1 /** @file
2 Routines to process Rrq (download).
3
4 (C) Copyright 2014 Hewlett-Packard Development Company, L.P.<BR>
5 Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
6 This program and the accompanying materials
7 are licensed and made available under the terms and conditions of the BSD License
8 which accompanies this distribution. The full text of the license may be found at
9 http://opensource.org/licenses/bsd-license.php<BR>
10
11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
13
14 **/
15
16
17 #include "Mtftp4Impl.h"
18
19
20 /**
21 The packet process callback for MTFTP download.
22
23 @param UdpPacket The packet received
24 @param EndPoint The local/remote access point of the packet
25 @param IoStatus The status of the receiving
26 @param Context Opaque parameter, which is the MTFTP session
27
28 **/
29 VOID
30 EFIAPI
31 Mtftp4RrqInput (
32 IN NET_BUF *UdpPacket,
33 IN UDP_END_POINT *EndPoint,
34 IN EFI_STATUS IoStatus,
35 IN VOID *Context
36 );
37
38
39 /**
40 Start the MTFTP session to download.
41
42 It will first initialize some of the internal states then build and send a RRQ
43 reqeuest packet, at last, it will start receive for the downloading.
44
45 @param Instance The Mtftp session
46 @param Operation The MTFTP opcode, it may be a EFI_MTFTP4_OPCODE_RRQ
47 or EFI_MTFTP4_OPCODE_DIR.
48
49 @retval EFI_SUCCESS The mtftp download session is started.
50 @retval Others Failed to start downloading.
51
52 **/
53 EFI_STATUS
Mtftp4RrqStart(IN MTFTP4_PROTOCOL * Instance,IN UINT16 Operation)54 Mtftp4RrqStart (
55 IN MTFTP4_PROTOCOL *Instance,
56 IN UINT16 Operation
57 )
58 {
59 EFI_STATUS Status;
60
61 //
62 // The valid block number range are [1, 0xffff]. For example:
63 // the client sends an RRQ request to the server, the server
64 // transfers the DATA1 block. If option negoitation is ongoing,
65 // the server will send back an OACK, then client will send ACK0.
66 //
67 Status = Mtftp4InitBlockRange (&Instance->Blocks, 1, 0xffff);
68
69 if (EFI_ERROR (Status)) {
70 return Status;
71 }
72
73 Status = Mtftp4SendRequest (Instance);
74
75 if (EFI_ERROR (Status)) {
76 return Status;
77 }
78
79 return UdpIoRecvDatagram (Instance->UnicastPort, Mtftp4RrqInput, Instance, 0);
80 }
81
82
83 /**
84 Build and send a ACK packet for the download session.
85
86 @param Instance The Mtftp session
87 @param BlkNo The BlkNo to ack.
88
89 @retval EFI_OUT_OF_RESOURCES Failed to allocate memory for the packet
90 @retval EFI_SUCCESS The ACK has been sent
91 @retval Others Failed to send the ACK.
92
93 **/
94 EFI_STATUS
Mtftp4RrqSendAck(IN MTFTP4_PROTOCOL * Instance,IN UINT16 BlkNo)95 Mtftp4RrqSendAck (
96 IN MTFTP4_PROTOCOL *Instance,
97 IN UINT16 BlkNo
98 )
99 {
100 EFI_MTFTP4_PACKET *Ack;
101 NET_BUF *Packet;
102
103 Packet = NetbufAlloc (sizeof (EFI_MTFTP4_ACK_HEADER));
104 if (Packet == NULL) {
105 return EFI_OUT_OF_RESOURCES;
106 }
107
108 Ack = (EFI_MTFTP4_PACKET *) NetbufAllocSpace (
109 Packet,
110 sizeof (EFI_MTFTP4_ACK_HEADER),
111 FALSE
112 );
113 ASSERT (Ack != NULL);
114
115 Ack->Ack.OpCode = HTONS (EFI_MTFTP4_OPCODE_ACK);
116 Ack->Ack.Block[0] = HTONS (BlkNo);
117
118 return Mtftp4SendPacket (Instance, Packet);
119 }
120
121
122 /**
123 Deliver the received data block to the user, which can be saved
124 in the user provide buffer or through the CheckPacket callback.
