xref: /netbsd-src/sys/dev/iscsi/iscsi_rcv.c (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1 /*	$NetBSD: iscsi_rcv.c,v 1.1 2011/10/23 21:15:02 agc Exp $	*/
2 
3 /*-
4  * Copyright (c) 2004,2005,2006,2011 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Wasabi Systems, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include "iscsi_globals.h"
32 
33 #include <sys/file.h>
34 #include <sys/socket.h>
35 #include <sys/socketvar.h>
36 
37 /*****************************************************************************/
38 
39 /*
40  * my_soo_read:
41  *    Replacement for soo_read with flag handling.
42  *
43  *    Parameter:
44  *          conn     The connection
45  *          u        The uio descriptor
46  *          flags    Read flags
47  *
48  *    Returns:    0 on success, else 1
49  */
50 
51 STATIC int
52 my_soo_read(connection_t *conn, struct uio *u, int flags)
53 {
54 	struct socket *so = (struct socket *) conn->sock->f_data;
55 	int ret;
56 #ifdef ISCSI_DEBUG
57 	size_t resid = u->uio_resid;
58 #endif
59 
60 	DEBC(conn, 99, ("soo_read req: %zu\n", resid));
61 
62 	ret = soreceive(so, NULL, u, NULL, NULL, &flags);
63 
64 	if (ret || (flags != MSG_DONTWAIT && u->uio_resid)) {
65 		DEBC(conn, 1, ("Read failed (ret: %d, req: %zu, out: %zu)\n", ret, resid,
66 				u->uio_resid));
67 		handle_connection_error(conn, ISCSI_STATUS_SOCKET_ERROR,
68 								RECOVER_CONNECTION);
69 		return 1;
70 	}
71 	return 0;
72 }
73 
74 
75 /*
76  * try_resynch_receive:
77  *    Skip over everything in the socket's receive buffer, in the hope of
78  *    ending up at the start of a new PDU.
79  *
80  *    Parameter:
81  *          conn     The connection
82  */
83 
84 STATIC void
85 try_resynch_receive(connection_t *conn)
86 {
87 	uint8_t buffer[64];
88 	struct uio uio;
89 	struct iovec io_vec;
90 	int rc;
91 
92 	uio.uio_rw = UIO_READ;
93 #if (__NetBSD_Version__ >= 399000900)
94 	UIO_SETUP_SYSSPACE(&uio);
95 #else
96 	uio.uio_segflg = UIO_SYSSPACE;
97 #endif
98 
99 	do {
100 		io_vec.iov_base = buffer;
101 		uio.uio_iov = &io_vec;
102 		uio.uio_iovcnt = 1;
103 		uio.uio_resid = io_vec.iov_len = sizeof(buffer);
104 
105 		rc = my_soo_read(conn, &uio, MSG_DONTWAIT);
106 		DEBC(conn, 9, ("try_resynch_receive: rc = %d, resid = %zu\n",
107 				rc, uio.uio_resid));
108 	} while (!rc && !uio.uio_resid);
109 }
110 
111 
112 /*
113  * ccb_from_itt
114  *    Translate ITT into CCB pointer.
115  *
116  *    Parameter:
117  *          conn     The connection
118  *          itt      The Initiator Task Tag
119  *
120  *    Returns:
121  *          Pointer to CCB, or NULL if ITT is not a valid CCB index.
122  */
123 
124 STATIC ccb_t *
125 ccb_from_itt(connection_t *conn, uint32_t itt)
126 {
127 	ccb_t *ccb;
128 	int cidx;
129 
130 	cidx = itt & 0xff;
131 	if (cidx >= CCBS_PER_SESSION) {
132 		return NULL;
133 	}
134 	ccb = &conn->session->ccb[cidx];
135 	if (ccb->ITT != itt || ccb->disp <= CCBDISP_BUSY) {
136 		return NULL;
137 	}
138 	return ccb;
139 }
140 
141 
142 /*
143  * read_pdu_data:
144  *    Initialize the uio structure for receiving everything after the
145  *    header, including data (if present), and padding. Read the data.
146  *
147  *    Parameter:
148  *          pdu      The PDU
149  *          data     Pointer to data (may be NULL for auto-allocation)
150  *          offset   The offset into the data pointer
151  *
152  *    Returns:     0 on success
153  *                 1 if an error occurs during read
154  *                -1 if the data digest was incorrect (PDU must be ignored)
155  */
156 
157 STATIC int
158 read_pdu_data(pdu_t *pdu, uint8_t *data, uint32_t offset)
159 {
160 	static uint8_t pad_bytes[4];
161 	uint32_t len, digest;
162 	struct uio *uio;
163 	int i, pad;
164 	connection_t *conn = pdu->connection;
165 
166 	if (!(len = ntoh3(pdu->pdu.DataSegmentLength))) {
167 		return 0;
168 	}
169 	pad = len & 0x03;
170 	if (pad) {
171 		pad = 4 - pad;
172 	}
173 	assert((data != NULL) || (offset == 0));
174 
175 	if (data == NULL) {
176 		/*
177 		 * NOTE: Always allocate 2 extra bytes when reading temp data,
178 		 * since temp data is mostly used for received text, and we can
179 		 * make sure there's a double zero at the end of the data to mark EOF.
