1 files changed, 403 insertions, 0 deletions
diff --git a/src/libs/3rdparty/botan/src/lib/math/mp/mp_karat.cpp b/src/libs/3rdparty/botan/src/lib/math/mp/mp_karat.cpp
new file mode 100644
index 00000000000..69e2ae6656d
--- /dev/null
+++ b/src/libs/3rdparty/botan/src/lib/math/mp/mp_karat.cpp
@@ -0,0 +1,403 @@
+/*
+* Multiplication and Squaring
+* (C) 1999-2010,2018 Jack Lloyd
+*     2016 Matthias Gierlings
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/internal/mp_core.h>
+#include <botan/internal/mp_asmi.h>
+#include <botan/internal/ct_utils.h>
+#include <botan/mem_ops.h>
+#include <botan/exceptn.h>
+
+namespace Botan {
+
+namespace {
+
+const size_t KARATSUBA_MULTIPLY_THRESHOLD = 32;
+const size_t KARATSUBA_SQUARE_THRESHOLD = 32;
+
+/*
+* Simple O(N^2) Multiplication
+*/
+void basecase_mul(word z[], size_t z_size,
+                  const word x[], size_t x_size,
+                  const word y[], size_t y_size)
+   {
+   if(z_size < x_size + y_size)
+      throw Invalid_Argument("basecase_mul z_size too small");
+
+   const size_t x_size_8 = x_size - (x_size % 8);
+
+   clear_mem(z, z_size);
+
+   for(size_t i = 0; i != y_size; ++i)
+      {
+      const word y_i = y[i];
+
+      word carry = 0;
+
+      for(size_t j = 0; j != x_size_8; j += 8)
+         carry = word8_madd3(z + i + j, x + j, y_i, carry);
+
+      for(size_t j = x_size_8; j != x_size; ++j)
+         z[i+j] = word_madd3(x[j], y_i, z[i+j], &carry);
+
+      z[x_size+i] = carry;
+      }
+   }
+
+void basecase_sqr(word z[], size_t z_size,
+                  const word x[], size_t x_size)
+   {
+   if(z_size < 2*x_size)
+      throw Invalid_Argument("basecase_sqr z_size too small");
+
+   const size_t x_size_8 = x_size - (x_size % 8);
+
+   clear_mem(z, z_size);
+
+   for(size_t i = 0; i != x_size; ++i)
+      {
+      const word x_i = x[i];
+
+      word carry = 0;
+
+      for(size_t j = 0; j != x_size_8; j += 8)
+         carry = word8_madd3(z + i + j, x + j, x_i, carry);
+
+      for(size_t j = x_size_8; j != x_size; ++j)
+         z[i+j] = word_madd3(x[j], x_i, z[i+j], &carry);
+
+      z[x_size+i] = carry;
+      }
+   }
+
+/*
+* Karatsuba Multiplication Operation
+*/
+void karatsuba_mul(word z[], const word x[], const word y[], size_t N,
+                   word workspace[])
+   {
+   if(N < KARATSUBA_MULTIPLY_THRESHOLD || N % 2)
+      {
+      if(N == 6)
+         return bigint_comba_mul6(z, x, y);
+      else if(N == 8)
+         return bigint_comba_mul8(z, x, y);
+      else if(N == 9)
+         return bigint_comba_mul9(z, x, y);
+      else if(N == 16)
+         return bigint_comba_mul16(z, x, y);
+      else if(N == 24)
+         return bigint_comba_mul24(z, x, y);
+      else
+         return basecase_mul(z, 2*N, x, N, y, N);
+      }
+
+   const size_t N2 = N / 2;
+
+   const word* x0 = x;
+   const word* x1 = x + N2;
+   const word* y0 = y;
+   const word* y1 = y + N2;
+   word* z0 = z;
+   word* z1 = z + N;
+
+   word* ws0 = workspace;
+   word* ws1 = workspace + N;
+
+   clear_mem(workspace, 2*N);
+
+   /*
+   * If either of cmp0 or cmp1 is zero then z0 or z1 resp is zero here,
+   * resulting in a no-op - z0*z1 will be equal to zero so we don't need to do
+   * anything, clear_mem above already set the correct result.
+   *
+   * However we ignore the result of the comparisons and always perform the
+   * subtractions and recursively multiply to avoid the timing channel.