125
126 @param Instance The Mtftp session
127 @param Packet The received data packet
128 @param Len The packet length
129
130 @retval EFI_SUCCESS The data is saved successfully
131 @retval EFI_ABORTED The user tells to abort by return an error through
132 CheckPacket
133 @retval EFI_BUFFER_TOO_SMALL The user's buffer is too small and buffer length is
134 updated to the actual buffer size needed.
135
136 **/
137 EFI_STATUS
Mtftp4RrqSaveBlock(IN OUT MTFTP4_PROTOCOL * Instance,IN EFI_MTFTP4_PACKET * Packet,IN UINT32 Len)138 Mtftp4RrqSaveBlock (
139 IN OUT MTFTP4_PROTOCOL *Instance,
140 IN EFI_MTFTP4_PACKET *Packet,
141 IN UINT32 Len
142 )
143 {
144 EFI_MTFTP4_TOKEN *Token;
145 EFI_STATUS Status;
146 UINT16 Block;
147 UINT64 Start;
148 UINT32 DataLen;
149 UINT64 TotalBlock;
150 BOOLEAN Completed;
151
152 Completed = FALSE;
153 Token = Instance->Token;
154 Block = NTOHS (Packet->Data.Block);
155 DataLen = Len - MTFTP4_DATA_HEAD_LEN;
156
157 //
158 // This is the last block, save the block no
159 //
160 if (DataLen < Instance->BlkSize) {
161 Completed = TRUE;
162 Instance->LastBlock = Block;
163 Mtftp4SetLastBlockNum (&Instance->Blocks, Block);
164 }
165
166 //
167 // Remove this block number from the file hole. If Mtftp4RemoveBlockNum
168 // returns EFI_NOT_FOUND, the block has been saved, don't save it again.
169 // Note that : For bigger files, allowing the block counter to roll over
170 // to accept transfers of unlimited size. So TotalBlock is memorised as
171 // continuous block counter.
172 //
173 Status = Mtftp4RemoveBlockNum (&Instance->Blocks, Block, Completed, &TotalBlock);
174
175 if (Status == EFI_NOT_FOUND) {
176 return EFI_SUCCESS;
177 } else if (EFI_ERROR (Status)) {
178 return Status;
179 }
180
181 if (Token->CheckPacket != NULL) {
182 Status = Token->CheckPacket (&Instance->Mtftp4, Token, (UINT16) Len, Packet);
183
184 if (EFI_ERROR (Status)) {
185 Mtftp4SendError (
186 Instance,
187 EFI_MTFTP4_ERRORCODE_ILLEGAL_OPERATION,
188 (UINT8 *) "User aborted download"
189 );
190
191 return EFI_ABORTED;
192 }
193 }
194
195 if (Token->Buffer != NULL) {
196 Start = MultU64x32 (TotalBlock - 1, Instance->BlkSize);
197
198 if (Start + DataLen <= Token->BufferSize) {
199 CopyMem ((UINT8 *) Token->Buffer + Start, Packet->Data.Data, DataLen);
200
201 //
202 // Update the file size when received the last block
203 //
204 if ((Instance->LastBlock == Block) && Completed) {
205 Token->BufferSize = Start + DataLen;
206 }
207
208 } else if (Instance->LastBlock != 0) {
209 //
210 // Don't save the data if the buffer is too small, return
211 // EFI_BUFFER_TOO_SMALL if received the last packet. This
212 // will give a accurate file length.
