xref: /freebsd/usr.sbin/nscd/mp_rs_query.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
1 /*-
2  * Copyright (c) 2005 Michael Bushkov <bushman@rsu.ru>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  */
27 
28 #include <sys/cdefs.h>
29 #include <sys/types.h>
30 #include <sys/event.h>
31 #include <sys/socket.h>
32 #include <sys/time.h>
33 
34 #include <assert.h>
35 #include <errno.h>
36 #include <nsswitch.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 
41 #include "cachelib.h"
42 #include "config.h"
43 #include "debug.h"
44 #include "log.h"
45 #include "query.h"
46 #include "mp_rs_query.h"
47 #include "mp_ws_query.h"
48 #include "singletons.h"
49 
50 static int on_mp_read_session_close_notification(struct query_state *);
51 static void on_mp_read_session_destroy(struct query_state *);
52 static int on_mp_read_session_mapper(struct query_state *);
53 /* int on_mp_read_session_request_read1(struct query_state *); */
54 static int on_mp_read_session_request_read2(struct query_state *);
55 static int on_mp_read_session_request_process(struct query_state *);
56 static int on_mp_read_session_response_write1(struct query_state *);
57 static int on_mp_read_session_read_request_process(struct query_state *);
58 static int on_mp_read_session_read_response_write1(struct query_state *);
59 static int on_mp_read_session_read_response_write2(struct query_state *);
60 
61 /*
62  * This function is used as the query_state's destroy_func to make the
63  * proper cleanup in case of errors.
64  */
65 static void
66 on_mp_read_session_destroy(struct query_state *qstate)
67 {
68 	TRACE_IN(on_mp_read_session_destroy);
69 	finalize_comm_element(&qstate->request);
70 	finalize_comm_element(&qstate->response);
71 
72 	if (qstate->mdata != NULL) {
73 		configuration_lock_entry(qstate->config_entry, CELT_MULTIPART);
74 		close_cache_mp_read_session(
75 	    		(cache_mp_read_session)qstate->mdata);
76 		configuration_unlock_entry(qstate->config_entry,
77 			CELT_MULTIPART);
78 	}
79 	TRACE_OUT(on_mp_read_session_destroy);
80 }
81 
82 /*
83  * The functions below are used to process multipart read session initiation
84  * requests.
85  * - on_mp_read_session_request_read1 and on_mp_read_session_request_read2 read
86  *   the request itself
87  * - on_mp_read_session_request_process processes it
88  * - on_mp_read_session_response_write1 sends the response
89  */
90 int
91 on_mp_read_session_request_read1(struct query_state *qstate)
92 {
93 	struct cache_mp_read_session_request	*c_mp_rs_request;
94 	ssize_t	result;
95 
96 	TRACE_IN(on_mp_read_session_request_read1);
97 	if (qstate->kevent_watermark == 0)
98 		qstate->kevent_watermark = sizeof(size_t);
99 	else {
100 		init_comm_element(&qstate->request,
101 	    		CET_MP_READ_SESSION_REQUEST);
102 		c_mp_rs_request = get_cache_mp_read_session_request(
103 	    		&qstate->request);
104 
105 		result = qstate->read_func(qstate,
106 	    		&c_mp_rs_request->entry_length, sizeof(size_t));
107 
108 		if (result != sizeof(size_t)) {
109 			TRACE_OUT(on_mp_read_session_request_read1);
110 			return (-1);
111 		}
112 
113 		if (BUFSIZE_INVALID(c_mp_rs_request->entry_length)) {
114 			TRACE_OUT(on_mp_read_session_request_read1);
115 			return (-1);
116 		}
117 
118 		c_mp_rs_request->entry = calloc(1,
119 			c_mp_rs_request->entry_length + 1);
120 		assert(c_mp_rs_request->entry != NULL);
121 
122 		qstate->kevent_watermark = c_mp_rs_request->entry_length;
123 		qstate->process_func = on_mp_read_session_request_read2;
124 	}
125 	TRACE_OUT(on_mp_read_session_request_read1);
126 	return (0);
127 }
128 
129 static int
130 on_mp_read_session_request_read2(struct query_state *qstate)
131 {
132 	struct cache_mp_read_session_request	*c_mp_rs_request;
