xref: /freebsd/libexec/pppoed/pppoed.c (revision a35d88931c87cfe6bd38f01d7bad22140b3b38f3)
1 /*-
2  * Copyright (c) 1999-2001 Brian Somers <brian@Awfulhak.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/param.h>
30 #include <sys/socket.h>
31 #include <sys/un.h>
32 #include <netinet/in.h>
33 #include <arpa/inet.h>
34 #include <netdb.h>
35 #include <netgraph.h>
36 #include <net/ethernet.h>
37 #include <netinet/in_systm.h>
38 #include <netinet/ip.h>
39 #include <netgraph/ng_ether.h>
40 #include <netgraph/ng_message.h>
41 #include <netgraph/ng_pppoe.h>
42 #include <netgraph/ng_socket.h>
43 
44 #include <errno.h>
45 #include <paths.h>
46 #include <signal.h>
47 #include <stdio.h>
48 #include <stdarg.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <sysexits.h>
52 #include <sys/fcntl.h>
53 #ifndef NOKLDLOAD
54 #include <sys/linker.h>
55 #include <sys/module.h>
56 #endif
57 #include <sys/uio.h>
58 #include <sys/wait.h>
59 #include <syslog.h>
60 #include <termios.h>
61 #include <unistd.h>
62 
63 
64 #define	DEFAULT_EXEC_PREFIX	"exec /usr/sbin/ppp -direct "
65 #define	HISMACADDR		"HISMACADDR"
66 #define	SESSION_ID		"SESSION_ID"
67 
68 static void nglogx(const char *, ...) __printflike(1, 2);
69 
70 static int ReceivedSignal;
71 
72 static int
73 usage(const char *prog)
74 {
75   fprintf(stderr, "usage: %s [-Fd] [-P pidfile] [-a name] [-e exec | -l label]"
76           " [-p provider] interface\n", prog);
77   return EX_USAGE;
78 }
79 
80 static void
81 Farewell(int sig)
82 {
83   ReceivedSignal = sig;
84 }
85 
86 static int
87 ConfigureNode(const char *prog, const char *iface, const char *provider,
88               int cs, int ds, int debug, struct ngm_connect *ngc)
89 {
90   /*
91    * We're going to do this with the passed `ds' & `cs' descriptors:
92    *
93    * .---------.
94    * |  ether  |
95    * | <iface> |
96    * `---------'
97    *  (orphan)                                     ds    cs
98    *     |                                         |     |
99    *     |                                         |     |
100    * (ethernet)                                    |     |
101    * .---------.                                .-----------.
102    * |  pppoe  |                                |  socket   |
103    * | <iface> |(pppoe-<pid>)<---->(pppoe-<pid>)| <unnamed> |
104    * `---------                                 `-----------'
105    * (exec-<pid>)
106    *     ^                .-----------.      .-------------.
107    *     |                |   socket  |      | ppp -direct |
108    *     `--->(exec-<pid>)| <unnamed> |--fd--|  provider   |
109    *                      `-----------'      `-------------'
110    *
111    * where there are potentially many ppp processes running off of the
112    * same PPPoE node.
113    * The exec-<pid> hook isn't made 'till we Spawn().
