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diff --git a/comm/third_party/botan/src/lib/pubkey/mce/polyn_gf2m.h b/comm/third_party/botan/src/lib/pubkey/mce/polyn_gf2m.h
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+++ b/comm/third_party/botan/src/lib/pubkey/mce/polyn_gf2m.h
@@ -0,0 +1,174 @@
+/*
+ * (C) Copyright Projet SECRET, INRIA, Rocquencourt
+ * (C) Bhaskar Biswas and  Nicolas Sendrier
+ *
+ * (C) 2014 cryptosource GmbH
+ * (C) 2014 Falko Strenzke fstrenzke@cryptosource.de
+ *
+ * Botan is released under the Simplified BSD License (see license.txt)
+ *
+ */
+
+#ifndef BOTAN_POLYN_GF2M_H_
+#define BOTAN_POLYN_GF2M_H_
+
+#include <botan/secmem.h>
+#include <utility>
+#include <string>
+
+// Currently must be visible for MSVC
+//BOTAN_FUTURE_INTERNAL_HEADER(polyn_gf2m.h)
+
+namespace Botan {
+
+typedef uint16_t gf2m;
+
+class GF2m_Field;
+
+class RandomNumberGenerator;
+
+class polyn_gf2m
+   {
+   public:
+      /**
+      * create a zero polynomial:
+      */
+      explicit polyn_gf2m(std::shared_ptr<GF2m_Field> sp_field);
+
+      polyn_gf2m() : m_deg(-1) {}
+
+      polyn_gf2m(const secure_vector<uint8_t>& encoded, std::shared_ptr<GF2m_Field> sp_field);
+
+      polyn_gf2m& operator=(const polyn_gf2m&) = default;
+
+      /**
+      * create zero polynomial with reservation of space for a degree d polynomial
+      */
+      polyn_gf2m(int d, std::shared_ptr<GF2m_Field> sp_field);
+
+      polyn_gf2m(polyn_gf2m const& other);
+
+      /**
+      * random irreducible polynomial of degree t
+      */
+      polyn_gf2m(size_t t, RandomNumberGenerator& rng, std::shared_ptr<GF2m_Field> sp_field);
+
+      /** decode a polynomial from memory: **/
+      polyn_gf2m(const uint8_t* mem, uint32_t mem_len, std::shared_ptr<GF2m_Field> sp_field);
+
+      /**
+      *  create a polynomial from memory area (encoded)
+      */
+      polyn_gf2m(int degree, const uint8_t* mem, size_t mem_byte_len, std::shared_ptr<GF2m_Field> sp_field);
+
+      bool operator==(const polyn_gf2m & other) const ;
+
+      bool operator!=(const polyn_gf2m & other) const { return !(*this == other); }
+
+      polyn_gf2m(polyn_gf2m&& other)
+         {
+         this->swap(other);
+         }
+
+      polyn_gf2m & operator=(polyn_gf2m&& other)
+         {
+         if(this != &other)
+            {
+            this->swap(other);
+            }
+         return *this;
+         }
+
+      void swap(polyn_gf2m& other);
+
+      secure_vector<uint8_t> encode() const;
+
+      std::shared_ptr<GF2m_Field> get_sp_field() const
+         { return m_sp_field; }
+
+      gf2m& operator[](size_t i) { return coeff[i]; }
+
+      gf2m operator[](size_t i) const { return coeff[i]; }
+
+      gf2m get_lead_coef() const { return coeff[m_deg]; }
+
+      gf2m get_coef(size_t i) const { return coeff[i]; }
+
+      inline void set_coef(size_t i, gf2m v)
+         {
+         coeff[i] = v;
+         }
+
+      inline void add_to_coef(size_t i, gf2m v)
+         {
+         coeff[i] ^= v;
+         }
+
+      std::string to_string() const;
+
+      void encode(uint32_t min_numo_coeffs, uint8_t* mem, uint32_t mem_len) const;
+
+      int get_degree() const;
+
+      /**
+      * determine the degree in a timing secure manner. the timing of this function
+      * only depends on the number of allocated coefficients, not on the actual
+      * degree
+      */
+      int calc_degree_secure() const;
+
+      size_t degppf(const polyn_gf2m& g);
+
+      static std::vector<polyn_gf2m> sqmod_init(const polyn_gf2m & g);
+
+      static std::vector<polyn_gf2m> sqrt_mod_init(const polyn_gf2m & g);
+
+
+      polyn_gf2m sqmod(const std::vector<polyn_gf2m> & sq, int d);
+      void set_to_zero();
+      gf2m eval(gf2m a);
+
+      static std::pair<polyn_gf2m, polyn_gf2m> eea_with_coefficients(const polyn_gf2m & p,
+                                                                     const polyn_gf2m & g,
+                                                                     int break_deg);
+
+      void patchup_deg_secure( uint32_t trgt_deg, volatile gf2m patch_elem);
+
+   private:
+
+      void set_degree(int d) { m_deg = d; }
+
+      void poly_shiftmod( const polyn_gf2m & g);
+      void realloc(uint32_t new_size);
+      static polyn_gf2m gcd(polyn_gf2m const& p1, polyn_gf2m const& p2);
+
+      /**
+      * destructive:
+      */
+      static void remainder(polyn_gf2m & p, const polyn_gf2m & g);
+
+      static polyn_gf2m gcd_aux(polyn_gf2m& p1, polyn_gf2m& p2);
+   public:
+      // public member variable:
+      int m_deg;
+
+      // public member variable:
+      secure_vector<gf2m> coeff;
+
+      // public member variable:
+      std::shared_ptr<GF2m_Field> m_sp_field;
+   };
+
+gf2m random_gf2m(RandomNumberGenerator& rng);
+gf2m random_code_element(uint16_t code_length, RandomNumberGenerator& rng);
+
+std::vector<polyn_gf2m> syndrome_init(polyn_gf2m const& generator, std::vector<gf2m> const& support, int n);
+
+/**
+* Find the roots of a polynomial over GF(2^m) using the method by Federenko et al.
+*/
+secure_vector<gf2m> find_roots_gf2m_decomp(const polyn_gf2m & polyn, size_t code_length);
+
+}
+
+#endif