c4f2d992 |
1 | /* -*-c-*- |
2 | * |
dd9ab078 |
3 | * $Id: class.c,v 1.8 1998/06/08 11:20:36 mdw Exp $ |
c4f2d992 |
4 | * |
5 | * Handling classes of things nicely |
6 | * |
c758e654 |
7 | * (c) 1998 EBI |
c4f2d992 |
8 | */ |
9 | |
03f996bd |
10 | /*----- Licensing notice --------------------------------------------------* |
c4f2d992 |
11 | * |
12 | * This file is part of `become' |
13 | * |
14 | * `Become' is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU General Public License as published by |
16 | * the Free Software Foundation; either version 2 of the License, or |
17 | * (at your option) any later version. |
18 | * |
19 | * `Become' is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU General Public License |
03f996bd |
25 | * along with `become'; if not, write to the Free Software Foundation, |
26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
c4f2d992 |
27 | */ |
28 | |
29 | /*----- Revision history --------------------------------------------------* |
30 | * |
31 | * $Log: class.c,v $ |
dd9ab078 |
32 | * Revision 1.8 1998/06/08 11:20:36 mdw |
33 | * (class__wildMatch) Fixed bug which overran pattern string, spotted by |
34 | * Mark Rison. |
35 | * |
c758e654 |
36 | * Revision 1.7 1998/01/12 16:45:50 mdw |
37 | * Fix copyright date. |
38 | * |
39 | * Revision 1.6 1997/09/17 10:14:56 mdw |
50a87c1f |
40 | * Complete rewrite to support class trees. Makes the behaviour of the set |
41 | * operators much more logical. |
42 | * |
43 | * Revision 1.5 1997/08/20 16:16:13 mdw |
51cf22e0 |
44 | * Patch memory leak. Don't try to trace when tracing's turned off. |
45 | * |
4f67acfa |
46 | * Revision 1.4 1997/08/07 09:56:37 mdw |
47 | * (Log entry for previous version is bogus.) Minor changes to host |
48 | * checking code. |
607937a4 |
49 | * |
03f996bd |
50 | * Revision 1.2 1997/08/04 10:24:21 mdw |
51 | * Sources placed under CVS control. |
52 | * |
53 | * Revision 1.1 1997/07/21 13:47:52 mdw |
c4f2d992 |
54 | * Initial revision |
55 | * |
56 | */ |
57 | |
58 | /*----- Header files ------------------------------------------------------*/ |
59 | |
60 | /* --- ANSI headers --- */ |
61 | |
62 | #include <stdio.h> |
63 | #include <stdlib.h> |
64 | #include <string.h> |
65 | |
66 | /* --- Unix headers --- */ |
67 | |
68 | #include <sys/types.h> |
69 | #include <sys/socket.h> |
70 | |
71 | #include <netinet/in.h> |
72 | |
73 | #include <arpa/inet.h> |
74 | |
75 | #include <netdb.h> |
76 | |
77 | /* --- Local headers --- */ |
78 | |
03f996bd |
79 | #include "become.h" |
c4f2d992 |
80 | #include "class.h" |
c4f2d992 |
81 | #include "sym.h" |
82 | #include "utils.h" |
83 | |
84 | /*----- Global variables --------------------------------------------------*/ |
85 | |
50a87c1f |
86 | static class_node class__all = { clType_all | clNode_any, -1, { 0 }}; |
87 | class_node *class_all = &class__all; |
88 | |
89 | static class_node class__none = { clType_all | clNode_any, -1, { 0 }}; |
90 | class_node *class_none = &class__none; |
c4f2d992 |
91 | |
92 | /*----- Wildcard matching -------------------------------------------------*/ |
93 | |
94 | /* --- @class__wildMatch@ --- * |
95 | * |
96 | * Arguments: @const char *pat@ = pointer to pattern string |
97 | * @const char *p@ = pointer to target string |
98 | * |
99 | * Returns: Zero if no match, nonzero if match. |
100 | * |
101 | * Use: Wildcard-matches the pattern against the target string. |
102 | */ |
103 | |
104 | static int class__wildMatch(const char *pat, const char *p) |
105 | { |
106 | for (;;) { |
107 | if (*pat == 0 && *p == 0) |
108 | return (42); /* For sadism's sake */ |
109 | else if (*pat == '*') { |
110 | while (*pat == '*') |
111 | pat++; |
dd9ab078 |
112 | if (!*pat) |
113 | return (58); |
c4f2d992 |
114 | do { |
115 | if (class__wildMatch(pat, p)) |
116 | return (27); /* Nyahaha */ |
117 | p++; |
118 | } while (*p); |
dd9ab078 |
119 | return (0); |
c4f2d992 |
120 | } else if (*pat == '?' || *pat == *p) |
