b0ab12e6 |
1 | /* -*-c-*- |
2 | * |
b0ab12e6 |
3 | * Elliptic curve definitions |
4 | * |
5 | * (c) 2001 Straylight/Edgeware |
6 | */ |
7 | |
45c0fd36 |
8 | /*----- Licensing notice --------------------------------------------------* |
b0ab12e6 |
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. |
45c0fd36 |
16 | * |
b0ab12e6 |
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. |
45c0fd36 |
21 | * |
b0ab12e6 |
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 | |
b0ab12e6 |
28 | #ifndef CATACOMB_EC_H |
29 | #define CATACOMB_EC_H |
30 | |
31 | #ifdef __cplusplus |
32 | extern "C" { |
33 | #endif |
34 | |
35 | /*----- Header files ------------------------------------------------------*/ |
36 | |
432c4e18 |
37 | #ifndef CATACOMB_FIELD_H |
38 | # include "field.h" |
39 | #endif |
40 | |
41 | #ifndef CATACOMB_MP_H |
42 | # include "mp.h" |
43 | #endif |
44 | |
45 | #ifndef CATACOMB_QDPARSE_H |
46 | # include "qdparse.h" |
47 | #endif |
b0ab12e6 |
48 | |
49 | /*----- Data structures ---------------------------------------------------*/ |
50 | |
b085fd91 |
51 | /* --- An elliptic curve representation --- */ |
52 | |
b0ab12e6 |
53 | typedef struct ec_curve { |
54 | const struct ec_ops *ops; /* Curve operations */ |
55 | field *f; /* Underlying field structure */ |
432c4e18 |
56 | mp *a, *b; /* Standard params (internal form) */ |
b0ab12e6 |
57 | } ec_curve; |
58 | |
b085fd91 |
59 | /* --- An elliptic curve point --- */ |
60 | |
b0ab12e6 |
61 | typedef struct ec { |
62 | mp *x, *y; /* Point coordinates */ |
63 | mp *z; /* Common denominator (or null) */ |
64 | } ec; |
65 | |
b085fd91 |
66 | /* --- A factor for simultaneous multiplication --- */ |
67 | |
68 | typedef struct ec_mulfactor { |
69 | ec base; /* The point */ |
41cb1beb |
70 | mp *exp; /* The exponent */ |
b085fd91 |
71 | } ec_mulfactor; |
72 | |
8823192f |
73 | /* --- Elliptic curve operations --- * |
74 | * |
75 | * All operations (apart from @destroy@ and @in@) are guaranteed to be |
391faf42 |
76 | * performed on internal representations of points. |
77 | * |
78 | * (Historical note. We used to guarantee that the second to @add@ and @mul@ |
79 | * was the output of @in@ or @fix@, but this canonification turned out to |
80 | * make the precomputation in @ec_exp@ too slow. Projective implementations |
81 | * must therefore cope with a pair of arbitrary points.) |
8823192f |
82 | */ |
b085fd91 |
83 | |
b0ab12e6 |
84 | typedef struct ec_ops { |
f94b972d |
85 | const char *name; |
b0ab12e6 |
86 | void (*destroy)(ec_curve */*c*/); |
34e4f738 |
87 | int (*samep)(ec_curve */*c*/, ec_curve */*d*/); |
41a324a7 |
88 | ec *(*in)(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
89 | ec *(*out)(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
8823192f |
90 | ec *(*fix)(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
41a324a7 |
91 | ec *(*find)(ec_curve */*c*/, ec */*d*/, mp */*x*/); |
b085fd91 |
92 | ec *(*neg)(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
41a324a7 |
93 | ec *(*add)(ec_curve */*c*/, ec */*d*/, const ec */*p*/, const ec */*q*/); |
b085fd91 |
