mdw@git.distorted.org.uk Git - secnet/blob - secnet.c

   1 /* $Log: secnet.c,v $
   2  * Revision 1.1  1996/03/13 22:27:41  sde1000
   3  * Initial revision
   4  *
   5  */
   6
   7 extern char version[];
   8
   9 #include "secnet.h"
  10 #include <stdio.h>
  11 #include <string.h>
  12 #include <getopt.h>
  13 #include <errno.h>
  14 #include <unistd.h>
  15 #include <sys/socket.h>
  16 #include <arpa/inet.h>
  17 #include <pwd.h>
  18
  19 #include "util.h"
  20 #include "conffile.h"
  21 #include "process.h"
  22
  23 /* XXX should be from autoconf */
  24 static char *configfile="/etc/secnet/secnet.conf";
  25 static char *sites_key="sites";
  26 bool_t just_check_config=False;
  27 static char *userid=NULL;
  28 static uid_t uid=0;
  29 bool_t background=True;
  30 static char *pidfile=NULL;
  31 bool_t require_root_privileges=False;
  32 string_t require_root_privileges_explanation=NULL;
  33
  34 static pid_t secnet_pid;
  35
  36 /* from log.c */
  37 extern uint32_t message_level;
  38 extern bool_t secnet_is_daemon;
  39 extern struct log_if *system_log;
  40
  41 /* from process.c */
  42 extern void start_signal_handling(void);
  43
  44 /* Structures dealing with poll() call */
  45 struct poll_interest {
  46     beforepoll_fn *before;
  47     afterpoll_fn *after;
  48     void *state;
  49     uint32_t max_nfds;
  50     uint32_t nfds;
  51     string_t desc;
  52     struct poll_interest *next;
  53 };
  54 static struct poll_interest *reg=NULL;
  55 static uint32_t total_nfds=10;
  56
  57 static bool_t finished=False;
  58
  59 /* Parse the command line options */
  60 static void parse_options(int argc, char **argv)
  61 {
  62     int c;
  63
  64     while (True) {
  65         int option_index = 0;
  66         static struct option long_options[] = {
  67             {"verbose", 0, 0, 'v'},
  68             {"nowarnings", 0, 0, 'w'},
  69             {"help", 0, 0, 2},
  70             {"version", 0, 0, 1},
  71             {"nodetach", 0, 0, 'n'},
  72             {"silent", 0, 0, 'f'},
  73             {"quiet", 0, 0, 'f'},
  74             {"debug", 1, 0, 'd'},
  75             {"config", 1, 0, 'c'},
  76             {"just-check-config", 0, 0, 'j'},
  77             {"sites-key", 1, 0, 's'},
  78             {0,0,0,0}
  79         };
  80
  81         c=getopt_long(argc, argv, "vwdnjc:ft:s:",
  82                       long_options, &option_index);
  83         if (c==-1)
  84             break;
  85
  86         switch(c) {
  87         case 2:
  88             /* Help */
  89             fprintf(stderr,
  90                     "Usage: secnet [OPTION]...\n\n"
  91                     "  -f, --silent, --quiet   suppress error messages\n"
  92                     "  -w, --nowarnings        suppress warnings\n"
  93                     "  -v, --verbose           output extra diagnostics\n"
  94                     "  -c, --config=filename   specify a configuration file\n"
  95                     "  -j, --just-check-config stop after reading "
  96                     "configuration file\n"
  97                     "  -s, --sites-key=name    configuration key that "
  98                     "specifies active sites\n"
  99                     "  -n, --nodetach          do not run in background\n"
 100                     "  -d, --debug=item,...    set debug options\n"
 101                     "      --help              display this help and exit\n"
 102                     "      --version           output version information "
 103                     "and exit\n"
 104                 );
 105             exit(0);
 106             break;
 107
 108         case 1:
 109             /* Version */
 110             fprintf(stderr,"%s\n",version);
 111             exit(0);
 112             break;
 113
 114         case 'v':
 115             message_level|=M_INFO|M_NOTICE|M_WARNING|M_ERR|M_SECURITY|
 116                 M_FATAL;
 117             break;
 118
 119         case 'w':
 120             message_level&=(~M_WARNING);
 121             break;
 122
 123         case 'd':
 124             message_level|=M_DEBUG_CONFIG|M_DEBUG_PHASE|M_DEBUG;
 125             break;
 126
 127         case 'f':
 128             message_level=M_FATAL;
 129             break;
 130
 131         case 'n':
 132             background=False;
 133             break;
 134
 135         case 'c':
 136             if (optarg)