180 		 */
181 		if ((data = (uint8_t *) malloc(len + 2, M_TEMP, M_WAITOK)) == NULL) {
182 			DEBOUT(("ran out of mem on receive\n"));
183 			handle_connection_error(pdu->connection,
184 				ISCSI_STATUS_NO_RESOURCES, LOGOUT_SESSION);
185 			return 1;
186 		}
187 		pdu->temp_data = data;
188 		pdu->temp_data_len = len;
189 	}
190 
191 	pdu->io_vec[0].iov_base = data + offset;
192 	pdu->io_vec[0].iov_len = len;
193 
194 	uio = &pdu->uio;
195 
196 	uio->uio_iov = pdu->io_vec;
197 	uio->uio_iovcnt = 1;
198 	uio->uio_rw = UIO_READ;
199 	uio->uio_resid = len;
200 #if (__NetBSD_Version__ >= 399000900)
201 	UIO_SETUP_SYSSPACE(uio);
202 #else
203 	uio->uio_segflg = UIO_SYSSPACE;
204 #endif
205 
206 	if (pad) {
207 		uio->uio_iovcnt++;
208 		uio->uio_iov[1].iov_base = pad_bytes;
209 		uio->uio_iov[1].iov_len = pad;
210 		uio->uio_resid += pad;
211 	}
212 
213 	if (conn->DataDigest) {
214 		i = uio->uio_iovcnt++;
215 		pdu->io_vec[i].iov_base = &pdu->data_digest;
216 		pdu->io_vec[i].iov_len = 4;
217 		uio->uio_resid += 4;
218 	}
219 #ifdef ISCSI_TEST_MODE
220 	/* save data pointer and size */
221 	pdu->save_uio.uio_iov = (struct iovec *) data;
222 	pdu->save_uio.uio_resid = len;
223 #endif
224 
225 	/* get the data */
226 	if (my_soo_read(conn, &pdu->uio, MSG_WAITALL) != 0) {
227 		return 1;
228 	}
229 	if (conn->DataDigest) {
230 		digest = gen_digest_2(data, len, pad_bytes, pad);
231 
232 		if (digest != pdu->data_digest) {
233 			DEBOUT(("Data Digest Error: comp = %08x, rx = %08x\n",
234 					digest, pdu->data_digest));
235 			switch (pdu->pdu.Opcode & OPCODE_MASK) {
236 			case TOP_SCSI_Response:
237 			case TOP_Text_Response:
238 				send_snack(pdu->connection, pdu, NULL, SNACK_STATUS_NAK);
239 				break;
240 
241 			case TOP_SCSI_Data_in:
242 				send_snack(pdu->connection, pdu, NULL, SNACK_DATA_NAK);
243 				break;
244 
245 			default:
246 				/* ignore all others */
247 				break;
248 			}
249 			return -1;
250 		}
251 	}
252 	return 0;
253 }
254 
255 
256 /*
257  * collect_text_data
258  *    Handle text continuation in login and text response PDUs
259  *
260  *    Parameter:
261  *          pdu      The received PDU
262  *          req_CCB  The CCB associated with the original request
263  *
264  *    Returns:    -1    if continue flag is set
265  *                0     if text is complete
266  *                +1    if an error occurred (out of resources)
267  */
268 STATIC int
269 collect_text_data(pdu_t *pdu, ccb_t *req_ccb)
270 {
271 
272 	if (req_ccb->text_data) {
273 		int nlen;
274 		uint8_t *newp;
275 
276 		nlen = req_ccb->text_len + pdu->temp_data_len;
277 		/* Note: allocate extra 2 bytes for text terminator */
278 		if ((newp = malloc(nlen + 2, M_TEMP, M_WAITOK)) == NULL) {
279 			req_ccb->status = ISCSI_STATUS_NO_RESOURCES;
280 			return 1;
281 		}
282 		memcpy(newp, req_ccb->text_data, req_ccb->text_len);
283 		memcpy(&newp[req_ccb->text_len], pdu->temp_data, pdu->temp_data_len);
284 
285 		free(req_ccb->text_data, M_TEMP);
286 		free(pdu->temp_data, M_TEMP);
287 
288 		req_ccb->text_data = NULL;
289 		pdu->temp_data = newp;
290 		pdu->temp_data_len = nlen;
291 	}
292 
293 	if (pdu->pdu.Flags & FLAG_CONTINUE) {
294 		req_ccb->text_data = pdu->temp_data;
295 		req_ccb->text_len = pdu->temp_data_len;
296 		pdu->temp_data = NULL;
297 
298 		acknowledge_text(req_ccb->connection, pdu, req_ccb);
299 		return -1;
300 	}
301 	return 0;
302 }
303 
304 
305 /*
306  * check_StatSN
307  *    Check received vs. expected StatSN
308  *
309  *    Parameter:
310  *          conn     The connection
311  *          nw_sn    The received StatSN in network byte order
312  *          ack      Acknowledge this SN if TRUE
313  */
314 
315 STATIC int
316 check_StatSN(connection_t *conn, uint32_t nw_sn, bool ack)
317 {
318 	int rc;
319 	uint32_t sn = ntohl(nw_sn);
320 
321 	rc = add_sernum(&conn->StatSN_buf, sn);
322 
323 	if (ack)
324 		ack_sernum(&conn->StatSN_buf, sn);
325 
326 	if (rc != 1) {
327 		if (!rc)
328 			return -1;
329 
330 		if (rc < 0) {
331 			DEBOUT(("Excessive outstanding Status PDUs, ExpSN %d, Recvd: %d\n",
332 					conn->StatSN_buf.ExpSN, sn));
333 			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
334 									RECOVER_CONNECTION);
335 			return rc;
336 		}
337 
338 		DEBOUT(("Missing Status PDUs: First %d, num: %d\n",
339 				conn->StatSN_buf.ExpSN, rc - 1));
340 		if (conn->state == ST_FULL_FEATURE &&
