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1ab84bf3 QY |
1 | /* |
2 | * Input matching routines for CLI backend. | |
3 | * | |
4 | * -- | |
5 | * Copyright (C) 2016 Cumulus Networks, Inc. | |
6 | * | |
7 | * This file is part of GNU Zebra. | |
8 | * | |
9 | * GNU Zebra is free software; you can redistribute it and/or modify it | |
10 | * under the terms of the GNU General Public License as published by the | |
11 | * Free Software Foundation; either version 2, or (at your option) any | |
12 | * later version. | |
13 | * | |
14 | * GNU Zebra is distributed in the hope that it will be useful, but | |
15 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
17 | * General Public License for more details. | |
18 | * | |
896014f4 DL |
19 | * You should have received a copy of the GNU General Public License along |
20 | * with this program; see the file COPYING; if not, write to the Free Software | |
21 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
1ab84bf3 QY |
22 | */ |
23 | ||
24 | #include <zebra.h> | |
460a7689 | 25 | |
eceb1066 | 26 | #include "command_match.h" |
9d0662e0 | 27 | #include "memory.h" |
9d0662e0 | 28 | |
7d5718c1 DL |
29 | DEFINE_MTYPE_STATIC(LIB, CMD_MATCHSTACK, "Command Match Stack") |
30 | ||
bb74e5ac | 31 | #define MAXDEPTH 256 |
ee9216cf | 32 | |
54c5dce6 QY |
33 | #ifdef TRACE_MATCHER |
34 | #define TM 1 | |
35 | #else | |
36 | #define TM 0 | |
37 | #endif | |
38 | ||
d62a17ae | 39 | #define trace_matcher(...) \ |
40 | do { \ | |
41 | if (TM) \ | |
42 | fprintf(stderr, __VA_ARGS__); \ | |
43 | } while (0); | |
54c5dce6 | 44 | |
eceb1066 | 45 | /* matcher helper prototypes */ |
d62a17ae | 46 | static int add_nexthops(struct list *, struct graph_node *, |
47 | struct graph_node **, size_t); | |
18be0e59 | 48 | |
8295b504 QY |
49 | static enum matcher_rv command_match_r(struct graph_node *, vector, |
50 | unsigned int, struct graph_node **, | |
51 | struct list **); | |
76699ae7 | 52 | |
d62a17ae | 53 | static int score_precedence(enum cmd_token_type); |
eceb1066 | 54 | |
d62a17ae | 55 | static enum match_type min_match_level(enum cmd_token_type); |
279712aa | 56 | |
d62a17ae | 57 | static void del_arglist(struct list *); |
6d53a10e | 58 | |
d62a17ae | 59 | static struct cmd_token *disambiguate_tokens(struct cmd_token *, |
60 | struct cmd_token *, char *); | |
54431328 | 61 | |
d62a17ae | 62 | static struct list *disambiguate(struct list *, struct list *, vector, |
63 | unsigned int); | |
39fb395f | 64 | |
d62a17ae | 65 | int compare_completions(const void *, const void *); |
ca90e051 | 66 | |
eceb1066 | 67 | /* token matcher prototypes */ |
d62a17ae | 68 | static enum match_type match_token(struct cmd_token *, char *); |
279712aa | 69 | |
d62a17ae | 70 | static enum match_type match_ipv4(const char *); |
eceb1066 | 71 | |
d62a17ae | 72 | static enum match_type match_ipv4_prefix(const char *); |
18be0e59 | 73 | |
d62a17ae | 74 | static enum match_type match_ipv6_prefix(const char *, bool); |
18be0e59 | 75 | |
d62a17ae | 76 | static enum match_type match_range(struct cmd_token *, const char *); |
18be0e59 | 77 | |
d62a17ae | 78 | static enum match_type match_word(struct cmd_token *, const char *); |
18be0e59 | 79 | |
d62a17ae | 80 | static enum match_type match_variable(struct cmd_token *, const char *); |
18be0e59 | 81 | |
9779e3f1 QY |
82 | static enum match_type match_mac(const char *, bool); |
83 | ||
d62a17ae | 84 | enum matcher_rv command_match(struct graph *cmdgraph, vector vline, |
85 | struct list **argv, const struct cmd_element **el) | |
a53fbbf5 | 86 | { |
d62a17ae | 87 | struct graph_node *stack[MAXDEPTH]; |
8295b504 QY |
88 | enum matcher_rv status; |
89 | *argv = NULL; | |
d62a17ae | 90 | |
91 | // prepend a dummy token to match that pesky start node | |
92 | vector vvline = vector_init(vline->alloced + 1); | |
93 | vector_set_index(vvline, 0, (void *)XSTRDUP(MTYPE_TMP, "dummy")); | |
94 | memcpy(vvline->index + 1, vline->index, | |
95 | sizeof(void *) * vline->alloced); | |
96 | vvline->active = vline->active + 1; | |
97 | ||
98 | struct graph_node *start = vector_slot(cmdgraph->nodes, 0); | |
8295b504 QY |
99 | status = command_match_r(start, vvline, 0, stack, argv); |
100 | if (status == MATCHER_OK) { // successful match | |
d62a17ae | 101 | struct listnode *head = listhead(*argv); |
102 | struct listnode *tail = listtail(*argv); | |
103 | ||
104 | // delete dummy start node | |
105 | cmd_token_del((struct cmd_token *)head->data); | |
106 | list_delete_node(*argv, head); | |
107 | ||
108 | // get cmd_element out of list tail | |
109 | *el = listgetdata(tail); | |
110 | list_delete_node(*argv, tail); | |
111 | ||
112 | // now argv is an ordered list of cmd_token matching the user | |
113 | // input, with each cmd_token->arg holding the corresponding | |
