OpenDNSSEC-enforcer  1.3.14
daemon.c
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1 /*
2  * $Id: daemon.c 6482 2012-07-16 06:46:13Z jerry $
3  *
4  * Copyright (c) 2008-2009 Nominet UK. All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  * notice, this list of conditions and the following disclaimer in the
13  * documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
19  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
21  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
23  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
25  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  */
28 
29 /*
30  * daemon.c code needed to get a daemon up and running
31  *
32  * edit the DAEMONCONFIG and cmlParse function
33  * in daemon_util.[c|h] to add options specific
34  * to your app
35  *
36  * gcc -o daemon daemon_util.c daemon.c
37  *
38  * Most of this is based on stuff I have seen in NSD
39  */
40 
41 #include "config.h"
42 
43 #include <sys/types.h>
44 #include <sys/param.h>
45 #include <syslog.h>
46 #include <stdarg.h>
47 #include <errno.h>
48 #include <unistd.h>
49 #include <fcntl.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <signal.h>
53 
54 #include "daemon.h"
55 #include "daemon_util.h"
56 #include "privdrop.h"
57 
58 #include "ksm/ksm.h"
59 #include "ksm/dbsmsg.h"
60 #include "ksm/dbsdef.h"
61 #include "ksm/kmemsg.h"
62 #include "ksm/kmedef.h"
63 #include "ksm/message.h"
64 #include "ksm/string_util.h"
65 
66 #ifndef MAXPATHLEN
67 # define MAXPATHLEN 4096
68 #endif
69 
70 extern int server_init(DAEMONCONFIG *config);
71 extern void server_main(DAEMONCONFIG *config);
72 
74 
75 void
76 sig_handler (int sig)
77 {
78  switch (sig) {
79  case SIGCHLD:
80  return;
81  case SIGHUP:
82  return;
83  case SIGALRM:
84  break;
85  case SIGILL:
86  break;
87  case SIGUSR1:
88  break;
89  case SIGINT:
90  config.term = 2;
91  break;
92  case SIGTERM:
93  config.term = 1;
94  break;
95  default:
96  break;
97  }
98 }
99 
101 
102 void
104 {
105  /* Only unlink pidfile if its our pidfile */
106  if (daemon_our_pidfile) {
107  unlink(config.pidfile);
108  }
109 }
110 
111 int
112 main(int argc, char *argv[]){
113  int fd;
114  struct sigaction action;
115  const char* program; /* Temporary for program name */
116 
117  config.debug = false;
118  config.once = false;
119 
120  config.pidfile = NULL;
121  config.program = NULL;
122  config.host = NULL;
123  config.port = NULL;
124  config.user = (unsigned char *)calloc(MAX_USER_LENGTH, sizeof(char));
125  config.password = (unsigned char *)calloc(MAX_PASSWORD_LENGTH, sizeof(char));
126  config.schema = (unsigned char *)calloc(MAX_SCHEMA_LENGTH, sizeof(char));
127  config.DSSubmitCmd = (char *)calloc(MAXPATHLEN + 1024, sizeof(char));
128 
129  if (config.user == NULL || config.password == NULL || config.schema == NULL) {
130  log_msg(&config, LOG_ERR, "Malloc for config struct failed");
131  exit(1);
132  }
133  config.term = 0;
134 
135  /* Lets set up the logging first */
136  /* The program name is the last component of the program file name */
137  if ((program = strrchr(argv[0], '/'))) { /* EQUALS */
138  ++program; /* Point to character after last "/" */
139  }
140  else {
141  program = argv[0]; /* No slash, so use string given */
142  }
143  config.program = program;
145 
146  log_init(config.log_user, config.program);
147 
148  /* useful message */
