Commit | Line | Data |
---|---|---|
5c3f75ec | 1 | /* -*-c-*- |
2 | * | |
c65df279 | 3 | * $Id$ |
5c3f75ec | 4 | * |
5 | * Catcrypt key-encapsulation | |
6 | * | |
7 | * (c) 2004 Straylight/Edgeware | |
8 | */ | |
9 | ||
45c0fd36 | 10 | /*----- Licensing notice --------------------------------------------------* |
5c3f75ec | 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. | |
45c0fd36 | 18 | * |
5c3f75ec | 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. | |
45c0fd36 | 23 | * |
5c3f75ec | 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 | /*----- Header files ------------------------------------------------------*/ | |
31 | ||
cd6eca43 MW |
32 | #define _FILE_OFFSET_BITS 64 |
33 | ||
5c3f75ec | 34 | #include <stdlib.h> |
35 | ||
36 | #include <mLib/alloc.h> | |
37 | #include <mLib/dstr.h> | |
38 | #include <mLib/report.h> | |
39 | #include <mLib/sub.h> | |
40 | ||
41 | #include "mprand.h" | |
42 | #include "rand.h" | |
43 | ||
44 | #include "ec.h" | |
45 | #include "ec-keys.h" | |
46 | #include "dh.h" | |
47 | #include "rsa.h" | |
48 | ||
49 | #include "rmd160.h" | |
50 | #include "blowfish-cbc.h" | |
51 | ||
52 | #include "cc.h" | |
53 | ||
54 | /*----- Key encapsulation -------------------------------------------------*/ | |
55 | ||
56 | /* --- RSA --- */ | |
57 | ||
58 | typedef struct rsa_encctx { | |
59 | kem k; | |
60 | rsa_pubctx rp; | |
61 | } rsa_encctx; | |
62 | ||
63 | static kem *rsa_encinit(key *k, void *kd) | |
64 | { | |
65 | rsa_encctx *re = CREATE(rsa_encctx); | |
66 | rsa_pubcreate(&re->rp, kd); | |
67 | return (&re->k); | |
68 | } | |
69 | ||
70 | static int rsa_encdoit(kem *k, dstr *d, ghash *h) | |
71 | { | |
72 | rsa_encctx *re = (rsa_encctx *)k; | |
73 | mp *x = mprand_range(MP_NEW, re->rp.rp->n, &rand_global, 0); | |
74 | mp *y = rsa_pubop(&re->rp, MP_NEW, x); | |
75 | size_t n = mp_octets(re->rp.rp->n); | |
76 | dstr_ensure(d, n); | |
77 | mp_storeb(x, d->buf, n); | |
78 | GH_HASH(h, d->buf, n); | |
79 | mp_storeb(y, d->buf, n); | |
80 | d->len += n; | |
81 | mp_drop(x); | |
82 | mp_drop(y); | |
83 | return (0); | |
84 | } | |
85 | ||
86 | static const char *rsa_lengthcheck(mp *n) | |
87 | { | |
88 | if (mp_bits(n) < 1020) return ("key too short"); | |
89 | return (0); | |
90 | } | |
91 | ||
92 | static const char *rsa_enccheck(kem *k) | |
93 | { | |
94 | rsa_encctx *re = (rsa_encctx *)k; | |
95 | const char *e; | |
96 | if ((e = rsa_lengthcheck(re->rp.rp->n)) != 0) return (e); | |
97 | return (0); | |
98 | } | |
99 | ||
100 | static void rsa_encdestroy(kem *k) | |
101 | { | |
102 | rsa_encctx *re = (rsa_encctx *)k; | |
103 | rsa_pubdestroy(&re->rp); | |
104 | DESTROY(re); | |
105 | } | |
106 | ||
107 | static const kemops rsa_encops = { | |
108 | rsa_pubfetch, sizeof(rsa_pub), | |
109 | rsa_encinit, rsa_encdoit, rsa_enccheck, rsa_encdestroy | |
110 | }; | |
111 | ||
112 | typedef struct rsa_decctx { | |
113 | kem k; | |
114 | rsa_privctx rp; | |
115 | } rsa_decctx; | |
116 | ||
117 | static kem *rsa_decinit(key *k, void *kd) | |
118 | { | |
119 | rsa_decctx *rd = CREATE(rsa_decctx); | |
120 | rsa_privcreate(&rd->rp, kd, &rand_global); | |