341 			conn->session->ErrorRecoveryLevel) {
342 			snack_missing(conn, NULL, SNACK_STATUS_NAK,
343 						  conn->StatSN_buf.ExpSN, rc - 1);
344 		} else {
345 			DEBOUT(("StatSN killing connection (State = %d, "
346 					"ErrorRecoveryLevel = %d)\n",
347 					conn->state, conn->session->ErrorRecoveryLevel));
348 			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
349 									RECOVER_CONNECTION);
350 			return -1;
351 		}
352 	}
353 	return 0;
354 }
355 
356 
357 /*
358  * check_CmdSN
359  *    Check received vs. expected CmdSN
360  *
361  *    Parameter:
362  *          conn     The connection
363  *          nw_sn    The received ExpCmdSN in network byte order
364  */
365 
366 STATIC void
367 check_CmdSN(connection_t *conn, uint32_t nw_sn)
368 {
369 	uint32_t sn = ntohl(nw_sn);
370 	ccb_t *ccb, *nxt;
371 
372 	for (ccb = TAILQ_FIRST(&conn->ccbs_waiting); ccb != NULL; ccb = nxt) {
373 		nxt = TAILQ_NEXT(ccb, chain);
374 		DEBC(conn, 10,
375 			("CheckCmdSN - CmdSN=%d, ExpCmdSn=%d, waiting=%p, flags=%x\n",
376 			ccb->CmdSN, sn, ccb->pdu_waiting, ccb->flags));
377 		if (ccb->pdu_waiting != NULL && ccb->CmdSN > sn &&
378 			!(ccb->flags & CCBF_GOT_RSP)) {
379 			DEBC(conn, 1, ("CheckCmdSN resending - CmdSN=%d, ExpCmdSn=%d\n",
380 						   ccb->CmdSN, sn));
381 
382 			ccb->total_tries++;
383 
384 			if (++ccb->num_timeouts > MAX_CCB_TIMEOUTS ||
385 				ccb->total_tries > MAX_CCB_TRIES) {
386 				handle_connection_error(conn, ISCSI_STATUS_TIMEOUT,
387 					(ccb->total_tries <= MAX_CCB_TRIES) ? RECOVER_CONNECTION
388 														: LOGOUT_CONNECTION);
389 				break;
390 			} else {
391 				resend_pdu(ccb);
392 			}
393 		}
394 	}
395 }
396 
397 
398 /*
399  * receive_login_pdu
400  *    Handle receipt of a login response PDU.
401  *
402  *    Parameter:
403  *          conn     The connection
404  *          pdu      The PDU
405  *          req_CCB  The CCB associated with the original request (if any)
406  */
407 
408 STATIC int
409 receive_login_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
410 {
411 	int rc;
412 
413 	DEBC(conn, 9, ("Received Login Response PDU, op=%x, flags=%x\n",
414 			pdu->pdu.Opcode, pdu->pdu.Flags));
415 
416 	if (req_ccb == NULL) {
417 		/* Duplicate?? */
418 		DEBOUT(("Received duplicate login response (no associated CCB)\n"));
419 		return -1;
420 	}
421 
422 	if (!conn->StatSN_buf.next_sn)
423 		conn->StatSN_buf.next_sn = conn->StatSN_buf.ExpSN =
424 			ntohl(pdu->pdu.p.login_rsp.StatSN) + 1;
425 	else if (check_StatSN(conn, pdu->pdu.p.login_rsp.StatSN, TRUE))
426 		return -1;
427 
428 	if (pdu->temp_data_len) {
429 		if ((rc = collect_text_data(pdu, req_ccb)) != 0) {
430 			return max(rc, 0);
431 		}
432 	}
433 
434 	if (pdu->pdu.p.login_rsp.StatusClass) {
435 		DEBC(conn, 1, ("Login problem - Class = %x, Detail = %x\n",
436 				pdu->pdu.p.login_rsp.StatusClass,
437 				pdu->pdu.p.login_rsp.StatusDetail));
438 
439 		req_ccb->status = ISCSI_STATUS_LOGIN_FAILED;
440 	} else {
441 		negotiate_login(conn, pdu, req_ccb);
442 		/* negotiate_login will decide whether login is complete or not */
443 		return 0;
444 	}
445 
446 	wake_ccb(req_ccb);
447 	return 0;
448 }
449 
450 
451 /*
452  * receive_text_response_pdu
453  *    Handle receipt of a text response PDU.
454  *
455  *    Parameter:
456  *          conn     The connection
457  *          pdu      The PDU
458  *          req_CCB  The CCB associated with the original request (if any)
459  */
460 
461 STATIC int
462 receive_text_response_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
463 {
464 	int rc;
465 
466 	DEBC(conn, 9, ("Received Text Response PDU, op=%x, flags=%x\n",
467 			pdu->pdu.Opcode, pdu->pdu.Flags));
468 
469 	if (check_StatSN(conn, pdu->pdu.p.text_rsp.StatSN, TRUE)) {
470 		return -1;
471 	}
472 	if (req_ccb == NULL) {
473 		DEBOUT(("Received unsolicited text response\n"));
474 		handle_connection_error(conn, ISCSI_STATUS_TARGET_ERROR,
475 							LOGOUT_CONNECTION);
476 		return -1;
477 	}
478 
479 	if (req_ccb->pdu_waiting != NULL) {
480 		SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
481 		req_ccb->num_timeouts = 0;
482 	}
483 
484 	if ((rc = collect_text_data(pdu, req_ccb)) != 0) {
485 		return max(0, rc);
486 	}
487 	negotiate_text(conn, pdu, req_ccb);
488 
489 	return 0;
490 }
491 
492 
493 /*
494  * receive_logout_pdu
495  *    Handle receipt of a logout response PDU.
