2 * options.c - handles option processing for PPP.
4 * Copyright (c) 1984-2000 Carnegie Mellon University. All rights reserved.
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7 * modification, are permitted provided that the following conditions
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20 * prior written permission. For permission or any legal
21 * details, please contact
22 * Office of Technology Transfer
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57 #include <sys/param.h>
59 #ifdef PPP_WITH_PLUGINS
63 #ifdef PPP_WITH_FILTER
66 * There have been 3 or 4 different names for this in libpcap CVS, but
67 * this seems to be what they have settled on...
68 * For older versions of libpcap, use DLT_PPP - but that means
69 * we lose the inbound and outbound qualifiers.
72 #ifdef DLT_PPP_WITHDIRECTION
73 #define DLT_PPP_PPPD DLT_PPP_WITHDIRECTION
75 #define DLT_PPP_PPPD DLT_PPP
78 #endif /* PPP_WITH_FILTER */
80 #include "pppd-private.h"
83 #include "pathnames.h"
85 #if defined(ultrix) || defined(NeXT)
91 struct option_value *next;
97 * Option variables and default values.
99 int debug = 0; /* Debug flag */
100 int kdebugflag = 0; /* Tell kernel to print debug messages */
101 int default_device = 1; /* Using /dev/tty or equivalent */
102 bool nodetach = 0; /* Don't detach from controlling tty */
103 bool updetach = 0; /* Detach once link is up */
104 bool master_detach; /* Detach when we're (only) multilink master */
106 bool up_sdnotify = 0; /* Notify systemd once link is up */
108 int maxconnect = 0; /* Maximum connect time */
109 char user[MAXNAMELEN]; /* Username for PAP */
110 char passwd[MAXSECRETLEN]; /* Password for PAP */
111 bool persist = 0; /* Reopen link after it goes down */
112 char our_name[MAXNAMELEN]; /* Our name for authentication purposes */
113 bool demand = 0; /* do dial-on-demand */
114 int idle_time_limit = 0; /* Disconnect if idle for this many seconds */
115 int holdoff = 30; /* # seconds to pause before reconnecting */
116 bool holdoff_specified; /* true if a holdoff value has been given */
117 int log_to_fd = 1; /* send log messages to this fd too */
118 bool log_default = 1; /* log_to_fd is default (stdout) */
119 int maxfail = 10; /* max # of unsuccessful connection attempts */
120 char linkname[MAXPATHLEN]; /* logical name for link */
121 bool tune_kernel; /* may alter kernel settings */
122 int connect_delay = 1000; /* wait this many ms after connect script */
123 int req_unit = -1; /* requested interface unit */
124 char path_ipup[MAXPATHLEN]; /* pathname of ip-up script */
125 char path_ipdown[MAXPATHLEN];/* pathname of ip-down script */
126 char req_ifname[IFNAMSIZ]; /* requested interface name */
127 bool multilink = 0; /* Enable multilink operation */
128 char *bundle_name = NULL; /* bundle name for multilink */
129 bool dump_options; /* print out option values */
130 bool show_options; /* print all supported options and exit */
131 bool dryrun; /* print out option values and exit */
132 char *domain; /* domain name set by domain option */
133 int child_wait = 5; /* # seconds to wait for children at exit */
134 struct userenv *userenv_list; /* user environment variables */
135 int dfl_route_metric = -1; /* metric of the default route to set over the PPP link */
137 #ifdef PPP_WITH_IPV6CP
138 char path_ipv6up[MAXPATHLEN]; /* pathname of ipv6-up script */
139 char path_ipv6down[MAXPATHLEN]; /* pathname of ipv6-down script */
142 unsigned int maxoctets = 0; /* default - no limit */
143 session_limit_dir_t maxoctets_dir = PPP_OCTETS_DIRECTION_SUM; /* default - sum of traffic */
144 int maxoctets_timeout = 1; /* default 1 second */
147 extern struct option auth_options[];
148 extern struct stat devstat;
150 #ifdef PPP_WITH_FILTER
151 struct bpf_program pass_filter;/* Filter program for packets to pass */
152 struct bpf_program active_filter; /* Filter program for link-active pkts */
155 static struct option *curopt; /* pointer to option being processed */
156 char *current_option; /* the name of the option being parsed */
157 int privileged_option; /* set iff the current option came from root */
158 char *option_source; /* string saying where the option came from */
159 int option_priority = OPRIO_CFGFILE; /* priority of the current options */
160 bool devnam_fixed; /* can no longer change device name */
162 static int logfile_fd = -1; /* fd opened for log file */
163 static char logfile_name[MAXPATHLEN]; /* name of log file */
165 static bool noipx_opt; /* dummy for noipx option */
170 static int setdomain(char **);
171 static int readfile(char **);
172 static int callfile(char **);
173 static int showversion(char **);
174 static int showhelp(char **);
175 static void usage(void);
176 static int setlogfile(char **);
177 #ifdef PPP_WITH_PLUGINS
178 static int loadplugin(char **);
181 #ifdef PPP_WITH_FILTER
182 static int setpassfilter(char **);
183 static int setactivefilter(char **);
186 static int setmodir(char **);
188 static int user_setenv(char **);
189 static void user_setprint(struct option *, printer_func, void *);
190 static int user_unsetenv(char **);
191 static void user_unsetprint(struct option *, printer_func, void *);
193 static struct option *find_option(char *name);
194 static int process_option(struct option *, char *, char **);
195 static int n_arguments(struct option *);
196 static int number_option(char *, u_int32_t *, int);
199 * Structure to store extra lists of options.
