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diff --git a/comm/third_party/botan/src/lib/math/mp/mp_core.h b/comm/third_party/botan/src/lib/math/mp/mp_core.h
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+++ b/comm/third_party/botan/src/lib/math/mp/mp_core.h
@@ -0,0 +1,819 @@
+/*
+* MPI Algorithms
+* (C) 1999-2010,2018 Jack Lloyd
+* 2006 Luca Piccarreta
+* 2016 Matthias Gierlings
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_MP_CORE_OPS_H_
+#define BOTAN_MP_CORE_OPS_H_
+
+#include <botan/types.h>
+#include <botan/exceptn.h>
+#include <botan/mem_ops.h>
+#include <botan/internal/mp_asmi.h>
+#include <botan/internal/ct_utils.h>
+#include <algorithm>
+
+namespace Botan {
+
+const word MP_WORD_MAX = ~static_cast<word>(0);
+
+/*
+* If cond == 0, does nothing.
+* If cond > 0, swaps x[0:size] with y[0:size]
+* Runs in constant time
+*/
+inline void bigint_cnd_swap(word cnd, word x[], word y[], size_t size)
+ {
+ const auto mask = CT::Mask<word>::expand(cnd);
+
+ for(size_t i = 0; i != size; ++i)
+ {
+ const word a = x[i];
+ const word b = y[i];
+ x[i] = mask.select(b, a);
+ y[i] = mask.select(a, b);
+ }
+ }
+
+inline word bigint_cnd_add(word cnd, word x[], word x_size,
+ const word y[], size_t y_size)
+ {
+ BOTAN_ASSERT(x_size >= y_size, "Expected sizes");
+
+ const auto mask = CT::Mask<word>::expand(cnd);
+
+ word carry = 0;
+
+ const size_t blocks = y_size - (y_size % 8);
+ word z[8] = { 0 };
+
+ for(size_t i = 0; i != blocks; i += 8)
+ {
+ carry = word8_add3(z, x + i, y + i, carry);
+ mask.select_n(x + i, z, x + i, 8);
+ }
+
+ for(size_t i = blocks; i != y_size; ++i)
+ {
+ z[0] = word_add(x[i], y[i], &carry);
+ x[i] = mask.select(z[0], x[i]);
+ }
+
+ for(size_t i = y_size; i != x_size; ++i)
+ {
+ z[0] = word_add(x[i], 0, &carry);
+ x[i] = mask.select(z[0], x[i]);
+ }
+
+ return mask.if_set_return(carry);
+ }
+
+/*
+* If cond > 0 adds x[0:size] and y[0:size] and returns carry
+* Runs in constant time
+*/
+inline word bigint_cnd_add(word cnd, word x[], const word y[], size_t size)
+ {
+ return bigint_cnd_add(cnd, x, size, y, size);
+ }
+
+/*
+* If cond > 0 subtracts x[0:size] and y[0:size] and returns borrow
+* Runs in constant time
+*/
+inline word bigint_cnd_sub(word cnd,
+ word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ BOTAN_ASSERT(x_size >= y_size, "Expected sizes");
+
+ const auto mask = CT::Mask<word>::expand(cnd);
+
+ word carry = 0;
+
+ const size_t blocks = y_size - (y_size % 8);
+ word z[8] = { 0 };
+
+ for(size_t i = 0; i != blocks; i += 8)
+ {
+ carry = word8_sub3(z, x + i, y + i, carry);
+ mask.select_n(x + i, z, x + i, 8);
+ }
+
+ for(size_t i = blocks; i != y_size; ++i)
+ {
+ z[0] = word_sub(x[i], y[i], &carry);
+ x[i] = mask.select(z[0], x[i]);
+ }
+
+ for(size_t i = y_size; i != x_size; ++i)
+ {
+ z[0] = word_sub(x[i], 0, &carry);
+ x[i] = mask.select(z[0], x[i]);
+ }
+
+ return mask.if_set_return(carry);
+ }
+
+/*
+* If cond > 0 adds x[0:size] and y[0:size] and returns carry
+* Runs in constant time
+*/
+inline word bigint_cnd_sub(word cnd, word x[], const word y[], size_t size)
+ {
+ return bigint_cnd_sub(cnd, x, size, y, size);
+ }
+
+
+/*
+* Equivalent to
+* bigint_cnd_add( mask, x, y, size);
+* bigint_cnd_sub(~mask, x, y, size);
+*
+* Mask must be either 0 or all 1 bits
+*/
