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-rw-r--r--src/libs/3rdparty/botan/src/lib/pubkey/ec_group/point_gfp.cpp727
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diff --git a/src/libs/3rdparty/botan/src/lib/pubkey/ec_group/point_gfp.cpp b/src/libs/3rdparty/botan/src/lib/pubkey/ec_group/point_gfp.cpp
deleted file mode 100644
index 77803de78f..0000000000
--- a/src/libs/3rdparty/botan/src/lib/pubkey/ec_group/point_gfp.cpp
+++ /dev/null
@@ -1,727 +0,0 @@
-/*
-* Point arithmetic on elliptic curves over GF(p)
-*
-* (C) 2007 Martin Doering, Christoph Ludwig, Falko Strenzke
-* 2008-2011,2012,2014,2015 Jack Lloyd
-*
-* Botan is released under the Simplified BSD License (see license.txt)
-*/
-
-#include <botan/point_gfp.h>
-#include <botan/numthry.h>
-#include <botan/rng.h>
-#include <botan/internal/rounding.h>
-
-namespace Botan {
-
-PointGFp::PointGFp(const CurveGFp& curve) :
- m_curve(curve),
- m_coord_x(0),
- m_coord_y(curve.get_1_rep()),
- m_coord_z(0)
- {
- // Assumes Montgomery rep of zero is zero
- }
-
-PointGFp::PointGFp(const CurveGFp& curve, const BigInt& x, const BigInt& y) :
- m_curve(curve),
- m_coord_x(x),
- m_coord_y(y),
- m_coord_z(m_curve.get_1_rep())
- {
- if(x <= 0 || x >= curve.get_p())
- throw Invalid_Argument("Invalid PointGFp affine x");
- if(y <= 0 || y >= curve.get_p())
- throw Invalid_Argument("Invalid PointGFp affine y");
-
- secure_vector<word> monty_ws(m_curve.get_ws_size());
- m_curve.to_rep(m_coord_x, monty_ws);
- m_curve.to_rep(m_coord_y, monty_ws);
- }
-
-void PointGFp::randomize_repr(RandomNumberGenerator& rng)
- {
- secure_vector<word> ws(m_curve.get_ws_size());
- randomize_repr(rng, ws);
- }
-
-void PointGFp::randomize_repr(RandomNumberGenerator& rng, secure_vector<word>& ws)
- {
- const BigInt mask = BigInt::random_integer(rng, 2, m_curve.get_p());
-
- /*
- * No reason to convert this to Montgomery representation first,
- * just pretend the random mask was chosen as Redc(mask) and the
- * random mask we generated above is in the Montgomery
- * representation.
- * //m_curve.to_rep(mask, ws);
- */
- const BigInt mask2 = m_curve.sqr_to_tmp(mask, ws);
- const BigInt mask3 = m_curve.mul_to_tmp(mask2, mask, ws);
-
- m_coord_x = m_curve.mul_to_tmp(m_coord_x, mask2, ws);
- m_coord_y = m_curve.mul_to_tmp(m_coord_y, mask3, ws);
- m_coord_z = m_curve.mul_to_tmp(m_coord_z, mask, ws);
- }
-
-namespace {
-
-inline void resize_ws(std::vector<BigInt>& ws_bn, size_t cap_size)
- {
- BOTAN_ASSERT(ws_bn.size() >= PointGFp::WORKSPACE_SIZE,
- "Expected size for PointGFp workspace");
-
- for(size_t i = 0; i != ws_bn.size(); ++i)
- if(ws_bn[i].size() < cap_size)
- ws_bn[i].get_word_vector().resize(cap_size);
- }
-
-inline bool all_zeros(const word x[], size_t len)
- {
- word z = 0;
- for(size_t i = 0; i != len; ++i)
- z |= x[i];
- return (z == 0);
- }
-
-}
-
-void PointGFp::add_affine(const word x_words[], size_t x_size,