202 struct option *options;
203 struct option_list *next;
206 static struct option_list *extra_options = NULL;
211 struct option general_options[] = {
212 { "debug", o_int, &debug,
213 "Increase debugging level", OPT_INC | OPT_NOARG | 1 },
214 { "-d", o_int, &debug,
215 "Increase debugging level",
216 OPT_ALIAS | OPT_INC | OPT_NOARG | 1 },
218 { "kdebug", o_int, &kdebugflag,
219 "Set kernel driver debug level", OPT_PRIO },
221 { "nodetach", o_bool, &nodetach,
222 "Don't detach from controlling tty", OPT_PRIO | 1 },
223 { "-detach", o_bool, &nodetach,
224 "Don't detach from controlling tty", OPT_ALIAS | OPT_PRIOSUB | 1 },
226 { "up_sdnotify", o_bool, &up_sdnotify,
227 "Notify systemd once link is up (implies nodetach)",
228 OPT_PRIOSUB | OPT_A2COPY | 1, &nodetach },
230 { "updetach", o_bool, &updetach,
231 "Detach from controlling tty once link is up",
232 OPT_PRIOSUB | OPT_A2CLR | 1, &nodetach },
234 { "master_detach", o_bool, &master_detach,
235 "Detach when we're multilink master but have no link", 1 },
237 { "holdoff", o_int, &holdoff,
238 "Set time in seconds before retrying connection",
239 OPT_PRIO, &holdoff_specified },
241 { "idle", o_int, &idle_time_limit,
242 "Set time in seconds before disconnecting idle link", OPT_PRIO },
244 { "maxconnect", o_int, &maxconnect,
245 "Set connection time limit",
246 OPT_PRIO | OPT_LLIMIT | OPT_NOINCR | OPT_ZEROINF },
248 { "domain", o_special, (void *)setdomain,
249 "Add given domain name to hostname",
250 OPT_PRIO | OPT_PRIV | OPT_A2STRVAL, &domain },
252 { "file", o_special, (void *)readfile,
253 "Take options from a file", OPT_NOPRINT },
254 { "call", o_special, (void *)callfile,
255 "Take options from a privileged file", OPT_NOPRINT },
257 { "persist", o_bool, &persist,
258 "Keep on reopening connection after close", OPT_PRIO | 1 },
259 { "nopersist", o_bool, &persist,
260 "Turn off persist option", OPT_PRIOSUB },
262 { "demand", o_bool, &demand,
263 "Dial on demand", OPT_INITONLY | 1, &persist },
265 { "--version", o_special_noarg, (void *)showversion,
266 "Show version number" },
267 { "-v", o_special_noarg, (void *)showversion,
268 "Show version number" },
269 { "show-options", o_bool, &show_options,
270 "Show all options and exit", 1 },
271 { "--help", o_special_noarg, (void *)showhelp,
272 "Show brief listing of options" },
273 { "-h", o_special_noarg, (void *)showhelp,
274 "Show brief listing of options", OPT_ALIAS },
276 { "logfile", o_special, (void *)setlogfile,
277 "Append log messages to this file",
278 OPT_PRIO | OPT_A2STRVAL | OPT_STATIC, &logfile_name },
279 { "logfd", o_int, &log_to_fd,
280 "Send log messages to this file descriptor",
281 OPT_PRIOSUB | OPT_A2CLR, &log_default },
282 { "nolog", o_int, &log_to_fd,
283 "Don't send log messages to any file",
284 OPT_PRIOSUB | OPT_NOARG | OPT_VAL(-1) },
285 { "nologfd", o_int, &log_to_fd,
286 "Don't send log messages to any file descriptor",
287 OPT_PRIOSUB | OPT_ALIAS | OPT_NOARG | OPT_VAL(-1) },
289 { "linkname", o_string, linkname,
290 "Set logical name for link",
291 OPT_PRIO | OPT_PRIV | OPT_STATIC, NULL, MAXPATHLEN },
293 { "maxfail", o_int, &maxfail,
294 "Maximum number of unsuccessful connection attempts to allow",
297 { "ktune", o_bool, &tune_kernel,
298 "Alter kernel settings as necessary", OPT_PRIO | 1 },
299 { "noktune", o_bool, &tune_kernel,
300 "Don't alter kernel settings", OPT_PRIOSUB },
302 { "connect-delay", o_int, &connect_delay,
303 "Maximum time (in ms) to wait after connect script finishes",
306 { "unit", o_int, &req_unit,
307 "PPP interface unit number to use if possible",
308 OPT_PRIO | OPT_LLIMIT, 0, 0 },
310 { "ifname", o_string, req_ifname,
311 "Set PPP interface name",
312 OPT_PRIO | OPT_PRIV | OPT_STATIC, NULL, IFNAMSIZ },
314 { "dump", o_bool, &dump_options,
315 "Print out option values after parsing all options", 1 },
316 { "dryrun", o_bool, &dryrun,
317 "Stop after parsing, printing, and checking options", 1 },
319 { "child-timeout", o_int, &child_wait,
320 "Number of seconds to wait for child processes at exit",
323 { "set", o_special, (void *)user_setenv,
324 "Set user environment variable",
325 OPT_A2PRINTER | OPT_NOPRINT, (void *)user_setprint },
326 { "unset", o_special, (void *)user_unsetenv,
327 "Unset user environment variable",
328 OPT_A2PRINTER | OPT_NOPRINT, (void *)user_unsetprint },
330 { "defaultroute-metric", o_int, &dfl_route_metric,
331 "Metric to use for the default route (Linux only; -1 for default behavior)",
332 OPT_PRIV|OPT_LLIMIT|OPT_INITONLY, NULL, 0, -1 },
334 { "ip-up-script", o_string, path_ipup,
335 "Set pathname of ip-up script",
336 OPT_PRIV|OPT_STATIC, NULL, MAXPATHLEN },
337 { "ip-down-script", o_string, path_ipdown,
338 "Set pathname of ip-down script",
339 OPT_PRIV|OPT_STATIC, NULL, MAXPATHLEN },
341 #ifdef PPP_WITH_IPV6CP
342 { "ipv6-up-script", o_string, path_ipv6up,
343 "Set pathname of ipv6-up script",
344 OPT_PRIV|OPT_STATIC, NULL, MAXPATHLEN },
345 { "ipv6-down-script", o_string, path_ipv6down,