121 | return (&rd->k); | |
122 | } | |
123 | ||
124 | static int rsa_decdoit(kem *k, dstr *d, ghash *h) | |
125 | { | |
126 | rsa_decctx *rd = (rsa_decctx *)k; | |
127 | mp *x = mp_loadb(MP_NEW, d->buf, d->len); | |
128 | size_t n; | |
129 | char *p; | |
130 | ||
131 | if (MP_CMP(x, >=, rd->rp.rp->n)) { | |
132 | mp_drop(x); | |
133 | return (-1); | |
134 | } | |
135 | n = mp_octets(rd->rp.rp->n); | |
136 | p = xmalloc(n); | |
137 | x = rsa_privop(&rd->rp, x, x); | |
138 | mp_storeb(x, p, n); | |
139 | GH_HASH(h, p, n); | |
140 | mp_drop(x); | |
141 | xfree(p); | |
142 | return (0); | |
143 | } | |
144 | ||
145 | static const char *rsa_deccheck(kem *k) | |
146 | { | |
147 | rsa_decctx *rd = (rsa_decctx *)k; | |
148 | const char *e; | |
149 | if ((e = rsa_lengthcheck(rd->rp.rp->n)) != 0) return (e); | |
150 | return (0); | |
151 | } | |
152 | ||
153 | static void rsa_decdestroy(kem *k) | |
154 | { | |
155 | rsa_decctx *rd = (rsa_decctx *)k; | |
156 | rsa_privdestroy(&rd->rp); | |
157 | DESTROY(rd); | |
158 | } | |
159 | ||
160 | static const kemops rsa_decops = { | |
161 | rsa_privfetch, sizeof(rsa_priv), | |
162 | rsa_decinit, rsa_decdoit, rsa_deccheck, rsa_decdestroy | |
163 | }; | |
164 | ||
165 | /* --- DH and EC --- */ | |
166 | ||
167 | typedef struct dh_encctx { | |
168 | kem k; | |
169 | group *g; | |
170 | mp *x; | |
171 | ge *y; | |
172 | } dh_encctx; | |
173 | ||
45c0fd36 | 174 | static dh_encctx *dh_doinit(key *k, const gprime_param *gp, mp *y, |
3688eb75 | 175 | group *(*makegroup)(const gprime_param *), |
176 | const char *what) | |
5c3f75ec | 177 | { |
178 | dh_encctx *de = CREATE(dh_encctx); | |
179 | dstr t = DSTR_INIT; | |
180 | ||
181 | key_fulltag(k, &t); | |
3688eb75 | 182 | if ((de->g = makegroup(gp)) == 0) |
183 | die(EXIT_FAILURE, "bad %s group in key `%s'", what, t.buf); | |
5c3f75ec | 184 | de->x = MP_NEW; |
185 | de->y = G_CREATE(de->g); | |
186 | if (G_FROMINT(de->g, de->y, y)) | |
187 | die(EXIT_FAILURE, "bad public key `%s'", t.buf); | |
188 | dstr_destroy(&t); | |
189 | return (de); | |
190 | } | |
191 | ||
192 | static dh_encctx *ec_doinit(key *k, const char *cstr, const ec *y) | |
193 | { | |
194 | dh_encctx *de = CREATE(dh_encctx); | |
195 | ec_info ei; | |
196 | const char *e; | |
197 | dstr t = DSTR_INIT; | |
198 | ||
199 | key_fulltag(k, &t); | |
200 | if ((e = ec_getinfo(&ei, cstr)) != 0 || | |
201 | (de->g = group_ec(&ei)) == 0) | |
202 | die(EXIT_FAILURE, "bad elliptic curve spec in key `%s': %s", t.buf, e); | |
203 | de->x = MP_NEW; | |
204 | de->y = G_CREATE(de->g); | |
205 | if (G_FROMEC(de->g, de->y, y)) | |
206 | die(EXIT_FAILURE, "bad public curve point `%s'", t.buf); | |
207 | dstr_destroy(&t); | |
208 | return (de); | |
209 | } | |
210 | ||
211 | static kem *dh_encinit(key *k, void *kd) | |
212 | { | |
213 | dh_pub *dp = kd; | |
3688eb75 | 214 | dh_encctx *de = dh_doinit(k, &dp->dp, dp->y, group_prime, "prime"); |
215 | return (&de->k); | |
216 | } | |
217 | ||
218 | static kem *bindh_encinit(key *k, void *kd) | |
219 | { | |
220 | dh_pub *dp = kd; | |
221 | dh_encctx *de = dh_doinit(k, &dp->dp, dp->y, group_binary, "binary"); | |
