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5b9f3d37 MW |
1 | /* -*-c-*- |
2 | * | |
3 | * Diffie--Hellman groups | |
4 | * | |
5 | * (c) 2017 Straylight/Edgeware | |
6 | */ | |
7 | ||
8 | /*----- Licensing notice --------------------------------------------------* | |
9 | * | |
10 | * This file is part of Trivial IP Encryption (TrIPE). | |
11 | * | |
11ad66c2 MW |
12 | * TrIPE is free software: you can redistribute it and/or modify it under |
13 | * the terms of the GNU General Public License as published by the Free | |
14 | * Software Foundation; either version 3 of the License, or (at your | |
15 | * option) any later version. | |
5b9f3d37 | 16 | * |
11ad66c2 MW |
17 | * TrIPE is distributed in the hope that it will be useful, but WITHOUT |
18 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
19 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
20 | * for more details. | |
5b9f3d37 MW |
21 | * |
22 | * You should have received a copy of the GNU General Public License | |
11ad66c2 | 23 | * along with TrIPE. If not, see <https://www.gnu.org/licenses/>. |
5b9f3d37 MW |
24 | */ |
25 | ||
26 | /*----- Header files ------------------------------------------------------*/ | |
27 | ||
28 | #include "tripe.h" | |
29 | ||
30 | /*----- Common utilities --------------------------------------------------*/ | |
31 | ||
32 | /* --- @KLOAD@ --- * | |
33 | * | |
34 | * Arguments: @pre@ = prefix for defined functions | |
35 | * @ty@, @TY@ = key type name (lower- and upper-case) | |
36 | * @setgroup@ = code to initialize @kd->g@ | |
37 | * @setpriv@ = code to initialize @kd->kpriv@ | |
38 | * @setpub@ = code to initialize @kd->kpub@ | |
39 | * | |
40 | * Use: Generates the body of one of the (rather tedious) key loading | |
41 | * functions. See the description of @KEYTYPES@ below for the | |
42 | * details. | |
43 | */ | |
44 | ||
45 | #define KLOAD_HALF(pre, ty, TY, which, WHICH, setgroup, setpriv, setpub) \ | |
46 | static int pre##_ld##which(key_file *kf, key *k, key_data *d, \ | |
47 | kdata *kd, dstr *t, dstr *e) \ | |
48 | { \ | |
49 | key_packstruct kps[TY##_##WHICH##FETCHSZ]; \ | |
50 | key_packdef *kp; \ | |
51 | ty##_##which p; \ | |
52 | int rc; \ | |
53 | \ | |
54 | /* --- Initialize things we've not set up yet --- */ \ | |
55 | \ | |
56 | kd->grp = 0; kd->k = 0; kd->K = 0; \ | |
57 | \ | |
58 | /* --- Unpack the key --- */ \ | |
59 | \ | |
60 | kp = key_fetchinit(ty##_##which##fetch, kps, &p); \ | |
61 | if ((rc = key_unpack(kp, d, t)) != 0) { \ | |
62 | a_format(e, "unpack-failed", "%s", key_strerror(rc), A_END); \ | |
63 | goto fail; \ | |
64 | } \ | |
65 | \ | |
66 | /* --- Extract the pieces of the key --- */ \ | |
67 | \ | |
68 | setgroup; \ | |
69 | setpriv; \ | |
70 | setpub; \ | |
71 | \ | |
72 | /* --- We win --- */ \ | |
73 | \ | |
74 | rc = 0; \ | |
75 | goto done; \ | |
76 | \ | |
77 | fail: \ | |
78 | if (kd->grp) { \ | |
79 | if (kd->K) pre##_freege(kd->grp, kd->K); \ | |
80 | if (kd->k) pre##_freesc(kd->grp, kd->k); \ | |
81 | pre##_freegrp(kd->grp); \ | |
82 | } \ | |
83 | rc = -1; \ | |
84 | \ | |
85 | done: \ | |
86 | key_fetchdone(kp); \ | |
87 | return (rc); \ | |
88 | } | |
89 | ||
90 | #define KLOAD(pre, ty, TY, setgroup, setpriv, setpub) \ | |
91 | static void pre##_freegrp(dhgrp *); \ | |
92 | static void pre##_freesc(const dhgrp *, dhsc *); \ | |
93 | static void pre##_freege(const dhgrp *, dhge *); \ | |
94 | KLOAD_HALF(pre, ty, TY, priv, PRIV, setgroup, setpriv, setpub) \ | |
95 | KLOAD_HALF(pre, ty, TY, pub, PUB, setgroup, { kd->k = 0; }, setpub) | |
96 | ||
07bdda1f MW |
97 | enum { DHSER_V0, DHSER_CONSTLEN }; |
98 | ||
99 | static int get_serialization(key_file *kf, key *k, dstr *e) | |