496  *
497  *    Parameter:
498  *          conn     The connection
499  *          pdu      The PDU
500  *          req_CCB  The CCB associated with the original request (if any)
501  */
502 
503 STATIC int
504 receive_logout_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
505 {
506 	bool otherconn;
507 	uint8_t response;
508 
509 	otherconn = (req_ccb != NULL) ? (req_ccb->flags & CCBF_OTHERCONN) != 0 : 1;
510 	response = pdu->pdu.OpcodeSpecific [0];
511 	DEBC(conn, 1,
512 		("Received Logout PDU - CCB = %p, otherconn=%d, response=%d\n",
513 		req_ccb, otherconn, response));
514 
515 	if (req_ccb == NULL)
516 		return 0;
517 
518 	if (otherconn && check_StatSN(conn, pdu->pdu.p.logout_rsp.StatSN, TRUE))
519 		return -1;
520 
521 	switch (response) {
522 	case 0:
523 		req_ccb->status = ISCSI_STATUS_SUCCESS;
524 		break;
525 	case 1:
526 		req_ccb->status = ISCSI_STATUS_LOGOUT_CID_NOT_FOUND;
527 		break;
528 	case 2:
529 		req_ccb->status = ISCSI_STATUS_LOGOUT_RECOVERY_NS;
530 		break;
531 	default:
532 		req_ccb->status = ISCSI_STATUS_LOGOUT_ERROR;
533 		break;
534 	}
535 
536 	if (conn->session->ErrorRecoveryLevel >= 2 && response != 1) {
537 		connection_t *refconn = (otherconn) ? req_ccb->par : conn;
538 
539 		refconn->Time2Wait = ntohs(pdu->pdu.p.logout_rsp.Time2Wait);
540 		refconn->Time2Retain = ntohs(pdu->pdu.p.logout_rsp.Time2Retain);
541 	}
542 
543 	wake_ccb(req_ccb);
544 
545 	if (!otherconn && conn->state == ST_LOGOUT_SENT) {
546 		conn->terminating = ISCSI_STATUS_LOGOUT;
547 		conn->state = ST_SETTLING;
548 		conn->loggedout = (response) ? LOGOUT_FAILED : LOGOUT_SUCCESS;
549 
550 		callout_stop(&conn->timeout);
551 
552 #ifdef ISCSI_TEST_MODE
553 		test_remove_connection(conn);
554 #endif
555 		/* let send thread take over next step of cleanup */
556 		wakeup(&conn->pdus_to_send);
557 	}
558 
559 	return !otherconn;
560 }
561 
562 
563 /*
564  * receive_data_in_pdu
565  *    Handle receipt of a data in PDU.
566  *
567  *    Parameter:
568  *          conn     The connection
569  *          pdu      The PDU
570  *          req_CCB  The CCB associated with the original request (if any)
571  */
572 
573 STATIC int
574 receive_data_in_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
575 {
576 	uint32_t dsl, sn;
577 	bool done;
578 	int rc;
579 
580 	dsl = ntoh3(pdu->pdu.DataSegmentLength);
581 
582 	if (req_ccb == NULL || !req_ccb->data_in || !req_ccb->data_len) {
583 		DEBOUT(("Received Data In, but req_ccb not waiting for it, ignored\n"));
584 		return 0;
585 	}
586 	req_ccb->flags |= CCBF_GOT_RSP;
587 
588 	if (req_ccb->pdu_waiting != NULL) {
589 		SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
590 		req_ccb->num_timeouts = 0;
591 	}
592 
593 	sn = ntohl(pdu->pdu.p.data_in.DataSN);
594 
595 	if ((rc = add_sernum(&req_ccb->DataSN_buf, sn)) != 1) {
596 		if (!rc) {
597 			return -1;
598 		}
599 		if (rc < 0) {
600 			DEBOUT(("Excessive outstanding Data PDUs\n"));
601 			handle_connection_error(req_ccb->connection,
602 				ISCSI_STATUS_PDUS_LOST, LOGOUT_CONNECTION);
603 			return -1;
604 		}
605 		DEBOUT(("Missing Data PDUs: First %d, num: %d\n",
606 				req_ccb->DataSN_buf.ExpSN, rc - 1));
607 
608 		if (conn->state == ST_FULL_FEATURE &&
609 			conn->session->ErrorRecoveryLevel) {
610 			snack_missing(req_ccb->connection, req_ccb,
611 				SNACK_DATA_NAK, req_ccb->DataSN_buf.ExpSN,
612 				rc - 1);
613 		} else {
614 			DEBOUT(("Killing connection (State=%d, ErrorRecoveryLevel=%d)\n",
615 					conn->state, conn->session->ErrorRecoveryLevel));
616 			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
617 						LOGOUT_CONNECTION);
618 			return -1;
619 		}
620 	}
621 
622 	ack_sernum(&req_ccb->DataSN_buf, sn);
623 
624 	req_ccb->xfer_len += dsl;
625 
626 	if ((pdu->pdu.Flags & FLAG_ACK) && conn->session->ErrorRecoveryLevel)
627 		send_snack(conn, pdu, req_ccb, SNACK_DATA_ACK);
628 
629 	done = sn_empty(&req_ccb->DataSN_buf);
630 
631 	if (pdu->pdu.Flags & FLAG_STATUS) {
632 		DEBC(conn, 10, ("Rx Data In Complete, done = %d\n", done));
633 
634 		req_ccb->flags |= CCBF_COMPLETE;
635 		/* successful transfer, reset recover count */
636 		conn->recover = 0;
637 
638 		if (done) {
639 			wake_ccb(req_ccb);
640 		}
641 		if (check_StatSN(conn, pdu->pdu.p.data_in.StatSN, done)) {
642 			return -1;
643 		}
644 	} else if (done && (req_ccb->flags & CCBF_COMPLETE)) {
645 		wake_ccb(req_ccb);
646 	}
647 	/* else wait for command response */
648 
649 	return 0;
650 }
651 
652 
653 /*
654  * receive_r2t_pdu
655  *    Handle receipt of a R2T PDU.
