Merge GH #1129 Split up ffi.cpp

19 files changed, 2552 insertions, 2314 deletions

diff --git a/src/lib/ffi/ffi.cpp b/src/lib/ffi/ffi.cpp
index f13ab7b83..28eac401a 100644
--- a/src/lib/ffi/ffi.cpp
+++ b/src/lib/ffi/ffi.cpp
@@ -5,126 +5,13 @@
 */
 
 #include <botan/ffi.h>
-#include <botan/system_rng.h>
-#include <botan/exceptn.h>
-#include <botan/auto_rng.h>
-#include <botan/aead.h>
-#include <botan/block_cipher.h>
-#include <botan/hash.h>
-#include <botan/mac.h>
-#include <botan/pbkdf.h>
+#include <botan/internal/ffi_util.h>
 #include <botan/version.h>
-#include <botan/pkcs8.h>
-#include <botan/x509cert.h>
-#include <botan/data_src.h>
-#include <botan/pubkey.h>
-#include <botan/hex.h>
 #include <botan/mem_ops.h>
-#include <botan/x509_key.h>
-#include <botan/pk_algs.h>
-#include <botan/bigint.h>
-#include <botan/reducer.h>
-#include <botan/numthry.h>
-#include <botan/divide.h>
-#include <cstring>
-#include <memory>
-
-#if defined(BOTAN_HAS_RSA)
-  #include <botan/rsa.h>
-#endif
-
-#if defined(BOTAN_HAS_ELGAMAL)
-  #include <botan/elgamal.h>
-#endif
-
-#if defined(BOTAN_HAS_DSA)
-  #include <botan/dsa.h>
-#endif
-
-#if defined(BOTAN_HAS_ECDSA)
-  #include <botan/ecdsa.h>
-#endif
-
-#if defined(BOTAN_HAS_SM2)
-  #include <botan/sm2.h>
-#endif
-
-#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
-  #include <botan/ecc_key.h>
-#endif
-
-#if defined(BOTAN_HAS_DL_PUBLIC_KEY_FAMILY)
-  #include <botan/dl_algo.h>
-#endif
-
-#if defined(BOTAN_HAS_ECDH)
-  #include <botan/ecdh.h>
-#endif
-
-#if defined(BOTAN_HAS_CURVE_25519)
-  #include <botan/curve25519.h>
-#endif
-
-#if defined(BOTAN_HAS_ED25519)
-  #include <botan/ed25519.h>
-#endif
-
-#if defined(BOTAN_HAS_MCELIECE)
-  #include <botan/mceliece.h>
-#endif
-
-#if defined(BOTAN_HAS_MCEIES)
-  #include <botan/mceies.h>
-#endif
-
-#if defined(BOTAN_HAS_BCRYPT)
-  #include <botan/bcrypt.h>
-#endif
-
-#if defined(BOTAN_HAS_HASH_ID)
-  #include <botan/hash_id.h>
-#endif
-
-#if defined(BOTAN_HAS_TLS)
-  #include <botan/tls_client.h>
-  #include <botan/tls_server.h>
-#endif
-
-#if defined(BOTAN_HAS_RFC3394_KEYWRAP)
-   #include <botan/rfc3394.h>
-#endif
-
-namespace {
-
-#define BOTAN_ASSERT_ARG_NON_NULL(p) \
-   do { if(!p) throw Botan::Invalid_Argument("Argument " #p " is null"); } while(0)
-
-class FFI_Error : public Botan::Exception
-   {
-   public:
-      explicit FFI_Error(const std::string& what) : Exception("FFI error", what) {}
-   };
-
-template<typename T, uint32_t MAGIC>
-struct botan_struct
-   {
-   public:
-      botan_struct(T* obj) : m_magic(MAGIC), m_obj(obj) {}
-      ~botan_struct() { m_magic = 0; m_obj.reset(); }
-
-      bool magic_ok() const { return (m_magic == MAGIC); }
+#include <botan/hex.h>
+#include <cstdio>
 
-      T* get() const
-         {
-         if(magic_ok() == false)
-            throw FFI_Error("Bad magic " + std::to_string(m_magic) +
-                            " in ffi object expected " + std::to_string(MAGIC));
-         return m_obj.get();
-         }
-   private:
-      uint32_t m_magic = 0;
-      std::unique_ptr<T> m_obj;
-   };
+namespace Botan_FFI {
 
 int ffi_error_exception_thrown(const char* func_name, const char* exn)
    {
@@ -132,332 +19,11 @@ int ffi_error_exception_thrown(const char* func_name, const char* exn)
    return BOTAN_FFI_ERROR_EXCEPTION_THROWN;
    }
 
-template<typename T, uint32_t M>
-T& safe_get(botan_struct<T,M>* p)
-   {
-   if(!p)
-      throw FFI_Error("Null pointer argument");
-   if(T* t = p->get())
-      return *t;
-   throw FFI_Error("Invalid object pointer");
-   }
-
-template<typename T, uint32_t M>
-const T& safe_get(const botan_struct<T,M>* p)
-   {
-   if(!p)
-      throw FFI_Error("Null pointer argument");
-   if(const T* t = p->get())
-      return *t;
-   throw FFI_Error("Invalid object pointer");
-   }
-
-template<typename Thunk>
-int ffi_guard_thunk(const char* func_name, Thunk thunk)
-   {
-   try
-      {
-      return thunk();
-      }
-   catch(std::bad_alloc)
-      {
-      return ffi_error_exception_thrown(func_name, "bad_alloc");
-      }
-   catch(std::exception& e)
-      {
-      return ffi_error_exception_thrown(func_name, e.what());
-      }
-   catch(...)