114 | // input | |
115 | assert(*el); | |
8295b504 QY |
116 | } else if (*argv) { |
117 | del_arglist(*argv); | |
118 | *argv = NULL; | |
d62a17ae | 119 | } |
120 | ||
121 | if (!*el) { | |
122 | trace_matcher("No match\n"); | |
123 | } else { | |
124 | trace_matcher("Matched command\n->string %s\n->desc %s\n", | |
125 | (*el)->string, (*el)->doc); | |
126 | } | |
127 | ||
128 | // free the leader token we alloc'd | |
129 | XFREE(MTYPE_TMP, vector_slot(vvline, 0)); | |
130 | // free vector | |
131 | vector_free(vvline); | |
132 | ||
8295b504 | 133 | return status; |
a53fbbf5 | 134 | } |
a53fbbf5 | 135 | |
76699ae7 | 136 | /** |
6ce82b63 | 137 | * Builds an argument list given a DFA and a matching input line. |
76699ae7 | 138 | * |
de9d7e4f | 139 | * First the function determines if the node it is passed matches the first |
39fb395f QY |
140 | * token of input. If it does not, it returns NULL (MATCHER_NO_MATCH). If it |
141 | * does match, then it saves the input token as the head of an argument list. | |
76699ae7 | 142 | * |
de9d7e4f QY |
143 | * The next step is to see if there is further input in the input line. If |
144 | * there is not, the current node's children are searched to see if any of them | |
1eb5e8dc | 145 | * are leaves (type END_TKN). If this is the case, then the bottom of the |
39fb395f QY |
146 | * recursion stack has been reached, the leaf is pushed onto the argument list, |
147 | * the current node is pushed, and the resulting argument list is | |
148 | * returned (MATCHER_OK). If it is not the case, NULL is returned, indicating | |
149 | * that there is no match for the input along this path (MATCHER_INCOMPLETE). | |
76699ae7 | 150 | * |
de9d7e4f QY |
151 | * If there is further input, then the function recurses on each of the current |
152 | * node's children, passing them the input line minus the token that was just | |
153 | * matched. For each child, the return value of the recursive call is | |
154 | * inspected. If it is null, then there is no match for the input along the | |
155 | * subgraph headed by that child. If it is not null, then there is at least one | |
156 | * input match in that subgraph (more on this in a moment). | |
76699ae7 QY |
157 | * |
158 | * If a recursive call on a child returns a non-null value, then it has matched | |
159 | * the input given it on the subgraph that starts with that child. However, due | |
160 | * to the flexibility of the grammar, it is sometimes the case that two or more | |
161 | * child graphs match the same input (two or more of the recursive calls have | |
de9d7e4f QY |
162 | * non-NULL return values). This is not a valid state, since only one true |
163 | * match is possible. In order to resolve this conflict, the function keeps a | |
164 | * reference to the child node that most specifically matches the input. This | |
165 | * is done by assigning each node type a precedence. If a child is found to | |
166 | * match the remaining input, then the precedence values of the current | |
167 | * best-matching child and this new match are compared. The node with higher | |
168 | * precedence is kept, and the other match is discarded. Due to the recursive | |
169 | * nature of this function, it is only necessary to compare the precedence of | |
170 | * immediate children, since all subsequent children will already have been | |
171 | * disambiguated in this way. | |
76699ae7 QY |
172 | * |
173 | * In the event that two children are found to match with the same precedence, | |
de9d7e4f | 174 | * then the input is ambiguous for the passed cmd_element and NULL is returned. |
76699ae7 | 175 | * |
1ab84bf3 | 176 | * @param[in] start the start node. |
76699ae7 | 177 | * @param[in] vline the vectorized input line. |
1ab84bf3 | 178 | * @param[in] n the index of the first input token. |
17aca20b QY |
179 | * @return A linked list of n elements. The first n-1 elements are pointers to |
180 | * struct cmd_token and represent the sequence of tokens matched by the input. | |
181 | * The ->arg field of each token points to a copy of the input matched on it. | |
182 | * The final nth element is a pointer to struct cmd_element, which is the | |
183 | * command that was matched. | |
184 | * | |
185 | * If no match was found, the return value is NULL. | |
76699ae7 | 186 | */ |
8295b504 QY |
187 | static enum matcher_rv command_match_r(struct graph_node *start, vector vline, |
188 | unsigned int n, | |
189 | struct graph_node **stack, | |
190 | struct list **currbest) | |
eceb1066 | 191 | { |
d62a17ae | 192 | assert(n < vector_active(vline)); |
4427e9b3 | 193 | |
8295b504 QY |
194 | enum matcher_rv status = MATCHER_NO_MATCH; |
195 | ||
d62a17ae | 196 | // get the minimum match level that can count as a full match |
197 | struct cmd_token *token = start->data; | |
