xref: /titanic_41/usr/src/lib/librestart/common/librestart.h (revision a4ca1d52cdf9b55a14d0c62ff62b74cd904110ff)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
23  */
24 
25 #ifndef	_LIBRESTART_H
26 #define	_LIBRESTART_H
27 
28 #include <libsysevent.h>
29 #include <libcontract.h>
30 #include <libscf.h>
31 #include <limits.h>
32 #include <priv.h>
33 #include <pwd.h>
34 #include <sys/types.h>
35 
36 #ifdef	__cplusplus
37 extern "C" {
38 #endif
39 
40 /*
41  * There are 3 parts to librestart.
42  *	1) The event protocol from the master restarter to its delegates.
43  *	2) A functional interface for updating the repository.
44  *	3) Convenience functions for common restarter tasks.
45  *
46  * Event protocol
47  *	We need a reliable event protocol, as there's no way to define
48  *	restarter events as idempotent.
49  *
50  *	Currently using sysevent channels as the reliable event implementation.
51  *	This could change if the implementation proves unsuitable, but
52  *	the API defined here should abstract anything but a change in
53  *	the fundamental event model.
54  *
55  *	We offer functions to tease apart the event rather than generic
56  *	nvpair interfaces. This is because each event type has a well-
57  *	defined set of fields.
58  */
59 
60 /*
61  * Some of the functions have external contracted consumers, review contracts
62  * when making incompatible changes.
63  */
64 
65 typedef struct restarter_event_handle restarter_event_handle_t;
66 typedef struct restarter_event restarter_event_t;
67 
68 typedef uint32_t restarter_event_type_t;
69 
70 /*
71  * Define an event protocol version. In theory, we could use this in
72  * the future to support delegated restarters which use an older
73  * protocol. In practice, increment RESTARTER_EVENT_VERSION whenever the
74  * protocol might have changed.
75  */
76 #define	RESTARTER_EVENT_VERSION		5
77 
78 #define	RESTARTER_FLAG_DEBUG		1
79 
80 #define	RESTARTER_ERRMSGSZ		1024
81 
82 /*
83  * Event types
84  *	RESTARTER_EVENT_TYPE_ADD_INSTANCE
85  *		responsible for a new (stopped) instance
86  *	RESTARTER_EVENT_TYPE_REMOVE_INSTANCE
87  *		no longer responsible for this instance; stop it and return
88  *	RESTARTER_EVENT_TYPE_ENABLE
89  *		no guarantee that dependencies are met; see
90  *		RESTARTER_EVENT_TYPE_START
91  *	RESTARTER_EVENT_TYPE_DISABLE
92  *		no guarantee that instance was running
93  *	RESTARTER_EVENT_TYPE_ADMIN_DEGRADED
94  *	RESTARTER_EVENT_TYPE_ADMIN_REFRESH
95  *	RESTARTER_EVENT_TYPE_ADMIN_RESTART
96  *	RESTARTER_EVENT_TYPE_ADMIN_MAINT_OFF
97  *	RESTARTER_EVENT_TYPE_ADMIN_MAINT_ON
98  *	RESTARTER_EVENT_TYPE_ADMIN_MAINT_ON_IMMEDIATE
99  *	RESTARTER_EVENT_TYPE_ADMIN_MAINT_OFF
100  *	RESTARTER_EVENT_TYPE_STOP
101  *		dependencies are, or are becoming, unsatisfied
102  *	RESTARTER_EVENT_TYPE_START
103  *		dependencies have become satisfied
104  *	RESTARTER_EVENT_TYPE_DEPENDENCY_CYCLE
105  *		instance caused a dependency cycle
106  *	RESTARTER_EVENT_TYPE_INVALID_DEPENDENCY
107  *		instance has an invalid dependency
108  */
109 
110 #define	RESTARTER_EVENT_TYPE_INVALID			0
111 #define	RESTARTER_EVENT_TYPE_ADD_INSTANCE		1
112 #define	RESTARTER_EVENT_TYPE_REMOVE_INSTANCE		2
113 #define	RESTARTER_EVENT_TYPE_ENABLE			3
114 #define	RESTARTER_EVENT_TYPE_DISABLE			4
115 #define	RESTARTER_EVENT_TYPE_ADMIN_DEGRADED		5
116 #define	RESTARTER_EVENT_TYPE_ADMIN_REFRESH		6
117 #define	RESTARTER_EVENT_TYPE_ADMIN_RESTART		7
118 #define	RESTARTER_EVENT_TYPE_ADMIN_MAINT_OFF		8
119 #define	RESTARTER_EVENT_TYPE_ADMIN_MAINT_ON		9
120 #define	RESTARTER_EVENT_TYPE_ADMIN_MAINT_ON_IMMEDIATE	10
121 #define	RESTARTER_EVENT_TYPE_STOP			11
122 #define	RESTARTER_EVENT_TYPE_START			12
123 #define	RESTARTER_EVENT_TYPE_DEPENDENCY_CYCLE		13
124 #define	RESTARTER_EVENT_TYPE_INVALID_DEPENDENCY		14
125 #define	RESTARTER_EVENT_TYPE_ADMIN_DISABLE		15
126 #define	RESTARTER_EVENT_TYPE_STOP_RESET			16
127 
128 #define	RESTARTER_EVENT_ERROR			-1
129 
130 #define	RESTARTER_EVENT_INSTANCE_DISABLED	0
131 #define	RESTARTER_EVENT_INSTANCE_ENABLED	1
132 
133 typedef enum {
134 	RESTARTER_STATE_NONE,
135 	RESTARTER_STATE_UNINIT,
136 	RESTARTER_STATE_MAINT,
137 	RESTARTER_STATE_OFFLINE,
138 	RESTARTER_STATE_DISABLED,
139 	RESTARTER_STATE_ONLINE,
140 	RESTARTER_STATE_DEGRADED
141 } restarter_instance_state_t;
142 
143 /*
144  * These values are ordered by severity of required restart, as we use
145  * integer comparisons to determine error flow.
