2 Transmit the IP4 packet.
4 Copyright (c) 2005 - 2009, Intel Corporation. All rights reserved.<BR>
5 This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
21 Prepend an IP4 head to the Packet. It will copy the options and
22 build the IP4 header fields. Used for IP4 fragmentation.
24 @param Packet The packet to prepend IP4 header to
25 @param Head The caller supplied header. The caller should set
26 the following header fields: Tos, TotalLen, Id,
27 Fragment, Ttl, Protocol, Src and Dst. All the fields
28 are in host byte order. This function will fill in
29 the Ver, HeadLen, and checksum.
30 @param Option The orginal IP4 option to copy from
31 @param OptLen The length of the IP4 option
33 @retval EFI_BAD_BUFFER_SIZE There is no enought room in the head space of
35 @retval EFI_SUCCESS The IP4 header is successfully added to the packet.
40 IN OUT NET_BUF
*Packet
,
49 BOOLEAN FirstFragment
;
52 // Prepend the options: first get the option length, then copy it over.
55 FirstFragment
= IP4_FIRST_FRAGMENT (Head
->Fragment
);
57 Ip4CopyOption (Option
, OptLen
, FirstFragment
, NULL
, &Len
);
59 HeadLen
= IP4_MIN_HEADLEN
+ Len
;
60 ASSERT (((Len
% 4) == 0) && (HeadLen
<= IP4_MAX_HEADLEN
));
62 PacketHead
= (IP4_HEAD
*) NetbufAllocSpace (Packet
, HeadLen
, NET_BUF_HEAD
);
64 if (PacketHead
== NULL
) {
65 return EFI_BAD_BUFFER_SIZE
;
68 Ip4CopyOption (Option
, OptLen
, FirstFragment
, (UINT8
*) (PacketHead
+ 1), &Len
);
71 // Set the head up, convert the host byte order to network byte order
74 PacketHead
->HeadLen
= (UINT8
) (HeadLen
>> 2);
75 PacketHead
->Tos
= Head
->Tos
;
76 PacketHead
->TotalLen
= HTONS ((UINT16
) Packet
->TotalSize
);
77 PacketHead
->Id
= HTONS (Head
->Id
);
78 PacketHead
->Fragment
= HTONS (Head
->Fragment
);
79 PacketHead
->Checksum
= 0;
80 PacketHead
->Ttl
= Head
->Ttl
;
81 PacketHead
->Protocol
= Head
->Protocol
;
82 PacketHead
->Src
= HTONL (Head
->Src
);
83 PacketHead
->Dst
= HTONL (Head
->Dst
);
84 PacketHead
->Checksum
= (UINT16
) (~NetblockChecksum ((UINT8
*) PacketHead
, HeadLen
));
86 Packet
->Ip
.Ip4
= PacketHead
;
92 Select an interface to send the packet generated in the IP4 driver
93 itself, that is, not by the requests of IP4 child's consumer. Such
94 packets include the ICMP echo replies, and other ICMP error packets.
96 @param[in] IpSb The IP4 service that wants to send the packets.
97 @param[in] Dst The destination of the packet
98 @param[in] Src The source of the packet
100 @return NULL if no proper interface is found, otherwise the interface that
101 can be used to send the system packet from.
106 IN IP4_SERVICE
*IpSb
,
112 IP4_INTERFACE
*Selected
;
116 // Select the interface the Dst is on if one of the connected
117 // network. Some IP instance may be configured with 0.0.0.0/0,
118 // don't select that interface now.
120 IpIf
= Ip4FindNet (IpSb
, Dst
);
122 if ((IpIf
!= NULL
) && (IpIf
->Ip
!= IP4_ALLZERO_ADDRESS
)) {
127 // If source is one of the interface address, select it.
129 IpIf
= Ip4FindInterface (IpSb
, Src
);
131 if ((IpIf
!= NULL
) && (IpIf
->Ip
!= IP4_ALLZERO_ADDRESS
)) {
136 // Select a configured interface as the fall back. Always prefer
137 // an interface with non-zero address.
141 NET_LIST_FOR_EACH (Entry
, &IpSb
->Interfaces
) {
142 IpIf
= NET_LIST_USER_STRUCT (Entry
, IP4_INTERFACE
, Link
);
144 if (IpIf
->Configured
&& ((Selected
== NULL
) || (Selected
->Ip
== 0))) {
154 The default callback function for system generated packet.
155 It will free the packet.
157 @param Ip4Instance The IP4 child that issued the transmission. It most
159 @param Packet The packet that transmitted.
