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-rw-r--r--src/math/bigint/bigint.cpp350
1 files changed, 0 insertions, 350 deletions
diff --git a/src/math/bigint/bigint.cpp b/src/math/bigint/bigint.cpp
deleted file mode 100644
index 45c351256..000000000
--- a/src/math/bigint/bigint.cpp
+++ /dev/null
@@ -1,350 +0,0 @@
-/*
-* BigInt Base
-* (C) 1999-2011,2012 Jack Lloyd
-*
-* Distributed under the terms of the Botan license
-*/
-
-#include <botan/bigint.h>
-#include <botan/internal/mp_core.h>
-#include <botan/get_byte.h>
-#include <botan/parsing.h>
-#include <botan/internal/rounding.h>
-
-namespace Botan {
-
-/*
-* Construct a BigInt from a regular number
-*/
-BigInt::BigInt(u64bit n)
- {
- set_sign(Positive);
-
- if(n == 0)
- return;
-
- const size_t limbs_needed = sizeof(u64bit) / sizeof(word);
-
- m_reg.resize(4*limbs_needed);
- for(size_t i = 0; i != limbs_needed; ++i)
- m_reg[i] = ((n >> (i*MP_WORD_BITS)) & MP_WORD_MASK);
- }
-
-/*
-* Construct a BigInt of the specified size
-*/
-BigInt::BigInt(Sign s, size_t size)
- {
- m_reg.resize(round_up<size_t>(size, 8));
- m_signedness = s;
- }
-
-/*
-* Copy constructor
-*/
-BigInt::BigInt(const BigInt& other)
- {
- m_reg = other.m_reg;
- m_signedness = other.m_signedness;
- }
-
-/*
-* Construct a BigInt from a string
-*/
-BigInt::BigInt(const std::string& str)
- {
- Base base = Decimal;
- size_t markers = 0;
- bool negative = false;
-
- if(str.length() > 0 && str[0] == '-')
- {
- markers += 1;
- negative = true;
- }
-
- if(str.length() > markers + 2 && str[markers ] == '0' &&
- str[markers + 1] == 'x')
- {
- markers += 2;
- base = Hexadecimal;
- }
-
- *this = decode(reinterpret_cast<const byte*>(str.data()) + markers,
- str.length() - markers, base);
-
- if(negative) set_sign(Negative);
- else set_sign(Positive);
- }
-
-/*
-* Construct a BigInt from an encoded BigInt
-*/
-BigInt::BigInt(const byte input[], size_t length, Base base)
- {
- set_sign(Positive);
- *this = decode(input, length, base);
- }
-
-/*
-* Construct a BigInt from an encoded BigInt
-*/
-BigInt::BigInt(RandomNumberGenerator& rng, size_t bits)
- {
- set_sign(Positive);
- randomize(rng, bits);
- }
-
-/*
-* Grow the internal storage
-*/
-void BigInt::grow_to(size_t n)
- {
- if(n > size())
- m_reg.resize(round_up<size_t>(n, 8));
- }
-
-/*
-* Comparison Function
-*/
-s32bit BigInt::cmp(const BigInt& other, bool check_signs) const
- {
- if(check_signs)
- {
- if(other.is_positive() && this->is_negative())
- return -1;
-
- if(other.is_negative() && this->is_positive())
- return 1;
-
- if(other.is_negative() && this->is_negative())
- return (-bigint_cmp(this->data(), this->sig_words(),
- other.data(), other.sig_words()));
- }
-
- return bigint_cmp(this->data(), this->sig_words(),
- other.data(), other.sig_words());
- }
-
-/*
-* Return byte n of this number
-*/
-byte BigInt::byte_at(size_t n) const
- {
- const size_t WORD_BYTES = sizeof(word);
- size_t word_num = n / WORD_BYTES, byte_num = n % WORD_BYTES;
- if(word_num >= size())
- return 0;
- else
- return get_byte(WORD_BYTES - byte_num - 1, m_reg[word_num]);
- }
-
-/*
-* Return bit n of this number
-*/
-bool BigInt::get_bit(size_t n) const
- {
- return ((word_at(n / MP_WORD_BITS) >> (n % MP_WORD_BITS)) & 1);
- }
-
-/*
-* Return bits {offset...offset+length}
-*/
-u32bit BigInt::get_substring(size_t offset, size_t length) const
- {
- if(length > 32)
- throw Invalid_Argument("BigInt::get_substring: Substring size too big");
-
- u64bit piece = 0;
- for(size_t i = 0; i != 8; ++i)
- {
- const byte part = byte_at((offset / 8) + (7-i));
- piece = (piece << 8) | part;
- }
-
- const u64bit mask = (static_cast<u64bit>(1) << length) - 1;
- const size_t shift = (offset % 8);