346 "Set pathname of ipv6-down script",
347 OPT_PRIV|OPT_STATIC, NULL, MAXPATHLEN },
350 #ifdef PPP_WITH_MULTILINK
351 { "multilink", o_bool, &multilink,
352 "Enable multilink operation", OPT_PRIO | 1 },
353 { "mp", o_bool, &multilink,
354 "Enable multilink operation", OPT_PRIOSUB | OPT_ALIAS | 1 },
355 { "nomultilink", o_bool, &multilink,
356 "Disable multilink operation", OPT_PRIOSUB | 0 },
357 { "nomp", o_bool, &multilink,
358 "Disable multilink operation", OPT_PRIOSUB | OPT_ALIAS | 0 },
360 { "bundle", o_string, &bundle_name,
361 "Bundle name for multilink", OPT_PRIO },
362 #endif /* PPP_WITH_MULTILINK */
364 #ifdef PPP_WITH_PLUGINS
365 { "plugin", o_special, (void *)loadplugin,
366 "Load a plug-in module into pppd", OPT_PRIV | OPT_A2LIST },
369 #ifdef PPP_WITH_FILTER
370 { "pass-filter", o_special, setpassfilter,
371 "set filter for packets to pass", OPT_PRIO },
373 { "active-filter", o_special, setactivefilter,
374 "set filter for active pkts", OPT_PRIO },
377 { "maxoctets", o_int, &maxoctets,
378 "Set connection traffic limit",
379 OPT_PRIO | OPT_LLIMIT | OPT_NOINCR | OPT_ZEROINF },
380 { "mo", o_int, &maxoctets,
381 "Set connection traffic limit",
382 OPT_ALIAS | OPT_PRIO | OPT_LLIMIT | OPT_NOINCR | OPT_ZEROINF },
383 { "mo-direction", o_special, setmodir,
384 "Set direction for limit traffic (sum,in,out,max)" },
385 { "mo-timeout", o_int, &maxoctets_timeout,
386 "Check for traffic limit every N seconds", OPT_PRIO | OPT_LLIMIT | 1 },
388 /* Dummy option, does nothing */
389 { "noipx", o_bool, &noipx_opt, NULL, OPT_NOPRINT | 1 },
394 #ifndef IMPLEMENTATION
395 #define IMPLEMENTATION ""
399 ppp_get_max_idle_time()
401 return idle_time_limit;
405 ppp_set_max_idle_time(unsigned int max)
407 idle_time_limit = max;
411 ppp_get_max_connect_time()
417 ppp_set_max_connect_time(unsigned int max)
423 ppp_set_session_limit(unsigned int octets)
429 ppp_set_session_limit_dir(unsigned int dir)
432 dir = PPP_OCTETS_DIRECTION_SUM;
433 maxoctets_dir = (session_limit_dir_t) dir;
443 ppp_get_path(ppp_path_t type, char *buf, size_t bufsz)
447 if (buf && bufsz > 0) {
450 path = PPP_PATH_VARLOG;
452 case PPP_DIR_RUNTIME:
453 path = PPP_PATH_VARRUN;
455 #ifdef PPP_WITH_PLUGINS
457 path = PPP_PATH_PLUGIN;
461 path = PPP_PATH_CONFDIR;
464 return strlcpy(buf, path, bufsz);
470 ppp_get_filepath(ppp_path_t type, const char *name, char *buf, size_t bufsz)
474 if (buf && bufsz > 0) {
477 path = PPP_PATH_VARLOG;
479 case PPP_DIR_RUNTIME:
480 path = PPP_PATH_VARRUN;
482 #ifdef PPP_WITH_PLUGINS
484 path = PPP_PATH_PLUGIN;
488 path = PPP_PATH_CONFDIR;
491 return slprintf(buf, bufsz, "%s/%s", path, name);
502 * parse_args - parse a string of arguments from the command line.
505 parse_args(int argc, char **argv)
511 privileged_option = privileged;
512 option_source = "command line";
513 option_priority = OPRIO_CMDLINE;
517 opt = find_option(arg);
519 ppp_option_error("unrecognized option '%s'", arg);
523 n = n_arguments(opt);
525 ppp_option_error("too few parameters for option %s", arg);
528 if (!process_option(opt, arg, argv))
537 * options_from_file - Read a string of options from a file,
538 * and interpret them.
541 ppp_options_from_file(char *filename, int must_exist, int check_prot, int priv)
544 int i, newline, ret, err;
550 char args[MAXARGS][MAXWORDLEN];
551 char cmd[MAXWORDLEN];
554 if (check_prot && seteuid(getuid()) == -1) {
555 ppp_option_error("unable to drop privileges to open %s: %m", filename);
558 f = fopen(filename, "r");
560 if (check_prot && seteuid(euid) == -1)
561 fatal("unable to regain privileges");
565 if (err != ENOENT && err != ENOTDIR)
566 warn("Warning: can't open options file %s: %m", filename);
569 ppp_option_error("Can't open options file %s: %m", filename);
573 oldpriv = privileged_option;
574 privileged_option = priv;
575 oldsource = option_source;
576 option_source = strdup(filename);
577 if (option_source == NULL)
578 option_source = "file";
580 while (getword(f, cmd, &newline, filename)) {
581 opt = find_option(cmd);
583 ppp_option_error("In file %s: unrecognized option '%s'",
587 n = n_arguments(opt);
588 for (i = 0; i < n; ++i) {
589 if (!getword(f, args[i], &newline, filename)) {
591 "In file %s: too few parameters for option '%s'",
597 if (!process_option(opt, cmd, argv))
604 privileged_option = oldpriv;
605 option_source = oldsource;
610 * options_from_user - See if the use has a ~/.ppprc file,
611 * and if so, interpret options from it.
614 options_from_user(void)
616 char *user, *path, *file;
621 pw = getpwuid(getuid());
622 if (pw == NULL || (user = pw->pw_dir) == NULL || user[0] == 0)
624 file = PPP_PATH_USEROPT;
625 pl = strlen(user) + strlen(file) + 2;
628 novm("init file name");
629 slprintf(path, pl, "%s/%s", user, file);
630 option_priority = OPRIO_CFGFILE;
631 ret = ppp_options_from_file(path, 0, 1, privileged);
637 * options_for_tty - See if an options file exists for the serial
638 * device, and if so, interpret options from it.
