Commit | Line | Data |
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410c8acf | 1 | /* -*-c-*- |
2 | * | |
410c8acf | 3 | * Key loading and storing |
4 | * | |
5 | * (c) 2001 Straylight/Edgeware | |
6 | */ | |
7 | ||
e04c2d50 | 8 | /*----- Licensing notice --------------------------------------------------* |
410c8acf | 9 | * |
10 | * This file is part of Trivial IP Encryption (TrIPE). | |
11 | * | |
12 | * TrIPE is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2 of the License, or | |
15 | * (at your option) any later version. | |
e04c2d50 | 16 | * |
410c8acf | 17 | * TrIPE 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 General Public License for more details. | |
e04c2d50 | 21 | * |
410c8acf | 22 | * You should have received a copy of the GNU General Public License |
23 | * along with TrIPE; if not, write to the Free Software Foundation, | |
24 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
25 | */ | |
26 | ||
410c8acf | 27 | /*----- Header files ------------------------------------------------------*/ |
28 | ||
29 | #include "tripe.h" | |
30 | ||
52c03a2a | 31 | /*----- Key groups --------------------------------------------------------*/ |
32 | ||
799e58b9 MW |
33 | /* The key-loading functions here must fill in the kdata slot @g@ and |
34 | * either @kpriv@ or @kpub@ as appropriate. The caller will take care of | |
35 | * determining @kpub@ given a private key, and of ensuring that @kpriv@ is | |
36 | * null for a public key. | |
37 | */ | |
38 | ||
52c03a2a | 39 | typedef struct kgops { |
40 | const char *ty; | |
799e58b9 MW |
41 | int (*loadpriv)(key_data *, kdata *, dstr *, dstr *); |
42 | int (*loadpub)(key_data *, kdata *, dstr *, dstr *); | |
52c03a2a | 43 | } kgops; |
44 | ||
4155aec4 MW |
45 | /* --- @KLOAD@ --- * |
46 | * | |
47 | * Arguments: @ty@, @TY@ = key type name (lower- and upper-case) | |
48 | * @which@, @WHICH@ = `pub' or `priv' (and upper-case) | |
49 | * @setgroup@ = code to initialize @kd->g@ | |
50 | * @setpriv@ = code to initialize @kd->kpriv@ | |
51 | * @setpub@ = code to initialize @kd->kpub@ | |
52 | * | |
53 | * Use: Generates the body of one of the (rather tedious) key loading | |
54 | * functions. See the description of @KEYTYPES@ below for the | |
55 | * details. | |
56 | */ | |
52c03a2a | 57 | |
4155aec4 MW |
58 | #define KLOAD(ty, TY, which, WHICH, setgroup, setpriv, setpub) \ |
59 | static int kg##ty##_##which(key_data *d, kdata *kd, dstr *t, dstr *e) \ | |
60 | { \ | |
61 | key_packstruct kps[TY##_##WHICH##FETCHSZ]; \ | |
62 | key_packdef *kp; \ | |
63 | ty##_##which p; \ | |
64 | int rc; \ | |
65 | \ | |
66 | /* --- Initialize things we've not set up yet --- */ \ | |
67 | \ | |
68 | kd->g = 0; kd->kpub = 0; \ | |
69 | \ | |
70 | /* --- Unpack the key --- */ \ | |
71 | \ | |
72 | kp = key_fetchinit(ty##_##which##fetch, kps, &p); \ | |
73 | if ((rc = key_unpack(kp, d, t)) != 0) { \ | |
74 | a_format(e, "unpack-failed", "%s", key_strerror(rc), A_END); \ | |
75 | goto fail; \ | |
76 | } \ | |
77 | \ | |
78 | /* --- Extract the pieces of the key --- */ \ | |
79 | \ | |
80 | setgroup; \ | |
81 | setpriv; \ | |
82 | kd->kpub = G_CREATE(kd->g); \ | |
83 | setpub; \ | |
84 | \ | |
85 | /* --- We win --- */ \ | |
86 | \ | |
87 | rc = 0; \ | |
88 | goto done; \ | |
89 | \ | |
90 | fail: \ | |
91 | if (kd->kpub) G_DESTROY(kd->g, kd->kpub); \ | |
92 | if (kd->g) G_DESTROYGROUP(kd->g); \ | |
93 | rc = -1; \ | |
94 | \ | |
95 | done: \ | |
96 | key_fetchdone(kp); \ | |
97 | return (rc); \ | |
52c03a2a | 98 | } |
99 | ||
4155aec4 MW |
100 | /* --- @KEYTYPES@ --- * |
101 | * | |
102 | * A list of the various key types, and how to unpack them. Each entry in | |
103 | * the list has the form | |
104 | * | |
105 | * _(ty, TY, setgroup, setpriv, setpub) | |
106 | * | |
107 | * The @ty@ and @TY@ are lower- and upper-case versions of the key type name, | |