114    */
115 
116   char *epath, *spath;
117   struct ngpppoe_init_data *data;
118   const struct hooklist *hlist;
119   const struct nodeinfo *ninfo;
120   const struct linkinfo *nlink;
121   struct ngm_mkpeer mkp;
122   struct ng_mesg *resp;
123   u_char rbuf[2048];
124   int f, plen;
125 
126   /*
127    * Ask for a list of hooks attached to the "ether" node.  This node should
128    * magically exist as a way of hooking stuff onto an ethernet device
129    */
130   epath = (char *)alloca(strlen(iface) + 2);
131   sprintf(epath, "%s:", iface);
132 
133   if (debug)
134     fprintf(stderr, "Sending NGM_LISTHOOKS to %s\n", epath);
135 
136   if (NgSendMsg(cs, epath, NGM_GENERIC_COOKIE, NGM_LISTHOOKS, NULL, 0) < 0) {
137     if (errno == ENOENT)
138       fprintf(stderr, "%s Cannot send a netgraph message: Invalid interface\n",
139               epath);
140     else
141       fprintf(stderr, "%s Cannot send a netgraph message: %s\n",
142               epath, strerror(errno));
143     return EX_UNAVAILABLE;
144   }
145 
146   /* Get our list back */
147   resp = (struct ng_mesg *)rbuf;
148   if (NgRecvMsg(cs, resp, sizeof rbuf, NULL) <= 0) {
149     perror("Cannot get netgraph response");
150     return EX_UNAVAILABLE;
151   }
152 
153   hlist = (const struct hooklist *)resp->data;
154   ninfo = &hlist->nodeinfo;
155 
156   if (debug)
157     fprintf(stderr, "Got reply from id [%x]: Type %s with %d hooks\n",
158             ninfo->id, ninfo->type, ninfo->hooks);
159 
160   /* Make sure we've got the right type of node */
161   if (strncmp(ninfo->type, NG_ETHER_NODE_TYPE, sizeof NG_ETHER_NODE_TYPE - 1)) {
162     fprintf(stderr, "%s Unexpected node type ``%s'' (wanted ``"
163             NG_ETHER_NODE_TYPE "'')\n", epath, ninfo->type);
164     return EX_DATAERR;
165   }
166 
167   /* look for a hook already attached.  */
168   for (f = 0; f < ninfo->hooks; f++) {
169     nlink = &hlist->link[f];
170 
171     if (debug)
172       fprintf(stderr, "  Got [%x]:%s -> [%x]:%s\n", ninfo->id,
173               nlink->ourhook, nlink->nodeinfo.id, nlink->peerhook);
174 
175     if (!strcmp(nlink->ourhook, NG_ETHER_HOOK_ORPHAN) ||
176         !strcmp(nlink->ourhook, NG_ETHER_HOOK_DIVERT)) {
177       /*
178        * Something is using the data coming out of this `ether' node.
179        * If it's a PPPoE node, we use that node, otherwise we complain that
180        * someone else is using the node.
181        */
182       if (strcmp(nlink->nodeinfo.type, NG_PPPOE_NODE_TYPE)) {
183         fprintf(stderr, "%s Node type %s is currently active\n",
184                 epath, nlink->nodeinfo.type);
185         return EX_UNAVAILABLE;
186       }
187       break;
188     }
189   }
190 
191   if (f == ninfo->hooks) {
192     /*
193      * Create a new PPPoE node connected to the `ether' node using
194      * the magic `orphan' and `ethernet' hooks
195      */
196     snprintf(mkp.type, sizeof mkp.type, "%s", NG_PPPOE_NODE_TYPE);
197     snprintf(mkp.ourhook, sizeof mkp.ourhook, "%s", NG_ETHER_HOOK_ORPHAN);
198     snprintf(mkp.peerhook, sizeof mkp.peerhook, "%s", NG_PPPOE_HOOK_ETHERNET);
199 
200     if (debug)
201       fprintf(stderr, "Send MKPEER: %s%s -> [type %s]:%s\n", epath,
202               mkp.ourhook, mkp.type, mkp.peerhook);
203 
204     if (NgSendMsg(cs, epath, NGM_GENERIC_COOKIE,
205                   NGM_MKPEER, &mkp, sizeof mkp) < 0) {
206       fprintf(stderr, "%s Cannot create a peer PPPoE node: %s\n",