639 * We only allow the per-tty options file to override anything from
640 * the command line if it is something that the user can't override
641 * once it has been set by root; this is done by giving configuration
642 * files a lower priority than the command line.
645 options_for_tty(void)
647 char *dev, *path, *p;
652 if ((p = strstr(dev, "/dev/")) != NULL)
654 if (dev[0] == 0 || strcmp(dev, "tty") == 0)
655 return 1; /* don't look for /etc/ppp/options.tty */
656 pl = strlen(PPP_PATH_TTYOPT) + strlen(dev) + 1;
659 novm("tty init file name");
660 slprintf(path, pl, "%s%s", PPP_PATH_TTYOPT, dev);
661 /* Turn slashes into dots, for Solaris case (e.g. /dev/term/a) */
662 for (p = path + strlen(PPP_PATH_TTYOPT); *p != 0; ++p)
665 option_priority = OPRIO_CFGFILE;
666 ret = ppp_options_from_file(path, 0, 0, 1);
672 * options_from_list - process a string of options in a wordlist.
675 options_from_list(struct wordlist *w, int priv)
682 privileged_option = priv;
683 option_source = "secrets file";
684 option_priority = OPRIO_SECFILE;
687 opt = find_option(w->word);
689 ppp_option_error("In secrets file: unrecognized option '%s'",
693 n = n_arguments(opt);
695 for (i = 0; i < n; ++i) {
699 "In secrets file: too few parameters for option '%s'",
705 if (!process_option(opt, w0->word, argv))
716 * match_option - see if this option matches an option structure.
719 match_option(char *name, struct option *opt, int dowild)
721 int (*match)(char *, char **, int);
723 if (dowild != (opt->type == o_wild))
726 return strcmp(name, opt->name) == 0;
727 match = (int (*)(char *, char **, int)) opt->addr;
728 return (*match)(name, NULL, 0);
732 * find_option - scan the option lists for the various protocols
733 * looking for an entry with the given name.
734 * This could be optimized by using a hash table.
736 static struct option *
737 find_option(char *name)
740 struct option_list *list;
743 for (dowild = 0; dowild <= 1; ++dowild) {
744 for (opt = general_options; opt->name != NULL; ++opt)
745 if (match_option(name, opt, dowild))
747 for (opt = auth_options; opt->name != NULL; ++opt)
748 if (match_option(name, opt, dowild))
750 for (list = extra_options; list != NULL; list = list->next)
751 for (opt = list->options; opt->name != NULL; ++opt)
752 if (match_option(name, opt, dowild))
754 for (opt = the_channel->options; opt->name != NULL; ++opt)
755 if (match_option(name, opt, dowild))
757 for (i = 0; protocols[i] != NULL; ++i)
758 if ((opt = protocols[i]->options) != NULL)
759 for (; opt->name != NULL; ++opt)
760 if (match_option(name, opt, dowild))
767 * process_option - process one new-style option.
770 process_option(struct option *opt, char *cmd, char **argv)
775 int (*parser)(char **);
776 int (*wildp)(char *, char **, int);
777 char *optopt = (opt->type == o_wild)? "": " option";
778 int prio = option_priority;
779 struct option *mainopt = opt;
781 current_option = opt->name;
782 if ((opt->flags & OPT_PRIVFIX) && privileged_option)
784 while (mainopt->flags & OPT_PRIOSUB)
786 if (mainopt->flags & OPT_PRIO) {
787 if (prio < mainopt->priority) {
788 /* new value doesn't override old */
789 if (prio == OPRIO_CMDLINE && mainopt->priority > OPRIO_ROOT) {
790 ppp_option_error("%s%s set in %s cannot be overridden\n",
791 opt->name, optopt, mainopt->source);
796 if (prio > OPRIO_ROOT && mainopt->priority == OPRIO_CMDLINE)
797 warn("%s%s from %s overrides command line",
798 opt->name, optopt, option_source);
801 if ((opt->flags & OPT_INITONLY) && !in_phase(PHASE_INITIALIZE)) {
802 ppp_option_error("%s%s cannot be changed after initialization",
806 if ((opt->flags & OPT_PRIV) && !privileged_option) {
807 ppp_option_error("using the %s%s requires root privilege",
811 if ((opt->flags & OPT_ENABLE) && *(bool *)(opt->addr2) == 0) {
812 ppp_option_error("%s%s is disabled", opt->name, optopt);
815 if ((opt->flags & OPT_DEVEQUIV) && devnam_fixed) {
816 ppp_option_error("the %s%s may not be changed in %s",
817 opt->name, optopt, option_source);
823 v = opt->flags & OPT_VALUE;
824 *(bool *)(opt->addr) = v;
825 if (opt->addr2 && (opt->flags & OPT_A2COPY))
826 *(bool *)(opt->addr2) = v;
827 else if (opt->addr2 && (opt->flags & OPT_A2CLR))
828 *(bool *)(opt->addr2) = 0;
829 else if (opt->addr2 && (opt->flags & OPT_A2CLRB))
830 *(u_char *)(opt->addr2) &= ~v;
831 else if (opt->addr2 && (opt->flags & OPT_A2OR))
832 *(u_char *)(opt->addr2) |= v;
837 if ((opt->flags & OPT_NOARG) == 0) {
838 if (!ppp_int_option(*argv, &iv))
840 if ((((opt->flags & OPT_LLIMIT) && iv < opt->lower_limit)
841 || ((opt->flags & OPT_ULIMIT) && iv > opt->upper_limit))
842 && !((opt->flags & OPT_ZEROOK && iv == 0))) {
843 char *zok = (opt->flags & OPT_ZEROOK)? " zero or": "";
844 switch (opt->flags & OPT_LIMITS) {
846 ppp_option_error("%s value must be%s >= %d",
847 opt->name, zok, opt->lower_limit);
850 ppp_option_error("%s value must be%s <= %d",
851 opt->name, zok, opt->upper_limit);
854 ppp_option_error("%s value must be%s between %d and %d",
855 opt->name, zok, opt->lower_limit, opt->upper_limit);
861 a = opt->flags & OPT_VALUE;
863 a -= 256; /* sign extend */
865 if (opt->flags & OPT_INC)
866 iv += *(int *)(opt->addr);
867 if ((opt->flags & OPT_NOINCR) && !privileged_option) {
868 int oldv = *(int *)(opt->addr);
869 if ((opt->flags & OPT_ZEROINF) ?