146  */
147 typedef enum {
148 	RERR_UNSUPPORTED = -1,
149 	RERR_NONE = 0,			/* no error, restart, refresh */
150 	RERR_FAULT,			/* fault occurred */
151 	RERR_RESTART,			/* transition due to restart */
152 	RERR_REFRESH			/* transition due to refresh */
153 } restarter_error_t;
154 /*
155  * restarter_store_contract() and restarter_remove_contract() types
156  */
157 typedef enum {
158 	RESTARTER_CONTRACT_PRIMARY,
159 	RESTARTER_CONTRACT_TRANSIENT
160 } restarter_contract_type_t;
161 
162 /*
163  * restarter_bind_handle() registers a delegate with svc.startd to
164  * begin consuming events.
165  *
166  * On initial bind, the delgated restarter receives an event for each
167  * instance it is responsible for, as if that instance was new.
168  *
169  * callers must have superuser privileges
170  *
171  * The event handler can return 0 for success, or EAGAIN to request
172  * retry of event delivery. EAGAIN may be returned 3 times before the
173  * event is discarded.
174  */
175 int restarter_bind_handle(uint32_t, const char *,
176     int (*event_handler)(restarter_event_t *), int,
177     restarter_event_handle_t **);
178 
179 restarter_event_type_t restarter_event_get_type(restarter_event_t *);
180 uint64_t restarter_event_get_seq(restarter_event_t *);
181 void restarter_event_get_time(restarter_event_t *, hrtime_t *);
182 ssize_t restarter_event_get_instance(restarter_event_t *, char *, size_t);
183 restarter_event_handle_t *restarter_event_get_handle(restarter_event_t *);
184 
185 /*
186  * The following functions work only on certain types of events.
187  * They fail with a return of -1 if they're called on an inappropriate event.
188  */
189 int restarter_event_get_enabled(restarter_event_t *);
190 int restarter_event_get_current_states(restarter_event_t *,
191     restarter_instance_state_t *, restarter_instance_state_t *);
192 
193 /*
194  * State transition reasons
195  */
196 
197 typedef enum {
198 	restarter_str_none,
199 	restarter_str_administrative_request,
200 	restarter_str_bad_repo_state,
201 	restarter_str_clear_request,
202 	restarter_str_ct_ev_core,
203 	restarter_str_ct_ev_exit,
204 	restarter_str_ct_ev_hwerr,
205 	restarter_str_ct_ev_signal,
206 	restarter_str_dependencies_satisfied,
207 	restarter_str_dependency_activity,
208 	restarter_str_dependency_cycle,
209 	restarter_str_disable_request,
210 	restarter_str_enable_request,
211 	restarter_str_fault_threshold_reached,
212 	restarter_str_insert_in_graph,
213 	restarter_str_invalid_dependency,
214 	restarter_str_invalid_restarter,
215 	restarter_str_method_failed,
216 	restarter_str_per_configuration,
217 	restarter_str_refresh,
218 	restarter_str_restart_request,
219 	restarter_str_restarting_too_quickly,
220 	restarter_str_service_request,
221 	restarter_str_startd_restart
222 } restarter_str_t;
223 
224 struct restarter_state_transition_reason {
225 	restarter_str_t	str_key;
226 	const char	*str_short;
227 	const char	*str_long;
228 };
229 
230 /*
231  * Functions for updating the repository.
