1 /*
2 * options.c - handles option processing for PPP.
3 *
4 * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 *
18 * 3. The name "Carnegie Mellon University" must not be used to
19 * endorse or promote products derived from this software without
20 * prior written permission. For permission or any legal
21 * details, please contact
22 * Office of Technology Transfer
23 * Carnegie Mellon University
24 * 5000 Forbes Avenue
25 * Pittsburgh, PA 15213-3890
26 * (412) 268-4387, fax: (412) 268-7395
27 * tech-transfer@andrew.cmu.edu
28 *
29 * 4. Redistributions of any form whatsoever must retain the following
30 * acknowledgment:
31 * "This product includes software developed by Computing Services
32 * at Carnegie Mellon University (http://www.cmu.edu/computing/)."
33 *
34 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
35 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
36 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
37 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
38 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
39 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
40 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
41 */
42
43 #define RCSID "$Id: options.c,v 1.102 2008/06/15 06:53:06 paulus Exp $"
44
45 #include <ctype.h>
46 #include <stdio.h>
47 #include <errno.h>
48 #include <unistd.h>
49 #include <fcntl.h>
50 #include <stdlib.h>
51 #include <syslog.h>
52 #include <string.h>
53 #include <pwd.h>
54 #ifdef PLUGIN
55 #include <dlfcn.h>
56 #endif
57
58 #ifdef PPP_FILTER
59 #include <pcap.h>
60 /*
61 * There have been 3 or 4 different names for this in libpcap CVS, but
62 * this seems to be what they have settled on...
63 * For older versions of libpcap, use DLT_PPP - but that means
64 * we lose the inbound and outbound qualifiers.
65 */
66 #ifndef DLT_PPP_PPPD
67 #ifdef DLT_PPP_WITHDIRECTION
68 #define DLT_PPP_PPPD DLT_PPP_WITHDIRECTION
69 #else
70 #define DLT_PPP_PPPD DLT_PPP
71 #endif
72 #endif
73 #endif /* PPP_FILTER */
74
75 #include "pppd.h"
76 #include "pathnames.h"
77
78 #if defined(ultrix) || defined(NeXT)
79 char *strdup __P((char *));
80 #endif
81
82 static const char rcsid[] = RCSID;
83
84 struct option_value {
85 struct option_value *next;
86 const char *source;
87 char value[1];
88 };
89
90 /*
91 * Option variables and default values.
92 */
93 int debug = 0; /* Debug flag */
94 int kdebugflag = 0; /* Tell kernel to print debug messages */
95 int default_device = 1; /* Using /dev/tty or equivalent */
96 char devnam[MAXPATHLEN]; /* Device name */
97 bool nodetach = 0; /* Don't detach from controlling tty */
98 bool updetach = 0; /* Detach once link is up */
99 bool master_detach; /* Detach when we're (only) multilink master */
100 int maxconnect = 0; /* Maximum connect time */
101 char user[MAXNAMELEN]; /* Username for PAP */
102 char passwd[MAXSECRETLEN]; /* Password for PAP */
103 bool persist = 0; /* Reopen link after it goes down */
104 char our_name[MAXNAMELEN]; /* Our name for authentication purposes */
105 bool demand = 0; /* do dial-on-demand */
106 char *ipparam = NULL; /* Extra parameter for ip up/down scripts */
107 int idle_time_limit = 0; /* Disconnect if idle for this many seconds */
108 int holdoff = 30; /* # seconds to pause before reconnecting */
109 bool holdoff_specified; /* true if a holdoff value has been given */
110 int log_to_fd = 1; /* send log messages to this fd too */
111 bool log_default = 1; /* log_to_fd is default (stdout) */
112 int maxfail = 10; /* max # of unsuccessful connection attempts */
113 char linkname[MAXPATHLEN]; /* logical name for link */
114 bool tune_kernel; /* may alter kernel settings */
115 int connect_delay = 1000; /* wait this many ms after connect script */
116 int req_unit = -1; /* requested interface unit */
117 bool multilink = 0; /* Enable multilink operation */
118 char *bundle_name = NULL; /* bundle name for multilink */
119 bool dump_options; /* print out option values */
120 bool dryrun; /* print out option values and exit */
121 char *domain; /* domain name set by domain option */
122 int child_wait = 5; /* # seconds to wait for children at exit */
123 struct userenv *userenv_list; /* user environment variables */
124
125 #ifdef MAXOCTETS
126 unsigned int maxoctets = 0; /* default - no limit */
127 int maxoctets_dir = 0; /* default - sum of traffic */
128 int maxoctets_timeout = 1; /* default 1 second */
129 #endif
130
131
132 extern option_t auth_options[];
133 extern struct stat devstat;
134
135 #ifdef PPP_FILTER
136 struct bpf_program pass_filter;/* Filter program for packets to pass */
137 struct bpf_program active_filter; /* Filter program for link-active pkts */
138 #endif
139
140 static option_t *curopt; /* pointer to option being processed */
141 char *current_option; /* the name of the option being parsed */
142 int privileged_option; /* set iff the current option came from root */
143 char *option_source; /* string saying where the option came from */
144 int option_priority = OPRIO_CFGFILE; /* priority of the current options */
145 bool devnam_fixed; /* can no longer change device name */
146
147 static int logfile_fd = -1; /* fd opened for log file */
148 static char logfile_name[MAXPATHLEN]; /* name of log file */
149
150 /*
151 * Prototypes
152 */
153 static int setdomain __P((char **));
154 static int readfile __P((char **));
155 static int callfile __P((char **));
156 static int showversion __P((char **));
157 static int showhelp __P((char **));
158 static void usage __P((void));
159 static int setlogfile __P((char **));
160 #ifdef PLUGIN
161 static int loadplugin __P((char **));
162 #endif
163
164 #ifdef PPP_FILTER
165 static int setpassfilter __P((char **));
166 static int setactivefilter __P((char **));
167 #endif
168
169 #ifdef MAXOCTETS
170 static int setmodir __P((char **));
171 #endif
172
173 static int user_setenv __P((char **));
174 static void user_setprint __P((option_t *, printer_func, void *));
175 static int user_unsetenv __P((char **));
176 static void user_unsetprint __P((option_t *, printer_func, void *));
177
178 static option_t *find_option __P((const char *name));
179 static int process_option __P((option_t *, char *, char **));
180 static int n_arguments __P((option_t *));
181 static int number_option __P((char *, u_int32_t *, int));
182
183 /*
184 * Structure to store extra lists of options.
185 */
186 struct option_list {
187 option_t *options;
188 struct option_list *next;
189 };
190
191 static struct option_list *extra_options = NULL;
192
193 /*
194 * Valid arguments.
