reactos/drivers/lib/ip/network/icmp.c

   1 /*
   2  * COPYRIGHT:   See COPYING in the top level directory
   3  * PROJECT:     ReactOS TCP/IP protocol driver
   4  * FILE:        network/icmp.c
   5  * PURPOSE:     Internet Control Message Protocol routines
   6  * PROGRAMMERS: Casper S. Hornstrup (chorns@users.sourceforge.net)
   7  * REVISIONS:
   8  *   CSH 01/08-2000 Created
   9  */
  10
  11 #include "precomp.h"
  12
  13
  14 VOID SendICMPComplete(
  15     PVOID Context,
  16     PNDIS_PACKET Packet,
  17     NDIS_STATUS NdisStatus)
  18 /*
  19  * FUNCTION: ICMP datagram transmit completion handler
  20  * ARGUMENTS:
  21  *     Context    = Pointer to context infomation (IP_PACKET)
  22  *     Packet     = Pointer to NDIS packet
  23  *     NdisStatus = Status of transmit operation
  24  * NOTES:
  25  *     This routine is called by IP when a ICMP send completes
  26  */
  27 {
  28     TI_DbgPrint(DEBUG_ICMP, ("Freeing NDIS packet (%X).\n", Packet));
  29
  30     /* Free packet */
  31     FreeNdisPacket(Packet);
  32
  33     TI_DbgPrint(DEBUG_ICMP, ("Done\n"));
  34 }
  35
  36
  37 PIP_PACKET PrepareICMPPacket(
  38     PIP_INTERFACE Interface,
  39     PIP_PACKET IPPacket,
  40     PIP_ADDRESS Destination,
  41     PCHAR Data,
  42     UINT DataSize)
  43 /*
  44  * FUNCTION: Prepares an ICMP packet
  45  * ARGUMENTS:
  46  *     NTE         = Pointer to net table entry to use
  47  *     Destination = Pointer to destination address
  48  *     DataSize    = Size of dataarea
  49  * RETURNS:
  50  *     Pointer to IP packet, NULL if there is not enough free resources
  51  */
  52 {
  53     PNDIS_PACKET NdisPacket;
  54     NDIS_STATUS NdisStatus;
  55     PIPv4_HEADER IPHeader;
  56     ULONG Size;
  57
  58     TI_DbgPrint(DEBUG_ICMP, ("Called. DataSize (%d).\n", DataSize));
  59
  60     /* No special flags */
  61     IPPacket->Flags = 0;
  62
  63     Size = MaxLLHeaderSize + sizeof(IPv4_HEADER) + DataSize;
  64
  65     /* Allocate NDIS packet */
  66     NdisStatus = AllocatePacketWithBuffer( &NdisPacket, NULL, Size );
  67
  68     if( !NT_SUCCESS(NdisStatus) ) return NULL;
  69
  70     IPPacket->NdisPacket = NdisPacket;
  71
  72     GetDataPtr( IPPacket->NdisPacket, MaxLLHeaderSize,
  73                 (PCHAR *)&IPPacket->Header, &IPPacket->ContigSize );
  74
  75     IPPacket->Data = ((PCHAR)IPPacket->Header) + IPPacket->HeaderSize;
  76
  77     TI_DbgPrint(DEBUG_ICMP, ("Size (%d). Data at (0x%X).\n", Size, Data));
  78     TI_DbgPrint(DEBUG_ICMP, ("NdisPacket at (0x%X).\n", NdisPacket));
  79
  80     IPPacket->HeaderSize = sizeof(IPv4_HEADER);
  81     IPPacket->TotalSize  = Size - MaxLLHeaderSize;
  82
  83     TI_DbgPrint(DEBUG_ICMP, ("Copying Address: %x -> %x\n",
  84                              &IPPacket->DstAddr, Destination));
  85
  86     RtlCopyMemory(&IPPacket->DstAddr, Destination, sizeof(IP_ADDRESS));
  87     RtlCopyMemory(IPPacket->Data, Data, DataSize);
  88
  89     /* Build IPv4 header. FIXME: IPv4 only */
  90
  91     IPHeader = (PIPv4_HEADER)IPPacket->Header;
  92
  93     /* Version = 4, Length = 5 DWORDs */
  94     IPHeader->VerIHL = 0x45;
  95     /* Normal Type-of-Service */
  96     IPHeader->Tos = 0;
  97     /* Length of data and header */
  98     IPHeader->TotalLength = WH2N((USHORT)DataSize + sizeof(IPv4_HEADER));
  99     /* Identification */
 100     IPHeader->Id = (USHORT)Random();
 101     /* One fragment at offset 0 */
 102     IPHeader->FlagsFragOfs = 0;
 103     /* Time-to-Live is 128 */
 104     IPHeader->Ttl = 128;
 105     /* Internet Control Message Protocol */
 106     IPHeader->Protocol = IPPROTO_ICMP;
 107     /* Checksum is 0 (for later calculation of this) */
 108     IPHeader->Checksum = 0;
 109     /* Source address */
 110     IPHeader->SrcAddr = Interface->Unicast.Address.IPv4Address;
 111     /* Destination address */
 112     IPHeader->DstAddr = Destination->Address.IPv4Address;
 113
 114
 115     TI_DbgPrint(MID_TRACE,("Leaving\n"));
 116
 117     return IPPacket;
 118 }
 119
 120
 121 VOID ICMPReceive(
 122     PIP_INTERFACE Interface,
 123     PIP_PACKET IPPacket)
 124 /*
 125  * FUNCTION: Receives an ICMP packet
 126  * ARGUMENTS:
 127  *     NTE      = Pointer to net table entry which the packet was received on
