1/*	$NetBSD: iscsi_rcv.c,v 1.1.8.1 2012/06/12 19:41:25 riz 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
51STATIC int
52my_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
84STATIC void
85try_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
124STATIC ccb_t *
125ccb_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
157STATIC int
158read_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	DEBOUT(("read_pdu_data: data segment length = %d\n",
167		ntoh3(pdu->pdu.DataSegmentLength)));
168	if (!(len = ntoh3(pdu->pdu.DataSegmentLength))) {
169		return 0;
170	}
171	pad = len & 0x03;
172	if (pad) {
173		pad = 4 - pad;
174	}
175	assert((data != NULL) || (offset == 0));
176
177	if (data == NULL) {
178		/*
179		 * NOTE: Always allocate 2 extra bytes when reading temp data,
180		 * since temp data is mostly used for received text, and we can
181		 * make sure there's a double zero at the end of the data to mark EOF.
182		 */
183		if ((data = (uint8_t *) malloc(len + 2, M_TEMP, M_WAITOK)) == NULL) {
184			DEBOUT(("ran out of mem on receive\n"));
185			handle_connection_error(pdu->connection,
186				ISCSI_STATUS_NO_RESOURCES, LOGOUT_SESSION);
187			return 1;
188		}
189		pdu->temp_data = data;
190		pdu->temp_data_len = len;
191	}
192
193	pdu->io_vec[0].iov_base = data + offset;
194	pdu->io_vec[0].iov_len = len;
195
196	uio = &pdu->uio;
197
198	uio->uio_iov = pdu->io_vec;
199	uio->uio_iovcnt = 1;
200	uio->uio_rw = UIO_READ;
201	uio->uio_resid = len;
202#if (__NetBSD_Version__ >= 399000900)
203	UIO_SETUP_SYSSPACE(uio);
204#else
205	uio->uio_segflg = UIO_SYSSPACE;
206#endif
207
208	if (pad) {
209		uio->uio_iovcnt++;
210		uio->uio_iov[1].iov_base = pad_bytes;
211		uio->uio_iov[1].iov_len = pad;
212		uio->uio_resid += pad;
213	}
214
215	if (conn->DataDigest) {
216		i = uio->uio_iovcnt++;
217		pdu->io_vec[i].iov_base = &pdu->data_digest;
218		pdu->io_vec[i].iov_len = 4;
219		uio->uio_resid += 4;
220	}
221#ifdef ISCSI_TEST_MODE
222	/* save data pointer and size */
223	pdu->save_uio.uio_iov = (struct iovec *) data;
224	pdu->save_uio.uio_resid = len;
225#endif
226
227	/* get the data */
228	if (my_soo_read(conn, &pdu->uio, MSG_WAITALL) != 0) {
229		return 1;
230	}
231	if (conn->DataDigest) {
232		digest = gen_digest_2(data, len, pad_bytes, pad);
233
234		if (digest != pdu->data_digest) {
235			DEBOUT(("Data Digest Error: comp = %08x, rx = %08x\n",
236					digest, pdu->data_digest));
237			switch (pdu->pdu.Opcode & OPCODE_MASK) {
238			case TOP_SCSI_Response:
239			case TOP_Text_Response:
240				send_snack(pdu->connection, pdu, NULL, SNACK_STATUS_NAK);
241				break;
242
243			case TOP_SCSI_Data_in:
244				send_snack(pdu->connection, pdu, NULL, SNACK_DATA_NAK);
245				break;
246
247			default:
248				/* ignore all others */
249				break;
250			}
251			return -1;
252		}
253	}
254	return 0;
255}
256
257
258/*
259 * collect_text_data
260 *    Handle text continuation in login and text response PDUs
261 *
262 *    Parameter:
263 *          pdu      The received PDU
264 *          req_CCB  The CCB associated with the original request
265 *
266 *    Returns:    -1    if continue flag is set
267 *                0     if text is complete
268 *                +1    if an error occurred (out of resources)
269 */
270STATIC int
271collect_text_data(pdu_t *pdu, ccb_t *req_ccb)
272{
273
274	if (req_ccb->text_data) {
275		int nlen;
276		uint8_t *newp;
277
278		nlen = req_ccb->text_len + pdu->temp_data_len;
279		/* Note: allocate extra 2 bytes for text terminator */