195 */
196 option_t general_options[] = {
197 { "debug", o_int, &debug,
198 "Increase debugging level", OPT_INC | OPT_NOARG | 1 },
199 { "-d", o_int, &debug,
200 "Increase debugging level",
201 OPT_ALIAS | OPT_INC | OPT_NOARG | 1 },
202
203 { "kdebug", o_int, &kdebugflag,
204 "Set kernel driver debug level", OPT_PRIO },
205
206 { "nodetach", o_bool, &nodetach,
207 "Don't detach from controlling tty", OPT_PRIO | 1 },
208 { "-detach", o_bool, &nodetach,
209 "Don't detach from controlling tty", OPT_ALIAS | OPT_PRIOSUB | 1 },
210 { "updetach", o_bool, &updetach,
211 "Detach from controlling tty once link is up",
212 OPT_PRIOSUB | OPT_A2CLR | 1, &nodetach },
213
214 { "master_detach", o_bool, &master_detach,
215 "Detach when we're multilink master but have no link", 1 },
216
217 { "holdoff", o_int, &holdoff,
218 "Set time in seconds before retrying connection",
219 OPT_PRIO, &holdoff_specified },
220
221 { "idle", o_int, &idle_time_limit,
222 "Set time in seconds before disconnecting idle link", OPT_PRIO },
223
224 { "maxconnect", o_int, &maxconnect,
225 "Set connection time limit",
226 OPT_PRIO | OPT_LLIMIT | OPT_NOINCR | OPT_ZEROINF },
227
228 { "domain", o_special, (void *)setdomain,
229 "Add given domain name to hostname",
230 OPT_PRIO | OPT_PRIV | OPT_A2STRVAL, &domain },
231
232 { "file", o_special, (void *)readfile,
233 "Take options from a file", OPT_NOPRINT },
234 { "call", o_special, (void *)callfile,
235 "Take options from a privileged file", OPT_NOPRINT },
236
237 { "persist", o_bool, &persist,
238 "Keep on reopening connection after close", OPT_PRIO | 1 },
239 { "nopersist", o_bool, &persist,
240 "Turn off persist option", OPT_PRIOSUB },
241
242 { "demand", o_bool, &demand,
243 "Dial on demand", OPT_INITONLY | 1, &persist },
244
245 { "--version", o_special_noarg, (void *)showversion,
246 "Show version number" },
247 { "--help", o_special_noarg, (void *)showhelp,
248 "Show brief listing of options" },
249 { "-h", o_special_noarg, (void *)showhelp,
250 "Show brief listing of options", OPT_ALIAS },
251
252 { "logfile", o_special, (void *)setlogfile,
253 "Append log messages to this file",
254 OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, &logfile_name },
255 { "logfd", o_int, &log_to_fd,
256 "Send log messages to this file descriptor",
257 OPT_PRIOSUB | OPT_A2CLR, &log_default },
258 { "nolog", o_int, &log_to_fd,
259 "Don't send log messages to any file",
260 OPT_PRIOSUB | OPT_NOARG | OPT_VAL(-1) },
261 { "nologfd", o_int, &log_to_fd,
262 "Don't send log messages to any file descriptor",
263 OPT_PRIOSUB | OPT_ALIAS | OPT_NOARG | OPT_VAL(-1) },
264
265 { "linkname", o_string, linkname,
266 "Set logical name for link",
267 OPT_PRIO | OPT_PRIV | OPT_STATIC, NULL, MAXPATHLEN },
268
269 { "maxfail", o_int, &maxfail,
270 "Maximum number of unsuccessful connection attempts to allow",
271 OPT_PRIO },
272
273 { "ktune", o_bool, &tune_kernel,
274 "Alter kernel settings as necessary", OPT_PRIO | 1 },
275 { "noktune", o_bool, &tune_kernel,
276 "Don't alter kernel settings", OPT_PRIOSUB },
277
278 { "connect-delay", o_int, &connect_delay,
279 "Maximum time (in ms) to wait after connect script finishes",
280 OPT_PRIO },
281
282 { "unit", o_int, &req_unit,
283 "PPP interface unit number to use if possible",
284 OPT_PRIO | OPT_LLIMIT, 0, 0 },
285
286 { "dump", o_bool, &dump_options,
287 "Print out option values after parsing all options", 1 },
288 { "dryrun", o_bool, &dryrun,
289 "Stop after parsing, printing, and checking options", 1 },
290
291 { "child-timeout", o_int, &child_wait,
292 "Number of seconds to wait for child processes at exit",
293 OPT_PRIO },
294
295 { "set", o_special, (void *)user_setenv,
296 "Set user environment variable",
297 OPT_A2PRINTER | OPT_NOPRINT, (void *)user_setprint },
298 { "unset", o_special, (void *)user_unsetenv,
299 "Unset user environment variable",
300 OPT_A2PRINTER | OPT_NOPRINT, (void *)user_unsetprint },
301
302 #ifdef HAVE_MULTILINK
303 { "multilink", o_bool, &multilink,
304 "Enable multilink operation", OPT_PRIO | 1 },
305 { "mp", o_bool, &multilink,
306 "Enable multilink operation", OPT_PRIOSUB | OPT_ALIAS | 1 },
307 { "nomultilink", o_bool, &multilink,
308 "Disable multilink operation", OPT_PRIOSUB | 0 },
309 { "nomp", o_bool, &multilink,
310 "Disable multilink operation", OPT_PRIOSUB | OPT_ALIAS | 0 },
311
312 { "bundle", o_string, &bundle_name,
313 "Bundle name for multilink", OPT_PRIO },
314 #endif /* HAVE_MULTILINK */
315
316 #ifdef PLUGIN
317 { "plugin", o_special, (void *)loadplugin,
318 "Load a plug-in module into pppd", OPT_PRIV | OPT_A2LIST },
319 #endif
320
321 #ifdef PPP_FILTER
322 { "pass-filter", o_special, setpassfilter,
323 "set filter for packets to pass", OPT_PRIO },
324
325 { "active-filter", o_special, setactivefilter,
326 "set filter for active pkts", OPT_PRIO },
327 #endif
328
329 #ifdef MAXOCTETS
330 { "maxoctets", o_int, &maxoctets,
331 "Set connection traffic limit",
332 OPT_PRIO | OPT_LLIMIT | OPT_NOINCR | OPT_ZEROINF },
333 { "mo", o_int, &maxoctets,
334 "Set connection traffic limit",
335 OPT_ALIAS | OPT_PRIO | OPT_LLIMIT | OPT_NOINCR | OPT_ZEROINF },
336 { "mo-direction", o_special, setmodir,
337 "Set direction for limit traffic (sum,in,out,max)" },
338 { "mo-timeout", o_int, &maxoctets_timeout,
339 "Check for traffic limit every N seconds", OPT_PRIO | OPT_LLIMIT | 1 },
340 #endif
341
342 { NULL }
343 };
344
345 #ifndef IMPLEMENTATION
346 #define IMPLEMENTATION ""
347 #endif
348
349 static char *usage_string = "\
350 pppd version %s\n\
351 Usage: %s [ options ], where options are:\n\
352 <device> Communicate over the named device\n\
353 <speed> Set the baud rate to <speed>\n\
354 <loc>:<rem> Set the local and/or remote interface IP\n\
355 addresses. Either one may be omitted.\n\
356 asyncmap <n> Set the desired async map to hex <n>\n\
357 auth Require authentication from peer\n\
358 connect <p> Invoke shell command <p> to set up the serial line\n\
359 crtscts Use hardware RTS/CTS flow control\n\
360 defaultroute Add default route through interface\n\
361 file <f> Take options from file <f>\n\
362 modem Use modem control lines\n\
363 mru <n> Set MRU value to <n> for negotiation\n\
364 See pppd(8) for more options.\n\
365 ";
366
367 /*
368 * parse_args - parse a string of arguments from the command line.