133 	ssize_t	result;
134 
135 	TRACE_IN(on_mp_read_session_request_read2);
136 	c_mp_rs_request = get_cache_mp_read_session_request(&qstate->request);
137 
138 	result = qstate->read_func(qstate, c_mp_rs_request->entry,
139 		c_mp_rs_request->entry_length);
140 
141 	if (result < 0 || (size_t)result != qstate->kevent_watermark) {
142 		LOG_ERR_3("on_mp_read_session_request_read2",
143 			"read failed");
144 		TRACE_OUT(on_mp_read_session_request_read2);
145 		return (-1);
146 	}
147 
148 	qstate->kevent_watermark = 0;
149 	qstate->process_func = on_mp_read_session_request_process;
150 	TRACE_OUT(on_mp_read_session_request_read2);
151 	return (0);
152 }
153 
154 static int
155 on_mp_read_session_request_process(struct query_state *qstate)
156 {
157 	struct cache_mp_read_session_request	*c_mp_rs_request;
158 	struct cache_mp_read_session_response	*c_mp_rs_response;
159 	cache_mp_read_session	rs;
160 	cache_entry	c_entry;
161 	char	*dec_cache_entry_name;
162 
163 	char *buffer;
164 	size_t buffer_size;
165 	cache_mp_write_session ws;
166 	struct agent	*lookup_agent;
167 	struct multipart_agent *mp_agent;
168 	void *mdata;
169 	int res;
170 
171 	TRACE_IN(on_mp_read_session_request_process);
172 	init_comm_element(&qstate->response, CET_MP_READ_SESSION_RESPONSE);
173 	c_mp_rs_response = get_cache_mp_read_session_response(
174 		&qstate->response);
175 	c_mp_rs_request = get_cache_mp_read_session_request(&qstate->request);
176 
177 	qstate->config_entry = configuration_find_entry(
178 		s_configuration, c_mp_rs_request->entry);
179 	if (qstate->config_entry == NULL) {
180 		c_mp_rs_response->error_code = ENOENT;
181 
182 		LOG_ERR_2("read_session_request",
183 			"can't find configuration entry '%s'."
184 			" aborting request", c_mp_rs_request->entry);
185 		goto fin;
186 	}
187 
188 	if (qstate->config_entry->enabled == 0) {
189 		c_mp_rs_response->error_code = EACCES;
190 
191 		LOG_ERR_2("read_session_request",
192 			"configuration entry '%s' is disabled",
193 			c_mp_rs_request->entry);
194 		goto fin;
195 	}
196 
197 	if (qstate->config_entry->perform_actual_lookups != 0)
198 		dec_cache_entry_name = strdup(
199 			qstate->config_entry->mp_cache_params.cep.entry_name);
200 	else {
201 #ifdef NS_NSCD_EID_CHECKING
202 		if (check_query_eids(qstate) != 0) {
203 			c_mp_rs_response->error_code = EPERM;
204 			goto fin;
205 		}
206 #endif
207 
208 		asprintf(&dec_cache_entry_name, "%s%s", qstate->eid_str,
209 			qstate->config_entry->mp_cache_params.cep.entry_name);
210 	}
211 
212 	assert(dec_cache_entry_name != NULL);
213 
214 	configuration_lock_rdlock(s_configuration);
215 	c_entry = find_cache_entry(s_cache, dec_cache_entry_name);
216 	configuration_unlock(s_configuration);
217 
218 	if ((c_entry == INVALID_CACHE) &&
219 	   (qstate->config_entry->perform_actual_lookups != 0))
220 		c_entry = register_new_mp_cache_entry(qstate,
221 			dec_cache_entry_name);
222 
223 	free(dec_cache_entry_name);
224 
225 	if (c_entry != INVALID_CACHE_ENTRY) {
226 		configuration_lock_entry(qstate->config_entry, CELT_MULTIPART);
227 		rs = open_cache_mp_read_session(c_entry);
228 		configuration_unlock_entry(qstate->config_entry,
229 			CELT_MULTIPART);
230 
231 		if ((rs == INVALID_CACHE_MP_READ_SESSION) &&
232 		   (qstate->config_entry->perform_actual_lookups != 0)) {
233 			lookup_agent = find_agent(s_agent_table,
234 				c_mp_rs_request->entry, MULTIPART_AGENT);
235 
236 			if ((lookup_agent != NULL) &&
237 			(lookup_agent->type == MULTIPART_AGENT)) {
238 				mp_agent = (struct multipart_agent *)
239 					lookup_agent;
240 				mdata = mp_agent->mp_init_func();
241 
242 				/*
243 				 * Multipart agents read the whole snapshot
244 				 * of the data at one time.
