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

   1 /*
   2  * COPYRIGHT:   See COPYING in the top level directory
   3  * PROJECT:     ReactOS TCP/IP protocol driver
   4  * FILE:        datalink/arp.c
   5  * PURPOSE:     Address Resolution 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 PNDIS_PACKET PrepareARPPacket(
  14     USHORT HardwareType,
  15     USHORT ProtocolType,
  16     UCHAR LinkAddressLength,
  17     UCHAR ProtoAddressLength,
  18     PVOID SenderLinkAddress,
  19     PVOID SenderProtoAddress,
  20     PVOID TargetLinkAddress,
  21     PVOID TargetProtoAddress,
  22     USHORT Opcode)
  23 /*
  24  * FUNCTION: Prepares an ARP packet
  25  * ARGUMENTS:
  26  *     HardwareType       = Hardware type (in network byte order)
  27  *     ProtocolType       = Protocol type (in network byte order)
  28  *     LinkAddressLength  = Length of link address fields
  29  *     ProtoAddressLength = Length of protocol address fields
  30  *     SenderLinkAddress  = Sender's link address
  31  *     SenderProtoAddress = Sender's protocol address
  32  *     TargetLinkAddress  = Target's link address (NULL if don't care)
  33  *     TargetProtoAddress = Target's protocol address
  34  *     Opcode             = ARP opcode (in network byte order)
  35  * RETURNS:
  36  *     Pointer to NDIS packet, NULL if there is not enough free resources
  37  */
  38 {
  39     PNDIS_PACKET NdisPacket;
  40     NDIS_STATUS NdisStatus;
  41     PARP_HEADER Header;
  42     PVOID DataBuffer;
  43     ULONG Size, Contig;
  44
  45     TI_DbgPrint(DEBUG_ARP, ("Called.\n"));
  46
  47     /* Prepare ARP packet */
  48     Size = MaxLLHeaderSize +
  49         sizeof(ARP_HEADER) +
  50         2 * LinkAddressLength + /* Hardware address length */
  51         2 * ProtoAddressLength; /* Protocol address length */
  52     Size = MAX(Size, MinLLFrameSize);
  53
  54     NdisStatus = AllocatePacketWithBuffer( &NdisPacket, NULL, Size );
  55     if( !NT_SUCCESS(NdisStatus) ) return NULL;
  56
  57     GetDataPtr( NdisPacket, 0, (PCHAR *)&DataBuffer, (PUINT)&Contig );
  58     ASSERT(DataBuffer);
  59
  60     RtlZeroMemory(DataBuffer, Size);
  61     Header = (PARP_HEADER)((ULONG_PTR)DataBuffer + MaxLLHeaderSize);
  62     Header->HWType       = HardwareType;
  63     Header->ProtoType    = ProtocolType;
  64     Header->HWAddrLen    = LinkAddressLength;
  65     Header->ProtoAddrLen = ProtoAddressLength;
  66     Header->Opcode       = Opcode; /* Already swapped */
  67     DataBuffer = (PVOID)((ULONG_PTR)Header + sizeof(ARP_HEADER));
  68
  69     /* Our hardware address */
  70     RtlCopyMemory(DataBuffer, SenderLinkAddress, LinkAddressLength);
  71     DataBuffer = (PVOID)((ULONG_PTR)DataBuffer + LinkAddressLength);
  72
  73     /* Our protocol address */
  74     RtlCopyMemory(DataBuffer, SenderProtoAddress, ProtoAddressLength);
  75
  76     if (TargetLinkAddress) {
  77         DataBuffer = (PVOID)((ULONG_PTR)DataBuffer + ProtoAddressLength);
  78         /* Target hardware address */
  79         RtlCopyMemory(DataBuffer, TargetLinkAddress, LinkAddressLength);
  80         DataBuffer = (PVOID)((ULONG_PTR)DataBuffer + LinkAddressLength);
  81     } else
  82         /* Don't care about target hardware address */
