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