369 */
370 int
parse_args(argc,argv)371 parse_args(argc, argv)
372 int argc;
373 char **argv;
374 {
375 char *arg;
376 option_t *opt;
377 int n;
378
379 privileged_option = privileged;
380 option_source = "command line";
381 option_priority = OPRIO_CMDLINE;
382 while (argc > 0) {
383 arg = *argv++;
384 --argc;
385 opt = find_option(arg);
386 if (opt == NULL) {
387 option_error("unrecognized option '%s'", arg);
388 usage();
389 return 0;
390 }
391 n = n_arguments(opt);
392 if (argc < n) {
393 option_error("too few parameters for option %s", arg);
394 return 0;
395 }
396 if (!process_option(opt, arg, argv))
397 return 0;
398 argc -= n;
399 argv += n;
400 }
401 return 1;
402 }
403
404 /*
405 * options_from_file - Read a string of options from a file,
406 * and interpret them.
407 */
408 int
options_from_file(filename,must_exist,check_prot,priv)409 options_from_file(filename, must_exist, check_prot, priv)
410 char *filename;
411 int must_exist;
412 int check_prot;
413 int priv;
414 {
415 FILE *f;
416 int i, newline, ret, err;
417 option_t *opt;
418 int oldpriv, n;
419 char *oldsource;
420 uid_t euid;
421 char *argv[MAXARGS];
422 char args[MAXARGS][MAXWORDLEN];
423 char cmd[MAXWORDLEN];
424
425 euid = geteuid();
426 if (check_prot && seteuid(getuid()) == -1) {
427 option_error("unable to drop privileges to open %s: %m", filename);
428 return 0;
429 }
430 f = fopen(filename, "r");
431 err = errno;
432 if (check_prot && seteuid(euid) == -1)
433 fatal("unable to regain privileges");
434 if (f == NULL) {
435 errno = err;
436 if (!must_exist) {
437 if (err != ENOENT && err != ENOTDIR)
438 warn("Warning: can't open options file %s: %m", filename);
439 return 1;
440 }
441 option_error("Can't open options file %s: %m", filename);
442 return 0;
443 }
444
445 oldpriv = privileged_option;
446 privileged_option = priv;
447 oldsource = option_source;
448 option_source = strdup(filename);
449 if (option_source == NULL)
450 option_source = "file";
451 ret = 0;
452 while (getword(f, cmd, &newline, filename)) {
453 opt = find_option(cmd);
454 if (opt == NULL) {
455 option_error("In file %s: unrecognized option '%s'",
456 filename, cmd);
457 goto err;
458 }
459 n = n_arguments(opt);
460 for (i = 0; i < n; ++i) {
461 if (!getword(f, args[i], &newline, filename)) {
462 option_error(
463 "In file %s: too few parameters for option '%s'",
464 filename, cmd);
465 goto err;
466 }
467 argv[i] = args[i];
468 }
469 if (!process_option(opt, cmd, argv))
470 goto err;
471 }
472 ret = 1;
473
474 err:
475 fclose(f);
476 privileged_option = oldpriv;
477 option_source = oldsource;
478 return ret;
479 }
480
481 /*
482 * options_from_user - See if the use has a ~/.ppprc file,
483 * and if so, interpret options from it.
484 */
485 int
options_from_user()486 options_from_user()
487 {
488 char *user, *path, *file;
489 int ret;
490 struct passwd *pw;
491 size_t pl;
492
493 pw = getpwuid(getuid());
494 if (pw == NULL || (user = pw->pw_dir) == NULL || user[0] == 0)
495 return 1;
496 file = _PATH_USEROPT;
497 pl = strlen(user) + strlen(file) + 2;
498 path = malloc(pl);
499 if (path == NULL)
500 novm("init file name");
501 slprintf(path, pl, "%s/%s", user, file);
502 option_priority = OPRIO_CFGFILE;
503 ret = options_from_file(path, 0, 1, privileged);
504 free(path);
505 return ret;
506 }
507
508 /*
509 * options_for_tty - See if an options file exists for the serial
510 * device, and if so, interpret options from it.
511 * We only allow the per-tty options file to override anything from
512 * the command line if it is something that the user can't override
513 * once it has been set by root; this is done by giving configuration
514 * files a lower priority than the command line.
515 */
516 int
options_for_tty()517 options_for_tty()
518 {
519 char *dev, *path, *p;
520 int ret;
521 size_t pl;
522
523 dev = devnam;
524 if ((p = strstr(dev, "/dev/")) != NULL)
525 dev = p + 5;
526 if (dev[0] == 0 || strcmp(dev, "tty") == 0)
527 return 1; /* don't look for /etc/ppp/options.tty */
528 pl = strlen(_PATH_TTYOPT) + strlen(dev) + 1;
529 path = malloc(pl);
530 if (path == NULL)
531 novm("tty init file name");
532 slprintf(path, pl, "%s%s", _PATH_TTYOPT, dev);
533 /* Turn slashes into dots, for Solaris case (e.g. /dev/term/a) */
534 for (p = path + strlen(_PATH_TTYOPT); *p != 0; ++p)
535 if (*p == '/')
536 *p = '.';
537 option_priority = OPRIO_CFGFILE;
538 ret = options_from_file(path, 0, 0, 1);
539 free(path);
540 return ret;
541 }
542
543 /*
544 * options_from_list - process a string of options in a wordlist.
545 */
546 int
options_from_list(w,priv)547 options_from_list(w, priv)
548 struct wordlist *w;
549 int priv;
550 {
551 char *argv[MAXARGS];
552 option_t *opt;
553 int i, n, ret = 0;
554 struct wordlist *w0;
555
556 privileged_option = priv;
557 option_source = "secrets file";
558 option_priority = OPRIO_SECFILE;
559
560 while (w != NULL) {
561 opt = find_option(w->word);
562 if (opt == NULL) {
563 option_error("In secrets file: unrecognized option '%s'",
564 w->word);
565 goto err;
566 }
567 n = n_arguments(opt);
568 w0 = w;
569 for (i = 0; i < n; ++i) {
570 w = w->next;
571 if (w == NULL) {
572 option_error(
573 "In secrets file: too few parameters for option '%s'",
574 w0->word);
575 goto err;
576 }
577 argv[i] = w->word;
578 }
579 if (!process_option(opt, w0->word, argv))
580 goto err;
581 w = w->next;
582 }
583 ret = 1;
584
585 err:
586 return ret;
587 }
588
589 /*
590 * match_option - see if this option matches an option_t structure.
591 */
592 static int
match_option(name,opt,dowild)593 match_option(name, opt, dowild)
594 char *name;
595 option_t *opt;
596 int dowild;
597 {
598 int (*match) __P((char *, char **, int));
599
600 if (dowild != (opt->type == o_wild))
601 return 0;
602 if (!dowild)
603 return strcmp(name, opt->name) == 0;
604 match = (int (*) __P((char *, char **, int))) opt->addr;
605 return (*match)(name, NULL, 0);
606 }
607
608 /*
609 * find_option - scan the option lists for the various protocols
610 * looking for an entry with the given name.
611 * This could be optimized by using a hash table.
612 */
613 static option_t *
find_option(name)614 find_option(name)
615 const char *name;
616 {
617 option_t *opt;
618 struct option_list *list;
619 int i, dowild;
620
621 for (dowild = 0; dowild <= 1; ++dowild) {
622 for (opt = general_options; opt->name != NULL; ++opt)
623 if (match_option(name, opt, dowild))
624 return opt;
625 for (opt = auth_options; opt->name != NULL; ++opt)
626 if (match_option(name, opt, dowild))
627 return opt;
628 for (list = extra_options; list != NULL; list = list->next)
629 for (opt = list->options; opt->name != NULL; ++opt)
630 if (match_option(name, opt, dowild))
631 return opt;
632 for (opt = the_channel->options; opt->name != NULL; ++opt)
633 if (match_option(name, opt, dowild))
634 return opt;
635 for (i = 0; protocols[i] != NULL; ++i)
636 if ((opt = protocols[i]->options) != NULL)
637 for (; opt->name != NULL; ++opt)
638 if (match_option(name, opt, dowild))
639 return opt;
640 }
641 return NULL;
642 }
643
644 /*
645 * process_option - process one new-style option.