121 | p++, pat++; |
122 | else |
123 | return (0); |
124 | } |
125 | } |
126 | |
50a87c1f |
127 | /*----- Creating new class nodes ------------------------------------------*/ |
128 | |
129 | /* --- @class_fromString@ --- * |
130 | * |
131 | * Arguments: @unsigned type@ = a type field |
132 | * @const char *s@ = pointer to string to copy |
133 | * |
134 | * Returns: A pointer to a class node containing that string, typed to |
135 | * be the right thing. |
136 | * |
137 | * Use: Given a string, wrap a class node around it. The node has |
138 | * one reference (the one you get returned). The string is |
139 | * copied, so you can get rid of your original one if you like. |
140 | */ |
141 | |
142 | class_node *class_fromString(unsigned type, const char *s) |
143 | { |
144 | class_node *c = xmalloc(sizeof(*c)); |
145 | c->type = type | clNode_immed; |
146 | if (s[strcspn(s, "*?")] == 0) |
147 | c->type |= clFlag_friendly; |
148 | c->ref = 1; |
149 | c->v.s = xstrdup(s); |
150 | return (c); |
151 | } |
c4f2d992 |
152 | |
50a87c1f |
153 | /* --- @class_fromUser@ --- * |
c4f2d992 |
154 | * |
50a87c1f |
155 | * Arguments: @unsigned type@ = a type field |
156 | * @uid_t u@ = a user-id number |
c4f2d992 |
157 | * |
50a87c1f |
158 | * Returns: A pointer to a class node containing the uid, typed to be |
159 | * the thing you asked for. Hopefully this will be |
160 | * @clType_user@. |
c4f2d992 |
161 | * |
50a87c1f |
162 | * Use: Given a uid, wrap a class node around it. |
c4f2d992 |
163 | */ |
164 | |
50a87c1f |
165 | class_node *class_fromUser(unsigned type, uid_t u) |
c4f2d992 |
166 | { |
50a87c1f |
167 | class_node *c = xmalloc(sizeof(*c)); |
168 | c->type = type | clNode_immed | clFlag_friendly; |
c4f2d992 |
169 | c->ref = 1; |
50a87c1f |
170 | c->v.u = u; |
c4f2d992 |
171 | return (c); |
172 | } |
173 | |
50a87c1f |
174 | /*----- Reference counter tricks ------------------------------------------*/ |
175 | |
c4f2d992 |
176 | /* --- @class_inc@ --- * |
177 | * |
50a87c1f |
178 | * Arguments: @class_node *c@ = pointer to a class block |
c4f2d992 |
179 | * |
180 | * Returns: --- |
181 | * |
182 | * Use: Adds a reference to the class definition. |
183 | */ |
184 | |
50a87c1f |
185 | void class_inc(class_node *c) |
c4f2d992 |
186 | { |
50a87c1f |
187 | if (c != class_all && c != class_none) |
c4f2d992 |
188 | c->ref++; |
189 | } |
190 | |
191 | /* --- @class_dec@ --- * |
192 | * |
50a87c1f |
193 | * Arguments: @class_node *c@ = pointer to a class block |
c4f2d992 |
194 | * |
195 | * Returns: --- |
196 | * |
197 | * Use: Removes a reference to a class block. |
198 | */ |
199 | |
50a87c1f |
200 | void class_dec(class_node *c) |
c4f2d992 |
201 | { |
50a87c1f |
202 | class_node *cc; |
203 | |
204 | for (cc = 0; c; c = cc, cc = 0) { |
205 | if (c == class_all || c == class_none || --c->ref) |
206 | continue; |
207 | switch (c->type & clNode_mask) { |
208 | case clNode_any: |
209 | /* Nothing to do */ |
210 | break; |
211 | case clNode_immed: |
212 | if (c->type & (clType_host | clType_command)) |
213 | free(c->v.s); |
214 | break; |
215 | case clNode_hash: |
216 | sym_destroyTable(&c->v.t); |
217 | break; |
218 | case clNode_union: |
219 | case clNode_diff: |
220 | case clNode_isect: |
221 | class_dec(c->v.c.l); |
222 | cc = c->v.c.r; |
223 | break; |
224 | } |
c4f2d992 |
225 | free(c); |
226 | } |
227 | } |
228 | |
50a87c1f |
229 | /* --- @class_mod@ --- * |
c4f2d992 |
230 | * |
50a87c1f |
231 | * Arguments: @class_node *c@ = pointer to a class node |
c4f2d992 |
232 | * |
50a87c1f |
233 | * Returns: A pointer to a class node, maybe the same one, maybe not, |
234 | * with a reference count of 1, containing the same data. |
c4f2d992 |
235 | * |
50a87c1f |
236 | * Use: Gives you a node which you can modify. Don't call this |
237 | * for @class_all@ or @class_none@. |
c4f2d992 |
238 | */ |
239 | |
50a87c1f |
240 | class_node *class_mod(class_node *c) |
c4f2d992 |
241 | { |
