diff options
Diffstat (limited to 'Cryptlib/OpenSSL/crypto/bn/bn_shift.c')
| -rw-r--r-- | Cryptlib/OpenSSL/crypto/bn/bn_shift.c | 39 |
1 files changed, 27 insertions, 12 deletions
diff --git a/Cryptlib/OpenSSL/crypto/bn/bn_shift.c b/Cryptlib/OpenSSL/crypto/bn/bn_shift.c index 67904c99..9673d9a3 100644 --- a/Cryptlib/OpenSSL/crypto/bn/bn_shift.c +++ b/Cryptlib/OpenSSL/crypto/bn/bn_shift.c @@ -96,7 +96,7 @@ int BN_lshift1(BIGNUM *r, const BIGNUM *a) int BN_rshift1(BIGNUM *r, const BIGNUM *a) { BN_ULONG *ap, *rp, t, c; - int i; + int i, j; bn_check_top(r); bn_check_top(a); @@ -105,21 +105,25 @@ int BN_rshift1(BIGNUM *r, const BIGNUM *a) BN_zero(r); return (1); } + i = a->top; + ap = a->d; + j = i - (ap[i - 1] == 1); if (a != r) { - if (bn_wexpand(r, a->top) == NULL) + if (bn_wexpand(r, j) == NULL) return (0); - r->top = a->top; r->neg = a->neg; } - ap = a->d; rp = r->d; - c = 0; - for (i = a->top - 1; i >= 0; i--) { - t = ap[i]; + t = ap[--i]; + c = (t & 1) ? BN_TBIT : 0; + if (t >>= 1) + rp[i] = t; + while (i > 0) { + t = ap[--i]; rp[i] = ((t >> 1) & BN_MASK2) | c; c = (t & 1) ? BN_TBIT : 0; } - bn_correct_top(r); + r->top = j; bn_check_top(r); return (1); } @@ -133,6 +137,11 @@ int BN_lshift(BIGNUM *r, const BIGNUM *a, int n) bn_check_top(r); bn_check_top(a); + if (n < 0) { + BNerr(BN_F_BN_LSHIFT, BN_R_INVALID_SHIFT); + return 0; + } + r->neg = a->neg; nw = n / BN_BITS2; if (bn_wexpand(r, a->top + nw + 1) == NULL) @@ -170,6 +179,11 @@ int BN_rshift(BIGNUM *r, const BIGNUM *a, int n) bn_check_top(r); bn_check_top(a); + if (n < 0) { + BNerr(BN_F_BN_RSHIFT, BN_R_INVALID_SHIFT); + return 0; + } + nw = n / BN_BITS2; rb = n % BN_BITS2; lb = BN_BITS2 - rb; @@ -177,9 +191,10 @@ int BN_rshift(BIGNUM *r, const BIGNUM *a, int n) BN_zero(r); return (1); } + i = (BN_num_bits(a) - n + (BN_BITS2 - 1)) / BN_BITS2; if (r != a) { r->neg = a->neg; - if (bn_wexpand(r, a->top - nw + 1) == NULL) + if (bn_wexpand(r, i) == NULL) return (0); } else { if (n == 0) @@ -189,7 +204,7 @@ int BN_rshift(BIGNUM *r, const BIGNUM *a, int n) f = &(a->d[nw]); t = r->d; j = a->top - nw; - r->top = j; + r->top = i; if (rb == 0) { for (i = j; i != 0; i--) @@ -201,9 +216,9 @@ int BN_rshift(BIGNUM *r, const BIGNUM *a, int n) l = *(f++); *(t++) = (tmp | (l << lb)) & BN_MASK2; } - *(t++) = (l >> rb) & BN_MASK2; + if ((l = (l >> rb) & BN_MASK2)) + *(t) = l; } - bn_correct_top(r); bn_check_top(r); return (1); } |