1// SPDX-License-Identifier: GPL-2.0-or-later
2/* AFS Cache Manager Service
3 *
4 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/slab.h>
11#include <linux/sched.h>
12#include <linux/ip.h>
13#include "internal.h"
14#include "afs_cm.h"
15#include "protocol_yfs.h"
16#define RXRPC_TRACE_ONLY_DEFINE_ENUMS
17#include <trace/events/rxrpc.h>
18
19static int afs_deliver_cb_init_call_back_state(struct afs_call *);
20static int afs_deliver_cb_init_call_back_state3(struct afs_call *);
21static int afs_deliver_cb_probe(struct afs_call *);
22static int afs_deliver_cb_callback(struct afs_call *);
23static int afs_deliver_cb_probe_uuid(struct afs_call *);
24static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *);
25static void afs_cm_destructor(struct afs_call *);
26static void SRXAFSCB_CallBack(struct work_struct *);
27static void SRXAFSCB_InitCallBackState(struct work_struct *);
28static void SRXAFSCB_Probe(struct work_struct *);
29static void SRXAFSCB_ProbeUuid(struct work_struct *);
30static void SRXAFSCB_TellMeAboutYourself(struct work_struct *);
31
32static int afs_deliver_yfs_cb_callback(struct afs_call *);
33
34/*
35 * CB.CallBack operation type
36 */
37static const struct afs_call_type afs_SRXCBCallBack = {
38	.name		= "CB.CallBack",
39	.deliver	= afs_deliver_cb_callback,
40	.destructor	= afs_cm_destructor,
41	.work		= SRXAFSCB_CallBack,
42};
43
44/*
45 * CB.InitCallBackState operation type
46 */
47static const struct afs_call_type afs_SRXCBInitCallBackState = {
48	.name		= "CB.InitCallBackState",
49	.deliver	= afs_deliver_cb_init_call_back_state,
50	.destructor	= afs_cm_destructor,
51	.work		= SRXAFSCB_InitCallBackState,
52};
53
54/*
55 * CB.InitCallBackState3 operation type
56 */
57static const struct afs_call_type afs_SRXCBInitCallBackState3 = {
58	.name		= "CB.InitCallBackState3",
59	.deliver	= afs_deliver_cb_init_call_back_state3,
60	.destructor	= afs_cm_destructor,
61	.work		= SRXAFSCB_InitCallBackState,
62};
63
64/*
65 * CB.Probe operation type
66 */
67static const struct afs_call_type afs_SRXCBProbe = {
68	.name		= "CB.Probe",
69	.deliver	= afs_deliver_cb_probe,
70	.destructor	= afs_cm_destructor,
71	.work		= SRXAFSCB_Probe,
72};
73
74/*
75 * CB.ProbeUuid operation type
76 */
77static const struct afs_call_type afs_SRXCBProbeUuid = {
78	.name		= "CB.ProbeUuid",
79	.deliver	= afs_deliver_cb_probe_uuid,
80	.destructor	= afs_cm_destructor,
81	.work		= SRXAFSCB_ProbeUuid,
82};
83
84/*
85 * CB.TellMeAboutYourself operation type
86 */
87static const struct afs_call_type afs_SRXCBTellMeAboutYourself = {
88	.name		= "CB.TellMeAboutYourself",
89	.deliver	= afs_deliver_cb_tell_me_about_yourself,
90	.destructor	= afs_cm_destructor,
91	.work		= SRXAFSCB_TellMeAboutYourself,
92};
93
94/*
95 * YFS CB.CallBack operation type
96 */
97static const struct afs_call_type afs_SRXYFSCB_CallBack = {
98	.name		= "YFSCB.CallBack",
99	.deliver	= afs_deliver_yfs_cb_callback,
100	.destructor	= afs_cm_destructor,
101	.work		= SRXAFSCB_CallBack,
102};
103
104/*
105 * route an incoming cache manager call
106 * - return T if supported, F if not
107 */
108bool afs_cm_incoming_call(struct afs_call *call)
109{
110	_enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);
111
112	switch (call->operation_ID) {
113	case CBCallBack:
114		call->type = &afs_SRXCBCallBack;
115		return true;
116	case CBInitCallBackState:
117		call->type = &afs_SRXCBInitCallBackState;
118		return true;
119	case CBInitCallBackState3:
120		call->type = &afs_SRXCBInitCallBackState3;
121		return true;
122	case CBProbe:
123		call->type = &afs_SRXCBProbe;
124		return true;
125	case CBProbeUuid:
126		call->type = &afs_SRXCBProbeUuid;
127		return true;
128	case CBTellMeAboutYourself:
129		call->type = &afs_SRXCBTellMeAboutYourself;
130		return true;
131	case YFSCBCallBack:
132		if (call->service_id != YFS_CM_SERVICE)
133			return false;
134		call->type = &afs_SRXYFSCB_CallBack;
135		return true;
136	default:
137		return false;
138	}
139}
140
141/*
142 * Find the server record by peer address and record a probe to the cache
143 * manager from a server.
