xref: /netbsd-src/sys/dev/iscsi/iscsi_rcv.c (revision 8b544d8381a8530ef7ebd6bd3642fe18258f0110)
1 /*	$NetBSD: iscsi_rcv.c,v 1.27 2024/11/03 10:50:21 mlelstv 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;
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 	rw_enter(&conn->c_sock_rw, RW_READER);
63 	if (conn->c_sock == NULL) {
64 		ret = EIO;
65 	} else {
66 		so = conn->c_sock->f_socket;
67 		if (flags & MSG_WAITALL) {
68 			flags &= ~MSG_WAITALL;
69 			do {
70 				int oresid = u->uio_resid;
71 				ret = (*so->so_receive)(so, NULL, u,
72 				   NULL, NULL, &flags);
73 				if (!ret && u->uio_resid == oresid)
74 					break;
75 			} while (!ret && u->uio_resid > 0);
76 		} else {
77 			ret = (*so->so_receive)(so, NULL, u,
78 			   NULL, NULL, &flags);
79 		}
80 	}
81 
82 	rw_exit(&conn->c_sock_rw);
83 
84 	if (ret || (flags != MSG_DONTWAIT && u->uio_resid)) {
85 		DEBC(conn, 1, ("Read failed (ret: %d, req: %zu, out: %zu)\n",
86 		               ret, resid, u->uio_resid));
87 		if (ret)
88 			handle_connection_error(conn, ISCSI_STATUS_SOCKET_ERROR,
89 						RECOVER_CONNECTION);
90 		return 1;
91 	}
92 	return 0;
93 }
94 
95 
96 /*
97  * try_resynch_receive:
98  *    Skip over everything in the socket's receive buffer, in the hope of
99  *    ending up at the start of a new PDU.
100  *
101  *    Parameter:
102  *          conn     The connection
103  */
104 
105 STATIC void
106 try_resynch_receive(connection_t *conn)
107 {
108 	uint8_t buffer[64];
109 	struct uio uio;
110 	struct iovec io_vec;
111 	int rc;
112 
113 	uio.uio_rw = UIO_READ;
114 	UIO_SETUP_SYSSPACE(&uio);
115 
116 	do {
117 		io_vec.iov_base = buffer;
118 		uio.uio_iov = &io_vec;
119 		uio.uio_iovcnt = 1;
120 		uio.uio_resid = io_vec.iov_len = sizeof(buffer);
121 
122 		rc = my_soo_read(conn, &uio, MSG_DONTWAIT);
123 		DEBC(conn, 9, ("try_resynch_receive: rc = %d, resid = %zu\n",
124 				rc, uio.uio_resid));
125 	} while (!rc && !uio.uio_resid);
126 }
127 
128 
129 /*
130  * ccb_from_itt
131  *    Translate ITT into CCB pointer.
132  *
133  *    Parameter:
134  *          conn     The connection
135  *          itt      The Initiator Task Tag
136  *
137  *    Returns:
138  *          Pointer to CCB, or NULL if ITT is not a valid CCB index.
139  */
140 
141 STATIC ccb_t *
142 ccb_from_itt(connection_t *conn, uint32_t itt)
143 {
144 	ccb_t *ccb;
145 	int cidx;
146 
147 	if (itt == 0xffffffff)
148 		return NULL;
149 
150 	cidx = itt & 0xff;
151 	if (cidx >= CCBS_PER_SESSION)
152 		return NULL;
153 
154 	ccb = &conn->c_session->s_ccb[cidx];
155 
156 	if (ccb->ccb_ITT != itt) {
157 		DEBC(conn, 0,
158 		     ("ccb_from_itt: received invalid CCB itt %08x != %08x\n",
159 		      itt, ccb->ccb_ITT));
160 		return NULL;
161 	}
162 
163 	if (ccb->ccb_disp <= CCBDISP_BUSY) {
164 		DEBC(conn, 0,
165 		     ("ccb_from_itt: received CCB with invalid disp %d\n",
166 		      ccb->ccb_disp));
167 		return NULL;
168 	}
169 
170 	return ccb;
171 }
172 
173 
174 /*
175  * read_pdu_data:
176  *    Initialize the uio structure for receiving everything after the
177  *    header, including data (if present), and padding. Read the data.
178  *
179  *    Parameter:
180  *          pdu      The PDU
181  *          data     Pointer to data (may be NULL for auto-allocation)
182  *          offset   The offset into the data pointer
183  *
184  *    Returns:     0 on success
185  *                 1 if an error occurs during read
186  *                -1 if the data digest was incorrect (PDU must be ignored)
187  */
188 
189 STATIC int
190 read_pdu_data(pdu_t *pdu, uint8_t *data, uint32_t offset)
191 {
192 	static uint8_t pad_bytes[4];
193 	uint32_t len, digest;
194 	struct uio *uio;
195 	int i, pad;
196 	connection_t *conn = pdu->pdu_connection;
197 
198 	DEB(15, ("read_pdu_data: data segment length = %d\n",
199 		ntoh3(pdu->pdu_hdr.pduh_DataSegmentLength)));
200 	if (!(len = ntoh3(pdu->pdu_hdr.pduh_DataSegmentLength))) {
201 		return 0;
202 	}
203 	pad = len & 0x03;
204 	if (pad) {
205 		pad = 4 - pad;
206 	}
207 
208 	KASSERT(data != NULL || offset == 0);
209 
210 	if (data == NULL) {
211 		/*
212 		 * NOTE: Always allocate 2 extra bytes when reading temp data,
213 		 * since temp data is mostly used for received text, and we can
214 		 * make sure there's a double zero at the end of the data to mark EOF.
