| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * Simple key management |
| 4 | * |
| 5 | * (c) 1999 Straylight/Edgeware |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This file is part of Catacomb. |
| 11 | * |
| 12 | * Catacomb is free software; you can redistribute it and/or modify |
| 13 | * it under the terms of the GNU Library General Public License as |
| 14 | * published by the Free Software Foundation; either version 2 of the |
| 15 | * License, or (at your option) any later version. |
| 16 | * |
| 17 | * Catacomb is distributed in the hope that it will be useful, |
| 18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 20 | * GNU Library General Public License for more details. |
| 21 | * |
| 22 | * You should have received a copy of the GNU Library General Public |
| 23 | * License along with Catacomb; if not, write to the Free |
| 24 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 25 | * MA 02111-1307, USA. |
| 26 | */ |
| 27 | |
| 28 | /*----- Header files ------------------------------------------------------*/ |
| 29 | |
| 30 | #include <stdio.h> |
| 31 | #include <stdlib.h> |
| 32 | #include <string.h> |
| 33 | #include <time.h> |
| 34 | |
| 35 | #include <mLib/bits.h> |
| 36 | #include <mLib/hash.h> |
| 37 | #include <mLib/macros.h> |
| 38 | #include <mLib/sub.h> |
| 39 | #include <mLib/sym.h> |
| 40 | |
| 41 | #include "key.h" |
| 42 | |
| 43 | /*----- Useful macros -----------------------------------------------------*/ |
| 44 | |
| 45 | #define KEY_WRITE(f) do { \ |
| 46 | if (!((f)->f & KF_WRITE)) \ |
| 47 | return (KERR_READONLY); \ |
| 48 | } while (0) |
| 49 | |
| 50 | #define KEY_MODIFY(f) do { (f)->f |= KF_MODIFIED; } while (0) |
| 51 | |
| 52 | #define KEY_LOAD(n) ((n) * 2) |
| 53 | |
| 54 | /*----- Iteration and iterators -------------------------------------------*/ |
| 55 | |
| 56 | /* --- @key_mkiter@ --- * |
| 57 | * |
| 58 | * Arguments: @key_iter *i@ = pointer to iterator object |
| 59 | * @key_file *f@ = pointer to file structure |
| 60 | * |
| 61 | * Returns: --- |
| 62 | * |
| 63 | * Use: Initializes a key iterator. The keys are returned by |
| 64 | * @key_next@. |
| 65 | */ |
| 66 | |
| 67 | void key_mkiter(key_iter *i, key_file *f) |
| 68 | { |
| 69 | HASH_MKITER(&i->i, &f->byid); |
| 70 | i->t = time(0); |
| 71 | } |
| 72 | |
| 73 | /* --- @key_next@ --- * |
| 74 | * |
| 75 | * Arguments: @key_iter *i@ = pointer to iterator object |
| 76 | * |
| 77 | * Returns: Pointer to next key, or null. |
| 78 | * |
| 79 | * Use: Returns the next key in some arbitrary sequence. |
| 80 | */ |
| 81 | |
| 82 | key *key_next(key_iter *i) |
| 83 | { |
| 84 | hash_base *b; |
| 85 | key *k; |
| 86 | do { |
| 87 | HASH_NEXT(&i->i, b); |
| 88 | k = (key *)b; |
| 89 | } while (k && KEY_EXPIRED(i->t, k->exp) && KEY_EXPIRED(i->t, k->del)); |
| 90 | return (k); |
| 91 | } |
| 92 | |
| 93 | /*----- Lookup ------------------------------------------------------------*/ |
| 94 | |
| 95 | /* --- @key_bytype@ --- * |
| 96 | * |
| 97 | * Arguments: @key_file *f@ = key file we want a key from |
| 98 | * @const char *type@ = type string for desired key |
| 99 | * |
| 100 | * Returns: Pointer to the best key to use, or null. |
| 101 | * |
| 102 | * Use: Looks up a key by its type. Returns the key with the latest |
| 103 | * expiry time. This function will not return an expired key. |
