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Add memtest support.
[syslinux-debian/hramrach.git] / gpxe / src / net / tcp / iscsi.c
blob771384b948b419639b345dc304bf9644946a34bb
1 /*
2 * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17 */
18
19 FILE_LICENCE ( GPL2_OR_LATER );
20
21 #include <stddef.h>
22 #include <string.h>
23 #include <stdlib.h>
24 #include <stdio.h>
25 #include <errno.h>
26 #include <assert.h>
27 #include <byteswap.h>
28 #include <gpxe/vsprintf.h>
29 #include <gpxe/socket.h>
30 #include <gpxe/xfer.h>
31 #include <gpxe/open.h>
32 #include <gpxe/scsi.h>
33 #include <gpxe/process.h>
34 #include <gpxe/uaccess.h>
35 #include <gpxe/tcpip.h>
36 #include <gpxe/settings.h>
37 #include <gpxe/features.h>
38 #include <gpxe/iscsi.h>
39
40 /** @file
41 *
42 * iSCSI protocol
43 *
44 */
45
46 FEATURE ( FEATURE_PROTOCOL, "iSCSI", DHCP_EB_FEATURE_ISCSI, 1 );
47
48 /** iSCSI initiator name (explicitly specified) */
49 static char *iscsi_explicit_initiator_iqn;
50
51 /** Default iSCSI initiator name (constructed from hostname) */
52 static char *iscsi_default_initiator_iqn;
53
54 /** iSCSI initiator username */
55 static char *iscsi_initiator_username;
56
57 /** iSCSI initiator password */
58 static char *iscsi_initiator_password;
59
60 /** iSCSI target username */
61 static char *iscsi_target_username;
62
63 /** iSCSI target password */
64 static char *iscsi_target_password;
65
66 static void iscsi_start_tx ( struct iscsi_session *iscsi );
67 static void iscsi_start_login ( struct iscsi_session *iscsi );
68 static void iscsi_start_data_out ( struct iscsi_session *iscsi,
69 unsigned int datasn );
70
71 /**
72 * Finish receiving PDU data into buffer
73 *
74 * @v iscsi iSCSI session
75 */
76 static void iscsi_rx_buffered_data_done ( struct iscsi_session *iscsi ) {
77 free ( iscsi->rx_buffer );
78 iscsi->rx_buffer = NULL;
79 }
80
81 /**
82 * Free iSCSI session
83 *
84 * @v refcnt Reference counter
85 */
86 static void iscsi_free ( struct refcnt *refcnt ) {
87 struct iscsi_session *iscsi =
88 container_of ( refcnt, struct iscsi_session, refcnt );
89
90 free ( iscsi->target_address );
91 free ( iscsi->target_iqn );
92 free ( iscsi->initiator_username );
93 free ( iscsi->initiator_password );
94 free ( iscsi->target_username );
95 free ( iscsi->target_password );
96 chap_finish ( &iscsi->chap );
97 iscsi_rx_buffered_data_done ( iscsi );
98 free ( iscsi );
99 }
100
101 /**
102 * Open iSCSI transport-layer connection
103 *
104 * @v iscsi iSCSI session
105 * @ret rc Return status code
106 */
107 static int iscsi_open_connection ( struct iscsi_session *iscsi ) {
108 struct sockaddr_tcpip target;
109 int rc;
110
111 assert ( iscsi->tx_state == ISCSI_TX_IDLE );
112 assert ( iscsi->rx_state == ISCSI_RX_BHS );
113 assert ( iscsi->rx_offset == 0 );
114
115 /* Open socket */
116 memset ( &target, 0, sizeof ( target ) );
117 target.st_port = htons ( iscsi->target_port );
118 if ( ( rc = xfer_open_named_socket ( &iscsi->socket, SOCK_STREAM,
119 ( struct sockaddr * ) &target,
120 iscsi->target_address,
121 NULL ) ) != 0 ) {
122 DBGC ( iscsi, "iSCSI %p could not open socket: %s\n",
123 iscsi, strerror ( rc ) );
124 return rc;
125 }
126
127 /* Enter security negotiation phase */
128 iscsi->status = ( ISCSI_STATUS_SECURITY_NEGOTIATION_PHASE |
129 ISCSI_STATUS_STRINGS_SECURITY );
130 if ( iscsi->target_username )
131 iscsi->status |= ISCSI_STATUS_AUTH_REVERSE_REQUIRED;
132
133 /* Assign fresh initiator task tag */
134 iscsi->itt++;
135
136 /* Initiate login */
137 iscsi_start_login ( iscsi );
138
139 return 0;
140 }
141
142 /**
143 * Close iSCSI transport-layer connection
144 *
145 * @v iscsi iSCSI session
146 * @v rc Reason for close
147 *
148 * Closes the transport-layer connection and resets the session state
149 * ready to attempt a fresh login.
150 */
151 static void iscsi_close_connection ( struct iscsi_session *iscsi, int rc ) {
152
153 /* Close all data transfer interfaces */
154 xfer_close ( &iscsi->socket, rc );
155
156 /* Clear connection status */
157 iscsi->status = 0;
158
159 /* Reset TX and RX state machines */
160 iscsi->tx_state = ISCSI_TX_IDLE;
161 iscsi->rx_state = ISCSI_RX_BHS;
162 iscsi->rx_offset = 0;
163
164 /* Free any temporary dynamically allocated memory */
165 chap_finish ( &iscsi->chap );
166 iscsi_rx_buffered_data_done ( iscsi );
167 }
168
169 /**
170 * Mark iSCSI SCSI operation as complete
171 *
172 * @v iscsi iSCSI session
173 * @v rc Return status code
174 *
175 * Note that iscsi_scsi_done() will not close the connection, and must
176 * therefore be called only when the internal state machines are in an
177 * appropriate state, otherwise bad things may happen on the next call
178 * to iscsi_issue(). The general rule is to call iscsi_scsi_done()
179 * only at the end of receiving a PDU; at this point the TX and RX
180 * engines should both be idle.
181 */
182 static void iscsi_scsi_done ( struct iscsi_session *iscsi, int rc ) {
183
184 assert ( iscsi->tx_state == ISCSI_TX_IDLE );
185 assert ( iscsi->command != NULL );
186
187 iscsi->command->rc = rc;
188 iscsi->command = NULL;
189 }
190
191 /****************************************************************************
192 *
193 * iSCSI SCSI command issuing
194 *
195 */
196
197 /**
198 * Build iSCSI SCSI command BHS
199 *
200 * @v iscsi iSCSI session
201 *
202 * We don't currently support bidirectional commands (i.e. with both
203 * Data-In and Data-Out segments); these would require providing code
204 * to generate an AHS, and there doesn't seem to be any need for it at
205 * the moment.
206 */
207 static void iscsi_start_command ( struct iscsi_session *iscsi ) {
208 struct iscsi_bhs_scsi_command *command = &iscsi->tx_bhs.scsi_command;
209
210 assert ( ! ( iscsi->command->data_in && iscsi->command->data_out ) );
211
212 /* Construct BHS and initiate transmission */
213 iscsi_start_tx ( iscsi );
214 command->opcode = ISCSI_OPCODE_SCSI_COMMAND;
215 command->flags = ( ISCSI_FLAG_FINAL |
216 ISCSI_COMMAND_ATTR_SIMPLE );
217 if ( iscsi->command->data_in )
218 command->flags |= ISCSI_COMMAND_FLAG_READ;
219 if ( iscsi->command->data_out )
220 command->flags |= ISCSI_COMMAND_FLAG_WRITE;
221 /* lengths left as zero */
222 command->lun = iscsi->lun;
223 command->itt = htonl ( ++iscsi->itt );
224 command->exp_len = htonl ( iscsi->command->data_in_len |
225 iscsi->command->data_out_len );
226 command->cmdsn = htonl ( iscsi->cmdsn );
227 command->expstatsn = htonl ( iscsi->statsn + 1 );
228 memcpy ( &command->cdb, &iscsi->command->cdb, sizeof ( command->cdb ));
229 DBGC2 ( iscsi, "iSCSI %p start " SCSI_CDB_FORMAT " %s %#zx\n",
230 iscsi, SCSI_CDB_DATA ( command->cdb ),
231 ( iscsi->command->data_in ? "in" : "out" ),
232 ( iscsi->command->data_in ?