213 //
214 Token->BufferSize = Start + DataLen;
215
216 Mtftp4SendError (
217 Instance,
218 EFI_MTFTP4_ERRORCODE_DISK_FULL,
219 (UINT8 *) "User provided memory block is too small"
220 );
221
222 return EFI_BUFFER_TOO_SMALL;
223 }
224 }
225
226 return EFI_SUCCESS;
227 }
228
229
230 /**
231 Function to process the received data packets.
232
233 It will save the block then send back an ACK if it is active.
234
235 @param Instance The downloading MTFTP session
236 @param Packet The packet received
237 @param Len The length of the packet
238 @param Multicast Whether this packet is multicast or unicast
239 @param Completed Return whether the download has completed
240
241 @retval EFI_SUCCESS The data packet is successfully processed
242 @retval EFI_ABORTED The download is aborted by the user
243 @retval EFI_BUFFER_TOO_SMALL The user provided buffer is too small
244
245 **/
246 EFI_STATUS
Mtftp4RrqHandleData(IN MTFTP4_PROTOCOL * Instance,IN EFI_MTFTP4_PACKET * Packet,IN UINT32 Len,IN BOOLEAN Multicast,OUT BOOLEAN * Completed)247 Mtftp4RrqHandleData (
248 IN MTFTP4_PROTOCOL *Instance,
249 IN EFI_MTFTP4_PACKET *Packet,
250 IN UINT32 Len,
251 IN BOOLEAN Multicast,
252 OUT BOOLEAN *Completed
253 )
254 {
255 EFI_STATUS Status;
256 UINT16 BlockNum;
257 INTN Expected;
258
259 *Completed = FALSE;
260 BlockNum = NTOHS (Packet->Data.Block);
261 Expected = Mtftp4GetNextBlockNum (&Instance->Blocks);
262
263 ASSERT (Expected >= 0);
264
265 //
266 // If we are active and received an unexpected packet, retransmit
267 // the last ACK then restart receiving. If we are passive, save
268 // the block.
269 //
270 if (Instance->Master && (Expected != BlockNum)) {
271 Mtftp4Retransmit (Instance);
272 return EFI_SUCCESS;
273 }
274
275 Status = Mtftp4RrqSaveBlock (Instance, Packet, Len);
276
277 if (EFI_ERROR (Status)) {
278 return Status;
279 }
280
281 //
282 // Reset the passive client's timer whenever it received a
283 // valid data packet.
284 //
285 if (!Instance->Master) {
286 Mtftp4SetTimeout (Instance);
287 }
288
289 //
290 // Check whether we have received all the blocks. Send the ACK if we
291 // are active (unicast client or master client for multicast download).
292 // If we have received all the blocks, send an ACK even if we are passive
293 // to tell the server that we are done.
294 //
295 Expected = Mtftp4GetNextBlockNum (&Instance->Blocks);
296
297 if (Instance->Master || (Expected < 0)) {
298 if (Expected < 0) {
299 //
300 // If we are passive client, then the just received Block maybe
301 // isn't the last block. We need to send an ACK to the last block
302 // to inform the server that we are done. If we are active client,
303 // the Block == Instance->LastBlock.
304 //
305 BlockNum = Instance->LastBlock;
306 *Completed = TRUE;
307
308 } else {
309 BlockNum = (UINT16) (Expected - 1);
310 }
311
312 Mtftp4RrqSendAck (Instance, BlockNum);
313 }
314
315 return EFI_SUCCESS;
316 }
317
318
319 /**
320 Validate whether the options received in the server's OACK packet is valid.
321
322 The options are valid only if:
323 1. The server doesn't include options not requested by us
324 2. The server can only use smaller blksize than that is requested
325 3. The server can only use the same timeout as requested
326 4. The server doesn't change its multicast channel.
327
328 @param This The downloading Mtftp session
329 @param Reply The options in the OACK packet
330 @param Request The requested options
331
332 @retval TRUE The options in the OACK is OK.
333 @retval FALSE The options in the OACK is invalid.
334
335 **/
336 BOOLEAN
Mtftp4RrqOackValid(IN MTFTP4_PROTOCOL * This,IN MTFTP4_OPTION * Reply,IN MTFTP4_OPTION * Request)337 Mtftp4RrqOackValid (
338 IN MTFTP4_PROTOCOL *This,
339 IN MTFTP4_OPTION *Reply,
340 IN MTFTP4_OPTION *Request
341 )
342 {
343
344 //
345 // It is invalid for server to return options we don't request
346 //
347 if ((Reply->Exist &~Request->Exist) != 0) {
348 return FALSE;
349 }
350
351 //
352 // Server can only specify a smaller block size to be used and
353 // return the timeout matches that requested.