108 | * and there should be @key_fetchdef@s called @ty_{priv,pub}fetch@. | |
109 | * | |
110 | * The @setgroup@, @setpriv@ and @setpub@ items are code fragments which are | |
111 | * passed to @KLOAD@ to build appropriate key-loading methods. By the time | |
112 | * these code fragments are run, the key has been unpacked from the incoming | |
113 | * key data using @ty_whichfetch@ into a @ty_which@ structure named @p@. | |
114 | * They can report errors by writing an appropriate token sequence to @e@ and | |
115 | * jumping to @fail@. | |
116 | */ | |
52c03a2a | 117 | |
4155aec4 MW |
118 | #define KEYTYPES(_) \ |
119 | \ | |
120 | /* --- Diffie-Hellman --- */ \ | |
121 | \ | |
122 | _(dh, DH, \ | |
123 | { kd->g = group_prime(&p.dp); }, \ | |
124 | { kd->kpriv = MP_COPY(p.x); }, \ | |
125 | { if (G_FROMINT(kd->g, kd->kpub, p.y)) { \ | |
126 | a_format(e, "bad-public-vector", A_END); \ | |
127 | goto fail; \ | |
128 | } \ | |
129 | }) \ | |
130 | \ | |
131 | /* --- Elliptic curves --- */ \ | |
132 | \ | |
133 | _(ec, EC, \ | |
134 | { ec_info ei; const char *err; \ | |
135 | if ((err = ec_getinfo(&ei, p.cstr)) != 0) { \ | |
136 | a_format(e, "decode-failed", "%s", err, A_END); \ | |
137 | goto fail; \ | |
138 | } \ | |
139 | kd->g = group_ec(&ei); \ | |
140 | }, \ | |
141 | { kd->kpriv = MP_COPY(p.x); }, \ | |
142 | { if (G_FROMEC(kd->g, kd->kpub, &p.p)) { \ | |
143 | a_format(e, "bad-public-vector", A_END); \ | |
144 | goto fail; \ | |
145 | } \ | |
146 | }) | |
147 | ||
148 | #define KEYTYPE_DEF(ty, TY, setgroup, setpriv, setpub) \ | |
149 | KLOAD(ty, TY, priv, PRIV, setgroup, setpriv, \ | |
150 | { G_EXP(kd->g, kd->kpub, kd->g->g, kd->kpriv); }) \ | |
151 | KLOAD(ty, TY, pub, PUB, setgroup, { }, setpub) \ | |
152 | static const kgops kg##ty##_ops = { #ty, kg##ty##_priv, kg##ty##_pub }; | |
153 | KEYTYPES(KEYTYPE_DEF) | |
52c03a2a | 154 | |
155 | /* --- Table of supported key types --- */ | |
156 | ||
4155aec4 MW |
157 | static const kgops *kgtab[] = { |
158 | #define KEYTYPE_ENTRY(ty, TY, setgroup, setpriv, setpub) &kg##ty##_ops, | |
159 | KEYTYPES(KEYTYPE_ENTRY) | |
160 | #undef KEYTYPE_ENTRY | |
161 | 0 | |
162 | }; | |
52c03a2a | 163 | |
b5c45da1 | 164 | /*----- Algswitch stuff ---------------------------------------------------*/ |
165 | ||
166 | /* --- @algs_get@ --- * | |
167 | * | |
168 | * Arguments: @algswitch *a@ = where to put the algorithms | |
4d36660a MW |
169 | * @dstr *e@ = where to write errror tokens |
170 | * @key_file *kf@ = key file | |
b5c45da1 | 171 | * @key *k@ = key to inspect |
172 | * | |
4d36660a | 173 | * Returns: Zero if OK; nonzero on error. |
b5c45da1 | 174 | * |
175 | * Use: Extracts an algorithm choice from a key. | |
176 | */ | |
177 | ||
4d36660a | 178 | static int algs_get(algswitch *a, dstr *e, key_file *kf, key *k) |
b5c45da1 | 179 | { |
180 | const char *p; | |
4d36660a | 181 | char *q, *qq; |
b5c45da1 | 182 | dstr d = DSTR_INIT; |
4d36660a | 183 | int rc = -1; |
b5c45da1 | 184 | |
4d36660a | 185 | /* --- Symmetric encryption for bulk data --- */ |
b5c45da1 | 186 | |
4d36660a MW |
187 | if ((p = key_getattr(kf, k, "cipher")) == 0) p = "blowfish-cbc"; |
188 | if ((a->c = gcipher_byname(p)) == 0) { | |
189 | a_format(e, "unknown-cipher", "%s", p, A_END); | |
190 | goto done; | |
191 | } | |
192 | ||
193 | /* --- Hash function --- */ | |
194 | ||
195 | if ((p = key_getattr(kf, k, "hash")) == 0) p = "rmd160"; | |
196 | if ((a->h = ghash_byname(p)) == 0) { | |
197 | a_format(e, "unknown-hash", "%s", p, A_END); | |
198 | goto done; | |
199 | } | |
b5c45da1 | 200 | |
4d36660a | 201 | /* --- Symmetric encryption for key derivation --- */ |
b5c45da1 | 202 | |
74ee77cb | 203 | if ((p = key_getattr(kf, k, "mgf")) == 0) { |
b5c45da1 | 204 | dstr_reset(&d); |
74ee77cb | 205 | dstr_putf(&d, "%s-mgf", a->h->name); |