50a87c1f |
242 | class_node *cc; |
243 | |
244 | if (c->ref == 1) |
245 | return (c); |
246 | |
247 | cc = xmalloc(sizeof(*cc)); |
248 | cc->type = c->type; |
249 | cc->ref = 1; |
250 | switch (c->type & clNode_mask) { |
251 | case clNode_any: |
252 | die("internal error: class_mod called on non-modifiable class node"); |
253 | break; |
254 | |
255 | case clNode_immed: |
256 | if (c->type & clType_user) |
257 | cc->v.u = c->v.u; |
258 | else |
259 | cc->v.s = xstrdup(c->v.s); |
260 | break; |
261 | |
262 | case clNode_hash: { |
263 | sym_iter i; |
264 | sym_base *b; |
265 | |
266 | sym_createTable(&cc->v.t); |
267 | for (sym_createIter(&i, &c->v.t); (b = sym_next(&i)) != 0; ) |
268 | sym_find(&cc->v.t, b->name, b->len, sizeof(sym_base), 0); |
269 | } break; |
270 | |
271 | case clNode_union: |
272 | case clNode_diff: |
273 | case clNode_isect: |
274 | cc->v.c.l = c->v.c.l; |
275 | cc->v.c.r = c->v.c.r; |
276 | class_inc(cc->v.c.l); |
277 | class_inc(cc->v.c.r); |
278 | break; |
03f996bd |
279 | } |
50a87c1f |
280 | |
281 | class_dec(c); |
282 | return (cc); |
c4f2d992 |
283 | } |
284 | |
50a87c1f |
285 | /*----- Some weirder operations on classes --------------------------------*/ |
286 | |
287 | /* --- @class__hashify@ --- * |
c4f2d992 |
288 | * |
50a87c1f |
289 | * Arguments: @class_node *c@ = pointer to a node |
c4f2d992 |
290 | * |
50a87c1f |
291 | * Returns: A pointer to a hash node containing the node's value. |
c4f2d992 |
292 | * |
50a87c1f |
293 | * Use: The original node must have type `immediate', and it must |
294 | * be friendly. The old reference is discarded -- you get this |
295 | * one instead. |
c4f2d992 |
296 | */ |
297 | |
50a87c1f |
298 | static class_node *class__hashify(class_node *c) |
c4f2d992 |
299 | { |
50a87c1f |
300 | /* --- Some sanity checking --- */ |
c4f2d992 |
301 | |
50a87c1f |
302 | if (~c->type & clFlag_friendly) |
303 | die("internal error: class__hashify can't hashify unfriendly nodes"); |
304 | if ((c->type & clNode_mask) != clNode_immed) |
305 | die("internal error: class__hashify can't hashify non-immediate nodes"); |
306 | |
307 | /* --- Split off a private copy of the node --- */ |
308 | |
309 | c = class_mod(c); |
310 | |
311 | c->type = (c->type & clType_mask) | clNode_hash | clFlag_friendly; |
312 | |
313 | if (c->type & clType_user) { |
314 | uid_t u = c->v.u; |
315 | sym_createTable(&c->v.t); |
316 | sym_find(&c->v.t, (char *)&u, sizeof(u), sizeof(sym_base), 0); |
03f996bd |
317 | } else { |
50a87c1f |
318 | char *s = c->v.s; |
319 | sym_createTable(&c->v.t); |
320 | sym_find(&c->v.t, s, -1, sizeof(sym_base), 0); |
321 | free(s); |
c4f2d992 |
322 | } |
50a87c1f |
323 | |
324 | return (c); |
c4f2d992 |
325 | } |
326 | |
50a87c1f |
327 | /*----- Arithmetic on classes ---------------------------------------------*/ |
328 | |
329 | /* --- @class__binop@ --- * |
330 | * |
331 | * Arguments: @class_node *l@ = left argument |
332 | * @class_node *r@ = right argument |
333 | * @unsigned op@ = the binop code |
c4f2d992 |
334 | * |
50a87c1f |
335 | * Returns: A class node representing the result of a binary operation |
336 | * upon two classes. |
c4f2d992 |
337 | * |
50a87c1f |
338 | * Use: Performs a binary operation on classes. If the types don't |
339 | * match, then a null pointer is returned. Both @l@ and @r@ |
340 | * may be modified, and will be decremented before they get |
341 | * returned to you. If you don't want that to happen, ensure |
342 | * that you've claimed a reference to the original versions. |
c4f2d992 |
343 | * |
50a87c1f |
344 | * If both nodes are `friendly' (see below), then an attempt is |
345 | * made to combine them sensibly using a hashtable. |
346 | * |
347 | * If one or both nodes is/are unfriendly, a binop node is |
348 | * created with type @op@ to allow the matcher to decide on |
349 | * membership appropriately at match time. |
350 | * |
351 | * A friendly node is one which can be placed in a hash table to |
