xref: /freebsd/contrib/unbound/daemon/worker.h (revision be771a7b7f4580a30d99e41a5bb1b93a385a119d)
1 /*
2  * daemon/worker.h - worker that handles a pending list of requests.
3  *
4  * Copyright (c) 2007, NLnet Labs. All rights reserved.
5  *
6  * This software is open source.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * Redistributions of source code must retain the above copyright notice,
13  * this list of conditions and the following disclaimer.
14  *
15  * Redistributions in binary form must reproduce the above copyright notice,
16  * this list of conditions and the following disclaimer in the documentation
17  * and/or other materials provided with the distribution.
18  *
19  * Neither the name of the NLNET LABS nor the names of its contributors may
20  * be used to endorse or promote products derived from this software without
21  * specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file describes the worker structure that holds a list of
40  * pending requests and handles them.
41  */
42 
43 #ifndef DAEMON_WORKER_H
44 #define DAEMON_WORKER_H
45 
46 #include "libunbound/worker.h"
47 #include "util/netevent.h"
48 #include "util/locks.h"
49 #include "util/alloc.h"
50 #include "util/data/msgreply.h"
51 #include "util/data/msgparse.h"
52 #include "daemon/stats.h"
53 #include "util/module.h"
54 #include "dnstap/dnstap.h"
55 struct listen_dnsport;
56 struct outside_network;
57 struct config_file;
58 struct daemon;
59 struct listen_port;
60 struct ub_randstate;
61 struct regional;
62 struct tube;
63 struct daemon_remote;
64 struct query_info;
65 
66 /** worker commands */
67 enum worker_commands {
68 	/** make the worker quit */
69 	worker_cmd_quit,
70 	/** obtain statistics */
71 	worker_cmd_stats,
72 	/** obtain statistics without statsclear */
73 	worker_cmd_stats_noreset,
74 	/** execute remote control command */
75 	worker_cmd_remote,
76 	/** for fast-reload, perform stop */
77 	worker_cmd_reload_stop,
78 	/** for fast-reload, start again */
79 	worker_cmd_reload_start,
80 	/** for fast-reload, poll to make sure worker has released data */
81 	worker_cmd_reload_poll
82 };
83 
84 /**
85  * Structure holding working information for unbound.
86  * Holds globally visible information.
87  */
88 struct worker {
89 	/** the thread number (in daemon array). First in struct for debug. */
90 	int thread_num;
91 	/** global shared daemon structure */
92 	struct daemon* daemon;
93 	/** thread id */
94 	ub_thread_type thr_id;
95 #ifdef HAVE_GETTID
96 	/** thread tid, the LWP id. */
97 	pid_t thread_tid;
98 #endif
99 	/** pipe, for commands for this worker */
100 	struct tube* cmd;
101 	/** the event base this worker works with */
102 	struct comm_base* base;
103 	/** the frontside listening interface where request events come in */
104 	struct listen_dnsport* front;
105 	/** the backside outside network interface to the auth servers */
106 	struct outside_network* back;
107 	/** ports to be used by this worker. */
108 	int* ports;
109 	/** number of ports for this worker */
110 	int numports;
111 	/** the signal handler */
112 	struct comm_signal* comsig;
113 	/** commpoint to listen to commands. */
114 	struct comm_point* cmd_com;
115 	/** timer for statistics */
116 	struct comm_timer* stat_timer;
117 	/** ratelimit for errors, time value */
118 	time_t err_limit_time;
119 	/** ratelimit for errors, packet count */
120 	unsigned int err_limit_count;
121 
122 	/** random() table for this worker. */
123 	struct ub_randstate* rndstate;
124 	/** do we need to restart or quit (on signal) */
125 	int need_to_exit;
126 	/** allocation cache for this thread */
127 	struct alloc_cache *alloc;
128 	/** per thread statistics */
129 	struct ub_server_stats stats;
130 	/** thread scratch regional */
131 	struct regional* scratchpad;
132 
133 	/** module environment passed to modules, changed for this thread */
134 	struct module_env env;
135 
136 #ifdef USE_DNSTAP
137 	/** dnstap environment, changed for this thread */
138 	struct dt_env dtenv;
139 #endif
140 	/** reuse existing cache on reload if other conditions allow it. */
141 	int reuse_cache;
142 };
143 
144 /**
145  * Create the worker structure. Bare bones version, zeroed struct,
146  * with backpointers only. Use worker_init on it later.
147  * @param daemon: the daemon that this worker thread is part of.
148  * @param id: the thread number from 0.. numthreads-1.
149  * @param ports: the ports it is allowed to use, array.
150  * @param n: the number of ports.
151  * @return: the new worker or NULL on alloc failure.
152  */
153 struct worker* worker_create(struct daemon* daemon, int id, int* ports, int n);
154 
155 /**
156  * Initialize worker.
157  * Allocates event base, listens to ports
158  * @param worker: worker to initialize, created with worker_create.
159  * @param cfg: configuration settings.
160  * @param ports: list of shared query ports.
161  * @param do_sigs: if true, worker installs signal handlers.
162  * @return: false on error.
163  */
164 int worker_init(struct worker* worker, struct config_file *cfg,
165 	struct listen_port* ports, int do_sigs);
166 
167 /**
168  * Make worker work.
169  */
170 void worker_work(struct worker* worker);
171 
172 /**
173  * Delete worker.
174  */
175 void worker_delete(struct worker* worker);
176 
177 /**
178  * Send a command to a worker. Uses blocking writes.
179  * @param worker: worker to send command to.
180  * @param cmd: command to send.
181  */
182 void worker_send_cmd(struct worker* worker, enum worker_commands cmd);
183 
184 /**
185  * Init worker stats - includes server_stats_init, outside network and mesh.
186  * @param worker: the worker to init
187  */
188 void worker_stats_clear(struct worker* worker);
189 
190 #endif /* DAEMON_WORKER_H */
191