xref: /trueos/contrib/amd/amd/opts.c (revision 2e06911c043c995eb8eb5f67a778b74564d0c018)
1 /*
2  * Copyright (c) 1997-2006 Erez Zadok
3  * Copyright (c) 1989 Jan-Simon Pendry
4  * Copyright (c) 1989 Imperial College of Science, Technology & Medicine
5  * Copyright (c) 1989 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Jan-Simon Pendry at Imperial College, London.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgment:
21  *      This product includes software developed by the University of
22  *      California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  *
40  * File: am-utils/amd/opts.c
41  *
42  */
43 
44 #ifdef HAVE_CONFIG_H
45 # include <config.h>
46 #endif /* HAVE_CONFIG_H */
47 #include <am_defs.h>
48 #include <amd.h>
49 
50 /*
51  * MACROS:
52  */
53 #define	NLEN	16	/* Length of longest option name (conservative) */
54 #define S(x) (x) , (sizeof(x)-1)
55 /*
56  * The BUFSPACE macros checks that there is enough space
57  * left in the expansion buffer.  If there isn't then we
58  * give up completely.  This is done to avoid crashing the
59  * automounter itself (which would be a bad thing to do).
60  */
61 #define BUFSPACE(ep, len) (((ep) + (len)) < expbuf+MAXPATHLEN)
62 
63 /*
64  * TYPEDEFS:
65  */
66 typedef int (*IntFuncPtr) (char *);
67 typedef struct opt_apply opt_apply;
68 enum vs_opt { SelEQ, SelNE, VarAss };
69 
70 /*
71  * STRUCTURES
72  */
73 struct opt {
74   char *name;			/* Name of the option */
75   int nlen;			/* Length of option name */
76   char **optp;			/* Pointer to option value string */
77   char **sel_p;			/* Pointer to selector value string */
78   int (*fxn_p)(char *);		/* Pointer to boolean function */
79   int case_insensitive;		/* How to do selector comparisons */
80 };
81 
82 struct opt_apply {
83   char **opt;
84   char *val;
85 };
86 
87 struct functable {
88   char *name;
89   IntFuncPtr func;
90 };
91 
92 /*
93  * FORWARD DEFINITION:
94  */
95 static int f_in_network(char *);
96 static int f_xhost(char *);
97 static int f_netgrp(char *);
98 static int f_netgrpd(char *);
99 static int f_exists(char *);
100 static int f_false(char *);
101 static int f_true(char *);
102 static inline char *expand_options(char *key);
103 
104 /*
105  * STATICS:
106  */
107 static char NullStr[] = "<NULL>";
108 static char nullstr[] = "";
109 static char *opt_dkey = NullStr;
110 static char *opt_host = nullstr; /* XXX: was the global hostname */
111 static char *opt_hostd = hostd;
112 static char *opt_key = nullstr;
113 static char *opt_keyd = nullstr;
114 static char *opt_map = nullstr;
115 static char *opt_path = nullstr;
116 char uid_str[SIZEOF_UID_STR], gid_str[SIZEOF_GID_STR];
117 char *opt_uid = uid_str;
118 char *opt_gid = gid_str;
119 static char *vars[8];
120 static char *literal_dollar = "$"; /* ${dollar}: a literal '$' in maps */
121 
122 /*
123  * GLOBALS
124  */
125 static struct am_opts fs_static;      /* copy of the options to play with */
126 
127 
128 /*
129  * Options in some order corresponding to frequency of use so that
130  * first-match algorithm is sped up.
131  */
132 static struct opt opt_fields[] = {
133   /* Name and length.
134 	Option str.		Selector str.	boolean fxn.	case sensitive */
135   { S("opts"),
136        &fs_static.opt_opts,	0,		0, 		FALSE	},
137   { S("host"),
138 	0,			&opt_host,	0,		TRUE	},
139   { S("hostd"),
140 	0,			&opt_hostd,	0,		TRUE	},
141   { S("type"),
142 	&fs_static.opt_type,	0,		0,		FALSE	},
143   { S("rhost"),
144 	&fs_static.opt_rhost,	0,		0,		TRUE	},
145   { S("rfs"),
146 	&fs_static.opt_rfs,	0,		0,		FALSE	},
147   { S("fs"),
148 	&fs_static.opt_fs,	0,		0,		FALSE	},
149   { S("key"),
150 	0,			&opt_key,	0,		FALSE	},
151   { S("map"),
152 	0,			&opt_map,	0,		FALSE	},
153   { S("sublink"),
154 	&fs_static.opt_sublink,	0,		0,		FALSE	},
155   { S("arch"),
156 	0,			&gopt.arch,	0,		TRUE	},
157   { S("dev"),
158 	&fs_static.opt_dev,	0,		0,		FALSE	},
159   { S("pref"),
160 	&fs_static.opt_pref,	0,		0,		FALSE	},
161   { S("path"),
162 	0,			&opt_path,	0,		FALSE	},
163   { S("autodir"),
164 	0,			&gopt.auto_dir,	0,		FALSE	},
165   { S("delay"),
166 	&fs_static.opt_delay,	0,		0,		FALSE	},
167   { S("domain"),
168 	0,			&hostdomain,	0,		TRUE	},
169   { S("karch"),
170 	0,			&gopt.karch,	0,		TRUE	},
171   { S("cluster"),
172 	0,			&gopt.cluster,	0,		TRUE	},
173   { S("wire"),
174 	0,			0,		f_in_network,	TRUE	},
175   { S("network"),
176 	0,			0,		f_in_network,	TRUE	},
177   { S("netnumber"),
178 	0,			0,		f_in_network,	TRUE	},
179   { S("byte"),
180 	0,			&endian,	0,		TRUE	},
181   { S("os"),
182 	0,			&gopt.op_sys,	0,		TRUE	},
183   { S("osver"),
