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619 lines
23 KiB
C
619 lines
23 KiB
C
/*
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* This file contains SW Implementation of checksum computation for IP,TCP,UDP
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*
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* Copyright (c) 2008-2017 Red Hat, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met :
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and / or other materials provided with the distribution.
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* 3. Neither the names of the copyright holders nor the names of their contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED.IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include "ndis56common.h"
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#ifdef WPP_EVENT_TRACING
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#include "sw-offload.tmh"
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#endif
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#include <sal.h>
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// till IP header size is 8 bit
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#define MAX_SUPPORTED_IPV6_HEADERS (256 - 4)
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typedef ULONG IPV6_ADDRESS[4];
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// IPv6 Header RFC 2460 (40 bytes)
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typedef struct _tagIPv6Header {
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UCHAR ip6_ver_tc; // traffic class(low nibble), version (high nibble)
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UCHAR ip6_tc_fl; // traffic class(high nibble), flow label
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USHORT ip6_fl; // flow label, the rest
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USHORT ip6_payload_len; // length of following headers and payload
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UCHAR ip6_next_header; // next header type
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UCHAR ip6_hoplimit; // hop limit
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IPV6_ADDRESS ip6_src_address; //
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IPV6_ADDRESS ip6_dst_address; //
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} IPv6Header;
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typedef union
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{
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IPv6Header v6;
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IPv4Header v4;
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} IPHeader;
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// IPv6 Header RFC 2460 (n*8 bytes)
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typedef struct _tagIPv6ExtHeader {
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UCHAR ip6ext_next_header; // next header type
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UCHAR ip6ext_hdr_len; // length of this header in 8 bytes unit, not including first 8 bytes
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USHORT options; //
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} IPv6ExtHeader;
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// IP Pseudo Header RFC 768
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typedef struct _tagIPv4PseudoHeader {
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ULONG ipph_src; // Source address
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ULONG ipph_dest; // Destination address
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UCHAR ipph_zero; // 0
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UCHAR ipph_protocol; // TCP/UDP
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USHORT ipph_length; // TCP/UDP length
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}tIPv4PseudoHeader;
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// IPv6 Pseudo Header RFC 2460
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typedef struct _tagIPv6PseudoHeader {
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IPV6_ADDRESS ipph_src; // Source address
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IPV6_ADDRESS ipph_dest; // Destination address
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ULONG ipph_length; // TCP/UDP length
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UCHAR z1; // 0
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UCHAR z2; // 0
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UCHAR z3; // 0
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UCHAR ipph_protocol; // TCP/UDP
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}tIPv6PseudoHeader;
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#define PROTOCOL_TCP 6
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#define PROTOCOL_UDP 17
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#define IP_HEADER_LENGTH(pHeader) (((pHeader)->ip_verlen & 0x0F) << 2)
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#define TCP_HEADER_LENGTH(pHeader) ((pHeader->tcp_flags & 0xF0) >> 2)
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static __inline USHORT CheckSumCalculator(ULONG val, PVOID buffer, ULONG len)
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{
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PUSHORT pus = (PUSHORT)buffer;
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ULONG count = len >> 1;
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while (count--) val += *pus++;
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if (len & 1) val += (USHORT)*(PUCHAR)pus;
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val = (((val >> 16) | (val << 16)) + val) >> 16;
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return (USHORT)~val;
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}
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/******************************************
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IP header checksum calculator
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*******************************************/
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static __inline VOID CalculateIpChecksum(IPv4Header *pIpHeader)
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{
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pIpHeader->ip_xsum = 0;
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pIpHeader->ip_xsum = CheckSumCalculator(0, pIpHeader, IP_HEADER_LENGTH(pIpHeader));
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}
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static __inline tTcpIpPacketParsingResult
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ProcessTCPHeader(tTcpIpPacketParsingResult _res, PVOID pIpHeader, ULONG len, USHORT ipHeaderSize)
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{
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ULONG tcpipDataAt;
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tTcpIpPacketParsingResult res = _res;
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tcpipDataAt = ipHeaderSize + sizeof(TCPHeader);
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res.xxpStatus = ppresXxpIncomplete;
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res.TcpUdp = ppresIsTCP;
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if (len >= tcpipDataAt)
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{
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TCPHeader *pTcpHeader = (TCPHeader *)RtlOffsetToPointer(pIpHeader, ipHeaderSize);
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res.xxpStatus = ppresXxpKnown;
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tcpipDataAt = ipHeaderSize + TCP_HEADER_LENGTH(pTcpHeader);
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res.XxpIpHeaderSize = tcpipDataAt;
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}
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else
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{
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DPrintf(2, ("tcp: %d < min headers %d", len, tcpipDataAt));
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}
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return res;
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}
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static __inline tTcpIpPacketParsingResult
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ProcessUDPHeader(tTcpIpPacketParsingResult _res, PVOID pIpHeader, ULONG len, USHORT ipHeaderSize)