646 */
647 static int
process_option(opt,cmd,argv)648 process_option(opt, cmd, argv)
649 option_t *opt;
650 char *cmd;
651 char **argv;
652 {
653 u_int32_t v;
654 int iv, a;
655 char *sv;
656 int (*parser) __P((char **));
657 int (*wildp) __P((char *, char **, int));
658 char *optopt = (opt->type == o_wild)? "": " option";
659 int prio = option_priority;
660 option_t *mainopt = opt;
661
662 current_option = opt->name;
663 if ((opt->flags & OPT_PRIVFIX) && privileged_option)
664 prio += OPRIO_ROOT;
665 while (mainopt->flags & OPT_PRIOSUB)
666 --mainopt;
667 if (mainopt->flags & OPT_PRIO) {
668 if (prio < mainopt->priority) {
669 /* new value doesn't override old */
670 if (prio == OPRIO_CMDLINE && mainopt->priority > OPRIO_ROOT) {
671 option_error("%s%s set in %s cannot be overridden\n",
672 opt->name, optopt, mainopt->source);
673 return 0;
674 }
675 return 1;
676 }
677 if (prio > OPRIO_ROOT && mainopt->priority == OPRIO_CMDLINE)
678 warn("%s%s from %s overrides command line",
679 opt->name, optopt, option_source);
680 }
681
682 if ((opt->flags & OPT_INITONLY) && phase != PHASE_INITIALIZE) {
683 option_error("%s%s cannot be changed after initialization",
684 opt->name, optopt);
685 return 0;
686 }
687 if ((opt->flags & OPT_PRIV) && !privileged_option) {
688 option_error("using the %s%s requires root privilege",
689 opt->name, optopt);
690 return 0;
691 }
692 if ((opt->flags & OPT_ENABLE) && *(bool *)(opt->addr2) == 0) {
693 option_error("%s%s is disabled", opt->name, optopt);
694 return 0;
695 }
696 if ((opt->flags & OPT_DEVEQUIV) && devnam_fixed) {
697 option_error("the %s%s may not be changed in %s",
698 opt->name, optopt, option_source);
699 return 0;
700 }
701
702 switch (opt->type) {
703 case o_bool:
704 v = opt->flags & OPT_VALUE;
705 *(bool *)(opt->addr) = v;
706 if (opt->addr2 && (opt->flags & OPT_A2COPY))
707 *(bool *)(opt->addr2) = v;
708 else if (opt->addr2 && (opt->flags & OPT_A2CLR))
709 *(bool *)(opt->addr2) = 0;
710 else if (opt->addr2 && (opt->flags & OPT_A2CLRB))
711 *(u_char *)(opt->addr2) &= ~v;
712 else if (opt->addr2 && (opt->flags & OPT_A2OR))
713 *(u_char *)(opt->addr2) |= v;
714 break;
715
716 case o_int:
717 iv = 0;
718 if ((opt->flags & OPT_NOARG) == 0) {
719 if (!int_option(*argv, &iv))
720 return 0;
721 if ((((opt->flags & OPT_LLIMIT) && iv < opt->lower_limit)
722 || ((opt->flags & OPT_ULIMIT) && iv > opt->upper_limit))
723 && !((opt->flags & OPT_ZEROOK && iv == 0))) {
724 char *zok = (opt->flags & OPT_ZEROOK)? " zero or": "";
725 switch (opt->flags & OPT_LIMITS) {
726 case OPT_LLIMIT:
727 option_error("%s value must be%s >= %d",
728 opt->name, zok, opt->lower_limit);
729 break;
730 case OPT_ULIMIT:
731 option_error("%s value must be%s <= %d",
732 opt->name, zok, opt->upper_limit);
733 break;
734 case OPT_LIMITS:
735 option_error("%s value must be%s between %d and %d",
736 opt->name, zok, opt->lower_limit, opt->upper_limit);
737 break;
738 }
739 return 0;
740 }
741 }
742 a = opt->flags & OPT_VALUE;
743 if (a >= 128)
744 a -= 256; /* sign extend */
745 iv += a;
746 if (opt->flags & OPT_INC)
747 iv += *(int *)(opt->addr);
748 if ((opt->flags & OPT_NOINCR) && !privileged_option) {
749 int oldv = *(int *)(opt->addr);
750 if ((opt->flags & OPT_ZEROINF) ?
751 (oldv != 0 && (iv == 0 || iv > oldv)) : (iv > oldv)) {
752 option_error("%s value cannot be increased", opt->name);
753 return 0;
754 }
755 }
756 *(int *)(opt->addr) = iv;
757 if (opt->addr2 && (opt->flags & OPT_A2COPY))
758 *(int *)(opt->addr2) = iv;
759 break;
760
761 case o_uint32:
762 if (opt->flags & OPT_NOARG) {
763 v = opt->flags & OPT_VALUE;
764 if (v & 0x80)
765 v |= 0xffffff00U;
766 } else if (!number_option(*argv, &v, 16))
767 return 0;
768 if (opt->flags & OPT_OR)
769 v |= *(u_int32_t *)(opt->addr);
770 *(u_int32_t *)(opt->addr) = v;
771 if (opt->addr2 && (opt->flags & OPT_A2COPY))
772 *(u_int32_t *)(opt->addr2) = v;
773 break;
774
775 case o_string:
776 if (opt->flags & OPT_STATIC) {
777 strlcpy((char *)(opt->addr), *argv, opt->upper_limit);
778 } else {
779 char **optptr = (char **)(opt->addr);
780 sv = strdup(*argv);
781 if (sv == NULL)
782 novm("option argument");
783 if (*optptr)
784 free(*optptr);
785 *optptr = sv;
786 }
787 break;
788
789 case o_special_noarg:
790 case o_special:
791 parser = (int (*) __P((char **))) opt->addr;
792 curopt = opt;
793 if (!(*parser)(argv))
794 return 0;
795 if (opt->flags & OPT_A2LIST) {
796 struct option_value *ovp, *pp;
797
798 ovp = malloc(sizeof(*ovp) + strlen(*argv));
799 if (ovp != 0) {
800 strcpy(ovp->value, *argv);
801 ovp->source = option_source;
802 ovp->next = NULL;
803 if (opt->addr2 == NULL) {
804 opt->addr2 = ovp;
805 } else {
806 for (pp = opt->addr2; pp->next != NULL; pp = pp->next)
807 ;
808 pp->next = ovp;
809 }
810 }
811 }
812 break;
813
814 case o_wild:
815 wildp = (int (*) __P((char *, char **, int))) opt->addr;
816 if (!(*wildp)(cmd, argv, 1))
817 return 0;
818 break;
819 }
820
821 /*
822 * If addr2 wasn't used by any flag (OPT_A2COPY, etc.) but is set,
823 * treat it as a bool and set/clear it based on the OPT_A2CLR bit.