184 	0,			&gopt.op_sys_ver,	0,	TRUE	},
185   { S("full_os"),
186 	0,			&gopt.op_sys_full,	0,	TRUE	},
187   { S("vendor"),
188 	0,			&gopt.op_sys_vendor,	0,	TRUE	},
189   { S("remopts"),
190 	&fs_static.opt_remopts,	0,		0,		FALSE	},
191   { S("mount"),
192 	&fs_static.opt_mount,	0,		0,		FALSE	},
193   { S("unmount"),
194 	&fs_static.opt_unmount,	0,		0,		FALSE	},
195   { S("umount"),
196 	&fs_static.opt_umount,	0,		0,		FALSE	},
197   { S("cache"),
198 	&fs_static.opt_cache,	0,		0,		FALSE	},
199   { S("user"),
200 	&fs_static.opt_user,	0,		0,		FALSE	},
201   { S("group"),
202 	&fs_static.opt_group,	0,		0,		FALSE	},
203   { S(".key"),
204 	0,			&opt_dkey,	0,		FALSE	},
205   { S("key."),
206 	0,			&opt_keyd,	0,		FALSE	},
207   { S("maptype"),
208 	&fs_static.opt_maptype,	0,		0,		FALSE	},
209   { S("cachedir"),
210 	&fs_static.opt_cachedir, 0,		0,		FALSE	},
211   { S("addopts"),
212 	&fs_static.opt_addopts,	0,		0, 		FALSE	},
213   { S("uid"),
214 	0,			&opt_uid,	0,		FALSE	},
215   { S("gid"),
216 	0,			&opt_gid,	0, 		FALSE	},
217   { S("mount_type"),
218 	&fs_static.opt_mount_type, 0,		0,		FALSE	},
219   { S("dollar"),
220 	&literal_dollar,	0,		0,		FALSE	},
221   { S("var0"),
222 	&vars[0],		0,		0,		FALSE	},
223   { S("var1"),
224 	&vars[1],		0,		0,		FALSE	},
225   { S("var2"),
226 	&vars[2],		0,		0,		FALSE	},
227   { S("var3"),
228 	&vars[3],		0,		0,		FALSE	},
229   { S("var4"),
230 	&vars[4],		0,		0,		FALSE	},
231   { S("var5"),
232 	&vars[5],		0,		0,		FALSE	},
233   { S("var6"),
234 	&vars[6],		0,		0,		FALSE	},
235   { S("var7"),
236 	&vars[7],		0,		0,		FALSE	},
237   { 0, 0, 0, 0, 0, FALSE },
238 };
239 
240 static struct functable functable[] = {
241   { "in_network",	f_in_network },
242   { "xhost",		f_xhost },
243   { "netgrp",		f_netgrp },
244   { "netgrpd",		f_netgrpd },
245   { "exists",		f_exists },
246   { "false",		f_false },
247   { "true",		f_true },
248   { 0, 0 },
249 };
250 
251 /*
252  * Specially expand the remote host name first
253  */
254 static opt_apply rhost_expansion[] =
255 {
256   {&fs_static.opt_rhost, "${host}"},
257   {0, 0},
258 };
259 
260 /*
261  * List of options which need to be expanded
262  * Note that the order here _may_ be important.
263  */
264 static opt_apply expansions[] =
265 {
266   {&fs_static.opt_sublink, 0},
267   {&fs_static.opt_rfs, "${path}"},
268   {&fs_static.opt_fs, "${autodir}/${rhost}${rfs}"},
269   {&fs_static.opt_opts, "rw"},
270   {&fs_static.opt_remopts, "${opts}"},
271   {&fs_static.opt_mount, 0},
272   {&fs_static.opt_unmount, 0},
273   {&fs_static.opt_umount, 0},
274   {&fs_static.opt_cachedir, 0},
275   {&fs_static.opt_addopts, 0},
276   {0, 0},
277 };
278 
279 /*
280  * List of options which need to be free'ed before re-use
281  */
282 static opt_apply to_free[] =
283 {
284   {&fs_static.fs_glob, 0},
285   {&fs_static.fs_local, 0},
286   {&fs_static.fs_mtab, 0},
287   {&fs_static.opt_sublink, 0},
288   {&fs_static.opt_rfs, 0},
289   {&fs_static.opt_fs, 0},
290   {&fs_static.opt_rhost, 0},
291   {&fs_static.opt_opts, 0},
292   {&fs_static.opt_remopts, 0},
293   {&fs_static.opt_mount, 0},
294   {&fs_static.opt_unmount, 0},
295   {&fs_static.opt_umount, 0},
296   {&fs_static.opt_cachedir, 0},
297   {&fs_static.opt_addopts, 0},
298   {&vars[0], 0},
299   {&vars[1], 0},
300   {&vars[2], 0},
301   {&vars[3], 0},
302   {&vars[4], 0},
303   {&vars[5], 0},
304   {&vars[6], 0},
305   {&vars[7], 0},
306   {0, 0},
307 };
308 
309 
310 /*
311  * expand backslash escape sequences
312  * (escaped slash is handled separately in normalize_slash)
313  */
314 static char
backslash(char ** p)315 backslash(char **p)
316 {
317   char c;
318 
319   if ((*p)[1] == '\0') {
320     plog(XLOG_USER, "Empty backslash escape");
321     return **p;
322   }
323 
324   if (**p == '\\') {
325     (*p)++;
326     switch (**p) {
327     case 'g':
328       c = '\007';		/* Bell */
329       break;
330     case 'b':
331       c = '\010';		/* Backspace */
332       break;
333     case 't':
334       c = '\011';		/* Horizontal Tab */
335       break;
336     case 'n':
337       c = '\012';		/* New Line */
338       break;
339     case 'v':
340       c = '\013';		/* Vertical Tab */
341       break;
342     case 'f':
343       c = '\014';		/* Form Feed */
344       break;
345     case 'r':
346       c = '\015';		/* Carriage Return */
347       break;
348     case 'e':
349       c = '\033';		/* Escape */
350       break;
351     case '0':
352     case '1':
353     case '2':
354     case '3':
355     case '4':
356     case '5':
357     case '6':
358     case '7':
359       {
360 	int cnt, val, ch;
361 
362 	for (cnt = 0, val = 0; cnt < 3; cnt++) {