354 //
355 if ((((Reply->Exist & MTFTP4_BLKSIZE_EXIST) != 0)&& (Reply->BlkSize > Request->BlkSize)) ||
356 (((Reply->Exist & MTFTP4_TIMEOUT_EXIST) != 0) && (Reply->Timeout != Request->Timeout))) {
357 return FALSE;
358 }
359
360 //
361 // The server can send ",,master" to client to change its master
362 // setting. But if it use the specific multicast channel, it can't
363 // change the setting.
364 //
365 if (((Reply->Exist & MTFTP4_MCAST_EXIST) != 0) && (This->McastIp != 0)) {
366 if ((Reply->McastIp != 0) && (Reply->McastIp != This->McastIp)) {
367 return FALSE;
368 }
369
370 if ((Reply->McastPort != 0) && (Reply->McastPort != This->McastPort)) {
371 return FALSE;
372 }
373 }
374
375 return TRUE;
376 }
377
378
379 /**
380 Configure a UDP IO port to receive the multicast.
381
382 @param McastIo The UDP IO to configure
383 @param Context The opaque parameter to the function which is the
384 MTFTP session.
385
386 @retval EFI_SUCCESS The UDP child is successfully configured.
387 @retval Others Failed to configure the UDP child.
388
389 **/
390 EFI_STATUS
391 EFIAPI
Mtftp4RrqConfigMcastPort(IN UDP_IO * McastIo,IN VOID * Context)392 Mtftp4RrqConfigMcastPort (
393 IN UDP_IO *McastIo,
394 IN VOID *Context
395 )
396 {
397 MTFTP4_PROTOCOL *Instance;
398 EFI_MTFTP4_CONFIG_DATA *Config;
399 EFI_UDP4_CONFIG_DATA UdpConfig;
400 EFI_IPv4_ADDRESS Group;
401 EFI_STATUS Status;
402 IP4_ADDR Ip;
403
404 Instance = (MTFTP4_PROTOCOL *) Context;
405 Config = &Instance->Config;
406
407 UdpConfig.AcceptBroadcast = FALSE;
408 UdpConfig.AcceptPromiscuous = FALSE;
409 UdpConfig.AcceptAnyPort = FALSE;
410 UdpConfig.AllowDuplicatePort = FALSE;
411 UdpConfig.TypeOfService = 0;
412 UdpConfig.TimeToLive = 64;
413 UdpConfig.DoNotFragment = FALSE;
414 UdpConfig.ReceiveTimeout = 0;
415 UdpConfig.TransmitTimeout = 0;
416 UdpConfig.UseDefaultAddress = Config->UseDefaultSetting;
417 IP4_COPY_ADDRESS (&UdpConfig.StationAddress, &Config->StationIp);
418 IP4_COPY_ADDRESS (&UdpConfig.SubnetMask, &Config->SubnetMask);
419 UdpConfig.StationPort = Instance->McastPort;
420 UdpConfig.RemotePort = 0;
421
422 Ip = HTONL (Instance->ServerIp);
423 IP4_COPY_ADDRESS (&UdpConfig.RemoteAddress, &Ip);
424
425 Status = McastIo->Protocol.Udp4->Configure (McastIo->Protocol.Udp4, &UdpConfig);
426
427 if (EFI_ERROR (Status)) {
428 return Status;
429 }
430
431 if (!Config->UseDefaultSetting &&
432 !EFI_IP4_EQUAL (&mZeroIp4Addr, &Config->GatewayIp)) {
433 //
434 // The station IP address is manually configured and the Gateway IP is not 0.
435 // Add the default route for this UDP instance.