352 | * speed up searching. It's friendly, because it doesn't mind |
353 | * living with other nodes. Uid numbers are friendly. |
354 | * Wildcarded strings aren't. Hashtables are trivially |
355 | * friendly. |
c4f2d992 |
356 | */ |
357 | |
50a87c1f |
358 | class_node *class__binop(class_node *l, class_node *r, int op) |
c4f2d992 |
359 | { |
50a87c1f |
360 | unsigned type = l->type & r->type & clType_mask; |
361 | unsigned lnode = l->type & clNode_mask, rnode = r->type & clNode_mask; |
362 | |
363 | /* --- Check for compatible types --- */ |
c4f2d992 |
364 | |
50a87c1f |
365 | if (!type) { |
366 | class_dec(l); |
367 | class_dec(r); |
c4f2d992 |
368 | return (0); |
50a87c1f |
369 | } |
c4f2d992 |
370 | |
50a87c1f |
371 | /* --- Handle `friendly' nodes --- */ |
c4f2d992 |
372 | |
50a87c1f |
373 | if ((l->type & r->type & clFlag_friendly)) { |
374 | |
375 | /* --- Consider promoting an item to a hash --- * |
376 | * |
377 | * If both are immediate nodes, and they're both `friendly', we can |
378 | * profitably hash them together. |
379 | * |
380 | * Life gets complicated when we do subtraction, because it's not |
381 | * commutative. In this case, I have to promote the left operand anyway. |
382 | */ |
383 | |
384 | if (lnode == clNode_immed && |
385 | (rnode == clNode_immed || op == clNode_diff)) { |
386 | |
387 | /* --- Quick check for triviality --- * |
388 | * |
389 | * There are some more short-cuts I can employ if the values are |
390 | * the same. |
391 | */ |
392 | |
393 | if (rnode == clNode_immed) { |
394 | |
395 | /* --- See whether the two items are equal --- */ |
396 | |
397 | int eq = (type & clType_user ? |
398 | l->v.u == r->v.u : strcmp(l->v.s, r->v.s) == 0); |
399 | |
400 | /* --- Now do something appropriate --- */ |
401 | |
402 | switch (op) { |
403 | case clNode_union: |
404 | if (eq) { |
405 | class_dec(r); |
406 | return (l); |
407 | } |
408 | break; |
409 | case clNode_diff: |
410 | if (eq) { |
411 | class_dec(l); |
412 | class_dec(r); |
413 | return (class_none); |
414 | } |
415 | break; |
416 | case clNode_isect: |
417 | if (eq) { |
418 | class_dec(r); |
419 | return (l); |
420 | } else { |
421 | class_dec(l); |
422 | class_dec(r); |
423 | return (class_none); |
424 | } |
425 | break; |
426 | } |
427 | } |
428 | |
429 | /* --- Turn @l@ into a hash containing itself --- */ |
430 | |
431 | l = class__hashify(l); |
432 | lnode = clNode_hash; |
03f996bd |
433 | } |
607937a4 |
434 | |
50a87c1f |
435 | /* --- Otherwise, make @l@ the hash --- * |
436 | * |
437 | * Both @l@ and @r@ are friendly. Since they're not both immediates, |
438 | * one must be a hash. |
439 | */ |
c4f2d992 |
440 | |
50a87c1f |
441 | else if ((l->type & clNode_mask) == clNode_immed) { |
442 | class_node *tn; |
443 | unsigned tt; |
444 | |
445 | tn = l, l = r, r = tn; |
446 | tt = lnode, lnode = rnode, rnode = tt; |
447 | } |
448 | |
449 | /* --- Now merge @r@ with @l@ --- */ |
450 | |
451 | l = class_mod(l); |
452 | |
453 | switch (op) { |
454 | |
455 | /* --- The union operation isn't hard --- */ |
456 | |
457 | case clNode_union: |
458 | if (rnode == clNode_immed) { |
459 | if (type & clType_user) { |
460 | sym_find(&l->v.t, (char *)&r->v.u, |
461 | sizeof(r->v.u), sizeof(sym_base), 0); |
462 | } else |
463 | sym_find(&l->v.t, r->v.s, -1, sizeof(sym_base), 0); |
464 | } else { |
465 | sym_iter i; |
466 | sym_base *b; |
467 | |
468 | for (sym_createIter(&i, &r->v.t); (b = sym_next(&i)) != 0; ) |
469 | sym_find(&l->v.t, b->name, b->len, sizeof(sym_base), 0); |
470 | } |
471 | break; |
472 | |
473 | /* --- Set difference is similar in spirit --- */ |
474 | |
475 | case clNode_diff: |
476 | if (rnode == clNode_immed) { |
477 | sym_base *f; |
478 | |
479 | if (type & clType_user) |
480 | f = sym_find(&l->v.t, (char *)&r->v.u, sizeof(r->v.u), 0, 0); |
481 | else |
482 | f = sym_find(&l->v.t, r->v.s, -1, 0, 0); |
483 | if (f) |
484 | sym_remove(&l->v.t, f); |
