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diff --git a/comm/third_party/botan/src/lib/misc/fpe_fe1/fpe_fe1.h b/comm/third_party/botan/src/lib/misc/fpe_fe1/fpe_fe1.h
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+/*
+* Format Preserving Encryption (FE1 scheme)
+* (C) 2009,2018 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_FPE_FE1_H_
+#define BOTAN_FPE_FE1_H_
+
+#include <botan/sym_algo.h>
+#include <botan/bigint.h>
+
+namespace Botan {
+
+class Modular_Reducer;
+class MessageAuthenticationCode;
+
+/**
+* Format Preserving Encryption using the scheme FE1 from the paper
+* "Format-Preserving Encryption" by Bellare, Rogaway, et al
+* (https://eprint.iacr.org/2009/251)
+*/
+class BOTAN_PUBLIC_API(2,5) FPE_FE1 final : public SymmetricAlgorithm
+   {
+   public:
+
+      /**
+      * @param n the modulus. All plaintext and ciphertext values must be
+      *        less than this.
+      * @param rounds the number of rounds to use. Must be at least 3.
+      * @param compat_mode An error in versions before 2.5.0 chose incorrect
+      *        values for a and b. Set compat_mode to true to select this version.
+      * @param mac_algo the PRF to use as the encryption function
+      */
+      FPE_FE1(const BigInt& n,
+              size_t rounds = 5,
+              bool compat_mode = false,
+              const std::string& mac_algo = "HMAC(SHA-256)");
+
+      ~FPE_FE1();
+
+      Key_Length_Specification key_spec() const override;
+
+      std::string name() const override;
+
+      void clear() override;
+
+      /**
+      * Encrypt X from and onto the group Z_n using key and tweak
+      * @param x the plaintext to encrypt <= n
+      * @param tweak will modify the ciphertext
+      * @param tweak_len length of tweak
+      */
+      BigInt encrypt(const BigInt& x, const uint8_t tweak[], size_t tweak_len) const;
+
+      /**
+      * Decrypt X from and onto the group Z_n using key and tweak
+      * @param x the ciphertext to encrypt <= n
+      * @param tweak must match the value used to encrypt
+      * @param tweak_len length of tweak
+      */
+      BigInt decrypt(const BigInt& x, const uint8_t tweak[], size_t tweak_len) const;
+
+      BigInt encrypt(const BigInt& x, uint64_t tweak) const;
+
+      BigInt decrypt(const BigInt& x, uint64_t tweak) const;
+   private:
+      void key_schedule(const uint8_t key[], size_t length) override;
+
+      BigInt F(const BigInt& R, size_t round,
+               const secure_vector<uint8_t>& tweak,
+               secure_vector<uint8_t>& tmp) const;
+
+      secure_vector<uint8_t> compute_tweak_mac(const uint8_t tweak[], size_t tweak_len) const;
+
+      std::unique_ptr<MessageAuthenticationCode> m_mac;
+      std::unique_ptr<Modular_Reducer> mod_a;
+      std::vector<uint8_t> m_n_bytes;
+      BigInt m_a;
+      BigInt m_b;
+      size_t m_rounds;
+   };
+
+namespace FPE {
+
+/**
+* Format Preserving Encryption using the scheme FE1 from the paper
+* "Format-Preserving Encryption" by Bellare, Rogaway, et al
+* (https://eprint.iacr.org/2009/251)
+*
+* Encrypt X from and onto the group Z_n using key and tweak
+* @param n the modulus
+* @param X the plaintext as a BigInt
+* @param key a random key
+* @param tweak will modify the ciphertext (think of as an IV)
+*
+* @warning This function is hardcoded to use only 3 rounds which
+* may be insecure for some values of n. Prefer FPE_FE1 class
+*/
+BigInt BOTAN_PUBLIC_API(2,0) fe1_encrypt(const BigInt& n, const BigInt& X,
+                                         const SymmetricKey& key,
+                                         const std::vector<uint8_t>& tweak);
+
+/**
+* Decrypt X from and onto the group Z_n using key and tweak
+* @param n the modulus
+* @param X the ciphertext as a BigInt
+* @param key is the key used for encryption
+* @param tweak the same tweak used for encryption
+*
+* @warning This function is hardcoded to use only 3 rounds which
+* may be insecure for some values of n. Prefer FPE_FE1 class
+*/
+BigInt BOTAN_PUBLIC_API(2,0) fe1_decrypt(const BigInt& n, const BigInt& X,
+                                         const SymmetricKey& key,
+                                         const std::vector<uint8_t>& tweak);
+
+}
+
+}
+
+#endif