232  */
233 
234 /*
235  * When setting state to "maintenance", callers of restarter_set_states() can
236  * set aux_state to "service_request" to communicate that another service has
237  * requested maintenance state for the target service.
238  *
239  * Callers should use restarter_inst_validate_aux_fmri() to validate the fmri
240  * of the requested service and pass "service_request" for aux_state when
241  * calling restarter_set_states(). See inetd and startd for examples.
242  */
243 int restarter_set_states(restarter_event_handle_t *, const char *,
244     restarter_instance_state_t, restarter_instance_state_t,
245     restarter_instance_state_t, restarter_instance_state_t, restarter_error_t,
246     restarter_str_t);
247 int restarter_event_publish_retry(evchan_t *, const char *, const char *,
248     const char *, const char *, nvlist_t *, uint32_t);
249 
250 /*
251  * functions for retrieving the state transition reason messages
252  */
253 
254 #define	RESTARTER_STRING_VERSION	1
255 
256 uint32_t restarter_str_version(void);
257 const char *restarter_get_str_short(restarter_str_t);
258 const char *restarter_get_str_long(restarter_str_t);
259 
260 int restarter_store_contract(scf_instance_t *, ctid_t,
261     restarter_contract_type_t);
262 int restarter_remove_contract(scf_instance_t *, ctid_t,
263     restarter_contract_type_t);
264 
265 ssize_t restarter_state_to_string(restarter_instance_state_t, char *, size_t);
266 restarter_instance_state_t restarter_string_to_state(char *);
267 
268 #define	RESTARTER_METHOD_CONTEXT_VERSION	7
269 
270 struct method_context {
271 	/* Stable */
272 	uid_t		uid, euid;
273 	gid_t		gid, egid;
274 	int		ngroups;		/* -1 means use initgroups(). */
275 	gid_t		groups[NGROUPS_MAX];
276 	priv_set_t	*lpriv_set, *priv_set;
277 	char		*corefile_pattern;	/* Optional. */
278 	char		*project;		/* NULL for no change */
279 	char		*resource_pool;		/* NULL for project default */
280 	char		*working_dir;		/* NULL for :default */
281 	char		**env;			/* NULL for no env */
282 	size_t		env_sz;			/* size of env array */
283 
284 	/* Private */
285 	char		*vbuf;
286 	ssize_t		vbuf_sz;
287 	struct passwd	pwd;
288 	char		*pwbuf;
289 	ssize_t		pwbufsz;
290 };
291 
292 /*
293  * An error structure that contains a message string, and a type
294  * that can be used to determine course of action by the reciever
295  * of the error structure.
296  *
297  * type - usually will be an errno equivalent but could contain
298  * 	defined error types for exampe SCF_ERROR_XXX
299  * msg - must be at the end of the structure as if the message is
300  * 	longer than EMSGSIZE we will reallocate the structure to
301  * 	handle the overflow
302  */
303 typedef struct mc_error {
304 	int	destroy;	/* Flag to indicate destruction steps */
305 	int	type;		/* Type of error for decision making */
306 	int	size;		/* The size of the error message string */
307 	char 	msg[RESTARTER_ERRMSGSZ];
308 } mc_error_t;
309 
310 int restarter_rm_libs_loadable(void);
311 /* instance, restarter name, method name, command line, structure pointer */
312 mc_error_t *restarter_get_method_context(uint_t, scf_instance_t *,
313     scf_snapshot_t *, const char *, const char *, struct method_context **);
314 void restarter_mc_error_destroy(mc_error_t *);
315 int restarter_set_method_context(struct method_context *, const char **);
316 void restarter_free_method_context(struct method_context *);
317 
318 
319 int restarter_is_null_method(const char *);
320 int restarter_is_kill_method(const char *);
321 int restarter_is_kill_proc_method(const char *);
322 
323 /* Validate the inst fmri specified in  restarter_actions/auxiliary_fmri */
324 int restarter_inst_validate_ractions_aux_fmri(scf_instance_t *);
325 
326 /* Delete instance's restarter_actions/auxiliary_fmri property */
327 int restarter_inst_reset_ractions_aux_fmri(scf_instance_t *);
328 
329 /* Get boolean value from instance's restarter_actions/auxiliary_tty */
330 int restarter_inst_ractions_from_tty(scf_instance_t *);
331 
332 /* Delete instance's restarter/auxiliary_fmri property */
333 int restarter_inst_reset_aux_fmri(scf_instance_t *);
334 
335 /*
336  * Set instance's restarter/auxiliary_fmri, value come from
337  * restarter_actions/auxliary_fmri
338  */
339 int restarter_inst_set_aux_fmri(scf_instance_t *);
340 
341 #ifdef	__cplusplus
342 }
343 #endif
344 
345 #endif	/* _LIBRESTART_H */
346