b5c45da1 | 206 | p = d.buf; |
207 | } | |
4d36660a MW |
208 | if ((a->mgf = gcipher_byname(p)) == 0) { |
209 | a_format(e, "unknown-mgf-cipher", "%s", p, A_END); | |
210 | goto done; | |
211 | } | |
212 | ||
213 | /* --- Message authentication for bulk data --- */ | |
b5c45da1 | 214 | |
215 | if ((p = key_getattr(kf, k, "mac")) != 0) { | |
216 | dstr_reset(&d); | |
217 | dstr_puts(&d, p); | |
218 | if ((q = strchr(d.buf, '/')) != 0) | |
219 | *q++ = 0; | |
4d36660a MW |
220 | if ((a->m = gmac_byname(d.buf)) == 0) { |
221 | a_format(e, "unknown-mac", "%s", d.buf, A_END); | |
222 | goto done; | |
223 | } | |
b5c45da1 | 224 | if (!q) |
225 | a->tagsz = a->m->hashsz; | |
226 | else { | |
4d36660a MW |
227 | unsigned long n = strtoul(q, &qq, 0); |
228 | if (*qq) { | |
229 | a_format(e, "bad-tag-length-string", "%s", q, A_END); | |
230 | goto done; | |
231 | } | |
232 | if (n%8 || n/8 > a->m->hashsz) { | |
233 | a_format(e, "bad-tag-length", "%lu", n, A_END); | |
234 | goto done; | |
235 | } | |
b5c45da1 | 236 | a->tagsz = n/8; |
237 | } | |
238 | } else { | |
239 | dstr_reset(&d); | |
240 | dstr_putf(&d, "%s-hmac", a->h->name); | |
4d36660a MW |
241 | if ((a->m = gmac_byname(d.buf)) == 0) { |
242 | a_format(e, "no-hmac-for-hash", "%s", a->h->name, A_END); | |
243 | goto done; | |
244 | } | |
b5c45da1 | 245 | a->tagsz = a->h->hashsz/2; |
246 | } | |
247 | ||
4d36660a | 248 | rc = 0; |
b5c45da1 | 249 | done: |
250 | dstr_destroy(&d); | |
4d36660a | 251 | return (rc); |
b5c45da1 | 252 | } |
253 | ||
254 | /* --- @algs_check@ --- * | |
255 | * | |
256 | * Arguments: @algswitch *a@ = a choice of algorithms | |
4d36660a | 257 | * @dstr *e@ = where to write error tokens |
b5c45da1 | 258 | * @const group *g@ = the group we're working in |
259 | * | |
4d36660a | 260 | * Returns: Zero if OK; nonzero on error. |
b5c45da1 | 261 | * |
262 | * Use: Checks an algorithm choice for sensibleness. This also | |
263 | * derives some useful information from the choices, and you | |
264 | * must call this before committing the algorithm selection | |
265 | * for use by @keyset@ functions. | |
266 | */ | |
267 | ||
4d36660a | 268 | static int algs_check(algswitch *a, dstr *e, const group *g) |
b5c45da1 | 269 | { |
270 | /* --- Derive the key sizes --- * | |
271 | * | |
272 | * Must ensure that we have non-empty keys. This isn't ideal, but it | |
383a9d71 MW |
273 | * provides a handy sanity check. Also must be based on a 64- or 128-bit |
274 | * block cipher or we can't do the data expiry properly. | |
b5c45da1 | 275 | */ |
276 | ||
277 | a->hashsz = a->h->hashsz; | |
4d36660a MW |
278 | if ((a->cksz = keysz(a->hashsz, a->c->keysz)) == 0) { |
279 | a_format(e, "cipher", "%s", a->c->name, | |
280 | "no-key-size", "%lu", (unsigned long)a->hashsz, | |
281 | A_END); | |
282 | return (-1); | |
283 | } | |
284 | if ((a->mksz = keysz(a->hashsz, a->m->keysz)) == 0) { | |
285 | a_format(e, "mac", "%s", a->m->name, | |
286 | "no-key-size", "%lu", (unsigned long)a->hashsz, | |
287 | A_END); | |
288 | return (-1); | |
289 | } | |
b5c45da1 | 290 | |
383a9d71 MW |
291 | /* --- Derive the data limit --- */ |
292 | ||
293 | if (a->c->blksz < 16) a->expsz = MEG(64); | |
294 | else a->expsz = MEG(2048); | |
295 | ||
b5c45da1 | 296 | /* --- Ensure the MGF accepts hashes as keys --- */ |
297 | ||
4d36660a MW |
298 | if (keysz(a->hashsz, a->mgf->keysz) != a->hashsz) { |
299 | a_format(e, "mgf", "%s", a->mgf->name, | |
300 | "restrictive-key-schedule", | |
301 | A_END); | |
302 | return (-1); | |
303 | } | |
b5c45da1 | 304 | |
305 | /* --- All ship-shape and Bristol-fashion --- */ | |
306 | ||
307 | return (0); | |
308 | } | |
309 | ||
799e58b9 | 310 | /* --- @km_samealgsp@ --- * |
b5c45da1 | 311 | * |
799e58b9 | 312 | * Arguments: @const kdata *kdx, *kdy@ = two key data objects |