- const word y_words[], size_t y_size,
- std::vector<BigInt>& ws_bn)
- {
- if(all_zeros(x_words, x_size) && all_zeros(y_words, y_size))
- return;
-
- if(is_zero())
- {
- m_coord_x.set_words(x_words, x_size);
- m_coord_y.set_words(y_words, y_size);
- m_coord_z = m_curve.get_1_rep();
- return;
- }
-
- resize_ws(ws_bn, m_curve.get_ws_size());
-
- secure_vector<word>& ws = ws_bn[0].get_word_vector();
- secure_vector<word>& sub_ws = ws_bn[1].get_word_vector();
-
- BigInt& T0 = ws_bn[2];
- BigInt& T1 = ws_bn[3];
- BigInt& T2 = ws_bn[4];
- BigInt& T3 = ws_bn[5];
- BigInt& T4 = ws_bn[6];
-
- /*
- https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-1998-cmo-2
- simplified with Z2 = 1
- */
-
- const BigInt& p = m_curve.get_p();
-
- m_curve.sqr(T3, m_coord_z, ws); // z1^2
- m_curve.mul(T4, x_words, x_size, T3, ws); // x2*z1^2
-
- m_curve.mul(T2, m_coord_z, T3, ws); // z1^3
- m_curve.mul(T0, y_words, y_size, T2, ws); // y2*z1^3
-
- T4.mod_sub(m_coord_x, p, sub_ws); // x2*z1^2 - x1*z2^2
-
- T0.mod_sub(m_coord_y, p, sub_ws);
-
- if(T4.is_zero())
- {
- if(T0.is_zero())
- {
- mult2(ws_bn);
- return;
- }
-
- // setting to zero:
- m_coord_x = 0;
- m_coord_y = m_curve.get_1_rep();
- m_coord_z = 0;
- return;
- }
-
- m_curve.sqr(T2, T4, ws);
-
- m_curve.mul(T3, m_coord_x, T2, ws);
-
- m_curve.mul(T1, T2, T4, ws);
-
- m_curve.sqr(m_coord_x, T0, ws);
- m_coord_x.mod_sub(T1, p, sub_ws);
- m_coord_x.mod_sub(T3, p, sub_ws);
- m_coord_x.mod_sub(T3, p, sub_ws);
-
- T3.mod_sub(m_coord_x, p, sub_ws);
-
- T2 = m_coord_y;
- m_curve.mul(T2, T0, T3, ws);
- m_curve.mul(T3, m_coord_y, T1, ws);
- T2.mod_sub(T3, p, sub_ws);
- m_coord_y = T2;
-
- m_curve.mul(T3, m_coord_z, T4, ws);
- m_coord_z = T3;
- }
-
-void PointGFp::add(const word x_words[], size_t x_size,
- const word y_words[], size_t y_size,
- const word z_words[], size_t z_size,
- std::vector<BigInt>& ws_bn)
- {
- if(all_zeros(x_words, x_size) && all_zeros(z_words, z_size))
- return;
-
- if(is_zero())
- {
- m_coord_x.set_words(x_words, x_size);
- m_coord_y.set_words(y_words, y_size);
- m_coord_z.set_words(z_words, z_size);
- return;
- }
-
- resize_ws(ws_bn, m_curve.get_ws_size());
-
- secure_vector<word>& ws = ws_bn[0].get_word_vector();
- secure_vector<word>& sub_ws = ws_bn[1].get_word_vector();
-
- BigInt& T0 = ws_bn[2];
- BigInt& T1 = ws_bn[3];
- BigInt& T2 = ws_bn[4];
- BigInt& T3 = ws_bn[5];
- BigInt& T4 = ws_bn[6];
- BigInt& T5 = ws_bn[7];
-
- /*
- https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-1998-cmo-2
- */
-
- const BigInt& p = m_curve.get_p();
-
- m_curve.sqr(T0, z_words, z_size, ws); // z2^2
- m_curve.mul(T1, m_coord_x, T0, ws); // x1*z2^2
- m_curve.mul(T3, z_words, z_size, T0, ws); // z2^3
- m_curve.mul(T2, m_coord_y, T3, ws); // y1*z2^3
-
- m_curve.sqr(T3, m_coord_z, ws); // z1^2
- m_curve.mul(T4, x_words, x_size, T3, ws); // x2*z1^2
-
