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 static char *version="secnet version " VERSION " $Date: 1996/03/13 22:27:41 $";
   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 #include "modules.h"
  27
  28 /* Command-line options (possibly config-file options too) */
  29 static char *configfile="/etc/secnet/secnet.conf";
  30 static char *userid=NULL;
  31 static uid_t uid=0;
  32 static bool_t background=True;
  33 static char *pidfile=NULL;
  34
  35 /* Structures dealing with poll() call */
  36 struct poll_interest {
  37     beforepoll_fn *before;
  38     afterpoll_fn *after;
  39     void *state;
  40     uint32_t max_nfds;
  41     uint32_t nfds;
  42     string_t desc;
  43     struct poll_interest *next;
  44 };
  45 static struct poll_interest *reg=NULL;
  46 static uint32_t total_nfds=10;
  47
  48 static bool_t finished=False;
  49
  50 /* Parse the command line options */
  51 static void parse_options(int argc, char **argv)
  52 {
  53     int c;
  54
  55     while (True) {
  56         int option_index = 0;
  57         static struct option long_options[] = {
  58             {"verbose", 0, 0, 'v'},
  59             {"nowarnings", 0, 0, 'w'},
  60             {"help", 0, 0, 2},
  61             {"version", 0, 0, 1},
  62             {"nodetach", 0, 0, 'n'},
  63             {"silent", 0, 0, 'f'},
  64             {"quiet", 0, 0, 'f'},
  65             {"debug", 1, 0, 'd'},
  66             {"config", 1, 0, 'c'},
  67             {0,0,0,0}
  68         };
  69
  70         c=getopt_long(argc, argv, "vwdnc:ft:",
  71                       long_options, &option_index);
  72         if (c==-1)
  73             break;
  74
  75         switch(c) {
  76         case 2:
  77             /* Help */
  78             fprintf(stderr,
  79                     "Usage: secnet [OPTION]...\n\n"
  80                     "  -f, --silent, --quiet   suppress error messages\n"
  81                     "  -w, --nowarnings        suppress warnings\n"
  82                     "  -v, --verbose           output extra diagnostics\n"
  83                     "  -c, --config=filename   specify a configuration file\n"
  84                     "  -n, --nodetach          do not run in background\n"
  85                     "  -d, --debug=item,...    set debug options\n"
  86                     "      --help              display this help and exit\n"
  87                     "      --version           output version information and exit\n"
  88                 );
  89             exit(0);
  90             break;
  91
  92         case 1:
  93             /* Version */
  94             fprintf(stderr,"%s\n",version);
  95             exit(0);
  96             break;
  97
  98         case 'v':
  99             message_level|=M_INFO|M_WARNING|M_ERROR|M_FATAL;
 100             break;
 101
 102         case 'n':
 103             background=False;
 104             break;
 105
 106         case 'd':
 107             message_level|=M_DEBUG_CONFIG|M_DEBUG_PHASE;
 108             break;
 109
 110         case 'f':
 111             message_level=M_FATAL;
 112             break;
 113
 114         case 'c':
 115             if (optarg)
 116                 configfile=safe_strdup(optarg,"config_filename");
 117             else
 118                 fatal("secnet: no config filename specified");
 119             break;
 120
 121         case '?':
 122             break;
 123
 124         default:
 125             Message(M_WARNING,"secnet: Unknown getopt code %c\n",c);
 126         }
 127     }
 128
 129     if (argc-optind != 0) {
 130         Message(M_WARNING,"secnet: You gave extra command line parameters, "
 131                 "which were ignored.\n");
 132     }
 133 }
 134
 135 static void setup(dict_t *config)
 136 {
 137     list_t *l;
 138     item_t *site;
 139     dict_t *system;
 140     struct log_if *log;
 141     struct passwd *pw;
 142     struct cloc loc;
 143     int i;
 144
 145     l=dict_lookup(config,"system");
 146
 147     if (!l || list_elem(l,0)->type!=t_dict) {
 148         fatal("configuration does not include a \"system\" dictionary\n");
 149     }
 150     system=list_elem(l,0)->data.dict;
 151     loc=list_elem(l,0)->loc;
 152
 153     /* Arrange systemwide log facility */
 154     l=dict_lookup(system,"log");
 155     if (!l) {
 156         fatal("configuration does not include a system/log facility\n");
 157     }
 158     log=init_log(l);
 159     log->log(log->st,LOG_DEBUG,"setup: logging started");
 160
 161     /* Who are we supposed to run as? */
 162     userid=dict_read_string(system,"userid",False,"system",loc);
 163     if (userid) {
 164         do {
 165             pw=getpwent();
 166             if (pw && strcmp(pw->pw_name,userid)==0) {
 167                 uid=pw->pw_uid;
 168                 break;
 169             }
 170         } while(pw);
 171         endpwent();
 172         if (uid==0) {
 173             fatal("userid \"%s\" not found\n",userid);
 174         }
 175     }
 176
 177     /* Pidfile name */
 178     pidfile=dict_read_string(system,"pidfile",False,"system",loc);
 179
 180     /* Go along site list, starting sites */
 181     l=dict_lookup(config,"sites");
 182     if (!l) {
 183         fatal("configuration did not define any remote sites\n");
 184     }
 185     i=0;