b5c45da1 | 313 | * |
799e58b9 | 314 | * Returns: Nonzero if their two algorithm selections are the same. |
b5c45da1 | 315 | * |
316 | * Use: Checks sameness of algorithm selections: used to ensure that | |
317 | * peers are using sensible algorithms. | |
318 | */ | |
319 | ||
799e58b9 | 320 | int km_samealgsp(const kdata *kdx, const kdata *kdy) |
b5c45da1 | 321 | { |
799e58b9 MW |
322 | const algswitch *a = &kdx->algs, *aa = &kdy->algs; |
323 | ||
324 | return (group_samep(kdx->g, kdy->g) && a->c == aa->c && | |
325 | a->mgf == aa->mgf && a->h == aa->h && | |
b5c45da1 | 326 | a->m == aa->m && a->tagsz == aa->tagsz); |
327 | } | |
328 | ||
799e58b9 MW |
329 | /*----- Key data and key nodes --------------------------------------------*/ |
330 | ||
331 | typedef struct keyhalf { | |
332 | const char *kind; | |
333 | int (*load)(const kgops *, key_data *, kdata *, dstr *, dstr *); | |
334 | const char *kr; | |
335 | key_file *kf; | |
336 | fwatch w; | |
337 | sym_table tab; | |
338 | } keyhalf; | |
339 | ||
340 | /* --- @kh_loadpub@, @kh_loadpriv@ --- * | |
341 | * | |
342 | * Arguments: @const kgops *ko@ = key-group operations for key type | |
343 | * @key_data *d@ = key data object as stored in keyring | |
344 | * @kdata *kd@ = our key-data object to fill in | |
345 | * @dstr *t@ = the key tag name | |
346 | * @dstr *e@ = a string to write error tokens to | |
347 | * | |
348 | * Returns: Zero on success, @-1@ on error. | |
349 | * | |
350 | * Use: These functions handle the main difference between public and | |
351 | * private key halves. They are responsible for setting @g@, | |
352 | * @kpriv@ and @kpub@ appropriately in all keys, handling the | |
353 | * mismatch between the largely half-indifferent calling code | |
354 | * and the group-specific loading functions. | |
355 | * | |
356 | * The function @kh_loadpriv@ is also responsible for checking | |
357 | * the group for goodness. We don't bother checking public | |
358 | * keys, because each public key we actually end up using must | |
359 | * share a group with a private key which we'll already have | |
360 | * checked. | |
361 | */ | |
362 | ||
363 | static int kh_loadpub(const kgops *ko, key_data *d, kdata *kd, | |
364 | dstr *t, dstr *e) | |
365 | { | |
366 | int rc; | |
367 | ||
368 | if ((rc = ko->loadpub(d, kd, t, e)) != 0) | |
369 | goto fail_0; | |
370 | if (group_check(kd->g, kd->kpub)) { | |
73174919 | 371 | a_format(e, "bad-public-group-element", A_END); |
799e58b9 MW |
372 | goto fail_1; |
373 | } | |
374 | kd->kpriv = 0; | |
375 | return (0); | |
376 | ||
377 | fail_1: | |
378 | G_DESTROY(kd->g, kd->kpub); | |
379 | G_DESTROYGROUP(kd->g); | |
380 | fail_0: | |
381 | return (-1); | |
382 | } | |
383 | ||
384 | static int kh_loadpriv(const kgops *ko, key_data *d, kdata *kd, | |
385 | dstr *t, dstr *e) | |
386 | { | |
387 | int rc; | |
388 | const char *err; | |
389 | ||
390 | if ((rc = ko->loadpriv(d, kd, t, e)) != 0) | |
391 | goto fail_0; | |
392 | if ((err = G_CHECK(kd->g, &rand_global)) != 0) { | |
393 | a_format(e, "bad-group", "%s", err, A_END); | |
394 | goto fail_1; | |
395 | } | |
799e58b9 MW |
396 | return (0); |
397 | ||
398 | fail_1: | |
399 | mp_drop(kd->kpriv); | |
4155aec4 | 400 | G_DESTROY(kd->g, kd->kpub); |
799e58b9 MW |
401 | G_DESTROYGROUP(kd->g); |
402 | fail_0: | |
403 | return (-1); | |
404 | } | |
405 | ||
406 | static struct keyhalf | |
407 | priv = { "private", kh_loadpriv }, | |
408 | pub = { "public", kh_loadpub }; | |
410c8acf | 409 | |
410 | /* --- @keymoan@ --- * | |
411 | * | |
56814747 | 412 | * Arguments: @const char *file@ = name of the file |
e04c2d50 MW |
413 | * @int line@ = line number in file |
414 | * @const char *msg@ = error message | |
4d36660a | 415 | * @void *p@ = argument pointer (indicates which keyring) |
410c8acf | 416 | * |
e04c2d50 | 417 | * Returns: --- |