485 | } else { |
486 | sym_iter i; |
487 | sym_base *b, *f; |
488 | |
489 | for (sym_createIter(&i, &r->v.t); (b = sym_next(&i)) != 0; ) { |
490 | if ((f = sym_find(&l->v.t, b->name, b->len, 0, 0)) != 0) |
491 | sym_remove(&l->v.t, f); |
492 | } |
493 | } |
494 | break; |
495 | |
496 | /* --- Intersection is wild and wacky --- */ |
497 | |
498 | case clNode_isect: |
499 | if (rnode == clNode_immed) { |
500 | sym_base *f; |
501 | |
502 | if (type & clType_user) |
503 | f = sym_find(&l->v.t, (char *)&r->v.u, sizeof(r->v.u), 0, 0); |
504 | else |
505 | f = sym_find(&l->v.t, r->v.s, -1, 0, 0); |
506 | if (f) { |
507 | class_dec(l); |
508 | return (r); |
509 | } else { |
510 | class_dec(l); |
511 | class_dec(r); |
512 | return (class_none); |
513 | } |
514 | } else { |
515 | sym_iter i; |
516 | sym_base *b; |
517 | |
518 | for (sym_createIter(&i, &l->v.t); (b = sym_next(&i)) != 0; ) { |
519 | if (!sym_find(&r->v.t, b->name, b->len, 0, 0)) |
520 | sym_remove(&l->v.t, b); |
521 | } |
522 | } |
523 | break; |
524 | } |
525 | |
526 | /* --- Now trim the @l@ table to size --- * |
c4f2d992 |
527 | * |
50a87c1f |
528 | * It may have lost a load of elements. Maybe it can be represented |
529 | * better as an immediate or even as @class_none@. |
c4f2d992 |
530 | */ |
531 | |
50a87c1f |
532 | { |
533 | sym_iter i; |
534 | sym_base *b; |
c4f2d992 |
535 | |
50a87c1f |
536 | class_dec(r); |
c4f2d992 |
537 | |
50a87c1f |
538 | sym_createIter(&i, &l->v.t); |
539 | if ((b = sym_next(&i)) == 0) { |
540 | class_dec(l); |
541 | return (class_none); |
03f996bd |
542 | } |
50a87c1f |
543 | if (!sym_next(&i)) { |
544 | if (type & clType_user) { |
545 | uid_t u = *(uid_t *)b->name; |
546 | sym_destroyTable(&l->v.t); |
547 | l->type = (l->type & ~clNode_mask) | clNode_immed; |
548 | l->v.u = u; |
549 | } else { |
550 | char *s = xstrdup(b->name); |
551 | sym_destroyTable(&l->v.t); |
552 | l->type = (l->type & ~clNode_mask) | clNode_immed; |
553 | l->v.s = s; |
554 | } |
555 | } |
556 | } |
557 | |
558 | /* --- Done --- */ |
559 | |
560 | return (l); |
561 | } |
562 | |
563 | /* --- Unfriendly nodes --- * |
564 | * |
565 | * Create a binop node and return that. If @l@ is a binop node, and @r@ |
566 | * isn't, and the operation isn't set difference (i.e., it's commutative) |
567 | * then swap the two over to lessen the depth of recursion later. |
568 | */ |
569 | |
570 | else { |
571 | class_node *c = xmalloc(sizeof(*c)); |
572 | |
573 | c->type = type | op; |
574 | c->ref = 1; |
575 | if (lnode >= clNode_binop && rnode < clNode_binop && op != clNode_diff) { |
576 | c->v.c.l = r; |
577 | c->v.c.r = l; |
578 | } else { |
579 | c->v.c.l = l; |
580 | c->v.c.r = r; |
581 | } |
582 | return (c); |
583 | } |
584 | } |
585 | |
586 | /* --- @class_union@ --- * |
587 | * |
588 | * Arguments: @class_node *l@ = left argument |
589 | * @class_node *r@ = right argument |
590 | * |
591 | * Returns: A class node representing the union of the two classes. |
592 | * |
593 | * Use: Performs the union operation on classes. If the types don't |
594 | * match, then a null pointer is returned. Both @l@ and @r@ |
595 | * may be modified, and will be decremented before they get |
596 | * returned to you. If you don't want that to happen, ensure |
597 | * that you've claimed a reference to the original versions. |
598 | */ |
599 | |
600 | class_node *class_union(class_node *l, class_node *r) |
601 | { |
602 | /* --- Check for the really simple cases --- */ |
603 | |
604 | if (l == class_all || r == class_all) { |
605 | class_dec(l); |
606 | class_dec(r); |
607 | return (class_all); |
608 | } |
609 | |
610 | if (l == class_none) |
611 | return (r); |
612 | if (r == class_none) |
613 | return (l); |
c4f2d992 |
614 | |
50a87c1f |
615 | /* --- Do the job --- */ |
616 | |
617 | return (class__binop(l, r, clNode_union)); |
618 | } |
619 | |
620 | /* --- @class_diff@ --- * |
621 | * |
622 | * Arguments: @class_node *l@ = left argument |
