1 /* $NetBSD: daemon-bozo.c,v 1.22 2020/10/15 04:21:53 mrg Exp $ */
2
3 /* $eterna: daemon-bozo.c,v 1.24 2011/11/18 09:21:15 mrg Exp $ */
4
5 /*
6 * Copyright (c) 1997-2019 Matthew R. Green
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer and
16 * dedication in the documentation and/or other materials provided
17 * with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 */
32
33 /* this code implements daemon mode for bozohttpd */
34
35 #ifndef NO_DAEMON_MODE
36
37 #include <sys/param.h>
38 #include <sys/socket.h>
39 #include <sys/wait.h>
40
41 #include <netinet/in.h>
42
43 #include <assert.h>
44 #include <errno.h>
45 #include <netdb.h>
46 #include <poll.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <unistd.h>
51
52 #include "bozohttpd.h"
53
54 static void sigchild(int); /* SIGCHLD handler */
55
56 #ifndef POLLRDNORM
57 #define POLLRDNORM 0
58 #endif
59 #ifndef POLLRDBAND
60 #define POLLRDBAND 0
61 #endif
62 #ifndef INFTIM
63 #define INFTIM -1
64 #endif
65 #ifndef USE_ARG
66 #define USE_ARG(x) /*LINTED*/(void)&(x)
67 #endif
68
69 static const char* pidfile_path = NULL;
70 static pid_t pidfile_pid = 0;
71
72 static void
sigchild(int signo)73 sigchild(int signo)
74 {
75 USE_ARG(signo);
76 while (waitpid(-1, NULL, WNOHANG) > 0)
77 /* nothing */;
78 }
79
80 /* Signal handler to exit in a controlled manner. This ensures that
81 * any atexit(3) handlers are properly executed. */
82 BOZO_DEAD static void
controlled_exit(int signo)83 controlled_exit(int signo)
84 {
85 USE_ARG(signo);
86 exit(EXIT_SUCCESS);
87 }
88
89 static void
remove_pidfile(void)90 remove_pidfile(void)
91 {
92
93 if (pidfile_path != NULL && pidfile_pid == getpid()) {
94 (void)unlink(pidfile_path);
95 pidfile_path = NULL;
96 }
97 }
98
99 static void
create_pidfile(bozohttpd_t * httpd)100 create_pidfile(bozohttpd_t *httpd)
101 {
102 FILE *file;
103
104 assert(pidfile_path == NULL);
105
106 if (httpd->pidfile == NULL)
107 return;
108
109 if (atexit(remove_pidfile) == -1)
110 bozoerr(httpd, 1, "Failed to install pidfile handler");
111
112 if ((file = fopen(httpd->pidfile, "w")) == NULL)
113 bozoerr(httpd, 1, "Failed to create pidfile '%s'",
114 httpd->pidfile);
115 (void)fprintf(file, "%d\n", getpid());
116 (void)fclose(file);
117
118 pidfile_path = httpd->pidfile;
119 pidfile_pid = getpid();
120
121 debug((httpd, DEBUG_FAT, "Created pid file '%s' for pid %d",
122 pidfile_path, pidfile_pid));
123 }
124
125 void
bozo_daemon_init(bozohttpd_t * httpd)126 bozo_daemon_init(bozohttpd_t *httpd)
127 {
128 struct addrinfo h, *r, *r0;
129 const char *portnum;
130 int e, i, on = 1;
131
132 if (!httpd->background && !httpd->foreground)
133 return;
134
135 if (!httpd->background)
136 httpd->background = 1;
137
138 portnum = (httpd->bindport) ? httpd->bindport : "http";
139
140 memset(&h, 0, sizeof(h));
141 h.ai_family = PF_UNSPEC;
142 h.ai_socktype = SOCK_STREAM;
143 h.ai_flags = AI_PASSIVE;
144 e = getaddrinfo(httpd->bindaddress, portnum, &h, &r0);
145 if (e)
146 bozoerr(httpd, 1, "getaddrinfo([%s]:%s): %s",
147 httpd->bindaddress ? httpd->bindaddress : "*",
148 portnum, gai_strerror(e));
149 for (r = r0; r != NULL; r = r->ai_next)
150 httpd->nsock++;
151 httpd->sock = bozomalloc(httpd, httpd->nsock * sizeof(*httpd->sock));
152 httpd->fds = bozomalloc(httpd, httpd->nsock * sizeof(*httpd->fds));
153 for (i = 0, r = r0; r != NULL; r = r->ai_next) {
154 httpd->sock[i] = socket(r->ai_family, SOCK_STREAM, 0);
155 if (httpd->sock[i] == -1)
156 continue;
157 if (setsockopt(httpd->sock[i], SOL_SOCKET, SO_REUSEADDR, &on,
158 sizeof(on)) == -1)
159 bozowarn(httpd, "setsockopt SO_REUSEADDR: %s",
160 strerror(errno));
161 if (bind(httpd->sock[i], r->ai_addr, r->ai_addrlen) == -1)
162 continue;
163 if (listen(httpd->sock[i], SOMAXCONN) == -1)
164 continue;
165 httpd->fds[i].events = POLLIN | POLLPRI | POLLRDNORM |
166 POLLRDBAND | POLLERR;
167 httpd->fds[i].fd = httpd->sock[i];
168 i++;
169 }
170 if (i == 0)
171 bozoerr(httpd, 1, "could not find any addresses to bind");
172 httpd->nsock = i;
173 freeaddrinfo(r0);
174
175 if (httpd->foreground == 0)
176 daemon(1, 0);