363 	  ch = *(*p)++;
364 	  if (ch < '0' || ch > '7') {
365 	    (*p)--;
366 	    break;
367 	  }
368 	  val = (val << 3) | (ch - '0');
369 	}
370 
371 	if ((val & 0xffffff00) != 0)
372 	  plog(XLOG_USER,
373 	       "Too large character constant %u\n",
374 	       val);
375 	c = (char) val;
376 	--(*p);
377       }
378       break;
379 
380     default:
381       c = **p;
382       break;
383     }
384   } else
385     c = **p;
386 
387   return c;
388 }
389 
390 
391 /*
392  * Skip to next option in the string
393  */
394 static char *
opt(char ** p)395 opt(char **p)
396 {
397   char *cp = *p;
398   char *dp = cp;
399   char *s = cp;
400 
401 top:
402   while (*cp && *cp != ';') {
403     if (*cp == '"') {
404       /*
405        * Skip past string
406        */
407       for (cp++; *cp && *cp != '"'; cp++)
408 	if (*cp == '\\')
409 	  *dp++ = backslash(&cp);
410 	else
411 	  *dp++ = *cp;
412       if (*cp)
413 	cp++;
414     } else {
415       *dp++ = *cp++;
416     }
417   }
418 
419   /*
420    * Skip past any remaining ';'s
421    */
422   while (*cp == ';')
423     cp++;
424 
425   /*
426    * If we have a zero length string
427    * and there are more fields, then
428    * parse the next one.  This allows
429    * sequences of empty fields.
430    */
431   if (*cp && dp == s)
432     goto top;
433 
434   *dp = '\0';
435 
436   *p = cp;
437   return s;
438 }
439 
440 
441 /*
442  * These routines add a new style of selector; function-style boolean
443  * operators.  To add new ones, just define functions as in true, false,
444  * exists (below) and add them to the functable, above.
445  *
446  * Usage example: Some people have X11R5 local, some go to a server. I do
447  * this:
448  *
449  *    *       exists(/usr/pkg/${key});type:=link;fs:=/usr/pkg/${key} || \
450  *            -type:=nfs;rfs=/usr/pkg/${key} \
451  *            rhost:=server1 \
452  *            rhost:=server2
453  *
454  * -Rens Troost <rens@imsi.com>
455  */
456 static IntFuncPtr
functable_lookup(char * key)457 functable_lookup(char *key)
458 {
459   struct functable *fp;
460 
461   for (fp = functable; fp->name; fp++)
462     if (FSTREQ(fp->name, key))
463         return (fp->func);
464   return (IntFuncPtr) NULL;
465 }
466 
467 
468 /*
469  * Fill in the global structure fs_static by
470  * cracking the string opts.  opts may be
471  * scribbled on at will.  Does NOT evaluate options.
472  * Returns 0 on error, 1 if no syntax errors were discovered.
473  */
474 static int
split_opts(char * opts,char * mapkey)475 split_opts(char *opts, char *mapkey)
476 {
477   char *o = opts;
478   char *f;
479 
480   /*
481    * For each user-specified option
482    */
483   for (f = opt(&o); *f; f = opt(&o)) {
484     struct opt *op;
485     char *eq = strchr(f, '=');
486     char *opt = NULL;
487 
488     if (!eq)
489       continue;
490 
491     if (*(eq-1) == '!' ||
492 	eq[1] == '=' ||
493 	eq[1] == '!') {	/* != or == or =! */
494       continue;			/* we don't care about selectors */
495     }
496 
497     if (*(eq-1) == ':') {	/* := */
498       *(eq-1) = '\0';
499     } else {
500       /* old style assignment */
501       eq[0] = '\0';
502     }
503     opt = eq + 1;
504 
505     /*
506      * For each recognized option
507      */
508     for (op = opt_fields; op->name; op++) {
509       /*
510        * Check whether they match
511        */
512       if (FSTREQ(op->name, f)) {
513 	if (op->sel_p) {
514 	  plog(XLOG_USER, "key %s: Can't assign to a selector (%s)",
515 	       mapkey, op->name);
516 	  return 0;
517 	}
518 	*op->optp = opt;	/* actual assignment into fs_static */
519 	break;			/* break out of for loop */
520       }	/* end of "if (FSTREQ(op->name, f))" statement  */
521     } /* end of "for (op = opt_fields..." statement  */
522 
523     if (!op->name)
524       plog(XLOG_USER, "key %s: Unrecognized key/option \"%s\"", mapkey, f);
525   }
526 
527   return 1;
528 }
529 
530 
531 /*
532  * Just evaluate selectors, which were split by split_opts.
533  * Returns 0 on error or no match, 1 if matched.
534  */
535 static int
eval_selectors(char * opts,char * mapkey)536 eval_selectors(char *opts, char *mapkey)
537 {
538   char *o, *old_o;
539   char *f;
540   int ret = 0;
541 
542   o = old_o = strdup(opts);
543 
544   /*
545    * For each user-specified option
546    */
547   for (f = opt(&o); *f; f = opt(&o)) {
548     struct opt *op;
549     enum vs_opt vs_opt;
550     char *eq = strchr(f, '=');
551     char *fx;
552     IntFuncPtr func;
553     char *opt = NULL;
554     char *arg;
555 
556     if (!eq) {
557       /*
558        * No value, is it a function call?