149  log_msg(&config, LOG_INFO, "%s starting...", PACKAGE_NAME);
150 
151 #ifdef ENFORCER_TIMESHIFT
152  if (getenv("ENFORCER_TIMESHIFT")) {
153  log_msg(&config, LOG_INFO, "Timeshift mode detected, running once only!");
154  fprintf(stderr, "WARNING: Timeshift mode detected, running once only!\n");
155  config.once = true;
156  config.debug = true;
157  }
158 #endif /* ENFORCER_TIMESHIFT */
159 
160  /* Process command line */
161  cmdlParse(&config, &argc, argv);
162  if(config.debug) log_msg(&config, LOG_INFO, "%s DEBUG ON.", PACKAGE_NAME);
163 
164  /* If we dont debug then fork */
165  if(!config.debug){
166  /* Fork */
167  switch ((config.pid = fork())) {
168  case 0:
169  break;
170  case -1:
171  log_msg(&config, LOG_ERR, "fork failed: %s", strerror(errno));
172  unlink(config.pidfile);
173  exit(1);
174  default:
175  fprintf(stdout, "OpenDNSSEC ods-enforcerd started (version %s), pid %d\n", PACKAGE_VERSION, (int) config.pid);
176  log_msg(&config, LOG_INFO, "%s Parent exiting...", PACKAGE_NAME);
177  exit(0);
178  }
179 
180  /* Detach ourselves... */
181  if (setsid() == -1) {
182  log_msg(&config, LOG_ERR, "setsid() failed: %s", strerror(errno));
183  exit(1);
184  }
185 
186  if ((fd = open("/dev/null", O_RDWR, 0)) != -1) {
187  (void)dup2(fd, STDIN_FILENO);
188  (void)dup2(fd, STDOUT_FILENO);
189  (void)dup2(fd, STDERR_FILENO);
190  if (fd > 2)
191  (void)close(fd);
192  }
193  log_msg(&config, LOG_INFO, "%s forked OK...", PACKAGE_NAME);
194  } else {
195  log_msg(&config, LOG_INFO, "%s in debug mode - not forking...", PACKAGE_NAME);
196  }
197 
198  action.sa_handler = sig_handler;
199  sigfillset(&action.sa_mask);
200  action.sa_flags = 0;
201  sigaction(SIGTERM, &action, NULL);
202  sigaction(SIGHUP, &action, NULL);
203  sigaction(SIGINT, &action, NULL);
204  sigaction(SIGILL, &action, NULL);
205  sigaction(SIGUSR1, &action, NULL);
206  sigaction(SIGALRM, &action, NULL);
207  sigaction(SIGCHLD, &action, NULL);
208  action.sa_handler = SIG_IGN;
209  sigaction(SIGPIPE, &action, NULL);
210 
211  /* Get perms that we will be dropping to */
212  if (getPermsForDrop(&config) != 0) {
213  exit(1);
214  }
215 
216  /* Run the server specific code. You need to provide this function somewhere
217  this sets our pidfile */
218  if (server_init(&config) != 0) {
219  exit(1);
220  }
221 
222  /* make the directory for the pidfile if required; do this before we drop
223  privs */
224  if (createPidDir(&config) != 0) {
225  exit(1);
226  }
227 
228  /*
229  * Drop permissions.
230  * This function exits if something goes wrong
231  */
232  privdrop(config.username, config.groupname, NULL);
233 
234  config.uid = geteuid();
235  config.gid = getegid();
236  config.pid = getpid();
237 
238  atexit(exit_function);
239 
240  log_msg(&config, LOG_NOTICE, "%s started (version %s), pid %d", PACKAGE_NAME, PACKAGE_VERSION,
241  (int) config.pid);
242 
243  MsgInit();
246 
247  /* Do something. You need to provide this function somewhere */
248  server_main(&config);
249 
250  /* Free stuff here (exit from sigs pass through) */
251  MsgRundown();
252  if (config.host) free(config.host);
253  if (config.port) free(config.port);
254  free(config.user);
255  free(config.password);
256  free(config.schema);
257  free(config.DSSubmitCmd);
258 
259  StrFree(config.username);
260  StrFree(config.groupname);
261 #if 0
262  StrFree(config.chrootdir);
263 #endif
264 
265  exit(0);
266 
267 }
268