233 iscsi->command->data_in_len :
234 iscsi->command->data_out_len ) );
235 }
236
237 /**
238 * Receive data segment of an iSCSI SCSI response PDU
239 *
240 * @v iscsi iSCSI session
241 * @v data Received data
242 * @v len Length of received data
243 * @v remaining Data remaining after this data
244 * @ret rc Return status code
245 */
246 static int iscsi_rx_scsi_response ( struct iscsi_session *iscsi,
247 const void *data, size_t len,
248 size_t remaining ) {
249 struct iscsi_bhs_scsi_response *response
250 = &iscsi->rx_bhs.scsi_response;
251 int sense_offset;
252
253 /* Capture the sense response code as it floats past, if present */
254 sense_offset = ISCSI_SENSE_RESPONSE_CODE_OFFSET - iscsi->rx_offset;
255 if ( ( sense_offset >= 0 ) && len ) {
256 iscsi->command->sense_response =
257 * ( ( char * ) data + sense_offset );
258 }
259
260 /* Wait for whole SCSI response to arrive */
261 if ( remaining )
262 return 0;
263
264 /* Record SCSI status code */
265 iscsi->command->status = response->status;
266
267 /* Check for errors */
268 if ( response->response != ISCSI_RESPONSE_COMMAND_COMPLETE )
269 return -EIO;
270
271 /* Mark as completed */
272 iscsi_scsi_done ( iscsi, 0 );
273 return 0;
274 }
275
276 /**
277 * Receive data segment of an iSCSI data-in PDU
278 *
279 * @v iscsi iSCSI session
280 * @v data Received data
281 * @v len Length of received data
282 * @v remaining Data remaining after this data
283 * @ret rc Return status code
284 */
285 static int iscsi_rx_data_in ( struct iscsi_session *iscsi,
286 const void *data, size_t len,
287 size_t remaining ) {
288 struct iscsi_bhs_data_in *data_in = &iscsi->rx_bhs.data_in;
289 unsigned long offset;
290
291 /* Copy data to data-in buffer */
292 offset = ntohl ( data_in->offset ) + iscsi->rx_offset;
293 assert ( iscsi->command != NULL );
294 assert ( iscsi->command->data_in );
295 assert ( ( offset + len ) <= iscsi->command->data_in_len );
296 copy_to_user ( iscsi->command->data_in, offset, data, len );
297
298 /* Wait for whole SCSI response to arrive */
299 if ( remaining )
300 return 0;
301
302 /* Mark as completed if status is present */
303 if ( data_in->flags & ISCSI_DATA_FLAG_STATUS ) {
304 assert ( ( offset + len ) == iscsi->command->data_in_len );
305 assert ( data_in->flags & ISCSI_FLAG_FINAL );
306 iscsi->command->status = data_in->status;
307 /* iSCSI cannot return an error status via a data-in */
308 iscsi_scsi_done ( iscsi, 0 );
309 }
310
311 return 0;
312 }
313
314 /**
315 * Receive data segment of an iSCSI R2T PDU
316 *
317 * @v iscsi iSCSI session
318 * @v data Received data
319 * @v len Length of received data
320 * @v remaining Data remaining after this data
321 * @ret rc Return status code
322 */
323 static int iscsi_rx_r2t ( struct iscsi_session *iscsi,
324 const void *data __unused, size_t len __unused,
325 size_t remaining __unused ) {
326 struct iscsi_bhs_r2t *r2t = &iscsi->rx_bhs.r2t;
327
328 /* Record transfer parameters and trigger first data-out */
329 iscsi->ttt = ntohl ( r2t->ttt );
330 iscsi->transfer_offset = ntohl ( r2t->offset );
331 iscsi->transfer_len = ntohl ( r2t->len );
332 iscsi_start_data_out ( iscsi, 0 );
333
334 return 0;
335 }
336
337 /**
338 * Build iSCSI data-out BHS
339 *
340 * @v iscsi iSCSI session
341 * @v datasn Data sequence number within the transfer
342 *
343 */
344 static void iscsi_start_data_out ( struct iscsi_session *iscsi,
345 unsigned int datasn ) {
346 struct iscsi_bhs_data_out *data_out = &iscsi->tx_bhs.data_out;
347 unsigned long offset;
348 unsigned long remaining;
349 unsigned long len;
350
351 /* We always send 512-byte Data-Out PDUs; this removes the
352 * need to worry about the target's MaxRecvDataSegmentLength.
353 */
354 offset = datasn * 512;
355 remaining = iscsi->transfer_len - offset;
356 len = remaining;
357 if ( len > 512 )
358 len = 512;
359
360 /* Construct BHS and initiate transmission */
361 iscsi_start_tx ( iscsi );
362 data_out->opcode = ISCSI_OPCODE_DATA_OUT;
363 if ( len == remaining )
364 data_out->flags = ( ISCSI_FLAG_FINAL );
365 ISCSI_SET_LENGTHS ( data_out->lengths, 0, len );
366 data_out->lun = iscsi->lun;
367 data_out->itt = htonl ( iscsi->itt );
368 data_out->ttt = htonl ( iscsi->ttt );
369 data_out->expstatsn = htonl ( iscsi->statsn + 1 );
370 data_out->datasn = htonl ( datasn );
371 data_out->offset = htonl ( iscsi->transfer_offset + offset );
372 DBGC ( iscsi, "iSCSI %p start data out DataSN %#x len %#lx\n",
373 iscsi, datasn, len );
374 }
375
376 /**
377 * Complete iSCSI data-out PDU transmission
378 *
379 * @v iscsi iSCSI session
380 *
381 */
382 static void iscsi_data_out_done ( struct iscsi_session *iscsi ) {
383 struct iscsi_bhs_data_out *data_out = &iscsi->tx_bhs.data_out;
384
385 /* If we haven't reached the end of the sequence, start
386 * sending the next data-out PDU.
387 */
388 if ( ! ( data_out->flags & ISCSI_FLAG_FINAL ) )
389 iscsi_start_data_out ( iscsi, ntohl ( data_out->datasn ) + 1 );
390 }
391
392 /**
393 * Send iSCSI data-out data segment
394 *
395 * @v iscsi iSCSI session
396 * @ret rc Return status code
397 */
398 static int iscsi_tx_data_out ( struct iscsi_session *iscsi ) {
399 struct iscsi_bhs_data_out *data_out = &iscsi->tx_bhs.data_out;
400 struct io_buffer *iobuf;
401 unsigned long offset;
402 size_t len;
403
404 offset = ntohl ( data_out->offset );
405 len = ISCSI_DATA_LEN ( data_out->lengths );
406
407 assert ( iscsi->command != NULL );
408 assert ( iscsi->command->data_out );
409 assert ( ( offset + len ) <= iscsi->command->data_out_len );
410
411 iobuf = xfer_alloc_iob ( &iscsi->socket, len );
412 if ( ! iobuf )
413 return -ENOMEM;
414
415 copy_from_user ( iob_put ( iobuf, len ),
416 iscsi->command->data_out, offset, len );
417
418 return xfer_deliver_iob ( &iscsi->socket, iobuf );
419 }
420
421 /****************************************************************************
422 *
423 * iSCSI login
424 *
425 */
426
427 /**
428 * Build iSCSI login request strings
429 *
430 * @v iscsi iSCSI session
431 *
432 * These are the initial set of strings sent in the first login
433 * request PDU. We want the following settings:
434 *
435 * HeaderDigest=None
436 * DataDigest=None
437 * MaxConnections is irrelevant; we make only one connection anyway
438 * InitialR2T=Yes [1]
439 * ImmediateData is irrelevant; we never send immediate data
440 * MaxRecvDataSegmentLength=8192 (default; we don't care) [3]
441 * MaxBurstLength=262144 (default; we don't care) [3]
442 * FirstBurstLength=262144 (default; we don't care)
443 * DefaultTime2Wait=0 [2]
444 * DefaultTime2Retain=0 [2]
445 * MaxOutstandingR2T=1
446 * DataPDUInOrder=Yes
447 * DataSequenceInOrder=Yes
448 * ErrorRecoveryLevel=0
449 *
450 * [1] InitialR2T has an OR resolution function, so the target may
451 * force us to use it. We therefore simplify our logic by always
452 * using it.
453 *
454 * [2] These ensure that we can safely start a new task once we have
455 * reconnected after a failure, without having to manually tidy up
456 * after the old one.
457 *
458 * [3] We are quite happy to use the RFC-defined default values for
459 * these parameters, but some targets (notably OpenSolaris)
460 * incorrectly assume a default value of zero, so we explicitly
461 * specify the default values.
