1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #pragma ident "%Z%%M% %I% %E% SMI"
28
29 /*
30 * synchronous svcadm logic
31 */
32
33 #include <locale.h>
34 #include <libintl.h>
35 #include <libscf.h>
36 #include <libscf_priv.h>
37 #include <libuutil.h>
38 #include <stddef.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <unistd.h>
43 #include <assert.h>
44 #include <errno.h>
45 #include <sys/stat.h>
46
47
48 /*
49 * Definitions from svcadm.c.
50 */
51 extern scf_handle_t *h;
52 extern ssize_t max_scf_fmri_sz;
53
54 extern void do_scfdie(int) __NORETURN;
55 extern int inst_get_state(scf_instance_t *, char *, const char *,
56 scf_propertygroup_t **);
57 extern ssize_t get_astring_prop(const scf_propertygroup_t *, const char *,
58 scf_property_t *, scf_value_t *, char *, size_t);
59 extern int get_bool_prop(scf_propertygroup_t *, const char *, uint8_t *);
60
61 #define scfdie() do_scfdie(__LINE__)
62
63 int has_potential(scf_instance_t *, int);
64
65 /*
66 * Determines if the specified instance is enabled, composing the
67 * general and general_ovr property groups. For simplicity, we map
68 * most errors to "not enabled".
69 */
70 int
is_enabled(scf_instance_t * inst)71 is_enabled(scf_instance_t *inst)
72 {
73 scf_propertygroup_t *pg;
74 uint8_t bp;
75
76 if ((pg = scf_pg_create(h)) == NULL)
77 scfdie();
78
79 if (scf_instance_get_pg(inst, SCF_PG_GENERAL_OVR, pg) == 0 &&
80 get_bool_prop(pg, SCF_PROPERTY_ENABLED, &bp) == 0) {
81 scf_pg_destroy(pg);
82 return (bp);
83 }
84
85 if (scf_instance_get_pg(inst, SCF_PG_GENERAL, pg) == 0 &&
86 get_bool_prop(pg, SCF_PROPERTY_ENABLED, &bp) == 0) {
87 scf_pg_destroy(pg);
88 return (bp);
89 }
90
91 scf_pg_destroy(pg);
92 return (B_FALSE);
93 }
94
95 /*
96 * Reads an astring property from a property group. If the named
97 * property doesn't exist, returns NULL. The result of a successful
98 * call should be freed.
99 */
100 static char *
read_astring_prop(scf_propertygroup_t * pg,scf_value_t * val,scf_property_t * prop,const char * name)101 read_astring_prop(scf_propertygroup_t *pg, scf_value_t *val,
102 scf_property_t *prop, const char *name)
103 {
104 char *value;
105 size_t value_sz;
106
107 if (scf_pg_get_property(pg, name, prop) == -1) {
108 switch (scf_error()) {
109 case SCF_ERROR_NOT_FOUND:
110 case SCF_ERROR_DELETED:
111 return (NULL);
112 default:
113 scfdie();
114 }
115 }
116
117 if (scf_property_get_value(prop, val) != 0) {
118 switch (scf_error()) {
119 case SCF_ERROR_DELETED:
120 case SCF_ERROR_NOT_FOUND:
121 case SCF_ERROR_CONSTRAINT_VIOLATED:
122 return (NULL);
123 default:
124 scfdie();
125 }
126 }
127
128 value_sz = scf_limit(SCF_LIMIT_MAX_VALUE_LENGTH);
129 if ((value = malloc(value_sz)) == NULL)
130 scfdie();
131
132 if (scf_value_get_astring(val, value, value_sz) <= 0) {
133 free(value);
134 return (NULL);
135 }
136
137 return (value);
138 }
139
140 /*
141 * Creates and returns an scf_iter for the values of the named
142 * multi-value property. Returns NULL on failure.
143 */
144 static scf_iter_t *
prop_walk_init(scf_propertygroup_t * pg,const char * name)145 prop_walk_init(scf_propertygroup_t *pg, const char *name)
146 {
147 scf_iter_t *iter;
148 scf_property_t *prop;
149
150 if ((iter = scf_iter_create(h)) == NULL ||
151 (prop = scf_property_create(h)) == NULL)
152 scfdie();
153
154 if (scf_pg_get_property(pg, name, prop) != 0) {
155 switch (scf_error()) {
156 case SCF_ERROR_NOT_FOUND:
157 case SCF_ERROR_DELETED:
158 goto error;
159 default:
160 scfdie();
161 }
162 }
163
164 if (scf_iter_property_values(iter, prop) != 0) {
165 if (scf_error() != SCF_ERROR_DELETED)
166 scfdie();
167 goto error;
168 }
169
170 scf_property_destroy(prop);
171 return (iter);
172 error:
173 scf_property_destroy(prop);
174 scf_iter_destroy(iter);
175 return (NULL);
176 }
177
178 /*
179 * Reads the next value from the multi-value property using the
180 * scf_iter obtained by prop_walk_init, and places it in the buffer
181 * pointed to by fmri. Returns -1 on failure, 0 when done, and non-0
182 * when returning a value.