656  *
657  *    Parameter:
658  *          conn     The connection
659  *          pdu      The PDU
660  *          req_CCB  The CCB associated with the original request (if any)
661  */
662 
663 STATIC int
664 receive_r2t_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
665 {
666 
667 	DEBC(conn, 10, ("Received R2T PDU - CCB = %p\n", req_ccb));
668 
669 	if (req_ccb != NULL) {
670 		if (req_ccb->pdu_waiting != NULL) {
671 			SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
672 			req_ccb->num_timeouts = 0;
673 		}
674 		send_data_out(conn, pdu, req_ccb, CCBDISP_NOWAIT, TRUE);
675 	}
676 
677 	return 0;
678 }
679 
680 
681 /*
682  * receive_command_response_pdu
683  *    Handle receipt of a command response PDU.
684  *
685  *    Parameter:
686  *          conn     The connection
687  *          pdu      The PDU
688  *          req_CCB  The CCB associated with the original request (if any)
689  */
690 
691 STATIC int
692 receive_command_response_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
693 {
694 	int len, rc;
695 	bool done;
696 
697 	/* Read any provided data */
698 	if (pdu->temp_data_len && req_ccb != NULL && req_ccb->sense_len_req) {
699 		len = min(req_ccb->sense_len_req,
700 				  ntohs(*((uint16_t *) pdu->temp_data)));
701 		memcpy(req_ccb->sense_ptr, ((uint16_t *) pdu->temp_data) + 1,
702 					len);
703 		req_ccb->sense_len_got = len;
704 	}
705 
706 	if (req_ccb == NULL) {
707 		/* Assume duplicate... */
708 		DEBOUT(("Possibly duplicate command response (no associated CCB)\n"));
709 		return -1;
710 	}
711 
712 	PERF_SNAP(req_ccb, PERF_PDURCVSTS);
713 
714 	if (req_ccb->pdu_waiting != NULL) {
715 		SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
716 		req_ccb->num_timeouts = 0;
717 	}
718 
719 	req_ccb->flags |= CCBF_COMPLETE;
720 	conn->recover = 0;	/* successful transfer, reset recover count */
721 
722 	if (pdu->pdu.OpcodeSpecific[0]) {	/* Response */
723 		req_ccb->status = ISCSI_STATUS_TARGET_FAILURE;
724 	} else {
725 		switch (pdu->pdu.OpcodeSpecific[1]) {	/* Status */
726 		case 0x00:
727 			/* success */
728 			break;
729 
730 		case 0x02:
731 			req_ccb->status = ISCSI_STATUS_CHECK_CONDITION;
732 			break;
733 
734 		case 0x08:
735 			req_ccb->status = ISCSI_STATUS_TARGET_BUSY;
736 			break;
737 
738 		default:
739 			req_ccb->status = ISCSI_STATUS_TARGET_ERROR;
740 			break;
741 		}
742 	}
743 
744 	if (pdu->pdu.Flags & (FLAG_OVERFLOW | FLAG_UNDERFLOW))
745 		req_ccb->residual = ntohl(pdu->pdu.p.response.ResidualCount);
746 
747 	done = req_ccb->status || sn_empty(&req_ccb->DataSN_buf);
748 
749 	DEBC(conn, 10, ("Rx Command Response rsp = %x, status = %x\n",
750 			pdu->pdu.OpcodeSpecific[0], pdu->pdu.OpcodeSpecific[1]));
751 
752 	rc = check_StatSN(conn, pdu->pdu.p.response.StatSN, done);
753 
754 	if (done)
755 		wake_ccb(req_ccb);
756 
757 	return rc;
758 }
759 
760 
761 /*
762  * receive_asynch_pdu
763  *    Handle receipt of an asynchronous message PDU.
764  *
765  *    Parameter:
766  *          conn     The connection
767  *          pdu      The PDU
768  */
769 
770 STATIC int
771 receive_asynch_pdu(connection_t *conn, pdu_t *pdu)
772 {
773 
774 	DEBOUT(("Received Asynch PDU, Event %d\n", pdu->pdu.p.asynch.AsyncEvent));
775 
776 	switch (pdu->pdu.p.asynch.AsyncEvent) {
777 	case 0:		   		/* SCSI Asynch event. Don't know what to do with it... */
778 		break;
779 
780 	case 1:		   		/* Target requests logout. */
781 		if (conn->session->active_connections > 1) {
782 			kill_connection(conn, ISCSI_STATUS_TARGET_LOGOUT,
783 						LOGOUT_CONNECTION, FALSE);
784 		} else {
785 			kill_session(conn->session, ISCSI_STATUS_TARGET_LOGOUT,
786 						 LOGOUT_SESSION, FALSE);
787 		}
788 		break;
789 
790 	case 2:				/* Target is dropping connection */
791 		conn = find_connection(conn->session,
792 					ntohs(pdu->pdu.p.asynch.Parameter1));
793 		if (conn != NULL) {
794 			conn->Time2Wait = ntohs(pdu->pdu.p.asynch.Parameter2);
795 			conn->Time2Retain = ntohs(pdu->pdu.p.asynch.Parameter3);
796 			kill_connection(conn, ISCSI_STATUS_TARGET_DROP,
797 					NO_LOGOUT, TRUE);
798 		}
799 		break;
800 
801 	case 3:				/* Target is dropping all connections of session */
802 		conn->session->DefaultTime2Wait = ntohs(pdu->pdu.p.asynch.Parameter2);
803 		conn->session->DefaultTime2Retain = ntohs(pdu->pdu.p.asynch.Parameter3);
804 		kill_session(conn->session, ISCSI_STATUS_TARGET_DROP, NO_LOGOUT, TRUE);
805 		break;
806 
807 	case 4:				/* Target requests parameter negotiation */
808 		start_text_negotiation(conn);
809 		break;
810 
811 	default:
812 		/* ignore */
813 		break;
814 	}
815 	return 0;
816 }
817 
818 
819 /*
820  * receive_reject_pdu
821  *    Handle receipt of a reject PDU.