215 		 */
216 		if ((data = (uint8_t *) malloc(len + 2, M_TEMP, M_WAITOK)) == NULL) {
217 			DEBOUT(("ran out of mem on receive\n"));
218 			handle_connection_error(pdu->pdu_connection,
219 				ISCSI_STATUS_NO_RESOURCES, LOGOUT_SESSION);
220 			return 1;
221 		}
222 		pdu->pdu_temp_data = data;
223 		pdu->pdu_temp_data_len = len;
224 	}
225 
226 	pdu->pdu_io_vec[0].iov_base = data + offset;
227 	pdu->pdu_io_vec[0].iov_len = len;
228 
229 	uio = &pdu->pdu_uio;
230 
231 	uio->uio_iov = pdu->pdu_io_vec;
232 	uio->uio_iovcnt = 1;
233 	uio->uio_rw = UIO_READ;
234 	uio->uio_resid = len;
235 	UIO_SETUP_SYSSPACE(uio);
236 
237 	if (pad) {
238 		uio->uio_iovcnt++;
239 		uio->uio_iov[1].iov_base = pad_bytes;
240 		uio->uio_iov[1].iov_len = pad;
241 		uio->uio_resid += pad;
242 	}
243 
244 	if (conn->c_DataDigest) {
245 		i = uio->uio_iovcnt++;
246 		pdu->pdu_io_vec[i].iov_base = &pdu->pdu_data_digest;
247 		pdu->pdu_io_vec[i].iov_len = 4;
248 		uio->uio_resid += 4;
249 	}
250 
251 	/* get the data */
252 	if (my_soo_read(conn, &pdu->pdu_uio, MSG_WAITALL) != 0) {
253 		return 1;
254 	}
255 	if (conn->c_DataDigest) {
256 		digest = gen_digest_2(data, len, pad_bytes, pad);
257 
258 		if (digest != pdu->pdu_data_digest) {
259 			DEBOUT(("Data Digest Error: comp = %08x, rx = %08x\n",
260 					digest, pdu->pdu_data_digest));
261 			switch (pdu->pdu_hdr.pduh_Opcode & OPCODE_MASK) {
262 			case TOP_SCSI_Response:
263 			case TOP_Text_Response:
264 				send_snack(pdu->pdu_connection, pdu, NULL, SNACK_STATUS_NAK);
265 				break;
266 
267 			case TOP_SCSI_Data_in:
268 				send_snack(pdu->pdu_connection, pdu, NULL, SNACK_DATA_NAK);
269 				break;
270 
271 			default:
272 				/* ignore all others */
273 				break;
274 			}
275 			return -1;
276 		}
277 	}
278 	return 0;
279 }
280 
281 
282 /*
283  * collect_text_data
284  *    Handle text continuation in login and text response PDUs
285  *
286  *    Parameter:
287  *          pdu      The received PDU
288  *          req_CCB  The CCB associated with the original request
289  *
290  *    Returns:    -1    if continue flag is set
291  *                0     if text is complete
292  *                +1    if an error occurred (out of resources)
293  */
294 STATIC int
295 collect_text_data(pdu_t *pdu, ccb_t *req_ccb)
296 {
297 
298 	if (req_ccb->ccb_text_data) {
299 		int nlen;
300 		uint8_t *newp;
301 
302 		nlen = req_ccb->ccb_text_len + pdu->pdu_temp_data_len;
303 		/* Note: allocate extra 2 bytes for text terminator */
304 		if ((newp = malloc(nlen + 2, M_TEMP, M_WAITOK)) == NULL) {
305 			DEBOUT(("Collect Text Data: Out of Memory, ccb = %p\n", req_ccb));
306 			req_ccb->ccb_status = ISCSI_STATUS_NO_RESOURCES;
307 			/* XXX where is CCB freed? */
308 			return 1;
309 		}
310 		memcpy(newp, req_ccb->ccb_text_data, req_ccb->ccb_text_len);
311 		memcpy(&newp[req_ccb->ccb_text_len], pdu->pdu_temp_data, pdu->pdu_temp_data_len);
312 
313 		free(req_ccb->ccb_text_data, M_TEMP);
314 		free(pdu->pdu_temp_data, M_TEMP);
315 
316 		req_ccb->ccb_text_data = NULL;
317 		pdu->pdu_temp_data = newp;
318 		pdu->pdu_temp_data_len = nlen;
319 	}
320 
321 	if (pdu->pdu_hdr.pduh_Flags & FLAG_CONTINUE) {
322 		req_ccb->ccb_text_data = pdu->pdu_temp_data;
323 		req_ccb->ccb_text_len = pdu->pdu_temp_data_len;
324 		pdu->pdu_temp_data = NULL;
325 
326 		acknowledge_text(req_ccb->ccb_connection, pdu, req_ccb);
327 		return -1;
328 	}
329 	return 0;
330 }
331 
332 
333 /*
334  * check_StatSN
335  *    Check received vs. expected StatSN
336  *
337  *    Parameter:
338  *          conn     The connection
339  *          nw_sn    The received StatSN in network byte order
340  *          ack      Acknowledge this SN if TRUE
341  */
342 
343 STATIC int
344 check_StatSN(connection_t *conn, uint32_t nw_sn, bool ack)
345 {
346 	int rc;
347 	uint32_t sn = ntohl(nw_sn);
348 
349 	rc = add_sernum(&conn->c_StatSN_buf, sn);
350 
351 	if (ack)
352 		ack_sernum(&conn->c_StatSN_buf, sn);
353 
354 	if (rc != 1) {
355 		if (rc == 0) {
356 			DEBOUT(("Duplicate PDU, ExpSN %d, Recvd: %d\n",
357 				conn->c_StatSN_buf.ExpSN, sn));
358 			return -1;
359 		}
360 
361 		if (rc < 0) {
362 			DEBOUT(("Excessive outstanding Status PDUs, ExpSN %d, Recvd: %d\n",
363 					conn->c_StatSN_buf.ExpSN, sn));
364 			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
365 									RECOVER_CONNECTION);
366 			return rc;
367 		}
368 
369 		DEBOUT(("Missing Status PDUs: First %d, num: %d\n",
370 				conn->c_StatSN_buf.ExpSN, rc - 1));
371 		if (conn->c_state == ST_FULL_FEATURE &&
372 			conn->c_session->s_ErrorRecoveryLevel) {
373 			snack_missing(conn, NULL, SNACK_STATUS_NAK,
374 						  conn->c_StatSN_buf.ExpSN, rc - 1);