824 */
825 if (opt->addr2 && (opt->flags & (OPT_A2COPY|OPT_ENABLE
826 |OPT_A2PRINTER|OPT_A2STRVAL|OPT_A2LIST|OPT_A2OR)) == 0)
827 *(bool *)(opt->addr2) = !(opt->flags & OPT_A2CLR);
828
829 mainopt->source = option_source;
830 mainopt->priority = prio;
831 mainopt->winner = opt - mainopt;
832
833 return 1;
834 }
835
836 /*
837 * override_value - if the option priorities would permit us to
838 * override the value of option, return 1 and update the priority
839 * and source of the option value. Otherwise returns 0.
840 */
841 int
override_value(option,priority,source)842 override_value(option, priority, source)
843 const char *option;
844 int priority;
845 const char *source;
846 {
847 option_t *opt;
848
849 opt = find_option(option);
850 if (opt == NULL)
851 return 0;
852 while (opt->flags & OPT_PRIOSUB)
853 --opt;
854 if ((opt->flags & OPT_PRIO) && priority < opt->priority)
855 return 0;
856 opt->priority = priority;
857 opt->source = source;
858 opt->winner = -1;
859 return 1;
860 }
861
862 /*
863 * n_arguments - tell how many arguments an option takes
864 */
865 static int
n_arguments(opt)866 n_arguments(opt)
867 option_t *opt;
868 {
869 return (opt->type == o_bool || opt->type == o_special_noarg
870 || (opt->flags & OPT_NOARG))? 0: 1;
871 }
872
873 /*
874 * add_options - add a list of options to the set we grok.
875 */
876 void
add_options(opt)877 add_options(opt)
878 option_t *opt;
879 {
880 struct option_list *list;
881
882 list = malloc(sizeof(*list));
883 if (list == 0)
884 novm("option list entry");
885 list->options = opt;
886 list->next = extra_options;
887 extra_options = list;
888 }
889
890 /*
891 * check_options - check that options are valid and consistent.
892 */
893 void
check_options()894 check_options()
895 {
896 if (logfile_fd >= 0 && logfile_fd != log_to_fd)
897 close(logfile_fd);
898 }
899
900 /*
901 * print_option - print out an option and its value
902 */
903 static void
print_option(opt,mainopt,printer,arg)904 print_option(opt, mainopt, printer, arg)
905 option_t *opt, *mainopt;
906 printer_func printer;
907 void *arg;
908 {
909 int i, v;
910 char *p;
911
912 if (opt->flags & OPT_NOPRINT)
913 return;
914 switch (opt->type) {
915 case o_bool:
916 v = opt->flags & OPT_VALUE;
917 if (*(bool *)opt->addr != v)
918 /* this can happen legitimately, e.g. lock
919 option turned off for default device */
920 break;
921 printer(arg, "%s", opt->name);
922 break;
923 case o_int:
924 v = opt->flags & OPT_VALUE;
925 if (v >= 128)
926 v -= 256;
927 i = *(int *)opt->addr;
928 if (opt->flags & OPT_NOARG) {
929 printer(arg, "%s", opt->name);
930 if (i != v) {
931 if (opt->flags & OPT_INC) {
932 for (; i > v; i -= v)
933 printer(arg, " %s", opt->name);
934 } else
935 printer(arg, " # oops: %d not %d\n",
936 i, v);
937 }
938 } else {
939 printer(arg, "%s %d", opt->name, i);
940 }
941 break;
942 case o_uint32:
943 printer(arg, "%s", opt->name);
944 if ((opt->flags & OPT_NOARG) == 0)
945 printer(arg, " %x", *(u_int32_t *)opt->addr);
946 break;
947
948 case o_string:
949 if (opt->flags & OPT_HIDE) {
950 p = "??????";
951 } else {
952 p = (char *) opt->addr;
953 if ((opt->flags & OPT_STATIC) == 0)
954 p = *(char **)p;
955 }
956 printer(arg, "%s %q", opt->name, p);
957 break;
958
959 case o_special:
960 case o_special_noarg:
961 case o_wild:
962 if (opt->type != o_wild) {
963 printer(arg, "%s", opt->name);
964 if (n_arguments(opt) == 0)
965 break;
966 printer(arg, " ");
967 }
968 if (opt->flags & OPT_A2PRINTER) {
969 void (*oprt) __P((option_t *, printer_func, void *));
970 oprt = (void (*) __P((option_t *, printer_func,
971 void *)))opt->addr2;
972 (*oprt)(opt, printer, arg);
973 } else if (opt->flags & OPT_A2STRVAL) {
974 p = (char *) opt->addr2;
975 if ((opt->flags & OPT_STATIC) == 0)
976 p = *(char **)p;
977 printer("%q", p);
978 } else if (opt->flags & OPT_A2LIST) {
979 struct option_value *ovp;
980
981 ovp = (struct option_value *) opt->addr2;
982 for (;;) {
983 printer(arg, "%q", ovp->value);
984 if ((ovp = ovp->next) == NULL)
985 break;
986 printer(arg, "\t\t# (from %s)\n%s ",
987 ovp->source, opt->name);
988 }
989 } else {
990 printer(arg, "xxx # [don't know how to print value]");
991 }
992 break;
993
994 default:
995 printer(arg, "# %s value (type %d\?\?)", opt->name, opt->type);
996 break;
997 }
998 printer(arg, "\t\t# (from %s)\n", mainopt->source);
999 }
1000
1001 /*
1002 * print_option_list - print out options in effect from an
1003 * array of options.
1004 */
1005 static void
print_option_list(opt,printer,arg)1006 print_option_list(opt, printer, arg)
1007 option_t *opt;
1008 printer_func printer;
1009 void *arg;
1010 {
1011 while (opt->name != NULL) {
1012 if (opt->priority != OPRIO_DEFAULT
1013 && opt->winner != (short int) -1)
1014 print_option(opt + opt->winner, opt, printer, arg);
1015 do {
1016 ++opt;
1017 } while (opt->flags & OPT_PRIOSUB);
1018 }
1019 }
1020
1021 /*
1022 * print_options - print out what options are in effect.
1023 */
1024 void
print_options(printer,arg)1025 print_options(printer, arg)
1026 printer_func printer;
1027 void *arg;
1028 {
1029 struct option_list *list;
1030 int i;
1031
1032 printer(arg, "pppd options in effect:\n");
1033 print_option_list(general_options, printer, arg);
1034 print_option_list(auth_options, printer, arg);
1035 for (list = extra_options; list != NULL; list = list->next)
1036 print_option_list(list->options, printer, arg);
1037 print_option_list(the_channel->options, printer, arg);
1038 for (i = 0; protocols[i] != NULL; ++i)
1039 print_option_list(protocols[i]->options, printer, arg);
1040 }
1041
1042 /*
1043 * usage - print out a message telling how to use the program.
1044 */
1045 static void
usage()1046 usage()
1047 {
1048 if (phase == PHASE_INITIALIZE)
1049 fprintf(stderr, usage_string, VERSION, progname);
1050 }
1051
1052 /*
1053 * showhelp - print out usage message and exit.
1054 */
1055 static int
showhelp(argv)1056 showhelp(argv)
1057 char **argv;
1058 {
1059 if (phase == PHASE_INITIALIZE) {
1060 usage();
1061 exit(0);
1062 }
1063 return 0;
1064 }
1065
1066 /*
1067 * showversion - print out the version number and exit.