160 @param IoStatus The result of the transmission, succeeded or failed.
161 @param LinkFlag Not used when transmission. check IP4_FRAME_CALLBACK
163 @param Context The context provided by us
168 IP4_PROTOCOL
*Ip4Instance
,
180 Transmit an IP4 packet. The packet comes either from the IP4
181 child's consumer (IpInstance != NULL) or the IP4 driver itself
182 (IpInstance == NULL). It will route the packet, fragment it,
183 then transmit all the fragments through some interface.
185 @param[in] IpSb The IP4 service instance to transmit the packet
186 @param[in] IpInstance The IP4 child that issues the transmission. It is
187 NULL if the packet is from the system.
188 @param[in] Packet The user data to send, excluding the IP header.
189 @param[in] Head The caller supplied header. The caller should set
190 the following header fields: Tos, TotalLen, Id, tl,
191 Fragment, Protocol, Src and Dst. All the fields are
192 in host byte order. This function will fill in the
193 Ver, HeadLen, Fragment, and checksum. The Fragment
194 only need to include the DF flag. Ip4Output will
195 compute the MF and offset for you.
196 @param[in] Option The original option to append to the IP headers
197 @param[in] OptLen The length of the option
198 @param[in] GateWay The next hop address to transmit packet to.
199 255.255.255.255 means broadcast.
200 @param[in] Callback The callback function to issue when transmission
202 @param[in] Context The opaque context for the callback
204 @retval EFI_NO_MAPPING There is no interface to the destination.
205 @retval EFI_NOT_FOUND There is no route to the destination
206 @retval EFI_SUCCESS The packet is successfully transmitted.
207 @retval Others Failed to transmit the packet.
212 IN IP4_SERVICE
*IpSb
,
213 IN IP4_PROTOCOL
*IpInstance OPTIONAL
,
219 IN IP4_FRAME_CALLBACK Callback
,
224 IP4_ROUTE_CACHE_ENTRY
*CacheEntry
;
236 // Select an interface/source for system packet, application
237 // should select them itself.
239 if (IpInstance
== NULL
) {
240 IpIf
= Ip4SelectInterface (IpSb
, Head
->Dst
, Head
->Src
);
242 IpIf
= IpInstance
->Interface
;
246 return EFI_NO_MAPPING
;
249 if ((Head
->Src
== IP4_ALLZERO_ADDRESS
) && (IpInstance
== NULL
)) {
250 Head
->Src
= IpIf
->Ip
;
254 // Before IPsec process, prepared the IP head.
256 HeadLen
= sizeof (IP4_HEAD
) + ((OptLen
+ 3) & (~0x03));
257 Head
->HeadLen
= (UINT8
) (HeadLen
>> 2);
262 // Call IPsec process.
264 Status
= Ip4IpSecProcessPacket (
274 if (EFI_ERROR(Status
)) {
279 // Route the packet unless overrided, that is, GateWay isn't zero.
281 if (GateWay
== IP4_ALLZERO_ADDRESS
) {
284 if (IP4_IS_BROADCAST (Ip4GetNetCast (Dest
, IpIf
)) || (Dest
== IP4_ALLONE_ADDRESS
)) {
286 // Set the gateway to local broadcast if the Dest is
287 // the broadcast address for the connected network or
288 // it is local broadcast.
290 GateWay
= IP4_ALLONE_ADDRESS
;
292 } else if (IP4_IS_MULTICAST (Dest
)) {
294 // Set the gateway to the destination if it is an multicast
295 // address. The IP4_INTERFACE won't consult ARP to send local
296 // broadcast and multicast.
302 // Consult the route table to route the packet
304 if (IpInstance
== NULL
) {
305 CacheEntry
= Ip4Route (IpSb
->DefaultRouteTable
, Head
->Dst
, Head
->Src
);
307 CacheEntry
= Ip4Route (IpInstance
->RouteTable
, Head
->Dst
, Head
->Src
);
310 if (CacheEntry
== NULL
) {
311 return EFI_NOT_FOUND
;
314 GateWay
= CacheEntry
->NextHop
;
315 Ip4FreeRouteCacheEntry (CacheEntry
);
320 // OK, selected the source and route, fragment the packet then send
321 // them. Tag each fragment other than the first one as spawn from it.