+inline void bigint_cnd_add_or_sub(CT::Mask<word> mask, word x[], const word y[], size_t size)
+ {
+ const size_t blocks = size - (size % 8);
+
+ word carry = 0;
+ word borrow = 0;
+
+ word t0[8] = { 0 };
+ word t1[8] = { 0 };
+
+ for(size_t i = 0; i != blocks; i += 8)
+ {
+ carry = word8_add3(t0, x + i, y + i, carry);
+ borrow = word8_sub3(t1, x + i, y + i, borrow);
+
+ for(size_t j = 0; j != 8; ++j)
+ x[i+j] = mask.select(t0[j], t1[j]);
+ }
+
+ for(size_t i = blocks; i != size; ++i)
+ {
+ const word a = word_add(x[i], y[i], &carry);
+ const word s = word_sub(x[i], y[i], &borrow);
+
+ x[i] = mask.select(a, s);
+ }
+ }
+
+/*
+* Equivalent to
+* bigint_cnd_add( mask, x, size, y, size);
+* bigint_cnd_sub(~mask, x, size, z, size);
+*
+* Mask must be either 0 or all 1 bits
+*
+* Returns the carry or borrow resp
+*/
+inline word bigint_cnd_addsub(CT::Mask<word> mask, word x[],
+ const word y[], const word z[],
+ size_t size)
+ {
+ const size_t blocks = size - (size % 8);
+
+ word carry = 0;
+ word borrow = 0;
+
+ word t0[8] = { 0 };
+ word t1[8] = { 0 };
+
+ for(size_t i = 0; i != blocks; i += 8)
+ {
+ carry = word8_add3(t0, x + i, y + i, carry);
+ borrow = word8_sub3(t1, x + i, z + i, borrow);
+
+ for(size_t j = 0; j != 8; ++j)
+ x[i+j] = mask.select(t0[j], t1[j]);
+ }
+
+ for(size_t i = blocks; i != size; ++i)
+ {
+ t0[0] = word_add(x[i], y[i], &carry);
+ t1[0] = word_sub(x[i], z[i], &borrow);
+ x[i] = mask.select(t0[0], t1[0]);
+ }
+
+ return mask.select(carry, borrow);
+ }
+
+/*
+* 2s complement absolute value
+* If cond > 0 sets x to ~x + 1
+* Runs in constant time
+*/
+inline void bigint_cnd_abs(word cnd, word x[], size_t size)
+ {
+ const auto mask = CT::Mask<word>::expand(cnd);
+
+ word carry = mask.if_set_return(1);
+ for(size_t i = 0; i != size; ++i)
+ {
+ const word z = word_add(~x[i], 0, &carry);
+ x[i] = mask.select(z, x[i]);
+ }
+ }
+
+/**
+* Two operand addition with carry out
+*/
+inline word bigint_add2_nc(word x[], size_t x_size, const word y[], size_t y_size)
+ {
+ word carry = 0;
+
+ BOTAN_ASSERT(x_size >= y_size, "Expected sizes");
+
+ const size_t blocks = y_size - (y_size % 8);
+
+ for(size_t i = 0; i != blocks; i += 8)
+ carry = word8_add2(x + i, y + i, carry);
+
+ for(size_t i = blocks; i != y_size; ++i)
+ x[i] = word_add(x[i], y[i], &carry);
+
+ for(size_t i = y_size; i != x_size; ++i)
+ x[i] = word_add(x[i], 0, &carry);
+
+ return carry;
+ }
+
+/**
+* Three operand addition with carry out
+*/
+inline word bigint_add3_nc(word z[],
+ const word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ if(x_size < y_size)
+ { return bigint_add3_nc(z, y, y_size, x, x_size); }
+
+ word carry = 0;
+
+ const size_t blocks = y_size - (y_size % 8);
+
+ for(size_t i = 0; i != blocks; i += 8)
+ carry = word8_add3(z + i, x + i, y + i, carry);
+
+ for(size_t i = blocks; i != y_size; ++i)
+ z[i] = word_add(x[i], y[i], &carry);
+
+ for(size_t i = y_size; i != x_size; ++i)
+ z[i] = word_add(x[i], 0, &carry);
+
+ return carry;
+ }
+
+/**
+* Two operand addition
+* @param x the first operand (and output)
+* @param x_size size of x
+* @param y the second operand
+* @param y_size size of y (must be >= x_size)
+*/
+inline void bigint_add2(word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ x[x_size] += bigint_add2_nc(x, x_size, y, y_size);
+ }
+
+/**
+* Three operand addition
+*/
