diff options
| author | Bodo Möller <bodo@openssl.org> | 2000-11-29 19:26:33 +0000 |
|---|---|---|
| committer | Bodo Möller <bodo@openssl.org> | 2000-11-29 19:26:33 +0000 |
| commit | eb1f1b0a341cbe2c75d8f24b2dc62f4cad05dcec (patch) | |
| tree | 0283e16350c453a812e800021a182dbf98b1d3fa /crypto/bn/bn_kron.c | |
| parent | a9376dbff94c9ddd06639264389ae9777bcb2d30 (diff) | |
Fix BN_kronecker so that it works correctly if 'a' is negative
(we need the two's complement of BN_lsw then).
Diffstat (limited to 'crypto/bn/bn_kron.c')
| -rw-r--r-- | crypto/bn/bn_kron.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/crypto/bn/bn_kron.c b/crypto/bn/bn_kron.c index 20b593e679..0dd8a194cb 100644 --- a/crypto/bn/bn_kron.c +++ b/crypto/bn/bn_kron.c @@ -65,7 +65,7 @@ int BN_kronecker(const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) { int i; - int ret; + int ret = -2; /* avoid 'uninitialized' warning */ int err = 0; BIGNUM *A, *B, *tmp; /* In 'tab', only odd-indexed entries are relevant: @@ -165,7 +165,7 @@ int BN_kronecker(const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) /* Cohen's step 4: */ /* multiply 'ret' by $(-1)^{(A-1)(B-1)/4}$ */ - if (BN_lsw(A) & BN_lsw(B) & 2) + if ((A->neg ? ~BN_lsw(A) : BN_lsw(A)) & BN_lsw(B) & 2) ret = -ret; /* (A, B) := (B mod |A|, |A|) */ |