94 | ec *(*sub)(ec_curve */*c*/, ec */*d*/, const ec */*p*/, const ec */*q*/); |
41a324a7 |
95 | ec *(*dbl)(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
8823192f |
96 | int (*check)(ec_curve */*c*/, const ec */*p*/); |
b0ab12e6 |
97 | } ec_ops; |
98 | |
f94b972d |
99 | #define EC_NAME(c) (c)->ops->name |
100 | |
34e4f738 |
101 | #define EC_SAMEP(c, d) (c)->ops->samep((c), (d)) |
41a324a7 |
102 | #define EC_IN(c, d, p) (c)->ops->in((c), (d), (p)) |
dbfee00a |
103 | #define EC_OUT(c, d, p) (c)->ops->out((c), (d), (p)) |
8823192f |
104 | #define EC_FIX(c, d, p) (c)->ops->fix((c), (d), (p)) |
41a324a7 |
105 | |
b0ab12e6 |
106 | #define EC_FIND(c, d, x) (c)->ops->find((c), (d), (x)) |
b085fd91 |
107 | #define EC_NEG(c, d, x) (c)->ops->neg((c), (d), (x)) |
b0ab12e6 |
108 | #define EC_ADD(c, d, p, q) (c)->ops->add((c), (d), (p), (q)) |
b085fd91 |
109 | #define EC_SUB(c, d, p, q) (c)->ops->sub((c), (d), (p), (q)) |
b0ab12e6 |
110 | #define EC_DBL(c, d, p) (c)->ops->dbl((c), (d), (p)) |
8823192f |
111 | #define EC_CHECK(c, p) (c)->ops->check((c), (p)) |
b0ab12e6 |
112 | |
432c4e18 |
113 | /* --- Elliptic curve parameters --- */ |
114 | |
115 | typedef struct ec_info { |
116 | ec_curve *c; /* The actual curve */ |
117 | ec g; /* The common point */ |
118 | mp *r; /* Order of %$g$% */ |
119 | mp *h; /* Cofactor %$h = \#E/r$% */ |
120 | } ec_info; |
121 | |
b0ab12e6 |
122 | /*----- Simple memory management things -----------------------------------*/ |
123 | |
124 | /* --- @ec_create@ --- * |
125 | * |
126 | * Arguments: @ec *p@ = pointer to an elliptic-curve point |
127 | * |
41a324a7 |
128 | * Returns: The argument @p@. |
b0ab12e6 |
129 | * |
130 | * Use: Initializes a new point. The initial value is the additive |
131 | * identity (which is universal for all curves). |
132 | */ |
133 | |
134 | #define EC_INIT { MP_NEW, MP_NEW, MP_NEW } |
135 | |
136 | #define EC_CREATE(p) do { \ |
137 | ec *_p = (p); \ |
138 | _p->x = _p->y = _p->z = MP_NEW; \ |
139 | } while (0) |
140 | |
41a324a7 |
141 | extern ec *ec_create(ec */*p*/); |
b0ab12e6 |
142 | |
143 | /* --- @ec_destroy@ --- * |
144 | * |
145 | * Arguments: @ec *p@ = pointer to an elliptic-curve point |
146 | * |
147 | * Returns: --- |
148 | * |
149 | * Use: Destroys a point, making it invalid. |
150 | */ |
151 | |
152 | #define EC_DESTROY(p) do { \ |
153 | ec *_p = (p); \ |
154 | if (!EC_ATINF(_p)) { \ |
155 | MP_DROP(_p->x); \ |
156 | MP_DROP(_p->y); \ |
157 | if (_p->z) MP_DROP(_p->z); \ |
158 | } \ |
159 | } while (0) |
160 | |
161 | extern void ec_destroy(ec */*p*/); |
162 | |
163 | /* --- @ec_atinf@ --- * |
164 | * |
165 | * Arguments: @const ec *p@ = pointer to a point |
166 | * |
167 | * Returns: Nonzero if %$p = O$% is the point at infinity, zero |
168 | * otherwise. |
169 | */ |
170 | |
171 | #define EC_ATINF(p) ((p)->x == MP_NEW || (p)->x == MP_NEWSEC) |
172 | |
173 | extern int ec_atinf(const ec */*p*/); |
174 | |
175 | /* --- @ec_setinf@ --- * |
176 | * |
177 | * Arguments: @ec *p@ = pointer to a point |
178 | * |
41a324a7 |
179 | * Returns: The argument @p@. |
b0ab12e6 |
180 | * |
181 | * Use: Sets the given point to be the point %$O$% at infinity. |