410c8acf | 418 | * |
e04c2d50 | 419 | * Use: Reports an error message about loading a key file. |
410c8acf | 420 | */ |
421 | ||
422 | static void keymoan(const char *file, int line, const char *msg, void *p) | |
f43df819 | 423 | { |
799e58b9 | 424 | keyhalf *kh = p; |
4d36660a MW |
425 | |
426 | if (!line) { | |
799e58b9 | 427 | a_warn("KEYMGMT", "%s-keyring", kh->kind, "%s", file, |
4d36660a MW |
428 | "io-error", "?ERRNO", A_END); |
429 | } else { | |
799e58b9 | 430 | a_warn("KEYMGMT", "%s-keyring", kh->kind, "%s", file, "line", "%d", line, |
4d36660a MW |
431 | "%s", msg, A_END); |
432 | } | |
f43df819 | 433 | } |
410c8acf | 434 | |
799e58b9 | 435 | /* --- @kh_reopen@ --- * |
fc5f4823 | 436 | * |
799e58b9 | 437 | * Arguments: @keyhalf *kh@ = pointer to keyhalf structure |
fc5f4823 | 438 | * |
799e58b9 | 439 | * Returns: Zero on success, @-1@ on error. |
fc5f4823 | 440 | * |
799e58b9 MW |
441 | * Use: Reopens the key file for the appropriate key half. If this |
442 | * fails, everything is left as it was; if it succeeds, then the | |
443 | * old file is closed (if it was non-null) and the new one put | |
444 | * in its place. | |
fc5f4823 MW |
445 | */ |
446 | ||
799e58b9 | 447 | static int kh_reopen(keyhalf *kh) |
fc5f4823 | 448 | { |
799e58b9 | 449 | key_file *kf = CREATE(key_file); |
fc5f4823 | 450 | |
799e58b9 MW |
451 | if (key_open(kf, kh->kr, KOPEN_READ, keymoan, kh)) { |
452 | a_warn("KEYMGMT", "%s-keyring", kh->kind, "%s", kh->kr, | |
7f81b1b4 | 453 | "io-error", "?ERRNO", A_END); |
799e58b9 MW |
454 | DESTROY(kf); |
455 | return (-1); | |
456 | } else { | |
457 | if (kh->kf) { | |
458 | key_close(kh->kf); | |
459 | DESTROY(kh->kf); | |
460 | } | |
461 | kh->kf = kf; | |
462 | return (0); | |
463 | } | |
464 | } | |
fc5f4823 | 465 | |
799e58b9 MW |
466 | /* --- @kh_init@ --- * |
467 | * | |
468 | * Arguments: @keyhalf *kh@ = pointer to keyhalf structure to set up | |
469 | * @const char *kr@ = name of the keyring file | |
470 | * | |
471 | * Returns: --- | |
472 | * | |
473 | * Use: Initialize a keyhalf structure, maintaining the private or | |
474 | * public keys. Intended to be called during initialization: | |
475 | * exits if there's some kind of problem. | |
476 | */ | |
fc5f4823 | 477 | |
799e58b9 MW |
478 | static void kh_init(keyhalf *kh, const char *kr) |
479 | { | |
480 | kh->kr = kr; | |
481 | fwatch_init(&kh->w, kr); | |
482 | sym_create(&kh->tab); | |
483 | kh->kf = 0; | |
484 | ||
485 | if (kh_reopen(kh)) | |
486 | die(EXIT_FAILURE, "failed to load %s keyring `%s'", kh->kind, kr); | |
fc5f4823 MW |
487 | } |
488 | ||
799e58b9 | 489 | /* --- @kh_load@ --- * |
410c8acf | 490 | * |
799e58b9 MW |
491 | * Arguments: @keyhalf *kh@ = pointer to keyhalf |
492 | * @const char *tag@ = key tag to be loaded | |
493 | * @int complainp@ = whether to complain about missing keys | |
410c8acf | 494 | * |
799e58b9 MW |
495 | * Returns: Pointer to a @kdata@ structure if successful, or null on |
496 | * failure. | |
410c8acf | 497 | * |
799e58b9 MW |
498 | * Use: Attempts to load a key from the current key file. This |
499 | * function always reads data from the file: it's used when | |
500 | * there's a cache miss from @kh_find@, and when refreshing the | |
501 | * known keys in @kh_refresh@. The returned kdata has a | |
502 | * reference count of exactly 1, and has no home knode. | |
410c8acf | 503 | */ |
504 | ||
799e58b9 | 505 | static kdata *kh_load(keyhalf *kh, const char *tag, int complainp) |
410c8acf | 506 | { |
52c03a2a | 507 | dstr t = DSTR_INIT; |
4d36660a | 508 | dstr e = DSTR_INIT; |
799e58b9 MW |
509 | key *k; |
510 | key_data **d; | |
511 | kdata *kd; | |
512 | const char *ty; | |
513 | const kgops **ko; | |
52c03a2a | 514 | |
799e58b9 | 515 | /* --- Find the key and grab its tag --- */ |
52c03a2a | 516 | |
799e58b9 MW |