183 */
184 static int
prop_walk_step(scf_iter_t * iter,char * fmri,size_t len)185 prop_walk_step(scf_iter_t *iter, char *fmri, size_t len)
186 {
187 int r;
188 scf_value_t *val;
189
190 if ((val = scf_value_create(h)) == NULL)
191 scfdie();
192
193 r = scf_iter_next_value(iter, val);
194 if (r == 0)
195 goto out;
196 if (r == -1) {
197 if (scf_error() != SCF_ERROR_DELETED)
198 scfdie();
199 goto out;
200 }
201 if (scf_value_get_astring(val, fmri, len) <= 0) {
202 r = -1;
203 goto out;
204 }
205
206 out:
207 scf_value_destroy(val);
208 return (r);
209 }
210
211 /*
212 * Determines if a file dependency is satisfied, taking into account
213 * whether it is an exclusion dependency or not. If we can't access
214 * the file, we err on the side of caution and assume the dependency
215 * isn't satisfied.
216 */
217 static int
file_has_potential(char * fmri,int exclude)218 file_has_potential(char *fmri, int exclude)
219 {
220 const char *path;
221 struct stat st;
222
223 int good = exclude ? B_FALSE : B_TRUE;
224
225 if (scf_parse_file_fmri(fmri, NULL, &path) != 0)
226 return (good);
227
228 if (stat(path, &st) == 0)
229 return (good);
230
231 if (errno == EACCES) {
232 uu_warn(gettext("Unable to access \"%s\".\n"), path);
233 return (B_FALSE);
234 }
235
236 return (!good);
237 }
238
239 /*
240 * Determines if a dependency on a service instance is satisfiable.
241 * Returns 0 if not, 1 if it is, or 2 if it is an optional or exclude
242 * dependency and the service only "weakly" satisfies (i.e. is disabled
243 * or is in maintenance state).
244 */
245 static int
inst_has_potential(scf_instance_t * inst,int enabled,int optional,int exclude)246 inst_has_potential(scf_instance_t *inst, int enabled, int optional, int exclude)
247 {
248 char state[MAX_SCF_STATE_STRING_SZ];
249
250 if (!enabled)
251 return ((optional || exclude) ? 2 : 0);
252
253 /*
254 * Normally we would return a positive value on failure;
255 * relying on startd to place the service in maintenance. But
256 * if we can't read a service's state, we have to assume it is
257 * out to lunch.
258 */
259 if (inst_get_state(inst, state, NULL, NULL) != 0)
260 return (0);
261
262 /*
263 * Optional dependencies which are offline always have a possibility of
264 * coming online.
265 */
266 if (optional && strcmp(state, SCF_STATE_STRING_OFFLINE) == 0)
267 return (2);
268
269 if (strcmp(state, SCF_STATE_STRING_MAINT) == 0) {
270 /*
271 * Enabled services in maintenance state satisfy
272 * optional-all dependencies.
273 */
274 return ((optional || exclude) ? 2 : 0);
275 }
276
277 /*
278 * We're enabled and not in maintenance.
279 */
280 if (exclude)
281 return (0);
282
283 if (strcmp(state, SCF_STATE_STRING_ONLINE) == 0 ||
284 strcmp(state, SCF_STATE_STRING_DEGRADED) == 0)
285 return (1);
286
287 return (has_potential(inst, B_FALSE));
288 }
289
290 /*
291 * Determines if a dependency on an fmri is satisfiable, handling the
292 * separate cases for file, service, and instance fmris. Returns false
293 * if not, or true if it is. Takes into account if the dependency is
294 * an optional or exclusive one.
295 */
296 static int
fmri_has_potential(char * fmri,int isfile,int optional,int exclude,int restarter)297 fmri_has_potential(char *fmri, int isfile, int optional, int exclude,
298 int restarter)
299 {
300 scf_instance_t *inst;
301 scf_service_t *svc;
302 scf_iter_t *iter;
303 int good = exclude ? B_FALSE : B_TRUE;
304 int enabled;
305 int r, result;
306 int optbad;
307
308 assert(!optional || !exclude);
309
310 if (isfile)
311 return (file_has_potential(fmri, exclude));
312
313 if ((inst = scf_instance_create(h)) == NULL ||
314 (svc = scf_service_create(h)) == NULL ||
315 (iter = scf_iter_create(h)) == NULL)
316 scfdie();
317
318 if (scf_handle_decode_fmri(h, fmri, NULL, NULL, inst, NULL, NULL,
319 SCF_DECODE_FMRI_EXACT) == 0) {
320 enabled = is_enabled(inst);
321 result =
322 (inst_has_potential(inst, enabled, optional, exclude) != 0);
323 goto out;
324 }
325
326 if (scf_handle_decode_fmri(h, fmri, NULL, svc, NULL, NULL, NULL,
327 SCF_DECODE_FMRI_EXACT) != 0) {
328 /*
329 * If we are checking a restarter dependency, a bad
330 * or nonexistent service will never be noticed.
