diff options
Diffstat (limited to 'frozen_deps/Cryptodome/Math/_IntegerGMP.py')
| -rw-r--r-- | frozen_deps/Cryptodome/Math/_IntegerGMP.py | 96 |
1 files changed, 75 insertions, 21 deletions
diff --git a/frozen_deps/Cryptodome/Math/_IntegerGMP.py b/frozen_deps/Cryptodome/Math/_IntegerGMP.py index c860020..3ab7c59 100644 --- a/frozen_deps/Cryptodome/Math/_IntegerGMP.py +++ b/frozen_deps/Cryptodome/Math/_IntegerGMP.py @@ -35,7 +35,7 @@ from Cryptodome.Util.py3compat import tobytes, is_native_int from Cryptodome.Util._raw_api import (backend, load_lib, get_raw_buffer, get_c_string, null_pointer, create_string_buffer, - c_ulong, c_size_t) + c_ulong, c_size_t, c_uint8_ptr) from ._IntegerBase import IntegerBase @@ -43,12 +43,14 @@ gmp_defs = """typedef unsigned long UNIX_ULONG; typedef struct { int a; int b; void *c; } MPZ; typedef MPZ mpz_t[1]; typedef UNIX_ULONG mp_bitcnt_t; + void __gmpz_init (mpz_t x); void __gmpz_init_set (mpz_t rop, const mpz_t op); void __gmpz_init_set_ui (mpz_t rop, UNIX_ULONG op); - int __gmp_sscanf (const char *s, const char *fmt, ...); + + UNIX_ULONG __gmpz_get_ui (const mpz_t op); void __gmpz_set (mpz_t rop, const mpz_t op); - int __gmp_snprintf (uint8_t *buf, size_t size, const char *fmt, ...); + void __gmpz_set_ui (mpz_t rop, UNIX_ULONG op); void __gmpz_add (mpz_t rop, const mpz_t op1, const mpz_t op2); void __gmpz_add_ui (mpz_t rop, const mpz_t op1, UNIX_ULONG op2); void __gmpz_sub_ui (mpz_t rop, const mpz_t op1, UNIX_ULONG op2); @@ -156,28 +158,58 @@ class IntegerGMP(IntegerBase): if isinstance(value, float): raise ValueError("A floating point type is not a natural number") - self._initialized = True - if is_native_int(value): _gmp.mpz_init(self._mpz_p) - result = _gmp.gmp_sscanf(tobytes(str(value)), b"%Zd", self._mpz_p) - if result != 1: - raise ValueError("Error converting '%d'" % value) + self._initialized = True + if value == 0: + return + + tmp = new_mpz() + _gmp.mpz_init(tmp) + + try: + positive = value >= 0 + reduce = abs(value) + slots = (reduce.bit_length() - 1) // 32 + 1 + + while slots > 0: + slots = slots - 1 + _gmp.mpz_set_ui(tmp, + c_ulong(0xFFFFFFFF & (reduce >> (slots * 32)))) + _gmp.mpz_mul_2exp(tmp, tmp, c_ulong(slots * 32)) + _gmp.mpz_add(self._mpz_p, self._mpz_p, tmp) + finally: + _gmp.mpz_clear(tmp) + + if not positive: + _gmp.mpz_neg(self._mpz_p, self._mpz_p) + elif isinstance(value, IntegerGMP): _gmp.mpz_init_set(self._mpz_p, value._mpz_p) + self._initialized = True else: raise NotImplementedError + # Conversions def __int__(self): - # buf will contain the integer encoded in decimal plus the trailing - # zero, and possibly the negative sign. - # dig10(x) < log10(x) + 1 = log2(x)/log2(10) + 1 < log2(x)/3 + 1 - buf_len = _gmp.mpz_sizeinbase(self._mpz_p, 2) // 3 + 3 - buf = create_string_buffer(buf_len) + tmp = new_mpz() + _gmp.mpz_init_set(tmp, self._mpz_p) - _gmp.gmp_snprintf(buf, c_size_t(buf_len), b"%Zd", self._mpz_p) - return int(get_c_string(buf)) + try: + value = 0 + slot = 0 + while _gmp.mpz_cmp(tmp, self._zero_mpz_p) != 0: + lsb = _gmp.mpz_get_ui(tmp) & 0xFFFFFFFF + value |= lsb << (slot * 32) + _gmp.mpz_tdiv_q_2exp(tmp, tmp, c_ulong(32)) + slot = slot + 1 + finally: + _gmp.mpz_clear(tmp) + + if self < 0: + value = -value + return int(value) def __str__(self): return str(int(self)) @@ -193,7 +225,7 @@ class IntegerGMP(IntegerBase): def __index__(self): return int(self) - def to_bytes(self, block_size=0): + def to_bytes(self, block_size=0, byteorder='big'): """Convert the number into a byte string. This method encodes the number in network order and prepends @@ -204,6 +236,8 @@ class IntegerGMP(IntegerBase): block_size : integer The exact size the output byte string must have. If zero, the string has the minimal length. + byteorder : string + 'big' for big-endian integers (default), 'little' for litte-endian. :Returns: A byte string. :Raise ValueError: @@ -217,9 +251,10 @@ class IntegerGMP(IntegerBase): buf_len = (_gmp.mpz_sizeinbase(self._mpz_p, 2) + 7) // 8 if buf_len > block_size > 0: raise ValueError("Number is too big to convert to byte string" - "of prescribed length") + " of prescribed length") buf = create_string_buffer(buf_len) + _gmp.mpz_export( buf, null_pointer, # Ignore countp @@ -229,20 +264,39 @@ class IntegerGMP(IntegerBase): c_size_t(0), # No nails self._mpz_p) - return b'\x00' * max(0, block_size - buf_len) + get_raw_buffer(buf) + result = b'\x00' * max(0, block_size - buf_len) + get_raw_buffer(buf) + if byteorder == 'big': + pass + elif byteorder == 'little': + result = bytearray(result) + result.reverse() + result = bytes(result) + else: + raise ValueError("Incorrect byteorder") + return result @staticmethod - def from_bytes(byte_string): + def from_bytes(byte_string, byteorder='big'): """Convert a byte string into a number. :Parameters: byte_string : byte string The input number, encoded in network order. It can only be non-negative. + byteorder : string + 'big' for big-endian integers (default), 'little' for litte-endian. + :Return: The ``Integer`` object carrying the same value as the input. """ result = IntegerGMP(0) + if byteorder == 'big': + pass + elif byteorder == 'little': + byte_string = bytearray(byte_string) + byte_string.reverse() + else: + raise ValueError("Incorrect byteorder") _gmp.mpz_import( result._mpz_p, c_size_t(len(byte_string)), # Amount of words to read @@ -250,7 +304,7 @@ class IntegerGMP(IntegerBase): c_size_t(1), # Each word is 1 byte long 0, # Endianess within a word - not relevant c_size_t(0), # No nails - byte_string) + c_uint8_ptr(byte_string)) return result # Relations @@ -692,7 +746,7 @@ class IntegerGMP(IntegerBase): if not isinstance(n, IntegerGMP): n = IntegerGMP(n) if n <= 0 or n.is_even(): - raise ValueError("n must be positive even for the Jacobi symbol") + raise ValueError("n must be positive odd for the Jacobi symbol") return _gmp.mpz_jacobi(a._mpz_p, n._mpz_p) # Clean-up |