182 | */ |
183 | |
184 | #define EC_SETINF(p) do { \ |
185 | ec *_p = (p); \ |
186 | if (!EC_ATINF(_p)) { \ |
187 | MP_DROP(_p->x); \ |
188 | MP_DROP(_p->y); \ |
189 | if (_p->z) MP_DROP(_p->z); \ |
190 | _p->x = _p->y = _p->z = MP_NEW; \ |
191 | _p->y = MP_NEW; \ |
192 | _p->z = MP_NEW; \ |
193 | } \ |
194 | } while (0) |
195 | |
41a324a7 |
196 | extern ec *ec_setinf(ec */*p*/); |
b0ab12e6 |
197 | |
198 | /* --- @ec_copy@ --- * |
199 | * |
200 | * Arguments: @ec *d@ = pointer to destination point |
201 | * @const ec *p@ = pointer to source point |
202 | * |
41a324a7 |
203 | * Returns: The destination @d@. |
b0ab12e6 |
204 | * |
205 | * Use: Creates a copy of an elliptic curve point. |
206 | */ |
207 | |
208 | #define EC_COPY(d, p) do { \ |
209 | ec *_d = (d); \ |
210 | const ec *_p = (p); \ |
211 | if (d != p) { \ |
212 | EC_DESTROY(d); \ |
213 | if (EC_ATINF(p)) \ |
214 | _d->x = _d->y = _d->z = MP_NEW; \ |
215 | else { \ |
b085fd91 |
216 | _d->x = MP_COPY(_p->x); \ |
217 | _d->y = MP_COPY(_p->y); \ |
218 | _d->z = _p->z ? MP_COPY(_p->z) : MP_NEW; \ |
b0ab12e6 |
219 | } \ |
220 | } \ |
221 | } while (0) |
222 | |
41a324a7 |
223 | extern ec *ec_copy(ec */*d*/, const ec */*p*/); |
b0ab12e6 |
224 | |
bc985cef |
225 | /* --- @ec_eq@ --- * |
226 | * |
227 | * Arguments: @const ec *p, *q@ = two points |
228 | * |
229 | * Returns: Nonzero if the points are equal. Compares external-format |
230 | * points. |
231 | */ |
232 | |
233 | #define EC_EQ(p, q) \ |
234 | ((EC_ATINF(p) && EC_ATINF(q)) || \ |
235 | (!EC_ATINF(p) && !EC_ATINF(q) && \ |
236 | MP_EQ((p)->x, (q)->x) && \ |
237 | MP_EQ((p)->y, (q)->y))) |
238 | |
239 | extern int ec_eq(const ec *p, const ec *q); |
240 | |
b0ab12e6 |
241 | /*----- Interesting arithmetic --------------------------------------------*/ |
242 | |
34e4f738 |
243 | /* --- @ec_samep@ --- * |
244 | * |
245 | * Arguments: @ec_curve *c, *d@ = two elliptic curves |
246 | * |
247 | * Returns: Nonzero if the curves are identical (not just isomorphic). |
248 | * |
249 | * Use: Checks for sameness of curves. This function does the full |
250 | * check, not just the curve-type-specific check done by the |
251 | * @sampep@ field operation. |
252 | */ |
253 | |
254 | extern int ec_samep(ec_curve */*c*/, ec_curve */*d*/); |
255 | |
b0ab12e6 |
256 | /* --- @ec_find@ --- * |
257 | * |
258 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
259 | * @ec *d@ = pointer to the destination point |
260 | * @mp *x@ = a possible x-coordinate |
261 | * |
b085fd91 |
262 | * Returns: The destination if OK, or null if no point was found. |
b0ab12e6 |
263 | * |
b085fd91 |
264 | * Use: Finds a point on an elliptic curve with a given |
265 | * x-coordinate. If there is no point with the given |
266 | * %$x$%-coordinate, a null pointer is returned and the |
267 | * destination is left invalid. |
b0ab12e6 |
268 | */ |
269 | |
b085fd91 |
270 | extern ec *ec_find(ec_curve */*c*/, ec */*d*/, mp */*x*/); |
271 | |
bc985cef |
272 | /* --- @ec_rand@ --- * |
273 | * |
274 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