144 */
145static int afs_find_cm_server_by_peer(struct afs_call *call)
146{
147	struct sockaddr_rxrpc srx;
148	struct afs_server *server;
149	struct rxrpc_peer *peer;
150
151	peer = rxrpc_kernel_get_call_peer(call->net->socket, call->rxcall);
152
153	server = afs_find_server(call->net, peer);
154	if (!server) {
155		trace_afs_cm_no_server(call, &srx);
156		return 0;
157	}
158
159	call->server = server;
160	return 0;
161}
162
163/*
164 * Find the server record by server UUID and record a probe to the cache
165 * manager from a server.
166 */
167static int afs_find_cm_server_by_uuid(struct afs_call *call,
168				      struct afs_uuid *uuid)
169{
170	struct afs_server *server;
171
172	rcu_read_lock();
173	server = afs_find_server_by_uuid(call->net, call->request);
174	rcu_read_unlock();
175	if (!server) {
176		trace_afs_cm_no_server_u(call, call->request);
177		return 0;
178	}
179
180	call->server = server;
181	return 0;
182}
183
184/*
185 * Clean up a cache manager call.
186 */
187static void afs_cm_destructor(struct afs_call *call)
188{
189	kfree(call->buffer);
190	call->buffer = NULL;
191}
192
193/*
194 * Abort a service call from within an action function.
195 */
196static void afs_abort_service_call(struct afs_call *call, u32 abort_code, int error,
197				   enum rxrpc_abort_reason why)
198{
199	rxrpc_kernel_abort_call(call->net->socket, call->rxcall,
200				abort_code, error, why);
201	afs_set_call_complete(call, error, 0);
202}
203
204/*
205 * The server supplied a list of callbacks that it wanted to break.
206 */
207static void SRXAFSCB_CallBack(struct work_struct *work)
208{
209	struct afs_call *call = container_of(work, struct afs_call, work);
210
211	_enter("");
212
213	/* We need to break the callbacks before sending the reply as the
214	 * server holds up change visibility till it receives our reply so as
215	 * to maintain cache coherency.
216	 */
217	if (call->server) {
218		trace_afs_server(call->server->debug_id,
219				 refcount_read(&call->server->ref),
220				 atomic_read(&call->server->active),
221				 afs_server_trace_callback);
222		afs_break_callbacks(call->server, call->count, call->request);
223	}
224
225	afs_send_empty_reply(call);
226	afs_put_call(call);
227	_leave("");
228}
229
230/*
231 * deliver request data to a CB.CallBack call
232 */
233static int afs_deliver_cb_callback(struct afs_call *call)
234{
235	struct afs_callback_break *cb;
236	__be32 *bp;
237	int ret, loop;
238
239	_enter("{%u}", call->unmarshall);
240
241	switch (call->unmarshall) {
242	case 0:
243		afs_extract_to_tmp(call);
244		call->unmarshall++;
245
246		/* extract the FID array and its count in two steps */
247		fallthrough;
248	case 1:
249		_debug("extract FID count");
250		ret = afs_extract_data(call, true);
251		if (ret < 0)
252			return ret;
253
254		call->count = ntohl(call->tmp);
255		_debug("FID count: %u", call->count);
256		if (call->count > AFSCBMAX)
257			return afs_protocol_error(call, afs_eproto_cb_fid_count);
258
259		call->buffer = kmalloc(array3_size(call->count, 3, 4),
260				       GFP_KERNEL);
261		if (!call->buffer)
262			return -ENOMEM;
263		afs_extract_to_buf(call, call->count * 3 * 4);
264		call->unmarshall++;
265
266		fallthrough;
267	case 2:
268		_debug("extract FID array");
269		ret = afs_extract_data(call, true);
270		if (ret < 0)
271			return ret;
272
273		_debug("unmarshall FID array");
274		call->request = kcalloc(call->count,
275					sizeof(struct afs_callback_break),