5c3f75ec | 222 | return (&de->k); |
223 | } | |
224 | ||
225 | static kem *ec_encinit(key *k, void *kd) | |
226 | { | |
227 | ec_pub *ep = kd; | |
228 | dh_encctx *de = ec_doinit(k, ep->cstr, &ep->p); | |
229 | return (&de->k); | |
230 | } | |
231 | ||
232 | static int dh_encdoit(kem *k, dstr *d, ghash *h) | |
233 | { | |
234 | dh_encctx *de = (dh_encctx *)k; | |
235 | mp *r = mprand_range(MP_NEW, de->g->r, &rand_global, 0); | |
236 | ge *x = G_CREATE(de->g); | |
237 | ge *y = G_CREATE(de->g); | |
238 | size_t n = de->g->noctets; | |
239 | buf b; | |
45c0fd36 | 240 | |
5c3f75ec | 241 | G_EXP(de->g, x, de->g->g, r); |
242 | G_EXP(de->g, y, de->y, r); | |
243 | dstr_ensure(d, n); | |
244 | buf_init(&b, d->buf, n); | |
245 | G_TORAW(de->g, &b, y); | |
246 | GH_HASH(h, BBASE(&b), BLEN(&b)); | |
247 | buf_init(&b, d->buf, n); | |
248 | G_TORAW(de->g, &b, x); | |
249 | GH_HASH(h, BBASE(&b), BLEN(&b)); | |
250 | d->len += BLEN(&b); | |
251 | mp_drop(r); | |
252 | G_DESTROY(de->g, x); | |
253 | G_DESTROY(de->g, y); | |
254 | return (0); | |
255 | } | |
256 | ||
257 | static const char *dh_enccheck(kem *k) | |
258 | { | |
259 | dh_encctx *de = (dh_encctx *)k; | |
260 | const char *e; | |
261 | if ((e = G_CHECK(de->g, &rand_global)) != 0) | |
262 | return (0); | |
263 | if (group_check(de->g, de->y)) | |
264 | return ("public key not in subgroup"); | |
265 | return (0); | |
266 | } | |
267 | ||
268 | static void dh_encdestroy(kem *k) | |
269 | { | |
270 | dh_encctx *de = (dh_encctx *)k; | |
271 | G_DESTROY(de->g, de->y); | |
272 | mp_drop(de->x); | |
273 | G_DESTROYGROUP(de->g); | |
6f313264 | 274 | DESTROY(de); |
5c3f75ec | 275 | } |
276 | ||
277 | static const kemops dh_encops = { | |
278 | dh_pubfetch, sizeof(dh_pub), | |
279 | dh_encinit, dh_encdoit, dh_enccheck, dh_encdestroy | |
280 | }; | |
281 | ||
3688eb75 | 282 | static const kemops bindh_encops = { |
283 | dh_pubfetch, sizeof(dh_pub), | |
284 | bindh_encinit, dh_encdoit, dh_enccheck, dh_encdestroy | |
285 | }; | |
286 | ||
5c3f75ec | 287 | static const kemops ec_encops = { |
288 | ec_pubfetch, sizeof(ec_pub), | |
289 | ec_encinit, dh_encdoit, dh_enccheck, dh_encdestroy | |
290 | }; | |
291 | ||
292 | static kem *dh_decinit(key *k, void *kd) | |
293 | { | |
294 | dh_priv *dp = kd; | |
3688eb75 | 295 | dh_encctx *de = dh_doinit(k, &dp->dp, dp->y, group_prime, "prime"); |
296 | de->x = MP_COPY(dp->x); | |
297 | return (&de->k); | |
298 | } | |
299 | ||
300 | static kem *bindh_decinit(key *k, void *kd) | |
301 | { | |
302 | dh_priv *dp = kd; | |
303 | dh_encctx *de = dh_doinit(k, &dp->dp, dp->y, group_binary, "binary"); | |
5c3f75ec | 304 | de->x = MP_COPY(dp->x); |
305 | return (&de->k); | |
306 | } | |
307 | ||
308 | static kem *ec_decinit(key *k, void *kd) | |
309 | { | |
310 | ec_priv *ep = kd; | |
311 | dh_encctx *de = ec_doinit(k, ep->cstr, &ep->p); | |
312 | de->x = MP_COPY(ep->x); | |
313 | return (&de->k); | |
314 | } | |
315 | ||
316 | static int dh_decdoit(kem *k, dstr *d, ghash *h) | |
317 | { | |
318 | dh_encctx *de = (dh_encctx *)k; | |
319 | ge *x = G_CREATE(de->g); | |