245 				 */
246 				configuration_lock_entry(qstate->config_entry,
247 					CELT_MULTIPART);
248 				ws = open_cache_mp_write_session(c_entry);
249 				configuration_unlock_entry(qstate->config_entry,
250 					CELT_MULTIPART);
251 				if (ws != NULL) {
252 				    do {
253 					buffer = NULL;
254 					res = mp_agent->mp_lookup_func(&buffer,
255 						&buffer_size,
256 						mdata);
257 
258 					if ((res & NS_TERMINATE) &&
259 					   (buffer != NULL)) {
260 						configuration_lock_entry(
261 							qstate->config_entry,
262 						   	CELT_MULTIPART);
263 						if (cache_mp_write(ws, buffer,
264 						    buffer_size) != 0) {
265 							abandon_cache_mp_write_session(ws);
266 							ws = NULL;
267 						}
268 						configuration_unlock_entry(
269 							qstate->config_entry,
270 							CELT_MULTIPART);
271 
272 						free(buffer);
273 						buffer = NULL;
274 					} else {
275 						configuration_lock_entry(
276 							qstate->config_entry,
277 							CELT_MULTIPART);
278 						close_cache_mp_write_session(ws);
279 						configuration_unlock_entry(
280 							qstate->config_entry,
281 							CELT_MULTIPART);
282 
283 						free(buffer);
284 						buffer = NULL;
285 					}
286 				    } while ((res & NS_TERMINATE) &&
287 				    	    (ws != NULL));
288 				}
289 
290 				configuration_lock_entry(qstate->config_entry,
291 					CELT_MULTIPART);
292 				rs = open_cache_mp_read_session(c_entry);
293 				configuration_unlock_entry(qstate->config_entry,
294 					CELT_MULTIPART);
295 			}
296 		}
297 
298 		if (rs == INVALID_CACHE_MP_READ_SESSION)
299 			c_mp_rs_response->error_code = -1;
300 		else {
301 		    qstate->mdata = rs;
302 		    qstate->destroy_func = on_mp_read_session_destroy;
303 
304 		    configuration_lock_entry(qstate->config_entry,
305 			CELT_MULTIPART);
306 		    if ((qstate->config_entry->mp_query_timeout.tv_sec != 0) ||
307 		    (qstate->config_entry->mp_query_timeout.tv_usec != 0))
308 			memcpy(&qstate->timeout,
309 			    &qstate->config_entry->mp_query_timeout,
310 			    sizeof(struct timeval));
311 		    configuration_unlock_entry(qstate->config_entry,
312 			CELT_MULTIPART);
313 		}
314 	} else
315 		c_mp_rs_response->error_code = -1;
316 
317 fin:
318 	qstate->process_func = on_mp_read_session_response_write1;
319 	qstate->kevent_watermark = sizeof(int);
320 	qstate->kevent_filter = EVFILT_WRITE;
321 
322 	TRACE_OUT(on_mp_read_session_request_process);
323 	return (0);
324 }
325 
326 static int
327 on_mp_read_session_response_write1(struct query_state *qstate)
328 {
329 	struct cache_mp_read_session_response	*c_mp_rs_response;
330 	ssize_t	result;
331 
332 	TRACE_IN(on_mp_read_session_response_write1);
333 	c_mp_rs_response = get_cache_mp_read_session_response(
334 		&qstate->response);
335 	result = qstate->write_func(qstate, &c_mp_rs_response->error_code,
336 		sizeof(int));
337 
338 	if (result != sizeof(int)) {
339 		LOG_ERR_3("on_mp_read_session_response_write1",
340 			"write failed");
341 		TRACE_OUT(on_mp_read_session_response_write1);
342 		return (-1);
343 	}
344 
345 	if (c_mp_rs_response->error_code == 0) {
346 		qstate->kevent_watermark = sizeof(int);
347 		qstate->process_func = on_mp_read_session_mapper;
348 		qstate->kevent_filter = EVFILT_READ;
349 	} else {
350 		qstate->kevent_watermark = 0;
351 		qstate->process_func = NULL;
352 	}
353 	TRACE_OUT(on_mp_read_session_response_write1);
354 	return (0);
355 }
356 
357 /*
358  * Mapper function is used to avoid multiple connections for each session
359  * write or read requests. After processing the request, it does not close
360  * the connection, but waits for the next request.