+inline void bigint_add3(word z[],
+ const word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ z[x_size > y_size ? x_size : y_size] +=
+ bigint_add3_nc(z, x, x_size, y, y_size);
+ }
+
+/**
+* Two operand subtraction
+*/
+inline word bigint_sub2(word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ word borrow = 0;
+
+ BOTAN_ASSERT(x_size >= y_size, "Expected sizes");
+
+ const size_t blocks = y_size - (y_size % 8);
+
+ for(size_t i = 0; i != blocks; i += 8)
+ borrow = word8_sub2(x + i, y + i, borrow);
+
+ for(size_t i = blocks; i != y_size; ++i)
+ x[i] = word_sub(x[i], y[i], &borrow);
+
+ for(size_t i = y_size; i != x_size; ++i)
+ x[i] = word_sub(x[i], 0, &borrow);
+
+ return borrow;
+ }
+
+/**
+* Two operand subtraction, x = y - x; assumes y >= x
+*/
+inline void bigint_sub2_rev(word x[], const word y[], size_t y_size)
+ {
+ word borrow = 0;
+
+ const size_t blocks = y_size - (y_size % 8);
+
+ for(size_t i = 0; i != blocks; i += 8)
+ borrow = word8_sub2_rev(x + i, y + i, borrow);
+
+ for(size_t i = blocks; i != y_size; ++i)
+ x[i] = word_sub(y[i], x[i], &borrow);
+
+ BOTAN_ASSERT(borrow == 0, "y must be greater than x");
+ }
+
+/**
+* Three operand subtraction
+*/
+inline word bigint_sub3(word z[],
+ const word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ word borrow = 0;
+
+ BOTAN_ASSERT(x_size >= y_size, "Expected sizes");
+
+ const size_t blocks = y_size - (y_size % 8);
+
+ for(size_t i = 0; i != blocks; i += 8)
+ borrow = word8_sub3(z + i, x + i, y + i, borrow);
+
+ for(size_t i = blocks; i != y_size; ++i)
+ z[i] = word_sub(x[i], y[i], &borrow);
+
+ for(size_t i = y_size; i != x_size; ++i)
+ z[i] = word_sub(x[i], 0, &borrow);
+
+ return borrow;
+ }
+
+/**
+* Return abs(x-y), ie if x >= y, then compute z = x - y
+* Otherwise compute z = y - x
+* No borrow is possible since the result is always >= 0
+*
+* Returns ~0 if x >= y or 0 if x < y
+* @param z output array of at least N words
+* @param x input array of N words
+* @param y input array of N words
+* @param N length of x and y
+* @param ws array of at least 2*N words
+*/
+inline CT::Mask<word>
+bigint_sub_abs(word z[],
+ const word x[], const word y[], size_t N,
+ word ws[])
+ {
+ // Subtract in both direction then conditional copy out the result
+
+ word* ws0 = ws;
+ word* ws1 = ws + N;
+
+ word borrow0 = 0;
+ word borrow1 = 0;
+
+ const size_t blocks = N - (N % 8);
+
+ for(size_t i = 0; i != blocks; i += 8)
+ {
+ borrow0 = word8_sub3(ws0 + i, x + i, y + i, borrow0);
+ borrow1 = word8_sub3(ws1 + i, y + i, x + i, borrow1);
+ }
+
+ for(size_t i = blocks; i != N; ++i)
+ {
+ ws0[i] = word_sub(x[i], y[i], &borrow0);
+ ws1[i] = word_sub(y[i], x[i], &borrow1);
+ }
+
+ return CT::conditional_copy_mem(borrow0, z, ws1, ws0, N);
+ }
+
+/*
+* Shift Operations
+*/
+inline void bigint_shl1(word x[], size_t x_size, size_t x_words,
+ size_t word_shift, size_t bit_shift)
+ {
+ copy_mem(x + word_shift, x, x_words);
+ clear_mem(x, word_shift);
+
+ const auto carry_mask = CT::Mask<word>::expand(bit_shift);
+ const size_t carry_shift = carry_mask.if_set_return(BOTAN_MP_WORD_BITS - bit_shift);
+
+ word carry = 0;
+ for(size_t i = word_shift; i != x_size; ++i)
+ {
+ const word w = x[i];
+ x[i] = (w << bit_shift) | carry;
+ carry = carry_mask.if_set_return(w >> carry_shift);
+ }
+ }
+