- m_curve.mul(T5, m_coord_z, T3, ws); // z1^3
- m_curve.mul(T0, y_words, y_size, T5, ws); // y2*z1^3
-
- T4.mod_sub(T1, p, sub_ws); // x2*z1^2 - x1*z2^2
-
- T0.mod_sub(T2, p, sub_ws);
-
- if(T4.is_zero())
- {
- if(T0.is_zero())
- {
- mult2(ws_bn);
- return;
- }
-
- // setting to zero:
- m_coord_x = 0;
- m_coord_y = m_curve.get_1_rep();
- m_coord_z = 0;
- return;
- }
-
- m_curve.sqr(T5, T4, ws);
-
- m_curve.mul(T3, T1, T5, ws);
-
- m_curve.mul(T1, T5, T4, ws);
-
- m_curve.sqr(m_coord_x, T0, ws);
- m_coord_x.mod_sub(T1, p, sub_ws);
- m_coord_x.mod_sub(T3, p, sub_ws);
- m_coord_x.mod_sub(T3, p, sub_ws);
-
- T3.mod_sub(m_coord_x, p, sub_ws);
-
- m_curve.mul(m_coord_y, T0, T3, ws);
- m_curve.mul(T3, T2, T1, ws);
-
- m_coord_y.mod_sub(T3, p, sub_ws);
-
- m_curve.mul(T3, z_words, z_size, m_coord_z, ws);
- m_curve.mul(m_coord_z, T3, T4, ws);
- }
-
-void PointGFp::mult2i(size_t iterations, std::vector<BigInt>& ws_bn)
- {
- if(iterations == 0)
- return;
-
- if(m_coord_y.is_zero())
- {
- *this = PointGFp(m_curve); // setting myself to zero
- return;
- }
-
- /*
- TODO we can save 2 squarings per iteration by computing
- a*Z^4 using values cached from previous iteration
- */
- for(size_t i = 0; i != iterations; ++i)
- mult2(ws_bn);
- }
-
-// *this *= 2
-void PointGFp::mult2(std::vector<BigInt>& ws_bn)
- {
- if(is_zero())
- return;
-
- if(m_coord_y.is_zero())
- {
- *this = PointGFp(m_curve); // setting myself to zero
- return;
- }
-
- resize_ws(ws_bn, m_curve.get_ws_size());
-
- secure_vector<word>& ws = ws_bn[0].get_word_vector();
- secure_vector<word>& sub_ws = ws_bn[1].get_word_vector();
-
- BigInt& T0 = ws_bn[2];
- BigInt& T1 = ws_bn[3];
- BigInt& T2 = ws_bn[4];
- BigInt& T3 = ws_bn[5];
- BigInt& T4 = ws_bn[6];
-
- /*
- https://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#doubling-dbl-1986-cc
- */
- const BigInt& p = m_curve.get_p();
-
- m_curve.sqr(T0, m_coord_y, ws);
-
- m_curve.mul(T1, m_coord_x, T0, ws);
- T1 <<= 2; // * 4
- m_curve.redc_mod_p(T1, sub_ws);
-
- if(m_curve.a_is_zero())
- {
- // if a == 0 then 3*x^2 + a*z^4 is just 3*x^2
- m_curve.sqr(T4, m_coord_x, ws); // x^2
- T4 *= 3; // 3*x^2
- m_curve.redc_mod_p(T4, sub_ws);
- }
- else if(m_curve.a_is_minus_3())
- {
- /*
- if a == -3 then
- 3*x^2 + a*z^4 == 3*x^2 - 3*z^4 == 3*(x^2-z^4) == 3*(x-z^2)*(x+z^2)
- */
- m_curve.sqr(T3, m_coord_z, ws); // z^2
-
- // (x-z^2)
- T2 = m_coord_x;
- T2.mod_sub(T3, p, sub_ws);
-
- // (x+z^2)
- T3.mod_add(m_coord_x, p, sub_ws);
-
- m_curve.mul(T4, T2, T3, ws); // (x-z^2)*(x+z^2)
-
- T4 *= 3; // 3*(x-z^2)*(x+z^2)
- m_curve.redc_mod_p(T4, sub_ws);
- }
- else
- {
- m_curve.sqr(T3, m_coord_z, ws); // z^2
- m_curve.sqr(T4, T3, ws); // z^4
- m_curve.mul(T3, m_curve.get_a_rep(), T4, ws); // a*z^4
-
- m_curve.sqr(T4, m_coord_x, ws); // x^2
- T4 *= 3; // 3*x^2
- T4.mod_add(T3, p, sub_ws); // 3*x^2 + a*z^4
- }
-
- m_curve.sqr(T2, T4, ws);