-
- return static_cast<u32bit>((piece >> shift) & mask);
- }
-
-/*
-* Convert this number to a u32bit, if possible
-*/
-u32bit BigInt::to_u32bit() const
- {
- if(is_negative())
- throw Encoding_Error("BigInt::to_u32bit: Number is negative");
- if(bits() >= 32)
- throw Encoding_Error("BigInt::to_u32bit: Number is too big to convert");
-
- u32bit out = 0;
- for(u32bit j = 0; j != 4; ++j)
- out = (out << 8) | byte_at(3-j);
- return out;
- }
-
-/*
-* Set bit number n
-*/
-void BigInt::set_bit(size_t n)
- {
- const size_t which = n / MP_WORD_BITS;
- const word mask = static_cast<word>(1) << (n % MP_WORD_BITS);
- if(which >= size()) grow_to(which + 1);
- m_reg[which] |= mask;
- }
-
-/*
-* Clear bit number n
-*/
-void BigInt::clear_bit(size_t n)
- {
- const size_t which = n / MP_WORD_BITS;
- const word mask = static_cast<word>(1) << (n % MP_WORD_BITS);
- if(which < size())
- m_reg[which] &= ~mask;
- }
-
-/*
-* Clear all but the lowest n bits
-*/
-void BigInt::mask_bits(size_t n)
- {
- if(n == 0) { clear(); return; }
- if(n >= bits()) return;
-
- const size_t top_word = n / MP_WORD_BITS;
- const word mask = (static_cast<word>(1) << (n % MP_WORD_BITS)) - 1;
-
- if(top_word < size())
- clear_mem(&m_reg[top_word+1], size() - (top_word + 1));
-
- m_reg[top_word] &= mask;
- }
-
-/*
-* Count how many bytes are being used
-*/
-size_t BigInt::bytes() const
- {
- return (bits() + 7) / 8;
- }
-
-/*
-* Count how many bits are being used
-*/
-size_t BigInt::bits() const
- {
- const size_t words = sig_words();
-
- if(words == 0)
- return 0;
-
- size_t full_words = words - 1, top_bits = MP_WORD_BITS;
- word top_word = word_at(full_words), mask = MP_WORD_TOP_BIT;
-
- while(top_bits && ((top_word & mask) == 0))
- { mask >>= 1; top_bits--; }
-
- return (full_words * MP_WORD_BITS + top_bits);
- }
-
-/*
-* Calcluate the size in a certain base
-*/
-size_t BigInt::encoded_size(Base base) const
- {
- static const double LOG_2_BASE_10 = 0.30102999566;
-
- if(base == Binary)
- return bytes();
- else if(base == Hexadecimal)
- return 2*bytes();
- else if(base == Decimal)
- return static_cast<size_t>((bits() * LOG_2_BASE_10) + 1);
- else
- throw Invalid_Argument("Unknown base for BigInt encoding");
- }
-
-/*
-* Set the sign
-*/
-void BigInt::set_sign(Sign s)
- {
- if(is_zero())
- m_signedness = Positive;
- else
- m_signedness = s;
- }
-
-/*
-* Reverse the value of the sign flag
-*/
-void BigInt::flip_sign()
- {
- set_sign(reverse_sign());
- }
-
-/*
-* Return the opposite value of the current sign
-*/
-BigInt::Sign BigInt::reverse_sign() const
- {
- if(sign() == Positive)
- return Negative;
- return Positive;
- }
-
-/*
-* Return the negation of this number
-*/
-BigInt BigInt::operator-() const
- {
- BigInt x = (*this);
- x.flip_sign();
- return x;
- }
-
-/*
-* Return the absolute value of this number
-*/
-BigInt BigInt::abs() const
- {
- BigInt x = (*this);
- x.set_sign(Positive);
- return x;
- }
-
-/*
-* Encode this number into bytes
-*/
-void BigInt::binary_encode(byte output[]) const
- {
- const size_t sig_bytes = bytes();
- for(size_t i = 0; i != sig_bytes; ++i)
- output[sig_bytes-i-1] = byte_at(i);
- }
-
-/*
-* Set this number to the value in buf
-*/
-void BigInt::binary_decode(const byte buf[], size_t length)
- {
- const size_t WORD_BYTES = sizeof(word);
-
- clear();
- m_reg.resize(round_up<size_t>((length / WORD_BYTES) + 1, 8));
-
- for(size_t i = 0; i != length / WORD_BYTES; ++i)
- {
- const size_t top = length - WORD_BYTES*i;
- for(size_t j = WORD_BYTES; j > 0; --j)
- m_reg[i] = (m_reg[i] << 8) | buf[top - j];
- }
-
- for(size_t i = 0; i != length % WORD_BYTES; ++i)
- m_reg[length / WORD_BYTES] = (m_reg[length / WORD_BYTES] << 8) | buf[i];
- }
-
-}