-      {
-      return ffi_error_exception_thrown(func_name, "unknown exception");
-      }
-
-   return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
-   }
-
-#define BOTAN_GUARD_BLOCK(b) ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, []() t))
-
-template<typename T, uint32_t M, typename F>
-int apply_fn(botan_struct<T, M>* o, const char* func_name, F func)
-   {
-   try
-      {
-      if(!o)
-         throw FFI_Error("Null object to " + std::string(func_name));
-      if(T* t = o->get())
-         return func(*t);
-      }
-   catch(std::bad_alloc)
-      {
-      return ffi_error_exception_thrown(func_name, "bad_alloc");
-      }
-   catch(std::exception& e)
-      {
-      return ffi_error_exception_thrown(func_name, e.what());
-      }
-   catch(...)
-      {
-      return ffi_error_exception_thrown(func_name, "unknown exception");
-      }
-
-   return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
-   }
-
-#define BOTAN_FFI_DO(T, obj, param, block)                              \
-   apply_fn(obj, BOTAN_CURRENT_FUNCTION,                                \
-            [=](T& param) -> int { do { block } while(0); return BOTAN_FFI_SUCCESS; })
-
-template<typename T, uint32_t M>
-int ffi_delete_object(botan_struct<T, M>* obj, const char* func_name)
-   {
-   try
-      {
-      if(obj == nullptr)
-         return BOTAN_FFI_SUCCESS; // ignore delete of null objects
-
-      if(obj->magic_ok() == false)
-         return BOTAN_FFI_ERROR_INVALID_INPUT;
-
-      delete obj;
-      return BOTAN_FFI_SUCCESS;
-      }
-   catch(std::exception& e)
-      {
-      return ffi_error_exception_thrown(func_name, e.what());
-      }
-   catch(...)
-      {
-      return ffi_error_exception_thrown(func_name, "unknown exception");
-      }
-   }
-
-#define BOTAN_FFI_CHECKED_DELETE(o) ffi_delete_object(o, BOTAN_CURRENT_FUNCTION)
-
-inline int write_output(uint8_t out[], size_t* out_len, const uint8_t buf[], size_t buf_len)
-   {
-   const size_t avail = *out_len;
-   *out_len = buf_len;
-
-   if(avail >= buf_len)
-      {
-      Botan::copy_mem(out, buf, buf_len);
-      return BOTAN_FFI_SUCCESS;
-      }
-   else
-      {
-      Botan::clear_mem(out, avail);
-      return BOTAN_FFI_ERROR_INSUFFICIENT_BUFFER_SPACE;
-      }
-   }
-
-template<typename Alloc>
-int write_vec_output(uint8_t out[], size_t* out_len, const std::vector<uint8_t, Alloc>& buf)
-   {
-   return write_output(out, out_len, buf.data(), buf.size());
-   }
-
-inline int write_str_output(uint8_t out[], size_t* out_len, const std::string& str)
-   {
-   return write_output(out, out_len,
-                       reinterpret_cast<const uint8_t*>(str.c_str()),
-                       str.size() + 1);
-   }
-
-inline int write_str_output(char out[], size_t* out_len, const std::string& str)
-   {
-   return write_str_output(reinterpret_cast<uint8_t*>(out), out_len, str);
-   }
-
-inline int write_str_output(char out[], size_t* out_len, const std::vector<uint8_t>& str_vec)
-   {
-   return write_output(reinterpret_cast<uint8_t*>(out), out_len,
-                       reinterpret_cast<const uint8_t*>(str_vec.data()),
-                       str_vec.size());
-   }
-
-Botan::BigInt pubkey_get_field(const Botan::Public_Key& key,
-                               const std::string& field)
-   {
-   // Maybe this should be `return key.get_integer_field(field_name)`?
-
-#if defined(BOTAN_HAS_RSA)
-   if(const Botan::RSA_PublicKey* rsa = dynamic_cast<const Botan::RSA_PublicKey*>(&key))
-      {
-      if(field == "n")
-         return rsa->get_n();
-      else if(field == "e")
-         return rsa->get_e();
-      else
-         throw Botan::Exception("Field not supported");
-      }
-#endif
-
-#if defined(BOTAN_HAS_DL_PUBLIC_KEY_FAMILY)
-   // Handles DSA, ElGamal, etc
-   if(const Botan::DL_Scheme_PublicKey* dl = dynamic_cast<const Botan::DL_Scheme_PublicKey*>(&key))
-      {
-      if(field == "p")
-         return dl->group_p();
-      else if(field == "q")
-         return dl->group_q();
-      else if(field == "g")
-         return dl->group_g();
-      else if(field == "y")
-         return dl->get_y();
-      else
-         throw Botan::Exception("Field not supported");
-      }
-#endif
-
-#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
-   if(const Botan::EC_PublicKey* ecc = dynamic_cast<const Botan::EC_PublicKey*>(&key))
-      {
-      if(field == "public_x")
-         return ecc->public_point().get_affine_x();
-      else if(field == "public_y")
-         return ecc->public_point().get_affine_y();
-      else if(field == "base_x")
-         return ecc->domain().get_base_point().get_affine_x();
-      else if(field == "base_y")
-         return ecc->domain().get_base_point().get_affine_y();
-      else if(field == "p")
-         return ecc->domain().get_curve().get_p();
-      else if(field == "a")
-         return ecc->domain().get_curve().get_a();
-      else if(field == "b")
-         return ecc->domain().get_curve().get_b();
-      else if(field == "cofactor")
-         return ecc->domain().get_cofactor();
-      else if(field == "order")
-         return ecc->domain().get_order();
-      else
-         throw Botan::Exception("Field not supported");
-      }
-#endif
-
-   // Some other algorithm type not supported by this function
-   throw Botan::Exception("Unsupported algorithm type for botan_pubkey_get_field");
-   }
-
-Botan::BigInt privkey_get_field(const Botan::Private_Key& key,
-                                const std::string& field)
-   {
-   //return key.get_integer_field(field);
-
-#if defined(BOTAN_HAS_RSA)
-
-   if(const Botan::RSA_PrivateKey* rsa = dynamic_cast<const Botan::RSA_PrivateKey*>(&key))
-      {
-      if(field == "p")
-         return rsa->get_p();
-      else if(field == "q")