100 | { | |
101 | const char *p = key_getattr(kf, k, "serialization"); | |
102 | if (!p || strcmp(p, "v0") == 0) return (DHSER_V0); | |
103 | else if (strcmp(p, "constlen") == 0) return (DHSER_CONSTLEN); | |
104 | else { | |
105 | a_format(e, "unknown-serialization-format", "%s", p, A_END); | |
106 | return (-1); | |
107 | } | |
108 | } | |
109 | ||
5b9f3d37 MW |
110 | #ifndef NTRACE |
111 | static void setupstr(mptext_stringctx *sc) | |
112 | { sc->buf = (char *)buf_u; sc->lim = sc->buf + sizeof(buf_u); } | |
113 | ||
114 | static const char *donestr(mptext_stringctx *sc) | |
115 | { *sc->buf = 0; return ((const char *)buf_u); } | |
116 | ||
117 | static void addlitstr(const char *p, mptext_stringctx *sc) | |
118 | { mptext_stringops.put(p, strlen(p), sc); } | |
119 | ||
120 | static void addmpstr(mp *x, int radix, mptext_stringctx *sc) | |
121 | { | |
122 | char b[12]; | |
123 | ||
124 | if (radix == 16) addlitstr("0x", sc); | |
125 | else if (radix == 8) addlitstr("0", sc); | |
126 | else if (radix != 10) { sprintf(b, "%d#", radix); addlitstr(b, sc); } | |
127 | mp_write(x, radix, &mptext_stringops, sc); | |
128 | } | |
129 | ||
130 | static const char *mpstr(mp *x, int radix) | |
131 | { | |
132 | mptext_stringctx sc; | |
133 | ||
134 | setupstr(&sc); | |
135 | addmpstr(x, radix, &sc); | |
136 | return (donestr(&sc)); | |
137 | } | |
138 | #endif | |
139 | ||
140 | /*----- Schnorr groups ----------------------------------------------------*/ | |
141 | ||
142 | typedef struct intdh_grp { | |
143 | dhgrp _g; | |
144 | mpmont mm; | |
145 | mp *q, *G; | |
146 | size_t gesz; | |
07bdda1f | 147 | int ser; |
5b9f3d37 MW |
148 | } intdh_grp; |
149 | ||
150 | typedef struct intdh_sc { mp *x; } intdh_sc; | |
151 | typedef struct intdh_ge { mp *X; } intdh_ge; | |
152 | ||
07bdda1f MW |
153 | static dhgrp *intdh_mkgroup(key_file *kf, key *k, |
154 | const dh_param *dp, dstr *e) | |
5b9f3d37 | 155 | { |
07bdda1f MW |
156 | intdh_grp *g; |
157 | int ser; | |
158 | ||
159 | if ((ser = get_serialization(kf, k, e)) < 0) return (0); | |
160 | g = CREATE(intdh_grp); | |
161 | g->ser = ser; | |
5b9f3d37 MW |
162 | g->_g.scsz = mp_octets(dp->q); |
163 | g->gesz = mp_octets(dp->p); | |
164 | mpmont_create(&g->mm, dp->p); | |
165 | g->q = MP_COPY(dp->q); | |
166 | g->G = mpmont_mul(&g->mm, MP_NEW, dp->g, g->mm.r2); | |
167 | return (&g->_g); | |
168 | } | |
169 | ||
170 | static dhsc *intdh_mptosc(const dhgrp *gg, mp *z) | |
171 | { | |
172 | const intdh_grp *g = (const intdh_grp *)gg; | |
173 | intdh_sc *x = CREATE(intdh_sc); | |
174 | x->x = MP_NEW; mp_div(0, &x->x, z, g->q); | |
175 | return ((dhsc *)x); | |
176 | } | |
177 | ||
178 | static dhge *intdh_mptoge(const dhgrp *gg, mp *z) | |
179 | { | |
180 | const intdh_grp *g = (const intdh_grp *)gg; | |
181 | intdh_ge *Y = CREATE(intdh_ge); | |
182 | mp *t = MP_NEW; mp_div(0, &t, z, g->mm.m); | |
183 | Y->X = mpmont_mul(&g->mm, t, t, g->mm.r2); | |
184 | return ((dhge *)Y); | |
185 | } | |
186 | ||
187 | KLOAD(intdh, dh, DH, | |
07bdda1f | 188 | { if ((kd->grp = intdh_mkgroup(kf, k, &p.dp, e)) == 0) goto fail; }, |
5b9f3d37 MW |
189 | { kd->k = intdh_mptosc(kd->grp, p.x); }, |
190 | { kd->K = intdh_mptoge(kd->grp, p.y); }) | |
191 | ||
192 | static const char *intdh_checkgrp(const dhgrp *gg) | |
193 | { | |
194 | const intdh_grp *g = (const intdh_grp *)gg; | |
195 | mp *t = MP_NEW; | |
196 | ||
197 | if (!pgen_primep(g->mm.m, &rand_global)) return ("p is not prime"); | |
198 | if (!pgen_primep(g->q, &rand_global)) return ("q is not prime"); | |
199 | mp_div(0, &t, g->mm.m, g->q); | |
200 | if (!MP_EQ(t, MP_ONE)) return ("q is not a subgroup order"); | |