198 | enum match_type minmatch = min_match_level(token->type); | |
4d94b292 | 199 | |
d62a17ae | 200 | /* check history/stack of tokens |
201 | * this disallows matching the same one more than once if there is a | |
202 | * circle in the graph (used for keyword arguments) */ | |
203 | if (n == MAXDEPTH) | |
8295b504 | 204 | return MATCHER_NO_MATCH; |
d62a17ae | 205 | if (!token->allowrepeat) |
206 | for (size_t s = 0; s < n; s++) | |
207 | if (stack[s] == start) | |
8295b504 | 208 | return MATCHER_NO_MATCH; |
7d5718c1 | 209 | |
d62a17ae | 210 | // get the current operating input token |
211 | char *input_token = vector_slot(vline, n); | |
e1cbb2ff | 212 | |
9dec6b44 | 213 | #ifdef TRACE_MATCHER |
d62a17ae | 214 | fprintf(stdout, "\"%-20s\" matches \"%-30s\" ? ", input_token, |
215 | token->text); | |
216 | enum match_type mt = match_token(token, input_token); | |
d114b977 | 217 | fprintf(stdout, "type: %d ", token->type); |
d62a17ae | 218 | fprintf(stdout, "min: %d - ", minmatch); |
219 | switch (mt) { | |
220 | case trivial_match: | |
221 | fprintf(stdout, "trivial_match "); | |
222 | break; | |
223 | case no_match: | |
224 | fprintf(stdout, "no_match "); | |
225 | break; | |
226 | case partly_match: | |
227 | fprintf(stdout, "partly_match "); | |
228 | break; | |
229 | case exact_match: | |
230 | fprintf(stdout, "exact_match "); | |
231 | break; | |
232 | } | |
233 | if (mt >= minmatch) | |
234 | fprintf(stdout, " MATCH"); | |
235 | fprintf(stdout, "\n"); | |
9dec6b44 | 236 | #endif |
b4f56274 | 237 | |
d62a17ae | 238 | // if we don't match this node, die |
239 | if (match_token(token, input_token) < minmatch) | |
8295b504 | 240 | return MATCHER_NO_MATCH; |
d62a17ae | 241 | |
242 | stack[n] = start; | |
243 | ||
244 | // pointers for iterating linklist | |
245 | struct listnode *ln; | |
246 | struct graph_node *gn; | |
247 | ||
248 | // get all possible nexthops | |
249 | struct list *next = list_new(); | |
250 | add_nexthops(next, start, NULL, 0); | |
251 | ||
252 | // determine the best match | |
d62a17ae | 253 | for (ALL_LIST_ELEMENTS_RO(next, ln, gn)) { |
254 | // if we've matched all input we're looking for END_TKN | |
255 | if (n + 1 == vector_active(vline)) { | |
256 | struct cmd_token *tok = gn->data; | |
257 | if (tok->type == END_TKN) { | |
8295b504 QY |
258 | // if more than one END_TKN in the follow set |
259 | if (*currbest) { | |
260 | status = MATCHER_AMBIGUOUS; | |
d62a17ae | 261 | break; |
8295b504 QY |
262 | } else { |
263 | status = MATCHER_OK; | |
d62a17ae | 264 | } |
8295b504 | 265 | *currbest = list_new(); |
d62a17ae | 266 | // node should have one child node with the |
267 | // element | |
268 | struct graph_node *leaf = | |
269 | vector_slot(gn->to, 0); | |
270 | // last node in the list will hold the | |
8295b504 QY |
271 | // cmd_element; this is important because |
272 | // list_delete() expects that all nodes have | |
273 | // the same data type, so when deleting this | |
274 | // list the last node must be manually deleted | |
d62a17ae | 275 | struct cmd_element *el = leaf->data; |
8295b504 QY |
276 | listnode_add(*currbest, el); |
277 | (*currbest)->del = | |
d62a17ae | 278 | (void (*)(void *)) & cmd_token_del; |
279 | // do not break immediately; continue walking | |
8295b504 QY |
280 | // through the follow set to ensure that there |
281 | // is exactly one END_TKN | |
d62a17ae | 282 | } |
283 | continue; | |
284 | } | |
285 | ||
286 | // else recurse on candidate child node | |
8295b504 QY |
287 | struct list *result = NULL; |
288 | enum matcher_rv rstat = | |
289 | command_match_r(gn, vline, n + 1, stack, &result); | |
d62a17ae | 290 | |
291 | // save the best match | |
8295b504 | 292 | if (result && *currbest) { |
d62a17ae | 293 | // pick the best of two matches |
294 | struct list *newbest = | |
8295b504 QY |
295 | disambiguate(*currbest, result, vline, n + 1); |
296 | ||
297 | // current best and result are ambiguous | |
298 | if (!newbest) | |
299 | status = MATCHER_AMBIGUOUS; | |
300 | // current best is still the best, but ambiguous | |
301 | else if (newbest == *currbest | |
302 | && status == MATCHER_AMBIGUOUS) | |
303 | status = MATCHER_AMBIGUOUS; | |
304 | // result is better, but also ambiguous | |
305 | else if (newbest == result | |
306 | && rstat == MATCHER_AMBIGUOUS) | |
307 | status = MATCHER_AMBIGUOUS; | |
308 | // one or the other is superior and not ambiguous | |
309 | else | |
310 | status = MATCHER_OK; | |
311 | ||
d62a17ae | 312 | // delete the unnecessary result |
313 | struct list *todelete = | |
8295b504 | 314 | ((newbest && newbest == result) ? *currbest |
d62a17ae | 315 | : result); |
316 | del_arglist(todelete); | |
317 | ||
8295b504 QY |
318 | *currbest = newbest ? newbest : *currbest; |
319 | } else if (result) { | |
320 | status = rstat; | |