 128  *     IPPacket = Pointer to an IP packet that was received
 129  */
 130 {
 131     PICMP_HEADER ICMPHeader;
 132
 133     TI_DbgPrint(DEBUG_ICMP, ("Called.\n"));
 134
 135     ICMPHeader = (PICMP_HEADER)IPPacket->Data;
 136
 137     TI_DbgPrint(DEBUG_ICMP, ("Size (%d).\n", IPPacket->TotalSize));
 138
 139     TI_DbgPrint(DEBUG_ICMP, ("HeaderSize (%d).\n", IPPacket->HeaderSize));
 140
 141     TI_DbgPrint(DEBUG_ICMP, ("Type (%d).\n", ICMPHeader->Type));
 142
 143     TI_DbgPrint(DEBUG_ICMP, ("Code (%d).\n", ICMPHeader->Code));
 144
 145     TI_DbgPrint(DEBUG_ICMP, ("Checksum (0x%X).\n", ICMPHeader->Checksum));
 146
 147     /* Checksum ICMP header and data */
 148     if (!IPv4CorrectChecksum(IPPacket->Data, IPPacket->TotalSize - IPPacket->HeaderSize)) {
 149         TI_DbgPrint(DEBUG_ICMP, ("Bad ICMP checksum.\n"));
 150         /* Discard packet */
 151         return;
 152     }
 153
 154     switch (ICMPHeader->Type) {
 155     case ICMP_TYPE_ECHO_REQUEST:
 156         ICMPReply( Interface, IPPacket, ICMP_TYPE_ECHO_REPLY, 0 );
 157         return;
 158
 159     case ICMP_TYPE_ECHO_REPLY:
 160         break;
 161
 162     default:
 163         TI_DbgPrint(DEBUG_ICMP,
 164                     ("Discarded ICMP datagram of unknown type %d.\n",
 165                      ICMPHeader->Type));
 166         /* Discard packet */
 167         break;
 168     }
 169 }
 170
 171
 172 VOID ICMPTransmit(
 173     PIP_PACKET IPPacket,
 174     PIP_TRANSMIT_COMPLETE Complete,
 175     PVOID Context)
 176 /*
 177  * FUNCTION: Transmits an ICMP packet
 178  * ARGUMENTS:
 179  *     NTE      = Pointer to net table entry to use (NULL if don't care)
 180  *     IPPacket = Pointer to IP packet to transmit
 181  */
 182 {
 183     PNEIGHBOR_CACHE_ENTRY NCE;
 184
 185     TI_DbgPrint(DEBUG_ICMP, ("Called.\n"));
 186
 187     /* Calculate checksum of ICMP header and data */
 188     ((PICMP_HEADER)IPPacket->Data)->Checksum = (USHORT)
 189         IPv4Checksum(IPPacket->Data, IPPacket->TotalSize - IPPacket->HeaderSize, 0);
 190
 191     /* Get a route to the destination address */
 192     if ((NCE = RouteGetRouteToDestination(&IPPacket->DstAddr))) {
 193         /* Send the packet */
 194         IPSendDatagram(IPPacket, NCE, Complete, Context);
 195     } else {
 196         /* No route to destination (or no free resources) */
 197         TI_DbgPrint(DEBUG_ICMP, ("No route to destination address 0x%X.\n",
 198                                  IPPacket->DstAddr.Address.IPv4Address));
 199         /* Discard packet */
 200         Complete( Context, IPPacket->NdisPacket, NDIS_STATUS_NOT_ACCEPTED );
 201     }
 202 }
 203
 204
 205 VOID ICMPReply(
 206     PIP_INTERFACE Interface,
 207     PIP_PACKET IPPacket,
 208     UCHAR Type,
 209     UCHAR Code)
 210 /*
 211  * FUNCTION: Transmits an ICMP packet in response to an incoming packet
 212  * ARGUMENTS:
 213  *     NTE      = Pointer to net table entry to use
 214  *     IPPacket = Pointer to IP packet that was received
 215  *     Type     = ICMP message type
 216  *     Code     = ICMP message code
 217  * NOTES:
 218  *     We have received a packet from someone and is unable to
 219  *     process it due to error(s) in the packet or we have run out
 220  *     of resources. We transmit an ICMP message to the host to
 221  *     notify him of the problem
 222  */
 223 {
 224     UINT DataSize, PayloadSize;
 225     IP_PACKET NewPacket = *IPPacket;
 226
 227     TI_DbgPrint(DEBUG_ICMP, ("Called. Type (%d)  Code (%d).\n", Type, Code));
 228
 229     DataSize = IPPacket->TotalSize - IPPacket->HeaderSize;
 230     PayloadSize = DataSize - sizeof(ICMP_HEADER);
 231     if ((PayloadSize) > 576) {
 232         PayloadSize = 576;
 233         DataSize = PayloadSize + sizeof(ICMP_HEADER);
 234     }
 235
 236     if( !PrepareICMPPacket(Interface, &NewPacket, &IPPacket->SrcAddr,
 237                            IPPacket->Data, DataSize) ) return;
 238
 239     ((PICMP_HEADER)NewPacket.Data)->Type     = Type;
 240     ((PICMP_HEADER)NewPacket.Data)->Code     = Code;
 241     ((PICMP_HEADER)NewPacket.Data)->Checksum = 0;
 242
 243     ICMPTransmit(&NewPacket, SendICMPComplete, NULL);
 244 }
 245
 246 /* EOF */