201 | t = mpmont_expr(&g->mm, t, g->G, g->q); | |
202 | if (!MP_EQ(t, g->mm.r)) return ("g not in the subgroup"); | |
203 | return (0); | |
204 | } | |
205 | ||
206 | static void intdh_grpinfo(const dhgrp *gg, admin *adm) | |
207 | { | |
208 | const intdh_grp *g = (const intdh_grp *)gg; | |
209 | a_info(adm, | |
210 | "kx-group=prime", | |
211 | "kx-group-order-bits=%lu", (unsigned long)mp_bits(g->q), | |
212 | "kx-group-elt-bits=%lu", (unsigned long)mp_bits(g->mm.m), | |
213 | A_END); | |
214 | } | |
215 | ||
216 | #ifndef NTRACE | |
217 | static void intdh_tracegrp(const dhgrp *gg) | |
218 | { | |
219 | const intdh_grp *g = (const intdh_grp *)gg; | |
220 | mp *t = MP_NEW; | |
221 | trace(T_CRYPTO, "crypto: group type `dh'"); | |
222 | trace(T_CRYPTO, "crypto: p = %s", mpstr(g->mm.m, 10)); | |
223 | trace(T_CRYPTO, "crypto: q = %s", mpstr(g->q, 10)); | |
224 | t = mpmont_reduce(&g->mm, t, g->G); | |
225 | trace(T_CRYPTO, "crypto: g = %s", mpstr(t, 10)); | |
226 | MP_DROP(t); | |
227 | } | |
228 | #endif | |
229 | ||
230 | static int intdh_samegrpp(const dhgrp *gg, const dhgrp *hh) | |
231 | { | |
232 | const intdh_grp *g = (const intdh_grp *)gg, *h = (const intdh_grp *)hh; | |
07bdda1f MW |
233 | return (MP_EQ(g->mm.m, h->mm.m) && |
234 | MP_EQ(g->q, h->q) && MP_EQ(g->G, h->G) && | |
235 | g->ser == h->ser); | |
5b9f3d37 MW |
236 | } |
237 | ||
238 | static void intdh_freegrp(dhgrp *gg) | |
239 | { | |
240 | intdh_grp *g = (intdh_grp *)gg; | |
241 | mpmont_destroy(&g->mm); MP_DROP(g->q); MP_DROP(g->G); | |
242 | DESTROY(g); | |
243 | } | |
244 | ||
245 | static dhsc *intdh_ldsc(const dhgrp *gg, const void *p, size_t sz) | |
246 | { const intdh_grp *g = (const intdh_grp *)gg; | |
247 | intdh_sc *x = CREATE(intdh_sc); | |
248 | mp *t = mp_loadb(MP_NEW, p, sz); | |
249 | mp_div(0, &t, t, g->q); x->x = t; | |
250 | return ((dhsc *)x); | |
251 | } | |
252 | ||
253 | static int intdh_stsc(const dhgrp *gg, void *p, size_t sz, const dhsc *xx) | |
254 | { | |
255 | const intdh_sc *x = (const intdh_sc *)xx; | |
256 | mp_storeb(x->x, p, sz); | |
257 | return (0); | |
258 | } | |
259 | ||
260 | static dhsc *intdh_randsc(const dhgrp *gg) | |
261 | { | |
262 | const intdh_grp *g = (const intdh_grp *)gg; | |
263 | intdh_sc *x = CREATE(intdh_sc); | |
264 | x->x = mprand_range(MP_NEW, g->q, &rand_global, 0); | |
265 | return ((dhsc *)x); | |
266 | } | |
267 | ||
268 | #ifndef NTRACE | |
269 | static const char *intdh_scstr(const dhgrp *gg, const dhsc *xx) | |
270 | { const intdh_sc *x = (const intdh_sc *)xx; return (mpstr(x->x, 10)); } | |
271 | #endif | |
272 | ||
273 | static void intdh_freesc(const dhgrp *gg, dhsc *xx) | |
274 | { | |
275 | intdh_sc *x = (intdh_sc *)xx; | |
276 | MP_DROP(x->x); DESTROY(x); | |
277 | } | |
278 | ||
279 | static dhge *intdh_ldge(const dhgrp *gg, buf *b, int fmt) | |
280 | { | |
281 | const intdh_grp *g = (const intdh_grp *)gg; | |
282 | intdh_ge *Y; | |
283 | mp *t; | |
284 | const octet *p; | |
285 | ||
286 | switch (fmt) { | |
07bdda1f MW |
287 | case DHFMT_HASH: if (g->ser == DHSER_CONSTLEN) goto std; |
288 | case DHFMT_VAR: | |
5b9f3d37 MW |
289 | if ((t = buf_getmp(b)) == 0) return (0); |
290 | break; | |
07bdda1f | 291 | case DHFMT_STD: std: |
5b9f3d37 MW |
292 | if ((p = buf_get(b, g->gesz)) == 0) return (0); |
293 | t = mp_loadb(MP_NEW, p, g->gesz); | |
294 | break; | |
295 | default: | |
296 | abort(); | |
297 | } | |
298 | Y = CREATE(intdh_ge); | |
299 | mp_div(0, &t, t, g->mm.m); | |
300 | Y->X = mpmont_mul(&g->mm, t, t, g->mm.r2); | |
301 | return ((dhge *)Y); | |
302 | } | |
303 | ||
304 | static int intdh_stge(const dhgrp *gg, buf *b, const dhge *YY, int fmt) | |