375 		} else {
376 			DEBOUT(("StatSN killing connection (State = %d, "
377 					"ErrorRecoveryLevel = %d)\n",
378 					conn->c_state, conn->c_session->s_ErrorRecoveryLevel));
379 			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
380 									RECOVER_CONNECTION);
381 			return -1;
382 		}
383 	}
384 	return 0;
385 }
386 
387 
388 /*
389  * check_CmdSN
390  *    Check received vs. expected CmdSN
391  *
392  *    Parameter:
393  *          conn     The connection
394  *          nw_sn    The received ExpCmdSN in network byte order
395  */
396 
397 STATIC void
398 check_CmdSN(connection_t *conn, uint32_t nw_sn)
399 {
400 	uint32_t sn = ntohl(nw_sn);
401 	ccb_t *ccb, *nxt;
402 
403 	TAILQ_FOREACH_SAFE(ccb, &conn->c_ccbs_waiting, ccb_chain, nxt) {
404 		DEBC(conn, 10,
405 			("CheckCmdSN - CmdSN=%d, ExpCmdSn=%d, waiting=%p, flags=%x\n",
406 			ccb->ccb_CmdSN, sn, ccb->ccb_pdu_waiting, ccb->ccb_flags));
407 		if (ccb->ccb_pdu_waiting != NULL &&
408 			sn_a_lt_b(sn, ccb->ccb_CmdSN) &&
409 			!(ccb->ccb_flags & CCBF_GOT_RSP)) {
410 			DEBC(conn, 1, ("CheckCmdSN resending - CmdSN=%d, ExpCmdSn=%d\n",
411 			               ccb->ccb_CmdSN, sn));
412 
413 			ccb->ccb_total_tries++;
414 
415 			if (++ccb->ccb_num_timeouts > MAX_CCB_TIMEOUTS ||
416 				ccb->ccb_total_tries > MAX_CCB_TRIES) {
417 				handle_connection_error(conn,
418 					ISCSI_STATUS_TIMEOUT,
419 					(ccb->ccb_total_tries <= MAX_CCB_TRIES)
420 						? RECOVER_CONNECTION
421 						: LOGOUT_CONNECTION);
422 				break;
423 			} else {
424 				resend_pdu(ccb);
425 			}
426 		}
427 
428 		/*
429 		 * The target can respond to a NOP-In before subsequent
430 		 * commands are processed. So our CmdSN can exceed the
431 		 * returned ExpCmdSN by the number of commands that are
432 		 * in flight. Adjust the expected value accordingly.
433 		 */
434 		sn++;
435 	}
436 }
437 
438 
439 /*
440  * receive_login_pdu
441  *    Handle receipt of a login response PDU.
442  *
443  *    Parameter:
444  *          conn     The connection
445  *          pdu      The PDU
446  *          req_CCB  The CCB associated with the original request (if any)
447  */
448 
449 STATIC int
450 receive_login_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
451 {
452 	int rc;
453 
454 	DEBC(conn, 9, ("Received Login Response PDU, op=%x, flags=%x, sn=%u\n",
455 			pdu->pdu_hdr.pduh_Opcode, pdu->pdu_hdr.pduh_Flags,
456 			ntohl(pdu->pdu_hdr.pduh_p.login_rsp.StatSN)));
457 
458 	if (req_ccb == NULL) {
459 		/* Duplicate?? */
460 		DEBOUT(("Received duplicate login response (no associated CCB)\n"));
461 		return -1;
462 	}
463 
464 	if (pdu->pdu_hdr.pduh_p.login_rsp.StatusClass) {
465 		DEBC(conn, 1, ("Login problem - Class = %x, Detail = %x\n",
466 				pdu->pdu_hdr.pduh_p.login_rsp.StatusClass,
467 				pdu->pdu_hdr.pduh_p.login_rsp.StatusDetail));
468 		wake_ccb(req_ccb, ISCSI_STATUS_LOGIN_FAILED);
469 		return 0;
470 	}
471 
472 	if (!conn->c_StatSN_buf.next_sn) {
473 		conn->c_StatSN_buf.next_sn = conn->c_StatSN_buf.ExpSN =
474 			ntohl(pdu->pdu_hdr.pduh_p.login_rsp.StatSN) + 1;
475 	} else if (check_StatSN(conn, pdu->pdu_hdr.pduh_p.login_rsp.StatSN, TRUE))
476 		return -1;
477 
478 	if (pdu->pdu_temp_data_len) {
479 		if ((rc = collect_text_data(pdu, req_ccb)) != 0)
480 			return max(rc, 0);
481 	}
482 
483 	negotiate_login(conn, pdu, req_ccb);
484 
485 	/* negotiate_login will decide whether login is complete or not */
486 	return 0;
487 }
488 
489 
490 /*
491  * receive_text_response_pdu
492  *    Handle receipt of a text response PDU.
493  *
494  *    Parameter:
495  *          conn     The connection
496  *          pdu      The PDU
497  *          req_CCB  The CCB associated with the original request (if any)
498  */
499 
500 STATIC int
501 receive_text_response_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
502 {
503 	int rc;
504 
505 	DEBC(conn, 9, ("Received Text Response PDU, op=%x, flags=%x\n",
506 			pdu->pdu_hdr.pduh_Opcode, pdu->pdu_hdr.pduh_Flags));
507 
508 	if (check_StatSN(conn, pdu->pdu_hdr.pduh_p.text_rsp.StatSN, TRUE)) {
509 		return -1;
510 	}
511 	if (req_ccb == NULL) {
512 		DEBOUT(("Received unsolicited text response\n"));
513 		handle_connection_error(conn, ISCSI_STATUS_TARGET_ERROR,
514 							LOGOUT_CONNECTION);
515 		return -1;
516 	}
517 
518 	if (req_ccb->ccb_pdu_waiting != NULL) {
519 		ccb_timeout_start(req_ccb, COMMAND_TIMEOUT);
520 		req_ccb->ccb_num_timeouts = 0;
521 	}
522 
523 	if ((rc = collect_text_data(pdu, req_ccb)) != 0) {
524 		return max(0, rc);
525 	}
526 	negotiate_text(conn, pdu, req_ccb);
527 
528 	return 0;
529 }
530 
531 
532 /*
533  * receive_logout_pdu
534  *    Handle receipt of a logout response PDU.