462 */
463 static int iscsi_build_login_request_strings ( struct iscsi_session *iscsi,
464 void *data, size_t len ) {
465 unsigned int used = 0;
466 unsigned int i;
467 const char *auth_method;
468
469 if ( iscsi->status & ISCSI_STATUS_STRINGS_SECURITY ) {
470 /* Default to allowing no authentication */
471 auth_method = "None";
472 /* If we have a credential to supply, permit CHAP */
473 if ( iscsi->initiator_username )
474 auth_method = "CHAP,None";
475 /* If we have a credential to check, force CHAP */
476 if ( iscsi->target_username )
477 auth_method = "CHAP";
478 used += ssnprintf ( data + used, len - used,
479 "InitiatorName=%s%c"
480 "TargetName=%s%c"
481 "SessionType=Normal%c"
482 "AuthMethod=%s%c",
483 iscsi_initiator_iqn(), 0,
484 iscsi->target_iqn, 0, 0,
485 auth_method, 0 );
486 }
487
488 if ( iscsi->status & ISCSI_STATUS_STRINGS_CHAP_ALGORITHM ) {
489 used += ssnprintf ( data + used, len - used, "CHAP_A=5%c", 0 );
490 }
491
492 if ( ( iscsi->status & ISCSI_STATUS_STRINGS_CHAP_RESPONSE ) ) {
493 assert ( iscsi->initiator_username != NULL );
494 used += ssnprintf ( data + used, len - used,
495 "CHAP_N=%s%cCHAP_R=0x",
496 iscsi->initiator_username, 0 );
497 for ( i = 0 ; i < iscsi->chap.response_len ; i++ ) {
498 used += ssnprintf ( data + used, len - used, "%02x",
499 iscsi->chap.response[i] );
500 }
501 used += ssnprintf ( data + used, len - used, "%c", 0 );
502 }
503
504 if ( ( iscsi->status & ISCSI_STATUS_STRINGS_CHAP_CHALLENGE ) ) {
505 used += ssnprintf ( data + used, len - used,
506 "CHAP_I=%d%cCHAP_C=0x",
507 iscsi->chap_challenge[0], 0 );
508 for ( i = 1 ; i < sizeof ( iscsi->chap_challenge ) ; i++ ) {
509 used += ssnprintf ( data + used, len - used, "%02x",
510 iscsi->chap_challenge[i] );
511 }
512 used += ssnprintf ( data + used, len - used, "%c", 0 );
513 }
514
515 if ( iscsi->status & ISCSI_STATUS_STRINGS_OPERATIONAL ) {
516 used += ssnprintf ( data + used, len - used,
517 "HeaderDigest=None%c"
518 "DataDigest=None%c"
519 "InitialR2T=Yes%c"
520 "MaxRecvDataSegmentLength=8192%c"
521 "MaxBurstLength=262144%c"
522 "DefaultTime2Wait=0%c"
523 "DefaultTime2Retain=0%c"
524 "MaxOutstandingR2T=1%c"
525 "DataPDUInOrder=Yes%c"
526 "DataSequenceInOrder=Yes%c"
527 "ErrorRecoveryLevel=0%c",
528 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 );
529 }
530
531 return used;
532 }
533
534 /**
535 * Build iSCSI login request BHS
536 *
537 * @v iscsi iSCSI session
538 */
539 static void iscsi_start_login ( struct iscsi_session *iscsi ) {
540 struct iscsi_bhs_login_request *request = &iscsi->tx_bhs.login_request;
541 int len;
542
543 /* Construct BHS and initiate transmission */
544 iscsi_start_tx ( iscsi );
545 request->opcode = ( ISCSI_OPCODE_LOGIN_REQUEST |
546 ISCSI_FLAG_IMMEDIATE );
547 request->flags = ( ( iscsi->status & ISCSI_STATUS_PHASE_MASK ) |
548 ISCSI_LOGIN_FLAG_TRANSITION );
549 /* version_max and version_min left as zero */
550 len = iscsi_build_login_request_strings ( iscsi, NULL, 0 );
551 ISCSI_SET_LENGTHS ( request->lengths, 0, len );
552 request->isid_iana_en = htonl ( ISCSI_ISID_IANA |
553 IANA_EN_FEN_SYSTEMS );
554 /* isid_iana_qual left as zero */
555 request->tsih = htons ( iscsi->tsih );
556 request->itt = htonl ( iscsi->itt );
557 /* cid left as zero */
558 request->cmdsn = htonl ( iscsi->cmdsn );
559 request->expstatsn = htonl ( iscsi->statsn + 1 );
560 }
561
562 /**
563 * Complete iSCSI login request PDU transmission
564 *
565 * @v iscsi iSCSI session
566 *
567 */
568 static void iscsi_login_request_done ( struct iscsi_session *iscsi ) {
569
570 /* Clear any "strings to send" flags */
571 iscsi->status &= ~ISCSI_STATUS_STRINGS_MASK;
572
573 /* Free any dynamically allocated storage used for login */
574 chap_finish ( &iscsi->chap );
575 }
576
577 /**
578 * Transmit data segment of an iSCSI login request PDU
579 *
580 * @v iscsi iSCSI session
581 * @ret rc Return status code
582 *
583 * For login requests, the data segment consists of the login strings.
584 */
585 static int iscsi_tx_login_request ( struct iscsi_session *iscsi ) {
586 struct iscsi_bhs_login_request *request = &iscsi->tx_bhs.login_request;
587 struct io_buffer *iobuf;
588 size_t len;
589
590 len = ISCSI_DATA_LEN ( request->lengths );
591 iobuf = xfer_alloc_iob ( &iscsi->socket, len );
592 if ( ! iobuf )
593 return -ENOMEM;
594 iob_put ( iobuf, len );
595 iscsi_build_login_request_strings ( iscsi, iobuf->data, len );
596 return xfer_deliver_iob ( &iscsi->socket, iobuf );
597 }
598
599 /**
600 * Handle iSCSI TargetAddress text value
601 *
602 * @v iscsi iSCSI session
603 * @v value TargetAddress value
604 * @ret rc Return status code
605 */
606 static int iscsi_handle_targetaddress_value ( struct iscsi_session *iscsi,
607 const char *value ) {
608 char *separator;
609
610 DBGC ( iscsi, "iSCSI %p will redirect to %s\n", iscsi, value );
611
612 /* Replace target address */
613 free ( iscsi->target_address );
614 iscsi->target_address = strdup ( value );
615 if ( ! iscsi->target_address )
616 return -ENOMEM;
617
618 /* Replace target port */
619 iscsi->target_port = htons ( ISCSI_PORT );
620 separator = strchr ( iscsi->target_address, ':' );
621 if ( separator ) {
622 *separator = '\0';
623 iscsi->target_port = strtoul ( ( separator + 1 ), NULL, 0 );
624 }
625
626 return 0;
627 }
628
629 /**
630 * Handle iSCSI AuthMethod text value
631 *
632 * @v iscsi iSCSI session
633 * @v value AuthMethod value
634 * @ret rc Return status code
635 */
636 static int iscsi_handle_authmethod_value ( struct iscsi_session *iscsi,
637 const char *value ) {
638
639 /* If server requests CHAP, send the CHAP_A string */
640 if ( strcmp ( value, "CHAP" ) == 0 ) {
641 DBGC ( iscsi, "iSCSI %p initiating CHAP authentication\n",
642 iscsi );
643 iscsi->status |= ( ISCSI_STATUS_STRINGS_CHAP_ALGORITHM |
644 ISCSI_STATUS_AUTH_FORWARD_REQUIRED );
645 }
646
647 return 0;
648 }
649
650 /**
651 * Handle iSCSI CHAP_A text value
652 *
653 * @v iscsi iSCSI session
654 * @v value CHAP_A value
655 * @ret rc Return status code
656 */
657 static int iscsi_handle_chap_a_value ( struct iscsi_session *iscsi,
658 const char *value ) {
659
660 /* We only ever offer "5" (i.e. MD5) as an algorithm, so if
661 * the server responds with anything else it is a protocol
662 * violation.
663 */
664 if ( strcmp ( value, "5" ) != 0 ) {
665 DBGC ( iscsi, "iSCSI %p got invalid CHAP algorithm \"%s\"\n",
666 iscsi, value );
667 return -EPROTO;
668 }
669
670 return 0;
671 }
672
673 /**
674 * Handle iSCSI CHAP_I text value
675 *
676 * @v iscsi iSCSI session
677 * @v value CHAP_I value
678 * @ret rc Return status code
679 */
680 static int iscsi_handle_chap_i_value ( struct iscsi_session *iscsi,
681 const char *value ) {
682 unsigned int identifier;
683 char *endp;
684 int rc;
685
686 /* The CHAP identifier is an integer value */
687 identifier = strtoul ( value, &endp, 0 );
688 if ( *endp != '\0' ) {
689 DBGC ( iscsi, "iSCSI %p saw invalid CHAP identifier \"%s\"\n",
690 iscsi, value );
691 return -EPROTO;
692 }
693
694 /* Prepare for CHAP with MD5 */
695 chap_finish ( &iscsi->chap );
696 if ( ( rc = chap_init ( &iscsi->chap, &md5_algorithm ) ) != 0 ) {
697 DBGC ( iscsi, "iSCSI %p could not initialise CHAP: %s\n",
698 iscsi, strerror ( rc ) );
699 return rc;
700 }
701
702 /* Identifier and secret are the first two components of the
703 * challenge.
