d11a0bf7 |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: key-misc.c,v 1.1 1999/12/22 15:47:48 mdw Exp $ |
4 | * |
5 | * Simple key management |
6 | * |
7 | * (c) 1999 Straylight/Edgeware |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of Catacomb. |
13 | * |
14 | * Catacomb is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU Library General Public License as |
16 | * published by the Free Software Foundation; either version 2 of the |
17 | * License, or (at your option) any later version. |
18 | * |
19 | * Catacomb 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 Library General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU Library General Public |
25 | * License along with Catacomb; if not, write to the Free |
26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
27 | * MA 02111-1307, USA. |
28 | */ |
29 | |
30 | /*----- Revision history --------------------------------------------------* |
31 | * |
32 | * $Log: key-misc.c,v $ |
33 | * Revision 1.1 1999/12/22 15:47:48 mdw |
34 | * Major key-management revision. |
35 | * |
36 | */ |
37 | |
38 | /*----- Header files ------------------------------------------------------*/ |
39 | |
40 | #include <stdio.h> |
41 | #include <stdlib.h> |
42 | #include <string.h> |
43 | #include <time.h> |
44 | |
45 | #include <mLib/alloc.h> |
46 | #include <mLib/bits.h> |
47 | #include <mLib/hash.h> |
48 | #include <mLib/sub.h> |
49 | #include <mLib/sym.h> |
50 | |
51 | #include "key.h" |
52 | |
53 | /*----- Useful macros -----------------------------------------------------*/ |
54 | |
55 | #define KEY_WRITE(f) do { \ |
56 | if (!(f)->f & KF_WRITE) \ |
57 | return (KERR_READONLY); \ |
58 | } while (0) |
59 | |
60 | #define KEY_MODIFY(f) do { (f)->f |= KF_MODIFIED; } while (0) |
61 | |
62 | #define KEY_LOAD(n) ((n) * 2) |
63 | |
64 | /*----- Error reporting ---------------------------------------------------*/ |
65 | |
66 | /* --- @key_strerror@ --- * |
67 | * |
68 | * Arguments: @int err@ = error code from @key_new@ |
69 | * |
70 | * Returns: Pointer to error string. |
71 | * |
72 | * Use: Translates a @KERR@ error code into a human-readable |
73 | * string. |
74 | */ |
75 | |
76 | const char *key_strerror(int err) |
77 | { |
78 | char *tab[] = { |
79 | "No error", |
80 | "Bad tag string", |
81 | "Bad type string", |
82 | "Bad comment string", |
83 | "Keyid already exists", |
84 | "Key tag already exists", |
85 | "Key file is read-only", |
86 | "Key will eventually expire", |
87 | "Bad key flags string", |
88 | "Unknown error code" |
89 | }; |
90 | |
91 | unsigned e = -err; |
92 | if (e >= KERR_MAX) |
93 | e = KERR_MAX; |
94 | return (tab[e]); |
95 | } |
96 | |
97 | /*----- Iteration and iterators -------------------------------------------*/ |
98 | |
99 | /* --- @key_mkiter@ --- * |
100 | * |
101 | * Arguments: @key_iter *i@ = pointer to iterator object |
102 | * @key_file *f@ = pointer to file structure |
103 | * |
104 | * Returns: --- |
105 | * |
106 | * Use: Initializes a key iterator. The keys are returned by |
107 | * @key_next@. |
108 | */ |
109 | |
110 | void key_mkiter(key_iter *i, key_file *f) |
111 | { |
112 | HASH_MKITER(&i->i, &f->byid); |
113 | i->t = time(0); |
114 | } |
115 | |
116 | /* --- @key_next@ --- * |
117 | * |
118 | * Arguments: @key_iter *i@ = pointer to iterator object |
119 | * |
120 | * Returns: Pointer to next key, or null. |
121 | * |
122 | * Use: Returns the next key in some arbitrary sequence. |
123 | */ |
124 | |
125 | key *key_next(key_iter *i) |
126 | { |
127 | hash_base *b; |
128 | key *k; |
129 | do { |
130 | HASH_NEXT(&i->i, b); |
131 | k = (key *)b; |
132 | } while (k && KEY_EXPIRED(i->t, k->exp) && KEY_EXPIRED(i->t, k->del)); |
133 | return (k); |