870 (oldv != 0 && (iv == 0 || iv > oldv)) : (iv > oldv)) {
871 ppp_option_error("%s value cannot be increased", opt->name);
875 *(int *)(opt->addr) = iv;
876 if (opt->addr2 && (opt->flags & OPT_A2COPY))
877 *(int *)(opt->addr2) = iv;
881 if (opt->flags & OPT_NOARG) {
882 v = opt->flags & OPT_VALUE;
885 } else if (!number_option(*argv, &v, 16))
887 if (opt->flags & OPT_OR)
888 v |= *(u_int32_t *)(opt->addr);
889 *(u_int32_t *)(opt->addr) = v;
890 if (opt->addr2 && (opt->flags & OPT_A2COPY))
891 *(u_int32_t *)(opt->addr2) = v;
895 if (opt->flags & OPT_STATIC) {
896 strlcpy((char *)(opt->addr), *argv, opt->upper_limit);
898 char **optptr = (char **)(opt->addr);
901 novm("option argument");
906 /* obfuscate original argument for things like password */
907 if (opt->flags & OPT_HIDE) {
908 memset(*argv, '?', strlen(*argv));
913 case o_special_noarg:
915 parser = (int (*)(char **)) opt->addr;
917 if (!(*parser)(argv))
919 if (opt->flags & OPT_A2LIST) {
920 struct option_value *ovp, *pp;
922 ovp = malloc(sizeof(*ovp) + strlen(*argv));
924 strcpy(ovp->value, *argv);
925 ovp->source = option_source;
927 if (opt->addr2 == NULL) {
930 for (pp = opt->addr2; pp->next != NULL; pp = pp->next)
939 wildp = (int (*)(char *, char **, int)) opt->addr;
940 if (!(*wildp)(cmd, argv, 1))
946 * If addr2 wasn't used by any flag (OPT_A2COPY, etc.) but is set,
947 * treat it as a bool and set/clear it based on the OPT_A2CLR bit.
949 if (opt->addr2 && (opt->flags & (OPT_A2COPY|OPT_ENABLE
950 |OPT_A2PRINTER|OPT_A2STRVAL|OPT_A2LIST|OPT_A2OR)) == 0)
951 *(bool *)(opt->addr2) = !(opt->flags & OPT_A2CLR);
953 mainopt->source = option_source;
954 mainopt->priority = prio;
955 mainopt->winner = opt - mainopt;
961 * override_value - if the option priorities would permit us to
962 * override the value of option, return 1 and update the priority
963 * and source of the option value. Otherwise returns 0.
966 override_value(char *option, int priority, const char *source)
970 opt = find_option(option);
973 while (opt->flags & OPT_PRIOSUB)
975 if ((opt->flags & OPT_PRIO) && priority < opt->priority)
977 opt->priority = priority;
978 opt->source = source;
984 * n_arguments - tell how many arguments an option takes
987 n_arguments(struct option *opt)
989 return (opt->type == o_bool || opt->type == o_special_noarg
990 || (opt->flags & OPT_NOARG))? 0: 1;
994 * add_options - add a list of options to the set we grok.
997 ppp_add_options(struct option *opt)
999 struct option_list *list;
1001 list = malloc(sizeof(*list));
1003 novm("option list entry");
1004 list->options = opt;
1005 list->next = extra_options;
1006 extra_options = list;
1010 * check_options - check that options are valid and consistent.
1015 if (logfile_fd >= 0 && logfile_fd != log_to_fd)
1020 * print_option - print out an option and its value
1023 print_option(struct option *opt, struct option *mainopt, printer_func printer, void *arg)
1028 if (opt->flags & OPT_NOPRINT)
1030 switch (opt->type) {
1032 v = opt->flags & OPT_VALUE;
1033 if (*(bool *)opt->addr != v)
1034 /* this can happen legitimately, e.g. lock
1035 option turned off for default device */
1037 printer(arg, "%s", opt->name);
1040 v = opt->flags & OPT_VALUE;
1043 i = *(int *)opt->addr;
1044 if (opt->flags & OPT_NOARG) {
1045 printer(arg, "%s", opt->name);
1047 if (opt->flags & OPT_INC) {
1048 for (; i > v; i -= v)
1049 printer(arg, " %s", opt->name);
1051 printer(arg, " # oops: %d not %d\n",
1055 printer(arg, "%s %d", opt->name, i);
1059 printer(arg, "%s", opt->name);
1060 if ((opt->flags & OPT_NOARG) == 0)
1061 printer(arg, " %x", *(u_int32_t *)opt->addr);
1065 if (opt->flags & OPT_HIDE) {
1068 p = (char *) opt->addr;
1069 if ((opt->flags & OPT_STATIC) == 0)
1072 printer(arg, "%s %q", opt->name, p);
1076 case o_special_noarg:
1078 if (opt->type != o_wild) {
1079 printer(arg, "%s", opt->name);
1080 if (n_arguments(opt) == 0)
1084 if (opt->flags & OPT_A2PRINTER) {
1085 void (*oprt)(struct option *, printer_func, void *);
1086 oprt = (void (*)(struct option *, printer_func, void *))
1088 (*oprt)(opt, printer, arg);
1089 } else if (opt->flags & OPT_A2STRVAL) {
1090 p = (char *) opt->addr2;
1091 if ((opt->flags & OPT_STATIC) == 0)
1093 printer(arg, "%q", p);
1094 } else if (opt->flags & OPT_A2LIST) {
1095 struct option_value *ovp;
1097 ovp = (struct option_value *) opt->addr2;
1099 printer(arg, "%q", ovp->value);
1100 if ((ovp = ovp->next) == NULL)
1102 printer(arg, "\t\t# (from %s)\n%s ",
1103 ovp->source, opt->name);
1106 printer(arg, "xxx # [don't know how to print value]");
1111 printer(arg, "# %s value (type %d\?\?)", opt->name, opt->type);
1114 printer(arg, "\t\t# (from %s)\n", mainopt->source);
1118 * print_option_list - print out options in effect from an
1122 print_option_list(struct option *opt, printer_func printer, void *arg)
1124 while (opt->name != NULL) {
1125 if (opt->priority != OPRIO_DEFAULT
1126 && opt->winner != (short int) -1)
1127 print_option(opt + opt->winner, opt, printer, arg);
1130 } while (opt->flags & OPT_PRIOSUB);
1135 * print_options - print out what options are in effect.