1068 */
1069 static int
showversion(argv)1070 showversion(argv)
1071 char **argv;
1072 {
1073 if (phase == PHASE_INITIALIZE) {
1074 fprintf(stderr, "pppd version %s\n", VERSION);
1075 exit(0);
1076 }
1077 return 0;
1078 }
1079
1080 /*
1081 * option_error - print a message about an error in an option.
1082 * The message is logged, and also sent to
1083 * stderr if phase == PHASE_INITIALIZE.
1084 */
1085 void
option_error(char * fmt,...)1086 option_error __V((char *fmt, ...))
1087 {
1088 va_list args;
1089 char buf[1024];
1090
1091 #if defined(__STDC__)
1092 va_start(args, fmt);
1093 #else
1094 char *fmt;
1095 va_start(args);
1096 fmt = va_arg(args, char *);
1097 #endif
1098 vslprintf(buf, sizeof(buf), fmt, args);
1099 va_end(args);
1100 if (phase == PHASE_INITIALIZE)
1101 fprintf(stderr, "%s: %s\n", progname, buf);
1102 syslog(LOG_ERR, "%s", buf);
1103 }
1104
1105 #if 0
1106 /*
1107 * readable - check if a file is readable by the real user.
1108 */
1109 int
1110 readable(fd)
1111 int fd;
1112 {
1113 uid_t uid;
1114 int i;
1115 struct stat sbuf;
1116
1117 uid = getuid();
1118 if (uid == 0)
1119 return 1;
1120 if (fstat(fd, &sbuf) != 0)
1121 return 0;
1122 if (sbuf.st_uid == uid)
1123 return sbuf.st_mode & S_IRUSR;
1124 if (sbuf.st_gid == getgid())
1125 return sbuf.st_mode & S_IRGRP;
1126 for (i = 0; i < ngroups; ++i)
1127 if (sbuf.st_gid == groups[i])
1128 return sbuf.st_mode & S_IRGRP;
1129 return sbuf.st_mode & S_IROTH;
1130 }
1131 #endif
1132
1133 /*
1134 * Read a word from a file.
1135 * Words are delimited by white-space or by quotes (" or ').
1136 * Quotes, white-space and \ may be escaped with \.
1137 * \<newline> is ignored.
1138 */
1139 int
getword(f,word,newlinep,filename)1140 getword(f, word, newlinep, filename)
1141 FILE *f;
1142 char *word;
1143 int *newlinep;
1144 char *filename;
1145 {
1146 int c, len, escape;
1147 int quoted, comment;
1148 int value, digit, got, n;
1149
1150 #define isoctal(c) ((c) >= '0' && (c) < '8')
1151
1152 *newlinep = 0;
1153 len = 0;
1154 escape = 0;
1155 comment = 0;
1156 quoted = 0;
1157
1158 /*
1159 * First skip white-space and comments.
1160 */
1161 for (;;) {
1162 c = getc(f);
1163 if (c == EOF)
1164 break;
1165
1166 /*
1167 * A newline means the end of a comment; backslash-newline
1168 * is ignored. Note that we cannot have escape && comment.
1169 */
1170 if (c == '\n') {
1171 if (!escape) {
1172 *newlinep = 1;
1173 comment = 0;
1174 } else
1175 escape = 0;
1176 continue;
1177 }
1178
1179 /*
1180 * Ignore characters other than newline in a comment.
1181 */
1182 if (comment)
1183 continue;
1184
1185 /*
1186 * If this character is escaped, we have a word start.
1187 */
1188 if (escape)
1189 break;
1190
1191 /*
1192 * If this is the escape character, look at the next character.
1193 */
1194 if (c == '\\') {
1195 escape = 1;
1196 continue;
1197 }
1198
1199 /*
1200 * If this is the start of a comment, ignore the rest of the line.
1201 */
1202 if (c == '#') {
1203 comment = 1;
1204 continue;
1205 }
1206
1207 /*
1208 * A non-whitespace character is the start of a word.
1209 */
1210 if (!isspace(c))
1211 break;
1212 }
1213
1214 /*
1215 * Process characters until the end of the word.
1216 */
1217 while (c != EOF) {
1218 if (escape) {
1219 /*
1220 * This character is escaped: backslash-newline is ignored,
1221 * various other characters indicate particular values
1222 * as for C backslash-escapes.
1223 */
1224 escape = 0;
1225 if (c == '\n') {
1226 c = getc(f);
1227 continue;
1228 }
1229
1230 got = 0;
1231 switch (c) {
1232 case 'a':
1233 value = '\a';
1234 break;
1235 case 'b':
1236 value = '\b';
1237 break;
1238 case 'f':
1239 value = '\f';
1240 break;
1241 case 'n':
1242 value = '\n';
1243 break;
1244 case 'r':
1245 value = '\r';
1246 break;
1247 case 's':
1248 value = ' ';
1249 break;
1250 case 't':
1251 value = '\t';
1252 break;
1253
1254 default:
1255 if (isoctal(c)) {
1256 /*
1257 * \ddd octal sequence
1258 */
1259 value = 0;
1260 for (n = 0; n < 3 && isoctal(c); ++n) {
1261 value = (value << 3) + (c & 07);
1262 c = getc(f);
1263 }
1264 got = 1;
1265 break;
1266 }
1267
1268 if (c == 'x') {
1269 /*
1270 * \x<hex_string> sequence
1271 */
1272 value = 0;
1273 c = getc(f);
1274 for (n = 0; n < 2 && isxdigit(c); ++n) {
1275 digit = toupper(c) - '0';
1276 if (digit > 10)
1277 digit += '0' + 10 - 'A';
1278 value = (value << 4) + digit;
1279 c = getc (f);
1280 }
1281 got = 1;
1282 break;
1283 }
1284
1285 /*
1286 * Otherwise the character stands for itself.
1287 */
1288 value = c;
1289 break;
1290 }
1291
1292 /*
1293 * Store the resulting character for the escape sequence.
1294 */
1295 if (len < MAXWORDLEN) {
1296 word[len] = value;
1297 ++len;
1298 }
1299
1300 if (!got)
1301 c = getc(f);
1302 continue;
1303 }
1304
1305 /*
1306 * Backslash starts a new escape sequence.
1307 */
1308 if (c == '\\') {
1309 escape = 1;
1310 c = getc(f);
1311 continue;
1312 }
1313
1314 /*
1315 * Not escaped: check for the start or end of a quoted
1316 * section and see if we've reached the end of the word.
1317 */
1318 if (quoted) {
1319 if (c == quoted) {
1320 quoted = 0;
1321 c = getc(f);
1322 continue;
1323 }
1324 } else if (c == '"' || c == '\'') {
1325 quoted = c;
1326 c = getc(f);
1327 continue;
1328 } else if (isspace(c) || c == '#') {
1329 ungetc (c, f);
1330 break;
1331 }
1332
1333 /*
1334 * An ordinary character: store it in the word and get another.
1335 */
1336 if (len < MAXWORDLEN) {
1337 word[len] = c;
1338 ++len;
1339 }
1340
1341 c = getc(f);
1342 }
1343
1344 /*
1345 * End of the word: check for errors.
1346 */
1347 if (c == EOF) {
1348 if (ferror(f)) {
1349 if (errno == 0)
1350 errno = EIO;
1351 option_error("Error reading %s: %m", filename);
1352 die(1);
1353 }
1354 /*
1355 * If len is zero, then we didn't find a word before the
1356 * end of the file.