280		if ((newp = malloc(nlen + 2, M_TEMP, M_WAITOK)) == NULL) {
281			req_ccb->status = ISCSI_STATUS_NO_RESOURCES;
282			return 1;
283		}
284		memcpy(newp, req_ccb->text_data, req_ccb->text_len);
285		memcpy(&newp[req_ccb->text_len], pdu->temp_data, pdu->temp_data_len);
286
287		free(req_ccb->text_data, M_TEMP);
288		free(pdu->temp_data, M_TEMP);
289
290		req_ccb->text_data = NULL;
291		pdu->temp_data = newp;
292		pdu->temp_data_len = nlen;
293	}
294
295	if (pdu->pdu.Flags & FLAG_CONTINUE) {
296		req_ccb->text_data = pdu->temp_data;
297		req_ccb->text_len = pdu->temp_data_len;
298		pdu->temp_data = NULL;
299
300		acknowledge_text(req_ccb->connection, pdu, req_ccb);
301		return -1;
302	}
303	return 0;
304}
305
306
307/*
308 * check_StatSN
309 *    Check received vs. expected StatSN
310 *
311 *    Parameter:
312 *          conn     The connection
313 *          nw_sn    The received StatSN in network byte order
314 *          ack      Acknowledge this SN if TRUE
315 */
316
317STATIC int
318check_StatSN(connection_t *conn, uint32_t nw_sn, bool ack)
319{
320	int rc;
321	uint32_t sn = ntohl(nw_sn);
322
323	rc = add_sernum(&conn->StatSN_buf, sn);
324
325	if (ack)
326		ack_sernum(&conn->StatSN_buf, sn);
327
328	if (rc != 1) {
329		if (rc == 0) {
330			DEBOUT(("Duplicate PDU, ExpSN %d, Recvd: %d\n",
331				conn->StatSN_buf.ExpSN, sn));
332			return -1;
333		}
334
335		if (rc < 0) {
336			DEBOUT(("Excessive outstanding Status PDUs, ExpSN %d, Recvd: %d\n",
337					conn->StatSN_buf.ExpSN, sn));
338			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
339									RECOVER_CONNECTION);
340			return rc;
341		}
342
343		DEBOUT(("Missing Status PDUs: First %d, num: %d\n",
344				conn->StatSN_buf.ExpSN, rc - 1));
345		if (conn->state == ST_FULL_FEATURE &&
346			conn->session->ErrorRecoveryLevel) {
347			snack_missing(conn, NULL, SNACK_STATUS_NAK,
348						  conn->StatSN_buf.ExpSN, rc - 1);
349		} else {
350			DEBOUT(("StatSN killing connection (State = %d, "
351					"ErrorRecoveryLevel = %d)\n",
352					conn->state, conn->session->ErrorRecoveryLevel));
353			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
354									RECOVER_CONNECTION);
355			return -1;
356		}
357	}
358	return 0;
359}
360
361
362/*
363 * check_CmdSN
364 *    Check received vs. expected CmdSN
365 *
366 *    Parameter:
367 *          conn     The connection
368 *          nw_sn    The received ExpCmdSN in network byte order
369 */
370
371STATIC void
372check_CmdSN(connection_t *conn, uint32_t nw_sn)
373{
374	uint32_t sn = ntohl(nw_sn);
375	ccb_t *ccb, *nxt;
376
377	for (ccb = TAILQ_FIRST(&conn->ccbs_waiting); ccb != NULL; ccb = nxt) {
378		nxt = TAILQ_NEXT(ccb, chain);
379		DEBC(conn, 10,
380			("CheckCmdSN - CmdSN=%d, ExpCmdSn=%d, waiting=%p, flags=%x\n",
381			ccb->CmdSN, sn, ccb->pdu_waiting, ccb->flags));
382		if (ccb->pdu_waiting != NULL && ccb->CmdSN > sn &&
383			!(ccb->flags & CCBF_GOT_RSP)) {
384			DEBC(conn, 1, ("CheckCmdSN resending - CmdSN=%d, ExpCmdSn=%d\n",
385						   ccb->CmdSN, sn));
386
387			ccb->total_tries++;
388
389			if (++ccb->num_timeouts > MAX_CCB_TIMEOUTS ||
390				ccb->total_tries > MAX_CCB_TRIES) {
391				handle_connection_error(conn, ISCSI_STATUS_TIMEOUT,
392					(ccb->total_tries <= MAX_CCB_TRIES) ? RECOVER_CONNECTION
393														: LOGOUT_CONNECTION);
394				break;
395			} else {
396				resend_pdu(ccb);
397			}
398		}
399	}
400}
401
402
403/*
404 * receive_login_pdu
405 *    Handle receipt of a login response PDU.