305 | { | |
306 | const intdh_grp *g = (const intdh_grp *)gg; | |
307 | const intdh_ge *Y = (const intdh_ge *)YY; | |
308 | octet *p; | |
309 | mp *t; | |
310 | int rc; | |
311 | ||
312 | t = mpmont_reduce(&g->mm, MP_NEW, Y->X); | |
313 | switch (fmt) { | |
07bdda1f MW |
314 | case DHFMT_HASH: if (g->ser == DHSER_CONSTLEN) goto std; |
315 | case DHFMT_VAR: | |
5b9f3d37 MW |
316 | rc = buf_putmp(b, t); |
317 | break; | |
07bdda1f | 318 | case DHFMT_STD: std: |
5b9f3d37 MW |
319 | if ((p = buf_get(b, g->gesz)) == 0) |
320 | rc = -1; | |
321 | else { | |
322 | mp_storeb(t, p, g->gesz); | |
323 | rc = 0; | |
324 | } | |
325 | break; | |
326 | default: | |
327 | abort(); | |
328 | } | |
329 | MP_DROP(t); | |
330 | return (rc); | |
331 | } | |
332 | ||
333 | static int intdh_checkge(const dhgrp *gg, const dhge *YY) | |
334 | { | |
335 | const intdh_grp *g = (const intdh_grp *)gg; | |
336 | const intdh_ge *Y = (const intdh_ge *)YY; | |
337 | mp *T; | |
338 | int rc = 0; | |
339 | ||
340 | if (MP_EQ(Y->X, g->mm.r)) rc = -1; | |
341 | T = mpmont_expr(&g->mm, MP_NEW, Y->X, g->q); | |
342 | if (!MP_EQ(T, g->mm.r)) rc = -1; | |
343 | MP_DROP(T); | |
344 | return (rc); | |
345 | } | |
346 | ||
347 | static int intdh_eq(const dhgrp *gg, const dhge *YY, const dhge *ZZ) | |
348 | { | |
349 | const intdh_ge *Y = (const intdh_ge *)YY, *Z = (const intdh_ge *)ZZ; | |
350 | return (MP_EQ(Y->X, Z->X)); | |
351 | } | |
352 | ||
353 | static dhge *intdh_mul(const dhgrp *gg, const dhsc *xx, const dhge *YY) | |
354 | { | |
355 | const intdh_grp *g = (const intdh_grp *)gg; | |
356 | const intdh_sc *x = (const intdh_sc *)xx; | |
357 | const intdh_ge *Y = (const intdh_ge *)YY; | |
358 | intdh_ge *Z = CREATE(intdh_ge); | |
359 | ||
360 | Z->X = mpmont_expr(&g->mm, MP_NEW, Y ? Y->X : g->G, x->x); | |
361 | return ((dhge *)Z); | |
362 | } | |
363 | ||
364 | #ifndef NTRACE | |
365 | static const char *intdh_gestr(const dhgrp *gg, const dhge *YY) | |
366 | { | |
367 | const intdh_grp *g = (const intdh_grp *)gg; | |
368 | const intdh_ge *Y = (const intdh_ge *)YY; | |
369 | mp *t = mpmont_reduce(&g->mm, MP_NEW, Y->X); | |
370 | const char *p = mpstr(t, 10); | |
371 | MP_DROP(t); | |
372 | return (p); | |
373 | } | |
374 | #endif | |
375 | ||
376 | static void intdh_freege(const dhgrp *gg, dhge *YY) | |
377 | { intdh_ge *Y = (intdh_ge *)YY; MP_DROP(Y->X); DESTROY(Y); } | |
378 | ||
379 | /*----- Elliptic curve groups ---------------------------------------------*/ | |
380 | ||
381 | typedef struct ecdh_grp { | |
382 | dhgrp _g; | |
383 | ec_info ei; | |
384 | ec P; | |
07bdda1f | 385 | int ser; |
5b9f3d37 MW |
386 | } ecdh_grp; |
387 | ||
388 | typedef struct ecdh_sc { mp *x; } ecdh_sc; | |
389 | typedef struct ecdh_ge { ec Q; } ecdh_ge; | |
390 | ||
07bdda1f | 391 | static dhgrp *ecdh_mkgroup(key_file *kf, key *k, const char *cstr, dstr *e) |
5b9f3d37 MW |
392 | { |
393 | ecdh_grp *g; | |
394 | ec_info ei; | |
07bdda1f | 395 | int ser; |
5b9f3d37 MW |
396 | const char *err; |
397 | ||
07bdda1f | 398 | if ((ser = get_serialization(kf, k, e)) < 0) return (0); |
5b9f3d37 MW |
399 | if ((err = ec_getinfo(&ei, cstr)) != 0) { |
400 | a_format(e, "decode-failed", "%s", err, A_END); | |
401 | return (0); | |
402 | } | |
403 | g = CREATE(ecdh_grp); | |
07bdda1f | 404 | g->ser = ser; |
5b9f3d37 MW |
405 | g->ei = ei; |
406 | EC_CREATE(&g->P); EC_IN(g->ei.c, &g->P, &g->ei.g); | |
407 | g->_g.scsz = mp_octets(g->ei.r); | |
408 | return (&g->_g); | |
409 | } | |
410 | ||
411 | static dhsc *ecdh_mptosc(const dhgrp *gg, mp *z) | |
412 | { | |
413 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
414 | ecdh_sc *x = CREATE(ecdh_sc); | |