- T2.mod_sub(T1, p, sub_ws);
- T2.mod_sub(T1, p, sub_ws);
-
- m_curve.sqr(T3, T0, ws);
- T3 <<= 3;
- m_curve.redc_mod_p(T3, sub_ws);
-
- T1.mod_sub(T2, p, sub_ws);
-
- m_curve.mul(T0, T4, T1, ws);
- T0.mod_sub(T3, p, sub_ws);
-
- m_coord_x = T2;
-
- m_curve.mul(T2, m_coord_y, m_coord_z, ws);
- T2 <<= 1;
- m_curve.redc_mod_p(T2, sub_ws);
-
- m_coord_y = T0;
- m_coord_z = T2;
- }
-
-// arithmetic operators
-PointGFp& PointGFp::operator+=(const PointGFp& rhs)
- {
- std::vector<BigInt> ws(PointGFp::WORKSPACE_SIZE);
- add(rhs, ws);
- return *this;
- }
-
-PointGFp& PointGFp::operator-=(const PointGFp& rhs)
- {
- PointGFp minus_rhs = PointGFp(rhs).negate();
-
- if(is_zero())
- *this = minus_rhs;
- else
- *this += minus_rhs;
-
- return *this;
- }
-
-PointGFp& PointGFp::operator*=(const BigInt& scalar)
- {
- *this = scalar * *this;
- return *this;
- }
-
-PointGFp operator*(const BigInt& scalar, const PointGFp& point)
- {
- BOTAN_DEBUG_ASSERT(point.on_the_curve());
-
- const size_t scalar_bits = scalar.bits();
-
- std::vector<BigInt> ws(PointGFp::WORKSPACE_SIZE);
-
- PointGFp R[2] = { point.zero(), point };
-
- for(size_t i = scalar_bits; i > 0; i--)
- {
- const size_t b = scalar.get_bit(i - 1);
- R[b ^ 1].add(R[b], ws);
- R[b].mult2(ws);
- }
-
- if(scalar.is_negative())
- R[0].negate();
-
- BOTAN_DEBUG_ASSERT(R[0].on_the_curve());
-
- return R[0];
- }
-
-//static
-void PointGFp::force_all_affine(std::vector<PointGFp>& points,
- secure_vector<word>& ws)
- {
- if(points.size() <= 1)
- {
- for(size_t i = 0; i != points.size(); ++i)
- points[i].force_affine();
- return;
- }
-
- /*
- For >= 2 points use Montgomery's trick
-
- See Algorithm 2.26 in "Guide to Elliptic Curve Cryptography"
- (Hankerson, Menezes, Vanstone)
-
- TODO is it really necessary to save all k points in c?
- */
-
- const CurveGFp& curve = points[0].m_curve;
- const BigInt& rep_1 = curve.get_1_rep();
-
- if(ws.size() < curve.get_ws_size())
- ws.resize(curve.get_ws_size());
-
- std::vector<BigInt> c(points.size());
- c[0] = points[0].m_coord_z;
-
- for(size_t i = 1; i != points.size(); ++i)
- {
- curve.mul(c[i], c[i-1], points[i].m_coord_z, ws);
- }
-
- BigInt s_inv = curve.invert_element(c[c.size()-1], ws);
-
- BigInt z_inv, z2_inv, z3_inv;
-
- for(size_t i = points.size() - 1; i != 0; i--)
- {
- PointGFp& point = points[i];
-
- curve.mul(z_inv, s_inv, c[i-1], ws);
-
- s_inv = curve.mul_to_tmp(s_inv, point.m_coord_z, ws);
-
- curve.sqr(z2_inv, z_inv, ws);
- curve.mul(z3_inv, z2_inv, z_inv, ws);
- point.m_coord_x = curve.mul_to_tmp(point.m_coord_x, z2_inv, ws);
- point.m_coord_y = curve.mul_to_tmp(point.m_coord_y, z3_inv, ws);
- point.m_coord_z = rep_1;
- }
-
- curve.sqr(z2_inv, s_inv, ws);
- curve.mul(z3_inv, z2_inv, s_inv, ws);
- points[0].m_coord_x = curve.mul_to_tmp(points[0].m_coord_x, z2_inv, ws);
- points[0].m_coord_y = curve.mul_to_tmp(points[0].m_coord_y, z3_inv, ws);
