OpenDNSSEC-enforcer  1.4.6
daemon.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2008-2009 Nominet UK. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  * notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  * notice, this list of conditions and the following disclaimer in the
11  * documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
17  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
19  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
21  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
22  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
23  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  */
26 
27 /*
28  * daemon.c code needed to get a daemon up and running
29  *
30  * edit the DAEMONCONFIG and cmlParse function
31  * in daemon_util.[c|h] to add options specific
32  * to your app
33  *
34  * gcc -o daemon daemon_util.c daemon.c
35  *
36  * Most of this is based on stuff I have seen in NSD
37  */
38 
39 #include "config.h"
40 
41 #include <sys/types.h>
42 #include <sys/param.h>
43 #include <syslog.h>
44 #include <stdarg.h>
45 #include <errno.h>
46 #include <unistd.h>
47 #include <fcntl.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <signal.h>
51 
52 #include "daemon.h"
53 #include "daemon_util.h"
54 #include "privdrop.h"
55 
56 #include "ksm/ksm.h"
57 #include "ksm/dbsmsg.h"
58 #include "ksm/dbsdef.h"
59 #include "ksm/kmemsg.h"
60 #include "ksm/kmedef.h"
61 #include "ksm/message.h"
62 #include "ksm/string_util.h"
63 
64 #ifndef MAXPATHLEN
65 # define MAXPATHLEN 4096
66 #endif
67 
68 extern int server_init(DAEMONCONFIG *config);
69 extern void server_main(DAEMONCONFIG *config);
70 
72 
73 void
74 sig_handler (int sig)
75 {
76  switch (sig) {
77  case SIGCHLD:
78  return;
79  case SIGHUP:
80  return;
81  case SIGALRM:
82  break;
83  case SIGILL:
84  break;
85  case SIGUSR1:
86  break;
87  case SIGINT:
88  config.term = 2;
89  break;
90  case SIGTERM:
91  config.term = 1;
92  break;
93  default:
94  break;
95  }
96 }
97 
99 
100 void
102 {
103  /* Only unlink pidfile if its our pidfile */
104  if (daemon_our_pidfile) {
105  unlink(config.pidfile);
106  }
107 }
108 
109 int
110 main(int argc, char *argv[]){
111  int fd;
112  struct sigaction action;
113  const char* program; /* Temporary for program name */
114 
115  config.debug = false;
116  config.once = false;
117 
118  config.pidfile = NULL;
119  config.pidfile_set = 0;
120  config.program = NULL;
121  config.host = NULL;
122  config.port = NULL;
123  config.user = (unsigned char *)calloc(MAX_USER_LENGTH, sizeof(char));
124  config.password = (unsigned char *)calloc(MAX_PASSWORD_LENGTH, sizeof(char));
125  config.schema = (unsigned char *)calloc(MAX_SCHEMA_LENGTH, sizeof(char));
126  config.DSSubmitCmd = (char *)calloc(MAXPATHLEN + 1024, sizeof(char));
127  config.policy = NULL;
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  if (config.pidfile && !config.pidfile_set) free(config.pidfile);
255  free(config.user);
256  free(config.password);
257  free(config.schema);
258  free(config.DSSubmitCmd);
259 
260  StrFree(config.username);
261  StrFree(config.groupname);
262 #if 0
263  StrFree(config.chrootdir);
264 #endif
265 
266  exit(0);
267 
268 }
269 
void server_main(DAEMONCONFIG *config)
Definition: enforcer.c:81
unsigned char * password
Definition: daemon.h:106
int main(int argc, char *argv[])
Definition: daemon.c:110
unsigned char * schema
Definition: daemon.h:107
void exit_function(void)
Definition: daemon.c:101
bool once
Definition: daemon.h:89
#define DEFAULT_LOG_FACILITY
Definition: daemon.h:79
#define MAXPATHLEN
Definition: daemon.c:65
pid_t pid
Definition: daemon.h:90
#define StrFree(x)
Definition: string_util.h:66
void sig_handler(int sig)
Definition: daemon.c:74
char * pidfile
Definition: daemon.h:91
char * DSSubmitCmd
Definition: daemon.h:114
int privdrop(const char *username, const char *groupname, const char *newroot)
Definition: privdrop.c:48
int daemon_our_pidfile
Definition: daemon.c:98
int log_user
Definition: daemon.h:118
const char * program
Definition: daemon.h:87
char * username
Definition: daemon.h:94
int getPermsForDrop(DAEMONCONFIG *config)
Definition: daemon_util.c:91
uid_t uid
Definition: daemon.h:92
#define MAX_USER_LENGTH
Definition: daemon.h:67
#define DBS_MIN_VALUE
Definition: dbsmsg.h:6
void cmdlParse(DAEMONCONFIG *config, int *argc, char **argv)
Definition: daemon_util.c:623
void log_init(int facility, const char *program_name)
Definition: daemon_util.c:265
#define MAX_PASSWORD_LENGTH
Definition: daemon.h:69
unsigned char * host
Definition: daemon.h:105
int pidfile_set
Definition: daemon.h:119
void MsgRegister(int min, int max, const char **message, MSG_OUTPUT_FUNCTION output)
Definition: message.c:141
int term
Definition: daemon.h:100
#define KME_MAX_VALUE
Definition: kmemsg.h:7
#define DBS_MAX_VALUE
Definition: dbsmsg.h:7
void ksm_log_msg(const char *format)
Definition: daemon_util.c:313
bool debug
Definition: daemon.h:88
void MsgRundown(void)
Definition: message.c:412
int createPidDir(DAEMONCONFIG *config)
Definition: daemon_util.c:536
#define KME_MIN_VALUE
Definition: kmemsg.h:6
#define MAX_SCHEMA_LENGTH
Definition: daemon.h:70
char * policy
Definition: daemon.h:116
gid_t gid
Definition: daemon.h:93
DAEMONCONFIG config
Definition: daemon.c:71
char * groupname
Definition: daemon.h:95
void log_msg(DAEMONCONFIG *config, int priority, const char *format,...)
Definition: daemon_util.c:294
unsigned char * port
Definition: daemon.h:108
void MsgInit(void)
Definition: message.c:63
int server_init(DAEMONCONFIG *config)
Definition: enforcer.c:62
unsigned char * user
Definition: daemon.h:104