415 | x->x = MP_NEW; mp_div(0, &x->x, z, g->ei.r); | |
416 | return ((dhsc *)x); | |
417 | } | |
418 | ||
419 | static dhge *ecdh_ectoge(const dhgrp *gg, ec *Q) | |
420 | { | |
421 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
422 | ecdh_ge *Y = CREATE(ecdh_ge); EC_CREATE(&Y->Q); | |
423 | EC_IN(g->ei.c, &Y->Q, Q); | |
424 | if (EC_CHECK(g->ei.c, &Y->Q)) | |
425 | { EC_DESTROY(&Y->Q); DESTROY(Y); return (0); } | |
426 | return ((dhge *)Y); | |
427 | } | |
428 | ||
429 | KLOAD(ecdh, ec, EC, | |
07bdda1f | 430 | { if ((kd->grp = ecdh_mkgroup(kf, k, p.cstr, e)) == 0) goto fail; }, |
5b9f3d37 MW |
431 | { kd->k = ecdh_mptosc(kd->grp, p.x); }, |
432 | { if ((kd->K = ecdh_ectoge(kd->grp, &p.p)) == 0) { | |
433 | a_format(e, "bad-public-vector", A_END); | |
434 | goto fail; | |
435 | } | |
436 | }) | |
437 | ||
438 | static const char *ecdh_checkgrp(const dhgrp *gg) | |
439 | { | |
440 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
441 | return (ec_checkinfo(&g->ei, &rand_global)); | |
442 | } | |
443 | ||
444 | static void ecdh_grpinfo(const dhgrp *gg, admin *adm) | |
445 | { | |
446 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
447 | a_info(adm, | |
448 | "kx-group=ec", | |
449 | "kx-group-order-bits=%lu", (unsigned long)mp_bits(g->ei.r), | |
450 | "kx-group-elt-bits=%lu", (unsigned long)2*g->ei.c->f->nbits, | |
451 | A_END); | |
452 | } | |
453 | ||
454 | #ifndef NTRACE | |
455 | static void addfestr(field *f, mp *x, mptext_stringctx *sc) | |
456 | { addmpstr(x, F_TYPE(f) == FTY_PRIME ? 10 : 16, sc); } | |
457 | ||
458 | static void addintfestr(field *f, mp *x, mptext_stringctx *sc) | |
459 | { mp *t = F_OUT(f, MP_NEW, x); addfestr(f, x, sc); MP_DROP(t); } | |
460 | ||
461 | static const char *intfestr(field *f, mp *x) | |
462 | { | |
463 | mptext_stringctx sc; | |
464 | setupstr(&sc); | |
465 | addintfestr(f, x, &sc); | |
466 | return (donestr(&sc)); | |
467 | } | |
468 | ||
469 | static void ecdh_tracegrp(const dhgrp *gg) | |
470 | { | |
471 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
472 | const ec_curve *c = g->ei.c; | |
473 | field *f = c->f; | |
474 | ||
475 | trace(T_CRYPTO, "crypto: group type `ec'"); | |
476 | switch (F_TYPE(f)) { | |
477 | case FTY_PRIME: | |
478 | trace(T_CRYPTO, "crypto: prime field `%s'", F_NAME(f)); | |
479 | trace(T_CRYPTO, "crypto: p = %s", mpstr(f->q, 10)); | |
480 | break; | |
481 | case FTY_BINARY: | |
482 | trace(T_CRYPTO, "crypto: binary field `%s'", F_NAME(f)); | |
483 | trace(T_CRYPTO, "crypto: degree = %lu", f->nbits - 1); | |
484 | break; | |
485 | default: | |
486 | trace(T_CRYPTO, "crypto: unknown field type! `%s'", F_NAME(f)); | |
487 | break; | |
488 | } | |
489 | trace(T_CRYPTO, "crypto: curve type `%s'", EC_NAME(c)); | |
490 | trace(T_CRYPTO, "crypto: curve a = %s", intfestr(f, c->a)); | |
491 | trace(T_CRYPTO, "crypto: curve b = %s", intfestr(f, c->b)); | |
492 | trace(T_CRYPTO, "crypto: n = %s", mpstr(g->ei.r, 10)); | |
493 | trace(T_CRYPTO, "crypto: h = %s", mpstr(g->ei.h, 10)); | |
494 | } | |
495 | #endif | |
496 | ||
497 | static int ecdh_samegrpp(const dhgrp *gg, const dhgrp *hh) | |
498 | { | |
499 | const ecdh_grp *g = (const ecdh_grp *)gg, *h = (const ecdh_grp *)hh; | |
07bdda1f MW |
500 | return (ec_sameinfop(&g->ei, &h->ei) && |
501 | g->ser == h->ser); | |
5b9f3d37 MW |
502 | } |
503 | ||
504 | static void ecdh_freegrp(dhgrp *gg) | |
505 | { | |
506 | ecdh_grp *g = (ecdh_grp *)gg; | |
507 | EC_DESTROY(&g->P); ec_freeinfo(&g->ei); | |
508 | DESTROY(g); | |
509 | } | |
510 | ||
511 | static dhsc *ecdh_ldsc(const dhgrp *gg, const void *p, size_t sz) | |
512 | { | |
513 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
514 | ecdh_sc *x = CREATE(ecdh_sc); | |