177
178 create_pidfile(httpd);
179
180 bozowarn(httpd, "started in daemon mode as `%s' port `%s' root `%s'",
181 httpd->virthostname, portnum, httpd->slashdir);
182
183 signal(SIGHUP, controlled_exit);
184 signal(SIGINT, controlled_exit);
185 signal(SIGTERM, controlled_exit);
186
187 signal(SIGCHLD, sigchild);
188 }
189
190 void
bozo_daemon_closefds(bozohttpd_t * httpd)191 bozo_daemon_closefds(bozohttpd_t *httpd)
192 {
193 int i;
194
195 for (i = 0; i < httpd->nsock; i++)
196 close(httpd->sock[i]);
197 }
198
199 static void
daemon_runchild(bozohttpd_t * httpd,int fd)200 daemon_runchild(bozohttpd_t *httpd, int fd)
201 {
202 httpd->request_times++;
203
204 /* setup stdin/stdout/stderr */
205 dup2(fd, 0);
206 dup2(fd, 1);
207 /*dup2(fd, 2);*/
208 close(fd);
209 }
210
211 static int
daemon_poll_err(bozohttpd_t * httpd,int idx)212 daemon_poll_err(bozohttpd_t *httpd, int idx)
213 {
214 if ((httpd->fds[idx].revents & (POLLNVAL|POLLERR|POLLHUP)) == 0)
215 return 0;
216
217 bozowarn(httpd, "poll on fd %d pid %d revents %d: %s",
218 httpd->fds[idx].fd, getpid(), httpd->fds[idx].revents,
219 strerror(errno));
220 bozowarn(httpd, "nsock = %d", httpd->nsock);
221 close(httpd->sock[idx]);
222 httpd->nsock--;
223 bozowarn(httpd, "nsock now = %d", httpd->nsock);
224 /* no sockets left */
225 if (httpd->nsock == 0)
226 exit(0);
227 /* last socket closed is the easy case */
228 if (httpd->nsock != idx) {
229 memmove(&httpd->fds[idx], &httpd->fds[idx+1],
230 (httpd->nsock - idx) * sizeof(*httpd->fds));
231 memmove(&httpd->sock[idx], &httpd->sock[idx+1],
232 (httpd->nsock - idx) * sizeof(*httpd->sock));
233 }
234
235 return 1;
236 }
237
238 /*
239 * the parent never returns from this function, only children that
240 * are ready to run... XXXMRG - still true in fork-lesser bozo?
241 */
242 int
bozo_daemon_fork(bozohttpd_t * httpd)243 bozo_daemon_fork(bozohttpd_t *httpd)
244 {
245 int i;
246
247 debug((httpd, DEBUG_FAT, "%s: pid %u request_times %d",
248 __func__, getpid(),
249 httpd->request_times));
250 /* if we've handled 5 files, exit and let someone else work */
251 if (httpd->request_times > 5 ||
252 (httpd->background == 2 && httpd->request_times > 0))
253 _exit(0);
254
255 #if 1
256 if (httpd->request_times > 0)
257 _exit(0);
258 #endif
259
260 while (httpd->background) {
261 struct sockaddr_storage ss;
262 socklen_t slen;
263 int fd;
264
265 if (httpd->nsock == 0)
266 exit(0);
267
268 /*
269 * wait for a connection, then fork() and return NULL in
270 * the parent, who will come back here waiting for another
271 * connection. read the request in in the child, and return
272 * it, for processing.
273 */
274 again:
275 if (poll(httpd->fds, (unsigned)httpd->nsock, INFTIM) == -1) {
276 /* fail on programmer errors */
277 if (errno == EFAULT ||
278 errno == EINVAL)
279 bozoerr(httpd, 1, "poll: %s",
280 strerror(errno));
281
282 /* sleep on some temporary kernel failures */
283 if (errno == ENOMEM ||
284 errno == EAGAIN)
285 sleep(1);
286
287 goto again;
288 }
289
290 for (i = 0; i < httpd->nsock; i++) {
291 if (daemon_poll_err(httpd, i))
292 break;
293 if (httpd->fds[i].revents == 0)
294 continue;
295
296 slen = sizeof(ss);
297 fd = accept(httpd->fds[i].fd,
298 (struct sockaddr *)(void *)&ss, &slen);
299 if (fd == -1) {
300 if (errno == EFAULT ||
301 errno == EINVAL)
302 bozoerr(httpd, 1, "accept: %s",
303 strerror(errno));
304
305 if (errno == ENOMEM ||
306 errno == EAGAIN)
307 sleep(1);
308
309 continue;
310 }
311
312 #if 0
313 /*
314 * This code doesn't work. It interacts very poorly
315 * with ~user translation and needs to be fixed.
316 */
317 if (httpd->request_times > 0) {
318 daemon_runchild(httpd, fd);
319 return 0;
320 }
321 #endif
322
323 switch (fork()) {
324 case -1: /* eep, failure */
325 bozowarn(httpd, "fork() failed, sleeping for "
326 "10 seconds: %s", strerror(errno));
327 close(fd);
328 sleep(10);
329 break;
330
331 case 0: /* child */
332 daemon_runchild(httpd, fd);
333 return 0;
334
335 default: /* parent */
336 close(fd);
337 break;
338 }
339 }
340 }
341 return 0;
342 }
343
344 #endif /* NO_DAEMON_MODE */
345