134 | } |
135 | |
136 | /*----- Lookup ------------------------------------------------------------*/ |
137 | |
138 | /* --- @key_bytype@ --- * |
139 | * |
140 | * Arguments: @key_file *f@ = key file we want a key from |
141 | * @const char *type@ = type string for desired key |
142 | * |
143 | * Returns: Pointer to the best key to use, or null. |
144 | * |
145 | * Use: Looks up a key by its type. Returns the key with the latest |
146 | * expiry time. This function will not return an expired key. |
147 | */ |
148 | |
149 | key *key_bytype(key_file *f, const char *type) |
150 | { |
151 | time_t now = time(0); |
152 | key *k; |
153 | key_ref *kr; |
154 | |
155 | if ((kr = sym_find(&f->bytype, type, -1, 0, 0)) == 0) |
156 | return (0); |
157 | for (k = kr->k; k && KEY_EXPIRED(now, k->exp); k = k->next) |
158 | ; |
159 | return (k); |
160 | } |
161 | |
162 | /* --- @key_byid@ --- * |
163 | * |
164 | * Arguments: @key_file *f@ = key file to find a key from |
165 | * @uint32 id@ = id to look for |
166 | * |
167 | * Returns: Key with matching id. |
168 | * |
169 | * Use: Returns a key given its id. This function will return an |
170 | * expired key, but not a deleted one. |
171 | */ |
172 | |
173 | key *key_byid(key_file *f, uint32 id) |
174 | { |
175 | time_t t = time(0); |
176 | hash_base **bin, *b; |
177 | |
178 | bin = HASH_BIN(&f->byid, id); |
179 | for (b = *bin; b; b = b->next) { |
180 | if (b->hash == id) { |
181 | key *k = (key *)b; |
182 | if (KEY_EXPIRED(t, k->exp) && KEY_EXPIRED(t, k->del)) |
183 | return (0); |
184 | return (k); |
185 | } |
186 | } |
187 | return (0); |
188 | } |
189 | |
190 | /* --- @key_bytag@ --- * |
191 | * |
192 | * Arguments: @key_file *f@ = key file to find a key from |
193 | * @const char *tag@ = pointer to tag string |
194 | * |
195 | * Returns: Key with matching id or tag. |
196 | * |
197 | * Use: Returns a key given its tag or id. This function will return |
198 | * an expired key, but not a deleted one. |
199 | */ |
200 | |
201 | key *key_bytag(key_file *f, const char *tag) |
202 | { |
203 | time_t t = time(0); |
204 | char *p; |
205 | uint32 id; |
206 | key_ref *kr = sym_find(&f->bytag, tag, -1, 0, 0); |
207 | |
208 | if (kr && !(KEY_EXPIRED(t, kr->k->exp) && KEY_EXPIRED(t, kr->k->exp))) |
209 | return (kr->k); |
210 | id = strtoul(tag, &p, 16); |
211 | if (!*p) |
212 | return (key_byid(f, id)); |
213 | return (key_bytype(f, tag)); |
214 | } |
215 | |
216 | /* --- @key_qtag@ --- * |
217 | * |
218 | * Arguments: @key_file *f@ = key file to find a key from |
219 | * @const char *tag@ = pointer to tag string |
220 | * @dstr *d@ = pointer to string for full tag name |
221 | * @key **k@ = where to store the key pointer |
222 | * @key_data **kd@ = where to store the key data pointer |
223 | * |
224 | * Returns: Zero if OK, nonzero if it failed. |
225 | * |
226 | * Use: Performs a full lookup on a qualified tag name. The tag is |
227 | * qualified by the names of subkeys, separated by dots. Hence, |
228 | * a qualified tag is ID|TAG[.TAG...]. The various result |
229 | * pointers can be null to indicate that the result isn't |
230 | * interesting. |
231 | */ |
232 | |
233 | int key_qtag(key_file *f, const char *tag, dstr *d, key **k, key_data **kd) |
234 | { |
235 | dstr dd = DSTR_INIT; |
236 | const char *q; |
237 | key *kk; |
238 | key_data *kkd; |
239 | |
240 | /* --- Find the end of the base tag --- */ |
241 | |
242 | if ((q = strchr(tag, '.')) == 0) |
243 | DPUTS(&dd, tag); |
244 | else { |
245 | DPUTM(&dd, tag, q - tag); |
246 | DPUTZ(&dd); |
247 | q++; |
248 | } |
249 | |
250 | /* --- Look up the key tag --- */ |
251 | |
252 | if ((kk = key_bytag(f, dd.buf)) == 0) { |
253 | dstr_destroy(&dd); |