| 104 | */ |
| 105 | |
| 106 | key *key_bytype(key_file *f, const char *type) |
| 107 | { |
| 108 | time_t now = time(0); |
| 109 | key *k; |
| 110 | key_ref *kr; |
| 111 | |
| 112 | if ((kr = sym_find(&f->bytype, type, -1, 0, 0)) == 0) |
| 113 | return (0); |
| 114 | for (k = kr->k; k && KEY_EXPIRED(now, k->exp); k = k->next) |
| 115 | ; |
| 116 | return (k); |
| 117 | } |
| 118 | |
| 119 | /* --- @key_byid@ --- * |
| 120 | * |
| 121 | * Arguments: @key_file *f@ = key file to find a key from |
| 122 | * @uint32 id@ = id to look for |
| 123 | * |
| 124 | * Returns: Key with matching id. |
| 125 | * |
| 126 | * Use: Returns a key given its id. This function will return an |
| 127 | * expired key, but not a deleted one. |
| 128 | */ |
| 129 | |
| 130 | key *key_byid(key_file *f, uint32 id) |
| 131 | { |
| 132 | time_t t = time(0); |
| 133 | hash_base **bin, *b; |
| 134 | |
| 135 | bin = HASH_BIN(&f->byid, id); |
| 136 | for (b = *bin; b; b = b->next) { |
| 137 | if (b->hash == id) { |
| 138 | key *k = (key *)b; |
| 139 | if (KEY_EXPIRED(t, k->exp) && KEY_EXPIRED(t, k->del)) |
| 140 | return (0); |
| 141 | return (k); |
| 142 | } |
| 143 | } |
| 144 | return (0); |
| 145 | } |
| 146 | |
| 147 | /* --- @key_bytag@ --- * |
| 148 | * |
| 149 | * Arguments: @key_file *f@ = key file to find a key from |
| 150 | * @const char *tag@ = pointer to tag string |
| 151 | * |
| 152 | * Returns: Key with matching id or tag. |
| 153 | * |
| 154 | * Use: Returns a key given its tag or id. This function will return |
| 155 | * an expired key, but not a deleted one. |
| 156 | */ |
| 157 | |
| 158 | key *key_bytag(key_file *f, const char *tag) |
| 159 | { |
| 160 | time_t t = time(0); |
| 161 | char *p; |
| 162 | uint32 id; |
| 163 | enum { GUESS = -1, TAG, ID, TYPE }; int lookup; |
| 164 | key_ref *kr; |
| 165 | key *k; |
| 166 | |
| 167 | if (STRNCMP(tag, ==, "tag:", 4)) { lookup = TAG; tag += 4; } |
| 168 | else if (STRNCMP(tag, ==, "id:", 3)) { lookup = ID; tag += 3; } |
| 169 | else if (STRNCMP(tag, ==, "type:", 5)) { lookup = TYPE; tag += 5; } |
| 170 | else lookup = GUESS; |
| 171 | |
| 172 | if ((lookup == GUESS || lookup == TAG) && |
| 173 | (kr = sym_find(&f->bytag, tag, -1, 0, 0)) != 0 && |
| 174 | !(KEY_EXPIRED(t, kr->k->exp) && KEY_EXPIRED(t, kr->k->del))) |
| 175 | return (kr->k); |
| 176 | |
| 177 | if (lookup == GUESS || lookup == ID) { |
| 178 | id = strtoul(tag, &p, 16); |
| 179 | if (!*p && (k = key_byid(f, id)) != 0) return (k); |
| 180 | } |
| 181 | |
| 182 | if ((lookup == GUESS || lookup == TYPE) && (k = key_bytype(f, tag)) != 0) |
| 183 | return (k); |
| 184 | |
| 185 | return (0); |
| 186 | } |
| 187 | |
| 188 | /* --- @key_qtag@ --- * |
| 189 | * |
| 190 | * Arguments: @key_file *f@ = key file to find a key from |
| 191 | * @const char *tag@ = pointer to tag string |
| 192 | * @dstr *d@ = pointer to string for full tag name |
| 193 | * @key **k@ = where to store the key pointer |
| 194 | * @key_data ***kd@ = where to store the key data pointer |
| 195 | * |
| 196 | * Returns: Zero if OK, nonzero if it failed. |
| 197 | * |
| 198 | * Use: Performs a full lookup on a qualified tag name. The tag is |
| 199 | * qualified by the names of subkeys, separated by dots. Hence, |
| 200 | * a qualified tag is ID|TAG[.TAG...]. The various result |
| 201 | * pointers can be null to indicate that the result isn't |