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{
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tTcpIpPacketParsingResult res = _res;
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ULONG udpDataStart = ipHeaderSize + sizeof(UDPHeader);
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res.xxpStatus = ppresXxpIncomplete;
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res.TcpUdp = ppresIsUDP;
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res.XxpIpHeaderSize = udpDataStart;
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if (len >= udpDataStart)
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{
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UDPHeader *pUdpHeader = (UDPHeader *)RtlOffsetToPointer(pIpHeader, ipHeaderSize);
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USHORT datagramLength = swap_short(pUdpHeader->udp_length);
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res.xxpStatus = ppresXxpKnown;
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// may be full or not, but the datagram length is known
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DPrintf(2, ("udp: len %d, datagramLength %d", len, datagramLength));
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}
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return res;
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}
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static __inline tTcpIpPacketParsingResult
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QualifyIpPacket(IPHeader *pIpHeader, ULONG len)
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{
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tTcpIpPacketParsingResult res;
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UCHAR ver_len = pIpHeader->v4.ip_verlen;
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UCHAR ip_version = (ver_len & 0xF0) >> 4;
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USHORT ipHeaderSize = 0;
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USHORT fullLength = 0;
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res.value = 0;
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if (ip_version == 4)
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{
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ipHeaderSize = (ver_len & 0xF) << 2;
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fullLength = swap_short(pIpHeader->v4.ip_length);
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DPrintf(3, ("ip_version %d, ipHeaderSize %d, protocol %d, iplen %d",
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ip_version, ipHeaderSize, pIpHeader->v4.ip_protocol, fullLength));
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res.ipStatus = (ipHeaderSize >= sizeof(IPv4Header)) ? ppresIPV4 : ppresNotIP;
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if (len < ipHeaderSize) res.ipCheckSum = ppresIPTooShort;
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if (fullLength) {}
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else
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{
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DPrintf(2, ("ip v.%d, iplen %d", ip_version, fullLength));
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}
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}
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else if (ip_version == 6)
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{
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UCHAR nextHeader = pIpHeader->v6.ip6_next_header;
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BOOLEAN bParsingDone = FALSE;
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ipHeaderSize = sizeof(pIpHeader->v6);
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res.ipStatus = ppresIPV6;
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res.ipCheckSum = ppresCSOK;
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fullLength = swap_short(pIpHeader->v6.ip6_payload_len);
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fullLength += ipHeaderSize;
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while (nextHeader != 59)
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{
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IPv6ExtHeader *pExt;
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switch (nextHeader)
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{
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case PROTOCOL_TCP:
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bParsingDone = TRUE;
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res.xxpStatus = ppresXxpKnown;
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res.TcpUdp = ppresIsTCP;
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res.xxpFull = len >= fullLength ? 1 : 0;
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res = ProcessTCPHeader(res, pIpHeader, len, ipHeaderSize);
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break;
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case PROTOCOL_UDP:
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bParsingDone = TRUE;
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res.xxpStatus = ppresXxpKnown;
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res.TcpUdp = ppresIsUDP;
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res.xxpFull = len >= fullLength ? 1 : 0;
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res = ProcessUDPHeader(res, pIpHeader, len, ipHeaderSize);
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break;
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//existing extended headers
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case 0:
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__fallthrough;
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case 60:
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__fallthrough;
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case 43:
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__fallthrough;
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case 44:
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__fallthrough;
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case 51:
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__fallthrough;
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case 50:
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__fallthrough;
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case 135:
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if (len >= ((ULONG)ipHeaderSize + 8))
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{
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pExt = (IPv6ExtHeader *)((PUCHAR)pIpHeader + ipHeaderSize);
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nextHeader = pExt->ip6ext_next_header;
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ipHeaderSize += 8;
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ipHeaderSize += pExt->ip6ext_hdr_len * 8;
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}
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else
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{
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DPrintf(0, ("[%s] ERROR: Break in the middle of ext. headers(len %d, hdr > %d)", __FUNCTION__, len, ipHeaderSize));
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res.ipStatus = ppresNotIP;
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bParsingDone = TRUE;
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}
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break;
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//any other protocol
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default:
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res.xxpStatus = ppresXxpOther;
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bParsingDone = TRUE;
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break;
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}
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if (bParsingDone)
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break;
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}
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if (ipHeaderSize <= MAX_SUPPORTED_IPV6_HEADERS)
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{
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DPrintf(3, ("ip_version %d, ipHeaderSize %d, protocol %d, iplen %d",
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ip_version, ipHeaderSize, nextHeader, fullLength));