436 //
437 Status = McastIo->Protocol.Udp4->Routes (
438 McastIo->Protocol.Udp4,
439 FALSE,
440 &mZeroIp4Addr,
441 &mZeroIp4Addr,
442 &Config->GatewayIp
443 );
444
445 if (EFI_ERROR (Status)) {
446 McastIo->Protocol.Udp4->Configure (McastIo->Protocol.Udp4, NULL);
447 return Status;
448 }
449 }
450
451 //
452 // join the multicast group
453 //
454 Ip = HTONL (Instance->McastIp);
455 IP4_COPY_ADDRESS (&Group, &Ip);
456
457 return McastIo->Protocol.Udp4->Groups (McastIo->Protocol.Udp4, TRUE, &Group);
458 }
459
460
461 /**
462 Function to process the OACK.
463
464 It will first validate the OACK packet, then update the various negotiated parameters.
465
466 @param Instance The download MTFTP session
467 @param Packet The packet received
468 @param Len The packet length
469 @param Multicast Whether this packet is received as a multicast
470 @param Completed Returns whether the download has completed. NOT
471 used by this function.
472
473 @retval EFI_DEVICE_ERROR Failed to create/start a multicast UDP child
474 @retval EFI_TFTP_ERROR Some error happened during the process
475 @retval EFI_SUCCESS The OACK is successfully processed.
476
477 **/
478 EFI_STATUS
Mtftp4RrqHandleOack(IN OUT MTFTP4_PROTOCOL * Instance,IN EFI_MTFTP4_PACKET * Packet,IN UINT32 Len,IN BOOLEAN Multicast,OUT BOOLEAN * Completed)479 Mtftp4RrqHandleOack (
480 IN OUT MTFTP4_PROTOCOL *Instance,
481 IN EFI_MTFTP4_PACKET *Packet,
482 IN UINT32 Len,
483 IN BOOLEAN Multicast,
484 OUT BOOLEAN *Completed
485 )
486 {
487 MTFTP4_OPTION Reply;
488 EFI_STATUS Status;
489 INTN Expected;
490 EFI_UDP4_PROTOCOL *Udp4;
491
492 *Completed = FALSE;
493
494 //
495 // If already started the master download, don't change the
496 // setting. Master download always succeeds.
497 //
498 Expected = Mtftp4GetNextBlockNum (&Instance->Blocks);
499 ASSERT (Expected != -1);
500
501 if (Instance->Master && (Expected != 1)) {
502 return EFI_SUCCESS;
503 }
504
505 //
506 // Parse and validate the options from server
507 //
508 ZeroMem (&Reply, sizeof (MTFTP4_OPTION));
509
510 Status = Mtftp4ParseOptionOack (Packet, Len, &Reply);
511
512 if (EFI_ERROR (Status) ||
513 !Mtftp4RrqOackValid (Instance, &Reply, &Instance->RequestOption)) {
514 //
515 // Don't send an ERROR packet if the error is EFI_OUT_OF_RESOURCES.
516 //
517 if (Status != EFI_OUT_OF_RESOURCES) {
518 Mtftp4SendError (
519 Instance,
520 EFI_MTFTP4_ERRORCODE_ILLEGAL_OPERATION,
521 (UINT8 *) "Mal-formated OACK packet"
522 );
523 }
524
525 return EFI_TFTP_ERROR;
526 }
527
528 if ((Reply.Exist & MTFTP4_MCAST_EXIST) != 0) {
529
530 //
531 // Save the multicast info. Always update the Master, only update the
532 // multicast IP address, block size, timeoute at the first time. If IP
533 // address is updated, create a UDP child to receive the multicast.
534 //
535 Instance->Master = Reply.Master;
536
537 if (Instance->McastIp == 0) {
538 if ((Reply.McastIp == 0) || (Reply.McastPort == 0)) {
539 Mtftp4SendError (
540 Instance,
541 EFI_MTFTP4_ERRORCODE_ILLEGAL_OPERATION,
542 (UINT8 *) "Illegal multicast setting"
543 );
544
545 return EFI_TFTP_ERROR;
546 }
547
548 //
549 // Create a UDP child then start receive the multicast from it.
