/**

 * WinPR: Windows Portable Runtime

 * WinPR Logger

 *

 * Copyright 2013 Marc-Andre Moreau <marcandre.moreau@gmail.com>

 * Copyright 2015 Thincast Technologies GmbH

 * Copyright 2015 DI (FH) Martin Haimberger <martin.haimberger@thincast.com>

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <winpr/config.h>

#include "wlog.h"

#include "PacketMessage.h"

#include <winpr/wtypes.h>

#include <winpr/crt.h>

#include <winpr/file.h>

#include <winpr/stream.h>

#include <winpr/sysinfo.h>

#include "../../log.h"

#define TAG WINPR_TAG("utils.wlog")

static BOOL Pcap_Read_Header(wPcap* pcap, wPcapHeader* header)

{

  if (pcap && pcap->fp && fread((void*)header, sizeof(wPcapHeader), 1, pcap->fp) == 1)

    return TRUE;

  return FALSE;

}

static BOOL Pcap_Write_Header(wPcap* pcap, wPcapHeader* header)

{

  if (pcap && pcap->fp && fwrite((void*)header, sizeof(wPcapHeader), 1, pcap->fp) == 1)

    return TRUE;

  return FALSE;

}

static BOOL Pcap_Write_RecordHeader(wPcap* pcap, wPcapRecordHeader* record)

{

  if (pcap && pcap->fp && fwrite((void*)record, sizeof(wPcapRecordHeader), 1, pcap->fp) == 1)

    return TRUE;

  return FALSE;

}

static BOOL Pcap_Write_RecordContent(wPcap* pcap, wPcapRecord* record)

{

  if (pcap && pcap->fp && fwrite(record->data, record->length, 1, pcap->fp) == 1)

    return TRUE;

  return FALSE;

}

static BOOL Pcap_Write_Record(wPcap* pcap, wPcapRecord* record)

{

  return Pcap_Write_RecordHeader(pcap, &record->header) && Pcap_Write_RecordContent(pcap, record);

}

wPcap* Pcap_Open(char* name, BOOL write)

{

  wPcap* pcap = NULL;

  FILE* pcap_fp = winpr_fopen(name, write ? "w+b" : "rb");

  if (!pcap_fp)

  {

    WLog_ERR(TAG, "opening pcap file");

    return NULL;

  }

  pcap = (wPcap*)calloc(1, sizeof(wPcap));

  if (!pcap)

    goto out_fail;

  pcap->name = name;

  pcap->write = write;

  pcap->record_count = 0;

  pcap->fp = pcap_fp;

  if (write)

  {

    pcap->header.magic_number = PCAP_MAGIC_NUMBER;

    pcap->header.version_major = 2;

    pcap->header.version_minor = 4;

    pcap->header.thiszone = 0;

    pcap->header.sigfigs = 0;

    pcap->header.snaplen = 0xFFFFFFFF;

    pcap->header.network = 1; /* ethernet */

    if (!Pcap_Write_Header(pcap, &pcap->header))

      goto out_fail;

  }

  else

  {

    if (_fseeki64(pcap->fp, 0, SEEK_END) < 0)

      goto out_fail;

    pcap->file_size = (SSIZE_T)_ftelli64(pcap->fp);

    if (pcap->file_size < 0)

      goto out_fail;

    if (_fseeki64(pcap->fp, 0, SEEK_SET) < 0)

      goto out_fail;

    if (!Pcap_Read_Header(pcap, &pcap->header))

      goto out_fail;

  }

  return pcap;

out_fail:

  if (pcap_fp)

    (void)fclose(pcap_fp);

  free(pcap);

  return NULL;

}

void Pcap_Flush(wPcap* pcap)

{

  if (!pcap || !pcap->fp)

    return;

  while (pcap->record)

  {

    if (!Pcap_Write_Record(pcap, pcap->record))

      return;

    pcap->record = pcap->record->next;

  }

  (void)fflush(pcap->fp);

}

void Pcap_Close(wPcap* pcap)

{

  if (!pcap || !pcap->fp)

    return;

  Pcap_Flush(pcap);

  (void)fclose(pcap->fp);

  free(pcap);

}

static BOOL WLog_PacketMessage_Write_EthernetHeader(wPcap* pcap, wEthernetHeader* ethernet)

{

  wStream* s = NULL;

  wStream sbuffer = { 0 };

  BYTE buffer[14] = { 0 };

  BOOL ret = TRUE;

  if (!pcap || !pcap->fp || !ethernet)

    return FALSE;

  s = Stream_StaticInit(&sbuffer, buffer, sizeof(buffer));

  if (!s)

    return FALSE;