704 */
705 chap_set_identifier ( &iscsi->chap, identifier );
706 if ( iscsi->initiator_password ) {
707 chap_update ( &iscsi->chap, iscsi->initiator_password,
708 strlen ( iscsi->initiator_password ) );
709 }
710
711 return 0;
712 }
713
714 /**
715 * Handle iSCSI CHAP_C text value
716 *
717 * @v iscsi iSCSI session
718 * @v value CHAP_C value
719 * @ret rc Return status code
720 */
721 static int iscsi_handle_chap_c_value ( struct iscsi_session *iscsi,
722 const char *value ) {
723 char buf[3];
724 char *endp;
725 uint8_t byte;
726 unsigned int i;
727
728 /* Check and strip leading "0x" */
729 if ( ( value[0] != '0' ) || ( value[1] != 'x' ) ) {
730 DBGC ( iscsi, "iSCSI %p saw invalid CHAP challenge \"%s\"\n",
731 iscsi, value );
732 return -EPROTO;
733 }
734 value += 2;
735
736 /* Process challenge an octet at a time */
737 for ( ; ( value[0] && value[1] ) ; value += 2 ) {
738 memcpy ( buf, value, 2 );
739 buf[2] = 0;
740 byte = strtoul ( buf, &endp, 16 );
741 if ( *endp != '\0' ) {
742 DBGC ( iscsi, "iSCSI %p saw invalid CHAP challenge "
743 "byte \"%s\"\n", iscsi, buf );
744 return -EPROTO;
745 }
746 chap_update ( &iscsi->chap, &byte, sizeof ( byte ) );
747 }
748
749 /* Build CHAP response */
750 DBGC ( iscsi, "iSCSI %p sending CHAP response\n", iscsi );
751 chap_respond ( &iscsi->chap );
752 iscsi->status |= ISCSI_STATUS_STRINGS_CHAP_RESPONSE;
753
754 /* Send CHAP challenge, if applicable */
755 if ( iscsi->target_username ) {
756 iscsi->status |= ISCSI_STATUS_STRINGS_CHAP_CHALLENGE;
757 /* Generate CHAP challenge data */
758 for ( i = 0 ; i < sizeof ( iscsi->chap_challenge ) ; i++ ) {
759 iscsi->chap_challenge[i] = random();
760 }
761 }
762
763 return 0;
764 }
765
766 /**
767 * Handle iSCSI CHAP_N text value
768 *
769 * @v iscsi iSCSI session
770 * @v value CHAP_N value
771 * @ret rc Return status code
772 */
773 static int iscsi_handle_chap_n_value ( struct iscsi_session *iscsi,
774 const char *value ) {
775
776 /* The target username isn't actually involved at any point in
777 * the authentication process; it merely serves to identify
778 * which password the target is using to generate the CHAP
779 * response. We unnecessarily verify that the username is as
780 * expected, in order to provide mildly helpful diagnostics if
781 * the target is supplying the wrong username/password
782 * combination.
783 */
784 if ( iscsi->target_username &&
785 ( strcmp ( iscsi->target_username, value ) != 0 ) ) {
786 DBGC ( iscsi, "iSCSI %p target username \"%s\" incorrect "
787 "(wanted \"%s\")\n",
788 iscsi, value, iscsi->target_username );
789 return -EACCES;
790 }
791
792 return 0;
793 }
794
795 /**
796 * Handle iSCSI CHAP_R text value
797 *
798 * @v iscsi iSCSI session
799 * @v value CHAP_R value
800 * @ret rc Return status code
801 */
802 static int iscsi_handle_chap_r_value ( struct iscsi_session *iscsi,
803 const char *value ) {
804 char buf[3];
805 char *endp;
806 uint8_t byte;
807 unsigned int i;
808 int rc;
809
810 /* Generate CHAP response for verification */
811 chap_finish ( &iscsi->chap );
812 if ( ( rc = chap_init ( &iscsi->chap, &md5_algorithm ) ) != 0 ) {
813 DBGC ( iscsi, "iSCSI %p could not initialise CHAP: %s\n",
814 iscsi, strerror ( rc ) );
815 return rc;
816 }
817 chap_set_identifier ( &iscsi->chap, iscsi->chap_challenge[0] );
818 if ( iscsi->target_password ) {
819 chap_update ( &iscsi->chap, iscsi->target_password,
820 strlen ( iscsi->target_password ) );
821 }
822 chap_update ( &iscsi->chap, &iscsi->chap_challenge[1],
823 ( sizeof ( iscsi->chap_challenge ) - 1 ) );
824 chap_respond ( &iscsi->chap );
825
826 /* Check and strip leading "0x" */
827 if ( ( value[0] != '0' ) || ( value[1] != 'x' ) ) {
828 DBGC ( iscsi, "iSCSI %p saw invalid CHAP response \"%s\"\n",
829 iscsi, value );
830 return -EPROTO;
831 }
832 value += 2;
833
834 /* Check CHAP response length */
835 if ( strlen ( value ) != ( 2 * iscsi->chap.response_len ) ) {
836 DBGC ( iscsi, "iSCSI %p invalid CHAP response length\n",
837 iscsi );
838 return -EPROTO;
839 }
840
841 /* Process response an octet at a time */
842 for ( i = 0 ; ( value[0] && value[1] ) ; value += 2, i++ ) {
843 memcpy ( buf, value, 2 );
844 buf[2] = 0;
845 byte = strtoul ( buf, &endp, 16 );
846 if ( *endp != '\0' ) {
847 DBGC ( iscsi, "iSCSI %p saw invalid CHAP response "
848 "byte \"%s\"\n", iscsi, buf );
849 return -EPROTO;
850 }
851 if ( byte != iscsi->chap.response[i] ) {
852 DBGC ( iscsi, "iSCSI %p saw incorrect CHAP "
853 "response\n", iscsi );
854 return -EACCES;
855 }
856 }
857 assert ( i == iscsi->chap.response_len );
858
859 /* Mark session as authenticated */
860 iscsi->status |= ISCSI_STATUS_AUTH_REVERSE_OK;
861
862 return 0;
863 }
864
865 /** An iSCSI text string that we want to handle */
866 struct iscsi_string_type {
867 /** String key
868 *
869 * This is the portion up to and including the "=" sign,
870 * e.g. "InitiatorName=", "CHAP_A=", etc.
871 */
872 const char *key;
873 /** Handle iSCSI string value
874 *
875 * @v iscsi iSCSI session
876 * @v value iSCSI string value
877 * @ret rc Return status code
878 */
879 int ( * handle ) ( struct iscsi_session *iscsi, const char *value );
880 };
881
882 /** iSCSI text strings that we want to handle */
883 static struct iscsi_string_type iscsi_string_types[] = {
884 { "TargetAddress=", iscsi_handle_targetaddress_value },
885 { "AuthMethod=", iscsi_handle_authmethod_value },
886 { "CHAP_A=", iscsi_handle_chap_a_value },
887 { "CHAP_I=", iscsi_handle_chap_i_value },
888 { "CHAP_C=", iscsi_handle_chap_c_value },
889 { "CHAP_N=", iscsi_handle_chap_n_value },
890 { "CHAP_R=", iscsi_handle_chap_r_value },
891 { NULL, NULL }
892 };
893
894 /**
895 * Handle iSCSI string
896 *
897 * @v iscsi iSCSI session
898 * @v string iSCSI string (in "key=value" format)
899 * @ret rc Return status code
900 */
901 static int iscsi_handle_string ( struct iscsi_session *iscsi,
902 const char *string ) {
903 struct iscsi_string_type *type;
904 size_t key_len;
905 int rc;
906
907 for ( type = iscsi_string_types ; type->key ; type++ ) {
908 key_len = strlen ( type->key );
909 if ( strncmp ( string, type->key, key_len ) != 0 )
910 continue;
911 DBGC ( iscsi, "iSCSI %p handling %s\n", iscsi, string );
912 if ( ( rc = type->handle ( iscsi,
913 ( string + key_len ) ) ) != 0 ) {
914 DBGC ( iscsi, "iSCSI %p could not handle %s: %s\n",
915 iscsi, string, strerror ( rc ) );
916 return rc;
917 }
918 return 0;
919 }
920 DBGC ( iscsi, "iSCSI %p ignoring %s\n", iscsi, string );
921 return 0;
922 }
923
924 /**
925 * Handle iSCSI strings
926 *
927 * @v iscsi iSCSI session
928 * @v string iSCSI string buffer
929 * @v len Length of string buffer
930 * @ret rc Return status code
931 */
932 static int iscsi_handle_strings ( struct iscsi_session *iscsi,
933 const char *strings, size_t len ) {
934 size_t string_len;
935 int rc;
936
937 /* Handle each string in turn, taking care not to overrun the
938 * data buffer in case of badly-terminated data.
939 */
940 while ( 1 ) {
941 string_len = ( strnlen ( strings, len ) + 1 );
942 if ( string_len > len )
943 break;
944 if ( ( rc = iscsi_handle_string ( iscsi, strings ) ) != 0 )
945 return rc;
946 strings += string_len;
947 len -= string_len;
948 }
949 return 0;
950 }
951
952 /**
953 * Receive PDU data into buffer
954 *
955 * @v iscsi iSCSI session
956 * @v data Data to receive
957 * @v len Length of data
958 * @ret rc Return status code
959 *
960 * This can be used when the RX PDU type handler wishes to buffer up
961 * all received data and process the PDU as a single unit. The caller
962 * is repsonsible for calling iscsi_rx_buffered_data_done() after
963 * processing the data.