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res.ipHeaderSize = ipHeaderSize;
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}
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else
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{
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DPrintf(0, ("[%s] ERROR: IP chain is too large (%d)", __FUNCTION__, ipHeaderSize));
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res.ipStatus = ppresNotIP;
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}
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}
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if (res.ipStatus == ppresIPV4)
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{
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res.ipHeaderSize = ipHeaderSize;
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res.xxpFull = len >= fullLength ? 1 : 0;
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// bit "more fragments" or fragment offset mean the packet is fragmented
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res.IsFragment = (pIpHeader->v4.ip_offset & ~0xC0) != 0;
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switch (pIpHeader->v4.ip_protocol)
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{
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case PROTOCOL_TCP:
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{
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res = ProcessTCPHeader(res, pIpHeader, len, ipHeaderSize);
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}
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break;
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case PROTOCOL_UDP:
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{
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res = ProcessUDPHeader(res, pIpHeader, len, ipHeaderSize);
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}
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break;
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default:
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res.xxpStatus = ppresXxpOther;
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break;
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}
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}
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return res;
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}
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static __inline USHORT GetXxpHeaderAndPayloadLen(IPHeader *pIpHeader, tTcpIpPacketParsingResult res)
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{
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if (res.ipStatus == ppresIPV4)
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{
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USHORT headerLength = IP_HEADER_LENGTH(&pIpHeader->v4);
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USHORT len = swap_short(pIpHeader->v4.ip_length);
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return len - headerLength;
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}
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if (res.ipStatus == ppresIPV6)
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{
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USHORT fullLength = swap_short(pIpHeader->v6.ip6_payload_len);
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return fullLength + sizeof(pIpHeader->v6) - (USHORT)res.ipHeaderSize;
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}
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return 0;
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}
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static __inline USHORT CalculateIpv4PseudoHeaderChecksum(IPv4Header *pIpHeader, USHORT headerAndPayloadLen)
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{
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tIPv4PseudoHeader ipph;
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USHORT checksum;
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ipph.ipph_src = pIpHeader->ip_src;
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ipph.ipph_dest = pIpHeader->ip_dest;
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ipph.ipph_zero = 0;
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ipph.ipph_protocol = pIpHeader->ip_protocol;
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ipph.ipph_length = swap_short(headerAndPayloadLen);
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checksum = CheckSumCalculator(0, &ipph, sizeof(ipph));
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return ~checksum;
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}
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static __inline USHORT CalculateIpv6PseudoHeaderChecksum(IPv6Header *pIpHeader, USHORT headerAndPayloadLen)
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{
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tIPv6PseudoHeader ipph;
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USHORT checksum;
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ipph.ipph_src[0] = pIpHeader->ip6_src_address[0];
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ipph.ipph_src[1] = pIpHeader->ip6_src_address[1];
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ipph.ipph_src[2] = pIpHeader->ip6_src_address[2];
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ipph.ipph_src[3] = pIpHeader->ip6_src_address[3];
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ipph.ipph_dest[0] = pIpHeader->ip6_dst_address[0];
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ipph.ipph_dest[1] = pIpHeader->ip6_dst_address[1];
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ipph.ipph_dest[2] = pIpHeader->ip6_dst_address[2];
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ipph.ipph_dest[3] = pIpHeader->ip6_dst_address[3];
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ipph.z1 = ipph.z2 = ipph.z3 = 0;
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ipph.ipph_protocol = pIpHeader->ip6_next_header;
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ipph.ipph_length = swap_short(headerAndPayloadLen);
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checksum = CheckSumCalculator(0, &ipph, sizeof(ipph));
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return ~checksum;
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}
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static __inline USHORT CalculateIpPseudoHeaderChecksum(IPHeader *pIpHeader,
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tTcpIpPacketParsingResult res,
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USHORT headerAndPayloadLen)
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{
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if (res.ipStatus == ppresIPV4)
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return CalculateIpv4PseudoHeaderChecksum(&pIpHeader->v4, headerAndPayloadLen);
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if (res.ipStatus == ppresIPV6)
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return CalculateIpv6PseudoHeaderChecksum(&pIpHeader->v6, headerAndPayloadLen);
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return 0;
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}
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static __inline BOOLEAN
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CompareNetCheckSumOnEndSystem(USHORT computedChecksum, USHORT arrivedChecksum)
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{
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//According to RFC 1624 sec. 3
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//Checksum verification mechanism should treat 0xFFFF
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//checksum value from received packet as 0x0000
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if(arrivedChecksum == 0xFFFF)
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arrivedChecksum = 0;
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return computedChecksum == arrivedChecksum;
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}
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/******************************************
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Calculates IP header checksum calculator
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it can be already calculated
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the header must be complete!