517 | if (key_qtag(kh->kf, tag, &t, &k, &d)) { |
518 | if (complainp) { | |
519 | a_warn("KEYMGMT", "%s-keyring", kh->kind, "%s", kh->kr, | |
520 | "key-not-found", "%s", tag, A_END); | |
521 | } | |
522 | goto fail_0; | |
52c03a2a | 523 | } |
524 | ||
799e58b9 MW |
525 | /* --- Find the key's group type and the appropriate operations --- * |
526 | * | |
527 | * There are several places to look for the key type. The most obvious is | |
528 | * the `kx-group' key attribute. But there's also the key type itself, for | |
529 | * compatibility reasons. | |
530 | */ | |
52c03a2a | 531 | |
799e58b9 MW |
532 | ty = key_getattr(kh->kf, k, "kx-group"); |
533 | if (!ty && strncmp(k->type, "tripe-", 6) == 0) ty = k->type + 6; | |
534 | if (!ty) ty = "dh"; | |
52c03a2a | 535 | |
799e58b9 MW |
536 | for (ko = kgtab; *ko; ko++) |
537 | if (strcmp((*ko)->ty, ty) == 0) goto foundko; | |
538 | a_warn("KEYMGMT", "%s-keyring", kh->kind, | |
539 | "%s", kh->kr, "key", "%s", t.buf, | |
540 | "unknown-group-type", "%s", ty, A_END); | |
541 | goto fail_0; | |
542 | ||
543 | foundko: | |
544 | kd = CREATE(kdata); | |
545 | if (kh->load(*ko, *d, kd, &t, &e)) { | |
546 | a_warn("KEYMGMT", "%s-keyring", kh->kind, | |
547 | "%s", kh->kr, "key" "%s", t.buf, | |
4d36660a | 548 | "*%s", e.buf, A_END); |
799e58b9 | 549 | goto fail_1; |
52c03a2a | 550 | } |
551 | ||
799e58b9 MW |
552 | if (algs_get(&kd->algs, &e, kh->kf, k) || |
553 | (kd->kpriv && algs_check(&kd->algs, &e, kd->g))) { | |
554 | a_warn("KEYMGMT", "%s-keyring", kh->kind, | |
555 | "%s", kh->kr, "key", "%s", t.buf, | |
4d36660a | 556 | "*%s", e.buf, A_END); |
799e58b9 | 557 | goto fail_2; |
410c8acf | 558 | } |
52c03a2a | 559 | |
799e58b9 MW |
560 | kd->tag = xstrdup(t.buf); |
561 | kd->indexsz = mp_octets(kd->g->r); | |
562 | kd->ref = 1; | |
563 | kd->kn = 0; | |
564 | kd->t_exp = k->exp; | |
52c03a2a | 565 | |
566 | IF_TRACING(T_KEYMGMT, { | |
799e58b9 | 567 | trace(T_KEYMGMT, "keymgmt: loaded %s key `%s'", kh->kind, t.buf); |
52c03a2a | 568 | IF_TRACING(T_CRYPTO, { |
799e58b9 MW |
569 | trace(T_CRYPTO, "crypto: r = %s", mpstr(kd->g->r)); |
570 | trace(T_CRYPTO, "crypto: h = %s", mpstr(kd->g->h)); | |
571 | if (kd->kpriv) | |
572 | trace(T_CRYPTO, "crypto: x = %s", mpstr(kd->kpriv)); | |
573 | trace(T_CRYPTO, "crypto: cipher = %s", kd->algs.c->name); | |
574 | trace(T_CRYPTO, "crypto: mgf = %s", kd->algs.mgf->name); | |
575 | trace(T_CRYPTO, "crypto: hash = %s", kd->algs.h->name); | |
b5c45da1 | 576 | trace(T_CRYPTO, "crypto: mac = %s/%lu", |
799e58b9 | 577 | kd->algs.m->name, (unsigned long)kd->algs.tagsz * 8); |
52c03a2a | 578 | }) |
579 | }) | |
580 | ||
799e58b9 | 581 | goto done; |
52c03a2a | 582 | |
799e58b9 MW |
583 | fail_2: |
584 | if (kd->kpriv) mp_drop(kd->kpriv); | |
585 | G_DESTROY(kd->g, kd->kpub); | |
586 | G_DESTROYGROUP(kd->g); | |
587 | fail_1: | |
588 | DESTROY(kd); | |
589 | fail_0: | |
590 | kd = 0; | |
591 | done: | |
52c03a2a | 592 | dstr_destroy(&t); |
4d36660a | 593 | dstr_destroy(&e); |
799e58b9 | 594 | return (kd); |
410c8acf | 595 | } |
596 | ||
799e58b9 | 597 | /* --- @kh_find@ --- * |
410c8acf | 598 | * |
799e58b9 MW |
599 | * Arguments: @keyhalf *kh@ = pointer to the keyhalf |
600 | * @const char *tag@ = key to be obtained | |
601 | * @int complainp@ = whether to complain about missing keys | |
410c8acf | 602 | * |
799e58b9 | 603 | * Returns: A pointer to the kdata, or null on error. |
410c8acf | 604 | * |
799e58b9 MW |
605 | * Use: Obtains kdata, maybe from the cache. This won't update a |
606 | * stale cache entry, though @kh_refresh@ ought to have done | |
607 | * that already. The returned kdata object may be shared with | |
608 | * other users. (One of this function's responsibilities, over | |
609 | * @kh_load@, is to set the home knode of a freshly loaded | |
610 | * kdata.) | |