207               epath, strerror(errno));
208       return EX_OSERR;
209     }
210   }
211 
212   /* Connect the PPPoE node to our socket node.  */
213   snprintf(ngc->path, sizeof ngc->path, "%s%s", epath, NG_ETHER_HOOK_ORPHAN);
214   snprintf(ngc->ourhook, sizeof ngc->ourhook, "pppoe-%ld", (long)getpid());
215   memcpy(ngc->peerhook, ngc->ourhook, sizeof ngc->peerhook);
216 
217   if (NgSendMsg(cs, ".:", NGM_GENERIC_COOKIE,
218                 NGM_CONNECT, ngc, sizeof *ngc) < 0) {
219     perror("Cannot CONNECT PPPoE and socket nodes");
220     return EX_OSERR;
221   }
222 
223   plen = strlen(provider);
224 
225   data = (struct ngpppoe_init_data *)alloca(sizeof *data + plen);
226   snprintf(data->hook, sizeof data->hook, "%s", ngc->peerhook);
227   memcpy(data->data, provider, plen);
228   data->data_len = plen;
229 
230   spath = (char *)alloca(strlen(ngc->peerhook) + 3);
231   strcpy(spath, ".:");
232   strcpy(spath + 2, ngc->ourhook);
233 
234   if (debug) {
235     if (provider)
236       fprintf(stderr, "Sending PPPOE_LISTEN to %s, provider %s\n",
237               spath, provider);
238     else
239       fprintf(stderr, "Sending PPPOE_LISTEN to %s\n", spath);
240   }
241 
242   if (NgSendMsg(cs, spath, NGM_PPPOE_COOKIE, NGM_PPPOE_LISTEN,
243                 data, sizeof *data + plen) == -1) {
244     fprintf(stderr, "%s: Cannot LISTEN on netgraph node: %s\n",
245             spath, strerror(errno));
246     return EX_OSERR;
247   }
248 
249   return 0;
250 }
251 
252 static void
253 Spawn(const char *prog, const char *acname, const char *provider,
254       const char *exec, struct ngm_connect ngc, int cs, int ds, void *request,
255       int sz, int debug)
256 {
257   char msgbuf[sizeof(struct ng_mesg) + sizeof(struct ngpppoe_sts)];
258   struct ng_mesg *rep = (struct ng_mesg *)msgbuf;
259   struct ngpppoe_sts *sts = (struct ngpppoe_sts *)(msgbuf + sizeof *rep);
260   struct ngpppoe_init_data *data;
261   char env[sizeof(HISMACADDR)+18], unknown[14], sessionid[5], *path;
262   unsigned char *macaddr;
263   const char *msg;
264   int ret, slen;
265 
266   switch ((ret = fork())) {
267     case -1:
268       syslog(LOG_ERR, "fork: %m");
269       break;
270 
271     case 0:
272       switch (fork()) {
273         case 0:
274           break;
275         case -1:
276           _exit(errno);
277         default:
278           _exit(0);
279       }
280       close(cs);
281       close(ds);
282 
283       /* Create a new socket node */
284       if (debug)
285         syslog(LOG_INFO, "Creating a new socket node");
286 
287       if (NgMkSockNode(NULL, &cs, &ds) == -1) {
288         syslog(LOG_ERR, "Cannot create netgraph socket node: %m");
289         _exit(EX_CANTCREAT);
290       }
291 
292       /* Connect the PPPoE node to our new socket node.  */
293       snprintf(ngc.ourhook, sizeof ngc.ourhook, "exec-%ld", (long)getpid());
294       memcpy(ngc.peerhook, ngc.ourhook, sizeof ngc.peerhook);
295 
296       if (debug)
297         syslog(LOG_INFO, "Sending CONNECT from .:%s -> %s.%s",
298                ngc.ourhook, ngc.path, ngc.peerhook);
299       if (NgSendMsg(cs, ".:", NGM_GENERIC_COOKIE,
300                     NGM_CONNECT, &ngc, sizeof ngc) < 0) {
301         syslog(LOG_ERR, "Cannot CONNECT PPPoE and socket nodes: %m");
302         _exit(EX_OSERR);
303       }
304 
305       /*
306        * If we tell the socket node not to LINGER, it will go away when
307        * the last hook is removed.