515 | mp *t = mp_loadb(MP_NEW, p, sz); | |
516 | mp_div(0, &t, t, g->ei.r); x->x = t; | |
517 | return ((dhsc *)x); | |
518 | } | |
519 | ||
520 | static int ecdh_stsc(const dhgrp *gg, void *p, size_t sz, const dhsc *xx) | |
521 | { | |
522 | const ecdh_sc *x = (const ecdh_sc *)xx; | |
523 | mp_storeb(x->x, p, sz); | |
524 | return (0); | |
525 | } | |
526 | ||
527 | static dhsc *ecdh_randsc(const dhgrp *gg) | |
528 | { | |
529 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
530 | ecdh_sc *x = CREATE(ecdh_sc); | |
531 | x->x = mprand_range(MP_NEW, g->ei.r, &rand_global, 0); | |
532 | return ((dhsc *)x); | |
533 | } | |
534 | ||
535 | #ifndef NTRACE | |
536 | static const char *ecdh_scstr(const dhgrp *gg, const dhsc *xx) | |
537 | { | |
538 | const ecdh_sc *x = (const ecdh_sc *)xx; | |
539 | return (mpstr(x->x, 10)); | |
540 | } | |
541 | #endif | |
542 | ||
543 | static void ecdh_freesc(const dhgrp *gg, dhsc *xx) | |
544 | { ecdh_sc *x = (ecdh_sc *)xx; MP_DROP(x->x); DESTROY(x); } | |
545 | ||
546 | static dhge *ecdh_ldge(const dhgrp *gg, buf *b, int fmt) | |
547 | { | |
548 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
549 | ecdh_ge *Y; | |
550 | ec T = EC_INIT; | |
551 | ||
552 | switch (fmt) { | |
07bdda1f MW |
553 | case DHFMT_HASH: if (g->ser == DHSER_CONSTLEN) goto std; |
554 | case DHFMT_VAR: if (buf_getec(b, &T)) return (0); break; | |
555 | case DHFMT_STD: std: if (ec_getraw(g->ei.c, b, &T)) return (0); break; | |
5b9f3d37 MW |
556 | default: |
557 | abort(); | |
558 | } | |
559 | EC_IN(g->ei.c, &T, &T); | |
560 | Y = CREATE(ecdh_ge); Y->Q = T; | |
561 | return ((dhge *)Y); | |
562 | } | |
563 | ||
564 | static int ecdh_stge(const dhgrp *gg, buf *b, const dhge *YY, int fmt) | |
565 | { | |
566 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
567 | const ecdh_ge *Y = (const ecdh_ge *)YY; | |
568 | ec T = EC_INIT; | |
569 | int rc; | |
570 | ||
571 | EC_OUT(g->ei.c, &T, &Y->Q); | |
572 | switch (fmt) { | |
07bdda1f MW |
573 | case DHFMT_HASH: if (g->ser == DHSER_CONSTLEN) goto std; |
574 | case DHFMT_VAR: rc = buf_putec(b, &T); break; | |
575 | case DHFMT_STD: std: rc = ec_putraw(g->ei.c, b, &T); break; | |
5b9f3d37 MW |
576 | default: abort(); |
577 | } | |
578 | EC_DESTROY(&T); | |
579 | return (rc); | |
580 | } | |
581 | ||
582 | static int ecdh_checkge(const dhgrp *gg, const dhge *YY) | |
583 | { | |
584 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
585 | const ecdh_ge *Y = (const ecdh_ge *)YY; | |
586 | ec T = EC_INIT; | |
587 | int rc = 0; | |
588 | ||
589 | if (EC_ATINF(&Y->Q)) rc = -1; | |
590 | ec_imul(g->ei.c, &T, &Y->Q, g->ei.r); | |
591 | if (!EC_ATINF(&T)) rc = -1; | |
592 | EC_DESTROY(&T); | |
593 | return (rc); | |
594 | } | |
595 | ||
596 | static int ecdh_eq(const dhgrp *gg, const dhge *YY, const dhge *ZZ) | |
597 | { | |
598 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
599 | const ecdh_ge *Y = (const ecdh_ge *)YY, *Z = (const ecdh_ge *)ZZ; | |
600 | ec T = EC_INIT, U = EC_INIT; int rc; | |
601 | EC_FIX(g->ei.c, &T, &Y->Q); EC_FIX(g->ei.c, &U, &Z->Q); | |
602 | rc = EC_EQ(&T, &U); | |
603 | EC_DESTROY(&T); EC_DESTROY(&U); | |
604 | return (rc); | |
605 | } | |
606 | ||
607 | static dhge *ecdh_mul(const dhgrp *gg, const dhsc *xx, const dhge *YY) | |
608 | { | |
609 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
610 | const ecdh_sc *x = (const ecdh_sc *)xx; | |
611 | const ecdh_ge *Y = (const ecdh_ge *)YY; | |
612 | ecdh_ge *Z = CREATE(ecdh_ge); EC_CREATE(&Z->Q); | |
613 | ||
614 | ec_imul(g->ei.c, &Z->Q, Y ? &Y->Q : &g->P, x->x); | |
615 | return ((dhge *)Z); | |
616 | } | |
617 | ||
618 | #ifndef NTRACE | |