550 //
551 Instance->McastIp = Reply.McastIp;
552 Instance->McastPort = Reply.McastPort;
553 if (Instance->McastUdpPort == NULL) {
554 Instance->McastUdpPort = UdpIoCreateIo (
555 Instance->Service->Controller,
556 Instance->Service->Image,
557 Mtftp4RrqConfigMcastPort,
558 UDP_IO_UDP4_VERSION,
559 Instance
560 );
561 if (Instance->McastUdpPort != NULL) {
562 Status = gBS->OpenProtocol (
563 Instance->McastUdpPort->UdpHandle,
564 &gEfiUdp4ProtocolGuid,
565 (VOID **) &Udp4,
566 Instance->Service->Image,
567 Instance->Handle,
568 EFI_OPEN_PROTOCOL_BY_CHILD_CONTROLLER
569 );
570 if (EFI_ERROR (Status)) {
571 UdpIoFreeIo (Instance->McastUdpPort);
572 Instance->McastUdpPort = NULL;
573 return EFI_DEVICE_ERROR;
574 }
575 }
576 }
577
578
579 if (Instance->McastUdpPort == NULL) {
580 return EFI_DEVICE_ERROR;
581 }
582
583 Status = UdpIoRecvDatagram (Instance->McastUdpPort, Mtftp4RrqInput, Instance, 0);
584
585 if (EFI_ERROR (Status)) {
586 Mtftp4SendError (
587 Instance,
588 EFI_MTFTP4_ERRORCODE_ACCESS_VIOLATION,
589 (UINT8 *) "Failed to create socket to receive multicast packet"
590 );
591
592 return Status;
593 }
594
595 //
596 // Update the parameters used.
597 //
598 if (Reply.BlkSize != 0) {
599 Instance->BlkSize = Reply.BlkSize;
600 }
601
602 if (Reply.Timeout != 0) {
603 Instance->Timeout = Reply.Timeout;
604 }
605 }
606
607 } else {
608 Instance->Master = TRUE;
609
610 if (Reply.BlkSize != 0) {
611 Instance->BlkSize = Reply.BlkSize;
612 }
613
614 if (Reply.Timeout != 0) {
615 Instance->Timeout = Reply.Timeout;
616 }
617 }
618
619 //
620 // Send an ACK to (Expected - 1) which is 0 for unicast download,
621 // or tell the server we want to receive the Expected block.
622 //
623 return Mtftp4RrqSendAck (Instance, (UINT16) (Expected - 1));
624 }
625
626
627 /**
628 The packet process callback for MTFTP download.
629
630 @param UdpPacket The packet received
631 @param EndPoint The local/remote access point of the packet
632 @param IoStatus The status of the receiving
633 @param Context Opaque parameter, which is the MTFTP session
634
635 **/
636 VOID
637 EFIAPI
Mtftp4RrqInput(IN NET_BUF * UdpPacket,IN UDP_END_POINT * EndPoint,IN EFI_STATUS IoStatus,IN VOID * Context)638 Mtftp4RrqInput (
639 IN NET_BUF *UdpPacket,
640 IN UDP_END_POINT *EndPoint,
641 IN EFI_STATUS IoStatus,
642 IN VOID *Context
643 )
644 {
645 MTFTP4_PROTOCOL *Instance;
646 EFI_MTFTP4_PACKET *Packet;
647 BOOLEAN Completed;
648 BOOLEAN Multicast;
649 EFI_STATUS Status;
650 UINT16 Opcode;
651 UINT32 Len;
652
653 Instance = (MTFTP4_PROTOCOL *) Context;
654 NET_CHECK_SIGNATURE (Instance, MTFTP4_PROTOCOL_SIGNATURE);
655
656 Status = EFI_SUCCESS;
657 Packet = NULL;
658 Completed = FALSE;
659 Multicast = FALSE;
660
661 if (EFI_ERROR (IoStatus)) {
662 Status = IoStatus;
663 goto ON_EXIT;
664 }
665
666 ASSERT (UdpPacket != NULL);
667
668 //
669 // Find the port this packet is from to restart receive correctly.
670 //
671 Multicast = (BOOLEAN) (EndPoint->LocalAddr.Addr[0] == Instance->McastIp);
672
673 if (UdpPacket->TotalSize < MTFTP4_OPCODE_LEN) {
674 goto ON_EXIT;
675 }
676
677 //
678 // Client send initial request to server's listening port. Server
679 // will select a UDP port to communicate with the client. The server
680 // is required to use the same port as RemotePort to multicast the
681 // data.