623 | * @class_node *r@ = right argument |
624 | * |
625 | * Returns: A class node representing the difference of the two classes. |
626 | * |
627 | * Use: Performs the set difference operation on classes. If the |
628 | * types don't match, then a null pointer is returned. Both |
629 | * @l@ and @r@ may be modified, and will be decremented before |
630 | * they get returned to you. If you don't want that to happen, |
631 | * ensure that you've claimed a reference to the original |
632 | * versions. |
633 | */ |
634 | |
635 | class_node *class_diff(class_node *l, class_node *r) |
636 | { |
637 | /* --- Check for the really simple cases --- */ |
638 | |
639 | if (l == class_none || r == class_all) { |
640 | class_dec(l); |
641 | class_dec(r); |
642 | return (class_none); |
643 | } |
c4f2d992 |
644 | |
50a87c1f |
645 | if (r == class_none) |
646 | return (l); |
c4f2d992 |
647 | |
50a87c1f |
648 | /* --- Do the job --- */ |
649 | |
650 | return (class__binop(l, r, clNode_diff)); |
651 | } |
652 | |
653 | /* --- @class_isect@ --- * |
654 | * |
655 | * Arguments: @class_node *l@ = left argument |
656 | * @class_node *r@ = right argument |
657 | * |
658 | * Returns: A class node representing the intersection of the two |
659 | * classes. |
660 | * |
661 | * Use: Performs the intersecion operation on classes. If the types |
662 | * don't match, then a null pointer is returned. Both @l@ and |
663 | * @r@ may be modified, and will be decremented before they get |
664 | * returned to you. If you don't want that to happen, ensure |
665 | * that you've claimed a reference to the original versions. |
666 | */ |
667 | |
668 | class_node *class_isect(class_node *l, class_node *r) |
669 | { |
670 | /* --- Check for the really simple cases --- */ |
671 | |
672 | if (l == class_none || r == class_none) { |
673 | class_dec(l); |
674 | class_dec(r); |
675 | return (class_none); |
676 | } |
677 | |
678 | if (l == class_all) |
679 | return (r); |
680 | if (r == class_all) |
681 | return (l); |
682 | |
683 | /* --- Do the job --- */ |
684 | |
685 | return (class__binop(l, r, clNode_isect)); |
686 | } |
687 | |
688 | /*----- Building the predefined classes -----------------------------------*/ |
689 | |
690 | /* --- @class_addUser@ --- * |
691 | * |
692 | * Arguments: @class_node *c@ = pointer to a class node (may be null) |
693 | * @uid_t u@ = user id number |
694 | * |
695 | * Returns: Pointer to the combined node. |
696 | * |
697 | * Use: Adds a user to a node, maybe hashifying it. |
698 | */ |
699 | |
700 | class_node *class_addUser(class_node *c, uid_t u) |
701 | { |
702 | if (!c) |
703 | return (class_fromUser(clType_user, u)); |
704 | if ((c->type & clNode_mask) == clNode_immed) |
705 | c = class__hashify(c); |
706 | sym_find(&c->v.t, (char *)&u, sizeof(u), sizeof(sym_base), 0); |
707 | return (c); |
708 | } |
709 | |
710 | /* --- @class_addString@ --- * |
711 | * |
712 | * Arguments: @class_node *c@ = pointer to a class node (may be null) |
713 | * @const char *s@ = pointer to a string |
714 | * |
715 | * Returns: Pointer to the combined node. |
716 | * |
717 | * Use: Adds a user to a node, maybe hashifying it. |
718 | */ |
719 | |
720 | class_node *class_addString(class_node *c, const char *s) |
721 | { |
722 | class_node *n = class_fromString(clType_host, s); /* hack */ |
723 | if (c) |
724 | return (class_union(c, n)); |
725 | else |
726 | return (n); |
727 | } |
728 | |
729 | /*----- Matching functions ------------------------------------------------*/ |
730 | |
731 | /* --- @class_matchUser@ --- * |
732 | * |
733 | * Arguments: @class_node *c@ = pointer to root class node |
734 | * @uid_t u@ = user id number |
735 | * |
736 | * Returns: Nonzero if it matches, zero if it doesn't. |
737 | * |
738 | * Use: Determines whether a user is matched by a class. Assumes |
739 | * that the types are correct. |
740 | */ |
741 | |
742 | int class_matchUser(class_node *c, uid_t u) |