406 *
407 *    Parameter:
408 *          conn     The connection
409 *          pdu      The PDU
410 *          req_CCB  The CCB associated with the original request (if any)
411 */
412
413STATIC int
414receive_login_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
415{
416	int rc;
417
418	DEBC(conn, 9, ("Received Login Response PDU, op=%x, flags=%x, sn=%u\n",
419			pdu->pdu.Opcode, pdu->pdu.Flags,
420			ntohl(pdu->pdu.p.login_rsp.StatSN)));
421
422	if (req_ccb == NULL) {
423		/* Duplicate?? */
424		DEBOUT(("Received duplicate login response (no associated CCB)\n"));
425		return -1;
426	}
427
428	if (pdu->pdu.p.login_rsp.StatusClass) {
429		DEBC(conn, 1, ("Login problem - Class = %x, Detail = %x\n",
430				pdu->pdu.p.login_rsp.StatusClass,
431				pdu->pdu.p.login_rsp.StatusDetail));
432
433		req_ccb->status = ISCSI_STATUS_LOGIN_FAILED;
434		/* XXX */
435		wake_ccb(req_ccb);
436		return 0;
437	}
438
439	if (!conn->StatSN_buf.next_sn) {
440		conn->StatSN_buf.next_sn = conn->StatSN_buf.ExpSN =
441			ntohl(pdu->pdu.p.login_rsp.StatSN) + 1;
442	} else if (check_StatSN(conn, pdu->pdu.p.login_rsp.StatSN, TRUE))
443		return -1;
444
445	if (pdu->temp_data_len) {
446		if ((rc = collect_text_data(pdu, req_ccb)) != 0)
447			return max(rc, 0);
448	}
449
450	negotiate_login(conn, pdu, req_ccb);
451
452	/* negotiate_login will decide whether login is complete or not */
453	return 0;
454}
455
456
457/*
458 * receive_text_response_pdu
459 *    Handle receipt of a text response PDU.
460 *
461 *    Parameter:
462 *          conn     The connection
463 *          pdu      The PDU
464 *          req_CCB  The CCB associated with the original request (if any)
465 */
466
467STATIC int
468receive_text_response_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
469{
470	int rc;
471
472	DEBC(conn, 9, ("Received Text Response PDU, op=%x, flags=%x\n",
473			pdu->pdu.Opcode, pdu->pdu.Flags));
474
475	if (check_StatSN(conn, pdu->pdu.p.text_rsp.StatSN, TRUE)) {
476		return -1;
477	}
478	if (req_ccb == NULL) {
479		DEBOUT(("Received unsolicited text response\n"));
480		handle_connection_error(conn, ISCSI_STATUS_TARGET_ERROR,
481							LOGOUT_CONNECTION);
482		return -1;
483	}
484
485	if (req_ccb->pdu_waiting != NULL) {
486		SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
487		req_ccb->num_timeouts = 0;
488	}
489
490	if ((rc = collect_text_data(pdu, req_ccb)) != 0) {
491		return max(0, rc);
492	}
493	negotiate_text(conn, pdu, req_ccb);
494
495	return 0;
496}
497
498
499/*
500 * receive_logout_pdu
501 *    Handle receipt of a logout response PDU.
502 *
503 *    Parameter:
504 *          conn     The connection
505 *          pdu      The PDU
506 *          req_CCB  The CCB associated with the original request (if any)
507 */
508
509STATIC int
510receive_logout_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
511{
512	bool otherconn;
513	uint8_t response;
514
515	otherconn = (req_ccb != NULL) ? (req_ccb->flags & CCBF_OTHERCONN) != 0 : 1;
516	response = pdu->pdu.OpcodeSpecific [0];
517	DEBC(conn, 1,
518		("Received Logout PDU - CCB = %p, otherconn=%d, response=%d\n",
519		req_ccb, otherconn, response));
520
521	if (req_ccb == NULL)
522		return 0;
523
524	if (otherconn && check_StatSN(conn, pdu->pdu.p.logout_rsp.StatSN, TRUE))
525		return -1;
526
527	switch (response) {
528	case 0:
529		req_ccb->status = ISCSI_STATUS_SUCCESS;
530		break;
531	case 1:
532		req_ccb->status = ISCSI_STATUS_LOGOUT_CID_NOT_FOUND;
533		break;
534	case 2:
535		req_ccb->status = ISCSI_STATUS_LOGOUT_RECOVERY_NS;
536		break;
537	default:
538		req_ccb->status = ISCSI_STATUS_LOGOUT_ERROR;
539		break;
540	}
541
542	if (conn->session->ErrorRecoveryLevel >= 2 && response != 1) {
543		connection_t *refconn = (otherconn) ? req_ccb->par : conn;
544
545		refconn->Time2Wait = ntohs(pdu->pdu.p.logout_rsp.Time2Wait);
546		refconn->Time2Retain = ntohs(pdu->pdu.p.logout_rsp.Time2Retain);
547	}
548
549	wake_ccb(req_ccb);
550
551	if (!otherconn && conn->state == ST_LOGOUT_SENT) {
552		conn->terminating = ISCSI_STATUS_LOGOUT;
553		conn->state = ST_SETTLING;
554		conn->loggedout = (response) ? LOGOUT_FAILED : LOGOUT_SUCCESS;
555
556		callout_stop(&conn->timeout);
557
558#ifdef ISCSI_TEST_MODE
559		test_remove_connection(conn);
560#endif
561		/* let send thread take over next step of cleanup */
562		wakeup(&conn->pdus_to_send);
563	}
564
565	return !otherconn;
566}
567
568
569/*
570 * receive_data_in_pdu
571 *    Handle receipt of a data in PDU.