964 */
965 static int iscsi_rx_buffered_data ( struct iscsi_session *iscsi,
966 const void *data, size_t len ) {
967
968 /* Allocate buffer on first call */
969 if ( ! iscsi->rx_buffer ) {
970 iscsi->rx_buffer = malloc ( iscsi->rx_len );
971 if ( ! iscsi->rx_buffer )
972 return -ENOMEM;
973 }
974
975 /* Copy data to buffer */
976 assert ( ( iscsi->rx_offset + len ) <= iscsi->rx_len );
977 memcpy ( ( iscsi->rx_buffer + iscsi->rx_offset ), data, len );
978
979 return 0;
980 }
981
982 /**
983 * Convert iSCSI response status to return status code
984 *
985 * @v status_class iSCSI status class
986 * @v status_detail iSCSI status detail
987 * @ret rc Return status code
988 */
989 static int iscsi_status_to_rc ( unsigned int status_class,
990 unsigned int status_detail ) {
991 switch ( status_class ) {
992 case ISCSI_STATUS_INITIATOR_ERROR :
993 switch ( status_detail ) {
994 case ISCSI_STATUS_INITIATOR_ERROR_AUTHENTICATION :
995 return -EACCES;
996 case ISCSI_STATUS_INITIATOR_ERROR_AUTHORISATION :
997 return -EPERM;
998 case ISCSI_STATUS_INITIATOR_ERROR_NOT_FOUND :
999 case ISCSI_STATUS_INITIATOR_ERROR_REMOVED :
1000 return -ENODEV;
1001 default :
1002 return -ENOTSUP;
1003 }
1004 case ISCSI_STATUS_TARGET_ERROR :
1005 return -EIO;
1006 default :
1007 return -EINVAL;
1008 }
1009 }
1010
1011 /**
1012 * Receive data segment of an iSCSI login response PDU
1013 *
1014 * @v iscsi iSCSI session
1015 * @v data Received data
1016 * @v len Length of received data
1017 * @v remaining Data remaining after this data
1018 * @ret rc Return status code
1019 */
1020 static int iscsi_rx_login_response ( struct iscsi_session *iscsi,
1021 const void *data, size_t len,
1022 size_t remaining ) {
1023 struct iscsi_bhs_login_response *response
1024 = &iscsi->rx_bhs.login_response;
1025 int rc;
1026
1027 /* Buffer up the PDU data */
1028 if ( ( rc = iscsi_rx_buffered_data ( iscsi, data, len ) ) != 0 ) {
1029 DBGC ( iscsi, "iSCSI %p could not buffer login response: %s\n",
1030 iscsi, strerror ( rc ) );
1031 return rc;
1032 }
1033 if ( remaining )
1034 return 0;
1035
1036 /* Process string data and discard string buffer */
1037 if ( ( rc = iscsi_handle_strings ( iscsi, iscsi->rx_buffer,
1038 iscsi->rx_len ) ) != 0 )
1039 return rc;
1040 iscsi_rx_buffered_data_done ( iscsi );
1041
1042 /* Check for login redirection */
1043 if ( response->status_class == ISCSI_STATUS_REDIRECT ) {
1044 DBGC ( iscsi, "iSCSI %p redirecting to new server\n", iscsi );
1045 iscsi_close_connection ( iscsi, 0 );
1046 if ( ( rc = iscsi_open_connection ( iscsi ) ) != 0 ) {
1047 DBGC ( iscsi, "iSCSI %p could not redirect: %s\n ",
1048 iscsi, strerror ( rc ) );
1049 return rc;
1050 }
1051 return 0;
1052 }
1053
1054 /* Check for fatal errors */
1055 if ( response->status_class != 0 ) {
1056 DBGC ( iscsi, "iSCSI login failure: class %02x detail %02x\n",
1057 response->status_class, response->status_detail );
1058 rc = iscsi_status_to_rc ( response->status_class,
1059 response->status_detail );
1060 iscsi->instant_rc = rc;
1061 return rc;
1062 }
1063
1064 /* Handle login transitions */
1065 if ( response->flags & ISCSI_LOGIN_FLAG_TRANSITION ) {
1066 iscsi->status &= ~( ISCSI_STATUS_PHASE_MASK |
1067 ISCSI_STATUS_STRINGS_MASK );
1068 switch ( response->flags & ISCSI_LOGIN_NSG_MASK ) {
1069 case ISCSI_LOGIN_NSG_OPERATIONAL_NEGOTIATION:
1070 iscsi->status |=
1071 ( ISCSI_STATUS_OPERATIONAL_NEGOTIATION_PHASE |
1072 ISCSI_STATUS_STRINGS_OPERATIONAL );
1073 break;
1074 case ISCSI_LOGIN_NSG_FULL_FEATURE_PHASE:
1075 iscsi->status |= ISCSI_STATUS_FULL_FEATURE_PHASE;
1076 break;
1077 default:
1078 DBGC ( iscsi, "iSCSI %p got invalid response flags "
1079 "%02x\n", iscsi, response->flags );
1080 return -EIO;
1081 }
1082 }
1083
1084 /* Send next login request PDU if we haven't reached the full
1085 * feature phase yet.
1086 */
1087 if ( ( iscsi->status & ISCSI_STATUS_PHASE_MASK ) !=
1088 ISCSI_STATUS_FULL_FEATURE_PHASE ) {
1089 iscsi_start_login ( iscsi );
1090 return 0;
1091 }
1092
1093 /* Check that target authentication was successful (if required) */
1094 if ( ( iscsi->status & ISCSI_STATUS_AUTH_REVERSE_REQUIRED ) &&
1095 ! ( iscsi->status & ISCSI_STATUS_AUTH_REVERSE_OK ) ) {
1096 DBGC ( iscsi, "iSCSI %p nefarious target tried to bypass "
1097 "authentication\n", iscsi );
1098 return -EPROTO;
1099 }
1100
1101 /* Reset retry count */
1102 iscsi->retry_count = 0;
1103
1104 /* Record TSIH for future reference */
1105 iscsi->tsih = ntohl ( response->tsih );
1106
1107 /* Send the actual SCSI command */
1108 iscsi_start_command ( iscsi );
1109
1110 return 0;
1111 }
1112
1113 /****************************************************************************
1114 *
1115 * iSCSI to socket interface
1116 *
1117 */
1118
1119 /**
1120 * Start up a new TX PDU
1121 *
1122 * @v iscsi iSCSI session
1123 *
1124 * This initiates the process of sending a new PDU. Only one PDU may
1125 * be in transit at any one time.
1126 */
1127 static void iscsi_start_tx ( struct iscsi_session *iscsi ) {
1128 assert ( iscsi->tx_state == ISCSI_TX_IDLE );
1129
1130 /* Initialise TX BHS */
1131 memset ( &iscsi->tx_bhs, 0, sizeof ( iscsi->tx_bhs ) );
1132
1133 /* Flag TX engine to start transmitting */
1134 iscsi->tx_state = ISCSI_TX_BHS;
1135 }
1136
1137 /**
1138 * Transmit nothing
1139 *
1140 * @v iscsi iSCSI session
1141 * @ret rc Return status code
1142 */
1143 static int iscsi_tx_nothing ( struct iscsi_session *iscsi __unused ) {
1144 return 0;
1145 }
1146
1147 /**
1148 * Transmit basic header segment of an iSCSI PDU
1149 *
1150 * @v iscsi iSCSI session
1151 * @ret rc Return status code
1152 */
1153 static int iscsi_tx_bhs ( struct iscsi_session *iscsi ) {
1154 return xfer_deliver_raw ( &iscsi->socket, &iscsi->tx_bhs,
1155 sizeof ( iscsi->tx_bhs ) );
1156 }
1157
1158 /**
1159 * Transmit data segment of an iSCSI PDU
1160 *
1161 * @v iscsi iSCSI session
1162 * @ret rc Return status code
1163 *
1164 * Handle transmission of part of a PDU data segment. iscsi::tx_bhs
1165 * will be valid when this is called.
1166 */
1167 static int iscsi_tx_data ( struct iscsi_session *iscsi ) {
1168 struct iscsi_bhs_common *common = &iscsi->tx_bhs.common;
1169
1170 switch ( common->opcode & ISCSI_OPCODE_MASK ) {
1171 case ISCSI_OPCODE_DATA_OUT:
1172 return iscsi_tx_data_out ( iscsi );
1173 case ISCSI_OPCODE_LOGIN_REQUEST:
1174 return iscsi_tx_login_request ( iscsi );
1175 default:
1176 /* Nothing to send in other states */
1177 return 0;
1178 }
1179 }
1180
1181 /**
1182 * Transmit data padding of an iSCSI PDU
1183 *
1184 * @v iscsi iSCSI session
1185 * @ret rc Return status code
1186 *
1187 * Handle transmission of any data padding in a PDU data segment.
1188 * iscsi::tx_bhs will be valid when this is called.
1189 */
1190 static int iscsi_tx_data_padding ( struct iscsi_session *iscsi ) {
1191 static const char pad[] = { '\0', '\0', '\0' };
1192 struct iscsi_bhs_common *common = &iscsi->tx_bhs.common;
1193 size_t pad_len;
1194
1195 pad_len = ISCSI_DATA_PAD_LEN ( common->lengths );
1196 if ( ! pad_len )
1197 return 0;
1198
1199 return xfer_deliver_raw ( &iscsi->socket, pad, pad_len );
1200 }
1201
1202 /**
1203 * Complete iSCSI PDU transmission
1204 *
1205 * @v iscsi iSCSI session
1206 *
1207 * Called when a PDU has been completely transmitted and the TX state
1208 * machine is about to enter the idle state. iscsi::tx_bhs will be
1209 * valid for the just-completed PDU when this is called.