 186     while ((site=list_elem(l, i++))) {
 187         struct site_if *s;
 188         if (site->type!=t_closure) {
 189             cfgfatal(site->loc,"system","non-closure in site list");
 190         }
 191         if (site->data.closure->type!=CL_SITE) {
 192             cfgfatal(site->loc,"system","non-site closure in site list");
 193         }
 194         s=site->data.closure->interface;
 195         s->control(s->st,True);
 196     }
 197 }
 198
 199 void register_for_poll(void *st, beforepoll_fn *before,
 200                        afterpoll_fn *after, uint32_t max_nfds, string_t desc)
 201 {
 202     struct poll_interest *i;
 203
 204     i=safe_malloc(sizeof(*i),"register_for_poll");
 205     i->before=before;
 206     i->after=after;
 207     i->state=st;
 208     i->max_nfds=max_nfds;
 209     i->nfds=0;
 210     i->desc=desc;
 211     total_nfds+=max_nfds;
 212     i->next=reg;
 213     reg=i;
 214     return;
 215 }
 216
 217 static void system_phase_hook(void *sst, uint32_t newphase)
 218 {
 219     if (newphase==PHASE_SHUTDOWN && pidfile) {
 220         /* Try to unlink the pidfile; don't care if it fails */
 221         unlink(pidfile);
 222     }
 223 }
 224
 225 static void run(void)
 226 {
 227     struct timeval tv_now;
 228     uint64_t now;
 229     struct poll_interest *i;
 230     int rv, nfds, remain, idx;
 231     int timeout;
 232     struct pollfd *fds;
 233
 234     fds=alloca(sizeof(*fds)*total_nfds);
 235     if (!fds) {
 236         fatal("run: couldn't alloca\n");
 237     }
 238
 239     while (!finished) {
 240         if (gettimeofday(&tv_now, NULL)!=0) {
 241             fatal_perror("main loop: gettimeofday");
 242         }
 243         now=(tv_now.tv_sec*1000)+(tv_now.tv_usec/1000);
 244         idx=0;
 245         for (i=reg; i; i=i->next) {
 246             i->after(i->state, fds+idx, i->nfds, &tv_now, &now);
 247             idx+=i->nfds;
 248         }
 249         remain=total_nfds;
 250         idx=0;
 251         timeout=-1;
 252         for (i=reg; i; i=i->next) {
 253             nfds=remain;
 254             rv=i->before(i->state, fds+idx, &nfds, &timeout, &tv_now, &now);
 255             if (rv!=0) {
 256                 /* XXX we need to handle this properly: increase the
 257                    nfds available */
 258                 fatal("run: beforepoll_fn (%s) returns %d\n",i->desc,rv);
 259             }
 260             if (timeout<-1) {
 261                 fatal("run: beforepoll_fn (%s) set timeout to %d\n",timeout);
 262             }
 263             idx+=nfds;
 264             remain-=nfds;
 265             i->nfds=nfds;
 266         }
 267         do {
 268             rv=poll(fds, idx, timeout);
 269             if (rv<0) {
 270                 if (errno!=EINTR) {
 271                     fatal_perror("run: poll");
 272                 }
 273             }
 274         } while (rv<0);
 275     }
 276 }
 277
 278 static void droppriv(void)
 279 {
 280     FILE *pf=NULL;
 281     pid_t p;
 282
 283     add_hook(PHASE_SHUTDOWN,system_phase_hook,NULL);
 284
 285     /* Background now, if we're supposed to: we may be unable to write the
 286        pidfile if we don't. */
 287     if (background) {
 288         printf("goto background\n");
 289         /* Open the pidfile before forking - that way the parent can tell
 290            whether it succeeds */
 291         if (pidfile) {
 292             pf=fopen(pidfile,"w");
 293             if (!pf) {
 294                 fatal_perror("cannot open pidfile \"%s\"",pidfile);
 295             }
 296         } else {
 297             Message(M_WARNING,"secnet: no pidfile configured, but "
 298                     "backgrounding anyway\n");
 299         }
 300         p=fork();
 301         if (p>0) {
 302             if (pf) {
 303                 /* Parent process - write pidfile, exit */
 304                 fprintf(pf,"%d\n",p);
 305                 fclose(pf);
 306             }
 307             exit(0);
 308         } else if (p==0) {
 309             /* Child process - all done, just carry on */
 310             if (pf) fclose(pf);
 311             printf("child\n");
 312         } else {
 313             /* Error */
 314             fatal_perror("cannot fork");
 315             exit(1);
 316         }
 317     } else {
 318         if (pidfile) {
 319             pf=fopen(pidfile,"w");
 320             if (!pf) {
 321                 fatal_perror("cannot open pidfile \"%s\"",pidfile);
 322             }
 323             fprintf(pf,"%d\n",getpid());
 324             fclose(pf);
 325         }
 326     }
 327
 328     /* Drop privilege now, if configured to do so */
 329     if (uid!=0) {
 330         if (setuid(uid)!=0) {
 331             fatal_perror("can't set uid to \"%s\"",userid);
 332         }
 333     }
 334 }
 335
 336 int main(int argc, char **argv)
 337 {
 338     dict_t *config;
 339
 340     enter_phase(PHASE_GETOPTS);
 341     parse_options(argc,argv);
 342
 343     enter_phase(PHASE_READCONFIG);
 344     config=read_conffile(configfile);
 345
 346     enter_phase(PHASE_SETUP);
 347     setup(config);
 348
 349     enter_phase(PHASE_DROPPRIV);
 350     droppriv();
 351
 352     enter_phase(PHASE_RUN);
 353     run();
 354
 355     enter_phase(PHASE_SHUTDOWN);
 356
 357     return 0;
 358 }
 359