- points[0].m_coord_z = rep_1;
- }
-
-void PointGFp::force_affine()
- {
- if(is_zero())
- throw Invalid_State("Cannot convert zero ECC point to affine");
-
- secure_vector<word> ws;
-
- const BigInt z_inv = m_curve.invert_element(m_coord_z, ws);
- const BigInt z2_inv = m_curve.sqr_to_tmp(z_inv, ws);
- const BigInt z3_inv = m_curve.mul_to_tmp(z_inv, z2_inv, ws);
- m_coord_x = m_curve.mul_to_tmp(m_coord_x, z2_inv, ws);
- m_coord_y = m_curve.mul_to_tmp(m_coord_y, z3_inv, ws);
- m_coord_z = m_curve.get_1_rep();
- }
-
-bool PointGFp::is_affine() const
- {
- return m_curve.is_one(m_coord_z);
- }
-
-BigInt PointGFp::get_affine_x() const
- {
- if(is_zero())
- throw Illegal_Transformation("Cannot convert zero point to affine");
-
- secure_vector<word> monty_ws;
-
- if(is_affine())
- return m_curve.from_rep(m_coord_x, monty_ws);
-
- BigInt z2 = m_curve.sqr_to_tmp(m_coord_z, monty_ws);
- z2 = m_curve.invert_element(z2, monty_ws);
-
- BigInt r;
- m_curve.mul(r, m_coord_x, z2, monty_ws);
- m_curve.from_rep(r, monty_ws);
- return r;
- }
-
-BigInt PointGFp::get_affine_y() const
- {
- if(is_zero())
- throw Illegal_Transformation("Cannot convert zero point to affine");
-
- secure_vector<word> monty_ws;
-
- if(is_affine())
- return m_curve.from_rep(m_coord_y, monty_ws);
-
- const BigInt z2 = m_curve.sqr_to_tmp(m_coord_z, monty_ws);
- const BigInt z3 = m_curve.mul_to_tmp(m_coord_z, z2, monty_ws);
- const BigInt z3_inv = m_curve.invert_element(z3, monty_ws);
-
- BigInt r;
- m_curve.mul(r, m_coord_y, z3_inv, monty_ws);
- m_curve.from_rep(r, monty_ws);
- return r;
- }
-
-bool PointGFp::on_the_curve() const
- {
- /*
- Is the point still on the curve?? (If everything is correct, the
- point is always on its curve; then the function will return true.
- If somehow the state is corrupted, which suggests a fault attack
- (or internal computational error), then return false.
- */
- if(is_zero())
- return true;
-
- secure_vector<word> monty_ws;
-
- const BigInt y2 = m_curve.from_rep(m_curve.sqr_to_tmp(m_coord_y, monty_ws), monty_ws);
- const BigInt x3 = m_curve.mul_to_tmp(m_coord_x, m_curve.sqr_to_tmp(m_coord_x, monty_ws), monty_ws);
- const BigInt ax = m_curve.mul_to_tmp(m_coord_x, m_curve.get_a_rep(), monty_ws);
- const BigInt z2 = m_curve.sqr_to_tmp(m_coord_z, monty_ws);
-
- if(m_coord_z == z2) // Is z equal to 1 (in Montgomery form)?
- {
- if(y2 != m_curve.from_rep(x3 + ax + m_curve.get_b_rep(), monty_ws))
- return false;
- }
-
- const BigInt z3 = m_curve.mul_to_tmp(m_coord_z, z2, monty_ws);
- const BigInt ax_z4 = m_curve.mul_to_tmp(ax, m_curve.sqr_to_tmp(z2, monty_ws), monty_ws);
- const BigInt b_z6 = m_curve.mul_to_tmp(m_curve.get_b_rep(), m_curve.sqr_to_tmp(z3, monty_ws), monty_ws);
-
- if(y2 != m_curve.from_rep(x3 + ax_z4 + b_z6, monty_ws))
- return false;
-
- return true;
- }
-
-// swaps the states of *this and other, does not throw!