321 | *currbest = result; | |
322 | } else if (!*currbest) { | |
323 | status = MAX(rstat, status); | |
d62a17ae | 324 | } |
8295b504 QY |
325 | } |
326 | if (*currbest) { | |
327 | // copy token, set arg and prepend to currbest | |
328 | struct cmd_token *token = start->data; | |
329 | struct cmd_token *copy = cmd_token_dup(token); | |
330 | copy->arg = XSTRDUP(MTYPE_CMD_ARG, input_token); | |
331 | listnode_add_before(*currbest, (*currbest)->head, copy); | |
332 | } else if (n + 1 == vector_active(vline) && status == MATCHER_NO_MATCH) | |
333 | status = MATCHER_INCOMPLETE; | |
d62a17ae | 334 | |
335 | // cleanup | |
affe9e99 | 336 | list_delete_and_null(&next); |
d62a17ae | 337 | |
8295b504 | 338 | return status; |
de9d7e4f QY |
339 | } |
340 | ||
d62a17ae | 341 | static void stack_del(void *val) |
7d5718c1 | 342 | { |
d62a17ae | 343 | XFREE(MTYPE_CMD_MATCHSTACK, val); |
7d5718c1 DL |
344 | } |
345 | ||
d62a17ae | 346 | enum matcher_rv command_complete(struct graph *graph, vector vline, |
347 | struct list **completions) | |
de9d7e4f | 348 | { |
d62a17ae | 349 | // pointer to next input token to match |
350 | char *input_token; | |
351 | ||
352 | struct list * | |
353 | current = | |
354 | list_new(), // current nodes to match input token against | |
355 | *next = list_new(); // possible next hops after current input | |
356 | // token | |
357 | current->del = next->del = stack_del; | |
358 | ||
359 | // pointers used for iterating lists | |
360 | struct graph_node **gstack, **newstack; | |
361 | struct listnode *node; | |
362 | ||
363 | // add all children of start node to list | |
364 | struct graph_node *start = vector_slot(graph->nodes, 0); | |
365 | add_nexthops(next, start, &start, 0); | |
366 | ||
367 | unsigned int idx; | |
368 | for (idx = 0; idx < vector_active(vline) && next->count > 0; idx++) { | |
affe9e99 | 369 | list_delete_and_null(¤t); |
d62a17ae | 370 | current = next; |
371 | next = list_new(); | |
372 | next->del = stack_del; | |
373 | ||
374 | input_token = vector_slot(vline, idx); | |
375 | ||
376 | int exact_match_exists = 0; | |
377 | for (ALL_LIST_ELEMENTS_RO(current, node, gstack)) | |
378 | if (!exact_match_exists) | |
379 | exact_match_exists = | |
380 | (match_token(gstack[0]->data, | |
381 | input_token) | |
382 | == exact_match); | |
383 | else | |
384 | break; | |
385 | ||
386 | for (ALL_LIST_ELEMENTS_RO(current, node, gstack)) { | |
387 | struct cmd_token *token = gstack[0]->data; | |
388 | ||
389 | if (token->attr == CMD_ATTR_HIDDEN | |
390 | || token->attr == CMD_ATTR_DEPRECATED) | |
391 | continue; | |
392 | ||
393 | enum match_type minmatch = min_match_level(token->type); | |
394 | trace_matcher("\"%s\" matches \"%s\" (%d) ? ", | |
395 | input_token, token->text, token->type); | |
396 | ||
397 | unsigned int last_token = | |
398 | (vector_active(vline) - 1 == idx); | |
399 | enum match_type matchtype = | |
400 | match_token(token, input_token); | |
401 | switch (matchtype) { | |
402 | // occurs when last token is whitespace | |
403 | case trivial_match: | |
404 | trace_matcher("trivial_match\n"); | |
405 | assert(last_token); | |
406 | newstack = XMALLOC(MTYPE_CMD_MATCHSTACK, | |
407 | sizeof(struct graph_node *)); | |
408 | /* we're not recursing here, just the first | |
409 | * element is OK */ | |
410 | newstack[0] = gstack[0]; | |
411 | listnode_add(next, newstack); | |
412 | break; | |
413 | case partly_match: | |
414 | trace_matcher("trivial_match\n"); | |
415 | if (exact_match_exists && !last_token) | |
416 | break; | |
417 | /* fallthru */ | |
418 | case exact_match: | |
419 | trace_matcher("exact_match\n"); | |
420 | if (last_token) { | |
421 | newstack = XMALLOC( | |
422 | MTYPE_CMD_MATCHSTACK, | |
423 | sizeof(struct graph_node *)); | |
424 | /* same as above, not recursing on this | |
425 | */ | |
426 | newstack[0] = gstack[0]; | |
427 | listnode_add(next, newstack); | |
428 | } else if (matchtype >= minmatch) | |
429 | add_nexthops(next, gstack[0], gstack, | |
430 | idx + 1); | |
431 | break; | |
432 | default: | |
433 | trace_matcher("no_match\n"); | |
434 | break; | |
435 | } | |
436 | } | |
437 | } | |
438 | ||
439 | /* Variable summary | |
440 | * ----------------------------------------------------------------- | |
441 | * token = last input token processed | |
442 | * idx = index in `command` of last token processed | |
443 | * current = set of all transitions from the previous input token | |
444 | * next = set of all nodes reachable from all nodes in `matched` | |
445 | */ | |
446 | ||
935cee3f QY |
447 | enum matcher_rv mrv = idx == vector_active(vline) && next->count |
448 | ? MATCHER_OK | |
449 | : MATCHER_NO_MATCH; | |
d62a17ae | 450 | |
451 | *completions = NULL; | |
935cee3f | 452 | if (!MATCHER_ERROR(mrv)) { |
d62a17ae | 453 | // extract cmd_token into list |
