatch,
uint32_t iSeg, uint32_t cSegs, uint32_t *pcbSegFrame)
{
/*
* Check assumptions.
*/
Assert(iSeg < cSegs);
Assert(cSegs == PDMNetGsoCalcSegmentCount(pGso, cbFrame));
Assert(PDMNetGsoIsValid(pGso, sizeof(*pGso), cbFrame));
/*
* Figure out where the payload is and where the header starts before we
* do the protocol specific carving.
*/
uint8_t * const pbSegHdrs = pbFrame + pGso->cbMaxSeg * iSeg;
uint8_t * const pbSegPayload = pbSegHdrs + pGso->cbHdrs;
uint32_t const cbSegPayload = iSeg + 1 != cSegs
? pGso->cbMaxSeg
: (uint32_t)(cbFrame - iSeg * pGso->cbMaxSeg - pGso->cbHdrs);
uint32_t const cbSegFrame = cbSegPayload + pGso->cbHdrs;
/*
* Copy the header and do the protocol specific massaging of it.
*/
if (iSeg != 0)
memcpy(pbSegHdrs, pbHdrScatch, pGso->cbHdrs);
else
memcpy(pbHdrScatch, pbSegHdrs, pGso->cbHdrs);
switch ((PDMNETWORKGSOTYPE)pGso->u8Type)
{
case PDMNETWORKGSOTYPE_IPV4_TCP:
pdmNetGsoUpdateTcpHdr(pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, iSeg * pGso->cbMaxSeg,
pGso->cbHdrs, iSeg + 1 == cSegs);
break;
case PDMNETWORKGSOTYPE_IPV4_UDP:
pdmNetGsoUpdateUdpHdr(pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, pGso->cbHdrs);
break;
case PDMNETWORKGSOTYPE_IPV6_TCP:
pdmNetGsoUpdateTcpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, pGso->cbHdrs,
pGso->offHdr2, RTNETIPV4_PROT_TCP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, iSeg * pGso->cbMaxSeg,
pGso->cbHdrs, iSeg + 1 == cSegs);
break;
case PDMNETWORKGSOTYPE_IPV6_UDP:
pdmNetGsoUpdateUdpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, pGso->cbHdrs,
pGso->offHdr2, RTNETIPV4_PROT_UDP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, pGso->cbHdrs);
break;
case PDMNETWORKGSOTYPE_IPV4_IPV6_TCP:
pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs);
pdmNetGsoUpdateTcpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pgmNetGsoCalcIpv6Offset(pbSegHdrs, pGso->offHdr1),
cbSegPayload, pGso->cbHdrs, pGso->offHdr2, RTNETIPV4_PROT_TCP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, iSeg * pGso->cbMaxSeg,
pGso->cbHdrs, iSeg + 1 == cSegs);
break;
case PDMNETWORKGSOTYPE_IPV4_IPV6_UDP:
pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs);
pdmNetGsoUpdateUdpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pgmNetGsoCalcIpv6Offset(pbSegHdrs, pGso->offHdr1),
cbSegPayload, pGso->cbHdrs, pGso->offHdr2, RTNETIPV4_PROT_UDP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, pGso->cbHdrs);
break;
case PDMNETWORKGSOTYPE_INVALID:
case PDMNETWORKGSOTYPE_END:
/* no default! wnat gcc warnings. */
break;
}
*pcbSegFrame = cbSegPayload + pGso->cbHdrs;
return pbSegHdrs;
}
/**
* Carves out the specified segment in a non-destructive manner.
*
* The segment headers and segment payload is kept separate here. The GSO frame
* is still expected to be one linear chunk of data, but we don't modify any of
* it.
*
* @returns The offset into the GSO frame of the payload.
* @param pGso The GSO context data.
* @param pbFrame Pointer to the GSO frame. Used for retriving
* the header prototype and for checksumming the
* payload. The buffer is not modified.
* @param cbFrame The size of the GSO frame.
* @param iSeg The segment that we're carving out (0-based).
* @param cSegs The number of segments in the GSO frame. Use
* PDMNetGsoCalcSegmentCount to find this.
* @param pbSegHdrs Where to return the headers for the segment
* that's been carved out. The buffer must be at
* least pGso->cbHdrs in size, using a 256 byte
* buffer is a recommended simplification.