535  *
536  *    Parameter:
537  *          conn     The connection
538  *          pdu      The PDU
539  *          req_CCB  The CCB associated with the original request (if any)
540  */
541 
542 STATIC int
543 receive_logout_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
544 {
545 	bool otherconn;
546 	uint8_t response;
547 	uint32_t status;
548 
549 	otherconn = (req_ccb != NULL) ? (req_ccb->ccb_flags & CCBF_OTHERCONN) != 0 : 1;
550 	response = pdu->pdu_hdr.pduh_OpcodeSpecific [0];
551 	DEBC(conn, 1,
552 		("Received Logout PDU - CCB = %p, otherconn=%d, response=%d\n",
553 		req_ccb, otherconn, response));
554 
555 	if (req_ccb == NULL)
556 		return 0;
557 
558 	if (otherconn && check_StatSN(conn, pdu->pdu_hdr.pduh_p.logout_rsp.StatSN, TRUE))
559 		return -1;
560 
561 	switch (response) {
562 	case 0:
563 		status = ISCSI_STATUS_SUCCESS;
564 		break;
565 	case 1:
566 		status = ISCSI_STATUS_LOGOUT_CID_NOT_FOUND;
567 		break;
568 	case 2:
569 		status = ISCSI_STATUS_LOGOUT_RECOVERY_NS;
570 		break;
571 	default:
572 		status = ISCSI_STATUS_LOGOUT_ERROR;
573 		break;
574 	}
575 
576 	if (conn->c_session->s_ErrorRecoveryLevel >= 2 && response != 1) {
577 		connection_t *refconn = (otherconn) ? req_ccb->ccb_par : conn;
578 
579 		refconn->c_Time2Wait = ntohs(pdu->pdu_hdr.pduh_p.logout_rsp.Time2Wait);
580 		refconn->c_Time2Retain = ntohs(pdu->pdu_hdr.pduh_p.logout_rsp.Time2Retain);
581 	}
582 
583 	wake_ccb(req_ccb, status);
584 
585 	mutex_enter(&conn->c_lock);
586 	if (!otherconn && conn->c_state == ST_LOGOUT_SENT) {
587 		conn->c_terminating = ISCSI_STATUS_LOGOUT;
588 		conn->c_state = ST_SETTLING;
589 		conn->c_loggedout = (response) ? LOGOUT_FAILED : LOGOUT_SUCCESS;
590 		mutex_exit(&conn->c_lock);
591 
592 		connection_timeout_stop(conn);
593 
594 		/* let send thread take over next step of cleanup */
595 		mutex_enter(&conn->c_lock);
596 		cv_broadcast(&conn->c_conn_cv);
597 	}
598 	mutex_exit(&conn->c_lock);
599 
600 	return !otherconn;
601 }
602 
603 
604 /*
605  * receive_data_in_pdu
606  *    Handle receipt of a data in PDU.
607  *
608  *    Parameter:
609  *          conn     The connection
610  *          pdu      The PDU
611  *          req_CCB  The CCB associated with the original request (if any)
612  */
613 
614 STATIC int
615 receive_data_in_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
616 {
617 	uint32_t dsl, sn;
618 	bool done;
619 	int rc;
620 
621 	dsl = ntoh3(pdu->pdu_hdr.pduh_DataSegmentLength);
622 
623 	if (req_ccb == NULL || !req_ccb->ccb_data_in || !req_ccb->ccb_data_len) {
624 		DEBOUT(("Received Data In, but req_ccb not waiting for it, ignored\n"));
625 		return 0;
626 	}
627 	req_ccb->ccb_flags |= CCBF_GOT_RSP;
628 
629 	if (req_ccb->ccb_pdu_waiting != NULL) {
630 		ccb_timeout_start(req_ccb, COMMAND_TIMEOUT);
631 		req_ccb->ccb_num_timeouts = 0;
632 	}
633 
634 	sn = ntohl(pdu->pdu_hdr.pduh_p.data_in.DataSN);
635 
636 	if ((rc = add_sernum(&req_ccb->ccb_DataSN_buf, sn)) != 1) {
637 		if (!rc) {
638 			return -1;
639 		}
640 		if (rc < 0) {
641 			DEBOUT(("Excessive outstanding Data PDUs\n"));
642 			handle_connection_error(req_ccb->ccb_connection,
643 				ISCSI_STATUS_PDUS_LOST, LOGOUT_CONNECTION);
644 			return -1;
645 		}
646 		DEBOUT(("Missing Data PDUs: First %d, num: %d\n",
647 				req_ccb->ccb_DataSN_buf.ExpSN, rc - 1));
648 
649 		if (conn->c_state == ST_FULL_FEATURE &&
650 			conn->c_session->s_ErrorRecoveryLevel) {
651 			snack_missing(req_ccb->ccb_connection, req_ccb,
652 				SNACK_DATA_NAK, req_ccb->ccb_DataSN_buf.ExpSN,
653 				rc - 1);
654 		} else {
655 			DEBOUT(("Killing connection (State=%d, ErrorRecoveryLevel=%d)\n",
656 					conn->c_state, conn->c_session->s_ErrorRecoveryLevel));
657 			handle_connection_error(conn, ISCSI_STATUS_PDUS_LOST,
658 						LOGOUT_CONNECTION);
659 			return -1;
660 		}
661 	}
662 
663 	ack_sernum(&req_ccb->ccb_DataSN_buf, sn);
664 
665 	req_ccb->ccb_xfer_len += dsl;
666 
667 	if ((pdu->pdu_hdr.pduh_Flags & FLAG_ACK) && conn->c_session->s_ErrorRecoveryLevel)
668 		send_snack(conn, pdu, req_ccb, SNACK_DATA_ACK);
669 
670 	done = sn_empty(&req_ccb->ccb_DataSN_buf);
671 
672 	if (pdu->pdu_hdr.pduh_Flags & FLAG_STATUS) {
673 		DEBC(conn, 10, ("Rx Data In %d, done = %d\n",
674 			req_ccb->ccb_CmdSN, done));
675 
676 		req_ccb->ccb_flags |= CCBF_COMPLETE;
677 		/* successful transfer, reset recover count */
678 		conn->c_recover = 0;
679 
680 		if (done)
681 			wake_ccb(req_ccb, ISCSI_STATUS_SUCCESS);
682 		if (check_StatSN(conn, pdu->pdu_hdr.pduh_p.data_in.StatSN, done))
683 			return -1;
684 
685 	} else if (done && (req_ccb->ccb_flags & CCBF_COMPLETE)) {
686 		wake_ccb(req_ccb, ISCSI_STATUS_SUCCESS);
687 	}
688 	/* else wait for command response */
689 
690 	return 0;
691 }
692 
693 
694 /*
695  * receive_r2t_pdu
696  *    Handle receipt of a R2T PDU.