320 | size_t n = de->g->noctets; | |
321 | void *p = xmalloc(n); | |
322 | buf b; | |
323 | int rc = -1; | |
324 | ||
325 | buf_init(&b, d->buf, d->len); | |
326 | if (G_FROMRAW(de->g, &b, x) || group_check(de->g, x)) | |
327 | goto done; | |
328 | G_EXP(de->g, x, x, de->x); | |
329 | buf_init(&b, p, n); | |
330 | G_TORAW(de->g, &b, x); | |
331 | GH_HASH(h, BBASE(&b), BLEN(&b)); | |
332 | GH_HASH(h, d->buf, d->len); | |
333 | rc = 0; | |
334 | done: | |
335 | G_DESTROY(de->g, x); | |
336 | xfree(p); | |
337 | return (rc); | |
338 | } | |
339 | ||
340 | static const kemops dh_decops = { | |
341 | dh_privfetch, sizeof(dh_priv), | |
342 | dh_decinit, dh_decdoit, dh_enccheck, dh_encdestroy | |
343 | }; | |
344 | ||
3688eb75 | 345 | static const kemops bindh_decops = { |
346 | dh_privfetch, sizeof(dh_priv), | |
347 | bindh_decinit, dh_decdoit, dh_enccheck, dh_encdestroy | |
348 | }; | |
349 | ||
5c3f75ec | 350 | static const kemops ec_decops = { |
351 | ec_privfetch, sizeof(ec_priv), | |
352 | ec_decinit, dh_decdoit, dh_enccheck, dh_encdestroy | |
353 | }; | |
354 | ||
02dfbd5b MW |
355 | /* --- Symmetric --- */ |
356 | ||
357 | typedef struct symm_ctx { | |
358 | kem k; | |
359 | key_packdef kp; | |
360 | key_bin kb; | |
361 | } symm_ctx; | |
362 | ||
363 | static kem *symm_init(key *k, void *kd) | |
364 | { | |
365 | symm_ctx *s; | |
366 | dstr d = DSTR_INIT; | |
367 | int err; | |
368 | ||
369 | s = CREATE(symm_ctx); | |
370 | ||
371 | key_fulltag(k, &d); | |
372 | s->kp.e = KENC_BINARY; | |
373 | s->kp.p = &s->kb; | |
374 | s->kp.kd = 0; | |
375 | ||
376 | if ((err = key_unpack(&s->kp, kd, &d)) != 0) { | |
377 | die(EXIT_FAILURE, "failed to unpack symmetric key `%s': %s", | |
378 | d.buf, key_strerror(err)); | |
379 | } | |
380 | dstr_destroy(&d); | |
381 | return (&s->k); | |
382 | } | |
383 | ||
384 | static int symm_decdoit(kem *k, dstr *d, ghash *h) | |
385 | { | |
386 | symm_ctx *s = (symm_ctx *)k; | |
387 | ||
388 | GH_HASH(h, s->kb.k, s->kb.sz); | |
389 | GH_HASH(h, d->buf, d->len); | |
390 | return (0); | |
391 | } | |
392 | ||
393 | static int symm_encdoit(kem *k, dstr *d, ghash *h) | |
394 | { | |
395 | dstr_ensure(d, h->ops->c->hashsz); | |
396 | d->len += h->ops->c->hashsz; | |
397 | rand_get(RAND_GLOBAL, d->buf, d->len); | |
398 | return (symm_decdoit(k, d, h)); | |
399 | } | |
400 | ||
401 | static const char *symm_check(kem *k) { return (0); } | |
402 | ||
403 | static void symm_destroy(kem *k) | |
404 | { symm_ctx *s = (symm_ctx *)k; key_unpackdone(&s->kp); } | |
405 | ||
406 | static const kemops symm_encops = { | |
407 | 0, 0, | |
408 | symm_init, symm_encdoit, symm_check, symm_destroy | |
409 | }; | |
410 | ||
411 | static const kemops symm_decops = { | |
412 | 0, 0, | |
413 | symm_init, symm_decdoit, symm_check, symm_destroy | |
414 | }; | |
415 | ||
5c3f75ec | 416 | /* --- The switch table --- */ |
417 | ||
c65df279 | 418 | const struct kemtab kemtab[] = { |
5c3f75ec | 419 | { "rsa", &rsa_encops, &rsa_decops }, |
420 | { "dh", &dh_encops, &dh_decops }, | |
3688eb75 | 421 | { "bindh", &bindh_encops, &bindh_decops }, |
5c3f75ec | 422 | { "ec", &ec_encops, &ec_decops }, |