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*******************************************/
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static __inline tTcpIpPacketParsingResult
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VerifyIpChecksum(
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IPv4Header *pIpHeader,
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tTcpIpPacketParsingResult known,
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BOOLEAN bFix)
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{
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tTcpIpPacketParsingResult res = known;
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if (res.ipCheckSum != ppresIPTooShort)
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{
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USHORT saved = pIpHeader->ip_xsum;
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CalculateIpChecksum(pIpHeader);
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res.ipCheckSum = CompareNetCheckSumOnEndSystem(pIpHeader->ip_xsum, saved) ? ppresCSOK : ppresCSBad;
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if (!bFix)
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pIpHeader->ip_xsum = saved;
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else
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res.fixedIpCS = res.ipCheckSum == ppresCSBad;
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}
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return res;
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}
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/*********************************************
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Calculates UDP checksum, assuming the checksum field
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is initialized with pseudoheader checksum
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**********************************************/
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static VOID CalculateUdpChecksumGivenPseudoCS(UDPHeader *pUdpHeader, ULONG udpLength)
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{
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pUdpHeader->udp_xsum = CheckSumCalculator(0, pUdpHeader, udpLength);
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}
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/*********************************************
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Calculates TCP checksum, assuming the checksum field
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is initialized with pseudoheader checksum
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**********************************************/
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static __inline VOID CalculateTcpChecksumGivenPseudoCS(TCPHeader *pTcpHeader, ULONG tcpLength)
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{
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pTcpHeader->tcp_xsum = CheckSumCalculator(0, pTcpHeader, tcpLength);
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}
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/************************************************
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Checks (and fix if required) the TCP checksum
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sets flags in result structure according to verification
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TcpPseudoOK if valid pseudo CS was found
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TcpOK if valid TCP checksum was found
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************************************************/
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static __inline tTcpIpPacketParsingResult
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VerifyTcpChecksum( IPHeader *pIpHeader, ULONG len, tTcpIpPacketParsingResult known, ULONG whatToFix)
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{
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USHORT phcs;
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tTcpIpPacketParsingResult res = known;
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TCPHeader *pTcpHeader = (TCPHeader *)RtlOffsetToPointer(pIpHeader, res.ipHeaderSize);
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USHORT saved = pTcpHeader->tcp_xsum;
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USHORT xxpHeaderAndPayloadLen = GetXxpHeaderAndPayloadLen(pIpHeader, res);
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if (len >= res.ipHeaderSize)
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{
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phcs = CalculateIpPseudoHeaderChecksum(pIpHeader, res, xxpHeaderAndPayloadLen);
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res.xxpCheckSum = CompareNetCheckSumOnEndSystem(phcs, saved) ? ppresPCSOK : ppresCSBad;
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if (res.xxpCheckSum != ppresPCSOK || whatToFix)
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{
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if (whatToFix & pcrFixPHChecksum)
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{
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if (len >= (ULONG)(res.ipHeaderSize + sizeof(*pTcpHeader)))
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{
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pTcpHeader->tcp_xsum = phcs;
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res.fixedXxpCS = res.xxpCheckSum != ppresPCSOK;
