| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: key-misc.c,v 1.2 2000/02/12 18:21:02 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 1.2 2000/02/12 18:21:02 mdw |
| 34 | * Overhaul of key management (again). |
| 35 | * |
| 36 | * Revision 1.1 1999/12/22 15:47:48 mdw |
| 37 | * Major key-management revision. |
| 38 | * |
| 39 | */ |
| 40 | |
| 41 | /*----- Header files ------------------------------------------------------*/ |
| 42 | |
| 43 | #include <stdio.h> |
| 44 | #include <stdlib.h> |
| 45 | #include <string.h> |
| 46 | #include <time.h> |
| 47 | |
| 48 | #include <mLib/bits.h> |
| 49 | #include <mLib/hash.h> |
| 50 | #include <mLib/sub.h> |
| 51 | #include <mLib/sym.h> |
| 52 | |
| 53 | #include "key.h" |
| 54 | |
| 55 | /*----- Useful macros -----------------------------------------------------*/ |
| 56 | |
| 57 | #define KEY_WRITE(f) do { \ |
| 58 | if (!(f)->f & KF_WRITE) \ |
| 59 | return (KERR_READONLY); \ |
| 60 | } while (0) |
| 61 | |
| 62 | #define KEY_MODIFY(f) do { (f)->f |= KF_MODIFIED; } while (0) |
| 63 | |
| 64 | #define KEY_LOAD(n) ((n) * 2) |
| 65 | |
| 66 | /*----- Iteration and iterators -------------------------------------------*/ |
| 67 | |
| 68 | /* --- @key_mkiter@ --- * |
| 69 | * |
| 70 | * Arguments: @key_iter *i@ = pointer to iterator object |
| 71 | * @key_file *f@ = pointer to file structure |
| 72 | * |
| 73 | * Returns: --- |
| 74 | * |
| 75 | * Use: Initializes a key iterator. The keys are returned by |
| 76 | * @key_next@. |
| 77 | */ |
| 78 | |
| 79 | void key_mkiter(key_iter *i, key_file *f) |
| 80 | { |
| 81 | HASH_MKITER(&i->i, &f->byid); |
| 82 | i->t = time(0); |
| 83 | } |
| 84 | |
| 85 | /* --- @key_next@ --- * |
| 86 | * |
| 87 | * Arguments: @key_iter *i@ = pointer to iterator object |
| 88 | * |
| 89 | * Returns: Pointer to next key, or null. |
| 90 | * |
| 91 | * Use: Returns the next key in some arbitrary sequence. |
| 92 | */ |
| 93 | |
| 94 | key *key_next(key_iter *i) |
| 95 | { |
| 96 | hash_base *b; |
| 97 | key *k; |
| 98 | do { |
| 99 | HASH_NEXT(&i->i, b); |
| 100 | k = (key *)b; |
| 101 | } while (k && KEY_EXPIRED(i->t, k->exp) && KEY_EXPIRED(i->t, k->del)); |
| 102 | return (k); |
| 103 | } |
| 104 | |
| 105 | /*----- Lookup ------------------------------------------------------------*/ |
| 106 | |
| 107 | /* --- @key_bytype@ --- * |
| 108 | * |
| 109 | * Arguments: @key_file *f@ = key file we want a key from |
| 110 | * @const char *type@ = type string for desired key |
| 111 | * |
| 112 | * Returns: Pointer to the best key to use, or null. |
| 113 | * |
| 114 | * Use: Looks up a key by its type. Returns the key with the latest |
| 115 | * expiry time. This function will not return an expired key. |
| 116 | */ |
| 117 | |
| 118 | key *key_bytype(key_file *f, const char *type) |
| 119 | { |
| 120 | time_t now = time(0); |
| 121 | key *k; |
| 122 | key_ref *kr; |
| 123 | |
| 124 | if ((kr = sym_find(&f->bytype, type, -1, 0, 0)) == 0) |
| 125 | return (0); |
| 126 | for (k = kr->k; k && KEY_EXPIRED(now, k->exp); k = k->next) |
| 127 | ; |
| 128 | return (k); |
| 129 | } |
| 130 | |
| 131 | /* --- @key_byid@ --- * |
| 132 | * |
| 133 | * Arguments: @key_file *f@ = key file to find a key from |
| 134 | * @uint32 id@ = id to look for |
| 135 | * |
| 136 | * Returns: Key with matching id. |
| 137 | * |