697  *
698  *    Parameter:
699  *          conn     The connection
700  *          pdu      The PDU
701  *          req_CCB  The CCB associated with the original request (if any)
702  */
703 
704 STATIC int
705 receive_r2t_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
706 {
707 
708 	DEBC(conn, 10, ("Received R2T PDU - CCB = %p\n", req_ccb));
709 
710 	if (req_ccb != NULL) {
711 		if (req_ccb->ccb_pdu_waiting != NULL) {
712 			ccb_timeout_start(req_ccb, COMMAND_TIMEOUT);
713 			req_ccb->ccb_num_timeouts = 0;
714 		}
715 		send_data_out(conn, pdu, req_ccb, CCBDISP_NOWAIT, TRUE);
716 	}
717 
718 	return 0;
719 }
720 
721 
722 /*
723  * receive_command_response_pdu
724  *    Handle receipt of a command response PDU.
725  *
726  *    Parameter:
727  *          conn     The connection
728  *          pdu      The PDU
729  *          req_CCB  The CCB associated with the original request (if any)
730  */
731 
732 STATIC int
733 receive_command_response_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
734 {
735 	int len, rc;
736 	bool done;
737 	uint32_t status;
738 
739 	/* Read any provided data */
740 	if (pdu->pdu_temp_data_len && req_ccb != NULL && req_ccb->ccb_sense_len_req) {
741 		len = min(req_ccb->ccb_sense_len_req,
742 				  ntohs(*((uint16_t *) pdu->pdu_temp_data)));
743 		memcpy(req_ccb->ccb_sense_ptr, ((uint16_t *) pdu->pdu_temp_data) + 1,
744 					len);
745 		req_ccb->ccb_sense_len_got = len;
746 	}
747 
748 	if (req_ccb == NULL) {
749 		/* Assume duplicate... */
750 		DEBOUT(("Possibly duplicate command response (no associated CCB)\n"));
751 		return -1;
752 	}
753 
754 	if (req_ccb->ccb_flags & CCBF_COMPLETE) {
755 		DEBOUT(("Possibly duplicate command response (tagged as COMPLETE)\n"));
756 		return -1;
757 	}
758 
759 	if (req_ccb->ccb_pdu_waiting != NULL) {
760 		ccb_timeout_start(req_ccb, COMMAND_TIMEOUT);
761 		req_ccb->ccb_num_timeouts = 0;
762 	}
763 
764 	req_ccb->ccb_flags |= CCBF_COMPLETE;
765 	conn->c_recover = 0;	/* successful transfer, reset recover count */
766 
767 	if (pdu->pdu_hdr.pduh_OpcodeSpecific[0]) {	/* Response */
768 		status = ISCSI_STATUS_TARGET_FAILURE;
769 	} else {
770 		switch (pdu->pdu_hdr.pduh_OpcodeSpecific[1]) {	/* Status */
771 		case 0x00:
772 			status = ISCSI_STATUS_SUCCESS;
773 			break;
774 
775 		case 0x02:
776 			status = ISCSI_STATUS_CHECK_CONDITION;
777 			break;
778 
779 		case 0x08:
780 			status = ISCSI_STATUS_TARGET_BUSY;
781 			break;
782 
783 		default:
784 			status = ISCSI_STATUS_TARGET_ERROR;
785 			break;
786 		}
787 	}
788 
789 	if (pdu->pdu_hdr.pduh_Flags & (FLAG_OVERFLOW | FLAG_UNDERFLOW))
790 		req_ccb->ccb_residual = ntohl(pdu->pdu_hdr.pduh_p.response.ResidualCount);
791 
792 	done = status || sn_empty(&req_ccb->ccb_DataSN_buf);
793 
794 	DEBC(conn, 10, ("Rx Response: CmdSN %d, rsp = %x, status = %x\n",
795 			req_ccb->ccb_CmdSN,
796 			pdu->pdu_hdr.pduh_OpcodeSpecific[0],
797 			pdu->pdu_hdr.pduh_OpcodeSpecific[1]));
798 
799 	rc = check_StatSN(conn, pdu->pdu_hdr.pduh_p.response.StatSN, done);
800 
801 	if (done)
802 		wake_ccb(req_ccb, status);
803 
804 	return rc;
805 }
806 
807 
808 /*
809  * receive_asynch_pdu
810  *    Handle receipt of an asynchronous message PDU.