+   */
+
+   // First compute (X_lo - X_hi)*(Y_hi - Y_lo)
+   const word cmp0 = bigint_sub_abs(z0, x0, x1, N2, workspace);
+   const word cmp1 = bigint_sub_abs(z1, y1, y0, N2, workspace);
+
+   karatsuba_mul(ws0, z0, z1, N2, ws1);
+
+   // Compute X_lo * Y_lo
+   karatsuba_mul(z0, x0, y0, N2, ws1);
+
+   // Compute X_hi * Y_hi
+   karatsuba_mul(z1, x1, y1, N2, ws1);
+
+   const word ws_carry = bigint_add3_nc(ws1, z0, N, z1, N);
+   word z_carry = bigint_add2_nc(z + N2, N, ws1, N);
+
+   z_carry += bigint_add2_nc(z + N + N2, N2, &ws_carry, 1);
+   bigint_add2_nc(z + N + N2, N2, &z_carry, 1);
+
+   clear_mem(workspace + N, N2);
+
+   const word neg_mask = CT::is_equal<word>(cmp0, cmp1);
+
+   bigint_cnd_addsub(neg_mask, z + N2, workspace, 2*N-N2);
+   }
+
+/*
+* Karatsuba Squaring Operation
+*/
+void karatsuba_sqr(word z[], const word x[], size_t N, word workspace[])
+   {
+   if(N < KARATSUBA_SQUARE_THRESHOLD || N % 2)
+      {
+      if(N == 6)
+         return bigint_comba_sqr6(z, x);
+      else if(N == 8)
+         return bigint_comba_sqr8(z, x);
+      else if(N == 9)
+         return bigint_comba_sqr9(z, x);
+      else if(N == 16)
+         return bigint_comba_sqr16(z, x);
+      else if(N == 24)
+         return bigint_comba_sqr24(z, x);
+      else
+         return basecase_sqr(z, 2*N, x, N);
+      }
+
+   const size_t N2 = N / 2;
+
+   const word* x0 = x;
+   const word* x1 = x + N2;
+   word* z0 = z;
+   word* z1 = z + N;
+
+   word* ws0 = workspace;
+   word* ws1 = workspace + N;
+
+   clear_mem(workspace, 2*N);
+
+   // See comment in karatsuba_mul
+   bigint_sub_abs(z0, x0, x1, N2, workspace);
+   karatsuba_sqr(ws0, z0, N2, ws1);
+
+   karatsuba_sqr(z0, x0, N2, ws1);
+   karatsuba_sqr(z1, x1, N2, ws1);
+
+   const word ws_carry = bigint_add3_nc(ws1, z0, N, z1, N);
+   word z_carry = bigint_add2_nc(z + N2, N, ws1, N);
+
+   z_carry += bigint_add2_nc(z + N + N2, N2, &ws_carry, 1);
+   bigint_add2_nc(z + N + N2, N2, &z_carry, 1);
+
+   /*
+   * This is only actually required if cmp (result of bigint_sub_abs) is != 0,
+   * however if cmp==0 then ws0[0:N] == 0 and avoiding the jump hides a
+   * timing channel.
+   */
+   bigint_sub2(z + N2, 2*N-N2, ws0, N);
+   }
+
+/*
+* Pick a good size for the Karatsuba multiply
+*/
+size_t karatsuba_size(size_t z_size,
+                      size_t x_size, size_t x_sw,
+                      size_t y_size, size_t y_sw)
+   {
+   if(x_sw > x_size || x_sw > y_size || y_sw > x_size || y_sw > y_size)
+      return 0;
+
+   if(((x_size == x_sw) && (x_size % 2)) ||
+      ((y_size == y_sw) && (y_size % 2)))
+      return 0;
+
+   const size_t start = (x_sw > y_sw) ? x_sw : y_sw;
+   const size_t end = (x_size < y_size) ? x_size : y_size;
+
+   if(start == end)
+      {
+      if(start % 2)
+         return 0;
+      return start;
+      }
+
+   for(size_t j = start; j <= end; ++j)
+      {
+      if(j % 2)
+         continue;
+
+      if(2*j > z_size)
+         return 0;
+
+      if(x_sw <= j && j <= x_size && y_sw <= j && j <= y_size)
+         {
+         if(j % 4 == 2 &&
+            (j+2) <= x_size && (j+2) <= y_size && 2*(j+2) <= z_size)
+            return j+2;
+         return j;
+         }
+      }
+
+   return 0;
+   }
+
+/*
+* Pick a good size for the Karatsuba squaring
+*/
+size_t karatsuba_size(size_t z_size, size_t x_size, size_t x_sw)
+   {
+   if(x_sw == x_size)
+      {
+      if(x_sw % 2)
+         return 0;
+      return x_sw;
+      }
+
+   for(size_t j = x_sw; j <= x_size; ++j)
+      {
+      if(j % 2)
+         continue;
+
+      if(2*j > z_size)
+         return 0;
+
+      if(j % 4 == 2 && (j+2) <= x_size && 2*(j+2) <= z_size)
