Index: mozilla/security/nss/lib/freebl/mpi/mplogic.c |
=================================================================== |
--- mozilla/security/nss/lib/freebl/mpi/mplogic.c (revision 191424) |
+++ mozilla/security/nss/lib/freebl/mpi/mplogic.c (working copy) |
@@ -1,433 +0,0 @@ |
-/* |
- * mplogic.c |
- * |
- * Bitwise logical operations on MPI values |
- * |
- * This Source Code Form is subject to the terms of the Mozilla Public |
- * License, v. 2.0. If a copy of the MPL was not distributed with this |
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
-/* $Id: mplogic.c,v 1.16 2012/04/25 14:49:50 gerv%gerv.net Exp $ */ |
- |
-#include "mpi-priv.h" |
-#include "mplogic.h" |
- |
-/* {{{ Lookup table for population count */ |
- |
-static unsigned char bitc[] = { |
- 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, |
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, |
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, |
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, |
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, |
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, |
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, |
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, |
- 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, |
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, |
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, |
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, |
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, |
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, |
- 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, |
- 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8 |
-}; |
- |
-/* }}} */ |
- |
-/*------------------------------------------------------------------------*/ |
-/* |
- mpl_not(a, b) - compute b = ~a |
- mpl_and(a, b, c) - compute c = a & b |
- mpl_or(a, b, c) - compute c = a | b |
- mpl_xor(a, b, c) - compute c = a ^ b |
- */ |
- |
-/* {{{ mpl_not(a, b) */ |
- |
-mp_err mpl_not(mp_int *a, mp_int *b) |
-{ |
- mp_err res; |
- unsigned int ix; |
- |
- ARGCHK(a != NULL && b != NULL, MP_BADARG); |
- |
- if((res = mp_copy(a, b)) != MP_OKAY) |
- return res; |
- |
- /* This relies on the fact that the digit type is unsigned */ |
- for(ix = 0; ix < USED(b); ix++) |
- DIGIT(b, ix) = ~DIGIT(b, ix); |
- |
- s_mp_clamp(b); |
- |
- return MP_OKAY; |
- |
-} /* end mpl_not() */ |
- |
-/* }}} */ |
- |
-/* {{{ mpl_and(a, b, c) */ |
- |
-mp_err mpl_and(mp_int *a, mp_int *b, mp_int *c) |
-{ |
- mp_int *which, *other; |
- mp_err res; |
- unsigned int ix; |
- |
- ARGCHK(a != NULL && b != NULL && c != NULL, MP_BADARG); |
- |
- if(USED(a) <= USED(b)) { |
- which = a; |
- other = b; |
- } else { |
- which = b; |
- other = a; |
- } |
- |
- if((res = mp_copy(which, c)) != MP_OKAY) |
- return res; |
- |
- for(ix = 0; ix < USED(which); ix++) |
- DIGIT(c, ix) &= DIGIT(other, ix); |
- |
- s_mp_clamp(c); |
- |
- return MP_OKAY; |
- |
-} /* end mpl_and() */ |
- |
-/* }}} */ |
- |
-/* {{{ mpl_or(a, b, c) */ |
- |
-mp_err mpl_or(mp_int *a, mp_int *b, mp_int *c) |
-{ |
- mp_int *which, *other; |
- mp_err res; |
- unsigned int ix; |
- |
- ARGCHK(a != NULL && b != NULL && c != NULL, MP_BADARG); |
- |
- if(USED(a) >= USED(b)) { |
- which = a; |
- other = b; |
- } else { |
- which = b; |
- other = a; |
- } |
- |
- if((res = mp_copy(which, c)) != MP_OKAY) |