-void PointGFp::swap(PointGFp& other)
- {
- m_curve.swap(other.m_curve);
- m_coord_x.swap(other.m_coord_x);
- m_coord_y.swap(other.m_coord_y);
- m_coord_z.swap(other.m_coord_z);
- }
-
-bool PointGFp::operator==(const PointGFp& other) const
- {
- if(m_curve != other.m_curve)
- return false;
-
- // If this is zero, only equal if other is also zero
- if(is_zero())
- return other.is_zero();
-
- return (get_affine_x() == other.get_affine_x() &&
- get_affine_y() == other.get_affine_y());
- }
-
-// encoding and decoding
-std::vector<uint8_t> PointGFp::encode(PointGFp::Compression_Type format) const
- {
- if(is_zero())
- return std::vector<uint8_t>(1); // single 0 byte
-
- const size_t p_bytes = m_curve.get_p().bytes();
-
- const BigInt x = get_affine_x();
- const BigInt y = get_affine_y();
-
- std::vector<uint8_t> result;
-
- if(format == PointGFp::UNCOMPRESSED)
- {
- result.resize(1 + 2*p_bytes);
- result[0] = 0x04;
- BigInt::encode_1363(&result[1], p_bytes, x);
- BigInt::encode_1363(&result[1+p_bytes], p_bytes, y);
- }
- else if(format == PointGFp::COMPRESSED)
- {
- result.resize(1 + p_bytes);
- result[0] = 0x02 | static_cast<uint8_t>(y.get_bit(0));
- BigInt::encode_1363(&result[1], p_bytes, x);
- }
- else if(format == PointGFp::HYBRID)
- {
- result.resize(1 + 2*p_bytes);
- result[0] = 0x06 | static_cast<uint8_t>(y.get_bit(0));
- BigInt::encode_1363(&result[1], p_bytes, x);
- BigInt::encode_1363(&result[1+p_bytes], p_bytes, y);
- }
- else
- throw Invalid_Argument("EC2OSP illegal point encoding");
-
- return result;
- }
-
-namespace {
-
-BigInt decompress_point(bool yMod2,
- const BigInt& x,
- const BigInt& curve_p,
- const BigInt& curve_a,
- const BigInt& curve_b)
- {
- BigInt xpow3 = x * x * x;
-
- BigInt g = curve_a * x;
- g += xpow3;
- g += curve_b;
- g = g % curve_p;
-
- BigInt z = ressol(g, curve_p);
-
- if(z < 0)
- throw Illegal_Point("error during EC point decompression");
-
- if(z.get_bit(0) != yMod2)
- z = curve_p - z;
-
- return z;
- }
-
-}
-
-PointGFp OS2ECP(const uint8_t data[], size_t data_len,
- const CurveGFp& curve)
- {
- // Should we really be doing this?
- if(data_len <= 1)
- return PointGFp(curve); // return zero
-
- std::pair<BigInt, BigInt> xy = OS2ECP(data, data_len, curve.get_p(), curve.get_a(), curve.get_b());
-
- PointGFp point(curve, xy.first, xy.second);
-
- if(!point.on_the_curve())
- throw Illegal_Point("OS2ECP: Decoded point was not on the curve");
-
- return point;
- }
-
-std::pair<BigInt, BigInt> OS2ECP(const uint8_t data[], size_t data_len,
- const BigInt& curve_p,
- const BigInt& curve_a,
- const BigInt& curve_b)
- {
- if(data_len <= 1)
- throw Decoding_Error("OS2ECP invalid point");
-
- const uint8_t pc = data[0];
-
- BigInt x, y;
-
- if(pc == 2 || pc == 3)
- {
- //compressed form
- x = BigInt::decode(&data[1], data_len - 1);
-
- const bool y_mod_2 = ((pc & 0x01) == 1);
- y = decompress_point(y_mod_2, x, curve_p, curve_a, curve_b);
- }
- else if(pc == 4)
- {
- const size_t l = (data_len - 1) / 2;
-
- // uncompressed form
- x = BigInt::decode(&data[1], l);
- y = BigInt::decode(&data[l+1], l);
- }
- else if(pc == 6 || pc == 7)
- {
- const size_t l = (data_len - 1) / 2;
-
- // hybrid form
- x = BigInt::decode(&data[1], l);
- y = BigInt::decode(&data[l+1], l);
-
- const bool y_mod_2 = ((pc & 0x01) == 1);
-
- if(decompress_point(y_mod_2, x, curve_p, curve_a, curve_b) != y)
- throw Illegal_Point("OS2ECP: Decoding error in hybrid format");
- }
- else
- throw Invalid_Argument("OS2ECP: Unknown format type " + std::to_string(pc));
-
- return std::make_pair(x, y);
- }
-
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-28 13:45:33 +0000