619 | static const char *ecdh_gestr(const dhgrp *gg, const dhge *YY) | |
620 | { | |
621 | const ecdh_grp *g = (const ecdh_grp *)gg; | |
622 | const ecdh_ge *Y = (const ecdh_ge *)YY; | |
623 | ec T = EC_INIT; | |
624 | field *f = g->ei.c->f; | |
625 | mptext_stringctx sc; | |
626 | ||
627 | if (EC_ATINF(&Y->Q)) return ("inf"); | |
628 | setupstr(&sc); | |
629 | EC_OUT(g->ei.c, &T, &Y->Q); | |
630 | addfestr(f, T.x, &sc); | |
631 | addlitstr(", ", &sc); | |
632 | addfestr(f, T.y, &sc); | |
633 | EC_DESTROY(&T); | |
634 | return (donestr(&sc)); | |
635 | } | |
636 | #endif | |
637 | ||
638 | static void ecdh_freege(const dhgrp *gg, dhge *YY) | |
639 | { ecdh_ge *Y = (ecdh_ge *)YY; EC_DESTROY(&Y->Q); DESTROY(Y); } | |
640 | ||
26936c83 MW |
641 | /*----- The X25519 and similar groups -------------------------------------*/ |
642 | ||
643 | #define XDHS(_) \ | |
644 | _(x25519, X25519, "curve25519", 252, 255) \ | |
645 | _(x448, X448, "ed448-goldilocks", 446, 448) | |
646 | ||
647 | #ifdef NTRACE | |
648 | # define XDHTRACE(xdh, XDH, gname) | |
649 | #else | |
650 | ||
651 | static const char *binstr(const octet *p, size_t sz) | |
652 | { | |
653 | char *q; | |
654 | ||
655 | for (q = (char *)buf_u; sz--; p++, q += 2) sprintf(q, "%02x", *p); | |
656 | return ((const char *)buf_u); | |
657 | } | |
658 | ||
659 | # define XDHTRACE(xdh, XDH, gname) \ | |
660 | static void xdh##_tracegrp(const dhgrp *g) \ | |
661 | { trace(T_CRYPTO, "crypto: group type `" gname "'"); } \ | |
662 | \ | |
663 | static const char *xdh##_scstr(const dhgrp *g, const dhsc *xx) \ | |
664 | { \ | |
665 | const xdh##_sc *x = (const xdh##_sc *)xx; \ | |
666 | return (binstr(x->x, XDH##_KEYSZ)); \ | |
667 | } \ | |
668 | \ | |
669 | static const char *xdh##_gestr(const dhgrp *g, const dhge *YY) \ | |
670 | { \ | |
671 | const xdh##_ge *Y = (const xdh##_ge *)YY; \ | |
672 | return (binstr(Y->X, XDH##_PUBSZ)); \ | |
673 | } | |
674 | #endif | |
675 | ||
676 | #define XDHDEF(xdh, XDH, gname, groupbits, fieldbits) \ | |
677 | \ | |
678 | typedef struct xdh##_sc { octet x[XDH##_KEYSZ]; } xdh##_sc; \ | |
679 | typedef struct xdh##_ge { octet X[XDH##_PUBSZ]; } xdh##_ge; \ | |
680 | \ | |
681 | XDHTRACE(xdh, XDH, gname) \ | |
682 | \ | |
683 | static dhsc *xdh##_bintosc(const key_bin *b) \ | |
684 | { \ | |
685 | xdh##_sc *x; \ | |
686 | \ | |
687 | if (b->sz != XDH##_KEYSZ) return (0); \ | |
688 | x = CREATE(xdh##_sc); \ | |
689 | memcpy(x->x, b->k, XDH##_KEYSZ); \ | |
690 | return ((dhsc *)x); \ | |
691 | } \ | |
692 | \ | |
693 | static dhge *xdh##_bintoge(const key_bin *b) \ | |
694 | { \ | |
695 | xdh##_ge *Y; \ | |
696 | \ | |
697 | if (b->sz != XDH##_PUBSZ) return (0); \ | |
698 | Y = CREATE(xdh##_ge); \ | |
699 | memcpy(Y->X, b->k, XDH##_PUBSZ); \ | |
700 | return ((dhge *)Y); \ | |
701 | } \ | |
702 | \ | |
703 | KLOAD(xdh, xdh, XDH, \ | |
9dd1db76 MW |
704 | { kd->grp = CREATE(dhgrp); \ |
705 | kd->grp->scsz = XDH##_KEYSZ; \ | |
706 | }, \ | |
26936c83 MW |
707 | { if ((kd->k = xdh##_bintosc(&p.priv)) == 0) { \ |
708 | a_format(e, "bad-private-key", A_END); \ | |
709 | goto fail; \ | |
710 | } \ | |
711 | }, \ | |
712 | { if ((kd->K = xdh##_bintoge(&p.pub)) == 0) { \ | |
713 | a_format(e, "bad-public-vector", A_END); \ | |
714 | goto fail; \ | |
715 | } \ | |
716 | }) \ | |
717 | \ | |
718 | static const char *xdh##_checkgrp(const dhgrp *g) \ | |
719 | { return (0); } \ | |
720 | \ | |
721 | static void xdh##_grpinfo(const dhgrp *g, admin *adm) \ | |
722 | { \ | |
723 | a_info(adm, \ | |
724 | "kx-group=" gname, \ | |
725 | "kx-group-order-bits=%d", (groupbits), \ | |
726 | "kx-group-elt-bits=%d", (fieldbits), \ | |
727 | A_END); \ | |
728 | } \ | |