331 */
332 result = restarter ? B_FALSE : good;
333 goto out;
334 }
335
336 if (scf_iter_service_instances(iter, svc) != 0) {
337 if (scf_error() != SCF_ERROR_DELETED)
338 scfdie();
339 result = good;
340 goto out;
341 }
342
343 optbad = 0;
344 for (;;) {
345 r = scf_iter_next_instance(iter, inst);
346 if (r == 0) {
347 result = exclude || (optional && !optbad);
348 goto out;
349 }
350 if (r == -1) {
351 if (scf_error() != SCF_ERROR_DELETED)
352 scfdie();
353 result = good;
354 goto out;
355 }
356
357 enabled = is_enabled(inst);
358 r = inst_has_potential(inst, enabled, optional, exclude);
359
360 /*
361 * Exclusion dependencies over services map to
362 * require-none for its instances.
363 */
364 if (exclude)
365 r = (r == 0);
366
367 if (r == 1) {
368 /*
369 * Remember, if this is an exclusion dependency
370 * (which means we are here because there
371 * exists an instance which wasn't satisfiable
372 * in that regard), good means bad.
373 */
374 result = good;
375 goto out;
376 }
377
378 if (optional && r == 0)
379 optbad = 1;
380 }
381
382 out:
383 scf_instance_destroy(inst);
384 scf_service_destroy(svc);
385 scf_iter_destroy(iter);
386 return (result);
387 }
388
389 static int
eval_require_any(scf_iter_t * iter,char * value,size_t value_sz,int isfile)390 eval_require_any(scf_iter_t *iter, char *value, size_t value_sz, int isfile)
391 {
392 int r, empty = B_TRUE;
393
394 for (;;) {
395 /*
396 * For reasons unknown, an empty require_any dependency
397 * group is considered by startd to be satisfied.
398 * This insanity fortunately doesn't extend to
399 * dependencies on services with no instances.
400 */
401 if ((r = prop_walk_step(iter, value, value_sz)) <= 0)
402 return ((r == 0 && empty) ? B_TRUE : r);
403 if (fmri_has_potential(value, isfile, B_FALSE, B_FALSE,
404 B_FALSE))
405 return (1);
406 empty = B_FALSE;
407 }
408 }
409
410 static int
eval_all(scf_iter_t * iter,char * value,size_t value_sz,int isfile,int optional,int exclude)411 eval_all(scf_iter_t *iter, char *value, size_t value_sz,
412 int isfile, int optional, int exclude)
413 {
414 int r;
415
416 for (;;) {
417 if ((r = prop_walk_step(iter, value, value_sz)) <= 0)
418 return ((r == 0) ? 1 : r);
419 if (!fmri_has_potential(value, isfile, optional, exclude,
420 B_FALSE))
421 return (0);
422 }
423 }
424
425 static int
eval_require_all(scf_iter_t * iter,char * value,size_t value_sz,int isfile)426 eval_require_all(scf_iter_t *iter, char *value, size_t value_sz, int isfile)
427 {
428 return (eval_all(iter, value, value_sz, isfile, B_FALSE, B_FALSE));
429 }
430
431 static int
eval_optional_all(scf_iter_t * iter,char * value,size_t value_sz,int isfile)432 eval_optional_all(scf_iter_t *iter, char *value, size_t value_sz, int isfile)
433 {
434 return (eval_all(iter, value, value_sz, isfile, B_TRUE, B_FALSE));
435 }
436
437 static int
eval_exclude_all(scf_iter_t * iter,char * value,size_t value_sz,int isfile)438 eval_exclude_all(scf_iter_t *iter, char *value, size_t value_sz, int isfile)
439 {
440 return (eval_all(iter, value, value_sz, isfile, B_FALSE, B_TRUE));
441 }
442
443 /*
444 * Examines the state and health of an instance's restarter and
445 * dependencies, and determines the impact of both on the instance's
446 * ability to be brought on line. A true return value indicates that
447 * instance appears to be a likely candidate for the online club.
448 * False indicates that there is no hope for the instance.