559        */
560       arg = strchr(f, '(');
561 
562       if (!arg || arg[1] == '\0' || arg == f) {
563 	/*
564 	 * No, just continue
565 	 */
566 	plog(XLOG_USER, "key %s: No value component in \"%s\"", mapkey, f);
567 	continue;
568       }
569 
570       /* null-terminate the argument  */
571       *arg++ = '\0';
572       fx = strchr(arg, ')');
573       if (!arg || fx == arg) {
574 	plog(XLOG_USER, "key %s: Malformed function in \"%s\"", mapkey, f);
575 	continue;
576       }
577       *fx = '\0';
578 
579       if (f[0] == '!') {
580 	vs_opt = SelNE;
581 	f++;
582       } else {
583 	vs_opt = SelEQ;
584       }
585       /*
586        * look up f in functable and pass it arg.
587        * func must return 0 on failure, and 1 on success.
588        */
589       if ((func = functable_lookup(f))) {
590 	int funok;
591 
592 	/* this allocates memory, don't forget to free */
593 	arg = expand_options(arg);
594 	funok = func(arg);
595 	XFREE(arg);
596 
597 	if (vs_opt == SelNE)
598 	  funok = !funok;
599 	if (!funok)
600 	  goto out;
601 
602 	continue;
603       } else {
604 	plog(XLOG_USER, "key %s: unknown function \"%s\"", mapkey, f);
605 	goto out;
606       }
607     } else {
608       if (eq[1] == '\0' || eq == f) {
609 	/* misformed selector */
610 	plog(XLOG_USER, "key %s: Bad selector \"%s\"", mapkey, f);
611 	continue;
612       }
613     }
614 
615     /*
616      * Check what type of operation is happening
617      * !=, =!  is SelNE
618      * == is SelEQ
619      * =, := is VarAss
620      */
621     if (*(eq-1) == '!') {	/* != */
622       vs_opt = SelNE;
623       *(eq-1) = '\0';
624       opt = eq + 1;
625     } else if (*(eq-1) == ':') {	/* := */
626       continue;
627     } else if (eq[1] == '=') {	/* == */
628       vs_opt = SelEQ;
629       eq[0] = '\0';
630       opt = eq + 2;
631     } else if (eq[1] == '!') {	/* =! */
632       vs_opt = SelNE;
633       eq[0] = '\0';
634       opt = eq + 2;
635     } else {
636       /* old style assignment */
637       continue;
638     }
639 
640     /*
641      * For each recognized option
642      */
643     for (op = opt_fields; op->name; op++) {
644       /*
645        * Check whether they match
646        */
647       if (FSTREQ(op->name, f)) {
648 	opt = expand_options(opt);
649 
650 	if (op->sel_p != NULL) {
651 	  int selok;
652 	  if (op->case_insensitive) {
653 	    selok = STRCEQ(*op->sel_p, opt);
654 	  } else {
655 	    selok = STREQ(*op->sel_p, opt);
656 	  }
657 	  if (vs_opt == SelNE)
658 	    selok = !selok;
659 	  if (!selok) {
660 	    plog(XLOG_MAP, "key %s: map selector %s (=%s) did not %smatch %s",
661 		 mapkey,
662 		 op->name,
663 		 *op->sel_p,
664 		 vs_opt == SelNE ? "mis" : "",
665 		 opt);
666 	    XFREE(opt);
667 	    goto out;
668 	  }
669 	  XFREE(opt);
670 	}
671 	/* check if to apply a function */
672 	if (op->fxn_p) {
673 	  int funok;
674 
675 	  funok = op->fxn_p(opt);
676 	  if (vs_opt == SelNE)
677 	    funok = !funok;
678 	  if (!funok) {
679 	    plog(XLOG_MAP, "key %s: map function %s did not %smatch %s",
680 		 mapkey,
681 		 op->name,
682 		 vs_opt == SelNE ? "mis" : "",
683 		 opt);
684 	    XFREE(opt);
685 	    goto out;
686 	  }
687 	  XFREE(opt);
688 	}
689 	break;			/* break out of for loop */
690       }
691     }
692 
693     if (!op->name)
694       plog(XLOG_USER, "key %s: Unrecognized key/option \"%s\"", mapkey, f);
695   }
696 
697   /* all is ok */
698   ret = 1;
699 
700  out:
701   free(old_o);
702   return ret;
703 }
704 
705 
706 /*
707  * Skip to next option in the string, but don't scribble over the string.
708  * However, *p gets repointed to the start of the next string past ';'.
709  */
710 static char *
opt_no_scribble(char ** p)711 opt_no_scribble(char **p)
712 {
713   char *cp = *p;
714   char *dp = cp;
715   char *s = cp;
716 
717 top:
718   while (*cp && *cp != ';') {
719     if (*cp == '\"') {
720       /*
721        * Skip past string
722        */
723       cp++;
724       while (*cp && *cp != '\"')
725 	*dp++ = *cp++;
726       if (*cp)
727 	cp++;
728     } else {
729       *dp++ = *cp++;
730     }
731   }
732 
733   /*
734    * Skip past any remaining ';'s
735    */
736   while (*cp == ';')
737     cp++;
738 
739   /*
740    * If we have a zero length string
741    * and there are more fields, then
742    * parse the next one.  This allows
743    * sequences of empty fields.
744    */
745   if (*cp && dp == s)
746     goto top;
747 
748   *p = cp;
749   return s;
750 }
751 
752 
753 /*
754  * Strip any selectors from a string.  Selectors are all assumed to be
755  * first in the string.  This is used for the new /defaults method which will
756  * use selectors as well.
757  */
758 char *
strip_selectors(char * opts,char * mapkey)759 strip_selectors(char *opts, char *mapkey)
760 {
761   /*
762    * Fill in the global structure fs_static by
763    * cracking the string opts.  opts may be
764    * scribbled on at will.