308        */
309       if (debug)
310         syslog(LOG_INFO, "Sending NGM_SOCK_CMD_NOLINGER to socket");
311       if (NgSendMsg(cs, ".:", NGM_SOCKET_COOKIE,
312                     NGM_SOCK_CMD_NOLINGER, NULL, 0) < 0) {
313         syslog(LOG_ERR, "Cannot send NGM_SOCK_CMD_NOLINGER: %m");
314         _exit(EX_OSERR);
315       }
316 
317       /* Put the PPPoE node into OFFER mode */
318       slen = strlen(acname);
319       data = (struct ngpppoe_init_data *)alloca(sizeof *data + slen);
320       snprintf(data->hook, sizeof data->hook, "%s", ngc.ourhook);
321       memcpy(data->data, acname, slen);
322       data->data_len = slen;
323 
324       path = (char *)alloca(strlen(ngc.ourhook) + 3);
325       strcpy(path, ".:");
326       strcpy(path + 2, ngc.ourhook);
327 
328       syslog(LOG_INFO, "Offering to %s as access concentrator %s",
329              path, acname);
330       if (NgSendMsg(cs, path, NGM_PPPOE_COOKIE, NGM_PPPOE_OFFER,
331                     data, sizeof *data + slen) == -1) {
332         syslog(LOG_INFO, "%s: Cannot OFFER on netgraph node: %m", path);
333         _exit(EX_OSERR);
334       }
335       /* If we have a provider code, set it */
336       if (provider) {
337         slen = strlen(provider);
338         data = (struct ngpppoe_init_data *)alloca(sizeof *data + slen);
339         snprintf(data->hook, sizeof data->hook, "%s", ngc.ourhook);
340         memcpy(data->data, provider, slen);
341         data->data_len = slen;
342 
343         syslog(LOG_INFO, "adding to %s as offered service %s",
344              path, acname);
345         if (NgSendMsg(cs, path, NGM_PPPOE_COOKIE, NGM_PPPOE_SERVICE,
346                     data, sizeof *data + slen) == -1) {
347           syslog(LOG_INFO, "%s: Cannot add service on netgraph node: %m", path);
348           _exit(EX_OSERR);
349         }
350       }
351 
352       /* Put the peer's MAC address in the environment */
353       if (sz >= sizeof(struct ether_header)) {
354         macaddr = ((struct ether_header *)request)->ether_shost;
355         snprintf(env, sizeof(env), "%s=%x:%x:%x:%x:%x:%x", HISMACADDR,
356                  macaddr[0], macaddr[1], macaddr[2], macaddr[3], macaddr[4],
357                  macaddr[5]);
358         if (putenv(env) != 0)
359           syslog(LOG_INFO, "putenv: cannot set %s: %m", env);
360       }
361 
362       /* And send our request data to the waiting node */
363       if (debug)
364         syslog(LOG_INFO, "Sending original request to %s (%d bytes)", path, sz);
365       if (NgSendData(ds, ngc.ourhook, request, sz) == -1) {
366         syslog(LOG_ERR, "Cannot send original request to %s: %m", path);
367         _exit(EX_OSERR);
368       }
369 
370       /* Then wait for a success indication */
371 
372       if (debug)
373         syslog(LOG_INFO, "Waiting for a SUCCESS reply %s", path);
374 
375       do {
376         if ((ret = NgRecvMsg(cs, rep, sizeof msgbuf, NULL)) < 0) {
377           syslog(LOG_ERR, "%s: Cannot receive a message: %m", path);
378           _exit(EX_OSERR);
379         }
380 
381         if (ret == 0) {
382           /* The socket has been closed */
383           syslog(LOG_INFO, "%s: Client timed out", path);
384           _exit(EX_TEMPFAIL);
385         }
386 
387         if (rep->header.version != NG_VERSION) {
388           syslog(LOG_ERR, "%ld: Unexpected netgraph version, expected %ld",
389                  (long)rep->header.version, (long)NG_VERSION);
390           _exit(EX_PROTOCOL);
391         }
392 
393         if (rep->header.typecookie != NGM_PPPOE_COOKIE) {
394           syslog(LOG_INFO, "%ld: Unexpected netgraph cookie, expected %ld",
395                  (long)rep->header.typecookie, (long)NGM_PPPOE_COOKIE);
396           continue;
397         }
398 
399         switch (rep->header.cmd) {
400           case NGM_PPPOE_SET_FLAG:	msg = "SET_FLAG";	break;
401           case NGM_PPPOE_CONNECT:	msg = "CONNECT";	break;
402           case NGM_PPPOE_LISTEN:	msg = "LISTEN";		break;
403           case NGM_PPPOE_OFFER:		msg = "OFFER";		break;
404           case NGM_PPPOE_SUCCESS:	msg = "SUCCESS";	break;
405           case NGM_PPPOE_FAIL:		msg = "FAIL";		break;
406           case NGM_PPPOE_CLOSE:		msg = "CLOSE";		break;
407           case NGM_PPPOE_GET_STATUS:	msg = "GET_STATUS";	break;
408           case NGM_PPPOE_ACNAME:
409             msg = "ACNAME";
410             if (setenv("ACNAME", sts->hook, 1) != 0)
411               syslog(LOG_WARNING, "setenv: cannot set ACNAME=%s: %m",
412                      sts->hook);
413             break;
414           case NGM_PPPOE_SESSIONID:
