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author | tb <> | 2024-12-12 10:02:00 +0000 |
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committer | tb <> | 2024-12-12 10:02:00 +0000 |
commit | fd906c7b27573203602764309c3cf5faaefdf573 (patch) | |
tree | b24c8788789857e07c8948e204ab0c205d10149c /src | |
parent | 0073d22328d043ee79dbaa9705605bcc23456d4a (diff) | |
download | openbsd-fd906c7b27573203602764309c3cf5faaefdf573.tar.gz openbsd-fd906c7b27573203602764309c3cf5faaefdf573.tar.bz2 openbsd-fd906c7b27573203602764309c3cf5faaefdf573.zip |
Rewrite a comment to use p rather than q
Diffstat (limited to 'src')
-rw-r--r-- | src/lib/libcrypto/ec/ec_lib.c | 20 |
1 files changed, 10 insertions, 10 deletions
diff --git a/src/lib/libcrypto/ec/ec_lib.c b/src/lib/libcrypto/ec/ec_lib.c index 9f1a742d38..6644c4dfc7 100644 --- a/src/lib/libcrypto/ec/ec_lib.c +++ b/src/lib/libcrypto/ec/ec_lib.c | |||
@@ -1,4 +1,4 @@ | |||
1 | /* $OpenBSD: ec_lib.c,v 1.90 2024/12/12 10:00:15 tb Exp $ */ | 1 | /* $OpenBSD: ec_lib.c,v 1.91 2024/12/12 10:02:00 tb Exp $ */ |
2 | /* | 2 | /* |
3 | * Originally written by Bodo Moeller for the OpenSSL project. | 3 | * Originally written by Bodo Moeller for the OpenSSL project. |
4 | */ | 4 | */ |
@@ -227,16 +227,16 @@ ec_group_get_field_type(const EC_GROUP *group) | |||
227 | 227 | ||
228 | /* | 228 | /* |
229 | * If there is a user-provided cofactor, sanity check and use it. Otherwise | 229 | * If there is a user-provided cofactor, sanity check and use it. Otherwise |
230 | * try computing the cofactor from generator order n and field cardinality q. | 230 | * try computing the cofactor from generator order n and field cardinality p. |
231 | * This works for all curves of cryptographic interest. | 231 | * This works for all curves of cryptographic interest. |
232 | * | 232 | * |
233 | * Hasse's theorem: | h * n - (q + 1) | <= 2 * sqrt(q) | 233 | * Hasse's theorem: | h * n - (p + 1) | <= 2 * sqrt(p) |
234 | * | 234 | * |
235 | * So: h_min = (q + 1 - 2*sqrt(q)) / n and h_max = (q + 1 + 2*sqrt(q)) / n and | 235 | * So: h_min = (p + 1 - 2*sqrt(p)) / n and h_max = (p + 1 + 2*sqrt(p)) / n and |
236 | * therefore h_max - h_min = 4*sqrt(q) / n. So if n > 4*sqrt(q) holds, there is | 236 | * therefore h_max - h_min = 4*sqrt(p) / n. So if n > 4*sqrt(p) holds, there is |
237 | * only one possible value for h: | 237 | * only one possible value for h: |
238 | * | 238 | * |
239 | * h = \lfloor (h_min + h_max)/2 \rceil = \lfloor (q + 1)/n \rceil | 239 | * h = \lfloor (h_min + h_max)/2 \rceil = \lfloor (p + 1)/n \rceil |
240 | * | 240 | * |
241 | * Otherwise, zero cofactor and return success. | 241 | * Otherwise, zero cofactor and return success. |
242 | */ | 242 | */ |
@@ -273,14 +273,14 @@ ec_set_cofactor(EC_GROUP *group, const BIGNUM *in_cofactor) | |||
273 | 273 | ||
274 | /* | 274 | /* |
275 | * If the cofactor is too large, we cannot guess it and default to zero. | 275 | * If the cofactor is too large, we cannot guess it and default to zero. |
276 | * The RHS of below is a strict overestimate of log(4 * sqrt(q)). | 276 | * The RHS of below is a strict overestimate of log(4 * sqrt(p)). |
277 | */ | 277 | */ |
278 | if (BN_num_bits(&group->order) <= (BN_num_bits(&group->p) + 1) / 2 + 3) | 278 | if (BN_num_bits(&group->order) <= (BN_num_bits(&group->p) + 1) / 2 + 3) |
279 | goto done; | 279 | goto done; |
280 | 280 | ||
281 | /* | 281 | /* |
282 | * Compute | 282 | * Compute |
283 | * h = \lfloor (q + 1)/n \rceil = \lfloor (q + 1 + n/2) / n \rfloor. | 283 | * h = \lfloor (p + 1)/n \rceil = \lfloor (p + 1 + n/2) / n \rfloor. |
284 | */ | 284 | */ |
285 | 285 | ||
286 | /* h = n/2 */ | 286 | /* h = n/2 */ |
@@ -289,10 +289,10 @@ ec_set_cofactor(EC_GROUP *group, const BIGNUM *in_cofactor) | |||
289 | /* h = 1 + n/2 */ | 289 | /* h = 1 + n/2 */ |
290 | if (!BN_add_word(cofactor, 1)) | 290 | if (!BN_add_word(cofactor, 1)) |
291 | goto err; | 291 | goto err; |
292 | /* h = q + 1 + n/2 */ | 292 | /* h = p + 1 + n/2 */ |
293 | if (!BN_add(cofactor, cofactor, &group->p)) | 293 | if (!BN_add(cofactor, cofactor, &group->p)) |
294 | goto err; | 294 | goto err; |
295 | /* h = (q + 1 + n/2) / n */ | 295 | /* h = (p + 1 + n/2) / n */ |
296 | if (!BN_div_ct(cofactor, NULL, cofactor, &group->order, ctx)) | 296 | if (!BN_div_ct(cofactor, NULL, cofactor, &group->order, ctx)) |
297 | goto err; | 297 | goto err; |
298 | 298 | ||