572 *
573 *    Parameter:
574 *          conn     The connection
575 *          pdu      The PDU
576 *          req_CCB  The CCB associated with the original request (if any)
577 */
578
579STATIC int
580receive_data_in_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
581{
582	uint32_t dsl, sn;
583	bool done;
584	int rc;
585
586	dsl = ntoh3(pdu->pdu.DataSegmentLength);
587
588	if (req_ccb == NULL || !req_ccb->data_in || !req_ccb->data_len) {
589		DEBOUT(("Received Data In, but req_ccb not waiting for it, ignored\n"));
590		return 0;
591	}
592	req_ccb->flags |= CCBF_GOT_RSP;
593
594	if (req_ccb->pdu_waiting != NULL) {
595		SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
596		req_ccb->num_timeouts = 0;
597	}
598
599	sn = ntohl(pdu->pdu.p.data_in.DataSN);
600
601	if ((rc = add_sernum(&req_ccb->DataSN_buf, sn)) != 1) {
602		if (!rc) {
603			return -1;
604		}
605		if (rc < 0) {
606			DEBOUT(("Excessive outstanding Data PDUs\n"));
607			handle_connection_error(req_ccb->connection,
608				ISCSI_STATUS_PDUS_LOST, LOGOUT_CONNECTION);
609			return -1;
610		}
611		DEBOUT(("Missing Data PDUs: First %d, num: %d\n",
612				req_ccb->DataSN_buf.ExpSN, rc - 1));
613
614		if (conn->state == ST_FULL_FEATURE &&
615			conn->session->ErrorRecoveryLevel) {
616			snack_missing(req_ccb->connection, req_ccb,
617				SNACK_DATA_NAK, req_ccb->DataSN_buf.ExpSN,
618				rc - 1);
619		} else {
620			DEBOUT(("Killing connection (State=%d, ErrorRecoveryLevel=%d)\n",
621					conn->state, conn->session->ErrorRecoveryLevel));
622			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
623						LOGOUT_CONNECTION);
624			return -1;
625		}
626	}
627
628	ack_sernum(&req_ccb->DataSN_buf, sn);
629
630	req_ccb->xfer_len += dsl;
631
632	if ((pdu->pdu.Flags & FLAG_ACK) && conn->session->ErrorRecoveryLevel)
633		send_snack(conn, pdu, req_ccb, SNACK_DATA_ACK);
634
635	done = sn_empty(&req_ccb->DataSN_buf);
636
637	if (pdu->pdu.Flags & FLAG_STATUS) {
638		DEBC(conn, 10, ("Rx Data In Complete, done = %d\n", done));
639
640		req_ccb->flags |= CCBF_COMPLETE;
641		/* successful transfer, reset recover count */
642		conn->recover = 0;
643
644		if (done) {
645			wake_ccb(req_ccb);
646		}
647		if (check_StatSN(conn, pdu->pdu.p.data_in.StatSN, done)) {
648			return -1;
649		}
650	} else if (done && (req_ccb->flags & CCBF_COMPLETE)) {
651		wake_ccb(req_ccb);
652	}
653	/* else wait for command response */
654
655	return 0;
656}
657
658
659/*
660 * receive_r2t_pdu
661 *    Handle receipt of a R2T PDU.
662 *
663 *    Parameter:
664 *          conn     The connection
665 *          pdu      The PDU
666 *          req_CCB  The CCB associated with the original request (if any)
667 */
668
669STATIC int
670receive_r2t_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
671{
672
673	DEBC(conn, 10, ("Received R2T PDU - CCB = %p\n", req_ccb));
674
675	if (req_ccb != NULL) {
676		if (req_ccb->pdu_waiting != NULL) {
677			SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
678			req_ccb->num_timeouts = 0;
679		}
680		send_data_out(conn, pdu, req_ccb, CCBDISP_NOWAIT, TRUE);
681	}
682
683	return 0;
684}
685
686
687/*
688 * receive_command_response_pdu
689 *    Handle receipt of a command response PDU.
