2 * COPYRIGHT: See COPYING in the top level directory
3 * PROJECT: ReactOS TCP/IP protocol driver
5 * PURPOSE: Address Resolution Protocol routines
6 * PROGRAMMERS: Casper S. Hornstrup (chorns@users.sourceforge.net)
8 * CSH 01/08-2000 Created
13 PNDIS_PACKET
PrepareARPPacket(
17 UCHAR LinkAddressLength
,
18 UCHAR ProtoAddressLength
,
19 PVOID SenderLinkAddress
,
20 PVOID SenderProtoAddress
,
21 PVOID TargetLinkAddress
,
22 PVOID TargetProtoAddress
,
25 * FUNCTION: Prepares an ARP packet
27 * HardwareType = Hardware type (in network byte order)
28 * ProtocolType = Protocol type (in network byte order)
29 * LinkAddressLength = Length of link address fields
30 * ProtoAddressLength = Length of protocol address fields
31 * SenderLinkAddress = Sender's link address
32 * SenderProtoAddress = Sender's protocol address
33 * TargetLinkAddress = Target's link address (NULL if don't care)
34 * TargetProtoAddress = Target's protocol address
35 * Opcode = ARP opcode (in network byte order)
37 * Pointer to NDIS packet, NULL if there is not enough free resources
40 PNDIS_PACKET NdisPacket
;
41 NDIS_STATUS NdisStatus
;
46 TI_DbgPrint(DEBUG_ARP
, ("Called.\n"));
48 /* Prepare ARP packet */
49 Size
= sizeof(ARP_HEADER
) +
50 2 * LinkAddressLength
+ /* Hardware address length */
51 2 * ProtoAddressLength
; /* Protocol address length */
52 Size
= MAX(Size
, IF
->MinFrameSize
- IF
->HeaderSize
);
54 NdisStatus
= AllocatePacketWithBuffer( &NdisPacket
, NULL
, Size
);
55 if( !NT_SUCCESS(NdisStatus
) ) return NULL
;
57 GetDataPtr( NdisPacket
, 0, (PCHAR
*)&DataBuffer
, (PUINT
)&Contig
);
60 RtlZeroMemory(DataBuffer
, Size
);
61 Header
= (PARP_HEADER
)((ULONG_PTR
)DataBuffer
);
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
));
69 /* Our hardware address */
70 RtlCopyMemory(DataBuffer
, SenderLinkAddress
, LinkAddressLength
);
71 DataBuffer
= (PVOID
)((ULONG_PTR
)DataBuffer
+ LinkAddressLength
);
73 /* Our protocol address */
74 RtlCopyMemory(DataBuffer
, SenderProtoAddress
, ProtoAddressLength
);
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
);
82 /* Don't care about target hardware address */
83 DataBuffer
= (PVOID
)((ULONG_PTR
)DataBuffer
+ ProtoAddressLength
+ LinkAddressLength
);
85 /* Target protocol address */
86 RtlCopyMemory(DataBuffer
, TargetProtoAddress
, ProtoAddressLength
);
92 VOID
ARPTransmitComplete(
94 PNDIS_PACKET NdisPacket
,
95 NDIS_STATUS NdisStatus
)
97 * FUNCTION: ARP request transmit completion handler
99 * Context = Pointer to context information (IP_INTERFACE)
100 * Packet = Pointer to NDIS packet that was sent
101 * NdisStatus = NDIS status of operation
103 * This routine is called when an ARP request has been sent
106 TI_DbgPrint(DEBUG_ARP
, ("Called.\n"));
107 FreeNdisPacket(NdisPacket
);
111 BOOLEAN
ARPTransmit(PIP_ADDRESS Address
, PIP_INTERFACE Interface
)
113 * FUNCTION: Creates an ARP request and transmits it on a network
115 * Address = Pointer to IP address to resolve
117 * TRUE if the request was successfully sent, FALSE if not
120 PNDIS_PACKET NdisPacket
;
124 TI_DbgPrint(DEBUG_ARP
, ("Called.\n"));
126 /* If Address is NULL then the caller wants an
127 * gratuitous ARP packet sent */
129 Address
= &Interface
->Unicast
;
131 switch (Address
->Type
) {
133 ProtoType
= (USHORT
)ETYPE_IPv4
; /* IPv4 */
134 ProtoAddrLen
= 4; /* Length of IPv4 address */
137 ProtoType
= (USHORT