-         return rsa->get_q();
-      else if(field == "d")
-         return rsa->get_d();
-      else if(field == "c")
-         return rsa->get_c();
-      else if(field == "d1")
-         return rsa->get_d1();
-      else if(field == "d2")
-         return rsa->get_d2();
-      else
-         return pubkey_get_field(key, field);
-      }
-#endif
-
-#if defined(BOTAN_HAS_DL_PUBLIC_KEY_FAMILY)
-   // Handles DSA, ElGamal, etc
-   if(const Botan::DL_Scheme_PrivateKey* dl = dynamic_cast<const Botan::DL_Scheme_PrivateKey*>(&key))
-      {
-      if(field == "x")
-         return dl->get_x();
-      else
-         return pubkey_get_field(key, field);
-      }
-#endif
-
-#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
-   if(const Botan::EC_PrivateKey* ecc = dynamic_cast<const Botan::EC_PrivateKey*>(&key))
-      {
-      if(field == "x")
-         return ecc->private_value();
-      else
-         return pubkey_get_field(key, field);
-      }
-#endif
-
-   // Some other algorithm type not supported by this function
-   throw Botan::Exception("Unsupported algorithm type for botan_privkey_get_field");
-   }
-
-#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
-
-// These are always called within an existing try/catch block
-
-template<class ECPrivateKey_t>
-int privkey_load_ec(std::unique_ptr<ECPrivateKey_t>& key,
-                    const Botan::BigInt& scalar,
-                    const char* curve_name)
-   {
-   if(curve_name == nullptr)
-      return BOTAN_FFI_ERROR_NULL_POINTER;
-
-   Botan::Null_RNG null_rng;
-   Botan::EC_Group grp(curve_name);
-   key.reset(new ECPrivateKey_t(null_rng, grp, scalar));
-   return BOTAN_FFI_SUCCESS;
-   }
-
-template<class ECPublicKey_t>
-int pubkey_load_ec(std::unique_ptr<ECPublicKey_t>& key,
-                   const Botan::BigInt& public_x,
-                   const Botan::BigInt& public_y,
-                   const char* curve_name)
-   {
-   if(curve_name == nullptr)
-      return BOTAN_FFI_ERROR_NULL_POINTER;
-
-   Botan::Null_RNG null_rng;
-   Botan::EC_Group grp(curve_name);
-   Botan::PointGFp uncompressed_point(grp.get_curve(), public_x, public_y);
-   key.reset(new ECPublicKey_t(grp, uncompressed_point));
-   return BOTAN_FFI_SUCCESS;
-   }
-
-#endif
-
-} // closes anonymous namespace
+}
 
 extern "C" {
 
-#define BOTAN_FFI_DECLARE_STRUCT(NAME, TYPE, MAGIC) \
-   struct NAME : public botan_struct<TYPE, MAGIC> { explicit NAME(TYPE* x) : botan_struct(x) {} }
-
-struct botan_cipher_struct : public botan_struct<Botan::Cipher_Mode, 0xB4A2BF9C>
-   {
-   explicit botan_cipher_struct(Botan::Cipher_Mode* x) : botan_struct(x) {}
-   Botan::secure_vector<uint8_t> m_buf;
-   };
-
-BOTAN_FFI_DECLARE_STRUCT(botan_rng_struct, Botan::RandomNumberGenerator, 0x4901F9C1);
-BOTAN_FFI_DECLARE_STRUCT(botan_mp_struct, Botan::BigInt, 0xC828B9D2);
-BOTAN_FFI_DECLARE_STRUCT(botan_block_cipher_struct, Botan::BlockCipher, 0x64C29716);
-BOTAN_FFI_DECLARE_STRUCT(botan_hash_struct, Botan::HashFunction, 0x1F0A4F84);
-BOTAN_FFI_DECLARE_STRUCT(botan_mac_struct, Botan::MessageAuthenticationCode, 0xA06E8FC1);
-BOTAN_FFI_DECLARE_STRUCT(botan_pubkey_struct, Botan::Public_Key, 0x2C286519);
-BOTAN_FFI_DECLARE_STRUCT(botan_privkey_struct, Botan::Private_Key, 0x7F96385E);
-BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_encrypt_struct, Botan::PK_Encryptor, 0x891F3FC3);
-BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_decrypt_struct, Botan::PK_Decryptor, 0x912F3C37);
-BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_sign_struct, Botan::PK_Signer, 0x1AF0C39F);
-BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_verify_struct, Botan::PK_Verifier, 0x2B91F936);
-BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_ka_struct, Botan::PK_Key_Agreement, 0x2939CAB1);
-
-BOTAN_FFI_DECLARE_STRUCT(botan_x509_cert_struct, Botan::X509_Certificate, 0x8F628937);
-
-
-#if defined(BOTAN_HAS_TLS)
-BOTAN_FFI_DECLARE_STRUCT(botan_tls_channel_struct, Botan::TLS::Channel, 0x0212FE99);
-#endif
+using namespace Botan_FFI;
 
 /*
 * Versioning
@@ -508,1866 +74,5 @@ int botan_hex_encode(const uint8_t* in, size_t len, char* out, uint32_t flags)
       });
    }
 
-int botan_rng_init(botan_rng_t* rng_out, const char* rng_type)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_ARG_NON_NULL(rng_out);
-
-      const std::string rng_type_s(rng_type ? rng_type : "system");
-
-      std::unique_ptr<Botan::RandomNumberGenerator> rng;
-
-      if(rng_type_s == "system")
-         rng.reset(new Botan::System_RNG);
-      else if(rng_type_s == "user")
-         rng.reset(new Botan::AutoSeeded_RNG);
-      else
-         return BOTAN_FFI_ERROR_BAD_PARAMETER;
-
-      *rng_out = new botan_rng_struct(rng.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_rng_destroy(botan_rng_t rng)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(rng);
-   }
-
-int botan_rng_get(botan_rng_t rng, uint8_t* out, size_t out_len)
-   {
-   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.randomize(out, out_len); });
-   }
-
-int botan_rng_reseed(botan_rng_t rng, size_t bits)
-   {
-   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.reseed_from_rng(Botan::system_rng(), bits); });
-   }
-
-int botan_mp_init(botan_mp_t* mp_out)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_ARG_NON_NULL(mp_out);
-
-      *mp_out = new botan_mp_struct(new Botan::BigInt);
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_mp_clear(botan_mp_t mp)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.clear(); });
-   }
-
-int botan_mp_set_from_int(botan_mp_t mp, int initial_value)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
-      if(initial_value >= 0)
-         {
-         bn = Botan::BigInt(static_cast<uint64_t>(initial_value));
-         }
-      else
-         {