743 | { |
744 | class_node *cc; |
745 | |
746 | for (cc = 0; c; c = cc, cc = 0) { |
747 | if (c == class_none) |
748 | return (0); |
749 | if (c == class_all) |
750 | return (1); |
751 | switch (c->type & clNode_mask) { |
752 | case clNode_immed: |
753 | return (u == c->v.u); |
754 | break; |
755 | case clNode_hash: |
756 | return (sym_find(&c->v.t, (char *)&u, sizeof(u), 0, 0) != 0); |
757 | break; |
758 | case clNode_union: |
759 | if (class_matchUser(c->v.c.l, u)) |
c4f2d992 |
760 | return (1); |
50a87c1f |
761 | cc = c->v.c.r; |
762 | break; |
763 | case clNode_isect: |
764 | if (!class_matchUser(c->v.c.l, u)) |
765 | return (0); |
766 | cc = c->v.c.r; |
767 | break; |
768 | case clNode_diff: |
769 | return (class_matchUser(c->v.c.l, u) && |
770 | !class_matchUser(c->v.c.r, u)); |
771 | break; |
772 | } |
773 | } |
774 | |
775 | die("internal error: can't get here in class_matchUser"); |
776 | return (0); |
777 | } |
778 | |
779 | /* --- @class_matchCommand@ --- * |
780 | * |
781 | * Arguments: @class_node *c@ = pointer to root class node |
782 | * @const char *s@ = pointer to a string |
783 | * |
784 | * Returns: Nonzero if it matches, zero if it doesn't. |
785 | * |
786 | * Use: Determines whether a string is matched by a class. Assumes |
787 | * that the types are correct. |
788 | */ |
789 | |
790 | int class_matchCommand(class_node *c, const char *s) |
791 | { |
792 | class_node *cc; |
607937a4 |
793 | |
50a87c1f |
794 | for (cc = 0; c; c = cc, cc = 0) { |
795 | if (c == class_none) |
796 | return (0); |
797 | if (c == class_all) |
798 | return (1); |
799 | switch (c->type & clNode_mask) { |
800 | case clNode_immed: |
801 | return (class__wildMatch(c->v.s, s)); |
802 | break; |
803 | case clNode_hash: |
804 | return (sym_find(&c->v.t, s, -1, 0, 0) != 0); |
805 | break; |
806 | case clNode_union: |
807 | if (class_matchCommand(c->v.c.l, s)) |
808 | return (1); |
809 | cc = c->v.c.r; |
810 | break; |
811 | case clNode_isect: |
812 | if (!class_matchCommand(c->v.c.l, s)) |
813 | return (0); |
814 | cc = c->v.c.r; |
815 | break; |
816 | case clNode_diff: |
817 | return (class_matchCommand(c->v.c.l, s) && |
818 | !class_matchCommand(c->v.c.r, s)); |
819 | break; |
820 | } |
821 | } |
822 | |
823 | die("internal error: can't get here in class_matchCommand"); |
824 | return (0); |
825 | } |
826 | |
827 | /* --- @class_matchHost@ --- * |
828 | * |
829 | * Arguments: @class_node *c@ = pointer to root class node |
830 | * @struct in_addr a@ = IP address to match |
831 | * |
832 | * Returns: Nonzero if it matches, zero if it doesn't. |
833 | * |
834 | * Use: Determines whether a host matches a host class. Assumes |
835 | * that the types are correct. The actual mechanism is a bit |
836 | * odd here, but I think this is the Right Thing. At each stage |
837 | * I try to match %%@/all/%% of the possible names for the host. |
838 | * Thus host `splat' with address 1.2.3.4 would fail to match |
839 | * the class "1.2.*" - "splat". This seems to be what the |
840 | * author intuitively expects. It's just a bit weird. |
841 | */ |
842 | |
843 | static int class__doMatchHost(class_node *c, const char *ip, |
844 | const char *name, char **aliases) |
845 | { |
846 | class_node *cc; |
607937a4 |
847 | |
50a87c1f |
848 | for (cc = 0; c; c = cc, cc = 0) { |
849 | if (c == class_none) |
850 | return (0); |
851 | if (c == class_all) |
852 | return (1); |
853 | switch (c->type & clNode_mask) { |
854 | case clNode_immed: |
855 | if ((ip && class__wildMatch(c->v.s, ip)) || |
856 | (name && class__wildMatch(c->v.s, name))) |
857 | return (1); |
858 | if (aliases) for (; *aliases; aliases++) { |
859 | if (class__wildMatch(c->v.s, *aliases)) |
607937a4 |
860 | return (1); |
607937a4 |
861 | } |
50a87c1f |
862 | return (0); |
863 | break; |
864 | case clNode_hash: |
865 | if ((ip && sym_find(&c->v.t, ip, -1, 0, 0)) || |
866 | (name && sym_find(&c->v.t, name, -1, 0, 0))) |
867 | return (1); |