682 //
683 if (EndPoint->RemotePort != Instance->ConnectedPort) {
684 if (Instance->ConnectedPort != 0) {
685 goto ON_EXIT;
686 } else {
687 Instance->ConnectedPort = EndPoint->RemotePort;
688 }
689 }
690
691 //
692 // Copy the MTFTP packet to a continuous buffer if it isn't already so.
693 //
694 Len = UdpPacket->TotalSize;
695
696 if (UdpPacket->BlockOpNum > 1) {
697 Packet = AllocatePool (Len);
698
699 if (Packet == NULL) {
700 Status = EFI_OUT_OF_RESOURCES;
701 goto ON_EXIT;
702 }
703
704 NetbufCopy (UdpPacket, 0, Len, (UINT8 *) Packet);
705
706 } else {
707 Packet = (EFI_MTFTP4_PACKET *) NetbufGetByte (UdpPacket, 0, NULL);
708 ASSERT (Packet != NULL);
709 }
710
711 Opcode = NTOHS (Packet->OpCode);
712
713 //
714 // Call the user's CheckPacket if provided. Abort the transmission
715 // if CheckPacket returns an EFI_ERROR code.
716 //
717 if ((Instance->Token->CheckPacket != NULL) &&
718 ((Opcode == EFI_MTFTP4_OPCODE_OACK) || (Opcode == EFI_MTFTP4_OPCODE_ERROR))) {
719
720 Status = Instance->Token->CheckPacket (
721 &Instance->Mtftp4,
722 Instance->Token,
723 (UINT16) Len,
724 Packet
725 );
726
727 if (EFI_ERROR (Status)) {
728 //
729 // Send an error message to the server to inform it
730 //
731 if (Opcode != EFI_MTFTP4_OPCODE_ERROR) {
732 Mtftp4SendError (
733 Instance,
734 EFI_MTFTP4_ERRORCODE_REQUEST_DENIED,
735 (UINT8 *) "User aborted the transfer"
736 );
737 }
738
739 Status = EFI_ABORTED;
740 goto ON_EXIT;
741 }
742 }
743
744 switch (Opcode) {
745 case EFI_MTFTP4_OPCODE_DATA:
746 if ((Len > (UINT32) (MTFTP4_DATA_HEAD_LEN + Instance->BlkSize)) ||
747 (Len < (UINT32) MTFTP4_DATA_HEAD_LEN)) {
748 goto ON_EXIT;
749 }
750
751 Status = Mtftp4RrqHandleData (Instance, Packet, Len, Multicast, &Completed);
752 break;
753
754 case EFI_MTFTP4_OPCODE_OACK:
755 if (Multicast || (Len <= MTFTP4_OPCODE_LEN)) {
756 goto ON_EXIT;
757 }
758
759 Status = Mtftp4RrqHandleOack (Instance, Packet, Len, Multicast, &Completed);
760 break;
761
762 case EFI_MTFTP4_OPCODE_ERROR:
763 Status = EFI_TFTP_ERROR;
764 break;
765
766 default:
767 break;
768 }
769
770 ON_EXIT:
771
772 //
773 // Free the resources, then if !EFI_ERROR (Status), restart the
774 // receive, otherwise end the session.
775 //
776 if ((Packet != NULL) && (UdpPacket->BlockOpNum > 1)) {
777 FreePool (Packet);
778 }
779
780 if (UdpPacket != NULL) {
781 NetbufFree (UdpPacket);
782 }
783
784 if (!EFI_ERROR (Status) && !Completed) {
785 if (Multicast) {
786 Status = UdpIoRecvDatagram (Instance->McastUdpPort, Mtftp4RrqInput, Instance, 0);
787 } else {
788 Status = UdpIoRecvDatagram (Instance->UnicastPort, Mtftp4RrqInput, Instance, 0);
789 }
790 }
791
792 if (EFI_ERROR (Status) || Completed) {
793 Mtftp4CleanOperation (Instance, Status);
794 }
795 }
796