276					GFP_KERNEL);
277		if (!call->request)
278			return -ENOMEM;
279
280		cb = call->request;
281		bp = call->buffer;
282		for (loop = call->count; loop > 0; loop--, cb++) {
283			cb->fid.vid	= ntohl(*bp++);
284			cb->fid.vnode	= ntohl(*bp++);
285			cb->fid.unique	= ntohl(*bp++);
286		}
287
288		afs_extract_to_tmp(call);
289		call->unmarshall++;
290
291		/* extract the callback array and its count in two steps */
292		fallthrough;
293	case 3:
294		_debug("extract CB count");
295		ret = afs_extract_data(call, true);
296		if (ret < 0)
297			return ret;
298
299		call->count2 = ntohl(call->tmp);
300		_debug("CB count: %u", call->count2);
301		if (call->count2 != call->count && call->count2 != 0)
302			return afs_protocol_error(call, afs_eproto_cb_count);
303		call->iter = &call->def_iter;
304		iov_iter_discard(&call->def_iter, ITER_DEST, call->count2 * 3 * 4);
305		call->unmarshall++;
306
307		fallthrough;
308	case 4:
309		_debug("extract discard %zu/%u",
310		       iov_iter_count(call->iter), call->count2 * 3 * 4);
311
312		ret = afs_extract_data(call, false);
313		if (ret < 0)
314			return ret;
315
316		call->unmarshall++;
317		fallthrough;
318
319	case 5:
320		break;
321	}
322
323	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
324		return afs_io_error(call, afs_io_error_cm_reply);
325
326	/* we'll need the file server record as that tells us which set of
327	 * vnodes to operate upon */
328	return afs_find_cm_server_by_peer(call);
329}
330
331/*
332 * allow the fileserver to request callback state (re-)initialisation
333 */
334static void SRXAFSCB_InitCallBackState(struct work_struct *work)
335{
336	struct afs_call *call = container_of(work, struct afs_call, work);
337
338	_enter("{%p}", call->server);
339
340	if (call->server)
341		afs_init_callback_state(call->server);
342	afs_send_empty_reply(call);
343	afs_put_call(call);
344	_leave("");
345}
346
347/*
348 * deliver request data to a CB.InitCallBackState call
349 */
350static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
351{
352	int ret;
353
354	_enter("");
355
356	afs_extract_discard(call, 0);
357	ret = afs_extract_data(call, false);
358	if (ret < 0)
359		return ret;
360
361	/* we'll need the file server record as that tells us which set of
362	 * vnodes to operate upon */
363	return afs_find_cm_server_by_peer(call);
364}
365
366/*
367 * deliver request data to a CB.InitCallBackState3 call
368 */
369static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)
370{
371	struct afs_uuid *r;
372	unsigned loop;
373	__be32 *b;
374	int ret;
375
376	_enter("");
377
378	_enter("{%u}", call->unmarshall);
379
380	switch (call->unmarshall) {
381	case 0:
382		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
383		if (!call->buffer)
384			return -ENOMEM;
385		afs_extract_to_buf(call, 11 * sizeof(__be32));
386		call->unmarshall++;
387
388		fallthrough;
389	case 1:
390		_debug("extract UUID");
391		ret = afs_extract_data(call, false);
392		switch (ret) {
393		case 0:		break;
394		case -EAGAIN:	return 0;
395		default:	return ret;
396		}
397
398		_debug("unmarshall UUID");
399		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
400		if (!call->request)
401			return -ENOMEM;
402
403		b = call->buffer;
404		r = call->request;
405		r->time_low			= b[0];
406		r->time_mid			= htons(ntohl(b[1]));
407		r->time_hi_and_version		= htons(ntohl(b[2]));
408		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
409		r->clock_seq_low		= ntohl(b[4]);
410