765    */
766   char *o = opts;
767   char *oo = opts;
768   char *f;
769 
770   /*
771    * Scan options.  Note that the opt() function scribbles on the opt string.
772    */
773   while (*(f = opt_no_scribble(&o))) {
774     enum vs_opt vs_opt = VarAss;
775     char *eq = strchr(f, '=');
776 
777     if (!eq || eq[1] == '\0' || eq == f) {
778       /*
779        * No option or assignment?  Return as is.
780        */
781       plog(XLOG_USER, "key %s: No option or assignment in \"%s\"", mapkey, f);
782       return o;
783     }
784     /*
785      * Check what type of operation is happening
786      * !=, =!  is SelNE
787      * == is SelEQ
788      * := is VarAss
789      */
790     if (*(eq-1) == '!') {	/* != */
791       vs_opt = SelNE;
792     } else if (*(eq-1) == ':') {	/* := */
793       vs_opt = VarAss;
794     } else if (eq[1] == '=') {	/* == */
795       vs_opt = SelEQ;
796     } else if (eq[1] == '!') {	/* =! */
797       vs_opt = SelNE;
798     }
799     switch (vs_opt) {
800     case SelEQ:
801     case SelNE:
802       /* Skip this selector, maybe there's another one following it */
803       plog(XLOG_USER, "skipping selector to \"%s\"", o);
804       /* store previous match. it may have been the first assignment */
805       oo = o;
806       break;
807 
808     case VarAss:
809       /* found the first assignment, return the string starting with it */
810       dlog("found first assignment past selectors \"%s\"", o);
811       return oo;
812     }
813   }
814 
815   /* return the same string by default. should not happen. */
816   return oo;
817 }
818 
819 
820 /*****************************************************************************
821  *** BOOLEAN FUNCTIONS (return 0 if false, 1 if true):                     ***
822  *****************************************************************************/
823 
824 /* test if arg is any of this host's network names or numbers */
825 static int
f_in_network(char * arg)826 f_in_network(char *arg)
827 {
828   int status;
829 
830   if (!arg)
831     return 0;
832 
833   status = is_network_member(arg);
834   dlog("%s is %son a local network", arg, (status ? "" : "not "));
835   return status;
836 }
837 
838 
839 /*
840  * Test if arg is any of this host's names or aliases (CNAMES).
841  * Note: this function compares against the fully expanded host name (hostd).
842  * XXX: maybe we also need to compare against the stripped host name?
843  */
844 static int
f_xhost(char * arg)845 f_xhost(char *arg)
846 {
847   struct hostent *hp;
848   char **cp;
849 
850   if (!arg)
851     return 0;
852 
853   /* simple test: does it match main host name? */
854   if (STREQ(arg, opt_hostd))
855     return 1;
856 
857   /* now find all of the names of "arg" and compare against opt_hostd */
858   hp = gethostbyname(arg);
859   if (hp == NULL) {
860 #ifdef HAVE_HSTRERROR
861     plog(XLOG_ERROR, "gethostbyname xhost(%s): %s", arg, hstrerror(h_errno));
862 #else /* not HAVE_HSTRERROR */
863     plog(XLOG_ERROR, "gethostbyname xhost(%s): h_errno %d", arg, h_errno);
864 #endif /* not HAVE_HSTRERROR */
865     return 0;
866   }
867   /* check primary name */
868   if (hp->h_name) {
869     dlog("xhost: compare %s==%s", hp->h_name, opt_hostd);
870     if (STREQ(hp->h_name, opt_hostd)) {
871       plog(XLOG_INFO, "xhost(%s): matched h_name %s", arg, hp->h_name);
872       return 1;
873     }
874   }
875   /* check all aliases, if any */
876   if (hp->h_aliases == NULL) {
877     dlog("gethostbyname(%s) has no aliases", arg);
878     return 0;
879   }
880   cp = hp->h_aliases;
881   while (*cp) {
882     dlog("xhost: compare alias %s==%s", *cp, opt_hostd);
883     if (STREQ(*cp, opt_hostd)) {
884       plog(XLOG_INFO, "xhost(%s): matched alias %s", arg, *cp);
885       return 1;
886     }
887     cp++;
888   }
889   /* nothing matched */
890   return 0;
891 }
892 
893 
894 /* test if this host (short hostname form) is in netgroup (arg) */
895 static int
f_netgrp(char * arg)896 f_netgrp(char *arg)
897 {
898   int status;
899   char *ptr, *nhost;
900 
901   if ((ptr = strchr(arg, ',')) != NULL) {
902     *ptr = '\0';
903     nhost = ptr + 1;
904   } else {
905     nhost = opt_host;
906   }
907   status = innetgr(arg, nhost, NULL, NULL);
908   dlog("netgrp = %s status = %d host = %s", arg, status, nhost);
909   if (ptr)
910     *ptr = ',';
911   return status;
912 }
913 
914 
915 /* test if this host (fully-qualified name) is in netgroup (arg) */
916 static int
f_netgrpd(char * arg)917 f_netgrpd(char *arg)
918 {
919   int status;
920   char *ptr, *nhost;
921 
922   if ((ptr = strchr(arg, ',')) != NULL) {
923     *ptr = '\0';
924     nhost = ptr + 1;
925   } else {
926     nhost = opt_hostd;
927   }
928   status = innetgr(arg, nhost, NULL, NULL);
929   dlog("netgrp = %s status = %d hostd = %s", arg, status, nhost);
930   if (ptr)
931     *ptr = ',';
932   return status;
933 }
934 
935 
936 /* test if file (arg) exists via lstat */
937 static int
f_exists(char * arg)938 f_exists(char *arg)
939 {
940   struct stat buf;
941 
942   if (lstat(arg, &buf) < 0)
943     return (0);
944   else
945     return (1);
946 }
947 
948 
949 /* always false */
950 static int
f_false(char * arg)951 f_false(char *arg)
952 {
953   return (0);
954 }
955 
956 
957 /* always true */
958 static int
f_true(char * arg)959 f_true(char *arg)
960 {
961   return (1);
962 }
963 
964 
965 /*
966  * Free an option
967  */
968 static void
free_op(opt_apply * p,int b)969 free_op(opt_apply *p, int b)
970 {
971   if (*p->opt) {
972     XFREE(*p->opt);
973   }
974 }
975 
976 
977 /*
978  * Normalize slashes in the string.