-         bn = Botan::BigInt(static_cast<uint64_t>(-initial_value));
-         bn.flip_sign();
-         }
-      });
-   }
-
-int botan_mp_set_from_str(botan_mp_t mp, const char* str)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn = Botan::BigInt(str); });
-   }
-
-int botan_mp_set_from_radix_str(botan_mp_t mp, const char* str, size_t radix)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
-      Botan::BigInt::Base base;
-      if(radix == 10)
-         base = Botan::BigInt::Decimal;
-      else if(radix == 16)
-         base = Botan::BigInt::Hexadecimal;
-      else
-         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-
-      const uint8_t* bytes = reinterpret_cast<const uint8_t*>(str);
-      const size_t len = strlen(str);
-
-      bn = Botan::BigInt::decode(bytes, len, base);
-      });
-   }
-
-int botan_mp_set_from_mp(botan_mp_t dest, const botan_mp_t source)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, dest, bn, { bn = safe_get(source); });
-   }
-
-int botan_mp_is_negative(const botan_mp_t mp)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_negative() ? 1 : 0; });
-   }
-
-int botan_mp_is_positive(const botan_mp_t mp)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_positive() ? 1 : 0; });
-   }
-
-int botan_mp_flip_sign(botan_mp_t mp)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.flip_sign(); });
-   }
-
-int botan_mp_from_bin(botan_mp_t mp, const uint8_t bin[], size_t bin_len)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.binary_decode(bin, bin_len); });
-   }
-
-int botan_mp_to_hex(const botan_mp_t mp, char* out)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
-      std::vector<uint8_t> hex = Botan::BigInt::encode(bn, Botan::BigInt::Hexadecimal);
-      std::memcpy(out, hex.data(), hex.size());
-      out[hex.size()] = 0; // null terminate
-      });
-   }
-
-int botan_mp_to_str(const botan_mp_t mp, uint8_t digit_base, char* out, size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
-      Botan::BigInt::Base base;
-      if(digit_base == 0 || digit_base == 10)
-         base = Botan::BigInt::Decimal;
-      else if(digit_base == 16)
-         base = Botan::BigInt::Hexadecimal;
-      else
-         throw FFI_Error("botan_mp_to_str invalid digit base");
-
-      std::vector<uint8_t> hex = Botan::BigInt::encode(bn, base);
-      hex.push_back(0); // null terminator
-      return write_str_output(out, out_len, hex);
-      });
-   }
-
-int botan_mp_to_bin(const botan_mp_t mp, uint8_t vec[])
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.binary_encode(vec); });
-   }
-
-int botan_mp_to_uint32(const botan_mp_t mp, uint32_t* val)
-   {
-   if(val == nullptr) {
-   return BOTAN_FFI_ERROR_NULL_POINTER;
-   }
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { *val = bn.to_u32bit(); });
-   }
-
-int botan_mp_destroy(botan_mp_t mp)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(mp);
-   }
-
-int botan_mp_add(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) + safe_get(y); });
-   }
-
-int botan_mp_sub(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) - safe_get(y); });
-   }
-
-int botan_mp_mul(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) * safe_get(y); });
-   }
-
-int botan_mp_div(botan_mp_t quotient,
-                 botan_mp_t remainder,
-                 const botan_mp_t x, const botan_mp_t y)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, quotient, q, {
-      Botan::BigInt r;
-      Botan::divide(safe_get(x), safe_get(y), q, r);
-      safe_get(remainder) = r;
-      });
-   }
-
-int botan_mp_equal(const botan_mp_t x_w, const botan_mp_t y_w)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { return x == safe_get(y_w); });
-   }
-
-int botan_mp_is_zero(const botan_mp_t mp)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_zero(); });
-   }
-
-int botan_mp_is_odd(const botan_mp_t mp)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_odd(); });
-   }
-
-int botan_mp_is_even(const botan_mp_t mp)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_even(); });
-   }
-
-int botan_mp_cmp(int* result, const botan_mp_t x_w, const botan_mp_t y_w)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { *result = x.cmp(safe_get(y_w)); });
-   }
-
-int botan_mp_swap(botan_mp_t x_w, botan_mp_t y_w)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { x.swap(safe_get(y_w)); });
-   }
-
-// Return (base^exponent) % modulus
-int botan_mp_powmod(botan_mp_t out, const botan_mp_t base, const botan_mp_t exponent, const botan_mp_t modulus)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, out, o,
-                       { o = Botan::power_mod(safe_get(base), safe_get(exponent), safe_get(modulus)); });
-   }
-
-int botan_mp_lshift(botan_mp_t out, const botan_mp_t in, size_t shift)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = safe_get(in) << shift; });
-   }
-
-int botan_mp_rshift(botan_mp_t out, const botan_mp_t in, size_t shift)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = safe_get(in) >> shift; });
-   }
-
-int botan_mp_mod_inverse(botan_mp_t out, const botan_mp_t in, const botan_mp_t modulus)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = Botan::inverse_mod(safe_get(in), safe_get(modulus)); });
-   }
-
-int botan_mp_mod_mul(botan_mp_t out, const botan_mp_t x, const botan_mp_t y, const botan_mp_t modulus)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, out, o, {
-      Botan::Modular_Reducer reducer(safe_get(modulus));
-      o = reducer.multiply(safe_get(x), safe_get(y));
-      });
-   }
-
-int botan_mp_rand_bits(botan_mp_t rand_out, botan_rng_t rng, size_t bits)
-   {
-   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, {
-      safe_get(rand_out).randomize(r, bits); });
-   }
-
-int botan_mp_rand_range(botan_mp_t rand_out,
-                        botan_rng_t rng,