  83         DataBuffer = (PVOID)((ULONG_PTR)DataBuffer + ProtoAddressLength + LinkAddressLength);
  84
  85     /* Target protocol address */
  86     RtlCopyMemory(DataBuffer, TargetProtoAddress, ProtoAddressLength);
  87
  88     return NdisPacket;
  89 }
  90
  91
  92 VOID ARPTransmitComplete(
  93     PVOID Context,
  94     PNDIS_PACKET NdisPacket,
  95     NDIS_STATUS NdisStatus)
  96 /*
  97  * FUNCTION: ARP request transmit completion handler
  98  * ARGUMENTS:
  99  *     Context    = Pointer to context information (IP_INTERFACE)
 100  *     Packet     = Pointer to NDIS packet that was sent
 101  *     NdisStatus = NDIS status of operation
 102  * NOTES:
 103  *    This routine is called when an ARP request has been sent
 104  */
 105 {
 106     TI_DbgPrint(DEBUG_ARP, ("Called.\n"));
 107     FreeNdisPacket(NdisPacket);
 108 }
 109
 110
 111 BOOLEAN ARPTransmit(PIP_ADDRESS Address, PIP_INTERFACE Interface)
 112 /*
 113  * FUNCTION: Creates an ARP request and transmits it on a network
 114  * ARGUMENTS:
 115  *     Address = Pointer to IP address to resolve
 116  * RETURNS:
 117  *     TRUE if the request was successfully sent, FALSE if not
 118  */
 119 {
 120     PNDIS_PACKET NdisPacket;
 121     UCHAR ProtoAddrLen;
 122     USHORT ProtoType;
 123
 124     TI_DbgPrint(DEBUG_ARP, ("Called.\n"));
 125
 126     /* If Address is NULL then the caller wants an
 127      * gratuitous ARP packet sent */
 128     if (!Address)
 129         Address = &Interface->Unicast;
 130
 131     switch (Address->Type) {
 132         case IP_ADDRESS_V4:
 133             ProtoType    = (USHORT)ETYPE_IPv4; /* IPv4 */
 134             ProtoAddrLen = 4;                  /* Length of IPv4 address */
 135             break;
 136         case IP_ADDRESS_V6:
 137             ProtoType    = (USHORT)ETYPE_IPv6; /* IPv6 */
 138             ProtoAddrLen = 16;                 /* Length of IPv6 address */
 139             break;
 140         default:
 141             TI_DbgPrint(DEBUG_ARP,("Bad Address Type %x\n", Address->Type));
 142             KeBugCheck(0);
 143             /* Should not happen */
 144             return FALSE;
 145     }
 146
 147     NdisPacket = PrepareARPPacket(
 148         WN2H(0x0001),                    /* FIXME: Ethernet only */
 149         ProtoType,                       /* Protocol type */
 150         (UCHAR)Interface->AddressLength, /* Hardware address length */
 151         (UCHAR)ProtoAddrLen,             /* Protocol address length */
 152         Interface->Address,              /* Sender's (local) hardware address */
 153         &Interface->Unicast.Address.IPv4Address,/* Sender's (local) protocol address */
 154         NULL,                            /* Don't care */
 155         &Address->Address.IPv4Address,   /* Target's (remote) protocol address */
 156         ARP_OPCODE_REQUEST);             /* ARP request */
 157
 158     if( !NdisPacket ) return FALSE;
 159
 160     ASSERT_KM_POINTER(NdisPacket);
 161     ASSERT_KM_POINTER(PC(NdisPacket));
 162     PC(NdisPacket)->DLComplete = ARPTransmitComplete;
 163
 164     TI_DbgPrint(DEBUG_ARP,("Sending ARP Packet\n"));
 165
 166     (*Interface->Transmit)(Interface->Context, NdisPacket,
 167         MaxLLHeaderSize, NULL, LAN_PROTO_ARP);
 168
 169     return TRUE;
 170 }
 171
 172