1210 */
1211 static void iscsi_tx_done ( struct iscsi_session *iscsi ) {
1212 struct iscsi_bhs_common *common = &iscsi->tx_bhs.common;
1213
1214 switch ( common->opcode & ISCSI_OPCODE_MASK ) {
1215 case ISCSI_OPCODE_DATA_OUT:
1216 iscsi_data_out_done ( iscsi );
1217 case ISCSI_OPCODE_LOGIN_REQUEST:
1218 iscsi_login_request_done ( iscsi );
1219 default:
1220 /* No action */
1221 break;
1222 }
1223 }
1224
1225 /**
1226 * Transmit iSCSI PDU
1227 *
1228 * @v iscsi iSCSI session
1229 * @v buf Temporary data buffer
1230 * @v len Length of temporary data buffer
1231 *
1232 * Constructs data to be sent for the current TX state
1233 */
1234 static void iscsi_tx_step ( struct process *process ) {
1235 struct iscsi_session *iscsi =
1236 container_of ( process, struct iscsi_session, process );
1237 struct iscsi_bhs_common *common = &iscsi->tx_bhs.common;
1238 int ( * tx ) ( struct iscsi_session *iscsi );
1239 enum iscsi_tx_state next_state;
1240 size_t tx_len;
1241 int rc;
1242
1243 /* Select fragment to transmit */
1244 while ( 1 ) {
1245 switch ( iscsi->tx_state ) {
1246 case ISCSI_TX_IDLE:
1247 /* Stop processing */
1248 return;
1249 case ISCSI_TX_BHS:
1250 tx = iscsi_tx_bhs;
1251 tx_len = sizeof ( iscsi->tx_bhs );
1252 next_state = ISCSI_TX_AHS;
1253 break;
1254 case ISCSI_TX_AHS:
1255 tx = iscsi_tx_nothing;
1256 tx_len = 0;
1257 next_state = ISCSI_TX_DATA;
1258 break;
1259 case ISCSI_TX_DATA:
1260 tx = iscsi_tx_data;
1261 tx_len = ISCSI_DATA_LEN ( common->lengths );
1262 next_state = ISCSI_TX_DATA_PADDING;
1263 break;
1264 case ISCSI_TX_DATA_PADDING:
1265 tx = iscsi_tx_data_padding;
1266 tx_len = ISCSI_DATA_PAD_LEN ( common->lengths );
1267 next_state = ISCSI_TX_IDLE;
1268 break;
1269 default:
1270 assert ( 0 );
1271 return;
1272 }
1273
1274 /* Check for window availability, if needed */
1275 if ( tx_len && ( xfer_window ( &iscsi->socket ) == 0 ) ) {
1276 /* Cannot transmit at this point; stop processing */
1277 return;
1278 }
1279
1280 /* Transmit data */
1281 if ( ( rc = tx ( iscsi ) ) != 0 ) {
1282 DBGC ( iscsi, "iSCSI %p could not transmit: %s\n",
1283 iscsi, strerror ( rc ) );
1284 return;
1285 }
1286
1287 /* Move to next state */
1288 iscsi->tx_state = next_state;
1289 if ( next_state == ISCSI_TX_IDLE )
1290 iscsi_tx_done ( iscsi );
1291 }
1292 }
1293
1294 /**
1295 * Receive basic header segment of an iSCSI PDU
1296 *
1297 * @v iscsi iSCSI session
1298 * @v data Received data
1299 * @v len Length of received data
1300 * @v remaining Data remaining after this data
1301 * @ret rc Return status code
1302 *
1303 * This fills in iscsi::rx_bhs with the data from the BHS portion of
1304 * the received PDU.
1305 */
1306 static int iscsi_rx_bhs ( struct iscsi_session *iscsi, const void *data,
1307 size_t len, size_t remaining __unused ) {
1308 memcpy ( &iscsi->rx_bhs.bytes[iscsi->rx_offset], data, len );
1309 if ( ( iscsi->rx_offset + len ) >= sizeof ( iscsi->rx_bhs ) ) {
1310 DBGC2 ( iscsi, "iSCSI %p received PDU opcode %#x len %#x\n",
1311 iscsi, iscsi->rx_bhs.common.opcode,
1312 ISCSI_DATA_LEN ( iscsi->rx_bhs.common.lengths ) );
1313 }
1314 return 0;
1315 }
1316
1317 /**
1318 * Discard portion of an iSCSI PDU.
1319 *
1320 * @v iscsi iSCSI session
1321 * @v data Received data
1322 * @v len Length of received data
1323 * @v remaining Data remaining after this data
1324 * @ret rc Return status code
1325 *
1326 * This discards data from a portion of a received PDU.
1327 */
1328 static int iscsi_rx_discard ( struct iscsi_session *iscsi __unused,
1329 const void *data __unused, size_t len __unused,
1330 size_t remaining __unused ) {
1331 /* Do nothing */
1332 return 0;
1333 }
1334
1335 /**
1336 * Receive data segment of an iSCSI PDU
1337 *
1338 * @v iscsi iSCSI session
1339 * @v data Received data
1340 * @v len Length of received data
1341 * @v remaining Data remaining after this data
1342 * @ret rc Return status code
1343 *
1344 * Handle processing of part of a PDU data segment. iscsi::rx_bhs
1345 * will be valid when this is called.
1346 */
1347 static int iscsi_rx_data ( struct iscsi_session *iscsi, const void *data,
1348 size_t len, size_t remaining ) {
1349 struct iscsi_bhs_common_response *response
1350 = &iscsi->rx_bhs.common_response;
1351
1352 /* Update cmdsn and statsn */
1353 iscsi->cmdsn = ntohl ( response->expcmdsn );
1354 iscsi->statsn = ntohl ( response->statsn );
1355
1356 switch ( response->opcode & ISCSI_OPCODE_MASK ) {
1357 case ISCSI_OPCODE_LOGIN_RESPONSE:
1358 return iscsi_rx_login_response ( iscsi, data, len, remaining );
1359 case ISCSI_OPCODE_SCSI_RESPONSE:
1360 return iscsi_rx_scsi_response ( iscsi, data, len, remaining );
1361 case ISCSI_OPCODE_DATA_IN:
1362 return iscsi_rx_data_in ( iscsi, data, len, remaining );
1363 case ISCSI_OPCODE_R2T:
1364 return iscsi_rx_r2t ( iscsi, data, len, remaining );
1365 default:
1366 if ( remaining )
1367 return 0;
1368 DBGC ( iscsi, "iSCSI %p unknown opcode %02x\n", iscsi,
1369 response->opcode );
1370 return -ENOTSUP;
1371 }
1372 }
1373
1374 /**
1375 * Receive new data
1376 *
1377 * @v socket Transport layer interface
1378 * @v data Received data
1379 * @v len Length of received data
1380 * @ret rc Return status code
1381 *
1382 * This handles received PDUs. The receive strategy is to fill in
1383 * iscsi::rx_bhs with the contents of the BHS portion of the PDU,
1384 * throw away any AHS portion, and then process each part of the data
1385 * portion as it arrives. The data processing routine therefore
1386 * always has a full copy of the BHS available, even for portions of
1387 * the data in different packets to the BHS.
1388 */
1389 static int iscsi_socket_deliver_raw ( struct xfer_interface *socket,
1390 const void *data, size_t len ) {
1391 struct iscsi_session *iscsi =
1392 container_of ( socket, struct iscsi_session, socket );
1393 struct iscsi_bhs_common *common = &iscsi->rx_bhs.common;
1394 int ( * rx ) ( struct iscsi_session *iscsi, const void *data,
1395 size_t len, size_t remaining );
1396 enum iscsi_rx_state next_state;
1397 size_t frag_len;
1398 size_t remaining;
1399 int rc;
1400
1401 while ( 1 ) {
1402 switch ( iscsi->rx_state ) {
1403 case ISCSI_RX_BHS:
1404 rx = iscsi_rx_bhs;
1405 iscsi->rx_len = sizeof ( iscsi->rx_bhs );
1406 next_state = ISCSI_RX_AHS;
1407 break;
1408 case ISCSI_RX_AHS:
1409 rx = iscsi_rx_discard;
1410 iscsi->rx_len = 4 * ISCSI_AHS_LEN ( common->lengths );
1411 next_state = ISCSI_RX_DATA;
1412 break;
1413 case ISCSI_RX_DATA:
1414 rx = iscsi_rx_data;
1415 iscsi->rx_len = ISCSI_DATA_LEN ( common->lengths );
1416 next_state = ISCSI_RX_DATA_PADDING;
1417 break;
1418 case ISCSI_RX_DATA_PADDING:
1419 rx = iscsi_rx_discard;
1420 iscsi->rx_len = ISCSI_DATA_PAD_LEN ( common->lengths );
1421 next_state = ISCSI_RX_BHS;
1422 break;
1423 default:
1424 assert ( 0 );
1425 return -EINVAL;
1426 }
1427
1428 frag_len = iscsi->rx_len - iscsi->rx_offset;
1429 if ( frag_len > len )
1430 frag_len = len;
1431 remaining = iscsi->rx_len - iscsi->rx_offset - frag_len;
1432 if ( ( rc = rx ( iscsi, data, frag_len, remaining ) ) != 0 ) {
1433 DBGC ( iscsi, "iSCSI %p could not process received "
1434 "data: %s\n", iscsi, strerror ( rc ) );
1435 iscsi_close_connection ( iscsi, rc );
1436 iscsi_scsi_done ( iscsi, rc );
1437 return rc;
1438 }
1439
1440 iscsi->rx_offset += frag_len;
1441 data += frag_len;
1442 len -= frag_len;
1443
1444 /* If all the data for this state has not yet been
1445 * received, stay in this state for now.