361  */
362 static int
363 on_mp_read_session_mapper(struct query_state *qstate)
364 {
365 	ssize_t	result;
366 	int elem_type;
367 
368 	TRACE_IN(on_mp_read_session_mapper);
369 	if (qstate->kevent_watermark == 0) {
370 		qstate->kevent_watermark = sizeof(int);
371 	} else {
372 		result = qstate->read_func(qstate, &elem_type, sizeof(int));
373 		if (result != sizeof(int)) {
374 			LOG_ERR_3("on_mp_read_session_mapper",
375 				"read failed");
376 			TRACE_OUT(on_mp_read_session_mapper);
377 			return (-1);
378 		}
379 
380 		switch (elem_type) {
381 		case CET_MP_READ_SESSION_READ_REQUEST:
382 			qstate->kevent_watermark = 0;
383 			qstate->process_func =
384 				on_mp_read_session_read_request_process;
385 			break;
386 		case CET_MP_READ_SESSION_CLOSE_NOTIFICATION:
387 			qstate->kevent_watermark = 0;
388 			qstate->process_func =
389 				on_mp_read_session_close_notification;
390 			break;
391 		default:
392 			qstate->kevent_watermark = 0;
393 			qstate->process_func = NULL;
394 			LOG_ERR_3("on_mp_read_session_mapper",
395 				"unknown element type");
396 			TRACE_OUT(on_mp_read_session_mapper);
397 			return (-1);
398 		}
399 	}
400 	TRACE_OUT(on_mp_read_session_mapper);
401 	return (0);
402 }
403 
404 /*
405  * The functions below are used to process multipart read sessions read
406  * requests. User doesn't have to pass any kind of data, besides the
407  * request identificator itself. So we don't need any XXX_read functions and
408  * start with the XXX_process function.