454 | *completions = list_new(); | |
455 | for (ALL_LIST_ELEMENTS_RO(next, node, gstack)) { | |
456 | listnode_add(*completions, gstack[0]->data); | |
457 | } | |
458 | } | |
459 | ||
affe9e99 DS |
460 | list_delete_and_null(¤t); |
461 | list_delete_and_null(&next); | |
d62a17ae | 462 | |
935cee3f | 463 | return mrv; |
eceb1066 | 464 | } |
18be0e59 | 465 | |
de9d7e4f | 466 | /** |
1ab84bf3 | 467 | * Adds all children that are reachable by one parser hop to the given list. |
0bf5b1cb | 468 | * special tokens except END_TKN are treated as transparent. |
de9d7e4f | 469 | * |
1ab84bf3 QY |
470 | * @param[in] list to add the nexthops to |
471 | * @param[in] node to start calculating nexthops from | |
7d5718c1 DL |
472 | * @param[in] stack listing previously visited nodes, if non-NULL. |
473 | * @param[in] stackpos how many valid entries are in stack | |
de9d7e4f | 474 | * @return the number of children added to the list |
7d5718c1 DL |
475 | * |
476 | * NB: non-null "stack" means that new stacks will be added to "list" as | |
477 | * output, instead of direct node pointers! | |
de9d7e4f | 478 | */ |
d62a17ae | 479 | static int add_nexthops(struct list *list, struct graph_node *node, |
480 | struct graph_node **stack, size_t stackpos) | |
de9d7e4f | 481 | { |
d62a17ae | 482 | int added = 0; |
483 | struct graph_node *child; | |
484 | struct graph_node **nextstack; | |
485 | for (unsigned int i = 0; i < vector_active(node->to); i++) { | |
486 | child = vector_slot(node->to, i); | |
487 | size_t j; | |
488 | struct cmd_token *token = child->data; | |
489 | if (!token->allowrepeat && stack) { | |
490 | for (j = 0; j < stackpos; j++) | |
491 | if (child == stack[j]) | |
492 | break; | |
493 | if (j != stackpos) | |
494 | continue; | |
495 | } | |
496 | if (token->type >= SPECIAL_TKN && token->type != END_TKN) { | |
497 | added += add_nexthops(list, child, stack, stackpos); | |
498 | } else { | |
499 | if (stack) { | |
500 | nextstack = XMALLOC( | |
501 | MTYPE_CMD_MATCHSTACK, | |
502 | (stackpos + 1) | |
503 | * sizeof(struct graph_node *)); | |
504 | nextstack[0] = child; | |
505 | memcpy(nextstack + 1, stack, | |
506 | stackpos * sizeof(struct graph_node *)); | |
507 | ||
508 | listnode_add(list, nextstack); | |
509 | } else | |
510 | listnode_add(list, child); | |
511 | added++; | |
512 | } | |
513 | } | |
514 | ||
515 | return added; | |
de9d7e4f QY |
516 | } |
517 | ||
6d53a10e | 518 | /** |
54431328 QY |
519 | * Determines the node types for which a partial match may count as a full |
520 | * match. Enables command abbrevations. | |
1ab84bf3 QY |
521 | * |
522 | * @param[in] type node type | |
523 | * @return minimum match level needed to for a token to fully match | |
6d53a10e | 524 | */ |
d62a17ae | 525 | static enum match_type min_match_level(enum cmd_token_type type) |
6d53a10e | 526 | { |
d62a17ae | 527 | switch (type) { |
528 | // anything matches a start node, for the sake of recursion | |
529 | case START_TKN: | |
530 | return no_match; | |
531 | // allowing words to partly match enables command abbreviation | |
532 | case WORD_TKN: | |
533 | return partly_match; | |
534 | default: | |
535 | return exact_match; | |
536 | } | |
6d53a10e QY |
537 | } |
538 | ||
1ab84bf3 QY |
539 | /** |
540 | * Assigns precedence scores to node types. | |
541 | * | |
542 | * @param[in] type node type to score | |
543 | * @return precedence score | |
544 | */ | |
d62a17ae | 545 | static int score_precedence(enum cmd_token_type type) |
76699ae7 | 546 | { |
d62a17ae | 547 | switch (type) { |
548 | // some of these are mutually exclusive, so they share | |
549 | // the same precedence value | |
550 | case IPV4_TKN: | |
551 | case IPV4_PREFIX_TKN: | |
552 | case IPV6_TKN: | |
553 | case IPV6_PREFIX_TKN: | |
9779e3f1 QY |
554 | case MAC_TKN: |
555 | case MAC_PREFIX_TKN: | |
d62a17ae | 556 | case RANGE_TKN: |
557 | return 2; | |
558 | case WORD_TKN: | |
559 | return 3; | |
560 | case VARIABLE_TKN: | |
561 | return 4; | |
562 | default: | |
563 | return 10; | |
564 | } | |
76699ae7 QY |
565 | } |
566 | ||
1ab84bf3 QY |
567 | /** |
568 | * Picks the better of two possible matches for a token. | |
569 | * | |
570 | * @param[in] first candidate node matching token | |
571 | * @param[in] second candidate node matching token | |
572 | * @param[in] token the token being matched | |
573 | * @return the best-matching node, or NULL if the two are entirely ambiguous | |
574 | */ | |
d62a17ae | 575 | static struct cmd_token *disambiguate_tokens(struct cmd_token *first, |
576 | struct cmd_token *second, | |
577 | char *input_token) | |
54431328 | 578 | { |
d62a17ae | 579 | // if the types are different, simply go off of type precedence |
580 | if (first->type != second->type) { | |
581 | int firstprec = score_precedence(first->type); | |