410c8acf | 611 | */ |
612 | ||
799e58b9 | 613 | static kdata *kh_find(keyhalf *kh, const char *tag, int complainp) |
410c8acf | 614 | { |
799e58b9 MW |
615 | knode *kn; |
616 | kdata *kd; | |
617 | unsigned f; | |
410c8acf | 618 | |
799e58b9 MW |
619 | kn = sym_find(&kh->tab, tag, -1, sizeof(knode), &f); |
620 | ||
621 | if (f) { | |
622 | if (kn->f & KNF_BROKEN) { | |
623 | T( if (complainp) | |
624 | trace(T_KEYMGMT, "keymgmt: key `%s' marked as broken", tag); ) | |
625 | return (0); | |
626 | } | |
627 | ||
628 | kd = kn->kd; | |
629 | if (kd) kd->ref++; | |
630 | T( trace(T_KEYMGMT, "keymgmt: %scache hit for key `%s'", | |
631 | kd ? "" : "negative ", tag); ) | |
632 | return (kd); | |
633 | } else { | |
634 | kd = kh_load(kh, tag, complainp); | |
635 | kn->kd = kd; | |
636 | kn->kh = kh; | |
637 | kn->f = 0; | |
638 | if (!kd) | |
639 | kn->f |= KNF_BROKEN; | |
640 | else { | |
641 | kd->kn = kn; | |
642 | kd->ref++; | |
643 | } | |
644 | return (kd); | |
410c8acf | 645 | } |
410c8acf | 646 | } |
647 | ||
799e58b9 | 648 | /* --- @kh_refresh@ --- * |
410c8acf | 649 | * |
799e58b9 | 650 | * Arguments: @keyhalf *kh@ = pointer to the keyhalf |
410c8acf | 651 | * |
799e58b9 MW |
652 | * Returns: Zero if nothing needs to be done; nonzero if peers should |
653 | * refresh their keys. | |
410c8acf | 654 | * |
799e58b9 MW |
655 | * Use: Refreshes cached keys from files. |
656 | * | |
657 | * Each active knode is examined to see if a new key is | |
658 | * available: the return value is nonzero if any new keys are. | |
659 | * A key is considered new if its algorithms, public key, or | |
660 | * expiry time are/is different. | |
661 | * | |
662 | * Stub knodes (with no kdata attached) are removed, so that a | |
663 | * later retry can succeed if the file has been fixed. (This | |
664 | * doesn't count as a change, since no peers should be relying | |
665 | * on a nonexistent key.) | |
410c8acf | 666 | */ |
667 | ||
799e58b9 | 668 | static int kh_refresh(keyhalf *kh) |
410c8acf | 669 | { |
799e58b9 MW |
670 | knode *kn; |
671 | kdata *kd; | |
672 | sym_iter i; | |
673 | int changep = 0; | |
674 | ||
675 | if (!fwatch_update(&kh->w, kh->kr) || kh_reopen(kh)) | |
676 | return (0); | |
677 | ||
678 | T( trace(T_KEYMGMT, "keymgmt: rescan %s keyring `%s'", kh->kind, kh->kr); ) | |
679 | for (sym_mkiter(&i, &kh->tab); (kn = sym_next(&i)) != 0; ) { | |
680 | if (!kn->kd) { | |
681 | T( trace(T_KEYMGMT, "keymgmt: discard stub entry for key `%s'", | |
682 | SYM_NAME(kn)); ) | |
683 | sym_remove(&kh->tab, kn); | |
684 | continue; | |
685 | } | |
686 | if ((kd = kh_load(kh, SYM_NAME(kn), 1)) == 0) { | |
687 | if (!(kn->f & KNF_BROKEN)) { | |
688 | T( trace(T_KEYMGMT, "keymgmt: failed to load new key `%s': " | |
689 | "marking it as broken", | |
690 | SYM_NAME(kn)); ) | |
691 | kn->f |= KNF_BROKEN; | |
692 | } | |
693 | continue; | |
694 | } | |
695 | kn->f &= ~KNF_BROKEN; | |
696 | if (kd->t_exp == kn->kd->t_exp && | |
697 | km_samealgsp(kd, kn->kd) && | |
698 | G_EQ(kd->g, kd->kpub, kn->kd->kpub)) { | |
699 | T( trace(T_KEYMGMT, "keymgmt: key `%s' unchanged", SYM_NAME(kn)); ) | |
700 | continue; | |
701 | } | |
702 | T( trace(T_KEYMGMT, "keymgmt: loaded new version of key `%s'", | |
703 | SYM_NAME(kn)); ) | |
704 | km_unref(kn->kd); | |
705 | kd->kn = kn; | |
706 | kn->kd = kd; | |
707 | changep = 1; | |
708 | } | |
410c8acf | 709 | |
799e58b9 MW |
710 | return (changep); |
711 | } | |
410c8acf | 712 | |
799e58b9 | 713 | /*----- Main code ---------------------------------------------------------*/ |
410c8acf | 714 | |
799e58b9 MW |
715 | const char *tag_priv; |
716 | kdata *master; | |
410c8acf | 717 | |
410c8acf | 718 | /* --- @km_init@ --- * |
719 | * | |
799e58b9 MW |
720 | * Arguments: @const char *privkr@ = private keyring file |
721 | * @const char *pubkr@ = public keyring file | |
