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