| 202 | * interesting. |
| 203 | */ |
| 204 | |
| 205 | int key_qtag(key_file *f, const char *tag, dstr *d, key **k, key_data ***kd) |
| 206 | { |
| 207 | dstr dd = DSTR_INIT; |
| 208 | const char *q; |
| 209 | key *kk; |
| 210 | key_data **kkd; |
| 211 | |
| 212 | /* --- Find the end of the base tag --- */ |
| 213 | |
| 214 | if ((q = strchr(tag, '.')) == 0) |
| 215 | DPUTS(&dd, tag); |
| 216 | else { |
| 217 | DPUTM(&dd, tag, q - tag); |
| 218 | DPUTZ(&dd); |
| 219 | q++; |
| 220 | } |
| 221 | |
| 222 | /* --- Look up the key tag --- */ |
| 223 | |
| 224 | if ((kk = key_bytag(f, dd.buf)) == 0) { |
| 225 | dstr_destroy(&dd); |
| 226 | return (-1); |
| 227 | } |
| 228 | |
| 229 | /* --- Set the various initial bits of result up --- */ |
| 230 | |
| 231 | if (d) |
| 232 | key_fulltag(kk, d); |
| 233 | if (k) |
| 234 | *k = kk; |
| 235 | kkd = &kk->k; |
| 236 | |
| 237 | /* --- Now dig through the rest of the tag --- */ |
| 238 | |
| 239 | if (q) { |
| 240 | while (*q) { |
| 241 | key_struct *ks; |
| 242 | |
| 243 | /* --- Stick on the next bit of the fullqtag --- */ |
| 244 | |
| 245 | DRESET(&dd); |
| 246 | while (*q && *q != '.') { |
| 247 | DPUTC(&dd, *q); |
| 248 | q++; |
| 249 | } |
| 250 | DPUTZ(&dd); |
| 251 | if (d) { |
| 252 | DPUTC(d, '.'); |
| 253 | DPUTD(d, &dd); |
| 254 | } |
| 255 | |
| 256 | /* --- Look up the subkey --- */ |
| 257 | |
| 258 | if ((*kkd)->e != KENC_STRUCT) { |
| 259 | kkd = 0; |
| 260 | break; |
| 261 | } |
| 262 | if ((ks = sym_find(&(*kkd)->u.s, dd.buf, -1, 0, 0)) == 0) { |
| 263 | kkd = 0; |
| 264 | break; |
| 265 | } |
| 266 | kkd = &ks->k; |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | /* --- Return the results --- */ |
| 271 | |
| 272 | dstr_destroy(&dd); |
| 273 | if (!kkd) |
| 274 | return (-1); |
| 275 | if (kd) |
| 276 | *kd = kkd; |
| 277 | return (0); |
| 278 | } |
| 279 | |
| 280 | /*----- Miscellaneous functions -------------------------------------------*/ |
| 281 | |
| 282 | /* --- @key_delete@ --- * |
| 283 | * |
| 284 | * Arguments: @key_file *f@ = pointer to file block |
| 285 | * @key *k@ = key to delete |
| 286 | * |
| 287 | * Returns: Error code (one of the @KERR@ constants). |
| 288 | * |
| 289 | * Use: Removes the given key from the list. The key file must be |
| 290 | * writable. (Due to the horridness of the data structures, |
| 291 | * deleted keys aren't actually removed, just marked so that |
| 292 | * they can't be looked up or iterated over. One upshot of |
| 293 | * this is that they don't get written back to the file when |
| 294 | * it's closed.) |
| 295 | */ |
| 296 | |
| 297 | int key_delete(key_file *f, key *k) |
| 298 | { |
| 299 | KEY_WRITE(f); |
| 300 | k->exp = KEXP_EXPIRE; |
| 301 | k->del = KEXP_EXPIRE; |
| 302 | KEY_MODIFY(f); |
| 303 | return (0); |
| 304 | } |
| 305 | |
| 306 | /* --- @key_expired@ --- * |
| 307 | * |
| 308 | * Arguments: @key *k@ = pointer to key block |
| 309 | * |
| 310 | * Returns: Zero if the key is OK, nonzero if it's expired. |
| 311 | */ |
| 312 | |
| 313 | int key_expired(key *k) |
| 314 | { |
| 315 | time_t now = time(0); |
| 316 | return (KEY_EXPIRED(now, k->exp) || KEY_EXPIRED(now, k->del)); |
| 317 | } |
| 318 | |
| 319 | /* --- @key_expire@ --- * |
| 320 | * |
| 321 | * Arguments: @key_file *f@ = pointer to file block |
| 322 | * @key *k@ = pointer to key block |