 173 VOID ARPReceive(
 174     PVOID Context,
 175     PIP_PACKET Packet)
 176 /*
 177  * FUNCTION: Receives an ARP packet
 178  * ARGUMENTS:
 179  *     Context = Pointer to context information (IP_INTERFACE)
 180  *     Packet  = Pointer to packet
 181  */
 182 {
 183     PARP_HEADER Header;
 184     IP_ADDRESS Address;
 185     PVOID SenderHWAddress;
 186     PVOID SenderProtoAddress;
 187     PNEIGHBOR_CACHE_ENTRY NCE;
 188     PNDIS_PACKET NdisPacket;
 189     PIP_INTERFACE Interface = (PIP_INTERFACE)Context;
 190
 191     TI_DbgPrint(DEBUG_ARP, ("Called.\n"));
 192
 193     Header = (PARP_HEADER)Packet->Header;
 194
 195     /* FIXME: Ethernet only */
 196     if (WN2H(Header->HWType) != 1) {
 197         TI_DbgPrint(DEBUG_ARP, ("Unknown ARP hardware type (0x%X).\n", WN2H(Header->HWType)));
 198         return;
 199     }
 200
 201     /* Check protocol type */
 202     if (Header->ProtoType != ETYPE_IPv4) {
 203         TI_DbgPrint(DEBUG_ARP, ("Unknown ARP protocol type (0x%X).\n", WN2H(Header->ProtoType)));
 204         return;
 205     }
 206
 207     SenderHWAddress    = (PVOID)((ULONG_PTR)Header + sizeof(ARP_HEADER));
 208     SenderProtoAddress = (PVOID)((ULONG_PTR)SenderHWAddress + Header->HWAddrLen);
 209
 210     /* Check if we know the sender */
 211
 212     AddrInitIPv4(&Address, *((PULONG)SenderProtoAddress));
 213
 214     NCE = NBLocateNeighbor(&Address);
 215     if (NCE) {
 216         /* We know the sender. Update the hardware address
 217            and state in our neighbor address cache */
 218         NBUpdateNeighbor(NCE, SenderHWAddress, 0);
 219     } else {
 220         /* The packet had our protocol address as target. The sender
 221            may want to communicate with us soon, so add his address
 222            to our address cache */
 223         NCE = NBAddNeighbor(Interface, &Address, SenderHWAddress,
 224             Header->HWAddrLen, 0, ARP_TIMEOUT);
 225     }
 226
 227     if (Header->Opcode != ARP_OPCODE_REQUEST)
 228         return;
 229
 230     /* This is a request for our address. Swap the addresses and
 231        send an ARP reply back to the sender */
 232     NdisPacket = PrepareARPPacket(
 233         Header->HWType,                  /* Hardware type */
 234         Header->ProtoType,               /* Protocol type */
 235         (UCHAR)Interface->AddressLength, /* Hardware address length */
 236         (UCHAR)Header->ProtoAddrLen,     /* Protocol address length */
 237         Interface->Address,              /* Sender's (local) hardware address */
 238         &Interface->Unicast.Address.IPv4Address,/* Sender's (local) protocol address */
 239         SenderHWAddress,                 /* Target's (remote) hardware address */
 240         SenderProtoAddress,              /* Target's (remote) protocol address */
 241         ARP_OPCODE_REPLY);               /* ARP reply */
 242     if (NdisPacket) {
 243         PC(NdisPacket)->DLComplete = ARPTransmitComplete;
 244         (*Interface->Transmit)(Interface->Context,
 245                                NdisPacket,
 246                                MaxLLHeaderSize,
 247                                SenderHWAddress,
 248                                LAN_PROTO_ARP);
 249     }
 250
 251     Packet->Free(Packet);
 252 }
 253
 254 /* EOF */