409  * - on_mp_read_session_read_request_process processes it
410  * - on_mp_read_session_read_response_write1 and
411  *   on_mp_read_session_read_response_write2 sends the response
412  */
413 static int
414 on_mp_read_session_read_request_process(struct query_state *qstate)
415 {
416 	struct cache_mp_read_session_read_response	*read_response;
417 
418 	TRACE_IN(on_mp_read_session_response_process);
419 	init_comm_element(&qstate->response, CET_MP_READ_SESSION_READ_RESPONSE);
420 	read_response = get_cache_mp_read_session_read_response(
421 		&qstate->response);
422 
423 	configuration_lock_entry(qstate->config_entry, CELT_MULTIPART);
424 	read_response->error_code = cache_mp_read(
425 		(cache_mp_read_session)qstate->mdata, NULL,
426 		&read_response->data_size);
427 
428 	if (read_response->error_code == 0) {
429 		read_response->data = malloc(read_response->data_size);
430 		assert(read_response != NULL);
431 		read_response->error_code = cache_mp_read(
432 			(cache_mp_read_session)qstate->mdata,
433 	    		read_response->data,
434 			&read_response->data_size);
435 	}
436 	configuration_unlock_entry(qstate->config_entry, CELT_MULTIPART);
437 
438 	if (read_response->error_code == 0)
439 		qstate->kevent_watermark = sizeof(size_t) + sizeof(int);
440 	else
441 		qstate->kevent_watermark = sizeof(int);
442 	qstate->process_func = on_mp_read_session_read_response_write1;
443 	qstate->kevent_filter = EVFILT_WRITE;
444 
445 	TRACE_OUT(on_mp_read_session_response_process);
446 	return (0);
447 }
448 
449 static int
450 on_mp_read_session_read_response_write1(struct query_state *qstate)
451 {
452 	struct cache_mp_read_session_read_response	*read_response;
453 	ssize_t	result;
454 
455 	TRACE_IN(on_mp_read_session_read_response_write1);
456 	read_response = get_cache_mp_read_session_read_response(
457 		&qstate->response);
458 
459 	result = qstate->write_func(qstate, &read_response->error_code,
460 		sizeof(int));
461 	if (read_response->error_code == 0) {
462 		result += qstate->write_func(qstate, &read_response->data_size,
463 			sizeof(size_t));
464 		if (result < 0 || (size_t)result != qstate->kevent_watermark) {
465 			TRACE_OUT(on_mp_read_session_read_response_write1);
466 			LOG_ERR_3("on_mp_read_session_read_response_write1",
467 				"write failed");
468 			return (-1);
469 		}
470 
471 		qstate->kevent_watermark = read_response->data_size;
472 		qstate->process_func = on_mp_read_session_read_response_write2;
473 	} else {
474 		if (result < 0 || (size_t)result != qstate->kevent_watermark) {
475 			LOG_ERR_3("on_mp_read_session_read_response_write1",
476 				"write failed");
477 			TRACE_OUT(on_mp_read_session_read_response_write1);
478 			return (-1);
479 		}
480 
481 		qstate->kevent_watermark = 0;
482 		qstate->process_func = NULL;
483 	}
484 
485 	TRACE_OUT(on_mp_read_session_read_response_write1);
486 	return (0);
487 }
488 
489 static int
490 on_mp_read_session_read_response_write2(struct query_state *qstate)
491 {
492 	struct cache_mp_read_session_read_response *read_response;
493 	ssize_t	result;
494 
495 	TRACE_IN(on_mp_read_session_read_response_write2);
496 	read_response = get_cache_mp_read_session_read_response(
497 		&qstate->response);
498 	result = qstate->write_func(qstate, read_response->data,
499 		read_response->data_size);
500 	if (result < 0 || (size_t)result != qstate->kevent_watermark) {
501 		LOG_ERR_3("on_mp_read_session_read_response_write2",
502 			"write failed");
503 		TRACE_OUT(on_mp_read_session_read_response_write2);
504 		return (-1);
505 	}
506 
507 	finalize_comm_element(&qstate->request);
508 	finalize_comm_element(&qstate->response);
509 
510 	qstate->kevent_watermark = sizeof(int);
511 	qstate->process_func = on_mp_read_session_mapper;
512 	qstate->kevent_filter = EVFILT_READ;
513 
514 	TRACE_OUT(on_mp_read_session_read_response_write2);
515 	return (0);
516 }
517 
518 /*
519  * Handles session close notification by calling close_cache_mp_read_session
520  * function.
521  */
522 static int
523 on_mp_read_session_close_notification(struct query_state *qstate)
524 {
525 
526 	TRACE_IN(on_mp_read_session_close_notification);
527 	configuration_lock_entry(qstate->config_entry, CELT_MULTIPART);
528 	close_cache_mp_read_session((cache_mp_read_session)qstate->mdata);
529 	configuration_unlock_entry(qstate->config_entry, CELT_MULTIPART);
530 	qstate->mdata = NULL;
531 	qstate->kevent_watermark = 0;
532 	qstate->process_func = NULL;
533 	TRACE_OUT(on_mp_read_session_close_notification);
534 	return (0);
535 }
536