722 | * @const char *ptag@ = default private-key tag | |
410c8acf | 723 | * |
724 | * Returns: --- | |
725 | * | |
799e58b9 MW |
726 | * Use: Initializes the key-management machinery, loading the |
727 | * keyrings and so on. | |
410c8acf | 728 | */ |
729 | ||
799e58b9 | 730 | void km_init(const char *privkr, const char *pubkr, const char *ptag) |
410c8acf | 731 | { |
b5c45da1 | 732 | const gchash *const *hh; |
410c8acf | 733 | |
b5c45da1 | 734 | for (hh = ghashtab; *hh; hh++) { |
735 | if ((*hh)->hashsz > MAXHASHSZ) { | |
736 | die(EXIT_FAILURE, "INTERNAL ERROR: %s hash length %lu > MAXHASHSZ %d", | |
737 | (*hh)->name, (unsigned long)(*hh)->hashsz, MAXHASHSZ); | |
738 | } | |
739 | } | |
740 | ||
799e58b9 MW |
741 | kh_init(&priv, privkr); |
742 | kh_init(&pub, pubkr); | |
743 | ||
744 | tag_priv = ptag; | |
745 | if ((master = km_findpriv(ptag)) == 0) exit(EXIT_FAILURE); | |
410c8acf | 746 | } |
747 | ||
799e58b9 | 748 | /* --- @km_reload@ --- * |
410c8acf | 749 | * |
799e58b9 | 750 | * Arguments: --- |
410c8acf | 751 | * |
799e58b9 | 752 | * Returns: Zero if OK, nonzero to force reloading of keys. |
410c8acf | 753 | * |
799e58b9 | 754 | * Use: Checks the keyrings to see if they need reloading. |
410c8acf | 755 | */ |
756 | ||
799e58b9 | 757 | int km_reload(void) |
410c8acf | 758 | { |
799e58b9 MW |
759 | int changep = 0; |
760 | kdata *kd; | |
761 | ||
762 | if (kh_refresh(&priv)) { | |
763 | changep = 1; | |
764 | kd = master->kn->kd; | |
35c8b547 | 765 | if (kd != master) { |
799e58b9 MW |
766 | km_unref(master); |
767 | km_ref(kd); | |
768 | master = kd; | |
769 | } | |
770 | } | |
771 | if (kh_refresh(&pub)) | |
772 | changep = 1; | |
773 | return (changep); | |
774 | } | |
52c03a2a | 775 | |
799e58b9 MW |
776 | /* --- @km_findpub@, @km_findpriv@ --- * |
777 | * | |
778 | * Arguments: @const char *tag@ = key tag to load | |
779 | * | |
780 | * Returns: Pointer to the kdata object if successful, or null on error. | |
781 | * | |
782 | * Use: Fetches a public or private key from the keyring. | |
783 | */ | |
52c03a2a | 784 | |
799e58b9 | 785 | kdata *km_findpub(const char *tag) { return (kh_find(&pub, tag, 1)); } |
410c8acf | 786 | |
799e58b9 MW |
787 | kdata *km_findpriv(const char *tag) |
788 | { | |
789 | kdata *kd; | |
52c03a2a | 790 | |
799e58b9 MW |
791 | /* Unpleasantness for the sake of compatibility. */ |
792 | if (!tag && (kd = kh_find(&priv, "tripe", 0)) != 0) return (kd); | |
793 | else return (kh_find(&priv, tag ? tag : "tripe-dh", 1)); | |
794 | } | |
52c03a2a | 795 | |
799e58b9 MW |
796 | /* --- @km_tag@ --- * |
797 | * | |
798 | * Arguments: @kdata *kd@ - pointer to the kdata object | |
799 | * | |
800 | * Returns: A pointer to the short tag by which the kdata was loaded. | |
801 | */ | |
52c03a2a | 802 | |
799e58b9 | 803 | const char *km_tag(kdata *kd) { return (SYM_NAME(kd->kn)); } |
52c03a2a | 804 | |
799e58b9 MW |
805 | /* --- @km_ref@ --- * |
806 | * | |
807 | * Arguments: @kdata *kd@ = pointer to the kdata object | |
808 | * | |
809 | * Returns: --- | |
810 | * | |
811 | * Use: Claim a new reference to a kdata object. | |
812 | */ | |
52c03a2a | 813 | |
799e58b9 | 814 | void km_ref(kdata *kd) { kd->ref++; } |
52c03a2a | 815 | |
799e58b9 MW |
816 | /* --- @km_unref@ --- * |
817 | * | |
818 | * Arguments: @kdata *kd@ = pointer to the kdata object | |
819 | * | |
820 | * Returns: --- | |
821 | * | |
822 | * Use: Releases a reference to a kdata object. | |
823 | */ | |
52c03a2a | 824 | |
799e58b9 MW |
825 | void km_unref(kdata *kd) |
826 | { | |
827 | if (--kd->ref) return; | |
828 | if (kd->kpriv) mp_drop(kd->kpriv); | |
829 | G_DESTROY(kd->g, kd->kpub); | |
830 | xfree(kd->tag); | |
831 | G_DESTROYGROUP(kd->g); | |
832 | } | |
833 | ||
410c8acf | 834 | /*----- That's all, folks -------------------------------------------------*/ |