415             msg = "SESSIONID";
416             snprintf(sessionid, sizeof sessionid, "%04x", *(u_int16_t *)sts);
417             if (setenv("SESSIONID", sessionid, 1) != 0)
418               syslog(LOG_WARNING, "setenv: cannot set SESSIONID=%s: %m",
419                      sessionid);
420             break;
421           default:
422             snprintf(unknown, sizeof unknown, "<%d>", (int)rep->header.cmd);
423             msg = unknown;
424             break;
425         }
426 
427         switch (rep->header.cmd) {
428           case NGM_PPPOE_FAIL:
429           case NGM_PPPOE_CLOSE:
430             syslog(LOG_ERR, "Received NGM_PPPOE_%s (hook \"%s\")",
431                    msg, sts->hook);
432             _exit(0);
433         }
434 
435         syslog(LOG_INFO, "Received NGM_PPPOE_%s (hook \"%s\")", msg, sts->hook);
436       } while (rep->header.cmd != NGM_PPPOE_SUCCESS);
437 
438       dup2(ds, STDIN_FILENO);
439       dup2(ds, STDOUT_FILENO);
440       close(ds);
441       close(cs);
442 
443       setsid();
444       syslog(LOG_INFO, "Executing: %s", exec);
445       execlp(_PATH_BSHELL, _PATH_BSHELL, "-c", exec, (char *)NULL);
446       syslog(LOG_ERR, "execlp failed: %m");
447       _exit(EX_OSFILE);
448 
449     default:
450       wait(&ret);
451       errno = ret;
452       if (errno)
453         syslog(LOG_ERR, "Second fork failed: %m");
454       break;
455   }
456 }
457 
458 #ifndef NOKLDLOAD
459 static int
460 LoadModules(void)
461 {
462   const char *module[] = { "netgraph", "ng_socket", "ng_ether", "ng_pppoe" };
463   int f;
464 
465   for (f = 0; f < sizeof module / sizeof *module; f++)
466     if (modfind(module[f]) == -1 && kldload(module[f]) == -1) {
467       fprintf(stderr, "kldload: %s: %s\n", module[f], strerror(errno));
468       return 0;
469     }
470 
471   return 1;
472 }
473 #endif
474 
475 static void
476 nglog(const char *fmt, ...)
477 {
478   char nfmt[256];
479   va_list ap;
480 
481   snprintf(nfmt, sizeof nfmt, "%s: %s", fmt, strerror(errno));
482   va_start(ap, fmt);
483   vsyslog(LOG_INFO, nfmt, ap);
484   va_end(ap);
485 }
486 
487 static void
488 nglogx(const char *fmt, ...)
489 {
490   va_list ap;
491 
492   va_start(ap, fmt);
493   vsyslog(LOG_INFO, fmt, ap);
494   va_end(ap);
495 }
496 
497 int
498 main(int argc, char *argv[])
499 {
500   char hostname[MAXHOSTNAMELEN], *exec, rhook[NG_HOOKSIZ];
501   unsigned char response[1024];
502   const char *label, *prog, *provider, *acname;
503   struct ngm_connect ngc;
504   struct sigaction act;
505   int ch, cs, ds, ret, optF, optd, optn, sz, f;
506   const char *pidfile;
507 
508   prog = strrchr(argv[0], '/');
509   prog = prog ? prog + 1 : argv[0];
510   pidfile = NULL;
511   exec = NULL;
512   label = NULL;
513   acname = NULL;
514   provider = "";
515   optF = optd = optn = 0;
516 
517   while ((ch = getopt(argc, argv, "FP:a:de:l:n:p:")) != -1) {
518     switch (ch) {
519       case 'F':
520         optF = 1;
521         break;
522 
523       case 'P':
524         pidfile = optarg;
525         break;
526 
527       case 'a':
528         acname = optarg;
529         break;
530 
531       case 'd':
532         optd = 1;
533         break;
534 
535       case 'e':
536         exec = optarg;
537         break;
538 
539       case 'l':
540         label = optarg;
541         break;
542 
543       case 'n':
544         optn = 1;
545         NgSetDebug(atoi(optarg));
546         break;
547 
548       case 'p':
549         provider = optarg;
550         break;
551 
552       default:
553         return usage(prog);
554     }
555   }
556 
557   if (optind >= argc || optind + 2 < argc)
558     return usage(prog);
559 
560   if (exec != NULL && label != NULL)
561     return usage(prog);
562 
563   if (exec == NULL) {
564     if (label == NULL)
565       label = provider;
566     if (label == NULL) {
567       fprintf(stderr, "%s: Either a provider, a label or an exec command"
568               " must be given\n", prog);
569       return usage(prog);
570     }
571     exec = (char *)alloca(sizeof DEFAULT_EXEC_PREFIX + strlen(label));
572     if (exec == NULL) {
573       fprintf(stderr, "%s: Cannot allocate %d bytes\n", prog,
574               (int)(sizeof DEFAULT_EXEC_PREFIX) + strlen(label));
575       return EX_OSERR;
576     }
577     strcpy(exec, DEFAULT_EXEC_PREFIX);
578     strcpy(exec + sizeof DEFAULT_EXEC_PREFIX - 1, label);
579   }
580 
581   if (acname == NULL) {
582     char *dot;
583 
584     if (gethostname(hostname, sizeof hostname))
585       strcpy(hostname, "localhost");
586     else if ((dot = strchr(hostname, '.')))