822  *
823  *    Parameter:
824  *          conn     The connection
825  *          pdu      The PDU
826  */
827 
828 STATIC int
829 receive_reject_pdu(connection_t *conn, pdu_t *pdu)
830 {
831 	pdu_header_t *hpdu;
832 	ccb_t *req_ccb;
833 
834 	DEBOUT(("Received Reject PDU, reason = %x, data_len = %d\n",
835 			pdu->pdu.OpcodeSpecific[0], pdu->temp_data_len));
836 
837 	if (pdu->temp_data_len >= BHS_SIZE) {
838 		hpdu = (pdu_header_t *) pdu->temp_data;
839 		req_ccb = ccb_from_itt(conn, hpdu->InitiatorTaskTag);
840 
841 		DEBC(conn, 9, ("Reject PDU ITT (ccb)= %x (%p)\n",
842 				hpdu->InitiatorTaskTag, req_ccb));
843 		if (!req_ccb) {
844 			return 0;
845 		}
846 		switch (pdu->pdu.OpcodeSpecific[0]) {
847 		case REJECT_DIGEST_ERROR:
848 			/* don't retransmit data out */
849 			if ((hpdu->Opcode & OPCODE_MASK) == IOP_SCSI_Data_out)
850 				return 0;
851 			resend_pdu(req_ccb);
852 			return 0;
853 
854 		case REJECT_IMMED_COMMAND:
855 		case REJECT_LONG_OPERATION:
856 			resend_pdu(req_ccb);
857 			return 0;
858 
859 		case REJECT_SNACK:
860 		case REJECT_PROTOCOL_ERROR:
861 			req_ccb->status = ISCSI_STATUS_PROTOCOL_ERROR;
862 			break;
863 
864 		case REJECT_CMD_NOT_SUPPORTED:
865 			req_ccb->status = ISCSI_STATUS_CMD_NOT_SUPPORTED;
866 			break;
867 
868 		case REJECT_INVALID_PDU_FIELD:
869 			req_ccb->status = ISCSI_STATUS_PDU_ERROR;
870 			break;
871 
872 		default:
873 			req_ccb->status = ISCSI_STATUS_GENERAL_ERROR;
874 			break;
875 		}
876 
877 		wake_ccb(req_ccb);
878 		handle_connection_error(conn, ISCSI_STATUS_PROTOCOL_ERROR,
879 							LOGOUT_CONNECTION);
880 	}
881 	return 0;
882 }
883 
884 
885 /*
886  * receive_task_management_pdu
887  *    Handle receipt of a task management PDU.
888  *
889  *    Parameter:
890  *          conn     The connection
891  *          pdu      The PDU
892  *          req_CCB  The CCB associated with the original request (if any)
893  */
894 
895 STATIC int
896 receive_task_management_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
897 {
898 
899 	DEBC(conn, 2, ("Received Task Management PDU, response %d, req_ccb %p\n",
900 			pdu->pdu.OpcodeSpecific[0], req_ccb));
901 
902 	if (req_ccb != NULL) {
903 		switch (pdu->pdu.OpcodeSpecific[0]) {	/* Response */
904 		case 0:
905 			req_ccb->status = ISCSI_STATUS_SUCCESS;
906 			break;
907 		case 1:
908 			req_ccb->status = ISCSI_STATUS_TASK_NOT_FOUND;
909 			break;
910 		case 2:
911 			req_ccb->status = ISCSI_STATUS_LUN_NOT_FOUND;
912 			break;
913 		case 3:
914 			req_ccb->status = ISCSI_STATUS_TASK_ALLEGIANT;
915 			break;
916 		case 4:
917 			req_ccb->status = ISCSI_STATUS_CANT_REASSIGN;
918 			break;
919 		case 5:
920 			req_ccb->status = ISCSI_STATUS_FUNCTION_UNSUPPORTED;
921 			break;
922 		case 6:
923 			req_ccb->status = ISCSI_STATUS_FUNCTION_NOT_AUTHORIZED;
924 			break;
925 		case 255:
926 			req_ccb->status = ISCSI_STATUS_FUNCTION_REJECTED;
927 			break;
928 		default:
929 			req_ccb->status = ISCSI_STATUS_UNKNOWN_REASON;
930 			break;
931 		}
932 		wake_ccb(req_ccb);
933 	}
934 
935 	check_StatSN(conn, pdu->pdu.p.task_rsp.StatSN, TRUE);
936 
937 	return 0;
938 }
939 
940 
941 /*
942  * receive_nop_in_pdu
943  *    Handle receipt of a Nop-In PDU.