729 | \ | |
730 | static int xdh##_samegrpp(const dhgrp *g, const dhgrp *hh) \ | |
731 | { return (1); } \ | |
732 | \ | |
733 | static void xdh##_freegrp(dhgrp *g) \ | |
734 | { DESTROY(g); } \ | |
735 | \ | |
736 | static dhsc *xdh##_ldsc(const dhgrp *g, const void *p, size_t sz) \ | |
737 | { \ | |
738 | xdh##_sc *x; \ | |
739 | if (sz != XDH##_KEYSZ) return (0); \ | |
740 | x = CREATE(xdh##_sc); \ | |
741 | memcpy(x->x, p, XDH##_KEYSZ); \ | |
742 | return ((dhsc *)x); \ | |
743 | } \ | |
744 | \ | |
745 | static int xdh##_stsc(const dhgrp *g, void *p, size_t sz, \ | |
746 | const dhsc *xx) \ | |
747 | { \ | |
748 | const xdh##_sc *x = (const xdh##_sc *)xx; \ | |
749 | if (sz != XDH##_KEYSZ) return (-1); \ | |
750 | memcpy(p, x->x, XDH##_KEYSZ); \ | |
751 | return (0); \ | |
752 | } \ | |
753 | \ | |
754 | static dhsc *xdh##_randsc(const dhgrp *g) \ | |
755 | { \ | |
756 | xdh##_sc *x = CREATE(xdh##_sc); \ | |
757 | rand_get(RAND_GLOBAL, x->x, XDH##_KEYSZ); \ | |
758 | return ((dhsc *)x); \ | |
759 | } \ | |
760 | \ | |
761 | static void xdh##_freesc(const dhgrp *g, dhsc *xx) \ | |
762 | { xdh##_sc *x = (xdh##_sc *)xx; DESTROY(x); } \ | |
763 | \ | |
764 | static dhge *xdh##_ldge(const dhgrp *g, buf *b, int fmt) \ | |
765 | { \ | |
766 | xdh##_ge *Y; \ | |
767 | const octet *p; \ | |
768 | \ | |
769 | if ((p = buf_get(b, XDH##_PUBSZ)) == 0) return (0); \ | |
770 | Y = CREATE(xdh##_ge); memcpy(Y->X, p, XDH##_PUBSZ); \ | |
771 | return ((dhge *)Y); \ | |
772 | } \ | |
773 | \ | |
774 | static int xdh##_stge(const dhgrp *g, buf *b, \ | |
775 | const dhge *YY, int fmt) \ | |
776 | { \ | |
777 | const xdh##_ge *Y = (const xdh##_ge *)YY; \ | |
778 | return (buf_put(b, Y->X, XDH##_PUBSZ)); \ | |
779 | } \ | |
780 | \ | |
781 | static int xdh##_checkge(const dhgrp *g, const dhge *YY) \ | |
782 | { return (0); } \ | |
783 | \ | |
784 | static int xdh##_eq(const dhgrp *g, const dhge *YY, const dhge *ZZ) \ | |
785 | { \ | |
786 | const xdh##_ge \ | |
787 | *Y = (const xdh##_ge *)YY, *Z = (const xdh##_ge *)ZZ; \ | |
788 | return (ct_memeq(Y->X, Z->X, XDH##_PUBSZ)); \ | |
789 | } \ | |
790 | \ | |
791 | static dhge *xdh##_mul(const dhgrp *g, \ | |
792 | const dhsc *xx, const dhge *YY) \ | |
793 | { \ | |
794 | const xdh##_sc *x = (const xdh##_sc *)xx; \ | |
795 | const xdh##_ge *Y = (const xdh##_ge *)YY; \ | |
796 | xdh##_ge *Z = CREATE(xdh##_ge); \ | |
797 | \ | |
798 | xdh(Z->X, x->x, Y ? Y->X : xdh##_base); \ | |
799 | return ((dhge *)Z); \ | |
800 | } \ | |
801 | \ | |
802 | static void xdh##_freege(const dhgrp *g, dhge *YY) \ | |
803 | { xdh##_ge *Y = (xdh##_ge *)YY; DESTROY(Y); } | |
804 | ||
805 | XDHS(XDHDEF) | |
806 | ||
807 | #undef XDHDEF | |
808 | ||
5b9f3d37 MW |
809 | /*----- Diffie--Hellman group table ---------------------------------------*/ |
810 | ||
811 | const dhops dhtab[] = { | |
812 | ||
813 | #define COMMA , | |
814 | ||
815 | #define DH(name, pre) \ | |
816 | { name, pre##_ldpriv, pre##_ldpub, pre##_checkgrp, \ | |
817 | pre##_grpinfo, T( pre##_tracegrp COMMA ) pre##_samegrpp, \ | |
818 | pre##_freegrp, \ | |
819 | pre##_ldsc, pre##_stsc, pre##_randsc, T( pre##_scstr COMMA ) \ | |
820 | pre##_freesc, \ | |
821 | pre##_ldge, pre##_stge, pre##_checkge, pre##_eq, pre##_mul, \ | |
822 | T( pre##_gestr COMMA ) pre##_freege }, \ | |
823 | ||
824 | DH("dh", intdh) | |
825 | DH("ec", ecdh) | |
826 | ||
26936c83 MW |
827 | #define XDHDH(xdh, XDH, gname, groupbits, fieldbits) DH(#xdh, xdh) |
828 | XDHS(XDHDH) | |
829 | #undef XDHDH | |
830 | ||
5b9f3d37 MW |
831 | #undef DH |
832 | ||
833 | { 0 } | |
834 | }; | |
835 | ||
836 | /*----- That's all, folks -------------------------------------------------*/ |