323 Mtu
= IpSb
->MaxPacketSize
+ sizeof (IP4_HEAD
);
325 if (Packet
->TotalSize
+ HeadLen
> Mtu
) {
327 // Packet is fragmented from the tail to the head, that is, the
328 // first frame sent is the last fragment of the packet. The first
329 // fragment is NOT sent in this loop. First compute how many
330 // fragments there are.
332 Mtu
= (Mtu
- HeadLen
) & (~0x07);
333 Num
= (Packet
->TotalSize
+ Mtu
- 1) / Mtu
;
336 // Initialize the packet length and Offset. Other than the last
337 // fragment, the packet length equals to MTU. The offset is always
340 PacketLen
= Packet
->TotalSize
- (Num
- 1) * Mtu
;
341 Offset
= Mtu
* (Num
- 1);
343 for (Index
= 0; Index
< Num
- 1; Index
++, Offset
-= Mtu
) {
344 Fragment
= NetbufGetFragment (Packet
, Offset
, PacketLen
, IP4_MAX_HEADLEN
);
346 if (Fragment
== NULL
) {
347 Status
= EFI_OUT_OF_RESOURCES
;
352 // Update the header's fragment. The caller fills the IP4 header
353 // fields that are required by Ip4PrependHead except the fragment.
355 Head
->Fragment
= IP4_HEAD_FRAGMENT_FIELD (FALSE
, (Index
!= 0), Offset
);
356 Ip4PrependHead (Fragment
, Head
, Option
, OptLen
);
359 // Transmit the fragments, pass the Packet address as the context.
360 // So, we can find all the fragments spawned from the Packet by
361 // compare the NetBuf and Context to the Packet.
363 Status
= Ip4SendFrame (
372 if (EFI_ERROR (Status
)) {
380 // Trim the already sent data, then adjust the head's fragment field.
382 NetbufTrim (Packet
, Packet
->TotalSize
- Mtu
, FALSE
);
383 Head
->Fragment
= IP4_HEAD_FRAGMENT_FIELD (FALSE
, TRUE
, 0);
387 // Send the first fragment, it is either the orginal packet, or the
388 // first fragment of a fragmented packet. It seems that there is a subtle
389 // bug here: what if the caller free the packet in Callback and IpIf (or
390 // MNP child used by that interface) still holds the fragments and try
391 // to access the data? The caller can free the packet if it recycles the
392 // consumer's (such as UDP) data in the Callback. But this can't happen.
393 // The detailed sequence is:
394 // 1. for the packets generated by IP4 driver itself:
395 // The Callback is Ip4SysPacketSent, which is the same as the
396 // fragments' callback. Ip4SysPacketSent simply calls NetbufFree
397 // to release its reference to the packet. So, no problem for
400 // 2. for the upper layer's packets (use UDP as an example):
401 // UDP requests the IP layer to transmit some data which is
402 // wrapped in an asynchronous token, the token is wrapped
403 // in IP4_TXTOKEN_WRAP by IP4. IP4 also wrap the user's data
404 // in a net buffer, which is Packet we get here. IP4_TXTOKEN_WRAP
405 // is bound with the Packet. It will only be freed when all
406 // the references to Packet have been released. Upon then, the
407 // Packet's OnFree callback will release the IP4_TXTOKEN_WRAP,
408 // and singal the user's recycle event. So, also no problem for
409 // upper layer's packets.
411 Ip4PrependHead (Packet
, Head
, Option
, OptLen
);
412 Status
= Ip4SendFrame (IpIf
, IpInstance
, Packet
, GateWay
, Callback
, Context
);
414 if (EFI_ERROR (Status
)) {
421 Ip4CancelPacket (IpIf
, Packet
, Status
);
427 The filter function to find a packet and all its fragments.
428 The packet's fragments have their Context set to the packet.
430 @param[in] Frame The frames hold by the low level interface
431 @param[in] Context Context to the function, which is the packet.
433 @retval TRUE This is the packet to cancel or its fragments.
434 @retval FALSE This is unrelated packet.
438 Ip4CancelPacketFragments (
439 IN IP4_LINK_TX_TOKEN
*Frame
,
443 if ((Frame
->Packet
== (NET_BUF
*) Context
) || (Frame
->Context
== Context
)) {
452 Cancel the Packet and all its fragments.
454 @param IpIf The interface from which the Packet is sent
455 @param Packet The Packet to cancel
456 @param IoStatus The status returns to the sender.
461 IN IP4_INTERFACE
*IpIf
,
463 IN EFI_STATUS IoStatus
466 Ip4CancelFrames (IpIf
, IoStatus
, Ip4CancelPacketFragments
, Packet
);