582 | int secndprec = score_precedence(second->type); | |
583 | if (firstprec != secndprec) | |
584 | return firstprec < secndprec ? first : second; | |
585 | else | |
586 | return NULL; | |
587 | } | |
588 | ||
589 | // if they're the same, return the more exact match | |
590 | enum match_type fmtype = match_token(first, input_token); | |
591 | enum match_type smtype = match_token(second, input_token); | |
592 | if (fmtype != smtype) | |
593 | return fmtype > smtype ? first : second; | |
594 | ||
595 | return NULL; | |
54431328 QY |
596 | } |
597 | ||
1ab84bf3 QY |
598 | /** |
599 | * Picks the better of two possible matches for an input line. | |
600 | * | |
d0bfb22c QY |
601 | * @param[in] first candidate list of cmd_token matching vline |
602 | * @param[in] second candidate list of cmd_token matching vline | |
1ab84bf3 QY |
603 | * @param[in] vline the input line being matched |
604 | * @param[in] n index into vline to start comparing at | |
605 | * @return the best-matching list, or NULL if the two are entirely ambiguous | |
606 | */ | |
d62a17ae | 607 | static struct list *disambiguate(struct list *first, struct list *second, |
608 | vector vline, unsigned int n) | |
39fb395f | 609 | { |
d62a17ae | 610 | // doesn't make sense for these to be inequal length |
611 | assert(first->count == second->count); | |
612 | assert(first->count == vector_active(vline) - n + 1); | |
613 | ||
614 | struct listnode *fnode = listhead(first), *snode = listhead(second); | |
615 | struct cmd_token *ftok = listgetdata(fnode), *stok = listgetdata(snode), | |
616 | *best = NULL; | |
617 | ||
618 | // compare each token, if one matches better use that one | |
619 | for (unsigned int i = n; i < vector_active(vline); i++) { | |
620 | char *token = vector_slot(vline, i); | |
621 | if ((best = disambiguate_tokens(ftok, stok, token))) | |
622 | return best == ftok ? first : second; | |
623 | fnode = listnextnode(fnode); | |
624 | snode = listnextnode(snode); | |
625 | ftok = listgetdata(fnode); | |
626 | stok = listgetdata(snode); | |
627 | } | |
628 | ||
629 | return NULL; | |
39fb395f QY |
630 | } |
631 | ||
1eb5e8dc QY |
632 | /* |
633 | * Deletion function for arglist. | |
1ab84bf3 | 634 | * |
1eb5e8dc QY |
635 | * Since list->del for arglists expects all listnode->data to hold cmd_token, |
636 | * but arglists have cmd_element as the data for the tail, this function | |
637 | * manually deletes the tail before deleting the rest of the list as usual. | |
638 | * | |
17aca20b QY |
639 | * The cmd_element at the end is *not* a copy. It is the one and only. |
640 | * | |
1eb5e8dc | 641 | * @param list the arglist to delete |
1ab84bf3 | 642 | */ |
d62a17ae | 643 | static void del_arglist(struct list *list) |
54431328 | 644 | { |
d62a17ae | 645 | // manually delete last node |
646 | struct listnode *tail = listtail(list); | |
647 | tail->data = NULL; | |
648 | list_delete_node(list, tail); | |
1eb5e8dc | 649 | |
d62a17ae | 650 | // delete the rest of the list as usual |
affe9e99 | 651 | list_delete_and_null(&list); |
54431328 QY |
652 | } |
653 | ||
1eb5e8dc | 654 | /*---------- token level matching functions ----------*/ |
54431328 | 655 | |
d62a17ae | 656 | static enum match_type match_token(struct cmd_token *token, char *input_token) |
880e24a1 | 657 | { |
d62a17ae | 658 | // nothing trivially matches everything |
659 | if (!input_token) | |
660 | return trivial_match; | |
661 | ||
662 | switch (token->type) { | |
663 | case WORD_TKN: | |
664 | return match_word(token, input_token); | |
665 | case IPV4_TKN: | |
666 | return match_ipv4(input_token); | |
667 | case IPV4_PREFIX_TKN: | |
668 | return match_ipv4_prefix(input_token); | |
669 | case IPV6_TKN: | |
670 | return match_ipv6_prefix(input_token, false); | |
671 | case IPV6_PREFIX_TKN: | |
672 | return match_ipv6_prefix(input_token, true); | |
673 | case RANGE_TKN: | |
674 | return match_range(token, input_token); | |
675 | case VARIABLE_TKN: | |
676 | return match_variable(token, input_token); | |
9779e3f1 QY |
677 | case MAC_TKN: |
678 | return match_mac(input_token, false); | |
679 | case MAC_PREFIX_TKN: | |
680 | return match_mac(input_token, true); | |
d62a17ae | 681 | case END_TKN: |
682 | default: | |
683 | return no_match; | |
684 | } | |
9d0662e0 QY |
685 | } |
686 | ||
9d0662e0 QY |
687 | #define IPV4_ADDR_STR "0123456789." |
688 | #define IPV4_PREFIX_STR "0123456789./" | |
689 | ||
d62a17ae | 690 | static enum match_type match_ipv4(const char *str) |
9d0662e0 | 691 | { |
d62a17ae | 692 | const char *sp; |
693 | int dots = 0, nums = 0; | |
694 | char buf[4]; | |
695 | ||
696 | for (;;) { | |
697 | memset(buf, 0, sizeof(buf)); | |
698 | sp = str; | |
699 | while (*str != '\0') { | |
700 | if (*str == '.') { | |
701 | if (dots >= 3) | |
702 | return no_match; | |
703 | ||