690 *
691 *    Parameter:
692 *          conn     The connection
693 *          pdu      The PDU
694 *          req_CCB  The CCB associated with the original request (if any)
695 */
696
697STATIC int
698receive_command_response_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
699{
700	int len, rc;
701	bool done;
702
703	/* Read any provided data */
704	if (pdu->temp_data_len && req_ccb != NULL && req_ccb->sense_len_req) {
705		len = min(req_ccb->sense_len_req,
706				  ntohs(*((uint16_t *) pdu->temp_data)));
707		memcpy(req_ccb->sense_ptr, ((uint16_t *) pdu->temp_data) + 1,
708					len);
709		req_ccb->sense_len_got = len;
710	}
711
712	if (req_ccb == NULL) {
713		/* Assume duplicate... */
714		DEBOUT(("Possibly duplicate command response (no associated CCB)\n"));
715		return -1;
716	}
717
718	PERF_SNAP(req_ccb, PERF_PDURCVSTS);
719
720	if (req_ccb->pdu_waiting != NULL) {
721		SET_CCB_TIMEOUT(conn, req_ccb, COMMAND_TIMEOUT);
722		req_ccb->num_timeouts = 0;
723	}
724
725	req_ccb->flags |= CCBF_COMPLETE;
726	conn->recover = 0;	/* successful transfer, reset recover count */
727
728	if (pdu->pdu.OpcodeSpecific[0]) {	/* Response */
729		req_ccb->status = ISCSI_STATUS_TARGET_FAILURE;
730	} else {
731		switch (pdu->pdu.OpcodeSpecific[1]) {	/* Status */
732		case 0x00:
733			/* success */
734			break;
735
736		case 0x02:
737			req_ccb->status = ISCSI_STATUS_CHECK_CONDITION;
738			break;
739
740		case 0x08:
741			req_ccb->status = ISCSI_STATUS_TARGET_BUSY;
742			break;
743
744		default:
745			req_ccb->status = ISCSI_STATUS_TARGET_ERROR;
746			break;
747		}
748	}
749
750	if (pdu->pdu.Flags & (FLAG_OVERFLOW | FLAG_UNDERFLOW))
751		req_ccb->residual = ntohl(pdu->pdu.p.response.ResidualCount);
752
753	done = req_ccb->status || sn_empty(&req_ccb->DataSN_buf);
754
755	DEBC(conn, 10, ("Rx Command Response rsp = %x, status = %x\n",
756			pdu->pdu.OpcodeSpecific[0], pdu->pdu.OpcodeSpecific[1]));
757
758	rc = check_StatSN(conn, pdu->pdu.p.response.StatSN, done);
759
760	if (done)
761		wake_ccb(req_ccb);
762
763	return rc;
764}
765
766
767/*
768 * receive_asynch_pdu
769 *    Handle receipt of an asynchronous message PDU.
770 *
771 *    Parameter:
772 *          conn     The connection
773 *          pdu      The PDU
774 */
775
776STATIC int
777receive_asynch_pdu(connection_t *conn, pdu_t *pdu)
778{
779
780	DEBOUT(("Received Asynch PDU, Event %d\n", pdu->pdu.p.asynch.AsyncEvent));
781
782	switch (pdu->pdu.p.asynch.AsyncEvent) {
783	case 0:		   		/* SCSI Asynch event. Don't know what to do with it... */
784		break;
785
786	case 1:		   		/* Target requests logout. */
787		if (conn->session->active_connections > 1) {
788			kill_connection(conn, ISCSI_STATUS_TARGET_LOGOUT,
789						LOGOUT_CONNECTION, FALSE);
790		} else {
791			kill_session(conn->session, ISCSI_STATUS_TARGET_LOGOUT,
792						 LOGOUT_SESSION, FALSE);
793		}
794		break;
795
796	case 2:				/* Target is dropping connection */
797		conn = find_connection(conn->session,
798					ntohs(pdu->pdu.p.asynch.Parameter1));
799		if (conn != NULL) {
800			conn->Time2Wait = ntohs(pdu->pdu.p.asynch.Parameter2);
801			conn->Time2Retain = ntohs(pdu->pdu.p.asynch.Parameter3);
802			kill_connection(conn, ISCSI_STATUS_TARGET_DROP,
803					NO_LOGOUT, TRUE);
804		}
805		break;
806
807	case 3:				/* Target is dropping all connections of session */
808		conn->session->DefaultTime2Wait = ntohs(pdu->pdu.p.asynch.Parameter2);
809		conn->session->DefaultTime2Retain = ntohs(pdu->pdu.p.asynch.Parameter3);
810		kill_session(conn->session, ISCSI_STATUS_TARGET_DROP, NO_LOGOUT, TRUE);
811		break;
812
813	case 4:				/* Target requests parameter negotiation */
814		start_text_negotiation(conn);
815		break;
816
817	default:
818		/* ignore */
819		break;
820	}
821	return 0;
822}
823
824
825/*
826 * receive_reject_pdu
827 *    Handle receipt of a reject PDU.