* @param pcbSegPayload Where to return the size of the returned
* segment payload.
*/
DECLINLINE(uint32_t) PDMNetGsoCarveSegment(PCPDMNETWORKGSO pGso, const uint8_t *pbFrame, size_t cbFrame,
uint32_t iSeg, uint32_t cSegs, uint8_t *pbSegHdrs, uint32_t *pcbSegPayload)
{
/*
* Check assumptions.
*/
Assert(iSeg < cSegs);
Assert(cSegs == PDMNetGsoCalcSegmentCount(pGso, cbFrame));
Assert(PDMNetGsoIsValid(pGso, sizeof(*pGso), cbFrame));
/*
* Figure out where the payload is and where the header starts before we
* do the protocol specific carving.
*/
uint8_t const * const pbSegPayload = pbFrame + pGso->cbHdrs + iSeg * pGso->cbMaxSeg;
uint32_t const cbSegPayload = iSeg + 1 != cSegs
? pGso->cbMaxSeg
: (uint32_t)(cbFrame - iSeg * pGso->cbMaxSeg - pGso->cbHdrs);
/*
* Copy the header and do the protocol specific massaging of it.
*/
memcpy(pbSegHdrs, pbFrame, pGso->cbHdrs);
switch ((PDMNETWORKGSOTYPE)pGso->u8Type)
{
case PDMNETWORKGSOTYPE_IPV4_TCP:
pdmNetGsoUpdateTcpHdr(pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, iSeg * pGso->cbMaxSeg,
pGso->cbHdrs, iSeg + 1 == cSegs);
break;
case PDMNETWORKGSOTYPE_IPV4_UDP:
pdmNetGsoUpdateUdpHdr(pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, pGso->cbHdrs);
break;
case PDMNETWORKGSOTYPE_IPV6_TCP:
pdmNetGsoUpdateTcpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, pGso->cbHdrs,
pGso->offHdr2, RTNETIPV4_PROT_TCP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, iSeg * pGso->cbMaxSeg,
pGso->cbHdrs, iSeg + 1 == cSegs);
break;
case PDMNETWORKGSOTYPE_IPV6_UDP:
pdmNetGsoUpdateUdpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, pGso->cbHdrs,
pGso->offHdr2, RTNETIPV4_PROT_UDP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, pGso->cbHdrs);
break;
case PDMNETWORKGSOTYPE_IPV4_IPV6_TCP:
pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs);
pdmNetGsoUpdateTcpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pgmNetGsoCalcIpv6Offset(pbSegHdrs, pGso->offHdr1),
cbSegPayload, pGso->cbHdrs, pGso->offHdr2, RTNETIPV4_PROT_TCP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, iSeg * pGso->cbMaxSeg,
pGso->cbHdrs, iSeg + 1 == cSegs);
break;
case PDMNETWORKGSOTYPE_IPV4_IPV6_UDP:
pdmNetGsoUpdateIPv4Hdr(pbSegHdrs, pGso->offHdr1, cbSegPayload, iSeg, pGso->cbHdrs);
pdmNetGsoUpdateUdpHdr(pdmNetGsoUpdateIPv6Hdr(pbSegHdrs, pgmNetGsoCalcIpv6Offset(pbSegHdrs, pGso->offHdr1),
cbSegPayload, pGso->cbHdrs, pGso->offHdr2, RTNETIPV4_PROT_UDP),
pbSegHdrs, pGso->offHdr2, pbSegPayload, cbSegPayload, pGso->cbHdrs);
break;
case PDMNETWORKGSOTYPE_INVALID:
case PDMNETWORKGSOTYPE_END:
/* no default! wnat gcc warnings. */
break;
}
*pcbSegPayload = cbSegPayload;
return pGso->cbHdrs + iSeg * pGso->cbMaxSeg;
}
DECLINLINE(void) PDMNetGsoPrepForDirectUse(PCPDMNETWORKGSO pGso, void *pvFrame, size_t cbFrame,
bool fHeaderChecskum, bool fPayloadChecksum)
{
/** @todo Need to implement this eventually, not important yet as it's only use
* by DHCP where GSO isn't normally used. */
}