-                        const botan_mp_t lower,
-                        const botan_mp_t upper)
-   {
-   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, {
-      safe_get(rand_out) = Botan::BigInt::random_integer(r, safe_get(lower), safe_get(upper)); });
-   }
-
-int botan_mp_gcd(botan_mp_t out, const botan_mp_t x, const botan_mp_t y)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, out, o, {
-      o = Botan::gcd(safe_get(x), safe_get(y)); });
-   }
-
-int botan_mp_is_prime(const botan_mp_t mp, botan_rng_t rng, size_t test_prob)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, n,
-                       { return (Botan::is_prime(n, safe_get(rng), test_prob)) ? 1 : 0; });
-   }
-
-int botan_mp_get_bit(const botan_mp_t mp, size_t bit)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { return (n.get_bit(bit)); });
-   }
-
-int botan_mp_set_bit(botan_mp_t mp, size_t bit)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { n.set_bit(bit); });
-   }
-
-int botan_mp_clear_bit(botan_mp_t mp, size_t bit)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { n.clear_bit(bit); });
-   }
-
-int botan_mp_num_bits(const botan_mp_t mp, size_t* bits)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { *bits = n.bits(); });
-   }
-
-int botan_mp_num_bytes(const botan_mp_t mp, size_t* bytes)
-   {
-   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { *bytes = n.bytes(); });
-   }
-
-int botan_block_cipher_init(botan_block_cipher_t* bc, const char* bc_name)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(bc == nullptr || bc_name == nullptr || *bc_name == 0)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      *bc = nullptr;
-
-      std::unique_ptr<Botan::BlockCipher> cipher(Botan::BlockCipher::create(bc_name));
-      if(cipher == nullptr)
-         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-
-      *bc = new botan_block_cipher_struct(cipher.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-/**
-* Destroy a block cipher object
-*/
-int botan_block_cipher_destroy(botan_block_cipher_t bc)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(bc);
-   }
-
-int botan_block_cipher_clear(botan_block_cipher_t bc)
-   {
-   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.clear(); });
-   }
-
-/**
-* Set the key for a block cipher instance
-*/
-int botan_block_cipher_set_key(botan_block_cipher_t bc,
-                               const uint8_t key[], size_t len)
-   {
-   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.set_key(key, len); });
-   }
-
-/**
-* Return the positive block size of this block cipher, or negative to
-* indicate an error
-*/
-int botan_block_cipher_block_size(botan_block_cipher_t bc)
-   {
-   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { return b.block_size(); });
-   }
-
-int botan_block_cipher_encrypt_blocks(botan_block_cipher_t bc,
-                                      const uint8_t in[],
-                                      uint8_t out[],
-                                      size_t blocks)
-   {
-   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.encrypt_n(in, out, blocks); });
-   }
-
-int botan_block_cipher_decrypt_blocks(botan_block_cipher_t bc,
-                                      const uint8_t in[],
-                                      uint8_t out[],
-                                      size_t blocks)
-   {
-   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.decrypt_n(in, out, blocks); });
-   }
-
-int botan_hash_init(botan_hash_t* hash, const char* hash_name, uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(hash == nullptr || hash_name == nullptr || *hash_name == 0)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-      if(flags != 0)
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-
-      std::unique_ptr<Botan::HashFunction> h = Botan::HashFunction::create(hash_name);
-      if(h == nullptr)
-         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-
-      *hash = new botan_hash_struct(h.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_hash_destroy(botan_hash_t hash)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(hash);
-   }
-
-int botan_hash_output_length(botan_hash_t hash, size_t* out)
-   {
-   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { *out = h.output_length(); });
-   }
-
-int botan_hash_block_size(botan_hash_t hash, size_t* out)
-   {
-   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { *out = h.hash_block_size(); });
-   }
-
-int botan_hash_clear(botan_hash_t hash)
-   {
-   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { h.clear(); });
-   }
-
-int botan_hash_update(botan_hash_t hash, const uint8_t* buf, size_t len)
-   {
-   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { h.update(buf, len); });
-   }
-
-int botan_hash_final(botan_hash_t hash, uint8_t out[])
-   {
-   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { h.final(out); });
-   }
-
-int botan_hash_copy_state(botan_hash_t* dest, const botan_hash_t source)
-   {
-   return BOTAN_FFI_DO(Botan::HashFunction, source, src, {
-      *dest = new botan_hash_struct(src.copy_state().release()); });
-   }
-
-int botan_mac_init(botan_mac_t* mac, const char* mac_name, uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(!mac || !mac_name || flags != 0)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      std::unique_ptr<Botan::MessageAuthenticationCode> m =
-         Botan::MessageAuthenticationCode::create(mac_name);
-
-      if(m == nullptr)
-         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-
-      *mac = new botan_mac_struct(m.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_mac_destroy(botan_mac_t mac)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(mac);
-   }
-
-int botan_mac_set_key(botan_mac_t mac, const uint8_t* key, size_t key_len)