02dfbd5b | 423 | { "symm", &symm_encops, &symm_decops }, |
5c3f75ec | 424 | { 0, 0, 0 } |
425 | }; | |
426 | ||
427 | /* --- @getkem@ --- * | |
428 | * | |
429 | * Arguments: @key *k@ = the key to load | |
430 | * @const char *app@ = application name | |
431 | * @int wantpriv@ = nonzero if we want to decrypt | |
432 | * | |
433 | * Returns: A key-encapsulating thing. | |
434 | * | |
435 | * Use: Loads a key. | |
436 | */ | |
437 | ||
438 | kem *getkem(key *k, const char *app, int wantpriv) | |
439 | { | |
440 | const char *kalg, *halg = 0, *calg = 0; | |
441 | dstr d = DSTR_INIT; | |
442 | dstr t = DSTR_INIT; | |
443 | size_t n; | |
444 | char *p = 0; | |
445 | const char *q; | |
446 | kem *kk; | |
447 | const struct kemtab *kt; | |
448 | const kemops *ko; | |
449 | void *kd; | |
450 | int e; | |
451 | key_packdef *kp; | |
452 | ||
453 | /* --- Setup stuff --- */ | |
454 | ||
455 | key_fulltag(k, &t); | |
456 | ||
457 | /* --- Get the KEM name --- * | |
458 | * | |
459 | * Take the attribute if it's there; otherwise use the key type. | |
460 | */ | |
461 | ||
462 | n = strlen(app); | |
463 | if ((q = key_getattr(0, k, "kem")) != 0) { | |
464 | dstr_puts(&d, q); | |
465 | p = d.buf; | |
466 | } else if (strncmp(k->type, app, n) == 0 && k->type[n] == '-') { | |
467 | dstr_puts(&d, k->type); | |
468 | p = d.buf + n + 1; | |
469 | } else | |
470 | die(EXIT_FAILURE, "no KEM for key `%s'", t.buf); | |
471 | kalg = p; | |
472 | ||
473 | /* --- Grab the encryption scheme --- * | |
474 | * | |
475 | * Grab it from the KEM if it's there, but override it from the attribute. | |
476 | */ | |
477 | ||
478 | if (p && (p = strchr(p, '/')) != 0) { | |
479 | *p++ = 0; | |
480 | calg = p; | |
481 | } | |
482 | if ((q = key_getattr(0, k, "cipher")) != 0) | |
483 | calg = q; | |
484 | ||
485 | /* --- Grab the hash function --- */ | |
486 | ||
487 | if (p && (p = strchr(p, '/')) != 0) { | |
488 | *p++ = 0; | |
489 | halg = p; | |
490 | } | |
491 | if ((q = key_getattr(0, k, "hash")) != 0) | |
492 | halg = q; | |
493 | ||
494 | /* --- Instantiate the KEM --- */ | |
495 | ||
496 | for (kt = kemtab; kt->name; kt++) { | |
497 | if (strcmp(kt->name, kalg) == 0) | |
498 | goto k_found; | |
499 | } | |
500 | die(EXIT_FAILURE, "key encapsulation mechanism `%s' not found in key `%s'", | |
501 | kalg, t.buf); | |
502 | k_found:; | |
503 | ko = wantpriv ? kt->decops : kt->encops; | |
02dfbd5b MW |
504 | if (!ko->kf) { |
505 | kd = k->k; | |
506 | key_incref(kd); | |
78ec50fa | 507 | kp = 0; |
02dfbd5b MW |
508 | } else { |
509 | kd = xmalloc(ko->kdsz); | |
510 | kp = key_fetchinit(ko->kf, 0, kd); | |
511 | if ((e = key_fetch(kp, k)) != 0) { | |
512 | die(EXIT_FAILURE, "error fetching key `%s': %s", | |
513 | t.buf, key_strerror(e)); | |
514 | } | |
515 | } | |
5c3f75ec | 516 | kk = ko->init(k, kd); |
517 | kk->kp = kp; | |
518 | kk->ops = ko; | |
519 | kk->kd = kd; | |
520 | ||
521 | /* --- Set up the algorithms --- */ | |
522 | ||
523 | if (!halg) | |
524 | kk->h = &rmd160; | |
525 | else if ((kk->h = ghash_byname(halg)) == 0) { | |
526 | die(EXIT_FAILURE, "hash algorithm `%s' not found in key `%s'", | |
