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