979  */
980 void
normalize_slash(char * p)981 normalize_slash(char *p)
982 {
983   char *f, *f0;
984 
985   if (!(gopt.flags & CFM_NORMALIZE_SLASHES))
986     return;
987 
988   f0 = f = strchr(p, '/');
989   if (f) {
990     char *t = f;
991     do {
992       /* assert(*f == '/'); */
993       if (f == f0 && f[0] == '/' && f[1] == '/') {
994 	/* copy double slash iff first */
995 	*t++ = *f++;
996 	*t++ = *f++;
997       } else {
998 	/* copy a single / across */
999 	*t++ = *f++;
1000       }
1001 
1002       /* assert(f[-1] == '/'); */
1003       /* skip past more /'s */
1004       while (*f == '/')
1005 	f++;
1006 
1007       /* assert(*f != '/'); */
1008       /* keep copying up to next / */
1009       while (*f && *f != '/') {
1010 	/* support escaped slashes '\/' */
1011 	if (f[0] == '\\' && f[1] == '/')
1012 	  f++;			/* skip backslash */
1013 	*t++ = *f++;
1014       }
1015 
1016       /* assert(*f == 0 || *f == '/'); */
1017 
1018     } while (*f);
1019     *t = 0;			/* derived from fix by Steven Glassman */
1020   }
1021 }
1022 
1023 
1024 /*
1025  * Macro-expand an option.  Note that this does not
1026  * handle recursive expansions.  They will go badly wrong.
1027  * If sel_p is true then old expand selectors, otherwise
1028  * don't expand selectors.
1029  */
1030 static char *
expand_op(char * opt,int sel_p)1031 expand_op(char *opt, int sel_p)
1032 {
1033 #define EXPAND_ERROR "No space to expand \"%s\""
1034   char expbuf[MAXPATHLEN + 1];
1035   char nbuf[NLEN + 1];
1036   char *ep = expbuf;
1037   char *cp = opt;
1038   char *dp;
1039   struct opt *op;
1040   char *cp_orig = opt;
1041 
1042   while ((dp = strchr(cp, '$'))) {
1043     char ch;
1044     /*
1045      * First copy up to the $
1046      */
1047     {
1048       int len = dp - cp;
1049 
1050       if (len > 0) {
1051 	if (BUFSPACE(ep, len)) {
1052 	  /*
1053 	   * We use strncpy (not xstrlcpy) because 'ep' relies on its
1054 	   * semantics.  BUFSPACE guarantees that ep can hold len.
1055 	   */
1056 	  strncpy(ep, cp, len);
1057 	  ep += len;
1058 	} else {
1059 	  plog(XLOG_ERROR, EXPAND_ERROR, opt);
1060 	  goto out;
1061 	}
1062       }
1063     }
1064 
1065     cp = dp + 1;
1066     ch = *cp++;
1067     if (ch == '$') {
1068       if (BUFSPACE(ep, 1)) {
1069 	*ep++ = '$';
1070       } else {
1071 	plog(XLOG_ERROR, EXPAND_ERROR, opt);
1072 	goto out;
1073       }
1074     } else if (ch == '{') {
1075       /* Expansion... */
1076       enum {
1077 	E_All, E_Dir, E_File, E_Domain, E_Host
1078       } todo;
1079       /*
1080        * Find closing brace
1081        */
1082       char *br_p = strchr(cp, '}');
1083       int len;
1084 
1085       /*
1086        * Check we found it
1087        */
1088       if (!br_p) {
1089 	/*
1090 	 * Just give up
1091 	 */
1092 	plog(XLOG_USER, "No closing '}' in \"%s\"", opt);
1093 	goto out;
1094       }
1095       len = br_p - cp;
1096 
1097       /*
1098        * Figure out which part of the variable to grab.
1099        */
1100       if (*cp == '/') {
1101 	/*
1102 	 * Just take the last component
1103 	 */
1104 	todo = E_File;
1105 	cp++;
1106 	--len;
1107       } else if (*(br_p-1) == '/') {
1108 	/*
1109 	 * Take all but the last component
1110 	 */
1111 	todo = E_Dir;
1112 	--len;
1113       } else if (*cp == '.') {
1114 	/*
1115 	 * Take domain name
1116 	 */
1117 	todo = E_Domain;
1118 	cp++;
1119 	--len;
1120       } else if (*(br_p-1) == '.') {
1121 	/*
1122 	 * Take host name
1123 	 */
1124 	todo = E_Host;
1125 	--len;
1126       } else {
1127 	/*
1128 	 * Take the whole lot
1129 	 */
1130 	todo = E_All;
1131       }
1132 
1133       /*
1134        * Truncate if too long.  Since it won't
1135        * match anyway it doesn't matter that
1136        * it has been cut short.
1137        */
1138       if (len > NLEN)
1139 	len = NLEN;
1140 
1141       /*
1142        * Put the string into another buffer so
1143        * we can do comparisons.
1144        *
1145        * We use strncpy here (not xstrlcpy) because the dest is meant
1146        * to be truncated and we don't want to log it as an error.  The
1147        * use of the BUFSPACE macro above guarantees the safe use of
1148        * strncpy with nbuf.