811  *
812  *    Parameter:
813  *          conn     The connection
814  *          pdu      The PDU
815  */
816 
817 STATIC int
818 receive_asynch_pdu(connection_t *conn, pdu_t *pdu)
819 {
820 
821 	DEBOUT(("Received Asynch PDU, Event %d\n", pdu->pdu_hdr.pduh_p.asynch.AsyncEvent));
822 
823 	switch (pdu->pdu_hdr.pduh_p.asynch.AsyncEvent) {
824 	case 0:		   		/* SCSI Asynch event. Don't know what to do with it... */
825 		break;
826 
827 	case 1:	 	/* Target requests logout. */
828 		if (conn->c_session->s_active_connections > 1) {
829 			kill_connection(conn, ISCSI_STATUS_TARGET_LOGOUT,
830 						LOGOUT_CONNECTION, FALSE);
831 		} else {
832 			kill_session(conn->c_session->s_id,
833 				ISCSI_STATUS_TARGET_LOGOUT, LOGOUT_SESSION,
834 				FALSE);
835 		}
836 		break;
837 
838 	case 2:		/* Target is dropping connection */
839 		conn = find_connection(conn->c_session,
840 		    ntohs(pdu->pdu_hdr.pduh_p.asynch.Parameter1));
841 		if (conn != NULL) {
842 			conn->c_Time2Wait =
843 			    ntohs(pdu->pdu_hdr.pduh_p.asynch.Parameter2);
844 			conn->c_Time2Retain =
845 			    ntohs(pdu->pdu_hdr.pduh_p.asynch.Parameter3);
846 			kill_connection(conn, ISCSI_STATUS_TARGET_DROP,
847 					NO_LOGOUT, TRUE);
848 		}
849 		break;
850 
851 	case 3:		/* Target is dropping all connections of session */
852 		conn->c_session->s_DefaultTime2Wait =
853 		    ntohs(pdu->pdu_hdr.pduh_p.asynch.Parameter2);
854 		conn->c_session->s_DefaultTime2Retain =
855 		    ntohs(pdu->pdu_hdr.pduh_p.asynch.Parameter3);
856 		kill_session(conn->c_session->s_id,
857 			ISCSI_STATUS_TARGET_DROP, NO_LOGOUT,
858 			TRUE);
859 		break;
860 
861 	case 4:		/* Target requests parameter negotiation */
862 		start_text_negotiation(conn);
863 		break;
864 
865 	default:
866 		/* ignore */
867 		break;
868 	}
869 	return 0;
870 }
871 
872 
873 /*
874  * receive_reject_pdu
875  *    Handle receipt of a reject PDU.
876  *
877  *    Parameter:
878  *          conn     The connection
879  *          pdu      The PDU
880  */
881 
882 STATIC int
883 receive_reject_pdu(connection_t *conn, pdu_t *pdu)
884 {
885 	pdu_header_t *hpdu;
886 	ccb_t *req_ccb;
887 	uint32_t status;
888 
889 	DEBOUT(("Received Reject PDU, reason = %x, data_len = %d\n",
890 			pdu->pdu_hdr.pduh_OpcodeSpecific[0], pdu->pdu_temp_data_len));
891 
892 	if (pdu->pdu_temp_data_len >= BHS_SIZE) {
893 		hpdu = (pdu_header_t *) pdu->pdu_temp_data;
894 		req_ccb = ccb_from_itt(conn, hpdu->pduh_InitiatorTaskTag);
895 
896 		DEBC(conn, 9, ("Reject PDU ITT (ccb)= %x (%p)\n",
897 				hpdu->pduh_InitiatorTaskTag, req_ccb));
898 		if (!req_ccb) {
899 			return 0;
900 		}
901 		switch (pdu->pdu_hdr.pduh_OpcodeSpecific[0]) {
902 		case REJECT_DIGEST_ERROR:
903 			/* don't retransmit data out */
904 			if ((hpdu->pduh_Opcode & OPCODE_MASK) == IOP_SCSI_Data_out)
905 				return 0;
906 			resend_pdu(req_ccb);
907 			return 0;
908 
909 		case REJECT_IMMED_COMMAND:
910 		case REJECT_LONG_OPERATION:
911 			resend_pdu(req_ccb);
912 			return 0;
913 
914 		case REJECT_SNACK:
915 		case REJECT_PROTOCOL_ERROR:
916 			status = ISCSI_STATUS_PROTOCOL_ERROR;
917 			break;
918 
919 		case REJECT_CMD_NOT_SUPPORTED:
920 			status = ISCSI_STATUS_CMD_NOT_SUPPORTED;
921 			break;
922 
923 		case REJECT_INVALID_PDU_FIELD:
924 			status = ISCSI_STATUS_PDU_ERROR;
925 			break;
926 
927 		default:
928 			status = ISCSI_STATUS_GENERAL_ERROR;
929 			break;
930 		}
931 
932 		wake_ccb(req_ccb, status);
933 		handle_connection_error(conn, ISCSI_STATUS_PROTOCOL_ERROR,
934 							LOGOUT_CONNECTION);
935 	}
936 	return 0;
937 }
938 
939 
940 /*
941  * receive_task_management_pdu
942  *    Handle receipt of a task management PDU.
943  *
944  *    Parameter:
945  *          conn     The connection
946  *          pdu      The PDU
947  *          req_CCB  The CCB associated with the original request (if any)
948  */
949 
950 STATIC int
951 receive_task_management_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
952 {
953 	uint32_t status;
954 
955 	DEBC(conn, 2, ("Received Task Management PDU, response %d, req_ccb %p\n",
956 			pdu->pdu_hdr.pduh_OpcodeSpecific[0], req_ccb));
957 
958 	if (req_ccb != NULL) {
959 		switch (pdu->pdu_hdr.pduh_OpcodeSpecific[0]) {	/* Response */
960 		case 0:
961 			status = ISCSI_STATUS_SUCCESS;
962 			break;
963 		case 1:
964 			status = ISCSI_STATUS_TASK_NOT_FOUND;
965 			break;
966 		case 2:
967 			status = ISCSI_STATUS_LUN_NOT_FOUND;
968 			break;
969 		case 3:
970 			status = ISCSI_STATUS_TASK_ALLEGIANT;
971 			break;
972 		case 4:
973 			status = ISCSI_STATUS_CANT_REASSIGN;
974 			break;
975 		case 5:
976 			status = ISCSI_STATUS_FUNCTION_UNSUPPORTED;
977 			break;
978 		case 6:
979 			status = ISCSI_STATUS_FUNCTION_NOT_AUTHORIZED;
980 			break;
981 		case 255:
982 			status = ISCSI_STATUS_FUNCTION_REJECTED;
983 			break;
984 		default:
985 			status = ISCSI_STATUS_UNKNOWN_REASON;
986 			break;
987 		}
988 		wake_ccb(req_ccb, status);
989 	}
990 
991 	check_StatSN(conn, pdu->pdu_hdr.pduh_p.task_rsp.StatSN, TRUE);
992 
993 	return 0;
994 }
995 
996 
997 /*
998  * receive_nop_in_pdu
999  *    Handle receipt of a Nop-In PDU.