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}
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else
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res.xxpStatus = ppresXxpIncomplete;
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}
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else if (res.xxpFull)
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{
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//USHORT ipFullLength = swap_short(pIpHeader->v4.ip_length);
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pTcpHeader->tcp_xsum = phcs;
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CalculateTcpChecksumGivenPseudoCS(pTcpHeader, xxpHeaderAndPayloadLen);
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if (CompareNetCheckSumOnEndSystem(pTcpHeader->tcp_xsum, saved))
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res.xxpCheckSum = ppresCSOK;
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if (!(whatToFix & pcrFixXxpChecksum))
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pTcpHeader->tcp_xsum = saved;
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else
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res.fixedXxpCS =
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res.xxpCheckSum == ppresCSBad || res.xxpCheckSum == ppresPCSOK;
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}
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else if (whatToFix)
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{
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res.xxpStatus = ppresXxpIncomplete;
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}
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}
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else if (res.xxpFull)
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{
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// we have correct PHCS and we do not need to fix anything
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// there is a very small chance that it is also good TCP CS
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// in such rare case we give a priority to TCP CS
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CalculateTcpChecksumGivenPseudoCS(pTcpHeader, xxpHeaderAndPayloadLen);
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if (CompareNetCheckSumOnEndSystem(pTcpHeader->tcp_xsum, saved))
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res.xxpCheckSum = ppresCSOK;
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pTcpHeader->tcp_xsum = saved;
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}
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}
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else
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res.ipCheckSum = ppresIPTooShort;
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return res;
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}
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/************************************************
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Checks (and fix if required) the UDP checksum
|
|
sets flags in result structure according to verification
|
|
UdpPseudoOK if valid pseudo CS was found
|
|
UdpOK if valid UDP checksum was found
|
|
************************************************/
|
|
static __inline tTcpIpPacketParsingResult
|
|
VerifyUdpChecksum( IPHeader *pIpHeader, ULONG len, tTcpIpPacketParsingResult known, ULONG whatToFix)
|
|
{
|
|
USHORT phcs;
|
|
tTcpIpPacketParsingResult res = known;
|
|
UDPHeader *pUdpHeader = (UDPHeader *)RtlOffsetToPointer(pIpHeader, res.ipHeaderSize);
|
|
USHORT saved = pUdpHeader->udp_xsum;
|
|
USHORT xxpHeaderAndPayloadLen = GetXxpHeaderAndPayloadLen(pIpHeader, res);
|
|
if (len >= res.ipHeaderSize)
|
|
{
|
|
phcs = CalculateIpPseudoHeaderChecksum(pIpHeader, res, xxpHeaderAndPayloadLen);
|
|
res.xxpCheckSum = CompareNetCheckSumOnEndSystem(phcs, saved) ? ppresPCSOK : ppresCSBad;
|
|
if (whatToFix & pcrFixPHChecksum)
|
|
{
|
|
if (len >= (ULONG)(res.ipHeaderSize + sizeof(UDPHeader)))
|
|
{
|
|
pUdpHeader->udp_xsum = phcs;
|
|
res.fixedXxpCS = res.xxpCheckSum != ppresPCSOK;
|
|
}
|
|
else
|
|
res.xxpStatus = ppresXxpIncomplete;
|
|
}
|
|
else if (res.xxpCheckSum != ppresPCSOK || (whatToFix & pcrFixXxpChecksum))
|
|
{
|
|
if (res.xxpFull)
|
|
{
|
|
pUdpHeader->udp_xsum = phcs;
|
|
CalculateUdpChecksumGivenPseudoCS(pUdpHeader, xxpHeaderAndPayloadLen);
|
|
if (CompareNetCheckSumOnEndSystem(pUdpHeader->udp_xsum, saved))
|
|
res.xxpCheckSum = ppresCSOK;
|
|
|
|
if (!(whatToFix & pcrFixXxpChecksum))
|
|
pUdpHeader->udp_xsum = saved;
|
|
else
|
|
res.fixedXxpCS =
|
|
res.xxpCheckSum == ppresCSBad || res.xxpCheckSum == ppresPCSOK;
|
|
}
|
|
else
|
|
res.xxpCheckSum = ppresXxpIncomplete;
|
|
}
|
|
else if (res.xxpFull)
|
|
{
|
|
// we have correct PHCS and we do not need to fix anything
|
|
// there is a very small chance that it is also good UDP CS
|
|
// in such rare case we give a priority to UDP CS
|
|
CalculateUdpChecksumGivenPseudoCS(pUdpHeader, xxpHeaderAndPayloadLen);
|
|
if (CompareNetCheckSumOnEndSystem(pUdpHeader->udp_xsum, saved))
|
|
res.xxpCheckSum = ppresCSOK;
|
|
pUdpHeader->udp_xsum = saved;
|
|
}
|
|
}
|
|
else
|
|
res.ipCheckSum = ppresIPTooShort;
|
|
|
|
return res;
|
|
}
|
|
|
|
static LPCSTR __inline GetPacketCase(tTcpIpPacketParsingResult res)
|
|
{
|
|
static const char *const IPCaseName[4] = { "not tested", "Non-IP", "IPv4", "IPv6" };
|
|
if (res.xxpStatus == ppresXxpKnown) return res.TcpUdp == ppresIsTCP ?