  Stream_Write(s, ethernet->Destination, 6);

  Stream_Write(s, ethernet->Source, 6);

  Stream_Write_UINT16_BE(s, ethernet->Type);

  if (fwrite(buffer, sizeof(buffer), 1, pcap->fp) != 1)

    ret = FALSE;

  return ret;

}

static UINT16 IPv4Checksum(const BYTE* ipv4, int length)

{

  long checksum = 0;

  while (length > 1)

  {

    const UINT16 tmp16 = *((const UINT16*)ipv4);

    checksum += tmp16;

    length -= 2;

    ipv4 += 2;

  }

  if (length > 0)

    checksum += *ipv4;

  while (checksum >> 16)

    checksum = (checksum & 0xFFFF) + (checksum >> 16);

  return (UINT16)(~checksum);

}

static BOOL WLog_PacketMessage_Write_IPv4Header(wPcap* pcap, wIPv4Header* ipv4)

{

  wStream* s = NULL;

  wStream sbuffer = { 0 };

  BYTE buffer[20] = { 0 };

  int ret = TRUE;

  if (!pcap || !pcap->fp || !ipv4)

    return FALSE;

  s = Stream_StaticInit(&sbuffer, buffer, sizeof(buffer));

  if (!s)

    return FALSE;

  Stream_Write_UINT8(s, (BYTE)((ipv4->Version << 4) | ipv4->InternetHeaderLength));

  Stream_Write_UINT8(s, ipv4->TypeOfService);

  Stream_Write_UINT16_BE(s, ipv4->TotalLength);

  Stream_Write_UINT16_BE(s, ipv4->Identification);

  Stream_Write_UINT16_BE(s, (UINT16)((ipv4->InternetProtocolFlags << 13) | ipv4->FragmentOffset));

  Stream_Write_UINT8(s, ipv4->TimeToLive);

  Stream_Write_UINT8(s, ipv4->Protocol);

  Stream_Write_UINT16(s, ipv4->HeaderChecksum);

  Stream_Write_UINT32_BE(s, ipv4->SourceAddress);

  Stream_Write_UINT32_BE(s, ipv4->DestinationAddress);

  ipv4->HeaderChecksum = IPv4Checksum((BYTE*)buffer, 20);

  Stream_Rewind(s, 10);

  Stream_Write_UINT16(s, ipv4->HeaderChecksum);

  if (fwrite(buffer, sizeof(buffer), 1, pcap->fp) != 1)

    ret = FALSE;

  return ret;

}

static BOOL WLog_PacketMessage_Write_TcpHeader(wPcap* pcap, wTcpHeader* tcp)

{

  wStream* s = NULL;

  wStream sbuffer = { 0 };

  BYTE buffer[20] = { 0 };

  BOOL ret = TRUE;

  if (!pcap || !pcap->fp || !tcp)

    return FALSE;

  s = Stream_StaticInit(&sbuffer, buffer, sizeof(buffer));

  if (!s)

    return FALSE;

  Stream_Write_UINT16_BE(s, tcp->SourcePort);

  Stream_Write_UINT16_BE(s, tcp->DestinationPort);

  Stream_Write_UINT32_BE(s, tcp->SequenceNumber);

  Stream_Write_UINT32_BE(s, tcp->AcknowledgementNumber);

  Stream_Write_UINT8(s, (UINT8)((tcp->Offset << 4) | (tcp->Reserved & 0xF)));

  Stream_Write_UINT8(s, tcp->TcpFlags);

  Stream_Write_UINT16_BE(s, tcp->Window);

  Stream_Write_UINT16_BE(s, tcp->Checksum);

  Stream_Write_UINT16_BE(s, tcp->UrgentPointer);

  if (pcap->fp)

  {

    if (fwrite(buffer, sizeof(buffer), 1, pcap->fp) != 1)

      ret = FALSE;

  }

  return ret;

}

static UINT32 g_InboundSequenceNumber = 0;

static UINT32 g_OutboundSequenceNumber = 0;

BOOL WLog_PacketMessage_Write(wPcap* pcap, void* data, size_t length, DWORD flags)

{

  wTcpHeader tcp;

  wIPv4Header ipv4;

  wPcapRecord record;

  wEthernetHeader ethernet;

  ethernet.Type = 0x0800;

  if (!pcap || !pcap->fp)

    return FALSE;

  if (flags & WLOG_PACKET_OUTBOUND)