1000  *
1001  *    Parameter:
1002  *          conn     The connection
1003  *          pdu      The PDU
1004  *          req_CCB  The CCB associated with the original request (if any)
1005  */
1006 
1007 STATIC int
1008 receive_nop_in_pdu(connection_t *conn, pdu_t *pdu, ccb_t *req_ccb)
1009 {
1010 	DEBC(conn, 10,
1011 		("Received NOP_In PDU, req_ccb=%p, ITT=%x, TTT=%x, StatSN=%u\n",
1012 		req_ccb, pdu->pdu_hdr.pduh_InitiatorTaskTag,
1013 		pdu->pdu_hdr.pduh_p.nop_in.TargetTransferTag,
1014 		ntohl(pdu->pdu_hdr.pduh_p.nop_in.StatSN)));
1015 
1016 	if (pdu->pdu_hdr.pduh_InitiatorTaskTag == 0xffffffff) {
1017 		/* this is a target ping - respond with a pong */
1018 		if (pdu->pdu_hdr.pduh_p.nop_in.TargetTransferTag != 0xffffffff)
1019 			send_nop_out(conn, pdu);
1020 
1021 		/*
1022 		   Any receive resets the connection timeout, but we got a ping, which
1023 		   means that it's likely the other side was waiting for something to
1024 		   happen on the connection. If we aren't idle, send a ping right
1025 		   away to synch counters (don't synch on this ping because other
1026 		   PDUs may be on the way).
1027 		 */
1028 		if (TAILQ_FIRST(&conn->c_ccbs_waiting) != NULL)
1029 			send_nop_out(conn, NULL);
1030 	} else if (req_ccb != NULL) {
1031 		/* this is a solicited ping, check CmdSN for lost commands */
1032 		/* and advance StatSN */
1033 		check_CmdSN(conn, pdu->pdu_hdr.pduh_p.nop_in.ExpCmdSN);
1034 
1035 		wake_ccb(req_ccb, ISCSI_STATUS_SUCCESS);
1036 
1037 		check_StatSN(conn, pdu->pdu_hdr.pduh_p.nop_in.StatSN, TRUE);
1038 	} else {
1039 		DEBC(conn, 0, ("Received unsolicted NOP_In, itt=%08x\n",
1040 		               pdu->pdu_hdr.pduh_InitiatorTaskTag));
1041 	}
1042 
1043 	return 0;
1044 }
1045 
1046 
1047 /*
1048  * receive_pdu
1049  *    Get parameters, call the appropriate handler for a received PDU.
1050  *
1051  *    Parameter:
1052  *          conn     The connection
1053  *          pdu      The PDU
1054  *
1055  *    Returns:    0 on success, nonzero if the connection is broken.
1056  */
1057 
1058 STATIC int
1059 receive_pdu(connection_t *conn, pdu_t *pdu)
1060 {
1061 	ccb_t *req_ccb;
1062 	int rc;
1063 	uint32_t MaxCmdSN, ExpCmdSN, digest;
1064 	session_t *sess = conn->c_session;
1065 
1066 	if (conn->c_HeaderDigest) {
1067 		digest = gen_digest(&pdu->pdu_hdr, BHS_SIZE);
1068 		if (digest != pdu->pdu_hdr.pduh_HeaderDigest) {
1069 			DEBOUT(("Header Digest Error: comp = %08x, rx = %08x\n",
1070 					digest, pdu->pdu_hdr.pduh_HeaderDigest));
1071 			/* try to skip to next PDU */
1072 			try_resynch_receive(conn);
1073 			free_pdu(pdu);
1074 			return 0;
1075 		}
1076 	}
1077 
1078 	DEBC(conn, 10, ("Received PDU StatSN=%u, ExpCmdSN=%u MaxCmdSN=%u ExpDataSN=%u\n",
1079 	     ntohl(pdu->pdu_hdr.pduh_p.response.StatSN),
1080 	     ntohl(pdu->pdu_hdr.pduh_p.response.ExpCmdSN),
1081 	     ntohl(pdu->pdu_hdr.pduh_p.response.MaxCmdSN),
1082 	     ntohl(pdu->pdu_hdr.pduh_p.response.ExpDataSN)));
1083 
1084 	req_ccb = ccb_from_itt(conn, pdu->pdu_hdr.pduh_InitiatorTaskTag);
1085 
1086 	if (req_ccb != NULL && req_ccb->ccb_data_in && req_ccb->ccb_data_len &&
1087 		(pdu->pdu_hdr.pduh_Opcode & OPCODE_MASK) == TOP_SCSI_Data_in) {
1088 		uint32_t dsl, offset;
1089 
1090 		dsl = ntoh3(pdu->pdu_hdr.pduh_DataSegmentLength);
1091 		offset = ntohl(pdu->pdu_hdr.pduh_p.data_in.BufferOffset);
1092 
1093 		if ((offset + dsl) > req_ccb->ccb_data_len) {
1094 			DEBOUT(("Received more data than requested (len %d, offset %d)\n",
1095 					dsl, offset));
1096 			handle_connection_error(conn, ISCSI_STATUS_TARGET_ERROR, NO_LOGOUT);
1097 			return 1;
1098 		}
1099 		DEBC(conn, 10,
1100 			("Received Data in PDU - CCB = %p, Datalen = %d, Offset = %d\n",
1101 			req_ccb, dsl, offset));
1102 
1103 		rc = read_pdu_data(pdu, req_ccb->ccb_data_ptr, offset);
1104 	} else {
1105 		rc = read_pdu_data(pdu, NULL, 0);
1106 	}
1107 	if (!rc && (conn->c_state <= ST_WINDING_DOWN ||
1108 		(pdu->pdu_hdr.pduh_Opcode & OPCODE_MASK) == TOP_Logout_Response)) {
1109 
1110 		switch (pdu->pdu_hdr.pduh_Opcode & OPCODE_MASK) {
1111 		case TOP_NOP_In:
1112 			rc = receive_nop_in_pdu(conn, pdu, req_ccb);
1113 			break;
1114 