944  *
945  *    Parameter:
946  *          conn     The connection
947  *          pdu      The PDU
948  *          req_CCB  The CCB associated with the original request (if any)
949  */
950 
951 STATIC int
952 receive_nop_in_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
953 {
954 	DEBC(conn, 10,
955 		("Received NOP-In PDU, req_ccb=%p, ITT=%x, TTT=%x, StatSN=%x\n",
956 		req_ccb, pdu->pdu.InitiatorTaskTag,
957 		pdu->pdu.p.nop_in.TargetTransferTag,
958 		ntohl(pdu->pdu.p.nop_in.StatSN)));
959 
960 	if (pdu->pdu.InitiatorTaskTag == 0xffffffff) {
961 		/* this is a target ping - respond with a pong */
962 		if (pdu->pdu.p.nop_in.TargetTransferTag != 0xffffffff)
963 			send_nop_out(conn, pdu);
964 
965 		/*
966 		   Any receive resets the connection timeout, but we got a ping, which
967 		   means that it's likely the other side was waiting for something to
968 		   happen on the connection. If we aren't idle, send a ping right
969 		   away to synch counters (don't synch on this ping because other
970 		   PDUs may be on the way).
971 		 */
972 		if (TAILQ_FIRST(&conn->ccbs_waiting) != NULL)
973 			send_nop_out(conn, NULL);
974 	} else if (req_ccb != NULL) {
975 		/* this is a solicited ping, check CmdSN for lost commands */
976 		/* and advance StatSN */
977 		check_CmdSN(conn, pdu->pdu.p.nop_in.ExpCmdSN);
978 
979 		wake_ccb(req_ccb);
980 
981 		check_StatSN(conn, pdu->pdu.p.nop_in.StatSN, TRUE);
982 	}
983 
984 	return 0;
985 }
986 
987 
988 /*
989  * receive_pdu
990  *    Get parameters, call the appropriate handler for a received PDU.
991  *
992  *    Parameter:
993  *          conn     The connection
994  *          pdu      The PDU
995  *
996  *    Returns:    0 on success, nonzero if the connection is broken.
997  */
998 
999 STATIC int
1000 receive_pdu(connection_t *conn, pdu_t *pdu)
1001 {
1002 	ccb_t *req_ccb;
1003 	ccb_list_t waiting;
1004 	int rc;
1005 	uint32_t MaxCmdSN, digest;
1006 	session_t *sess = conn->session;
1007 
1008 	if (conn->HeaderDigest) {
1009 		digest = gen_digest(&pdu->pdu, BHS_SIZE);
1010 		if (digest != pdu->pdu.HeaderDigest) {
1011 			DEBOUT(("Header Digest Error: comp = %08x, rx = %08x\n",
1012 					digest, pdu->pdu.HeaderDigest));
1013 #ifdef ISCSI_TEST_MODE
1014 			test_mode_rx(conn, pdu, TEST_INVALID_HEADER_CRC);
1015 #endif
1016 			/* try to skip to next PDU */
1017 			try_resynch_receive(conn);
1018 			free_pdu(pdu);
1019 			return 0;
1020 		}
1021 	}
1022 
1023 	req_ccb = ccb_from_itt(conn, pdu->pdu.InitiatorTaskTag);
1024 
1025 	if (req_ccb != NULL && req_ccb->data_in && req_ccb->data_len &&
1026 		(pdu->pdu.Opcode & OPCODE_MASK) == TOP_SCSI_Data_in) {
1027 		uint32_t dsl, offset;
1028 
1029 		dsl = ntoh3(pdu->pdu.DataSegmentLength);
1030 		offset = ntohl(pdu->pdu.p.data_in.BufferOffset);
1031 
1032 		if ((offset + dsl) > req_ccb->data_len) {
1033 			DEBOUT(("Received more data than requested (len %d, offset %d)\n",
1034 					dsl, offset));
1035 			handle_connection_error(conn, ISCSI_STATUS_TARGET_ERROR, NO_LOGOUT);
1036 			return 1;
1037 		}
1038 		DEBC(conn, 10,
1039 			("Received Data in PDU - CCB = %p, Datalen = %d, Offset = %d\n",
1040 			req_ccb, dsl, offset));
1041 
1042 		PERF_SNAPC(req_ccb, PERF_BEGIN_PDURCVDATA);
1043 		rc = read_pdu_data(pdu, req_ccb->data_ptr, offset);
1044 		PERF_SNAP(req_ccb, PERF_END_PDURCVDATA);
1045 	} else {
1046 		rc = read_pdu_data(pdu, NULL, 0);
1047 	}
1048 #ifdef ISCSI_TEST_MODE
1049 	if (test_mode_rx(conn, pdu, rc)) {
1050 		free_pdu(pdu);
1051 		return rc;
1052 	}
1053 #endif
1054 	if (!rc && (conn->state <= ST_WINDING_DOWN ||
1055 		(pdu->pdu.Opcode & OPCODE_MASK) == TOP_Logout_Response)) {
1056 
1057 		switch (pdu->pdu.Opcode & OPCODE_MASK) {
1058 		case TOP_NOP_In:
1059 			rc = receive_nop_in_pdu(conn, pdu, req_ccb);
1060 			break;
1061 
1062 		case TOP_SCSI_Response:
1063 			rc = receive_command_response_pdu(conn, pdu, req_ccb);
1064 			break;
1065 
1066 		case TOP_SCSI_Task_Management:
1067 			rc = receive_task_management_pdu(conn, pdu, req_ccb);
1068 			break;
1069 
1070 		case TOP_Login_Response:
1071 			rc = receive_login_pdu(conn, pdu, req_ccb);
1072 			break;
1073 
1074 		case TOP_Text_Response:
1075 			rc = receive_text_response_pdu(conn, pdu, req_ccb);
1076 			break;
1077 
1078 		case TOP_SCSI_Data_in:
1079 			rc = receive_data_in_pdu(conn, pdu, req_ccb);
1080 			break;
1081 
1082 		case TOP_Logout_Response:
1083 			rc = receive_logout_pdu(conn, pdu, req_ccb);
1084 			break;
1085 
1086 		case TOP_R2T:
1087 			rc = receive_r2t_pdu(conn, pdu, req_ccb);
1088 			break;
1089 
1090 		case TOP_Asynchronous_Message:
1091 			rc = receive_asynch_pdu(conn, pdu);
1092 			break;
1093 
1094 		case TOP_Reject:
1095 			rc = receive_reject_pdu(conn, pdu);
1096 			break;
1097 
1098 		default:
1099 			DEBOUT(("Received Invalid Opcode %x\n", pdu->pdu.Opcode));
1100 			try_resynch_receive(conn);
1101 			rc = -1;
1102 			break;
1103 		}
1104 	}
1105 
1106 	free_pdu(pdu);
1107 	if (rc)
1108 		return rc;
1109 
1110 	/* MaxCmdSN and ExpCmdSN are in the same place in all received PDUs */
1111 	sess->ExpCmdSN = max(sess->ExpCmdSN, ntohl(pdu->pdu.p.nop_in.ExpCmdSN));
1112 	MaxCmdSN = ntohl(pdu->pdu.p.nop_in.MaxCmdSN);
1113 
1114 	/* received a valid frame, reset timeout */
1115 
1116 	SET_CONN_TIMEOUT(conn,
1117 			(((pdu->pdu.Opcode & OPCODE_MASK) == TOP_NOP_In) &&
1118 			(TAILQ_FIRST(&conn->ccbs_waiting) == NULL)) ?