)ETYPE_IPv6
; /* IPv6 */
138 ProtoAddrLen
= 16; /* Length of IPv6 address */
141 TI_DbgPrint(DEBUG_ARP
,("Bad Address Type %x\n", Address
->Type
));
143 /* Should not happen */
147 NdisPacket
= PrepareARPPacket(
149 WN2H(0x0001), /* FIXME: Ethernet only */
150 ProtoType
, /* Protocol type */
151 (UCHAR
)Interface
->AddressLength
, /* Hardware address length */
152 (UCHAR
)ProtoAddrLen
, /* Protocol address length */
153 Interface
->Address
, /* Sender's (local) hardware address */
154 &Interface
->Unicast
.Address
.IPv4Address
,/* Sender's (local) protocol address */
155 NULL
, /* Don't care */
156 &Address
->Address
.IPv4Address
, /* Target's (remote) protocol address */
157 ARP_OPCODE_REQUEST
); /* ARP request */
159 if( !NdisPacket
) return FALSE
;
161 ASSERT_KM_POINTER(NdisPacket
);
162 ASSERT_KM_POINTER(PC(NdisPacket
));
163 PC(NdisPacket
)->DLComplete
= ARPTransmitComplete
;
165 TI_DbgPrint(DEBUG_ARP
,("Sending ARP Packet\n"));
167 (*Interface
->Transmit
)(Interface
->Context
, NdisPacket
,
168 0, NULL
, LAN_PROTO_ARP
);
178 * FUNCTION: Receives an ARP packet
180 * Context = Pointer to context information (IP_INTERFACE)
181 * Packet = Pointer to packet
186 PVOID SenderHWAddress
;
187 PVOID SenderProtoAddress
;
188 PNEIGHBOR_CACHE_ENTRY NCE
;
189 PNDIS_PACKET NdisPacket
;
190 PIP_INTERFACE Interface
= (PIP_INTERFACE
)Context
;
192 TI_DbgPrint(DEBUG_ARP
, ("Called.\n"));
194 Header
= (PARP_HEADER
)Packet
->Header
;
196 /* FIXME: Ethernet only */
197 if (WN2H(Header
->HWType
) != 1) {
198 TI_DbgPrint(DEBUG_ARP
, ("Unknown ARP hardware type (0x%X).\n", WN2H(Header
->HWType
)));
202 /* Check protocol type */
203 if (Header
->ProtoType
!= ETYPE_IPv4
) {
204 TI_DbgPrint(DEBUG_ARP
, ("Unknown ARP protocol type (0x%X).\n", WN2H(Header
->ProtoType
)));
208 SenderHWAddress
= (PVOID
)((ULONG_PTR
)Header
+ sizeof(ARP_HEADER
));
209 SenderProtoAddress
= (PVOID
)((ULONG_PTR
)SenderHWAddress
+ Header
->HWAddrLen
);
211 /* Check if we know the sender */
213 AddrInitIPv4(&Address
, *((PULONG
)SenderProtoAddress
));
215 NCE
= NBLocateNeighbor(&Address
);
217 /* We know the sender. Update the hardware address
218 and state in our neighbor address cache */
219 NBUpdateNeighbor(NCE
, SenderHWAddress
, 0);
221 /* The packet had our protocol address as target. The sender
222 may want to communicate with us soon, so add his address
223 to our address cache */
224 NCE
= NBAddNeighbor(Interface
, &Address
, SenderHWAddress
,
225 Header
->HWAddrLen
, 0, ARP_TIMEOUT
);
228 if (Header
->Opcode
!= ARP_OPCODE_REQUEST
)
231 /* This is a request for our address. Swap the addresses and
232 send an ARP reply back to the sender */
233 NdisPacket
= PrepareARPPacket(
235 Header
->HWType
, /* Hardware type */
236 Header
->ProtoType
, /* Protocol type */
237 (UCHAR
)Interface
->AddressLength
, /* Hardware address length */
238 (UCHAR
)Header
->ProtoAddrLen
, /* Protocol address length */
239 Interface
->Address
, /* Sender's (local) hardware address */
240 &Interface
->Unicast
.Address
.IPv4Address
,/* Sender's (local) protocol address */
241 SenderHWAddress
, /* Target's (remote) hardware address */
242 SenderProtoAddress
, /* Target's (remote) protocol address */
243 ARP_OPCODE_REPLY
); /* ARP reply */
245 PC(NdisPacket
)->DLComplete
= ARPTransmitComplete
;
246 (*Interface
->Transmit
)(Interface
->Context
,
253 Packet
->Free(Packet
);