1149        */
1150       strncpy(nbuf, cp, len);
1151       nbuf[len] = '\0';
1152 
1153       /*
1154        * Advance cp
1155        */
1156       cp = br_p + 1;
1157 
1158       /*
1159        * Search the option array
1160        */
1161       for (op = opt_fields; op->name; op++) {
1162 	/*
1163 	 * Check for match
1164 	 */
1165 	if (len == op->nlen && STREQ(op->name, nbuf)) {
1166 	  char xbuf[NLEN + 3];
1167 	  char *val;
1168 	  /*
1169 	   * Found expansion.  Copy
1170 	   * the correct value field.
1171 	   */
1172 	  if (!(!op->sel_p == !sel_p)) {
1173 	    /*
1174 	     * Copy the string across unexpanded
1175 	     */
1176 	    xsnprintf(xbuf, sizeof(xbuf), "${%s%s%s}",
1177 		      todo == E_File ? "/" :
1178 		      todo == E_Domain ? "." : "",
1179 		      nbuf,
1180 		      todo == E_Dir ? "/" :
1181 		      todo == E_Host ? "." : "");
1182 	    val = xbuf;
1183 	    /*
1184 	     * Make sure expansion doesn't
1185 	     * munge the value!
1186 	     */
1187 	    todo = E_All;
1188 	  } else if (op->sel_p) {
1189 	    val = *op->sel_p;
1190 	  } else {
1191 	    val = *op->optp;
1192 	  }
1193 
1194 	  if (val) {
1195 	    /*
1196 	     * Do expansion:
1197 	     * ${/var} means take just the last part
1198 	     * ${var/} means take all but the last part
1199 	     * ${.var} means take all but first part
1200 	     * ${var.} means take just the first part
1201 	     * ${var} means take the whole lot
1202 	     */
1203 	    int vlen = strlen(val);
1204 	    char *vptr = val;
1205 	    switch (todo) {
1206 	    case E_Dir:
1207 	      vptr = strrchr(val, '/');
1208 	      if (vptr)
1209 		vlen = vptr - val;
1210 	      vptr = val;
1211 	      break;
1212 	    case E_File:
1213 	      vptr = strrchr(val, '/');
1214 	      if (vptr) {
1215 		vptr++;
1216 		vlen = strlen(vptr);
1217 	      } else
1218 		vptr = val;
1219 	      break;
1220 	    case E_Domain:
1221 	      vptr = strchr(val, '.');
1222 	      if (vptr) {
1223 		vptr++;
1224 		vlen = strlen(vptr);
1225 	      } else {
1226 		vptr = "";
1227 		vlen = 0;
1228 	      }
1229 	      break;
1230 	    case E_Host:
1231 	      vptr = strchr(val, '.');
1232 	      if (vptr)
1233 		vlen = vptr - val;
1234 	      vptr = val;
1235 	      break;
1236 	    case E_All:
1237 	      break;
1238 	    }
1239 
1240 	    if (BUFSPACE(ep, vlen+1)) {
1241 	      xstrlcpy(ep, vptr, vlen+1);
1242 	      ep += vlen;
1243 	    } else {
1244 	      plog(XLOG_ERROR, EXPAND_ERROR, opt);
1245 	      goto out;
1246 	    }
1247 	  }
1248 	  /*
1249 	   * Done with this variable
1250 	   */
1251 	  break;
1252 	}
1253       }
1254 
1255       /*
1256        * Check that the search was successful
1257        */
1258       if (!op->name) {
1259 	/*
1260 	 * If it wasn't then scan the
1261 	 * environment for that name
1262 	 * and use any value found
1263 	 */
1264 	char *env = getenv(nbuf);
1265 
1266 	if (env) {
1267 	  int vlen = strlen(env);
1268 
1269 	  if (BUFSPACE(ep, vlen+1)) {
1270 	    xstrlcpy(ep, env, vlen+1);
1271 	    ep += vlen;
1272 	  } else {
1273 	    plog(XLOG_ERROR, EXPAND_ERROR, opt);
1274 	    goto out;
1275 	  }
1276 	  if (amuDebug(D_STR))
1277 	    plog(XLOG_DEBUG, "Environment gave \"%s\" -> \"%s\"", nbuf, env);
1278 	} else {
1279 	  plog(XLOG_USER, "Unknown sequence \"${%s}\"", nbuf);
1280 	}
1281       }
1282     } else {
1283       /*
1284        * Error, error
1285        */
1286       plog(XLOG_USER, "Unknown $ sequence in \"%s\"", opt);
1287     }
1288   }
1289 
1290 out:
1291   /*
1292    * Handle common case - no expansion
1293    */
1294   if (cp == opt) {
1295     opt = strdup(cp);
1296   } else {
1297     /*
1298      * Finish off the expansion
1299      */
1300     int vlen = strlen(cp);
1301     if (BUFSPACE(ep, vlen+1)) {
1302       xstrlcpy(ep, cp, vlen+1);
1303       /* ep += vlen; */
1304     } else {
1305       plog(XLOG_ERROR, EXPAND_ERROR, opt);
1306     }
1307 
1308     /*
1309      * Save the expansion
1310      */
1311     opt = strdup(expbuf);
1312   }
1313 
1314   normalize_slash(opt);
1315 
1316   if (amuDebug(D_STR)) {
1317     plog(XLOG_DEBUG, "Expansion of \"%s\"...", cp_orig);
1318     plog(XLOG_DEBUG, "......... is \"%s\"", opt);
1319   }
1320   return opt;
1321 }
1322 
1323 
1324 /*
1325  * Wrapper for expand_op
1326  */
1327 static void
expand_opts(opt_apply * p,int sel_p)1328 expand_opts(opt_apply *p, int sel_p)
1329 {
1330   if (*p->opt) {
1331     *p->opt = expand_op(*p->opt, sel_p);
1332   } else if (p->val) {
1333     /*
1334      * Do double expansion, remembering
1335      * to free the string from the first
1336      * expansion...