+inline void bigint_shr1(word x[], size_t x_size,
+ size_t word_shift, size_t bit_shift)
+ {
+ const size_t top = x_size >= word_shift ? (x_size - word_shift) : 0;
+
+ if(top > 0)
+ copy_mem(x, x + word_shift, top);
+ clear_mem(x + top, std::min(word_shift, x_size));
+
+ const auto carry_mask = CT::Mask<word>::expand(bit_shift);
+ const size_t carry_shift = carry_mask.if_set_return(BOTAN_MP_WORD_BITS - bit_shift);
+
+ word carry = 0;
+
+ for(size_t i = 0; i != top; ++i)
+ {
+ const word w = x[top - i - 1];
+ x[top-i-1] = (w >> bit_shift) | carry;
+ carry = carry_mask.if_set_return(w << carry_shift);
+ }
+ }
+
+inline void bigint_shl2(word y[], const word x[], size_t x_size,
+ size_t word_shift, size_t bit_shift)
+ {
+ copy_mem(y + word_shift, x, x_size);
+
+ const auto carry_mask = CT::Mask<word>::expand(bit_shift);
+ const size_t carry_shift = carry_mask.if_set_return(BOTAN_MP_WORD_BITS - bit_shift);
+
+ word carry = 0;
+ for(size_t i = word_shift; i != x_size + word_shift + 1; ++i)
+ {
+ const word w = y[i];
+ y[i] = (w << bit_shift) | carry;
+ carry = carry_mask.if_set_return(w >> carry_shift);
+ }
+ }
+
+inline void bigint_shr2(word y[], const word x[], size_t x_size,
+ size_t word_shift, size_t bit_shift)
+ {
+ const size_t new_size = x_size < word_shift ? 0 : (x_size - word_shift);
+
+ if(new_size > 0)
+ copy_mem(y, x + word_shift, new_size);
+
+ const auto carry_mask = CT::Mask<word>::expand(bit_shift);
+ const size_t carry_shift = carry_mask.if_set_return(BOTAN_MP_WORD_BITS - bit_shift);
+
+ word carry = 0;
+ for(size_t i = new_size; i > 0; --i)
+ {
+ word w = y[i-1];
+ y[i-1] = (w >> bit_shift) | carry;
+ carry = carry_mask.if_set_return(w << carry_shift);
+ }
+ }
+
+/*
+* Linear Multiply - returns the carry
+*/
+inline word BOTAN_WARN_UNUSED_RESULT bigint_linmul2(word x[], size_t x_size, word y)
+ {
+ const size_t blocks = x_size - (x_size % 8);
+
+ word carry = 0;
+
+ for(size_t i = 0; i != blocks; i += 8)
+ carry = word8_linmul2(x + i, y, carry);
+
+ for(size_t i = blocks; i != x_size; ++i)
+ x[i] = word_madd2(x[i], y, &carry);
+
+ return carry;
+ }
+
+inline void bigint_linmul3(word z[], const word x[], size_t x_size, word y)
+ {
+ const size_t blocks = x_size - (x_size % 8);
+
+ word carry = 0;
+
+ for(size_t i = 0; i != blocks; i += 8)
+ carry = word8_linmul3(z + i, x + i, y, carry);
+
+ for(size_t i = blocks; i != x_size; ++i)
+ z[i] = word_madd2(x[i], y, &carry);
+
+ z[x_size] = carry;
+ }
+
+/**
+* Compare x and y
+* Return -1 if x < y
+* Return 0 if x == y
+* Return 1 if x > y
+*/
+inline int32_t bigint_cmp(const word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ static_assert(sizeof(word) >= sizeof(uint32_t), "Size assumption");
+
+ const word LT = static_cast<word>(-1);
+ const word EQ = 0;
+ const word GT = 1;
+
+ const size_t common_elems = std::min(x_size, y_size);
+
+ word result = EQ; // until found otherwise
+
+ for(size_t i = 0; i != common_elems; i++)
+ {
+ const auto is_eq = CT::Mask<word>::is_equal(x[i], y[i]);
+ const auto is_lt = CT::Mask<word>::is_lt(x[i], y[i]);
+
+ result = is_eq.select(result, is_lt.select(LT, GT));
+ }
+
+ if(x_size < y_size)
+ {
+ word mask = 0;
+ for(size_t i = x_size; i != y_size; i++)
+ mask |= y[i];
+
+ // If any bits were set in high part of y, then x < y
+ result = CT::Mask<word>::is_zero(mask).select(result, LT);