527 | halg, t.buf); | |
528 | } | |
529 | ||
530 | if (!calg) | |
531 | kk->c = &blowfish_cbc; | |
532 | else if ((kk->c = gcipher_byname(calg)) == 0) { | |
533 | die(EXIT_FAILURE, "encryption scheme `%s' not found in key `%s'", | |
534 | calg, t.buf); | |
535 | } | |
536 | ||
537 | dstr_reset(&d); | |
538 | if ((q = key_getattr(0, k, "kdf")) == 0) { | |
539 | dstr_putf(&d, "%s-mgf", kk->h->name); | |
540 | q = d.buf; | |
541 | } | |
542 | if ((kk->cx = gcipher_byname(q)) == 0) { | |
543 | die(EXIT_FAILURE, "encryption scheme (KDF) `%s' not found in key `%s'", | |
544 | q, t.buf); | |
545 | } | |
45c0fd36 | 546 | |
5c3f75ec | 547 | dstr_reset(&d); |
548 | if ((q = key_getattr(0, k, "mac")) == 0) { | |
549 | dstr_putf(&d, "%s-hmac", kk->h->name); | |
550 | q = d.buf; | |
551 | } | |
552 | if ((kk->m = gmac_byname(q)) == 0) { | |
553 | die(EXIT_FAILURE, | |
554 | "message authentication code `%s' not found in key `%s'", | |
555 | q, t.buf); | |
556 | } | |
557 | ||
558 | /* --- Tidy up --- */ | |
559 | ||
560 | dstr_destroy(&d); | |
561 | dstr_destroy(&t); | |
562 | return (kk); | |
563 | } | |
564 | ||
565 | /* --- @setupkem@ --- * | |
566 | * | |
567 | * Arguments: @kem *k@ = key-encapsulation thing | |
568 | * @dstr *d@ = key-encapsulation data | |
569 | * @gcipher **cx@ = key-expansion function (for IVs) | |
570 | * @gcipher **c@ = where to put initialized encryption scheme | |
571 | * @gmac **m@ = where to put initialized MAC | |
572 | * | |
573 | * Returns: Zero on success, nonzero on failure. | |
574 | * | |
575 | * Use: Initializes all the various symmetric things from a KEM. | |
576 | */ | |
577 | ||
578 | int setupkem(kem *k, dstr *d, gcipher **cx, gcipher **c, gmac **m) | |
579 | { | |
580 | octet *kd; | |
581 | size_t n, cn, mn; | |
582 | ghash *h; | |
c65df279 | 583 | int rc = -1; |
5c3f75ec | 584 | |
585 | h = GH_INIT(k->h); | |
586 | if (k->ops->doit(k, d, h)) | |
587 | goto done; | |
588 | n = keysz(GH_CLASS(h)->hashsz, k->cx->keysz); | |
589 | if (!n) | |
590 | goto done; | |
591 | kd = GH_DONE(h, 0); | |
592 | *cx = GC_INIT(k->cx, kd, n); | |
593 | ||
594 | cn = keysz(0, k->c->keysz); n = cn; | |
595 | mn = keysz(0, k->m->keysz); if (mn > n) n = mn; | |
596 | kd = xmalloc(n); | |
597 | GC_ENCRYPT(*cx, 0, kd, cn); | |
598 | *c = GC_INIT(k->c, kd, cn); | |
599 | GC_ENCRYPT(*cx, 0, kd, mn); | |
600 | *m = GM_KEY(k->m, kd, mn); | |
601 | xfree(kd); | |
602 | ||
603 | rc = 0; | |
604 | done: | |
605 | GH_DESTROY(h); | |
606 | return (rc); | |
607 | } | |
608 | ||
609 | /* --- @freekem@ --- * | |
610 | * | |
611 | * Arguments: @kem *k@ = key-encapsulation thing | |
612 | * | |
613 | * Returns: --- | |
614 | * | |
615 | * Use: Frees up a key-encapsulation thing. | |
616 | */ | |
617 | ||
618 | void freekem(kem *k) | |
619 | { | |
02dfbd5b MW |
620 | if (!k->ops->kf) |
621 | key_drop(k->kd); | |
622 | else { | |
623 | key_fetchdone(k->kp); | |
624 | xfree(k->kd); | |
625 | } | |
5c3f75ec | 626 | k->ops->destroy(k); |
627 | } | |
628 | ||
629 | /*----- That's all, folks -------------------------------------------------*/ |