1337      */
1338     char *s = expand_op(p->val, TRUE);
1339     *p->opt = expand_op(s, sel_p);
1340     XFREE(s);
1341   }
1342 }
1343 
1344 
1345 /*
1346  * Apply a function to a list of options
1347  */
1348 static void
apply_opts(void (* op)(opt_apply *,int),opt_apply ppp[],int b)1349 apply_opts(void (*op) (opt_apply *, int), opt_apply ppp[], int b)
1350 {
1351   opt_apply *pp;
1352 
1353   for (pp = ppp; pp->opt; pp++)
1354     (*op) (pp, b);
1355 }
1356 
1357 
1358 /*
1359  * Free the option table
1360  */
1361 void
free_opts(am_opts * fo)1362 free_opts(am_opts *fo)
1363 {
1364   /*
1365    * Copy in the structure we are playing with
1366    */
1367   fs_static = *fo;
1368 
1369   /*
1370    * Free previously allocated memory
1371    */
1372   apply_opts(free_op, to_free, FALSE);
1373 }
1374 
1375 
1376 /*
1377  * Expand selectors (variables that cannot be assigned to or overridden)
1378  */
1379 char *
expand_selectors(char * key)1380 expand_selectors(char *key)
1381 {
1382   return expand_op(key, TRUE);
1383 }
1384 
1385 
1386 /*
1387  * Expand options (i.e. non-selectors, see above for definition)
1388  */
1389 static inline char *
expand_options(char * key)1390 expand_options(char *key)
1391 {
1392   return expand_op(key, FALSE);
1393 }
1394 
1395 
1396 /*
1397  * Remove trailing /'s from a string
1398  * unless the string is a single / (Steven Glassman)
1399  * or unless it is two slashes // (Kevin D. Bond)
1400  * or unless amd.conf says not to touch slashes.
1401  */
1402 void
deslashify(char * s)1403 deslashify(char *s)
1404 {
1405   if (!(gopt.flags & CFM_NORMALIZE_SLASHES))
1406     return;
1407 
1408   if (s && *s) {
1409     char *sl = s + strlen(s);
1410 
1411     while (*--sl == '/' && sl > s)
1412       *sl = '\0';
1413   }
1414 }
1415 
1416 
1417 int
eval_fs_opts(am_opts * fo,char * opts,char * g_opts,char * path,char * key,char * map)1418 eval_fs_opts(am_opts *fo, char *opts, char *g_opts, char *path, char *key, char *map)
1419 {
1420   int ok = TRUE;
1421 
1422   free_opts(fo);
1423 
1424   /*
1425    * Clear out the option table
1426    */
1427   memset((voidp) &fs_static, 0, sizeof(fs_static));
1428   memset((voidp) vars, 0, sizeof(vars));
1429   memset((voidp) fo, 0, sizeof(*fo));
1430 
1431   /* set hostname */
1432   opt_host = (char *) am_get_hostname();
1433 
1434   /*
1435    * Set key, map & path before expansion
1436    */
1437   opt_key = key;
1438   opt_map = map;
1439   opt_path = path;
1440 
1441   opt_dkey = strchr(key, '.');
1442   if (!opt_dkey) {
1443     opt_dkey = NullStr;
1444     opt_keyd = key;
1445   } else {
1446     opt_keyd = strnsave(key, opt_dkey - key);
1447     opt_dkey++;
1448     if (*opt_dkey == '\0')	/* check for 'host.' */
1449       opt_dkey = NullStr;
1450   }
1451 
1452   /*
1453    * Expand global options
1454    */
1455   fs_static.fs_glob = expand_selectors(g_opts);
1456 
1457   /*
1458    * Expand local options
1459    */
1460   fs_static.fs_local = expand_selectors(opts);
1461 
1462   /* break global options into fs_static fields */
1463   if ((ok = split_opts(fs_static.fs_glob, key))) {
1464     dlog("global split_opts ok");
1465     /*
1466      * evaluate local selectors
1467      */
1468     if ((ok = eval_selectors(fs_static.fs_local, key))) {
1469       dlog("local eval_selectors ok");
1470       /* if the local selectors matched, then do the local overrides */
1471       ok = split_opts(fs_static.fs_local, key);
1472       if (ok)
1473 	dlog("local split_opts ok");
1474     }
1475   }
1476 
1477   /*
1478    * Normalize remote host name.
1479    * 1.  Expand variables
1480    * 2.  Normalize relative to host tables
1481    * 3.  Strip local domains from the remote host
1482    *     name before using it in other expansions.
1483    *     This makes mount point names and other things
1484    *     much shorter, while allowing cross domain
1485    *     sharing of mount maps.
1486    */
1487   apply_opts(expand_opts, rhost_expansion, FALSE);
1488   if (ok && fs_static.opt_rhost && *fs_static.opt_rhost)
1489     host_normalize(&fs_static.opt_rhost);
1490 
1491   /*
1492    * Macro expand the options.
1493    * Do this regardless of whether we are accepting
1494    * this mount - otherwise nasty things happen
1495    * with memory allocation.
1496    */
1497   apply_opts(expand_opts, expansions, FALSE);
1498 
1499   /*
1500    * Strip trailing slashes from local pathname...
1501    */
1502   deslashify(fs_static.opt_fs);
1503 
1504   /*
1505    * ok... copy the data back out.
1506    */
1507   *fo = fs_static;
1508 
1509   /*
1510    * Clear defined options
1511    */
1512   if (opt_keyd != key && opt_keyd != nullstr)
1513     XFREE(opt_keyd);
1514   opt_keyd = nullstr;
1515   opt_dkey = NullStr;
1516   opt_key = opt_map = opt_path = nullstr;
1517 
1518   return ok;
1519 }
1520