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