1138 print_options(printer_func printer, void *arg)
1140 struct option_list *list;
1143 printer(arg, "pppd options in effect:\n");
1144 print_option_list(general_options, printer, arg);
1145 print_option_list(auth_options, printer, arg);
1146 for (list = extra_options; list != NULL; list = list->next)
1147 print_option_list(list->options, printer, arg);
1148 print_option_list(the_channel->options, printer, arg);
1149 for (i = 0; protocols[i] != NULL; ++i)
1150 print_option_list(protocols[i]->options, printer, arg);
1154 * usage - print out a message telling how to use the program.
1160 if (in_phase(PHASE_INITIALIZE)) {
1161 fprintf(fp, "%s v%s\n", PACKAGE_NAME, PACKAGE_VERSION);
1162 fprintf(fp, "Copyright (C) 1999-2022 Paul Mackerras, and others. All rights reserved.\n\n");
1165 fprintf(fp, "License BSD: The 3 clause BSD license <https://opensource.org/licenses/BSD-3-Clause>\n");
1166 fprintf(fp, "This is free software: you are free to change and redistribute it.\n");
1167 fprintf(fp, "There is NO WARRANTY, to the extent permitted by law.\n\n");
1169 fprintf(fp, "Report Bugs:\n %s\n\n", PACKAGE_BUGREPORT);
1170 fprintf(fp, "Usage: %s [ options ], where options are:\n", progname);
1171 fprintf(fp, " <device> Communicate over the named device\n");
1172 fprintf(fp, " <speed> Set the baud rate to <speed>\n");
1173 fprintf(fp, " <loc>:<rem> Set the local and/or remote interface IP\n");
1174 fprintf(fp, " addresses. Either one may be omitted.\n");
1175 fprintf(fp, " asyncmap <n> Set the desired async map to hex <n>\n");
1176 fprintf(fp, " auth Require authentication from peer\n");
1177 fprintf(fp, " connect <p> Invoke shell command <p> to set up the serial line\n");
1178 fprintf(fp, " crtscts Use hardware RTS/CTS flow control\n");
1179 fprintf(fp, " defaultroute Add default route through interface\n");
1180 fprintf(fp, " file <f> Take options from file <f>\n");
1181 fprintf(fp, " modem Use modem control lines\n");
1182 fprintf(fp, " mru <n> Set MRU value to <n> for negotiation\n");
1183 fprintf(fp, " show-options Display an extended list of options\n");
1184 fprintf(fp, "See pppd(8) for more options.\n");
1189 * showhelp - print out usage message and exit.
1192 showhelp(char **argv)
1194 if (in_phase(PHASE_INITIALIZE)) {
1202 * showversion - print out the version number and exit.
1205 showversion(char **argv)
1207 if (in_phase(PHASE_INITIALIZE)) {
1208 fprintf(stdout, "pppd version %s\n", VERSION);
1215 * Print a set of options including the name of the group of options
1218 showopts_list(FILE *fp, const char *title, struct option *list, ...)
1220 struct option *opt = list;
1223 if (opt && opt->name) {
1224 va_start(varg, list);
1225 vfprintf(fp, title, varg);
1230 fprintf(fp, " %-22s %s\n", opt->name, opt->description?:"");
1232 } while (opt && opt->name);
1239 * Dumps the list of available options
1244 struct option_list *list;
1248 showopts_list(fp, "General Options",
1251 showopts_list(fp, "Authentication Options",
1254 for (list = extra_options; list != NULL; list = list->next)
1255 showopts_list(fp, "Extra Options", list->options);
1257 showopts_list(fp, "Channel Options",
1258 the_channel->options);
1260 for (i = 0; protocols[i] != NULL; ++i) {
1261 if (protocols[i]->options != NULL) {
1262 showopts_list(fp, "%s Options",
1263 protocols[i]->options,
1264 protocols[i]->name);
1270 * ppp_option_error - print a message about an error in an option.
1271 * The message is logged, and also sent to
1272 * stderr if in_phase(PHASE_INITIALIZE).
1275 ppp_option_error(char *fmt, ...)
1280 va_start(args, fmt);
1281 vslprintf(buf, sizeof(buf), fmt, args);
1283 if (in_phase(PHASE_INITIALIZE))
1284 fprintf(stderr, "%s: %s\n", progname, buf);
1285 syslog(LOG_ERR, "%s", buf);
1290 * readable - check if a file is readable by the real user.
1302 if (fstat(fd, &sbuf) != 0)
1304 if (sbuf.st_uid == uid)
1305 return sbuf.st_mode & S_IRUSR;
1306 if (sbuf.st_gid == getgid())
1307 return sbuf.st_mode & S_IRGRP;
1308 for (i = 0; i < ngroups; ++i)
1309 if (sbuf.st_gid == groups[i])
1310 return sbuf.st_mode & S_IRGRP;
1311 return sbuf.st_mode & S_IROTH;
1316 * Read a word from a file.
1317 * Words are delimited by white-space or by quotes (" or ').
1318 * Quotes, white-space and \ may be escaped with \.
1319 * \<newline> is ignored.
1322 getword(FILE *f, char *word, int *newlinep, char *filename)
1325 int quoted, comment;
1326 int value, digit, got, n;
1328 #define isoctal(c) ((c) >= '0' && (c) < '8')
1337 * First skip white-space and comments.