|
|
(res.ipStatus == ppresIPV4 ? "TCPv4" : "TCPv6") :
|
|
(res.ipStatus == ppresIPV4 ? "UDPv4" : "UDPv6");
|
|
if (res.xxpStatus == ppresXxpIncomplete) return res.TcpUdp == ppresIsTCP ? "Incomplete TCP" : "Incomplete UDP";
|
|
if (res.xxpStatus == ppresXxpOther) return "IP";
|
|
return IPCaseName[res.ipStatus];
|
|
}
|
|
|
|
static LPCSTR __inline GetIPCSCase(tTcpIpPacketParsingResult res)
|
|
{
|
|
static const char *const CSCaseName[4] = { "not tested", "(too short)", "OK", "Bad" };
|
|
return CSCaseName[res.ipCheckSum];
|
|
}
|
|
|
|
static LPCSTR __inline GetXxpCSCase(tTcpIpPacketParsingResult res)
|
|
{
|
|
static const char *const CSCaseName[4] = { "-", "PCS", "CS", "Bad" };
|
|
return CSCaseName[res.xxpCheckSum];
|
|
}
|
|
|
|
static __inline VOID PrintOutParsingResult(
|
|
tTcpIpPacketParsingResult res,
|
|
int level,
|
|
LPCSTR procname)
|
|
{
|
|
DPrintf(level, ("[%s] %s packet IPCS %s%s, checksum %s%s", procname,
|
|
GetPacketCase(res),
|
|
GetIPCSCase(res),
|
|
res.fixedIpCS ? "(fixed)" : "",
|
|
GetXxpCSCase(res),
|
|
res.fixedXxpCS ? "(fixed)" : ""));
|
|
}
|
|
|
|
tTcpIpPacketParsingResult ParaNdis_CheckSumVerify(PVOID buffer, ULONG size, ULONG flags, LPCSTR caller)
|
|
{
|
|
tTcpIpPacketParsingResult res = QualifyIpPacket(buffer, size);
|
|
if (res.ipStatus == ppresIPV4)
|
|
{
|
|
if (flags & pcrIpChecksum)
|
|
res = VerifyIpChecksum(buffer, res, (flags & pcrFixIPChecksum) != 0);
|
|
if(res.xxpStatus == ppresXxpKnown)
|
|
{
|
|
if (res.TcpUdp == ppresIsTCP) /* TCP */
|
|
{
|
|
if(flags & pcrTcpV4Checksum)
|
|
{
|
|
res = VerifyTcpChecksum(buffer, size, res, flags & (pcrFixPHChecksum | pcrFixTcpV4Checksum));
|
|
}
|
|
}
|
|
else /* UDP */
|
|
{
|
|
if (flags & pcrUdpV4Checksum)
|
|
{
|
|
res = VerifyUdpChecksum(buffer, size, res, flags & (pcrFixPHChecksum | pcrFixUdpV4Checksum));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
else if (res.ipStatus == ppresIPV6)
|
|
{
|
|
if(res.xxpStatus == ppresXxpKnown)
|
|
{
|
|
if (res.TcpUdp == ppresIsTCP) /* TCP */
|
|
{
|
|
if(flags & pcrTcpV6Checksum)
|
|
{
|
|
res = VerifyTcpChecksum(buffer, size, res, flags & (pcrFixPHChecksum | pcrFixTcpV6Checksum));
|
|
}
|
|
}
|
|
else /* UDP */
|
|
{
|
|
if (flags & pcrUdpV6Checksum)
|
|
{
|
|
res = VerifyUdpChecksum(buffer, size, res, flags & (pcrFixPHChecksum | pcrFixUdpV6Checksum));
|
|
}
|
|
}
|
|
}
|
|
}
|
|
PrintOutParsingResult(res, 1, caller);
|
|
return res;
|
|
}
|
|
|
|
tTcpIpPacketParsingResult ParaNdis_ReviewIPPacket(PVOID buffer, ULONG size, LPCSTR caller)
|
|
{
|
|
tTcpIpPacketParsingResult res = QualifyIpPacket(buffer, size);
|
|
PrintOutParsingResult(res, 1, caller);
|
|
return res;
|
|
}
|