1446 */
1447 if ( iscsi->rx_offset != iscsi->rx_len )
1448 return 0;
1449
1450 iscsi->rx_state = next_state;
1451 iscsi->rx_offset = 0;
1452 }
1453
1454 return 0;
1455 }
1456
1457 /**
1458 * Handle stream connection closure
1459 *
1460 * @v socket Transport layer interface
1461 * @v rc Reason for close
1462 *
1463 */
1464 static void iscsi_socket_close ( struct xfer_interface *socket, int rc ) {
1465 struct iscsi_session *iscsi =
1466 container_of ( socket, struct iscsi_session, socket );
1467
1468 /* Even a graceful close counts as an error for iSCSI */
1469 if ( ! rc )
1470 rc = -ECONNRESET;
1471
1472 /* Close session cleanly */
1473 iscsi_close_connection ( iscsi, rc );
1474
1475 /* Retry connection if within the retry limit, otherwise fail */
1476 if ( ++iscsi->retry_count <= ISCSI_MAX_RETRIES ) {
1477 DBGC ( iscsi, "iSCSI %p retrying connection (retry #%d)\n",
1478 iscsi, iscsi->retry_count );
1479 if ( ( rc = iscsi_open_connection ( iscsi ) ) != 0 ) {
1480 DBGC ( iscsi, "iSCSI %p could not reconnect: %s\n",
1481 iscsi, strerror ( rc ) );
1482 iscsi_scsi_done ( iscsi, rc );
1483 }
1484 } else {
1485 DBGC ( iscsi, "iSCSI %p retry count exceeded\n", iscsi );
1486 iscsi->instant_rc = rc;
1487 iscsi_scsi_done ( iscsi, rc );
1488 }
1489 }
1490
1491 /**
1492 * Handle redirection event
1493 *
1494 * @v socket Transport layer interface
1495 * @v type Location type
1496 * @v args Remaining arguments depend upon location type
1497 * @ret rc Return status code
1498 */
1499 static int iscsi_vredirect ( struct xfer_interface *socket, int type,
1500 va_list args ) {
1501 struct iscsi_session *iscsi =
1502 container_of ( socket, struct iscsi_session, socket );
1503 va_list tmp;
1504 struct sockaddr *peer;
1505
1506 /* Intercept redirects to a LOCATION_SOCKET and record the IP
1507 * address for the iBFT. This is a bit of a hack, but avoids
1508 * inventing an ioctl()-style call to retrieve the socket
1509 * address from a data-xfer interface.
1510 */
1511 if ( type == LOCATION_SOCKET ) {
1512 va_copy ( tmp, args );
1513 ( void ) va_arg ( tmp, int ); /* Discard "semantics" */
1514 peer = va_arg ( tmp, struct sockaddr * );
1515 memcpy ( &iscsi->target_sockaddr, peer,
1516 sizeof ( iscsi->target_sockaddr ) );
1517 va_end ( tmp );
1518 }
1519
1520 return xfer_vreopen ( socket, type, args );
1521 }
1522
1523
1524 /** iSCSI socket operations */
1525 static struct xfer_interface_operations iscsi_socket_operations = {
1526 .close = iscsi_socket_close,
1527 .vredirect = iscsi_vredirect,
1528 .window = unlimited_xfer_window,
1529 .alloc_iob = default_xfer_alloc_iob,
1530 .deliver_iob = xfer_deliver_as_raw,
1531 .deliver_raw = iscsi_socket_deliver_raw,
1532 };
1533
1534
1535 /****************************************************************************
1536 *
1537 * iSCSI command issuing
1538 *
1539 */
1540
1541 /**
1542 * Issue SCSI command
1543 *
1544 * @v scsi SCSI device
1545 * @v command SCSI command
1546 * @ret rc Return status code
1547 */
1548 static int iscsi_command ( struct scsi_device *scsi,
1549 struct scsi_command *command ) {
1550 struct iscsi_session *iscsi =
1551 container_of ( scsi->backend, struct iscsi_session, refcnt );
1552 int rc;
1553
1554 /* Abort immediately if we have a recorded permanent failure */
1555 if ( iscsi->instant_rc )
1556 return iscsi->instant_rc;
1557
1558 /* Record SCSI command */
1559 iscsi->command = command;
1560
1561 /* Issue command or open connection as appropriate */
1562 if ( iscsi->status ) {
1563 iscsi_start_command ( iscsi );
1564 } else {
1565 if ( ( rc = iscsi_open_connection ( iscsi ) ) != 0 ) {
1566 iscsi->command = NULL;
1567 return rc;
1568 }
1569 }
1570
1571 return 0;
1572 }
1573
1574 /**
1575 * Shut down iSCSI interface
1576 *
1577 * @v scsi SCSI device
1578 */
1579 void iscsi_detach ( struct scsi_device *scsi ) {
1580 struct iscsi_session *iscsi =
1581 container_of ( scsi->backend, struct iscsi_session, refcnt );
1582
1583 xfer_nullify ( &iscsi->socket );
1584 iscsi_close_connection ( iscsi, 0 );
1585 process_del ( &iscsi->process );
1586 scsi->command = scsi_detached_command;
1587 ref_put ( scsi->backend );
1588 scsi->backend = NULL;
1589 }
1590
1591 /****************************************************************************
1592 *
1593 * Instantiator
1594 *
1595 */
1596
1597 /** iSCSI root path components (as per RFC4173) */
1598 enum iscsi_root_path_component {
1599 RP_LITERAL = 0,
1600 RP_SERVERNAME,
1601 RP_PROTOCOL,
1602 RP_PORT,
1603 RP_LUN,
1604 RP_TARGETNAME,
1605 NUM_RP_COMPONENTS
1606 };
1607
1608 /**
1609 * Parse iSCSI root path
1610 *
1611 * @v iscsi iSCSI session
1612 * @v root_path iSCSI root path (as per RFC4173)
1613 * @ret rc Return status code
1614 */
1615 static int iscsi_parse_root_path ( struct iscsi_session *iscsi,
1616 const char *root_path ) {
1617 char rp_copy[ strlen ( root_path ) + 1 ];
1618 char *rp_comp[NUM_RP_COMPONENTS];
1619 char *rp = rp_copy;
1620 int i = 0;
1621 int rc;
1622
1623 /* Split root path into component parts */
1624 strcpy ( rp_copy, root_path );
1625 while ( 1 ) {
1626 rp_comp[i++] = rp;
1627 if ( i == NUM_RP_COMPONENTS )
1628 break;
1629 for ( ; *rp != ':' ; rp++ ) {
1630 if ( ! *rp ) {
1631 DBGC ( iscsi, "iSCSI %p root path \"%s\" "
1632 "too short\n", iscsi, root_path );
1633 return -EINVAL;
1634 }
1635 }
1636 *(rp++) = '\0';
1637 }
1638
1639 /* Use root path components to configure iSCSI session */
1640 iscsi->target_address = strdup ( rp_comp[RP_SERVERNAME] );
1641 if ( ! iscsi->target_address )
1642 return -ENOMEM;
1643 iscsi->target_port = strtoul ( rp_comp[RP_PORT], NULL, 10 );
1644 if ( ! iscsi->target_port )
1645 iscsi->target_port = ISCSI_PORT;
1646 if ( ( rc = scsi_parse_lun ( rp_comp[RP_LUN], &iscsi->lun ) ) != 0 ) {
1647 DBGC ( iscsi, "iSCSI %p invalid LUN \"%s\"\n",
1648 iscsi, rp_comp[RP_LUN] );
1649 return rc;
1650 }
1651 iscsi->target_iqn = strdup ( rp_comp[RP_TARGETNAME] );
1652 if ( ! iscsi->target_iqn )
1653 return -ENOMEM;
1654
1655 return 0;
1656 }
1657
1658 /**
1659 * Set iSCSI authentication details
1660 *
1661 * @v iscsi iSCSI session
1662 * @v initiator_username Initiator username, if any
1663 * @v initiator_password Initiator password, if any
1664 * @v target_username Target username, if any
1665 * @v target_password Target password, if any
1666 * @ret rc Return status code
1667 */
1668 static int iscsi_set_auth ( struct iscsi_session *iscsi,
1669 const char *initiator_username,
1670 const char *initiator_password,
1671 const char *target_username,
1672 const char *target_password ) {
1673
1674 /* Check for initiator or target credentials */
1675 if ( initiator_username || initiator_password ||
1676 target_username || target_password ) {
1677
1678 /* We must have at least an initiator username+password */
1679 if ( ! ( initiator_username && initiator_password ) )
1680 goto invalid_auth;
1681
1682 /* Store initiator credentials */
1683 iscsi->initiator_username = strdup ( initiator_username );