1119 			conn->idle_timeout_val : CONNECTION_TIMEOUT);
1120 	conn->num_timeouts = 0;
1121 
1122 	/*
1123 	 * Un-throttle - wakeup all CCBs waiting for MaxCmdSN to increase.
1124 	 * We have to handle wait/nowait CCBs a bit differently.
1125 	 */
1126 	if (MaxCmdSN != sess->MaxCmdSN) {
1127 		sess->MaxCmdSN = MaxCmdSN;
1128 #if 0
1129 /* XXX - agc */
1130 		if (TAILQ_FIRST(&sess->ccbs_throttled) == NULL ||
1131 			!sn_a_lt_b(sess->CmdSN, MaxCmdSN))
1132 			return 0;
1133 #else
1134 		if (TAILQ_FIRST(&sess->ccbs_throttled) == NULL)
1135 			return 0;
1136 #endif
1137 
1138 		DEBC(conn, 1, ("Unthrottling - MaxCmdSN = %d\n", MaxCmdSN));
1139 
1140 		CS_BEGIN;
1141 		waiting = sess->ccbs_throttled;
1142 		TAILQ_INIT(&sess->ccbs_throttled);
1143 		CS_END;
1144 		while ((req_ccb = TAILQ_FIRST(&waiting)) != NULL) {
1145 			TAILQ_REMOVE(&waiting, req_ccb, chain);
1146 			DEBC(conn, 1, ("Unthrottling - ccb = %p, disp = %d\n",
1147 					req_ccb, req_ccb->disp));
1148 
1149 			if (req_ccb->flags & CCBF_WAITING)
1150 				wakeup(req_ccb);
1151 			else
1152 				send_command(req_ccb, req_ccb->disp, FALSE, FALSE);
1153 		}
1154 	}
1155 
1156 	return 0;
1157 }
1158 
1159 /*****************************************************************************/
1160 
1161 /*
1162  * iscsi_receive_thread
1163  *    Per connection thread handling receive data.
1164  *
1165  *    Parameter:
1166  *          conn     The connection
1167  */
1168 
1169 void
1170 iscsi_rcv_thread(void *par)
1171 {
1172 	connection_t *conn = (connection_t *) par;
1173 	pdu_t *pdu;
1174 	size_t hlen;
1175 
1176 	do {
1177 		while (!conn->terminating) {
1178 			pdu = get_pdu(conn);
1179 			pdu->uio.uio_iov = pdu->io_vec;
1180 			UIO_SETUP_SYSSPACE(&pdu->uio);
1181 			pdu->uio.uio_iovcnt = 1;
1182 			pdu->uio.uio_rw = UIO_READ;
1183 
1184 			pdu->io_vec[0].iov_base = &pdu->pdu;
1185 			hlen = (conn->HeaderDigest) ? BHS_SIZE + 4 : BHS_SIZE;
1186 			pdu->io_vec[0].iov_len = hlen;
1187 			pdu->uio.uio_resid = hlen;
1188 
1189 			DEBC(conn, 99, ("Receive thread waiting for data\n"));
1190 			if (my_soo_read(conn, &pdu->uio, MSG_WAITALL)) {
1191 				free_pdu(pdu);
1192 				break;
1193 			}
1194 			/* Check again for header digest */
1195 			/* (it may have changed during the wait) */
1196 			if (hlen == BHS_SIZE && conn->HeaderDigest) {
1197 				pdu->uio.uio_iov = pdu->io_vec;
1198 				pdu->uio.uio_iovcnt = 1;
1199 				pdu->io_vec[0].iov_base = &pdu->pdu.HeaderDigest;
1200 				pdu->io_vec[0].iov_len = 4;
1201 				pdu->uio.uio_resid = 4;
1202 				if (my_soo_read(conn, &pdu->uio, MSG_WAITALL)) {
1203 					free_pdu(pdu);
1204 					break;
1205 				}
1206 			}
1207 
1208 			if (receive_pdu(conn, pdu) > 0) {
1209 				break;
1210 			}
1211 		}
1212 		if (!conn->destroy) {
1213 			tsleep(conn, PRIBIO, "conn_idle", 0);
1214 		}
1215 	} while (!conn->destroy);
1216 
1217 	conn->rcvproc = NULL;
1218 	DEBC(conn, 5, ("Receive thread exits\n"));
1219 	kthread_exit(0);
1220 }
1221