+ }
+ else if(y_size < x_size)
+ {
+ word mask = 0;
+ for(size_t i = y_size; i != x_size; i++)
+ mask |= x[i];
+
+ // If any bits were set in high part of x, then x > y
+ result = CT::Mask<word>::is_zero(mask).select(result, GT);
+ }
+
+ CT::unpoison(result);
+ BOTAN_DEBUG_ASSERT(result == LT || result == GT || result == EQ);
+ return static_cast<int32_t>(result);
+ }
+
+/**
+* Compare x and y
+* Return ~0 if x[0:x_size] < y[0:y_size] or 0 otherwise
+* If lt_or_equal is true, returns ~0 also for x == y
+*/
+inline CT::Mask<word>
+bigint_ct_is_lt(const word x[], size_t x_size,
+ const word y[], size_t y_size,
+ bool lt_or_equal = false)
+ {
+ const size_t common_elems = std::min(x_size, y_size);
+
+ auto is_lt = CT::Mask<word>::expand(lt_or_equal);
+
+ for(size_t i = 0; i != common_elems; i++)
+ {
+ const auto eq = CT::Mask<word>::is_equal(x[i], y[i]);
+ const auto lt = CT::Mask<word>::is_lt(x[i], y[i]);
+ is_lt = eq.select_mask(is_lt, lt);
+ }
+
+ if(x_size < y_size)
+ {
+ word mask = 0;
+ for(size_t i = x_size; i != y_size; i++)
+ mask |= y[i];
+ // If any bits were set in high part of y, then is_lt should be forced true
+ is_lt |= CT::Mask<word>::expand(mask);
+ }
+ else if(y_size < x_size)
+ {
+ word mask = 0;
+ for(size_t i = y_size; i != x_size; i++)
+ mask |= x[i];
+
+ // If any bits were set in high part of x, then is_lt should be false
+ is_lt &= CT::Mask<word>::is_zero(mask);
+ }
+
+ return is_lt;
+ }
+
+inline CT::Mask<word>
+bigint_ct_is_eq(const word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ const size_t common_elems = std::min(x_size, y_size);
+
+ word diff = 0;
+
+ for(size_t i = 0; i != common_elems; i++)
+ {
+ diff |= (x[i] ^ y[i]);
+ }
+
+ // If any bits were set in high part of x/y, then they are not equal
+ if(x_size < y_size)
+ {
+ for(size_t i = x_size; i != y_size; i++)
+ diff |= y[i];
+ }
+ else if(y_size < x_size)
+ {
+ for(size_t i = y_size; i != x_size; i++)
+ diff |= x[i];
+ }
+
+ return CT::Mask<word>::is_zero(diff);
+ }
+
+/**
+* Set z to abs(x-y), ie if x >= y, then compute z = x - y
+* Otherwise compute z = y - x
+* No borrow is possible since the result is always >= 0
+*
+* Return the relative size of x vs y (-1, 0, 1)
+*
+* @param z output array of max(x_size,y_size) words
+* @param x input param
+* @param x_size length of x
+* @param y input param
+* @param y_size length of y
+*/
+inline int32_t
+bigint_sub_abs(word z[],
+ const word x[], size_t x_size,
+ const word y[], size_t y_size)
+ {
+ const int32_t relative_size = bigint_cmp(x, x_size, y, y_size);
+
+ // Swap if relative_size == -1
+ const bool need_swap = relative_size < 0;
+ CT::conditional_swap_ptr(need_swap, x, y);
+ CT::conditional_swap(need_swap, x_size, y_size);
+
+ /*
+ * We know at this point that x >= y so if y_size is larger than
+ * x_size, we are guaranteed they are just leading zeros which can
+ * be ignored
+ */
+ y_size = std::min(x_size, y_size);
+
+ bigint_sub3(z, x, x_size, y, y_size);
+
+ return relative_size;
+ }
+
+/**
+* Set t to t-s modulo mod
+*
+* @param t first integer
+* @param s second integer
+* @param mod the modulus
+* @param mod_sw size of t, s, and mod
+* @param ws workspace of size mod_sw
+*/
+inline void
+bigint_mod_sub(word t[], const word s[], const word mod[], size_t mod_sw, word ws[])
+ {
+ // is t < s or not?