411		for (loop = 0; loop < 6; loop++)
412			r->node[loop] = ntohl(b[loop + 5]);
413
414		call->unmarshall++;
415		fallthrough;
416
417	case 2:
418		break;
419	}
420
421	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
422		return afs_io_error(call, afs_io_error_cm_reply);
423
424	/* we'll need the file server record as that tells us which set of
425	 * vnodes to operate upon */
426	return afs_find_cm_server_by_uuid(call, call->request);
427}
428
429/*
430 * allow the fileserver to see if the cache manager is still alive
431 */
432static void SRXAFSCB_Probe(struct work_struct *work)
433{
434	struct afs_call *call = container_of(work, struct afs_call, work);
435
436	_enter("");
437	afs_send_empty_reply(call);
438	afs_put_call(call);
439	_leave("");
440}
441
442/*
443 * deliver request data to a CB.Probe call
444 */
445static int afs_deliver_cb_probe(struct afs_call *call)
446{
447	int ret;
448
449	_enter("");
450
451	afs_extract_discard(call, 0);
452	ret = afs_extract_data(call, false);
453	if (ret < 0)
454		return ret;
455
456	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
457		return afs_io_error(call, afs_io_error_cm_reply);
458	return afs_find_cm_server_by_peer(call);
459}
460
461/*
462 * Allow the fileserver to quickly find out if the cache manager has been
463 * rebooted.
464 */
465static void SRXAFSCB_ProbeUuid(struct work_struct *work)
466{
467	struct afs_call *call = container_of(work, struct afs_call, work);
468	struct afs_uuid *r = call->request;
469
470	_enter("");
471
472	if (memcmp(r, &call->net->uuid, sizeof(call->net->uuid)) == 0)
473		afs_send_empty_reply(call);
474	else
475		afs_abort_service_call(call, 1, 1, afs_abort_probeuuid_negative);
476
477	afs_put_call(call);
478	_leave("");
479}
480
481/*
482 * deliver request data to a CB.ProbeUuid call
483 */
484static int afs_deliver_cb_probe_uuid(struct afs_call *call)
485{
486	struct afs_uuid *r;
487	unsigned loop;
488	__be32 *b;
489	int ret;
490
491	_enter("{%u}", call->unmarshall);
492
493	switch (call->unmarshall) {
494	case 0:
495		call->buffer = kmalloc_array(11, sizeof(__be32), GFP_KERNEL);
496		if (!call->buffer)
497			return -ENOMEM;
498		afs_extract_to_buf(call, 11 * sizeof(__be32));
499		call->unmarshall++;
500
501		fallthrough;
502	case 1:
503		_debug("extract UUID");
504		ret = afs_extract_data(call, false);
505		switch (ret) {
506		case 0:		break;
507		case -EAGAIN:	return 0;
508		default:	return ret;
509		}
510
511		_debug("unmarshall UUID");
512		call->request = kmalloc(sizeof(struct afs_uuid), GFP_KERNEL);
513		if (!call->request)
514			return -ENOMEM;
515
516		b = call->buffer;
517		r = call->request;
518		r->time_low			= b[0];
519		r->time_mid			= htons(ntohl(b[1]));
520		r->time_hi_and_version		= htons(ntohl(b[2]));
521		r->clock_seq_hi_and_reserved 	= ntohl(b[3]);
522		r->clock_seq_low		= ntohl(b[4]);
523
524		for (loop = 0; loop < 6; loop++)
525			r->node[loop] = ntohl(b[loop + 5]);
526
527		call->unmarshall++;
528		fallthrough;
529
530	case 2:
531		break;
532	}
533
534	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
535		return afs_io_error(call, afs_io_error_cm_reply);
536	return afs_find_cm_server_by_peer(call);
537}
538
539/*
540 * allow the fileserver to ask about the cache manager's capabilities
541 */
542static void SRXAFSCB_TellMeAboutYourself(struct work_struct *work)
543{
544	struct afs_call *call = container_of(work, struct afs_call, work);
545	int loop;
546
547	struct {