| 138 | * Use: Returns a key given its id. This function will return an |
| 139 | * expired key, but not a deleted one. |
| 140 | */ |
| 141 | |
| 142 | key *key_byid(key_file *f, uint32 id) |
| 143 | { |
| 144 | time_t t = time(0); |
| 145 | hash_base **bin, *b; |
| 146 | |
| 147 | bin = HASH_BIN(&f->byid, id); |
| 148 | for (b = *bin; b; b = b->next) { |
| 149 | if (b->hash == id) { |
| 150 | key *k = (key *)b; |
| 151 | if (KEY_EXPIRED(t, k->exp) && KEY_EXPIRED(t, k->del)) |
| 152 | return (0); |
| 153 | return (k); |
| 154 | } |
| 155 | } |
| 156 | return (0); |
| 157 | } |
| 158 | |
| 159 | /* --- @key_bytag@ --- * |
| 160 | * |
| 161 | * Arguments: @key_file *f@ = key file to find a key from |
| 162 | * @const char *tag@ = pointer to tag string |
| 163 | * |
| 164 | * Returns: Key with matching id or tag. |
| 165 | * |
| 166 | * Use: Returns a key given its tag or id. This function will return |
| 167 | * an expired key, but not a deleted one. |
| 168 | */ |
| 169 | |
| 170 | key *key_bytag(key_file *f, const char *tag) |
| 171 | { |
| 172 | time_t t = time(0); |
| 173 | char *p; |
| 174 | uint32 id; |
| 175 | key_ref *kr = sym_find(&f->bytag, tag, -1, 0, 0); |
| 176 | |
| 177 | if (kr && !(KEY_EXPIRED(t, kr->k->exp) && KEY_EXPIRED(t, kr->k->exp))) |
| 178 | return (kr->k); |
| 179 | id = strtoul(tag, &p, 16); |
| 180 | if (!*p) |
| 181 | return (key_byid(f, id)); |
| 182 | return (key_bytype(f, tag)); |
| 183 | } |
| 184 | |
| 185 | /* --- @key_qtag@ --- * |
| 186 | * |
| 187 | * Arguments: @key_file *f@ = key file to find a key from |
| 188 | * @const char *tag@ = pointer to tag string |
| 189 | * @dstr *d@ = pointer to string for full tag name |
| 190 | * @key **k@ = where to store the key pointer |
| 191 | * @key_data **kd@ = where to store the key data pointer |
| 192 | * |
| 193 | * Returns: Zero if OK, nonzero if it failed. |
| 194 | * |
| 195 | * Use: Performs a full lookup on a qualified tag name. The tag is |
| 196 | * qualified by the names of subkeys, separated by dots. Hence, |
| 197 | * a qualified tag is ID|TAG[.TAG...]. The various result |
| 198 | * pointers can be null to indicate that the result isn't |
| 199 | * interesting. |
| 200 | */ |
| 201 | |
| 202 | int key_qtag(key_file *f, const char *tag, dstr *d, key **k, key_data **kd) |
| 203 | { |
| 204 | dstr dd = DSTR_INIT; |
| 205 | const char *q; |
| 206 | key *kk; |
| 207 | key_data *kkd; |
| 208 | |
| 209 | /* --- Find the end of the base tag --- */ |
| 210 | |
| 211 | if ((q = strchr(tag, '.')) == 0) |
| 212 | DPUTS(&dd, tag); |
| 213 | else { |
| 214 | DPUTM(&dd, tag, q - tag); |
| 215 | DPUTZ(&dd); |
| 216 | q++; |
| 217 | } |
| 218 | |
| 219 | /* --- Look up the key tag --- */ |
| 220 | |
| 221 | if ((kk = key_bytag(f, dd.buf)) == 0) { |
| 222 | dstr_destroy(&dd); |
| 223 | return (-1); |
| 224 | } |
| 225 | |
| 226 | /* --- Set the various initial bits of result up --- */ |
| 227 | |
| 228 | if (d) |
| 229 | key_fulltag(kk, d); |
| 230 | if (k) |
| 231 | *k = kk; |
| 232 | kkd = &kk->k; |
| 233 | |
| 234 | /* --- Now dig through the rest of the tag --- */ |
| 235 | |
| 236 | while (q && *q) { |
| 237 | |
| 238 | /* --- Stick on the next bit of the fullqtag --- */ |
| 239 | |
| 240 | DRESET(&dd); |
| 241 | while (*q && *q != '.') { |
| 242 | DPUTC(&dd, *q); |
| 243 | q++; |
| 244 | } |
| 245 | DPUTZ(&dd); |
| 246 | if (d) { |
| 247 | DPUTC(d, '.'); |