 137                 configfile=safe_strdup(optarg,"config_filename");
 138             else
 139                 fatal("secnet: no config filename specified");
 140             break;
 141
 142         case 'j':
 143             just_check_config=True;
 144             break;
 145
 146         case 's':
 147             if (optarg)
 148                 sites_key=safe_strdup(optarg,"sites-key");
 149             else
 150                 fatal("secnet: no sites key specified");
 151             break;
 152
 153         case '?':
 154             break;
 155
 156         default:
 157             Message(M_ERR,"secnet: Unknown getopt code %c\n",c);
 158         }
 159     }
 160
 161     if (argc-optind != 0) {
 162         Message(M_ERR,"secnet: You gave extra command line parameters, "
 163                 "which were ignored.\n");
 164     }
 165 }
 166
 167 static void setup(dict_t *config)
 168 {
 169     list_t *l;
 170     item_t *site;
 171     dict_t *system;
 172     struct passwd *pw;
 173     struct cloc loc;
 174     int i;
 175
 176     l=dict_lookup(config,"system");
 177
 178     if (!l || list_elem(l,0)->type!=t_dict) {
 179         fatal("configuration does not include a \"system\" dictionary\n");
 180     }
 181     system=list_elem(l,0)->data.dict;
 182     loc=list_elem(l,0)->loc;
 183
 184     /* Arrange systemwide log facility */
 185     l=dict_lookup(system,"log");
 186     if (!l) {
 187         fatal("configuration does not include a system/log facility\n");
 188     }
 189     system_log=init_log(l);
 190
 191     /* Who are we supposed to run as? */
 192     userid=dict_read_string(system,"userid",False,"system",loc);
 193     if (userid) {
 194         do {
 195             pw=getpwent();
 196             if (pw && strcmp(pw->pw_name,userid)==0) {
 197                 uid=pw->pw_uid;
 198                 break;
 199             }
 200         } while(pw);
 201         endpwent();
 202         if (uid==0) {
 203             fatal("userid \"%s\" not found\n",userid);
 204         }
 205     }
 206
 207     /* Pidfile name */
 208     pidfile=dict_read_string(system,"pidfile",False,"system",loc);
 209
 210     /* Check whether we need root privileges */
 211     if (require_root_privileges && uid!=0) {
 212         fatal("the following configured feature (\"%s\") requires "
 213               "that secnet retain root privileges while running.\n",
 214               require_root_privileges_explanation);
 215     }
 216
 217     /* Go along site list, starting sites */
 218     l=dict_lookup(config,sites_key);
 219     if (!l) {
 220         Message(M_WARNING,"secnet: configuration key \"%s\" is missing; no "
 221                 "remote sites are defined\n",sites_key);
 222     } else {
 223         i=0;
 224         while ((site=list_elem(l, i++))) {
 225             struct site_if *s;
 226             if (site->type!=t_closure) {
 227                 cfgfatal(site->loc,"system","non-closure in site list");
 228             }
 229             if (site->data.closure->type!=CL_SITE) {
 230                 cfgfatal(site->loc,"system","non-site closure in site list");
 231             }
 232             s=site->data.closure->interface;
 233             s->control(s->st,True);
 234         }
 235     }
 236 }
 237
 238 void register_for_poll(void *st, beforepoll_fn *before,
 239                        afterpoll_fn *after, uint32_t max_nfds, string_t desc)
 240 {
 241     struct poll_interest *i;
 242
 243     i=safe_malloc(sizeof(*i),"register_for_poll");
 244     i->before=before;
 245     i->after=after;
 246     i->state=st;
 247     i->max_nfds=max_nfds;
 248     i->nfds=0;
 249     i->desc=desc;
 250     total_nfds+=max_nfds;
 251     i->next=reg;
 252     reg=i;
 253     return;
 254 }
 255
 256 static void system_phase_hook(void *sst, uint32_t newphase)
 257 {
 258     if (newphase==PHASE_SHUTDOWN && pidfile) {
 259         /* Try to unlink the pidfile; don't care if it fails */
 260         unlink(pidfile);
 261     }
 262 }
 263
 264 static void run(void)
 265 {
 266     struct timeval tv_now;
 267     uint64_t now;
 268     struct poll_interest *i;
 269     int rv, nfds, remain, idx;
 270     int timeout;
 271     struct pollfd *fds;
 272
 273     fds=alloca(sizeof(*fds)*total_nfds);
 274     if (!fds) {
 275         fatal("run: couldn't alloca\n");
 276     }
 277
 278     Message(M_NOTICE,"%s [%d]: starting\n",version,secnet_pid);
 279
 280     do {