  {

    /* 00:15:5D:01:64:04 */

    ethernet.Source[0] = 0x00;

    ethernet.Source[1] = 0x15;

    ethernet.Source[2] = 0x5D;

    ethernet.Source[3] = 0x01;

    ethernet.Source[4] = 0x64;

    ethernet.Source[5] = 0x04;

    /* 00:15:5D:01:64:01 */

    ethernet.Destination[0] = 0x00;

    ethernet.Destination[1] = 0x15;

    ethernet.Destination[2] = 0x5D;

    ethernet.Destination[3] = 0x01;

    ethernet.Destination[4] = 0x64;

    ethernet.Destination[5] = 0x01;

  }

  else

  {

    /* 00:15:5D:01:64:01 */

    ethernet.Source[0] = 0x00;

    ethernet.Source[1] = 0x15;

    ethernet.Source[2] = 0x5D;

    ethernet.Source[3] = 0x01;

    ethernet.Source[4] = 0x64;

    ethernet.Source[5] = 0x01;

    /* 00:15:5D:01:64:04 */

    ethernet.Destination[0] = 0x00;

    ethernet.Destination[1] = 0x15;

    ethernet.Destination[2] = 0x5D;

    ethernet.Destination[3] = 0x01;

    ethernet.Destination[4] = 0x64;

    ethernet.Destination[5] = 0x04;

  }

  ipv4.Version = 4;

  ipv4.InternetHeaderLength = 5;

  ipv4.TypeOfService = 0;

  ipv4.TotalLength = (UINT16)(length + 20 + 20);

  ipv4.Identification = 0;

  ipv4.InternetProtocolFlags = 0x02;

  ipv4.FragmentOffset = 0;

  ipv4.TimeToLive = 128;

  ipv4.Protocol = 6; /* TCP */

  ipv4.HeaderChecksum = 0;

  if (flags & WLOG_PACKET_OUTBOUND)

  {

    ipv4.SourceAddress = 0xC0A80196;      /* 192.168.1.150 */

    ipv4.DestinationAddress = 0x4A7D64C8; /* 74.125.100.200 */

  }

  else

  {

    ipv4.SourceAddress = 0x4A7D64C8;      /* 74.125.100.200 */

    ipv4.DestinationAddress = 0xC0A80196; /* 192.168.1.150 */

  }

  tcp.SourcePort = 3389;

  tcp.DestinationPort = 3389;

  if (flags & WLOG_PACKET_OUTBOUND)

  {

    tcp.SequenceNumber = g_OutboundSequenceNumber;

    tcp.AcknowledgementNumber = g_InboundSequenceNumber;

    WINPR_ASSERT(length + g_OutboundSequenceNumber <= UINT32_MAX);

    g_OutboundSequenceNumber += WINPR_ASSERTING_INT_CAST(uint32_t, length);

  }

  else

  {

    tcp.SequenceNumber = g_InboundSequenceNumber;

    tcp.AcknowledgementNumber = g_OutboundSequenceNumber;

    WINPR_ASSERT(length + g_InboundSequenceNumber <= UINT32_MAX);

    g_InboundSequenceNumber += WINPR_ASSERTING_INT_CAST(uint32_t, length);

  }

  tcp.Offset = 5;

  tcp.Reserved = 0;

  tcp.TcpFlags = 0x0018;

  tcp.Window = 0x7FFF;

  tcp.Checksum = 0;

  tcp.UrgentPointer = 0;

  record.data = data;

  record.length = length;

  const size_t offset = 14 + 20 + 20;

  WINPR_ASSERT(record.length <= UINT32_MAX - offset);

  const uint32_t rloff = WINPR_ASSERTING_INT_CAST(uint32_t, record.length + offset);

  record.header.incl_len = rloff;

  record.header.orig_len = rloff;

  record.next = NULL;

  UINT64 ns = winpr_GetUnixTimeNS();

  record.header.ts_sec = (UINT32)WINPR_TIME_NS_TO_S(ns);

  record.header.ts_usec = WINPR_TIME_NS_REM_US(ns);

  if (!Pcap_Write_RecordHeader(pcap, &record.header) ||

      !WLog_PacketMessage_Write_EthernetHeader(pcap, &ethernet) ||

      !WLog_PacketMessage_Write_IPv4Header(pcap, &ipv4) ||

      !WLog_PacketMessage_Write_TcpHeader(pcap, &tcp) || !Pcap_Write_RecordContent(pcap, &record))

    return FALSE;

  (void)fflush(pcap->fp);

  return TRUE;

}