828 *
829 *    Parameter:
830 *          conn     The connection
831 *          pdu      The PDU
832 */
833
834STATIC int
835receive_reject_pdu(connection_t *conn, pdu_t *pdu)
836{
837	pdu_header_t *hpdu;
838	ccb_t *req_ccb;
839
840	DEBOUT(("Received Reject PDU, reason = %x, data_len = %d\n",
841			pdu->pdu.OpcodeSpecific[0], pdu->temp_data_len));
842
843	if (pdu->temp_data_len >= BHS_SIZE) {
844		hpdu = (pdu_header_t *) pdu->temp_data;
845		req_ccb = ccb_from_itt(conn, hpdu->InitiatorTaskTag);
846
847		DEBC(conn, 9, ("Reject PDU ITT (ccb)= %x (%p)\n",
848				hpdu->InitiatorTaskTag, req_ccb));
849		if (!req_ccb) {
850			return 0;
851		}
852		switch (pdu->pdu.OpcodeSpecific[0]) {
853		case REJECT_DIGEST_ERROR:
854			/* don't retransmit data out */
855			if ((hpdu->Opcode & OPCODE_MASK) == IOP_SCSI_Data_out)
856				return 0;
857			resend_pdu(req_ccb);
858			return 0;
859
860		case REJECT_IMMED_COMMAND:
861		case REJECT_LONG_OPERATION:
862			resend_pdu(req_ccb);
863			return 0;
864
865		case REJECT_SNACK:
866		case REJECT_PROTOCOL_ERROR:
867			req_ccb->status = ISCSI_STATUS_PROTOCOL_ERROR;
868			break;
869
870		case REJECT_CMD_NOT_SUPPORTED:
871			req_ccb->status = ISCSI_STATUS_CMD_NOT_SUPPORTED;
872			break;
873
874		case REJECT_INVALID_PDU_FIELD:
875			req_ccb->status = ISCSI_STATUS_PDU_ERROR;
876			break;
877
878		default:
879			req_ccb->status = ISCSI_STATUS_GENERAL_ERROR;
880			break;
881		}
882
883		wake_ccb(req_ccb);
884		handle_connection_error(conn, ISCSI_STATUS_PROTOCOL_ERROR,
885							LOGOUT_CONNECTION);
886	}
887	return 0;
888}
889
890
891/*
892 * receive_task_management_pdu
893 *    Handle receipt of a task management PDU.
894 *
895 *    Parameter:
896 *          conn     The connection
897 *          pdu      The PDU
898 *          req_CCB  The CCB associated with the original request (if any)
899 */
900
901STATIC int
902receive_task_management_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
903{
904
905	DEBC(conn, 2, ("Received Task Management PDU, response %d, req_ccb %p\n",
906			pdu->pdu.OpcodeSpecific[0], req_ccb));
907
908	if (req_ccb != NULL) {
909		switch (pdu->pdu.OpcodeSpecific[0]) {	/* Response */
910		case 0:
911			req_ccb->status = ISCSI_STATUS_SUCCESS;
912			break;
913		case 1:
914			req_ccb->status = ISCSI_STATUS_TASK_NOT_FOUND;
915			break;
916		case 2:
917			req_ccb->status = ISCSI_STATUS_LUN_NOT_FOUND;
918			break;
919		case 3:
920			req_ccb->status = ISCSI_STATUS_TASK_ALLEGIANT;
921			break;
922		case 4:
923			req_ccb->status = ISCSI_STATUS_CANT_REASSIGN;
924			break;
925		case 5:
926			req_ccb->status = ISCSI_STATUS_FUNCTION_UNSUPPORTED;
927			break;
928		case 6:
929			req_ccb->status = ISCSI_STATUS_FUNCTION_NOT_AUTHORIZED;
930			break;
931		case 255:
932			req_ccb->status = ISCSI_STATUS_FUNCTION_REJECTED;
933			break;
934		default:
935			req_ccb->status = ISCSI_STATUS_UNKNOWN_REASON;
936			break;
937		}
938		wake_ccb(req_ccb);
939	}
940
941	check_StatSN(conn, pdu->pdu.p.task_rsp.StatSN, TRUE);
942
943	return 0;
944}
945
946
947/*
948 * receive_nop_in_pdu
949 *    Handle receipt of a Nop-In PDU.
950 *
951 *    Parameter:
952 *          conn     The connection
953 *          pdu      The PDU
954 *          req_CCB  The CCB associated with the original request (if any)
955 */
956
957STATIC int
958receive_nop_in_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
959{
960	DEBC(conn, 10,
961		("Received NOP-In PDU, req_ccb=%p, ITT=%x, TTT=%x, StatSN=%x\n",
962		req_ccb, pdu->pdu.InitiatorTaskTag,
963		pdu->pdu.p.nop_in.TargetTransferTag,
964		ntohl(pdu->pdu.p.nop_in.StatSN)));
965
966	if (pdu->pdu.InitiatorTaskTag == 0xffffffff) {
967		/* this is a target ping - respond with a pong */
968		if (pdu->pdu.p.nop_in.TargetTransferTag != 0xffffffff)
969			send_nop_out(conn, pdu);
970
971		/*
972		   Any receive resets the connection timeout, but we got a ping, which
973		   means that it's likely the other side was waiting for something to
974		   happen on the connection. If we aren't idle, send a ping right
975		   away to synch counters (don't synch on this ping because other
976		   PDUs may be on the way).
977		 */
978		if (TAILQ_FIRST(&conn->ccbs_waiting) != NULL)
979			send_nop_out(conn, NULL);
980	} else if (req_ccb != NULL) {
981		/* this is a solicited ping, check CmdSN for lost commands */
982		/* and advance StatSN */
983		check_CmdSN(conn, pdu->pdu.p.nop_in.ExpCmdSN);
984
985		wake_ccb(req_ccb);
986
987		check_StatSN(conn, pdu->pdu.p.nop_in.StatSN, TRUE);
988	}
989
990	return 0;
991}
992
993
994/*
995 * receive_pdu
996 *    Get parameters, call the appropriate handler for a received PDU.