| 248 | DPUTD(d, &dd); |
| 249 | } |
| 250 | |
| 251 | /* --- Look up the subkey --- */ |
| 252 | |
| 253 | if (kkd->e != KENC_STRUCT) { |
| 254 | kkd = 0; |
| 255 | break; |
| 256 | } |
| 257 | if ((kkd = key_structfind(kkd, dd.buf)) == 0) |
| 258 | break; |
| 259 | } |
| 260 | |
| 261 | /* --- Return the results --- */ |
| 262 | |
| 263 | if (!kkd) |
| 264 | return (-1); |
| 265 | dstr_destroy(&dd); |
| 266 | if (kd) |
| 267 | *kd = kkd; |
| 268 | return (0); |
| 269 | } |
| 270 | |
| 271 | /*----- Miscellaneous functions -------------------------------------------*/ |
| 272 | |
| 273 | /* --- @key_delete@ --- * |
| 274 | * |
| 275 | * Arguments: @key_file *f@ = pointer to file block |
| 276 | * @key *k@ = key to delete |
| 277 | * |
| 278 | * Returns: Error code (one of the @KERR@ constants). |
| 279 | * |
| 280 | * Use: Removes the given key from the list. The key file must be |
| 281 | * writable. (Due to the horridness of the data structures, |
| 282 | * deleted keys aren't actually removed, just marked so that |
| 283 | * they can't be looked up or iterated over. One upshot of |
| 284 | * this is that they don't get written back to the file when |
| 285 | * it's closed.) |
| 286 | */ |
| 287 | |
| 288 | int key_delete(key_file *f, key *k) |
| 289 | { |
| 290 | KEY_WRITE(f); |
| 291 | k->exp = KEXP_EXPIRE; |
| 292 | k->del = KEXP_EXPIRE; |
| 293 | KEY_MODIFY(f); |
| 294 | return (0); |
| 295 | } |
| 296 | |
| 297 | /* --- @key_expire@ --- * |
| 298 | * |
| 299 | * Arguments: @key_file *f@ = pointer to file block |
| 300 | * @key *k@ = pointer to key block |
| 301 | * |
| 302 | * Returns: Error code (one of the @KERR@ constants). |
| 303 | * |
| 304 | * Use: Immediately marks the key as expired. It may be removed |
| 305 | * immediately, if it is no longer required, and will be removed |
| 306 | * by a tidy operation when it is no longer required. The key |
| 307 | * file must be writable. |
| 308 | */ |
| 309 | |
| 310 | int key_expire(key_file *f, key *k) |
| 311 | { |
| 312 | KEY_WRITE(f); |
| 313 | k->exp = KEXP_EXPIRE; |
| 314 | if (k->del == KEXP_FOREVER) |
| 315 | k->del = KEXP_EXPIRE; |
| 316 | KEY_MODIFY(f); |
| 317 | return (0); |
| 318 | } |
| 319 | |
| 320 | /* --- @key_used@ --- * |
| 321 | * |
| 322 | * Arguments: @key_file *f@ = pointer to key file |
| 323 | * @key *k@ = pointer to key block |
| 324 | * @time_t t@ = when key can be removed |
| 325 | * |
| 326 | * Returns: Zero if OK, nonzero on failure. |
| 327 | * |
| 328 | * Use: Marks a key as being required until a given time. Even |
| 329 | * though the key may expire before then (and won't be returned |
| 330 | * by type after that time), it will still be available when |
| 331 | * requested explicitly by id. The key file must be writable. |
| 332 | * |
| 333 | * The only (current) reason for failure is attempting to use |
| 334 | * a key which can expire for something which can't. |
| 335 | */ |
| 336 | |
| 337 | int key_used(key_file *f, key *k, time_t t) |
| 338 | { |
| 339 | KEY_WRITE(f); |
| 340 | if (t == KEXP_FOREVER) { |
| 341 | if (k->exp != KEXP_FOREVER) |
| 342 | return (KERR_WILLEXPIRE); |
| 343 | } else if (k->del >= t) |
| 344 | return (0); |
| 345 | |
| 346 | k->del = t; |
| 347 | KEY_MODIFY(f); |
| 348 | return (0); |
| 349 | } |
| 350 | |
| 351 | /*----- That's all, folks -------------------------------------------------*/ |