+         return j+2;
+      return j;
+      }
+
+   return 0;
+   }
+
+template<size_t SZ>
+inline bool sized_for_comba_mul(size_t x_sw, size_t x_size,
+                                size_t y_sw, size_t y_size,
+                                size_t z_size)
+   {
+   return (x_sw <= SZ && x_size >= SZ &&
+           y_sw <= SZ && y_size >= SZ &&
+           z_size >= 2*SZ);
+   }
+
+template<size_t SZ>
+inline bool sized_for_comba_sqr(size_t x_sw, size_t x_size,
+                                size_t z_size)
+   {
+   return (x_sw <= SZ && x_size >= SZ && z_size >= 2*SZ);
+   }
+
+}
+
+void bigint_mul(word z[], size_t z_size,
+                const word x[], size_t x_size, size_t x_sw,
+                const word y[], size_t y_size, size_t y_sw,
+                word workspace[], size_t ws_size)
+   {
+   clear_mem(z, z_size);
+
+   if(x_sw == 1)
+      {
+      bigint_linmul3(z, y, y_sw, x[0]);
+      }
+   else if(y_sw == 1)
+      {
+      bigint_linmul3(z, x, x_sw, y[0]);
+      }
+   else if(sized_for_comba_mul<4>(x_sw, x_size, y_sw, y_size, z_size))
+      {
+      bigint_comba_mul4(z, x, y);
+      }
+   else if(sized_for_comba_mul<6>(x_sw, x_size, y_sw, y_size, z_size))
+      {
+      bigint_comba_mul6(z, x, y);
+      }
+   else if(sized_for_comba_mul<8>(x_sw, x_size, y_sw, y_size, z_size))
+      {
+      bigint_comba_mul8(z, x, y);
+      }
+   else if(sized_for_comba_mul<9>(x_sw, x_size, y_sw, y_size, z_size))
+      {
+      bigint_comba_mul9(z, x, y);
+      }
+   else if(sized_for_comba_mul<16>(x_sw, x_size, y_sw, y_size, z_size))
+      {
+      bigint_comba_mul16(z, x, y);
+      }
+   else if(sized_for_comba_mul<24>(x_sw, x_size, y_sw, y_size, z_size))
+      {
+      bigint_comba_mul24(z, x, y);
+      }
+   else if(x_sw < KARATSUBA_MULTIPLY_THRESHOLD ||
+           y_sw < KARATSUBA_MULTIPLY_THRESHOLD ||
+           !workspace)
+      {
+      basecase_mul(z, z_size, x, x_sw, y, y_sw);
+      }
+   else
+      {
+      const size_t N = karatsuba_size(z_size, x_size, x_sw, y_size, y_sw);
+
+      if(N && z_size >= 2*N && ws_size >= 2*N)
+         karatsuba_mul(z, x, y, N, workspace);
+      else
+         basecase_mul(z, z_size, x, x_sw, y, y_sw);
+      }
+   }
+
+/*
+* Squaring Algorithm Dispatcher
+*/
+void bigint_sqr(word z[], size_t z_size,
+                const word x[], size_t x_size, size_t x_sw,
+                word workspace[], size_t ws_size)
+   {
+   clear_mem(z, z_size);
+
+   BOTAN_ASSERT(z_size/2 >= x_sw, "Output size is sufficient");
+
+   if(x_sw == 1)
+      {
+      bigint_linmul3(z, x, x_sw, x[0]);
+      }
+   else if(sized_for_comba_sqr<4>(x_sw, x_size, z_size))
+      {
+      bigint_comba_sqr4(z, x);
+      }
+   else if(sized_for_comba_sqr<6>(x_sw, x_size, z_size))
+      {
+      bigint_comba_sqr6(z, x);
+      }
+   else if(sized_for_comba_sqr<8>(x_sw, x_size, z_size))
+      {
+      bigint_comba_sqr8(z, x);
+      }
+   else if(sized_for_comba_sqr<9>(x_sw, x_size, z_size))
+      {
+      bigint_comba_sqr9(z, x);
+      }
+   else if(sized_for_comba_sqr<16>(x_sw, x_size, z_size))
+      {
+      bigint_comba_sqr16(z, x);
+      }
+   else if(sized_for_comba_sqr<24>(x_sw, x_size, z_size))
+      {
+      bigint_comba_sqr24(z, x);
+      }
+   else if(x_size < KARATSUBA_SQUARE_THRESHOLD || !workspace)
+      {
+      basecase_sqr(z, z_size, x, x_sw);
+      }
+   else
+      {
+      const size_t N = karatsuba_size(z_size, x_size, x_sw);
+
+      if(N && z_size >= 2*N && ws_size >= 2*N)
+         karatsuba_sqr(z, x, N, workspace);
+      else
+         basecase_sqr(z, z_size, x, x_sw);
+      }
+   }
+
+}