548		struct /* InterfaceAddr */ {
549			__be32 nifs;
550			__be32 uuid[11];
551			__be32 ifaddr[32];
552			__be32 netmask[32];
553			__be32 mtu[32];
554		} ia;
555		struct /* Capabilities */ {
556			__be32 capcount;
557			__be32 caps[1];
558		} cap;
559	} reply;
560
561	_enter("");
562
563	memset(&reply, 0, sizeof(reply));
564
565	reply.ia.uuid[0] = call->net->uuid.time_low;
566	reply.ia.uuid[1] = htonl(ntohs(call->net->uuid.time_mid));
567	reply.ia.uuid[2] = htonl(ntohs(call->net->uuid.time_hi_and_version));
568	reply.ia.uuid[3] = htonl((s8) call->net->uuid.clock_seq_hi_and_reserved);
569	reply.ia.uuid[4] = htonl((s8) call->net->uuid.clock_seq_low);
570	for (loop = 0; loop < 6; loop++)
571		reply.ia.uuid[loop + 5] = htonl((s8) call->net->uuid.node[loop]);
572
573	reply.cap.capcount = htonl(1);
574	reply.cap.caps[0] = htonl(AFS_CAP_ERROR_TRANSLATION);
575	afs_send_simple_reply(call, &reply, sizeof(reply));
576	afs_put_call(call);
577	_leave("");
578}
579
580/*
581 * deliver request data to a CB.TellMeAboutYourself call
582 */
583static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
584{
585	int ret;
586
587	_enter("");
588
589	afs_extract_discard(call, 0);
590	ret = afs_extract_data(call, false);
591	if (ret < 0)
592		return ret;
593
594	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
595		return afs_io_error(call, afs_io_error_cm_reply);
596	return afs_find_cm_server_by_peer(call);
597}
598
599/*
600 * deliver request data to a YFS CB.CallBack call
601 */
602static int afs_deliver_yfs_cb_callback(struct afs_call *call)
603{
604	struct afs_callback_break *cb;
605	struct yfs_xdr_YFSFid *bp;
606	size_t size;
607	int ret, loop;
608
609	_enter("{%u}", call->unmarshall);
610
611	switch (call->unmarshall) {
612	case 0:
613		afs_extract_to_tmp(call);
614		call->unmarshall++;
615
616		/* extract the FID array and its count in two steps */
617		fallthrough;
618	case 1:
619		_debug("extract FID count");
620		ret = afs_extract_data(call, true);
621		if (ret < 0)
622			return ret;
623
624		call->count = ntohl(call->tmp);
625		_debug("FID count: %u", call->count);
626		if (call->count > YFSCBMAX)
627			return afs_protocol_error(call, afs_eproto_cb_fid_count);
628
629		size = array_size(call->count, sizeof(struct yfs_xdr_YFSFid));
630		call->buffer = kmalloc(size, GFP_KERNEL);
631		if (!call->buffer)
632			return -ENOMEM;
633		afs_extract_to_buf(call, size);
634		call->unmarshall++;
635
636		fallthrough;
637	case 2:
638		_debug("extract FID array");
639		ret = afs_extract_data(call, false);
640		if (ret < 0)
641			return ret;
642
643		_debug("unmarshall FID array");
644		call->request = kcalloc(call->count,
645					sizeof(struct afs_callback_break),
646					GFP_KERNEL);
647		if (!call->request)
648			return -ENOMEM;
649
650		cb = call->request;
651		bp = call->buffer;
652		for (loop = call->count; loop > 0; loop--, cb++) {
653			cb->fid.vid	= xdr_to_u64(bp->volume);
654			cb->fid.vnode	= xdr_to_u64(bp->vnode.lo);
655			cb->fid.vnode_hi = ntohl(bp->vnode.hi);
656			cb->fid.unique	= ntohl(bp->vnode.unique);
657			bp++;
658		}
659
660		afs_extract_to_tmp(call);
661		call->unmarshall++;
662		fallthrough;
663
664	case 3:
665		break;
666	}
667
668	if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
669		return afs_io_error(call, afs_io_error_cm_reply);
670
671	/* We'll need the file server record as that tells us which set of
672	 * vnodes to operate upon.
673	 */
674	return afs_find_cm_server_by_peer(call);
675}
676