704 | if (*(str + 1) == '.') | |
705 | return no_match; | |
706 | ||
707 | if (*(str + 1) == '\0') | |
708 | return partly_match; | |
709 | ||
710 | dots++; | |
711 | break; | |
712 | } | |
713 | if (!isdigit((int)*str)) | |
714 | return no_match; | |
715 | ||
716 | str++; | |
717 | } | |
718 | ||
719 | if (str - sp > 3) | |
720 | return no_match; | |
9d0662e0 | 721 | |
d62a17ae | 722 | strncpy(buf, sp, str - sp); |
723 | if (atoi(buf) > 255) | |
724 | return no_match; | |
9d0662e0 | 725 | |
d62a17ae | 726 | nums++; |
0b02e39d | 727 | |
d62a17ae | 728 | if (*str == '\0') |
729 | break; | |
730 | ||
731 | str++; | |
732 | } | |
0b02e39d | 733 | |
d62a17ae | 734 | if (nums < 4) |
735 | return partly_match; | |
0b02e39d | 736 | |
d62a17ae | 737 | return exact_match; |
738 | } | |
0b02e39d | 739 | |
d62a17ae | 740 | static enum match_type match_ipv4_prefix(const char *str) |
741 | { | |
742 | const char *sp; | |
743 | int dots = 0; | |
744 | char buf[4]; | |
0b02e39d | 745 | |
d62a17ae | 746 | for (;;) { |
747 | memset(buf, 0, sizeof(buf)); | |
748 | sp = str; | |
749 | while (*str != '\0' && *str != '/') { | |
750 | if (*str == '.') { | |
751 | if (dots == 3) | |
752 | return no_match; | |
0b02e39d | 753 | |
d62a17ae | 754 | if (*(str + 1) == '.' || *(str + 1) == '/') |
755 | return no_match; | |
0b02e39d | 756 | |
d62a17ae | 757 | if (*(str + 1) == '\0') |
758 | return partly_match; | |
0b02e39d | 759 | |
d62a17ae | 760 | dots++; |
761 | break; | |
762 | } | |
0b02e39d | 763 | |
d62a17ae | 764 | if (!isdigit((int)*str)) |
765 | return no_match; | |
9d0662e0 | 766 | |
d62a17ae | 767 | str++; |
768 | } | |
9d0662e0 | 769 | |
d62a17ae | 770 | if (str - sp > 3) |
771 | return no_match; | |
772 | ||
773 | strncpy(buf, sp, str - sp); | |
774 | if (atoi(buf) > 255) | |
775 | return no_match; | |
776 | ||
777 | if (dots == 3) { | |
778 | if (*str == '/') { | |
779 | if (*(str + 1) == '\0') | |
780 | return partly_match; | |
781 | ||
782 | str++; | |
783 | break; | |
784 | } else if (*str == '\0') | |
785 | return partly_match; | |
786 | } | |
787 | ||
788 | if (*str == '\0') | |
789 | return partly_match; | |
790 | ||
791 | str++; | |
792 | } | |
793 | ||
794 | sp = str; | |
795 | while (*str != '\0') { | |
796 | if (!isdigit((int)*str)) | |
797 | return no_match; | |
798 | ||
799 | str++; | |
800 | } | |
801 | ||
802 | if (atoi(sp) > 32) | |
803 | return no_match; | |
804 | ||
805 | return exact_match; | |
9d0662e0 QY |
806 | } |
807 | ||
ee9216cf | 808 | |
9d0662e0 QY |
809 | #define IPV6_ADDR_STR "0123456789abcdefABCDEF:." |
810 | #define IPV6_PREFIX_STR "0123456789abcdefABCDEF:./" | |
ee9216cf QY |
811 | #define STATE_START 1 |
812 | #define STATE_COLON 2 | |
813 | #define STATE_DOUBLE 3 | |
814 | #define STATE_ADDR 4 | |
815 | #define STATE_DOT 5 | |
816 | #define STATE_SLASH 6 | |
817 | #define STATE_MASK 7 | |
9d0662e0 | 818 | |
d62a17ae | 819 | static enum match_type match_ipv6_prefix(const char *str, bool prefix) |
9d0662e0 | 820 | { |
d62a17ae | 821 | int state = STATE_START; |
822 | int colons = 0, nums = 0, double_colon = 0; | |
823 | int mask; | |
824 | const char *sp = NULL, *start = str; | |
825 | char *endptr = NULL; | |
2d21bc75 | 826 | |
d62a17ae | 827 | if (str == NULL) |
828 | return partly_match; | |
9d0662e0 | 829 | |
d62a17ae | 830 | if (strspn(str, prefix ? IPV6_PREFIX_STR : IPV6_ADDR_STR) |
831 | != strlen(str)) | |
2d21bc75 | 832 | return no_match; |
2d21bc75 | 833 | |
d62a17ae | 834 | while (*str != '\0' && state != STATE_MASK) { |
835 | switch (state) { | |
836 | case STATE_START: | |
837 | if (*str == ':') { | |
838 | if (*(str + 1) != ':' && *(str + 1) != '\0') | |
839 | return no_match; | |
840 | colons--; | |
841 | state = STATE_COLON; | |
842 | } else { | |
843 | sp = str; | |
844 | state = STATE_ADDR; | |
845 | } | |
846 | ||
847 | continue; | |
848 | case STATE_COLON: | |
849 | colons++; | |
850 | if (*(str + 1) == '/') | |
851 | return no_match; | |
852 | else if (*(str + 1) == ':') | |
853 | state = STATE_DOUBLE; | |
854 | else { | |
855 | sp = str + 1; | |
856 | state = STATE_ADDR; | |
857 | } | |
858 | break; | |
859 | case STATE_DOUBLE: | |
860 | if (double_colon) | |
861 | return no_match; | |
862 | ||
863 | if (*(str + 1) == ':') | |
864 | return no_match; | |
865 | else { | |
866 | if (*(str + 1) != '\0' && *(str + 1) != '/') | |
867 | colons++; | |
868 | sp = str + 1; | |
869 | ||
870 | if (*(str + 1) == '/') | |
871 | state = STATE_SLASH; | |
872 | else | |
873 | state = STATE_ADDR; | |
874 | } | |
875 | ||
876 | double_colon++; | |
877 | nums += 1; | |
878 | break; | |
879 | case STATE_ADDR: | |
880 | if (*(str + 1) == ':' || *(str + 1) == '.' | |
881 | || *(str + 1) == '\0' || *(str + 1) == '/') { | |
882 | if (str - sp > 3) | |
883 | return no_match; | |
884 | ||
