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LibCrypto: Add UnsignedBigInteger multiplication

Also added documentation for the runtime complexity of some operations.
This commit is contained in:
Itamar 2020-04-08 19:04:36 +03:00 committed by Andreas Kling
parent 2843dce498
commit 2959c4a5e9
3 changed files with 150 additions and 4 deletions

View file

@ -33,14 +33,23 @@ namespace Crypto {
class UnsignedBigInteger {
public:
UnsignedBigInteger(u32 x) { m_words.append(x); }
UnsignedBigInteger(AK::Vector<u32>&& words)
: m_words(words)
{
}
UnsignedBigInteger() {}
static UnsignedBigInteger create_invalid();
const AK::Vector<u32>& words() const { return m_words; }
UnsignedBigInteger add(const UnsignedBigInteger& other);
UnsignedBigInteger sub(const UnsignedBigInteger& other);
UnsignedBigInteger add(const UnsignedBigInteger& other) const;
UnsignedBigInteger sub(const UnsignedBigInteger& other) const;
UnsignedBigInteger multiply(const UnsignedBigInteger& other) const;
UnsignedBigInteger shift_left(size_t num_bits) const;
UnsignedBigInteger shift_left_by_n_words(const size_t number_of_words) const;
size_t length() const { return m_words.size(); }
@ -54,6 +63,9 @@ public:
bool is_invalid() const { return m_is_invalid; }
private:
u32 shift_left_get_one_word(const size_t num_bits, const size_t result_word_index) const;
static constexpr size_t BITS_IN_WORD = 32;
AK::Vector<u32> m_words;
// Used to indicate a negative result, or a result of an invalid operation