- return res; |
- |
- for(ix = 0; ix < USED(which); ix++) |
- DIGIT(c, ix) |= DIGIT(other, ix); |
- |
- return MP_OKAY; |
- |
-} /* end mpl_or() */ |
- |
-/* }}} */ |
- |
-/* {{{ mpl_xor(a, b, c) */ |
- |
-mp_err mpl_xor(mp_int *a, mp_int *b, mp_int *c) |
-{ |
- mp_int *which, *other; |
- mp_err res; |
- unsigned int ix; |
- |
- ARGCHK(a != NULL && b != NULL && c != NULL, MP_BADARG); |
- |
- if(USED(a) >= USED(b)) { |
- which = a; |
- other = b; |
- } else { |
- which = b; |
- other = a; |
- } |
- |
- if((res = mp_copy(which, c)) != MP_OKAY) |
- return res; |
- |
- for(ix = 0; ix < USED(which); ix++) |
- DIGIT(c, ix) ^= DIGIT(other, ix); |
- |
- s_mp_clamp(c); |
- |
- return MP_OKAY; |
- |
-} /* end mpl_xor() */ |
- |
-/* }}} */ |
- |
-/*------------------------------------------------------------------------*/ |
-/* |
- mpl_rsh(a, b, d) - b = a >> d |
- mpl_lsh(a, b, d) - b = a << d |
- */ |
- |
-/* {{{ mpl_rsh(a, b, d) */ |
- |
-mp_err mpl_rsh(const mp_int *a, mp_int *b, mp_digit d) |
-{ |
- mp_err res; |
- |
- ARGCHK(a != NULL && b != NULL, MP_BADARG); |
- |
- if((res = mp_copy(a, b)) != MP_OKAY) |
- return res; |
- |
- s_mp_div_2d(b, d); |
- |
- return MP_OKAY; |
- |
-} /* end mpl_rsh() */ |
- |
-/* }}} */ |
- |
-/* {{{ mpl_lsh(a, b, d) */ |
- |
-mp_err mpl_lsh(const mp_int *a, mp_int *b, mp_digit d) |
-{ |
- mp_err res; |
- |
- ARGCHK(a != NULL && b != NULL, MP_BADARG); |
- |
- if((res = mp_copy(a, b)) != MP_OKAY) |
- return res; |
- |
- return s_mp_mul_2d(b, d); |
- |
-} /* end mpl_lsh() */ |
- |
-/* }}} */ |
- |
-/*------------------------------------------------------------------------*/ |
-/* |
- mpl_num_set(a, num) |
- |
- Count the number of set bits in the binary representation of a. |
- Returns MP_OKAY and sets 'num' to be the number of such bits, if |
- possible. If num is NULL, the result is thrown away, but it is |
- not considered an error. |
- |
- mpl_num_clear() does basically the same thing for clear bits. |
- */ |
- |
-/* {{{ mpl_num_set(a, num) */ |
- |
-mp_err mpl_num_set(mp_int *a, int *num) |
-{ |
- unsigned int ix; |
- int db, nset = 0; |
- mp_digit cur; |
- unsigned char reg; |
- |
- ARGCHK(a != NULL, MP_BADARG); |
- |
- for(ix = 0; ix < USED(a); ix++) { |
- cur = DIGIT(a, ix); |
- |
- for(db = 0; db < sizeof(mp_digit); db++) { |
- reg = (unsigned char)(cur >> (CHAR_BIT * db)); |
- |
- nset += bitc[reg]; |
- } |
- } |
- |
- if(num) |
- *num = nset; |
- |
- return MP_OKAY; |
- |
-} /* end mpl_num_set() */ |
- |
-/* }}} */ |
- |
-/* {{{ mpl_num_clear(a, num) */ |
- |
-mp_err mpl_num_clear(mp_int *a, int *num) |
-{ |
- unsigned int ix; |
- int db, nset = 0; |
- mp_digit cur; |
- unsigned char reg; |
- |
- ARGCHK(a != NULL, MP_BADARG); |
- |
- for(ix = 0; ix < USED(a); ix++) { |
- cur = DIGIT(a, ix); |
- |
- for(db = 0; db < sizeof(mp_digit); db++) { |
- reg = (unsigned char)(cur >> (CHAR_BIT * db)); |
- |
- nset += bitc[UCHAR_MAX - reg]; |
- } |
- } |
- |
- if(num) |
- *num = nset; |
- |
- return MP_OKAY; |
- |
- |
-} /* end mpl_num_clear() */ |
- |
-/* }}} */ |
- |
-/*------------------------------------------------------------------------*/ |
-/* |
- mpl_parity(a) |
- |
- Determines the bitwise parity of the value given. Returns MP_EVEN |
- if an even number of digits are set, MP_ODD if an odd number are |
- set. |
- */ |
- |
-/* {{{ mpl_parity(a) */ |
- |