| 323 | * |
| 324 | * Returns: Error code (one of the @KERR@ constants). |
| 325 | * |
| 326 | * Use: Immediately marks the key as expired. It may be removed |
| 327 | * immediately, if it is no longer required, and will be removed |
| 328 | * by a tidy operation when it is no longer required. The key |
| 329 | * file must be writable. |
| 330 | */ |
| 331 | |
| 332 | int key_expire(key_file *f, key *k) |
| 333 | { |
| 334 | KEY_WRITE(f); |
| 335 | k->exp = KEXP_EXPIRE; |
| 336 | if (k->del == KEXP_FOREVER) |
| 337 | k->del = KEXP_EXPIRE; |
| 338 | KEY_MODIFY(f); |
| 339 | return (0); |
| 340 | } |
| 341 | |
| 342 | /* --- @key_used@ --- * |
| 343 | * |
| 344 | * Arguments: @key_file *f@ = pointer to key file |
| 345 | * @key *k@ = pointer to key block |
| 346 | * @time_t t@ = when key can be removed |
| 347 | * |
| 348 | * Returns: Zero if OK, nonzero on failure. |
| 349 | * |
| 350 | * Use: Marks a key as being required until a given time. Even |
| 351 | * though the key may expire before then (and won't be returned |
| 352 | * by type after that time), it will still be available when |
| 353 | * requested explicitly by id. The key file must be writable. |
| 354 | * |
| 355 | * The only (current) reason for failure is attempting to use |
| 356 | * a key which can expire for something which can't. |
| 357 | */ |
| 358 | |
| 359 | int key_used(key_file *f, key *k, time_t t) |
| 360 | { |
| 361 | KEY_WRITE(f); |
| 362 | if (t == KEXP_FOREVER) { |
| 363 | if (k->exp != KEXP_FOREVER) |
| 364 | return (KERR_WILLEXPIRE); |
| 365 | } else if (k->del >= t) |
| 366 | return (0); |
| 367 | |
| 368 | k->del = t; |
| 369 | KEY_MODIFY(f); |
| 370 | return (0); |
| 371 | } |
| 372 | |
| 373 | /* --- @key_fingerprint@ --- * |
| 374 | * |
| 375 | * Arguments: @key *k@ = the key to fingerprint |
| 376 | * @ghash *h@ = the hash to use |
| 377 | * @const key_filter *kf@ = filter to apply |
| 378 | * |
| 379 | * Returns: Nonzero if the key slightly matched the filter. |
| 380 | * |
| 381 | * Use: Updates the hash context with the key contents. |
| 382 | */ |
| 383 | |
| 384 | static int abyname(const void *a, const void *b) { |
| 385 | key_attr *const *x = a, *const *y = b; |
| 386 | return (strcmp(SYM_NAME(*x), SYM_NAME(*y))); |
| 387 | } |
| 388 | |
| 389 | int key_fingerprint(key *k, ghash *h, const key_filter *kf) |
| 390 | { |
| 391 | dstr d = DSTR_INIT; |
| 392 | int rc = 0; |
| 393 | key_attr *a, **v; |
| 394 | size_t n, i; |
| 395 | sym_iter ai; |
| 396 | |
| 397 | if (!key_encode(k->k, &d, kf)) |
| 398 | goto done; |
| 399 | rc = 1; |
| 400 | GH_HASHSTR(h, "catacomb-key-fingerprint:"); |
| 401 | GH_HASHU32(h, k->id); |
| 402 | GH_HASHSTR8(h, k->type); |
| 403 | GH_HASH(h, d.buf, d.len); |
| 404 | for (n = 0, sym_mkiter(&ai, &k->a); (a = sym_next(&ai)) != 0; n++); |
| 405 | if (n) { |
| 406 | v = xmalloc(n * sizeof(*v)); |
| 407 | for (i = 0, sym_mkiter(&ai, &k->a); (a = sym_next(&ai)) != 0; i++) |
| 408 | v[i] = a; |
| 409 | qsort(v, n, sizeof(*v), abyname); |
| 410 | for (i = 0; i < n; i++) { |
| 411 | GH_HASHSTR8(h, SYM_NAME(v[i])); |
| 412 | GH_HASHSTR16(h, v[i]->p); |
| 413 | } |
| 414 | xfree(v); |
| 415 | } |
| 416 | done: |
| 417 | dstr_destroy(&d); |
| 418 | return (rc); |
| 419 | } |
| 420 | |
| 421 | /*----- That's all, folks -------------------------------------------------*/ |