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author | Jung-uk Kim <jkim@FreeBSD.org> | 2022-03-15 22:18:15 +0000 |
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committer | Jung-uk Kim <jkim@FreeBSD.org> | 2022-03-15 22:18:15 +0000 |
commit | d6d3d400982465ee2c394caa850ba51c537b5a09 (patch) | |
tree | b585b42a59bad0b1d2f9161d22da3b590692ea52 /crypto/bn/bn_sqrt.c | |
parent | 56eae1b760adf10835560a9ee595549a1f10410f (diff) | |
download | src-d6d3d400982465ee2c394caa850ba51c537b5a09.tar.gz src-d6d3d400982465ee2c394caa850ba51c537b5a09.zip |
Import OpenSSL 1.1.1nvendor/openssl/1.1.1n
Diffstat (limited to 'crypto/bn/bn_sqrt.c')
-rw-r--r-- | crypto/bn/bn_sqrt.c | 32 |
1 files changed, 19 insertions, 13 deletions
diff --git a/crypto/bn/bn_sqrt.c b/crypto/bn/bn_sqrt.c index 1723d5ded5a8..6a42ce8a9413 100644 --- a/crypto/bn/bn_sqrt.c +++ b/crypto/bn/bn_sqrt.c @@ -1,5 +1,5 @@ /* - * Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 2000-2022 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy @@ -14,7 +14,8 @@ BIGNUM *BN_mod_sqrt(BIGNUM *in, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx) /* * Returns 'ret' such that ret^2 == a (mod p), using the Tonelli/Shanks * algorithm (cf. Henri Cohen, "A Course in Algebraic Computational Number - * Theory", algorithm 1.5.1). 'p' must be prime! + * Theory", algorithm 1.5.1). 'p' must be prime, otherwise an error or + * an incorrect "result" will be returned. */ { BIGNUM *ret = in; @@ -301,18 +302,23 @@ BIGNUM *BN_mod_sqrt(BIGNUM *in, const BIGNUM *a, const BIGNUM *p, BN_CTX *ctx) goto vrfy; } - /* find smallest i such that b^(2^i) = 1 */ - i = 1; - if (!BN_mod_sqr(t, b, p, ctx)) - goto end; - while (!BN_is_one(t)) { - i++; - if (i == e) { - BNerr(BN_F_BN_MOD_SQRT, BN_R_NOT_A_SQUARE); - goto end; + /* Find the smallest i, 0 < i < e, such that b^(2^i) = 1. */ + for (i = 1; i < e; i++) { + if (i == 1) { + if (!BN_mod_sqr(t, b, p, ctx)) + goto end; + + } else { + if (!BN_mod_mul(t, t, t, p, ctx)) + goto end; } - if (!BN_mod_mul(t, t, t, p, ctx)) - goto end; + if (BN_is_one(t)) + break; + } + /* If not found, a is not a square or p is not prime. */ + if (i >= e) { + BNerr(BN_F_BN_MOD_SQRT, BN_R_NOT_A_SQUARE); + goto end; } /* t := y^2^(e - i - 1) */ |