-mp_err mpl_parity(mp_int *a) |
-{ |
- unsigned int ix; |
- int par = 0; |
- mp_digit cur; |
- |
- ARGCHK(a != NULL, MP_BADARG); |
- |
- for(ix = 0; ix < USED(a); ix++) { |
- int shft = (sizeof(mp_digit) * CHAR_BIT) / 2; |
- |
- cur = DIGIT(a, ix); |
- |
- /* Compute parity for current digit */ |
- while(shft != 0) { |
- cur ^= (cur >> shft); |
- shft >>= 1; |
- } |
- cur &= 1; |
- |
- /* XOR with running parity so far */ |
- par ^= cur; |
- } |
- |
- if(par) |
- return MP_ODD; |
- else |
- return MP_EVEN; |
- |
-} /* end mpl_parity() */ |
- |
-/* }}} */ |
- |
-/* |
- mpl_set_bit |
- |
- Returns MP_OKAY or some error code. |
- Grows a if needed to set a bit to 1. |
- */ |
-mp_err mpl_set_bit(mp_int *a, mp_size bitNum, mp_size value) |
-{ |
- mp_size ix; |
- mp_err rv; |
- mp_digit mask; |
- |
- ARGCHK(a != NULL, MP_BADARG); |
- |
- ix = bitNum / MP_DIGIT_BIT; |
- if (ix + 1 > MP_USED(a)) { |
- rv = s_mp_pad(a, ix + 1); |
- if (rv != MP_OKAY) |
- return rv; |
- } |
- |
- bitNum = bitNum % MP_DIGIT_BIT; |
- mask = (mp_digit)1 << bitNum; |
- if (value) |
- MP_DIGIT(a,ix) |= mask; |
- else |
- MP_DIGIT(a,ix) &= ~mask; |
- s_mp_clamp(a); |
- return MP_OKAY; |
-} |
- |
-/* |
- mpl_get_bit |
- |
- returns 0 or 1 or some (negative) error code. |
- */ |
-mp_err mpl_get_bit(const mp_int *a, mp_size bitNum) |
-{ |
- mp_size bit, ix; |
- mp_err rv; |
- |
- ARGCHK(a != NULL, MP_BADARG); |
- |
- ix = bitNum / MP_DIGIT_BIT; |
- ARGCHK(ix <= MP_USED(a) - 1, MP_RANGE); |
- |
- bit = bitNum % MP_DIGIT_BIT; |
- rv = (mp_err)(MP_DIGIT(a, ix) >> bit) & 1; |
- return rv; |
-} |
- |
-/* |
- mpl_get_bits |
- - Extracts numBits bits from a, where the least significant extracted bit |
- is bit lsbNum. Returns a negative value if error occurs. |
- - Because sign bit is used to indicate error, maximum number of bits to |
- be returned is the lesser of (a) the number of bits in an mp_digit, or |
- (b) one less than the number of bits in an mp_err. |
- - lsbNum + numbits can be greater than the number of significant bits in |
- integer a, as long as bit lsbNum is in the high order digit of a. |
- */ |
-mp_err mpl_get_bits(const mp_int *a, mp_size lsbNum, mp_size numBits) |
-{ |
- mp_size rshift = (lsbNum % MP_DIGIT_BIT); |
- mp_size lsWndx = (lsbNum / MP_DIGIT_BIT); |
- mp_digit * digit = MP_DIGITS(a) + lsWndx; |
- mp_digit mask = ((1 << numBits) - 1); |
- |
- ARGCHK(numBits < CHAR_BIT * sizeof mask, MP_BADARG); |
- ARGCHK(MP_HOWMANY(lsbNum, MP_DIGIT_BIT) <= MP_USED(a), MP_RANGE); |
- |
- if ((numBits + lsbNum % MP_DIGIT_BIT <= MP_DIGIT_BIT) || |
- (lsWndx + 1 >= MP_USED(a))) { |
- mask &= (digit[0] >> rshift); |
- } else { |
- mask &= ((digit[0] >> rshift) | (digit[1] << (MP_DIGIT_BIT - rshift))); |
- } |
- return (mp_err)mask; |
-} |
- |
-/* |
- mpl_significant_bits |
- returns number of significnant bits in abs(a). |
- returns 1 if value is zero. |
- */ |
-mp_err mpl_significant_bits(const mp_int *a) |
-{ |
- mp_err bits = 0; |
- int ix; |
- |
- ARGCHK(a != NULL, MP_BADARG); |
- |
- ix = MP_USED(a); |
- for (ix = MP_USED(a); ix > 0; ) { |
- mp_digit d; |
- d = MP_DIGIT(a, --ix); |
- if (d) { |
- while (d) { |
- ++bits; |
- d >>= 1; |
- } |
- break; |
- } |
- } |
- bits += ix * MP_DIGIT_BIT; |
- if (!bits) |
- bits = 1; |
- return bits; |
-} |
- |
-/*------------------------------------------------------------------------*/ |
-/* HERE THERE BE DRAGONS */ |