997 *
998 *    Parameter:
999 *          conn     The connection
1000 *          pdu      The PDU
1001 *
1002 *    Returns:    0 on success, nonzero if the connection is broken.
1003 */
1004
1005STATIC int
1006receive_pdu(connection_t *conn, pdu_t *pdu)
1007{
1008	ccb_t *req_ccb;
1009	ccb_list_t waiting;
1010	int rc;
1011	uint32_t MaxCmdSN, digest;
1012	session_t *sess = conn->session;
1013
1014	if (conn->HeaderDigest) {
1015		digest = gen_digest(&pdu->pdu, BHS_SIZE);
1016		if (digest != pdu->pdu.HeaderDigest) {
1017			DEBOUT(("Header Digest Error: comp = %08x, rx = %08x\n",
1018					digest, pdu->pdu.HeaderDigest));
1019#ifdef ISCSI_TEST_MODE
1020			test_mode_rx(conn, pdu, TEST_INVALID_HEADER_CRC);
1021#endif
1022			/* try to skip to next PDU */
1023			try_resynch_receive(conn);
1024			free_pdu(pdu);
1025			return 0;
1026		}
1027	}
1028
1029	req_ccb = ccb_from_itt(conn, pdu->pdu.InitiatorTaskTag);
1030
1031	if (req_ccb != NULL && req_ccb->data_in && req_ccb->data_len &&
1032		(pdu->pdu.Opcode & OPCODE_MASK) == TOP_SCSI_Data_in) {
1033		uint32_t dsl, offset;
1034
1035		dsl = ntoh3(pdu->pdu.DataSegmentLength);
1036		offset = ntohl(pdu->pdu.p.data_in.BufferOffset);
1037
1038		if ((offset + dsl) > req_ccb->data_len) {
1039			DEBOUT(("Received more data than requested (len %d, offset %d)\n",
1040					dsl, offset));
1041			handle_connection_error(conn, ISCSI_STATUS_TARGET_ERROR, NO_LOGOUT);
1042			return 1;
1043		}
1044		DEBC(conn, 10,
1045			("Received Data in PDU - CCB = %p, Datalen = %d, Offset = %d\n",
1046			req_ccb, dsl, offset));
1047
1048		PERF_SNAPC(req_ccb, PERF_BEGIN_PDURCVDATA);
1049		rc = read_pdu_data(pdu, req_ccb->data_ptr, offset);
1050		PERF_SNAP(req_ccb, PERF_END_PDURCVDATA);
1051	} else {
1052		rc = read_pdu_data(pdu, NULL, 0);
1053	}
1054#ifdef ISCSI_TEST_MODE
1055	if (test_mode_rx(conn, pdu, rc)) {
1056		free_pdu(pdu);
1057		return rc;
1058	}
1059#endif
1060	if (!rc && (conn->state <= ST_WINDING_DOWN ||
1061		(pdu->pdu.Opcode & OPCODE_MASK) == TOP_Logout_Response)) {
1062
1063		switch (pdu->pdu.Opcode & OPCODE_MASK) {
1064		case TOP_NOP_In:
1065			rc = receive_nop_in_pdu(conn, pdu, req_ccb);
1066			break;
1067
1068		case TOP_SCSI_Response:
1069			rc = receive_command_response_pdu(conn, pdu, req_ccb);
1070			break;
1071
1072		case TOP_SCSI_Task_Management:
1073			rc = receive_task_management_pdu(conn, pdu, req_ccb);
1074			break;
1075
1076		case TOP_Login_Response:
1077			rc = receive_login_pdu(conn, pdu, req_ccb);
1078			break;
1079
1080		case TOP_Text_Response:
1081			rc = receive_text_response_pdu(conn, pdu, req_ccb);
1082			break;
1083
1084		case TOP_SCSI_Data_in:
1085			rc = receive_data_in_pdu(conn, pdu, req_ccb);
1086			break;
1087
1088		case TOP_Logout_Response:
1089			rc = receive_logout_pdu(conn, pdu, req_ccb);
1090			break;
1091
1092		case TOP_R2T:
1093			rc = receive_r2t_pdu(conn, pdu, req_ccb);
1094			break;
1095
1096		case TOP_Asynchronous_Message:
1097			rc = receive_asynch_pdu(conn, pdu);
1098			break;
1099
1100		case TOP_Reject:
1101			rc = receive_reject_pdu(conn, pdu);
1102			break;
1103
1104		default:
1105			DEBOUT(("Received Invalid Opcode %x\n", pdu->pdu.Opcode));
1106			try_resynch_receive(conn);
1107			rc = -1;
1108			break;
1109		}
1110	}
1111
1112	free_pdu(pdu);
1113	if (rc)
1114		return rc;
1115
1116	/* MaxCmdSN and ExpCmdSN are in the same place in all received PDUs */
1117	sess->ExpCmdSN = max(sess->ExpCmdSN, ntohl(pdu->pdu.p.nop_in.ExpCmdSN));
1118	MaxCmdSN = ntohl(pdu->pdu.p.nop_in.MaxCmdSN);
1119
1120	/* received a valid frame, reset timeout */
1121
1122	SET_CONN_TIMEOUT(conn,
1123			(((pdu->pdu.Opcode & OPCODE_MASK) == TOP_NOP_In) &&
1124			(TAILQ_FIRST(&conn->ccbs_waiting) == NULL)) ?