+ const auto is_lt = bigint_ct_is_lt(t, mod_sw, s, mod_sw);
+
+ // ws = p - s
+ const word borrow = bigint_sub3(ws, mod, mod_sw, s, mod_sw);
+
+ // Compute either (t - s) or (t + (p - s)) depending on mask
+ const word carry = bigint_cnd_addsub(is_lt, t, ws, s, mod_sw);
+
+ BOTAN_DEBUG_ASSERT(borrow == 0 && carry == 0);
+ BOTAN_UNUSED(carry, borrow);
+ }
+
+template<size_t N>
+inline void bigint_mod_sub_n(word t[], const word s[], const word mod[], word ws[])
+ {
+ // is t < s or not?
+ const auto is_lt = bigint_ct_is_lt(t, N, s, N);
+
+ // ws = p - s
+ const word borrow = bigint_sub3(ws, mod, N, s, N);
+
+ // Compute either (t - s) or (t + (p - s)) depending on mask
+ const word carry = bigint_cnd_addsub(is_lt, t, ws, s, N);
+
+ BOTAN_DEBUG_ASSERT(borrow == 0 && carry == 0);
+ BOTAN_UNUSED(carry, borrow);
+ }
+
+/**
+* Compute ((n1<<bits) + n0) / d
+*/
+inline word bigint_divop(word n1, word n0, word d)
+ {
+ if(d == 0)
+ throw Invalid_Argument("bigint_divop divide by zero");
+
+#if defined(BOTAN_HAS_MP_DWORD)
+ return ((static_cast<dword>(n1) << BOTAN_MP_WORD_BITS) | n0) / d;
+#else
+
+ word high = n1 % d;
+ word quotient = 0;
+
+ for(size_t i = 0; i != BOTAN_MP_WORD_BITS; ++i)
+ {
+ const word high_top_bit = high >> (BOTAN_MP_WORD_BITS-1);
+
+ high <<= 1;
+ high |= (n0 >> (BOTAN_MP_WORD_BITS-1-i)) & 1;
+ quotient <<= 1;
+
+ if(high_top_bit || high >= d)
+ {
+ high -= d;
+ quotient |= 1;
+ }
+ }
+
+ return quotient;
+#endif
+ }
+
+/**
+* Compute ((n1<<bits) + n0) % d
+*/
+inline word bigint_modop(word n1, word n0, word d)
+ {
+ if(d == 0)
+ throw Invalid_Argument("bigint_modop divide by zero");
+
+#if defined(BOTAN_HAS_MP_DWORD)
+ return ((static_cast<dword>(n1) << BOTAN_MP_WORD_BITS) | n0) % d;
+#else
+ word z = bigint_divop(n1, n0, d);
+ word dummy = 0;
+ z = word_madd2(z, d, &dummy);
+ return (n0-z);
+#endif
+ }
+
+/*
+* Comba Multiplication / Squaring
+*/
+void bigint_comba_mul4(word z[8], const word x[4], const word y[4]);
+void bigint_comba_mul6(word z[12], const word x[6], const word y[6]);
+void bigint_comba_mul8(word z[16], const word x[8], const word y[8]);
+void bigint_comba_mul9(word z[18], const word x[9], const word y[9]);
+void bigint_comba_mul16(word z[32], const word x[16], const word y[16]);
+void bigint_comba_mul24(word z[48], const word x[24], const word y[24]);
+
+void bigint_comba_sqr4(word out[8], const word in[4]);
+void bigint_comba_sqr6(word out[12], const word in[6]);
+void bigint_comba_sqr8(word out[16], const word in[8]);
+void bigint_comba_sqr9(word out[18], const word in[9]);
+void bigint_comba_sqr16(word out[32], const word in[16]);
+void bigint_comba_sqr24(word out[48], const word in[24]);
+
+/**
+* Montgomery Reduction
+* @param z integer to reduce, of size exactly 2*(p_size+1).
+ Output is in the first p_size+1 words, higher
+ words are set to zero.
+* @param p modulus
+* @param p_size size of p
+* @param p_dash Montgomery value
+* @param workspace array of at least 2*(p_size+1) words
+* @param ws_size size of workspace in words
+*/
+void bigint_monty_redc(word z[],
+ const word p[], size_t p_size,
+ word p_dash,
+ word workspace[],
+ size_t ws_size);
+
+/*
+* High Level Multiplication/Squaring Interfaces
+*/
+
+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);
+
+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);
+
+}
+
+#endif
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