 281         if (gettimeofday(&tv_now, NULL)!=0) {
 282             fatal_perror("main loop: gettimeofday");
 283         }
 284         now=((uint64_t)tv_now.tv_sec*(uint64_t)1000)+
 285             ((uint64_t)tv_now.tv_usec/(uint64_t)1000);
 286         idx=0;
 287         for (i=reg; i; i=i->next) {
 288             i->after(i->state, fds+idx, i->nfds, &tv_now, &now);
 289             idx+=i->nfds;
 290         }
 291         remain=total_nfds;
 292         idx=0;
 293         timeout=-1;
 294         for (i=reg; i; i=i->next) {
 295             nfds=remain;
 296             rv=i->before(i->state, fds+idx, &nfds, &timeout, &tv_now, &now);
 297             if (rv!=0) {
 298                 /* XXX we need to handle this properly: increase the
 299                    nfds available */
 300                 fatal("run: beforepoll_fn (%s) returns %d\n",i->desc,rv);
 301             }
 302             if (timeout<-1) {
 303                 fatal("run: beforepoll_fn (%s) set timeout to %d\n",timeout);
 304             }
 305             idx+=nfds;
 306             remain-=nfds;
 307             i->nfds=nfds;
 308         }
 309         do {
 310             if (finished) break;
 311             rv=poll(fds, idx, timeout);
 312             if (rv<0) {
 313                 if (errno!=EINTR) {
 314                     fatal_perror("run: poll");
 315                 }
 316             }
 317         } while (rv<0);
 318     } while (!finished);
 319 }
 320
 321 static void droppriv(void)
 322 {
 323     FILE *pf=NULL;
 324     pid_t p;
 325
 326     add_hook(PHASE_SHUTDOWN,system_phase_hook,NULL);
 327
 328     /* Open the pidfile for writing now: we may be unable to do so
 329        once we drop privileges. */
 330     if (pidfile) {
 331         pf=fopen(pidfile,"w");
 332         if (!pf) {
 333             fatal_perror("cannot open pidfile \"%s\"",pidfile);
 334         }
 335     }
 336     if (!background && pf) {
 337         fprintf(pf,"%d\n",getpid());
 338         fclose(pf);
 339     }
 340
 341     /* Now drop privileges */
 342     if (uid!=0) {
 343         if (setuid(uid)!=0) {
 344             fatal_perror("can't set uid to \"%s\"",userid);
 345         }
 346     }
 347     if (background) {
 348         p=fork();
 349         if (p>0) {
 350             if (pf) {
 351                 /* Parent process - write pidfile, exit */
 352                 fprintf(pf,"%d\n",p);
 353                 fclose(pf);
 354             }
 355             exit(0);
 356         } else if (p==0) {
 357             /* Child process - all done, just carry on */
 358             if (pf) fclose(pf);
 359             /* Close stdin, stdout and stderr; we don't need them any more */
 360             close(0);
 361             close(1);
 362             close(2);
 363             secnet_is_daemon=True;
 364         } else {
 365             /* Error */
 366             fatal_perror("cannot fork");
 367             exit(1);
 368         }
 369     }
 370     secnet_pid=getpid();
 371 }
 372
 373 static signal_notify_fn finish,ignore_hup;
 374 static void finish(void *st, int signum)
 375 {
 376     finished=True;
 377     Message(M_NOTICE,"%s [%d]: received %s\n",version,secnet_pid,(string_t)st);
 378 }
 379 static void ignore_hup(void *st, int signum)
 380 {
 381     Message(M_INFO,"%s [%d]: received SIGHUP\n",version,secnet_pid);
 382     return;
 383 }
 384
 385 int main(int argc, char **argv)
 386 {
 387     dict_t *config;
 388
 389     enter_phase(PHASE_GETOPTS);
 390     parse_options(argc,argv);
 391
 392     enter_phase(PHASE_READCONFIG);
 393     config=read_conffile(configfile);
 394
 395     enter_phase(PHASE_SETUP);
 396     setup(config);
 397
 398     if (just_check_config) {
 399         Message(M_INFO,"configuration file check complete\n");
 400         exit(0);
 401     }
 402
 403     enter_phase(PHASE_GETRESOURCES);
 404     /* Appropriate phase hooks will have been run */
 405
 406     enter_phase(PHASE_DROPPRIV);
 407     droppriv();
 408
 409     start_signal_handling();
 410     request_signal_notification(SIGTERM,finish,"SIGTERM");
 411     if (!background) request_signal_notification(SIGINT,finish,"SIGINT");
 412     request_signal_notification(SIGHUP,ignore_hup,NULL);
 413     enter_phase(PHASE_RUN);
 414     run();
 415
 416     enter_phase(PHASE_SHUTDOWN);
 417     Message(M_NOTICE,"%s [%d]: finished\n",version,secnet_pid);
 418
 419     return 0;
 420 }