449 */
450 int
has_potential(scf_instance_t * inst,int restarter_only)451 has_potential(scf_instance_t *inst, int restarter_only)
452 {
453 scf_snapshot_t *snap;
454 scf_iter_t *iter, *viter = NULL;
455 scf_propertygroup_t *pg;
456 scf_property_t *prop;
457 scf_value_t *val;
458 char *type = NULL, *grouping = NULL;
459 char *value;
460 size_t value_sz;
461 int result = B_TRUE, r;
462 int isfile;
463
464 value_sz = scf_limit(SCF_LIMIT_MAX_VALUE_LENGTH);
465 if ((iter = scf_iter_create(h)) == NULL ||
466 (snap = scf_snapshot_create(h)) == NULL ||
467 (pg = scf_pg_create(h)) == NULL ||
468 (val = scf_value_create(h)) == NULL ||
469 (prop = scf_property_create(h)) == NULL ||
470 (value = malloc(value_sz)) == NULL)
471 scfdie();
472
473 /*
474 * First we check our restarter as an implicit dependency.
475 */
476 if (scf_instance_get_pg_composed(inst, NULL, SCF_PG_GENERAL, pg) != 0)
477 scfdie();
478
479 r = get_astring_prop(pg, SCF_PROPERTY_RESTARTER, prop, val, value,
480 value_sz);
481 if (r == -ENOENT) {
482 (void) strlcpy(value, SCF_SERVICE_STARTD, value_sz);
483 } else if (r < 0 || r > max_scf_fmri_sz) {
484 /*
485 * Normally we would return true and let the restarter
486 * tell our caller there is a problem by changing the
487 * instance's state, but that's not going to happen if
488 * the restarter is invalid.
489 */
490 result = B_FALSE;
491 goto out;
492 }
493
494 if (!fmri_has_potential(value, B_FALSE, B_FALSE, B_FALSE, B_TRUE)) {
495 result = B_FALSE;
496 goto out;
497 }
498
499 if (restarter_only)
500 goto out;
501
502 /*
503 * Now we check explicit dependencies.
504 */
505 if (scf_instance_get_snapshot(inst, "running", snap) != 0) {
506 if (scf_error() != SCF_ERROR_NOT_FOUND)
507 scfdie();
508 scf_snapshot_destroy(snap);
509 snap = NULL;
510 }
511
512 if (scf_iter_instance_pgs_typed_composed(iter, inst, snap,
513 SCF_GROUP_DEPENDENCY) != 0) {
514 if (scf_error() != SCF_ERROR_DELETED)
515 scfdie();
516 goto out;
517 }
518
519 for (;;) {
520 r = scf_iter_next_pg(iter, pg);
521 if (r == 0)
522 break;
523 if (r == -1) {
524 if (scf_error() != SCF_ERROR_DELETED)
525 scfdie();
526 goto out;
527 }
528
529 if ((grouping = read_astring_prop(pg, val, prop,
530 SCF_PROPERTY_GROUPING)) == NULL)
531 goto out;
532
533 if ((type = read_astring_prop(pg, val, prop,
534 SCF_PROPERTY_TYPE)) == NULL)
535 goto out;
536
537 if (strcmp(type, "path") == 0) {
538 isfile = B_TRUE;
539 } else if (strcmp(type, "service") == 0) {
540 isfile = B_FALSE;
541 } else {
542 free(type);
543 goto out;
544 }
545 free(type);
546
547 if ((viter = prop_walk_init(pg, SCF_PROPERTY_ENTITIES)) == NULL)
548 goto out;
549
550 if (strcmp(grouping, SCF_DEP_REQUIRE_ALL) == 0) {
551 r = eval_require_all(viter, value, value_sz, isfile);
552 } else if (strcmp(grouping, SCF_DEP_REQUIRE_ANY) == 0) {
553 r = eval_require_any(viter, value, value_sz, isfile);
554 } else if (strcmp(grouping, SCF_DEP_EXCLUDE_ALL) == 0) {
555 r = eval_exclude_all(viter, value, value_sz, isfile);
556 } else if (strcmp(grouping, SCF_DEP_OPTIONAL_ALL) == 0) {
557 r = eval_optional_all(viter, value, value_sz, isfile);
558 } else {
559 scf_iter_destroy(viter);
560 free(grouping);
561 grouping = NULL;
562 goto out;
563 }
564
565 scf_iter_destroy(viter);
566 free(grouping);
567 grouping = NULL;
568
569 if (r == 0) {
570 result = B_FALSE;
571 goto out;
572 } else if (r == -1) {
573 goto out;
574 }
575 }
576
577 out:
578 free(value);
579 scf_property_destroy(prop);
580 scf_value_destroy(val);
581 scf_pg_destroy(pg);
582 if (snap != NULL)
583 scf_snapshot_destroy(snap);
584 if (grouping != NULL)
585 free(grouping);
586 scf_iter_destroy(iter);
587 return (result);
588 }
589