-   {
-   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.set_key(key, key_len); });
-   }
-
-int botan_mac_output_length(botan_mac_t mac, size_t* out)
-   {
-   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { *out = m.output_length(); });
-   }
-
-int botan_mac_clear(botan_mac_t mac)
-   {
-   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.clear(); });
-   }
-
-int botan_mac_update(botan_mac_t mac, const uint8_t* buf, size_t len)
-   {
-   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.update(buf, len); });
-   }
-
-int botan_mac_final(botan_mac_t mac, uint8_t out[])
-   {
-   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.final(out); });
-   }
-
-int botan_cipher_init(botan_cipher_t* cipher, const char* cipher_name, uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      const bool encrypt_p = ((flags & BOTAN_CIPHER_INIT_FLAG_MASK_DIRECTION) == BOTAN_CIPHER_INIT_FLAG_ENCRYPT);
-      const Botan::Cipher_Dir dir = encrypt_p ? Botan::ENCRYPTION : Botan::DECRYPTION;
-      std::unique_ptr<Botan::Cipher_Mode> mode(Botan::get_cipher_mode(cipher_name, dir));
-      if(!mode)
-         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-      *cipher = new botan_cipher_struct(mode.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_cipher_destroy(botan_cipher_t cipher)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(cipher);
-   }
-
-int botan_cipher_clear(botan_cipher_t cipher)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { c.clear(); });
-   }
-
-int botan_cipher_query_keylen(botan_cipher_t cipher,
-                              size_t* out_minimum_keylength,
-                              size_t* out_maximum_keylength)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, {
-      *out_minimum_keylength = c.key_spec().minimum_keylength();
-      *out_maximum_keylength = c.key_spec().maximum_keylength();
-      });
-   }
-
-int botan_cipher_set_key(botan_cipher_t cipher,
-                         const uint8_t* key, size_t key_len)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { c.set_key(key, key_len); });
-   }
-
-int botan_cipher_start(botan_cipher_t cipher_obj,
-                       const uint8_t* nonce, size_t nonce_len)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::Cipher_Mode& cipher = safe_get(cipher_obj);
-      cipher.start(nonce, nonce_len);
-      cipher_obj->m_buf.reserve(cipher.update_granularity());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_cipher_update(botan_cipher_t cipher_obj,
-                        uint32_t flags,
-                        uint8_t output_ptr[],
-                        size_t orig_output_size,
-                        size_t* output_written,
-                        const uint8_t input_ptr[],
-                        size_t orig_input_size,
-                        size_t* input_consumed)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-
-      size_t input_size = orig_input_size;
-      size_t output_size = orig_output_size;
-      const uint8_t* input = input_ptr;
-      uint8_t* output = output_ptr;
-
-      using namespace Botan;
-      Cipher_Mode& cipher = safe_get(cipher_obj);
-      secure_vector<uint8_t>& mbuf = cipher_obj->m_buf;
-
-      const bool final_input = (flags & BOTAN_CIPHER_UPDATE_FLAG_FINAL);
-
-      if(final_input)
-         {
-         mbuf.assign(input, input + input_size);
-         *input_consumed = input_size;
-         *output_written = 0;
-
-         try
-            {
-            cipher.finish(mbuf);
-            }
-         catch(Integrity_Failure& e)
-            {
-            return BOTAN_FFI_ERROR_BAD_MAC;
-            }
-
-         *output_written = mbuf.size();
-
-         if(mbuf.size() <= output_size)
-            {
-            copy_mem(output, mbuf.data(), mbuf.size());
-            mbuf.clear();
-            return BOTAN_FFI_SUCCESS;
-            }
-
-         return -1;
-         }
-
-      if(input_size == 0)
-         {
-         // Currently must take entire buffer in this case
-         *output_written = mbuf.size();
-         if(output_size >= mbuf.size())
-            {
-            copy_mem(output, mbuf.data(), mbuf.size());
-            mbuf.clear();
-            return BOTAN_FFI_SUCCESS;
-            }
-
-         return -1;
-         }
-
-      const size_t ud = cipher.update_granularity();
-      BOTAN_ASSERT(cipher.update_granularity() > cipher.minimum_final_size(), "logic error");
-
-      mbuf.resize(ud);
-      size_t taken = 0, written = 0;
-
-      while(input_size >= ud && output_size >= ud)
-         {
-         copy_mem(mbuf.data(), input, ud);
-         cipher.update(mbuf);
-
-         input_size -= ud;
-         copy_mem(output, mbuf.data(), ud);
-         input += ud;
-         taken += ud;
-
-         output_size -= ud;
-         output += ud;
-         written += ud;
-         }
-
-      *output_written = written;
-      *input_consumed = taken;
-
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_cipher_set_associated_data(botan_cipher_t cipher,
-                                     const uint8_t* ad,
-                                     size_t ad_len)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, {
-      if(Botan::AEAD_Mode* aead = dynamic_cast<Botan::AEAD_Mode*>(&c))
-         {
-         aead->set_associated_data(ad, ad_len);
-         return BOTAN_FFI_SUCCESS;
-         }
-      return BOTAN_FFI_ERROR_BAD_PARAMETER;
-      });
-   }
-
-int botan_cipher_valid_nonce_length(botan_cipher_t cipher, size_t nl)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { return c.valid_nonce_length(nl) ? 1 : 0; });
-   }
-
-int botan_cipher_get_default_nonce_length(botan_cipher_t cipher, size_t* nl)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *nl = c.default_nonce_length(); });