254 | return (-1); |
255 | } |
256 | |
257 | /* --- Set the various initial bits of result up --- */ |
258 | |
259 | if (d) |
260 | key_fulltag(kk, d); |
261 | if (k) |
262 | *k = kk; |
263 | kkd = &kk->k; |
264 | |
265 | /* --- Now dig through the rest of the tag --- */ |
266 | |
267 | while (q && *q) { |
268 | |
269 | /* --- Stick on the next bit of the fullqtag --- */ |
270 | |
271 | DRESET(&dd); |
272 | while (*q && *q != '.') { |
273 | DPUTC(&dd, *q); |
274 | q++; |
275 | } |
276 | DPUTZ(&dd); |
277 | if (d) { |
278 | DPUTC(d, '.'); |
279 | DPUTD(d, &dd); |
280 | } |
281 | |
282 | /* --- Look up the subkey --- */ |
283 | |
284 | if (kkd->e != KENC_STRUCT) { |
285 | kkd = 0; |
286 | break; |
287 | } |
288 | if ((kkd = key_structfind(kkd, dd.buf)) == 0) |
289 | break; |
290 | } |
291 | |
292 | /* --- Return the results --- */ |
293 | |
294 | if (!kkd) |
295 | return (-1); |
296 | dstr_destroy(&dd); |
297 | if (kd) |
298 | *kd = kkd; |
299 | return (0); |
300 | } |
301 | |
302 | /*----- Miscellaneous functions -------------------------------------------*/ |
303 | |
304 | /* --- @key_delete@ --- * |
305 | * |
306 | * Arguments: @key_file *f@ = pointer to file block |
307 | * @key *k@ = key to delete |
308 | * |
309 | * Returns: Error code (one of the @KERR@ constants). |
310 | * |
311 | * Use: Removes the given key from the list. The key file must be |
312 | * writable. (Due to the horridness of the data structures, |
313 | * deleted keys aren't actually removed, just marked so that |
314 | * they can't be looked up or iterated over. One upshot of |
315 | * this is that they don't get written back to the file when |
316 | * it's closed.) |
317 | */ |
318 | |
319 | int key_delete(key_file *f, key *k) |
320 | { |
321 | KEY_WRITE(f); |
322 | k->exp = KEXP_EXPIRE; |
323 | k->del = KEXP_EXPIRE; |
324 | KEY_MODIFY(f); |
325 | return (0); |
326 | } |
327 | |
328 | /* --- @key_expire@ --- * |
329 | * |
330 | * Arguments: @key_file *f@ = pointer to file block |
331 | * @key *k@ = pointer to key block |
332 | * |
333 | * Returns: Error code (one of the @KERR@ constants). |
334 | * |
335 | * Use: Immediately marks the key as expired. It may be removed |
336 | * immediately, if it is no longer required, and will be removed |
337 | * by a tidy operation when it is no longer required. The key |
338 | * file must be writable. |
339 | */ |
340 | |
341 | int key_expire(key_file *f, key *k) |
342 | { |
343 | KEY_WRITE(f); |
344 | k->exp = KEXP_EXPIRE; |
345 | if (k->del == KEXP_FOREVER) |
346 | k->del = KEXP_EXPIRE; |
347 | KEY_MODIFY(f); |
348 | return (0); |
349 | } |
350 | |
351 | /* --- @key_used@ --- * |
352 | * |
353 | * Arguments: @key_file *f@ = pointer to key file |
354 | * @key *k@ = pointer to key block |
355 | * @time_t t@ = when key can be removed |
356 | * |
357 | * Returns: Zero if OK, nonzero on failure. |
358 | * |
359 | * Use: Marks a key as being required until a given time. Even |
360 | * though the key may expire before then (and won't be returned |
361 | * by type after that time), it will still be available when |
362 | * requested explicitly by id. The key file must be writable. |
363 | * |
364 | * The only (current) reason for failure is attempting to use |
365 | * a key which can expire for something which can't. |
366 | */ |
367 | |
368 | int key_used(key_file *f, key *k, time_t t) |
369 | { |
370 | KEY_WRITE(f); |
371 | if (t == KEXP_FOREVER) { |
372 | if (k->exp != KEXP_FOREVER) |
373 | return (KERR_WILLEXPIRE); |
374 | } else if (k->del >= t) |
375 | return (0); |
376 | |
377 | k->del = t; |
378 | KEY_MODIFY(f); |
379 | return (0); |
380 | } |
381 | |
382 | /*----- That's all, folks -------------------------------------------------*/ |