868 | if (aliases) for (; *aliases; aliases++) { |
869 | if (sym_find(&c->v.t, *aliases, -1, 0, 0)) |
870 | return (1); |
871 | } |
872 | return (0); |
873 | break; |
874 | case clNode_union: |
875 | if (class__doMatchHost(c->v.c.l, ip, name, aliases)) |
876 | return (1); |
877 | cc = c->v.c.r; |
878 | break; |
879 | case clNode_isect: |
880 | if (!class__doMatchHost(c->v.c.l, ip, name, aliases)) |
881 | return (0); |
882 | cc = c->v.c.r; |
883 | break; |
884 | case clNode_diff: |
885 | return (class__doMatchHost(c->v.c.l, ip, name, aliases) && |
886 | !class__doMatchHost(c->v.c.r, ip, name, aliases)); |
887 | break; |
c4f2d992 |
888 | } |
50a87c1f |
889 | } |
03f996bd |
890 | |
50a87c1f |
891 | die("internal error: can't get here in class_matchUser"); |
892 | return (0); |
893 | } |
894 | |
895 | int class_matchHost(class_node *c, struct in_addr a) |
896 | { |
897 | char *ip, *name, **aliases; |
898 | struct hostent *h; |
899 | |
900 | ip = inet_ntoa(a); |
901 | if ((h = gethostbyaddr((char *)&a, sizeof(a), AF_INET)) != 0) { |
902 | name = h->h_name; |
903 | aliases = h->h_aliases; |
904 | } else { |
905 | name = 0; |
906 | aliases = 0; |
c4f2d992 |
907 | } |
50a87c1f |
908 | |
909 | return (class__doMatchHost(c, ip, name, aliases)); |
c4f2d992 |
910 | } |
911 | |
50a87c1f |
912 | /*----- Debugging code ----------------------------------------------------*/ |
913 | |
c4f2d992 |
914 | /* --- @class_dump@ --- * |
915 | * |
50a87c1f |
916 | * Argumemnts: @class_node *c@ = pointer to root node |
917 | * @int indent@ = indent depth |
c4f2d992 |
918 | * |
919 | * Returns: --- |
920 | * |
50a87c1f |
921 | * Use: Dumps a class to the trace output. |
c4f2d992 |
922 | */ |
923 | |
50a87c1f |
924 | void class_dump(class_node *c, int indent) |
c4f2d992 |
925 | { |
51cf22e0 |
926 | #ifdef TRACING |
50a87c1f |
927 | |
928 | static char *types[] = { |
929 | "<duff>", |
930 | "user", |
931 | "command", |
932 | "<duff>", |
933 | "host" |
934 | }; |
935 | |
936 | static char *nodes[] = { |
937 | "<duff>", |
938 | "<magical>", |
939 | "immediate", |
940 | "hash", |
941 | "binop: union", |
942 | "binop: difference", |
943 | "binop: intersection" |
944 | }; |
945 | |
946 | /* --- Handle some magical cases --- */ |
947 | |
948 | if (c == class_all) { |
949 | trace(TRACE_RULE, "rule:%*s class ALL", indent * 2, ""); |
950 | return; |
951 | } |
952 | if (c == class_none) { |
953 | trace(TRACE_RULE, "rule:%*s class NONE", indent * 2, ""); |
954 | return; |
955 | } |
956 | |
957 | /* --- Dump basic type information --- */ |
958 | |
959 | trace(TRACE_RULE, "rule:%*s type == [%s], node type == [%s]%s", |
960 | indent * 2, "", |
961 | types[c->type & clType_mask], |
962 | nodes[(c->type & clNode_mask) >> 4], |
963 | (c->type & clFlag_friendly) ? " Friendly" : ""); |
964 | |
965 | /* --- Now trace the contents --- */ |
966 | |
967 | switch (c->type & clNode_mask) { |
968 | case clNode_immed: |
969 | if (c->type & clType_user) { |
970 | trace(TRACE_RULE, "rule:%*s user %lu", |
971 | indent * 2, "", (unsigned long)c->v.u); |
972 | } else |
973 | trace(TRACE_RULE, "rule:%*s `%s'", indent * 2, "", c->v.s); |
974 | break; |
975 | case clNode_hash: { |
976 | sym_iter i; |
977 | sym_base *b; |
978 | |
979 | for (sym_createIter(&i, &c->v.t); (b = sym_next(&i)) != 0; ) { |
980 | if (c->type & clType_user) { |
981 | trace(TRACE_RULE, "rule:%*s user %lu", |
982 | indent * 2, "", (unsigned long)*(uid_t *)b->name); |
983 | } else |
984 | trace(TRACE_RULE, "rule:%*s `%s'", indent * 2, "", b->name); |
c4f2d992 |
985 | } |
50a87c1f |
986 | } break; |
987 | case clNode_union: |
988 | case clNode_diff: |
989 | case clNode_isect: |
990 | class_dump(c->v.c.l, indent + 1); |
991 | class_dump(c->v.c.r, indent + 1); |
992 | break; |
c4f2d992 |
993 | } |
50a87c1f |
994 | |
51cf22e0 |
995 | #endif |
c4f2d992 |
996 | } |
997 | |
998 | /*----- That's all, folks -------------------------------------------------*/ |