275 | * @ec *d@ = pointer to the destination point |
276 | * @grand *r@ = random number source |
277 | * |
278 | * Returns: The destination @d@. |
279 | * |
280 | * Use: Finds a random point on the given curve. |
281 | */ |
282 | |
283 | extern ec *ec_rand(ec_curve */*c*/, ec */*d*/, grand */*r*/); |
284 | |
b085fd91 |
285 | /* --- @ec_neg@ --- * |
286 | * |
287 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
288 | * @ec *d@ = pointer to the destination point |
289 | * @const ec *p@ = pointer to the operand point |
290 | * |
291 | * Returns: The destination point. |
292 | * |
293 | * Use: Computes the negation of the given point. |
294 | */ |
295 | |
296 | extern ec *ec_neg(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
b0ab12e6 |
297 | |
298 | /* --- @ec_add@ --- * |
299 | * |
300 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
301 | * @ec *d@ = pointer to the destination point |
302 | * @const ec *p, *q@ = pointers to the operand points |
303 | * |
41a324a7 |
304 | * Returns: The destination @d@. |
b0ab12e6 |
305 | * |
306 | * Use: Adds two points on an elliptic curve. |
307 | */ |
308 | |
41a324a7 |
309 | extern ec *ec_add(ec_curve */*c*/, ec */*d*/, |
310 | const ec */*p*/, const ec */*q*/); |
b0ab12e6 |
311 | |
b085fd91 |
312 | /* --- @ec_sub@ --- * |
313 | * |
314 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
315 | * @ec *d@ = pointer to the destination point |
316 | * @const ec *p, *q@ = pointers to the operand points |
317 | * |
318 | * Returns: The destination @d@. |
319 | * |
320 | * Use: Subtracts one point from another on an elliptic curve. |
321 | */ |
322 | |
323 | extern ec *ec_sub(ec_curve */*c*/, ec */*d*/, |
324 | const ec */*p*/, const ec */*q*/); |
325 | |
b0ab12e6 |
326 | /* --- @ec_dbl@ --- * |
327 | * |
328 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
329 | * @ec *d@ = pointer to the destination point |
330 | * @const ec *p@ = pointer to the operand point |
331 | * |
41a324a7 |
332 | * Returns: The destination @d@. |
b0ab12e6 |
333 | * |
334 | * Use: Doubles a point on an elliptic curve. |
335 | */ |
336 | |
41a324a7 |
337 | extern ec *ec_dbl(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
b0ab12e6 |
338 | |
8823192f |
339 | /* --- @ec_check@ --- * |
340 | * |
341 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
342 | * @const ec *p@ = pointer to the point |
343 | * |
344 | * Returns: Zero if OK, nonzero if this is an invalid point. |
345 | * |
346 | * Use: Checks that a point is actually on an elliptic curve. |
347 | */ |
348 | |
349 | extern int ec_check(ec_curve */*c*/, const ec */*p*/); |
350 | |
b085fd91 |
351 | /* --- @ec_mul@, @ec_imul@ --- * |
b0ab12e6 |
352 | * |
353 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
354 | * @ec *d@ = pointer to the destination point |
355 | * @const ec *p@ = pointer to the generator point |
356 | * @mp *n@ = integer multiplier |
357 | * |
41a324a7 |
358 | * Returns: The destination @d@. |
b0ab12e6 |
359 | * |
b085fd91 |
360 | * Use: Multiplies a point by a scalar, returning %$n p$%. The |
361 | * @imul@ variant uses internal representations for argument |