1684 if ( ! iscsi->initiator_username )
1685 return -ENOMEM;
1686 iscsi->initiator_password = strdup ( initiator_password );
1687 if ( ! iscsi->initiator_password )
1688 return -ENOMEM;
1689
1690 /* Check for target credentials */
1691 if ( target_username || target_password ) {
1692
1693 /* We must have target username+password */
1694 if ( ! ( target_username && target_password ) )
1695 goto invalid_auth;
1696
1697 /* Store target credentials */
1698 iscsi->target_username = strdup ( target_username );
1699 if ( ! iscsi->target_username )
1700 return -ENOMEM;
1701 iscsi->target_password = strdup ( target_password );
1702 if ( ! iscsi->target_password )
1703 return -ENOMEM;
1704 }
1705 }
1706
1707 return 0;
1708
1709 invalid_auth:
1710 DBGC ( iscsi, "iSCSI %p invalid credentials: initiator "
1711 "%sname,%spw, target %sname,%spw\n", iscsi,
1712 ( initiator_username ? "" : "no " ),
1713 ( initiator_password ? "" : "no " ),
1714 ( target_username ? "" : "no " ),
1715 ( target_password ? "" : "no " ) );
1716 return -EINVAL;
1717 }
1718
1719 /**
1720 * Attach iSCSI interface
1721 *
1722 * @v scsi SCSI device
1723 * @v root_path iSCSI root path (as per RFC4173)
1724 * @ret rc Return status code
1725 */
1726 int iscsi_attach ( struct scsi_device *scsi, const char *root_path ) {
1727 struct iscsi_session *iscsi;
1728 int rc;
1729
1730 /* Allocate and initialise structure */
1731 iscsi = zalloc ( sizeof ( *iscsi ) );
1732 if ( ! iscsi )
1733 return -ENOMEM;
1734 iscsi->refcnt.free = iscsi_free;
1735 xfer_init ( &iscsi->socket, &iscsi_socket_operations, &iscsi->refcnt );
1736 process_init ( &iscsi->process, iscsi_tx_step, &iscsi->refcnt );
1737
1738 /* Parse root path */
1739 if ( ( rc = iscsi_parse_root_path ( iscsi, root_path ) ) != 0 )
1740 goto err;
1741 /* Set fields not specified by root path */
1742 if ( ( rc = iscsi_set_auth ( iscsi,
1743 iscsi_initiator_username,
1744 iscsi_initiator_password,
1745 iscsi_target_username,
1746 iscsi_target_password ) ) != 0 )
1747 goto err;
1748
1749 /* Sanity checks */
1750 if ( ! iscsi->target_address ) {
1751 DBGC ( iscsi, "iSCSI %p does not yet support discovery\n",
1752 iscsi );
1753 rc = -ENOTSUP;
1754 goto err;
1755 }
1756 if ( ! iscsi->target_iqn ) {
1757 DBGC ( iscsi, "iSCSI %p no target address supplied in %s\n",
1758 iscsi, root_path );
1759 rc = -EINVAL;
1760 goto err;
1761 }
1762
1763 /* Attach parent interface, mortalise self, and return */
1764 scsi->backend = ref_get ( &iscsi->refcnt );
1765 scsi->command = iscsi_command;
1766 ref_put ( &iscsi->refcnt );
1767 return 0;
1768
1769 err:
1770 ref_put ( &iscsi->refcnt );
1771 return rc;
1772 }
1773
1774 /****************************************************************************
1775 *
1776 * Settings
1777 *
1778 */
1779
1780 /** iSCSI initiator IQN setting */
1781 struct setting initiator_iqn_setting __setting = {
1782 .name = "initiator-iqn",
1783 .description = "iSCSI initiator name",
1784 .tag = DHCP_ISCSI_INITIATOR_IQN,
1785 .type = &setting_type_string,
1786 };
1787
1788 /** iSCSI reverse username setting */
1789 struct setting reverse_username_setting __setting = {
1790 .name = "reverse-username",
1791 .description = "Reverse user name",
1792 .tag = DHCP_EB_REVERSE_USERNAME,
1793 .type = &setting_type_string,
1794 };
1795
1796 /** iSCSI reverse password setting */
1797 struct setting reverse_password_setting __setting = {
1798 .name = "reverse-password",
1799 .description = "Reverse password",
1800 .tag = DHCP_EB_REVERSE_PASSWORD,
1801 .type = &setting_type_string,
1802 };
1803
1804 /** An iSCSI string setting */
1805 struct iscsi_string_setting {
1806 /** Setting */
1807 struct setting *setting;
1808 /** String to update */
1809 char **string;
1810 /** String prefix */
1811 const char *prefix;
1812 };
1813
1814 /** iSCSI string settings */
1815 static struct iscsi_string_setting iscsi_string_settings[] = {
1816 {
1817 .setting = &initiator_iqn_setting,
1818 .string = &iscsi_explicit_initiator_iqn,
1819 .prefix = "",
1820 },
1821 {
1822 .setting = &username_setting,
1823 .string = &iscsi_initiator_username,
1824 .prefix = "",
1825 },
1826 {
1827 .setting = &password_setting,
1828 .string = &iscsi_initiator_password,
1829 .prefix = "",
1830 },
1831 {
1832 .setting = &reverse_username_setting,
1833 .string = &iscsi_target_username,
1834 .prefix = "",
1835 },
1836 {
1837 .setting = &reverse_password_setting,
1838 .string = &iscsi_target_password,
1839 .prefix = "",
1840 },
1841 {
1842 .setting = &hostname_setting,
1843 .string = &iscsi_default_initiator_iqn,
1844 .prefix = "iqn.2000-01.org.etherboot:",
1845 },
1846 };
1847
1848 /**
1849 * Apply iSCSI setting
1850 *
1851 * @v setting iSCSI string setting
1852 * @ret rc Return status code
1853 */
1854 static int apply_iscsi_string_setting ( struct iscsi_string_setting *setting ){
1855 size_t prefix_len;
1856 int setting_len;
1857 size_t len;
1858 int check_len;
1859 char *p;
1860
1861 /* Free old string */
1862 free ( *setting->string );
1863 *setting->string = NULL;
1864
1865 /* Allocate new string */
1866 prefix_len = strlen ( setting->prefix );
1867 setting_len = fetch_setting_len ( NULL, setting->setting );
1868 if ( setting_len < 0 ) {
1869 /* Missing settings are not errors; leave strings as NULL */
1870 return 0;
1871 }
1872 len = ( prefix_len + setting_len + 1 );
1873 p = *setting->string = malloc ( len );
1874 if ( ! p )
1875 return -ENOMEM;
1876
1877 /* Fill new string */
1878 strcpy ( p, setting->prefix );
1879 check_len = fetch_string_setting ( NULL, setting->setting,
1880 ( p + prefix_len ),
1881 ( len - prefix_len ) );
1882 assert ( check_len == setting_len );
1883
1884 return 0;
1885 }
1886
1887 /**
1888 * Apply iSCSI settings
1889 *
1890 * @ret rc Return status code
1891 */
1892 static int apply_iscsi_settings ( void ) {
1893 struct iscsi_string_setting *setting;
1894 unsigned int i;
1895 int rc;
1896
1897 for ( i = 0 ; i < ( sizeof ( iscsi_string_settings ) /
1898 sizeof ( iscsi_string_settings[0] ) ) ; i++ ) {
1899 setting = &iscsi_string_settings[i];
1900 if ( ( rc = apply_iscsi_string_setting ( setting ) ) != 0 ) {
1901 DBG ( "iSCSI could not apply setting %s\n",
1902 setting->setting->name );
1903 return rc;
1904 }
1905 }
1906
1907 return 0;
1908 }
1909
1910 /** iSCSI settings applicator */
1911 struct settings_applicator iscsi_settings_applicator __settings_applicator = {
1912 .apply = apply_iscsi_settings,
1913 };
1914
1915 /****************************************************************************
1916 *
1917 * Initiator name
1918 *
1919 */
1920
1921 /**
1922 * Get iSCSI initiator IQN
1923 *
1924 * @v iscsi iSCSI session
1925 * @ret rc Return status code
1926 */
1927 const char * iscsi_initiator_iqn ( void ) {
1928
1929 if ( iscsi_explicit_initiator_iqn )
1930 return iscsi_explicit_initiator_iqn;
1931 if ( iscsi_default_initiator_iqn )
1932 return iscsi_default_initiator_iqn;
1933 return "iqn.2000-09.org.etherboot:UNKNOWN";
1934 }