-   }
-
-int botan_cipher_get_update_granularity(botan_cipher_t cipher, size_t* ug)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *ug = c.update_granularity(); });
-   }
-
-int botan_cipher_get_tag_length(botan_cipher_t cipher, size_t* tl)
-   {
-   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *tl = c.tag_size(); });
-   }
-
-int botan_pbkdf(const char* pbkdf_algo, uint8_t out[], size_t out_len,
-                const char* pass, const uint8_t salt[], size_t salt_len,
-                size_t iterations)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::PBKDF> pbkdf(Botan::get_pbkdf(pbkdf_algo));
-      pbkdf->pbkdf_iterations(out, out_len, pass, salt, salt_len, iterations);
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_pbkdf_timed(const char* pbkdf_algo,
-                      uint8_t out[], size_t out_len,
-                      const char* password,
-                      const uint8_t salt[], size_t salt_len,
-                      size_t ms_to_run,
-                      size_t* iterations_used)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::PBKDF> pbkdf(Botan::get_pbkdf(pbkdf_algo));
-      pbkdf->pbkdf_timed(out, out_len, password, salt, salt_len,
-                         std::chrono::milliseconds(ms_to_run),
-                         *iterations_used);
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_kdf(const char* kdf_algo,
-              uint8_t out[], size_t out_len,
-              const uint8_t secret[], size_t secret_len,
-              const uint8_t salt[], size_t salt_len,
-              const uint8_t label[], size_t label_len)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::KDF> kdf(Botan::get_kdf(kdf_algo));
-      kdf->kdf(out, out_len, secret, secret_len, salt, salt_len, label, label_len);
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_bcrypt_generate(uint8_t* out, size_t* out_len,
-                          const char* pass,
-                          botan_rng_t rng_obj, size_t wf,
-                          uint32_t flags)
-   {
-#if defined(BOTAN_HAS_BCRYPT)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_ARG_NON_NULL(out);
-      BOTAN_ASSERT_ARG_NON_NULL(out_len);
-      BOTAN_ASSERT_ARG_NON_NULL(pass);
-
-      if(flags != 0)
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-
-      if(wf < 2 || wf > 30)
-         throw FFI_Error("Bad bcrypt work factor " + std::to_string(wf));
-
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-      const std::string bcrypt = Botan::generate_bcrypt(pass, rng, wf);
-      return write_str_output(out, out_len, bcrypt);
-      });
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_bcrypt_is_valid(const char* pass, const char* hash)
-   {
-#if defined(BOTAN_HAS_BCRYPT)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      return Botan::check_bcrypt(pass, hash) ? 0 : 1;
-      });
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_create(botan_privkey_t* key_obj,
-                         const char* algo_name,
-                         const char* algo_params,
-                         botan_rng_t rng_obj)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(key_obj == nullptr)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      *key_obj = nullptr;
-      if(rng_obj == nullptr)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-      std::unique_ptr<Botan::Private_Key> key(
-         Botan::create_private_key(algo_name ? algo_name : "RSA",
-                                   rng,
-                                   algo_params ? algo_params : ""));
-
-      if(key)
-         {
-         *key_obj = new botan_privkey_struct(key.release());
-         return BOTAN_FFI_SUCCESS;
-         }
-      else
-         {
-         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-         }
-      });
-   }
-
-int botan_privkey_create_rsa(botan_privkey_t* key_obj, botan_rng_t rng_obj, size_t n_bits)
-   {
-#if defined(BOTAN_HAS_RSA)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(key_obj == nullptr || rng_obj == nullptr)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-      if(n_bits < 1024 || n_bits > 16*1024)
-         return BOTAN_FFI_ERROR_BAD_PARAMETER;
-
-      *key_obj = nullptr;
-
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-      std::unique_ptr<Botan::Private_Key> key(new Botan::RSA_PrivateKey(rng, n_bits));
-      *key_obj = new botan_privkey_struct(key.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_create_ecdsa(botan_privkey_t* key_obj, botan_rng_t rng_obj, const char* param_str)
-   {
-#if defined(BOTAN_HAS_ECDSA)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(key_obj == nullptr || rng_obj == nullptr || param_str == nullptr || *param_str == 0)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      *key_obj = nullptr;
-
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-      Botan::EC_Group grp(param_str);
-      std::unique_ptr<Botan::Private_Key> key(new Botan::ECDSA_PrivateKey(rng, grp));
-      *key_obj = new botan_privkey_struct(key.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-     return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_create_mceliece(botan_privkey_t* key_obj, botan_rng_t rng_obj, size_t n, size_t t)
-   {
-#if defined(BOTAN_HAS_MCELIECE)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(key_obj == nullptr || rng_obj == nullptr || n == 0 || t == 0)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      *key_obj = nullptr;
-
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-      std::unique_ptr<Botan::Private_Key> key(new Botan::McEliece_PrivateKey(rng, n, t));