362 | * and result. |
b0ab12e6 |
363 | */ |
364 | |
41a324a7 |
365 | extern ec *ec_mul(ec_curve */*c*/, ec */*d*/, const ec */*p*/, mp */*n*/); |
b085fd91 |
366 | extern ec *ec_imul(ec_curve */*c*/, ec */*d*/, const ec */*p*/, mp */*n*/); |
367 | |
368 | /* --- @ec_mmul@, @ec_immul@ --- * |
369 | * |
370 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
371 | * @ec *d@ = pointer to the destination point |
372 | * @const ec_mulfactor *f@ = pointer to vector of factors |
373 | * @size_t n@ = number of factors |
374 | * |
375 | * Returns: The destination @d@. |
376 | * |
377 | * Use: Does simultaneous point multiplication. The @immul@ variant |
378 | * uses internal representations for arguments and result. |
379 | */ |
380 | |
381 | extern ec *ec_mmul(ec_curve */*c*/, ec */*d*/, |
382 | const ec_mulfactor */*f*/, size_t /*n*/); |
383 | extern ec *ec_immul(ec_curve */*c*/, ec */*d*/, |
384 | const ec_mulfactor */*f*/, size_t /*n*/); |
41a324a7 |
385 | |
386 | /*----- Standard curve operations -----------------------------------------*/ |
387 | |
34e4f738 |
388 | /* --- @ec_stdsamep@ --- * |
389 | * |
390 | * Arguments: @ec_curve *c, *d@ = two elliptic curves |
391 | * |
392 | * Returns: Nonzero if the curves are identical (not just isomorphic). |
393 | * |
394 | * Use: Simple sameness check on @a@ and @b@ curve members. |
395 | */ |
396 | |
397 | extern int ec_stdsamep(ec_curve */*c*/, ec_curve */*d*/); |
398 | |
8823192f |
399 | /* --- @ec_idin@, @ec_idout@, @ec_idfix@ --- * |
41a324a7 |
400 | * |
401 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
402 | * @ec *d@ = pointer to the destination |
403 | * @const ec *p@ = pointer to a source point |
404 | * |
405 | * Returns: The destination @d@. |
406 | * |
407 | * Use: An identity operation if your curve has no internal |
408 | * representation. (The field internal representation is still |
409 | * used.) |
410 | */ |
411 | |
412 | extern ec *ec_idin(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
413 | extern ec *ec_idout(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
8823192f |
414 | extern ec *ec_idfix(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
41a324a7 |
415 | |
8823192f |
416 | /* --- @ec_projin@, @ec_projout@, @ec_projfix@ --- * |
41a324a7 |
417 | * |
418 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
419 | * @ec *d@ = pointer to the destination |
420 | * @const ec *p@ = pointer to a source point |
421 | * |
422 | * Returns: The destination @d@. |
423 | * |
424 | * Use: Conversion functions if your curve operations use a |
425 | * projective representation. |
426 | */ |
427 | |
428 | extern ec *ec_projin(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
429 | extern ec *ec_projout(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
8823192f |
430 | extern ec *ec_projfix(ec_curve */*c*/, ec */*d*/, const ec */*p*/); |
b0ab12e6 |
431 | |
b085fd91 |
432 | /* --- @ec_stdsub@ --- * |
433 | * |
434 | * Arguments: @ec_curve *c@ = pointer to an elliptic curve |
435 | * @ec *d@ = pointer to the destination |
41cb1beb |
436 | * @const ec *p, *q@ = the operand points |
b085fd91 |