1357 */
1358 if (len == 0)
1359 return 0;
1360 if (quoted)
1361 option_error("warning: quoted word runs to end of file (%.20s...)",
1362 filename, word);
1363 }
1364
1365 /*
1366 * Warn if the word was too long, and append a terminating null.
1367 */
1368 if (len >= MAXWORDLEN) {
1369 option_error("warning: word in file %s too long (%.20s...)",
1370 filename, word);
1371 len = MAXWORDLEN - 1;
1372 }
1373 word[len] = 0;
1374
1375 return 1;
1376
1377 #undef isoctal
1378
1379 }
1380
1381 /*
1382 * number_option - parse an unsigned numeric parameter for an option.
1383 */
1384 static int
number_option(str,valp,base)1385 number_option(str, valp, base)
1386 char *str;
1387 u_int32_t *valp;
1388 int base;
1389 {
1390 char *ptr;
1391
1392 *valp = strtoul(str, &ptr, base);
1393 if (ptr == str) {
1394 option_error("invalid numeric parameter '%s' for %s option",
1395 str, current_option);
1396 return 0;
1397 }
1398 return 1;
1399 }
1400
1401
1402 /*
1403 * int_option - like number_option, but valp is int *,
1404 * the base is assumed to be 0, and *valp is not changed
1405 * if there is an error.
1406 */
1407 int
int_option(str,valp)1408 int_option(str, valp)
1409 char *str;
1410 int *valp;
1411 {
1412 u_int32_t v;
1413
1414 if (!number_option(str, &v, 0))
1415 return 0;
1416 *valp = (int) v;
1417 return 1;
1418 }
1419
1420
1421 /*
1422 * The following procedures parse options.
1423 */
1424
1425 /*
1426 * readfile - take commands from a file.
1427 */
1428 static int
readfile(argv)1429 readfile(argv)
1430 char **argv;
1431 {
1432 return options_from_file(*argv, 1, 1, privileged_option);
1433 }
1434
1435 /*
1436 * callfile - take commands from /etc/ppp/peers/<name>.
1437 * Name may not contain /../, start with / or ../, or end in /..
1438 */
1439 static int
callfile(argv)1440 callfile(argv)
1441 char **argv;
1442 {
1443 char *fname, *arg, *p;
1444 int l, ok;
1445
1446 arg = *argv;
1447 ok = 1;
1448 if (arg[0] == '/' || arg[0] == 0)
1449 ok = 0;
1450 else {
1451 for (p = arg; *p != 0; ) {
1452 if (p[0] == '.' && p[1] == '.' && (p[2] == '/' || p[2] == 0)) {
1453 ok = 0;
1454 break;
1455 }
1456 while (*p != '/' && *p != 0)
1457 ++p;
1458 if (*p == '/')
1459 ++p;
1460 }
1461 }
1462 if (!ok) {
1463 option_error("call option value may not contain .. or start with /");
1464 return 0;
1465 }
1466
1467 l = strlen(arg) + strlen(_PATH_PEERFILES) + 1;
1468 if ((fname = (char *) malloc(l)) == NULL)
1469 novm("call file name");
1470 slprintf(fname, l, "%s%s", _PATH_PEERFILES, arg);
1471
1472 ok = options_from_file(fname, 1, 1, 1);
1473
1474 free(fname);
1475 return ok;
1476 }
1477
1478 #ifdef PPP_FILTER
1479 /*
1480 * setpassfilter - Set the pass filter for packets
1481 */
1482 static int
setpassfilter(argv)1483 setpassfilter(argv)
1484 char **argv;
1485 {
1486 pcap_t *pc;
1487 int ret = 1;
1488
1489 pc = pcap_open_dead(DLT_PPP_PPPD, 65535);
1490 if (pcap_compile(pc, &pass_filter, *argv, 1, netmask) == -1) {
1491 option_error("error in pass-filter expression: %s\n",
1492 pcap_geterr(pc));
1493 ret = 0;
1494 }
1495 pcap_close(pc);
1496
1497 return ret;
1498 }
1499
1500 /*
1501 * setactivefilter - Set the active filter for packets
1502 */
1503 static int
setactivefilter(argv)1504 setactivefilter(argv)
1505 char **argv;
1506 {
1507 pcap_t *pc;
1508 int ret = 1;
1509
1510 pc = pcap_open_dead(DLT_PPP_PPPD, 65535);
1511 if (pcap_compile(pc, &active_filter, *argv, 1, netmask) == -1) {
1512 option_error("error in active-filter expression: %s\n",
1513 pcap_geterr(pc));
1514 ret = 0;
1515 }
1516 pcap_close(pc);
1517
1518 return ret;
1519 }
1520 #endif
1521
1522 /*
1523 * setdomain - Set domain name to append to hostname
1524 */
1525 static int
setdomain(argv)1526 setdomain(argv)
1527 char **argv;
1528 {
1529 gethostname(hostname, MAXNAMELEN);
1530 if (**argv != 0) {
1531 if (**argv != '.')
1532 strncat(hostname, ".", MAXNAMELEN - strlen(hostname));
1533 domain = hostname + strlen(hostname);
1534 strncat(hostname, *argv, MAXNAMELEN - strlen(hostname));
1535 }
1536 hostname[MAXNAMELEN-1] = 0;
1537 return (1);
1538 }
1539
1540 static int
setlogfile(argv)1541 setlogfile(argv)
1542 char **argv;
1543 {
1544 int fd, err;
1545 uid_t euid;
1546
1547 euid = geteuid();
1548 if (!privileged_option && seteuid(getuid()) == -1) {
1549 option_error("unable to drop permissions to open %s: %m", *argv);
1550 return 0;
1551 }
1552 fd = open(*argv, O_WRONLY | O_APPEND | O_CREAT | O_EXCL, 0644);
1553 if (fd < 0 && errno == EEXIST)
1554 fd = open(*argv, O_WRONLY | O_APPEND);
1555 err = errno;
1556 if (!privileged_option && seteuid(euid) == -1)
1557 fatal("unable to regain privileges: %m");
1558 if (fd < 0) {
1559 errno = err;
1560 option_error("Can't open log file %s: %m", *argv);
1561 return 0;
1562 }
1563 strlcpy(logfile_name, *argv, sizeof(logfile_name));
1564 if (logfile_fd >= 0)
1565 close(logfile_fd);
1566 logfile_fd = fd;
1567 log_to_fd = fd;
1568 log_default = 0;
1569 return 1;
1570 }
1571
1572 #ifdef MAXOCTETS
1573 static int
setmodir(argv)1574 setmodir(argv)
1575 char **argv;
1576 {
1577 if(*argv == NULL)
1578 return 0;
1579 if(!strcmp(*argv,"in")) {
1580 maxoctets_dir = PPP_OCTETS_DIRECTION_IN;
1581 } else if (!strcmp(*argv,"out")) {
1582 maxoctets_dir = PPP_OCTETS_DIRECTION_OUT;
1583 } else if (!strcmp(*argv,"max")) {
1584 maxoctets_dir = PPP_OCTETS_DIRECTION_MAXOVERAL;
1585 } else {
1586 maxoctets_dir = PPP_OCTETS_DIRECTION_SUM;
1587 }
1588 return 1;
1589 }
1590 #endif
1591
1592 #ifdef PLUGIN
1593 static int
loadplugin(argv)1594 loadplugin(argv)
1595 char **argv;
1596 {
1597 char *arg = *argv;
1598 void *handle;
1599 const char *err;
1600 void (*init) __P((void));
1601 char *path = arg;
1602 const char *vers;
1603
1604 if (strchr(arg, '/') == 0) {
1605 const char *base = _PATH_PLUGIN;
1606 int l = strlen(base) + strlen(arg) + 2;
1607 path = malloc(l);
1608 if (path == 0)
1609 novm("plugin file path");
1610 strlcpy(path, base, l);
1611 strlcat(path, "/", l);
1612 strlcat(path, arg, l);
1613 }
1614 handle = dlopen(path, RTLD_GLOBAL | RTLD_NOW);
1615 if (handle == 0) {
1616 err = dlerror();
1617 if (err != 0)
1618 option_error("%s", err);
1619 option_error("Couldn't load plugin %s", arg);
1620 goto err;
1621 }
1622 init = (void (*)(void))dlsym(handle, "plugin_init");
1623 if (init == 0) {
1624 option_error("%s has no initialization entry point", arg);
1625 goto errclose;
1626 }
1627 vers = (const char *) dlsym(handle, "pppd_version");
1628 if (vers == 0) {
1629 warn("Warning: plugin %s has no version information", arg);
1630 } else if (strcmp(vers, VERSION) != 0) {
1631 option_error("Plugin %s is for pppd version %s, this is %s",
1632 arg, vers, VERSION);
1633 goto errclose;
1634 }
1635 info("Plugin %s loaded.", arg);
1636 (*init)();
1637 return 1;
1638
1639 errclose:
1640 dlclose(handle);
1641 err:
1642 if (path != arg)
1643 free(path);
1644 return 0;
1645 }
1646 #endif /* PLUGIN */
1647
1648 /*
1649 * Set an environment variable specified by the user.
