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      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 (at) 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
    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
    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
    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
    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
    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
    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 *
    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
    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
    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
    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
    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
    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
    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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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
   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