437 | * |
438 | * Returns: The destination @d@. |
439 | * |
440 | * Use: Standard point subtraction operation, in terms of negation |
441 | * and addition. This isn't as efficient as a ready-made |
442 | * subtraction operator. |
443 | */ |
444 | |
41cb1beb |
445 | extern ec *ec_stdsub(ec_curve */*c*/, ec */*d*/, |
446 | const ec */*p*/, const ec */*q*/); |
b085fd91 |
447 | |
b0ab12e6 |
448 | /*----- Creating curves ---------------------------------------------------*/ |
449 | |
b085fd91 |
450 | /* --- @ec_destroycurve@ --- * |
451 | * |
452 | * Arguments: @ec_curve *c@ = pointer to an ellptic curve |
453 | * |
454 | * Returns: --- |
455 | * |
456 | * Use: Destroys a description of an elliptic curve. |
457 | */ |
458 | |
459 | extern void ec_destroycurve(ec_curve */*c*/); |
460 | |
461 | /* --- @ec_prime@, @ec_primeproj@ --- * |
b0ab12e6 |
462 | * |
dbfee00a |
463 | * Arguments: @field *f@ = the underlying field for this elliptic curve |
b0ab12e6 |
464 | * @mp *a, *b@ = the coefficients for this curve |
465 | * |
02d7884d |
466 | * Returns: A pointer to the curve, or null. |
b0ab12e6 |
467 | * |
468 | * Use: Creates a curve structure for an elliptic curve defined over |
b085fd91 |
469 | * a prime field. The @primeproj@ variant uses projective |
470 | * coordinates, which can be a win. |
b0ab12e6 |
471 | */ |
472 | |
473 | extern ec_curve *ec_prime(field */*f*/, mp */*a*/, mp */*b*/); |
b085fd91 |
474 | extern ec_curve *ec_primeproj(field */*f*/, mp */*a*/, mp */*b*/); |
b0ab12e6 |
475 | |
ceb3f0c0 |
476 | /* --- @ec_bin@, @ec_binproj@ --- * |
b0ab12e6 |
477 | * |
478 | * Arguments: @field *f@ = the underlying field for this elliptic curve |
479 | * @mp *a, *b@ = the coefficients for this curve |
480 | * |
02d7884d |
481 | * Returns: A pointer to the curve, or null. |
b0ab12e6 |
482 | * |
ceb3f0c0 |
483 | * Use: Creates a curve structure for an elliptic curve defined over |
484 | * a binary field. The @binproj@ variant uses projective |
485 | * coordinates, which can be a win. |
b0ab12e6 |
486 | */ |
487 | |
488 | extern ec_curve *ec_bin(field */*f*/, mp */*a*/, mp */*b*/); |
ceb3f0c0 |
489 | extern ec_curve *ec_binproj(field */*f*/, mp */*a*/, mp */*b*/); |
b0ab12e6 |
490 | |
432c4e18 |
491 | /*----- Curve parameter sets ----------------------------------------------*/ |
492 | |
493 | /* --- @ec_curveparse@ --- * |
494 | * |
495 | * Arguments: @qd_parse *qd@ = parser context |
496 | * |
497 | * Returns: Elliptic curve pointer if OK, or null. |
498 | * |
499 | * Use: Parses an elliptic curve description, which has the form |
500 | * |
501 | * * a field description |
20095408 |
502 | * * an optional `;' |
432c4e18 |
503 | * * `prime', `primeproj', `bin', or `binproj' |
504 | * * an optional `:' |
505 | * * the %$a$% parameter |
506 | * * an optional `,' |
507 | * * the %$b$% parameter |
508 | */ |
509 | |
510 | extern ec_curve *ec_curveparse(qd_parse */*qd*/); |
511 | |
512 | /* --- @ec_ptparse@ --- * |
513 | * |
514 | * Arguments: @qd_parse *qd@ = parser context |
515 | * @ec *p@ = where to put the point |
516 | * |
517 | * Returns: The point address, or null. |