1650 */
1651 static int
user_setenv(argv)1652 user_setenv(argv)
1653 char **argv;
1654 {
1655 char *arg = argv[0];
1656 char *eqp;
1657 struct userenv *uep, **insp;
1658
1659 if ((eqp = strchr(arg, '=')) == NULL) {
1660 option_error("missing = in name=value: %s", arg);
1661 return 0;
1662 }
1663 if (eqp == arg) {
1664 option_error("missing variable name: %s", arg);
1665 return 0;
1666 }
1667 for (uep = userenv_list; uep != NULL; uep = uep->ue_next) {
1668 int nlen = strlen(uep->ue_name);
1669 if (nlen == (eqp - arg) &&
1670 strncmp(arg, uep->ue_name, nlen) == 0)
1671 break;
1672 }
1673 /* Ignore attempts by unprivileged users to override privileged sources */
1674 if (uep != NULL && !privileged_option && uep->ue_priv)
1675 return 1;
1676 /* The name never changes, so allocate it with the structure */
1677 if (uep == NULL) {
1678 uep = malloc(sizeof (*uep) + (eqp-arg));
1679 strncpy(uep->ue_name, arg, eqp-arg);
1680 uep->ue_name[eqp-arg] = '\0';
1681 uep->ue_next = NULL;
1682 insp = &userenv_list;
1683 while (*insp != NULL)
1684 insp = &(*insp)->ue_next;
1685 *insp = uep;
1686 } else {
1687 struct userenv *uep2;
1688 for (uep2 = userenv_list; uep2 != NULL; uep2 = uep2->ue_next) {
1689 if (uep2 != uep && !uep2->ue_isset)
1690 break;
1691 }
1692 if (uep2 == NULL && !uep->ue_isset)
1693 find_option("unset")->flags |= OPT_NOPRINT;
1694 free(uep->ue_value);
1695 }
1696 uep->ue_isset = 1;
1697 uep->ue_priv = privileged_option;
1698 uep->ue_source = option_source;
1699 uep->ue_value = strdup(eqp + 1);
1700 curopt->flags &= ~OPT_NOPRINT;
1701 return 1;
1702 }
1703
1704 static void
user_setprint(opt,printer,arg)1705 user_setprint(opt, printer, arg)
1706 option_t *opt;
1707 printer_func printer;
1708 void *arg;
1709 {
1710 struct userenv *uep, *uepnext;
1711
1712 uepnext = userenv_list;
1713 while (uepnext != NULL && !uepnext->ue_isset)
1714 uepnext = uepnext->ue_next;
1715 while ((uep = uepnext) != NULL) {
1716 uepnext = uep->ue_next;
1717 while (uepnext != NULL && !uepnext->ue_isset)
1718 uepnext = uepnext->ue_next;
1719 (*printer)(arg, "%s=%s", uep->ue_name, uep->ue_value);
1720 if (uepnext != NULL)
1721 (*printer)(arg, "\t\t# (from %s)\n%s ", uep->ue_source, opt->name);
1722 else
1723 opt->source = uep->ue_source;
1724 }
1725 }
1726
1727 static int
user_unsetenv(argv)1728 user_unsetenv(argv)
1729 char **argv;
1730 {
1731 struct userenv *uep, **insp;
1732 char *arg = argv[0];
1733
1734 if (strchr(arg, '=') != NULL) {
1735 option_error("unexpected = in name: %s", arg);
1736 return 0;
1737 }
1738 if (arg == '\0') {
1739 option_error("missing variable name for unset");
1740 return 0;
1741 }
1742 for (uep = userenv_list; uep != NULL; uep = uep->ue_next) {
1743 if (strcmp(arg, uep->ue_name) == 0)
1744 break;
1745 }
1746 /* Ignore attempts by unprivileged users to override privileged sources */
1747 if (uep != NULL && !privileged_option && uep->ue_priv)
1748 return 1;
1749 /* The name never changes, so allocate it with the structure */
1750 if (uep == NULL) {
1751 uep = malloc(sizeof (*uep) + strlen(arg));
1752 strcpy(uep->ue_name, arg);
1753 uep->ue_next = NULL;
1754 insp = &userenv_list;
1755 while (*insp != NULL)
1756 insp = &(*insp)->ue_next;
1757 *insp = uep;
1758 } else {
1759 struct userenv *uep2;
1760 for (uep2 = userenv_list; uep2 != NULL; uep2 = uep2->ue_next) {
1761 if (uep2 != uep && uep2->ue_isset)
1762 break;
1763 }
1764 if (uep2 == NULL && uep->ue_isset)
1765 find_option("set")->flags |= OPT_NOPRINT;
1766 free(uep->ue_value);
1767 }
1768 uep->ue_isset = 0;
1769 uep->ue_priv = privileged_option;
1770 uep->ue_source = option_source;
1771 uep->ue_value = NULL;
1772 curopt->flags &= ~OPT_NOPRINT;
1773 return 1;
1774 }
1775
1776 static void
user_unsetprint(opt,printer,arg)1777 user_unsetprint(opt, printer, arg)
1778 option_t *opt;
1779 printer_func printer;
1780 void *arg;
1781 {
1782 struct userenv *uep, *uepnext;
1783
1784 uepnext = userenv_list;
1785 while (uepnext != NULL && uepnext->ue_isset)
1786 uepnext = uepnext->ue_next;
1787 while ((uep = uepnext) != NULL) {
1788 uepnext = uep->ue_next;
1789 while (uepnext != NULL && uepnext->ue_isset)
1790 uepnext = uepnext->ue_next;
1791 (*printer)(arg, "%s", uep->ue_name);
1792 if (uepnext != NULL)
1793 (*printer)(arg, "\t\t# (from %s)\n%s ", uep->ue_source, opt->name);
1794 else
1795 opt->source = uep->ue_source;
1796 }
1797 }
1798