1115 		case TOP_SCSI_Response:
1116 			rc = receive_command_response_pdu(conn, pdu, req_ccb);
1117 			break;
1118 
1119 		case TOP_SCSI_Task_Management:
1120 			rc = receive_task_management_pdu(conn, pdu, req_ccb);
1121 			break;
1122 
1123 		case TOP_Login_Response:
1124 			rc = receive_login_pdu(conn, pdu, req_ccb);
1125 			break;
1126 
1127 		case TOP_Text_Response:
1128 			rc = receive_text_response_pdu(conn, pdu, req_ccb);
1129 			break;
1130 
1131 		case TOP_SCSI_Data_in:
1132 			rc = receive_data_in_pdu(conn, pdu, req_ccb);
1133 			break;
1134 
1135 		case TOP_Logout_Response:
1136 			rc = receive_logout_pdu(conn, pdu, req_ccb);
1137 			break;
1138 
1139 		case TOP_R2T:
1140 			rc = receive_r2t_pdu(conn, pdu, req_ccb);
1141 			break;
1142 
1143 		case TOP_Asynchronous_Message:
1144 			rc = receive_asynch_pdu(conn, pdu);
1145 			break;
1146 
1147 		case TOP_Reject:
1148 			rc = receive_reject_pdu(conn, pdu);
1149 			break;
1150 
1151 		default:
1152 			DEBOUT(("Received Invalid Opcode %x\n", pdu->pdu_hdr.pduh_Opcode));
1153 			try_resynch_receive(conn);
1154 			rc = -1;
1155 			break;
1156 		}
1157 	}
1158 
1159 	free_pdu(pdu);
1160 	if (rc)
1161 		return rc;
1162 
1163 	/* MaxCmdSN and ExpCmdSN are in the same place in all received PDUs */
1164 	ExpCmdSN = ntohl(pdu->pdu_hdr.pduh_p.nop_in.ExpCmdSN);
1165 	MaxCmdSN = ntohl(pdu->pdu_hdr.pduh_p.nop_in.MaxCmdSN);
1166 
1167 	/* received a valid frame, reset timeout */
1168 	conn->c_num_timeouts = 0;
1169 	if ((pdu->pdu_hdr.pduh_Opcode & OPCODE_MASK) == TOP_NOP_In &&
1170 	    TAILQ_EMPTY(&conn->c_ccbs_waiting))
1171 		connection_timeout_start(conn, conn->c_idle_timeout_val);
1172 	else
1173 		connection_timeout_start(conn, CONNECTION_TIMEOUT);
1174 
1175 	/* Update session window */
1176 	mutex_enter(&sess->s_lock);
1177 	if (sn_a_le_b(ExpCmdSN - 1, MaxCmdSN)) {
1178 		if (sn_a_lt_b(sess->s_ExpCmdSN, ExpCmdSN))
1179 			sess->s_ExpCmdSN = ExpCmdSN;
1180 		if (sn_a_lt_b(sess->s_MaxCmdSN, MaxCmdSN))
1181 			sess->s_MaxCmdSN = MaxCmdSN;
1182 	}
1183 	mutex_exit(&sess->s_lock);
1184 
1185 	return 0;
1186 }
1187 
1188 /*****************************************************************************/
1189 
1190 /*
1191  * iscsi_receive_thread
1192  *    Per connection thread handling receive data.
1193  *
1194  *    Parameter:
1195  *          conn     The connection
1196  */
1197 
1198 void
1199 iscsi_rcv_thread(void *par)
1200 {
1201 	connection_t *conn = (connection_t *) par;
1202 	pdu_t *pdu;
1203 	size_t hlen;
1204 
1205 	do {
1206 		while (!conn->c_terminating) {
1207 			pdu = get_pdu(conn, TRUE);
1208 			if (pdu == NULL) {
1209 				KASSERT(conn->c_terminating);
1210 				break;
1211 			}
1212 
1213 			pdu->pdu_uio.uio_iov = pdu->pdu_io_vec;
1214 			UIO_SETUP_SYSSPACE(&pdu->pdu_uio);
1215 			pdu->pdu_uio.uio_iovcnt = 1;
1216 			pdu->pdu_uio.uio_rw = UIO_READ;
1217 
1218 			pdu->pdu_io_vec[0].iov_base = &pdu->pdu_hdr;
1219 			hlen = (conn->c_HeaderDigest) ? BHS_SIZE + 4 : BHS_SIZE;
1220 			pdu->pdu_io_vec[0].iov_len = hlen;
1221 			pdu->pdu_uio.uio_resid = hlen;
1222 
1223 			DEBC(conn, 99, ("Receive thread waiting for data\n"));
1224 			if (my_soo_read(conn, &pdu->pdu_uio, MSG_WAITALL)) {
1225 				free_pdu(pdu);
1226 				break;
1227 			}
1228 			/* Check again for header digest */
1229 			/* (it may have changed during the wait) */
1230 			if (hlen == BHS_SIZE && conn->c_HeaderDigest) {
1231 				pdu->pdu_uio.uio_iov = pdu->pdu_io_vec;
1232 				pdu->pdu_uio.uio_iovcnt = 1;
1233 				pdu->pdu_io_vec[0].iov_base = &pdu->pdu_hdr.pduh_HeaderDigest;
1234 				pdu->pdu_io_vec[0].iov_len = 4;
1235 				pdu->pdu_uio.uio_resid = 4;
1236 				if (my_soo_read(conn, &pdu->pdu_uio, MSG_WAITALL)) {
1237 					free_pdu(pdu);
1238 					break;
1239 				}
1240 			}
1241 
1242 			if (receive_pdu(conn, pdu) > 0) {
1243 				break;
1244 			}
1245 		}
1246 		mutex_enter(&conn->c_lock);
1247 		if (!conn->c_destroy) {
1248 			cv_timedwait(&conn->c_idle_cv, &conn->c_lock, CONNECTION_IDLE_TIMEOUT);
1249 		}
1250 		mutex_exit(&conn->c_lock);
1251 	} while (!conn->c_destroy);
1252 
1253 	conn->c_rcvproc = NULL;
1254 	DEBC(conn, 5, ("Receive thread exits\n"));
1255 	kthread_exit(0);
1256 }
1257