518 | * |
519 | * Use: Parses an elliptic curve point. This has the form |
520 | * |
521 | * * %$x$%-coordinate |
522 | * * optional `,' |
523 | * * %$y$%-coordinate |
524 | */ |
525 | |
526 | extern ec *ec_ptparse(qd_parse */*qd*/, ec */*p*/); |
527 | |
528 | /* --- @ec_infoparse@ --- * |
529 | * |
530 | * Arguments: @qd_parse *qd@ = parser context |
531 | * @ec_info *ei@ = curve information block, currently |
532 | * uninitialized |
533 | * |
534 | * Returns: Zero on success, nonzero on failure. |
535 | * |
536 | * Use: Parses an elliptic curve information string, and stores the |
537 | * information in @ei@. This has the form |
538 | * |
539 | * * elliptic curve description |
20095408 |
540 | * * optional `;' |
432c4e18 |
541 | * * common point |
542 | * * optional `:' |
543 | * * group order |
544 | * * optional `*' |
545 | * * cofactor |
546 | */ |
547 | |
548 | extern int ec_infoparse(qd_parse */*qd*/, ec_info */*ei*/); |
549 | |
7b6d64f1 |
550 | /* --- @ec_infofromdata@ --- * |
551 | * |
552 | * Arguments: @ec_info *ei@ = where to write the information |
553 | * @ecdata *ed@ = raw data |
554 | * |
555 | * Returns: --- |
556 | * |
557 | * Use: Loads elliptic curve information about one of the standard |
558 | * curves. |
559 | */ |
560 | |
561 | struct ecdata; |
562 | extern void ec_infofromdata(ec_info */*ei*/, struct ecdata */*ed*/); |
563 | |
432c4e18 |
564 | /* --- @ec_getinfo@ --- * |
565 | * |
566 | * Arguments: @ec_info *ei@ = where to write the information |
567 | * @const char *p@ = string describing a curve |
568 | * |
569 | * Returns: Null on success, or a pointer to an error message. |
570 | * |
571 | * Use: Parses out information about a curve. The string is either a |
572 | * standard curve name, or a curve info string. |
573 | */ |
574 | |
575 | extern const char *ec_getinfo(ec_info */*ei*/, const char */*p*/); |
576 | |
34e4f738 |
577 | /* --- @ec_sameinfop@ --- * |
578 | * |
579 | * Arguments: @ec_info *ei, *ej@ = two elliptic curve parameter sets |
580 | * |
581 | * Returns: Nonzero if the curves are identical (not just isomorphic). |
582 | * |
583 | * Use: Checks for sameness of curve parameters. |
584 | */ |
585 | |
586 | extern int ec_sameinfop(ec_info */*ei*/, ec_info */*ej*/); |
587 | |
432c4e18 |
588 | /* --- @ec_freeinfo@ --- * |
589 | * |
590 | * Arguments: @ec_info *ei@ = elliptic curve information block to free |
591 | * |
592 | * Returns: --- |
593 | * |
594 | * Use: Frees the information block. |
595 | */ |
596 | |
597 | extern void ec_freeinfo(ec_info */*ei*/); |
598 | |
599 | /* --- @ec_checkinfo@ --- * |
600 | * |
601 | * Arguments: @const ec_info *ei@ = elliptic curve information block |
602 | * |
603 | * Returns: Null if OK, or pointer to error message. |
604 | * |
605 | * Use: Checks an elliptic curve according to the rules in SEC1. |
606 | */ |
607 | |
608 | extern const char *ec_checkinfo(const ec_info */*ei*/, grand */*gr*/); |
609 | |
b0ab12e6 |
610 | /*----- That's all, folks -------------------------------------------------*/ |
611 | |
612 | #ifdef __cplusplus |
613 | } |
614 | #endif |
615 | |
616 | #endif |