1345 * A newline means the end of a comment; backslash-newline
1346 * is ignored. Note that we cannot have escape && comment.
1358 * Ignore characters other than newline in a comment.
1364 * If this character is escaped, we have a word start.
1370 * If this is the escape character, look at the next character.
1378 * If this is the start of a comment, ignore the rest of the line.
1386 * A non-whitespace character is the start of a word.
1393 * Process characters until the end of the word.
1398 * This character is escaped: backslash-newline is ignored,
1399 * various other characters indicate particular values
1400 * as for C backslash-escapes.
1435 * \ddd octal sequence
1438 for (n = 0; n < 3 && isoctal(c); ++n) {
1439 value = (value << 3) + (c & 07);
1448 * \x<hex_string> sequence
1452 for (n = 0; n < 2 && isxdigit(c); ++n) {
1453 digit = toupper(c) - '0';
1455 digit += '0' + 10 - 'A';
1456 value = (value << 4) + digit;
1464 * Otherwise the character stands for itself.
1471 * Store the resulting character for the escape sequence.
1473 if (len < MAXWORDLEN) {
1484 * Backslash starts a new escape sequence.
1493 * Not escaped: check for the start or end of a quoted
1494 * section and see if we've reached the end of the word.
1502 } else if (c == '"' || c == '\'') {
1506 } else if (isspace(c) || c == '#') {
1512 * An ordinary character: store it in the word and get another.
1514 if (len < MAXWORDLEN) {
1521 word[MAXWORDLEN-1] = 0; /* make sure word is null-terminated */
1524 * End of the word: check for errors.
1530 ppp_option_error("Error reading %s: %m", filename);
1534 * If len is zero, then we didn't find a word before the
1540 ppp_option_error("warning: quoted word runs to end of file (%.20s...)",
1545 * Warn if the word was too long, and append a terminating null.
1547 if (len >= MAXWORDLEN) {
1548 ppp_option_error("warning: word in file %s too long (%.20s...)",
1550 len = MAXWORDLEN - 1;
1561 * number_option - parse an unsigned numeric parameter for an option.
1564 number_option(char *str, u_int32_t *valp, int base)
1568 *valp = strtoul(str, &ptr, base);
1570 ppp_option_error("invalid numeric parameter '%s' for %s option",
1571 str, current_option);
1579 * int_option - like number_option, but valp is int *,
1580 * the base is assumed to be 0, and *valp is not changed
1581 * if there is an error.
1584 ppp_int_option(char *str, int *valp)
1588 if (!number_option(str, &v, 0))
1596 * The following procedures parse options.
1600 * readfile - take commands from a file.
1603 readfile(char **argv)
1605 return ppp_options_from_file(*argv, 1, 1, privileged_option);
1609 * callfile - take commands from /etc/ppp/peers/<name>.
1610 * Name may not contain /../, start with / or ../, or end in /..
1613 callfile(char **argv)
1615 char *fname, *arg, *p;
1620 if (arg[0] == '/' || arg[0] == 0)
1623 for (p = arg; *p != 0; ) {
1624 if (p[0] == '.' && p[1] == '.' && (p[2] == '/' || p[2] == 0)) {
1628 while (*p != '/' && *p != 0)
1635 ppp_option_error("call option value may not contain .. or start with /");
1639 l = strlen(arg) + strlen(PPP_PATH_PEERFILES) + 1;
1640 if ((fname = (char *) malloc(l)) == NULL)
1641 novm("call file name");
1642 slprintf(fname, l, "%s%s", PPP_PATH_PEERFILES, arg);
1643 ppp_script_setenv("CALL_FILE", arg, 0);
1645 ok = ppp_options_from_file(fname, 1, 1, 1);
1651 #ifdef PPP_WITH_FILTER
1653 * setpassfilter - Set the pass filter for packets
1656 setpassfilter(char **argv)
1661 pc = pcap_open_dead(DLT_PPP_PPPD, 65535);
1662 if (pcap_compile(pc, &pass_filter, *argv, 1, netmask) == -1) {
1663 ppp_option_error("error in pass-filter expression: %s\n",
1673 * setactivefilter - Set the active filter for packets
1676 setactivefilter(char **argv)
1681 pc = pcap_open_dead(DLT_PPP_PPPD, 65535);
1682 if (pcap_compile(pc, &active_filter, *argv, 1, netmask) == -1) {
1683 ppp_option_error("error in active-filter expression: %s\n",
1694 * setdomain - Set domain name to append to hostname
1697 setdomain(char **argv)
1699 gethostname(hostname, MAXNAMELEN);
1702 strncat(hostname, ".", MAXNAMELEN - strlen(hostname));
1703 domain = hostname + strlen(hostname);
1704 strncat(hostname, *argv, MAXNAMELEN - strlen(hostname));
1706 hostname[MAXNAMELEN-1] = 0;
1711 setlogfile(char **argv)
1717 if (!privileged_option && seteuid(getuid()) == -1) {
1718 ppp_option_error("unable to drop permissions to open %s: %m", *argv);
1721 fd = open(*argv, O_WRONLY | O_APPEND | O_CREAT | O_EXCL, 0644);
1722 if (fd < 0 && errno == EEXIST)
1723 fd = open(*argv, O_WRONLY | O_APPEND);
1725 if (!privileged_option && seteuid(euid) == -1)
1726 fatal("unable to regain privileges: %m");
1729 ppp_option_error("Can't open log file %s: %m", *argv);
1732 strlcpy(logfile_name, *argv, sizeof(logfile_name));
1733 if (logfile_fd >= 0)
1742 setmodir(char **argv)
1746 if(!strcmp(*argv,"in")) {
1747 maxoctets_dir = PPP_OCTETS_DIRECTION_IN;
1748 } else if (!strcmp(*argv,"out")) {
1749 maxoctets_dir = PPP_OCTETS_DIRECTION_OUT;
1750 } else if (!strcmp(*argv,"max")) {
1751 maxoctets_dir = PPP_OCTETS_DIRECTION_MAXOVERAL;
1753 maxoctets_dir = PPP_OCTETS_DIRECTION_SUM;
1758 #ifdef PPP_WITH_PLUGINS
1760 loadplugin(char **argv)
1769 if (strchr(arg, '/') == 0) {
1770 const char *base = PPP_PATH_PLUGIN;
1771 int l = strlen(base) + strlen(arg) + 2;
1774 novm("plugin file path");
1775 strlcpy(path, base, l);
1776 strlcat(path, "/", l);
1777 strlcat(path, arg, l);
1779 handle = dlopen(path, RTLD_GLOBAL | RTLD_NOW);
1783 ppp_option_error("%s", err);
1784 ppp_option_error("Couldn't load plugin %s", arg);
1787 init = (void (*)(void))dlsym(handle, "plugin_init");
1789 ppp_option_error("%s has no initialization entry point", arg);
1792 vers = (const char *) dlsym(handle, "pppd_version");
1794 warn("Warning: plugin %s has no version information", arg);
1795 } else if (strcmp(vers, VERSION) != 0) {
1796 ppp_option_error("Plugin %s is for pppd version %s, this is %s",
1797 arg, vers, VERSION);
1800 info("Plugin %s loaded.", arg);
1813 #endif /* PPP_WITH_PLUGINS */
1816 * Set an environment variable specified by the user.