885 | for (; sp <= str; sp++) | |
886 | if (*sp == '/') | |
887 | return no_match; | |
888 | ||
889 | nums++; | |
890 | ||
891 | if (*(str + 1) == ':') | |
892 | state = STATE_COLON; | |
893 | else if (*(str + 1) == '.') { | |
894 | if (colons || double_colon) | |
895 | state = STATE_DOT; | |
896 | else | |
897 | return no_match; | |
898 | } else if (*(str + 1) == '/') | |
899 | state = STATE_SLASH; | |
900 | } | |
901 | break; | |
902 | case STATE_DOT: | |
903 | state = STATE_ADDR; | |
904 | break; | |
905 | case STATE_SLASH: | |
906 | if (*(str + 1) == '\0') | |
907 | return partly_match; | |
908 | ||
909 | state = STATE_MASK; | |
910 | break; | |
911 | default: | |
912 | break; | |
2d21bc75 | 913 | } |
2d21bc75 | 914 | |
d62a17ae | 915 | if (nums > 11) |
916 | return no_match; | |
2d21bc75 | 917 | |
d62a17ae | 918 | if (colons > 7) |
919 | return no_match; | |
9d0662e0 | 920 | |
d62a17ae | 921 | str++; |
922 | } | |
9d0662e0 | 923 | |
d62a17ae | 924 | if (!prefix) { |
925 | struct sockaddr_in6 sin6_dummy; | |
926 | int ret = inet_pton(AF_INET6, start, &sin6_dummy.sin6_addr); | |
927 | return ret == 1 ? exact_match : partly_match; | |
928 | } | |
9a7fc1bd | 929 | |
d62a17ae | 930 | if (state < STATE_MASK) |
931 | return partly_match; | |
040f3984 | 932 | |
d62a17ae | 933 | mask = strtol(str, &endptr, 10); |
934 | if (*endptr != '\0') | |
935 | return no_match; | |
2d21bc75 | 936 | |
d62a17ae | 937 | if (mask < 0 || mask > 128) |
938 | return no_match; | |
9d0662e0 | 939 | |
d62a17ae | 940 | return exact_match; |
9d0662e0 | 941 | } |
9d0662e0 | 942 | |
d62a17ae | 943 | static enum match_type match_range(struct cmd_token *token, const char *str) |
9d0662e0 | 944 | { |
d62a17ae | 945 | assert(token->type == RANGE_TKN); |
1ab84bf3 | 946 | |
d62a17ae | 947 | char *endptr = NULL; |
948 | long long val; | |
9d0662e0 | 949 | |
d62a17ae | 950 | val = strtoll(str, &endptr, 10); |
951 | if (*endptr != '\0') | |
952 | return no_match; | |
9d0662e0 | 953 | |
d62a17ae | 954 | if (val < token->min || val > token->max) |
955 | return no_match; | |
956 | else | |
957 | return exact_match; | |
9d0662e0 QY |
958 | } |
959 | ||
d62a17ae | 960 | static enum match_type match_word(struct cmd_token *token, const char *word) |
9d0662e0 | 961 | { |
d62a17ae | 962 | assert(token->type == WORD_TKN); |
1ab84bf3 | 963 | |
d62a17ae | 964 | // if the passed token is 0 length, partly match |
965 | if (!strlen(word)) | |
966 | return partly_match; | |
e1cbb2ff | 967 | |
d62a17ae | 968 | // if the passed token is strictly a prefix of the full word, partly |
969 | // match | |
970 | if (strlen(word) < strlen(token->text)) | |
971 | return !strncmp(token->text, word, strlen(word)) ? partly_match | |
972 | : no_match; | |
e1cbb2ff | 973 | |
d62a17ae | 974 | // if they are the same length and exactly equal, exact match |
975 | else if (strlen(word) == strlen(token->text)) | |
976 | return !strncmp(token->text, word, strlen(word)) ? exact_match | |
977 | : no_match; | |
e1cbb2ff | 978 | |
d62a17ae | 979 | return no_match; |
a53fbbf5 | 980 | } |
9d0662e0 | 981 | |
d62a17ae | 982 | static enum match_type match_variable(struct cmd_token *token, const char *word) |
a53fbbf5 | 983 | { |
d62a17ae | 984 | assert(token->type == VARIABLE_TKN); |
985 | return exact_match; | |
9d0662e0 | 986 | } |
9779e3f1 QY |
987 | |
988 | #define MAC_CHARS "ABCDEFabcdef0123456789:" | |
989 | ||
990 | static enum match_type match_mac(const char *word, bool prefix) | |
991 | { | |
992 | /* 6 2-digit hex numbers separated by 5 colons */ | |
993 | size_t mac_explen = 6 * 2 + 5; | |
994 | /* '/' + 2-digit integer */ | |
995 | size_t mask_len = 1 + 2; | |
996 | unsigned int i; | |
997 | char *eptr; | |
998 | unsigned int maskval; | |
999 | ||
1000 | /* length check */ | |
1001 | if (strlen(word) > mac_explen + (prefix ? mask_len : 0)) | |
1002 | return no_match; | |
1003 | ||
1004 | /* address check */ | |
1005 | for (i = 0; i < mac_explen; i++) { | |
1006 | if (word[i] == '\0' || !strchr(MAC_CHARS, word[i])) | |
1007 | break; | |
1008 | if (((i + 1) % 3 == 0) != (word[i] == ':')) | |
1009 | return no_match; | |
1010 | } | |
1011 | ||
1012 | /* incomplete address */ | |
1013 | if (i < mac_explen && word[i] == '\0') | |
1014 | return partly_match; | |
1015 | else if (i < mac_explen) | |
1016 | return no_match; | |
1017 | ||
1018 | /* mask check */ | |
1019 | if (prefix && word[i] == '/') { | |
1020 | if (word[++i] == '\0') | |
1021 | return partly_match; | |
1022 | ||
1023 | maskval = strtoul(&word[i], &eptr, 10); | |
1024 | if (*eptr != '\0' || maskval > 48) | |
1025 | return no_match; | |
1026 | } else if (prefix && word[i] == '\0') { | |
1027 | return partly_match; | |
1028 | } else if (prefix) { | |
1029 | return no_match; | |
1030 | } | |
1031 | ||
1032 | return exact_match; | |
1033 | } |