587       *dot = '\0';
588 
589     acname = hostname;
590   }
591 
592 #ifndef NOKLDLOAD
593   if (!LoadModules())
594     return EX_UNAVAILABLE;
595 #endif
596 
597   /* Create a socket node */
598   if (NgMkSockNode(NULL, &cs, &ds) == -1) {
599     perror("Cannot create netgraph socket node");
600     return EX_CANTCREAT;
601   }
602 
603   /* Connect it up (and fill in `ngc') */
604   if ((ret = ConfigureNode(prog, argv[optind], provider, cs, ds,
605                            optd, &ngc)) != 0) {
606     close(cs);
607     close(ds);
608     return ret;
609   }
610 
611   if (!optF && daemon(1, 0) == -1) {
612     perror("daemon()");
613     close(cs);
614     close(ds);
615     return EX_OSERR;
616   }
617 
618 
619   if (pidfile != NULL) {
620     FILE *fp;
621 
622     if ((fp = fopen(pidfile, "w")) == NULL) {
623       perror(pidfile);
624       close(cs);
625       close(ds);
626       return EX_CANTCREAT;
627     } else {
628       fprintf(fp, "%d\n", (int)getpid());
629       fclose(fp);
630     }
631   }
632 
633   openlog(prog, LOG_PID | (optF ? LOG_PERROR : 0), LOG_DAEMON);
634   if (!optF && optn)
635     NgSetErrLog(nglog, nglogx);
636 
637   memset(&act, '\0', sizeof act);
638   act.sa_handler = Farewell;
639   act.sa_flags = 0;
640   sigemptyset(&act.sa_mask);
641   sigaction(SIGHUP, &act, NULL);
642   sigaction(SIGINT, &act, NULL);
643   sigaction(SIGQUIT, &act, NULL);
644   sigaction(SIGTERM, &act, NULL);
645 
646   while (!ReceivedSignal) {
647     if (*provider)
648       syslog(LOG_INFO, "Listening as provider %s", provider);
649     else
650       syslog(LOG_INFO, "Listening");
651 
652     switch (sz = NgRecvData(ds, response, sizeof response, rhook)) {
653       case -1:
654         syslog(LOG_INFO, "NgRecvData: %m");
655         break;
656       case 0:
657         syslog(LOG_INFO, "NgRecvData: socket closed");
658         break;
659       default:
660         if (optd) {
661           char *dbuf, *ptr;
662 
663           ptr = dbuf = alloca(sz * 2 + 1);
664           for (f = 0; f < sz; f++, ptr += 2)
665             sprintf(ptr, "%02x", (u_char)response[f]);
666           *ptr = '\0';
667           syslog(LOG_INFO, "Got %d bytes of data: %s", sz, dbuf);
668         }
669     }
670     if (sz <= 0) {
671       ret = EX_UNAVAILABLE;
672       break;
673     }
674     Spawn(prog, acname, provider, exec, ngc, cs, ds, response, sz, optd);
675   }
676 
677   if (pidfile)
678     remove(pidfile);
679 
680   if (ReceivedSignal) {
681     syslog(LOG_INFO, "Received signal %d, exiting", ReceivedSignal);
682 
683     signal(ReceivedSignal, SIG_DFL);
684     raise(ReceivedSignal);
685 
686     /* NOTREACHED */
687 
688     ret = -ReceivedSignal;
689   }
690 
691   return ret;
692 }
693