1819 user_setenv(char **argv)
1821 char *arg = argv[0];
1823 struct userenv *uep, **insp;
1825 if ((eqp = strchr(arg, '=')) == NULL) {
1826 ppp_option_error("missing = in name=value: %s", arg);
1830 ppp_option_error("missing variable name: %s", arg);
1833 for (uep = userenv_list; uep != NULL; uep = uep->ue_next) {
1834 int nlen = strlen(uep->ue_name);
1835 if (nlen == (eqp - arg) &&
1836 strncmp(arg, uep->ue_name, nlen) == 0)
1839 /* Ignore attempts by unprivileged users to override privileged sources */
1840 if (uep != NULL && !privileged_option && uep->ue_priv)
1842 /* The name never changes, so allocate it with the structure */
1844 uep = malloc(sizeof (*uep) + (eqp-arg));
1846 novm("environment variable");
1849 strncpy(uep->ue_name, arg, eqp-arg);
1850 uep->ue_name[eqp-arg] = '\0';
1851 uep->ue_next = NULL;
1852 insp = &userenv_list;
1853 while (*insp != NULL)
1854 insp = &(*insp)->ue_next;
1857 struct userenv *uep2;
1858 for (uep2 = userenv_list; uep2 != NULL; uep2 = uep2->ue_next) {
1859 if (uep2 != uep && !uep2->ue_isset)
1862 if (uep2 == NULL && !uep->ue_isset)
1863 find_option("unset")->flags |= OPT_NOPRINT;
1864 free(uep->ue_value);
1867 uep->ue_priv = privileged_option;
1868 uep->ue_source = option_source;
1869 uep->ue_value = strdup(eqp + 1);
1870 curopt->flags &= ~OPT_NOPRINT;
1875 user_setprint(struct option *opt, printer_func printer, void *arg)
1877 struct userenv *uep, *uepnext;
1879 uepnext = userenv_list;
1880 while (uepnext != NULL && !uepnext->ue_isset)
1881 uepnext = uepnext->ue_next;
1882 while ((uep = uepnext) != NULL) {
1883 uepnext = uep->ue_next;
1884 while (uepnext != NULL && !uepnext->ue_isset)
1885 uepnext = uepnext->ue_next;
1886 (*printer)(arg, "%s=%s", uep->ue_name, uep->ue_value);
1887 if (uepnext != NULL)
1888 (*printer)(arg, "\t\t# (from %s)\n%s ", uep->ue_source, opt->name);
1890 opt->source = uep->ue_source;
1895 user_unsetenv(char **argv)
1897 struct userenv *uep, **insp;
1898 char *arg = argv[0];
1900 if (strchr(arg, '=') != NULL) {
1901 ppp_option_error("unexpected = in name: %s", arg);
1905 ppp_option_error("missing variable name for unset");
1908 for (uep = userenv_list; uep != NULL; uep = uep->ue_next) {
1909 if (strcmp(arg, uep->ue_name) == 0)
1912 /* Ignore attempts by unprivileged users to override privileged sources */
1913 if (uep != NULL && !privileged_option && uep->ue_priv)
1915 /* The name never changes, so allocate it with the structure */
1917 uep = malloc(sizeof (*uep) + strlen(arg));
1919 novm("environment variable");
1922 strcpy(uep->ue_name, arg);
1923 uep->ue_next = NULL;
1924 insp = &userenv_list;
1925 while (*insp != NULL)
1926 insp = &(*insp)->ue_next;
1929 struct userenv *uep2;
1930 for (uep2 = userenv_list; uep2 != NULL; uep2 = uep2->ue_next) {
1931 if (uep2 != uep && uep2->ue_isset)
1934 if (uep2 == NULL && uep->ue_isset)
1935 find_option("set")->flags |= OPT_NOPRINT;
1936 free(uep->ue_value);
1939 uep->ue_priv = privileged_option;
1940 uep->ue_source = option_source;
1941 uep->ue_value = NULL;
1942 curopt->flags &= ~OPT_NOPRINT;
1947 user_unsetprint(struct option *opt, printer_func printer, void *arg)
1949 struct userenv *uep, *uepnext;
1951 uepnext = userenv_list;
1952 while (uepnext != NULL && uepnext->ue_isset)
1953 uepnext = uepnext->ue_next;
1954 while ((uep = uepnext) != NULL) {
1955 uepnext = uep->ue_next;
1956 while (uepnext != NULL && uepnext->ue_isset)
1957 uepnext = uepnext->ue_next;
1958 (*printer)(arg, "%s", uep->ue_name);
1959 if (uepnext != NULL)
1960 (*printer)(arg, "\t\t# (from %s)\n%s ", uep->ue_source, opt->name);
1962 opt->source = uep->ue_source;