1125			conn->idle_timeout_val : CONNECTION_TIMEOUT);
1126	conn->num_timeouts = 0;
1127
1128	/*
1129	 * Un-throttle - wakeup all CCBs waiting for MaxCmdSN to increase.
1130	 * We have to handle wait/nowait CCBs a bit differently.
1131	 */
1132	if (MaxCmdSN != sess->MaxCmdSN) {
1133		sess->MaxCmdSN = MaxCmdSN;
1134#if 0
1135/* XXX - agc */
1136		if (TAILQ_FIRST(&sess->ccbs_throttled) == NULL ||
1137			!sn_a_lt_b(sess->CmdSN, MaxCmdSN))
1138			return 0;
1139#else
1140		if (TAILQ_FIRST(&sess->ccbs_throttled) == NULL)
1141			return 0;
1142#endif
1143
1144		DEBC(conn, 1, ("Unthrottling - MaxCmdSN = %d\n", MaxCmdSN));
1145
1146		CS_BEGIN;
1147		TAILQ_INIT(&waiting);
1148		TAILQ_CONCAT(&waiting, &sess->ccbs_throttled, chain);
1149		CS_END;
1150		while ((req_ccb = TAILQ_FIRST(&waiting)) != NULL) {
1151			TAILQ_REMOVE(&waiting, req_ccb, chain);
1152			DEBC(conn, 1, ("Unthrottling - ccb = %p, disp = %d\n",
1153					req_ccb, req_ccb->disp));
1154
1155			if (req_ccb->flags & CCBF_WAITING)
1156				wakeup(req_ccb);
1157			else
1158				send_command(req_ccb, req_ccb->disp, FALSE, FALSE);
1159		}
1160	}
1161
1162	return 0;
1163}
1164
1165/*****************************************************************************/
1166
1167/*
1168 * iscsi_receive_thread
1169 *    Per connection thread handling receive data.
1170 *
1171 *    Parameter:
1172 *          conn     The connection
1173 */
1174
1175void
1176iscsi_rcv_thread(void *par)
1177{
1178	connection_t *conn = (connection_t *) par;
1179	pdu_t *pdu;
1180	size_t hlen;
1181
1182	do {
1183		while (!conn->terminating) {
1184			pdu = get_pdu(conn);
1185			pdu->uio.uio_iov = pdu->io_vec;
1186			UIO_SETUP_SYSSPACE(&pdu->uio);
1187			pdu->uio.uio_iovcnt = 1;
1188			pdu->uio.uio_rw = UIO_READ;
1189
1190			pdu->io_vec[0].iov_base = &pdu->pdu;
1191			hlen = (conn->HeaderDigest) ? BHS_SIZE + 4 : BHS_SIZE;
1192			pdu->io_vec[0].iov_len = hlen;
1193			pdu->uio.uio_resid = hlen;
1194
1195			DEBC(conn, 99, ("Receive thread waiting for data\n"));
1196			if (my_soo_read(conn, &pdu->uio, MSG_WAITALL)) {
1197				free_pdu(pdu);
1198				break;
1199			}
1200			/* Check again for header digest */
1201			/* (it may have changed during the wait) */
1202			if (hlen == BHS_SIZE && conn->HeaderDigest) {
1203				pdu->uio.uio_iov = pdu->io_vec;
1204				pdu->uio.uio_iovcnt = 1;
1205				pdu->io_vec[0].iov_base = &pdu->pdu.HeaderDigest;
1206				pdu->io_vec[0].iov_len = 4;
1207				pdu->uio.uio_resid = 4;
1208				if (my_soo_read(conn, &pdu->uio, MSG_WAITALL)) {
1209					free_pdu(pdu);
1210					break;
1211				}
1212			}
1213
1214			if (receive_pdu(conn, pdu) > 0) {
1215				break;
1216			}
1217		}
1218		if (!conn->destroy) {
1219			tsleep(conn, PRIBIO, "conn_idle", 0);
1220		}
1221	} while (!conn->destroy);
1222
1223	conn->rcvproc = NULL;
1224	DEBC(conn, 5, ("Receive thread exits\n"));
1225	kthread_exit(0);
1226}
1227