-      *key_obj = new botan_privkey_struct(key.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_create_ecdh(botan_privkey_t* key_obj, botan_rng_t rng_obj, const char* param_str)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(key_obj == nullptr || rng_obj == nullptr || param_str == nullptr || *param_str == 0)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      *key_obj = nullptr;
-
-      const std::string params(param_str);
-
-#if defined(BOTAN_HAS_CURVE_25519)
-      if(params == "curve25519")
-         {
-         std::unique_ptr<Botan::Private_Key> key(new Botan::Curve25519_PrivateKey(safe_get(rng_obj)));
-         *key_obj = new botan_privkey_struct(key.release());
-         return BOTAN_FFI_SUCCESS;
-         }
-#endif
-
-#if defined(BOTAN_HAS_ECDH)
-      Botan::EC_Group grp(params);
-      std::unique_ptr<Botan::Private_Key> key(new Botan::ECDH_PrivateKey(safe_get(rng_obj), grp));
-      *key_obj = new botan_privkey_struct(key.release());
-      return BOTAN_FFI_SUCCESS;
-#endif
-
-      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-      });
-   }
-
-int botan_privkey_load(botan_privkey_t* key, botan_rng_t rng_obj,
-                       const uint8_t bits[], size_t len,
-                       const char* password)
-   {
-   *key = nullptr;
-
-   if(password == nullptr)
-      password = "";
-
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::DataSource_Memory src(bits, len);
-
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-
-      std::unique_ptr<Botan::PKCS8_PrivateKey> pkcs8(
-         Botan::PKCS8::load_key(src, rng, static_cast<std::string>(password)));
-
-      if(pkcs8)
-         {
-         *key = new botan_privkey_struct(pkcs8.release());
-         return BOTAN_FFI_SUCCESS;
-         }
-      return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
-      });
-   }
-
-int botan_pubkey_load(botan_pubkey_t* key,
-                      const uint8_t bits[], size_t bits_len)
-   {
-   *key = nullptr;
-
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::DataSource_Memory src(bits, bits_len);
-      std::unique_ptr<Botan::Public_Key> pubkey(Botan::X509::load_key(src));
-
-      if(pubkey == nullptr)
-         return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
-
-      *key = new botan_pubkey_struct(pubkey.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_privkey_load_rsa(botan_privkey_t* key,
-                           botan_mp_t rsa_p, botan_mp_t rsa_q, botan_mp_t rsa_e)
-   {
-#if defined(BOTAN_HAS_RSA)
-   *key = nullptr;
-
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      *key = new botan_privkey_struct(new Botan::RSA_PrivateKey(safe_get(rsa_p),
-                                                                safe_get(rsa_q),
-                                                                safe_get(rsa_e)));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, rsa_p, rsa_q, rsa_e);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_load_rsa(botan_pubkey_t* key,
-                          botan_mp_t n, botan_mp_t e)
-   {
-#if defined(BOTAN_HAS_RSA)
-   *key = nullptr;
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      *key = new botan_pubkey_struct(new Botan::RSA_PublicKey(safe_get(n), safe_get(e)));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, n, e);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_load_dsa(botan_privkey_t* key,
-                           botan_mp_t p, botan_mp_t q, botan_mp_t g, botan_mp_t x)
-   {
-#if defined(BOTAN_HAS_DSA)
-   *key = nullptr;
-
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::Null_RNG null_rng;
-      Botan::DL_Group group(safe_get(p), safe_get(q), safe_get(g));
-      *key = new botan_privkey_struct(new Botan::DSA_PrivateKey(null_rng, group, safe_get(x)));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, p, q, g, x);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_load_dsa(botan_pubkey_t* key,
-                          botan_mp_t p, botan_mp_t q, botan_mp_t g, botan_mp_t y)
-   {
-#if defined(BOTAN_HAS_DSA)
-   *key = nullptr;
-
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::DL_Group group(safe_get(p), safe_get(q), safe_get(g));
-      *key = new botan_pubkey_struct(new Botan::DSA_PublicKey(group, safe_get(y)));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, p, q, g, y);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_load_elgamal(botan_pubkey_t* key,
-                              botan_mp_t p, botan_mp_t g, botan_mp_t y)
-   {
-#if defined(BOTAN_HAS_ELGAMAL)
-   *key = nullptr;
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::DL_Group group(safe_get(p), safe_get(g));
-      *key = new botan_pubkey_struct(new Botan::ElGamal_PublicKey(group, safe_get(y)));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, p, g, y);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_load_elgamal(botan_privkey_t* key,
-                               botan_mp_t p, botan_mp_t g, botan_mp_t x)
-   {
-#if defined(BOTAN_HAS_ELGAMAL)
-   *key = nullptr;
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::Null_RNG null_rng;
-      Botan::DL_Group group(safe_get(p), safe_get(g));
-      *key = new botan_privkey_struct(new Botan::ElGamal_PrivateKey(null_rng, group, safe_get(x)));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, p, g, x);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_load_ed25519(botan_privkey_t* key,
-                               const uint8_t privkey[32])
-   {
-#if defined(BOTAN_HAS_ED25519)
-   *key = nullptr;
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      const Botan::secure_vector<uint8_t> privkey_vec(privkey, privkey + 32);
-      *key = new botan_privkey_struct(new Botan::Ed25519_PrivateKey(privkey_vec));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, privkey);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_load_ed25519(botan_pubkey_t* key,
-                              const uint8_t pubkey[32])
-   {
-#if defined(BOTAN_HAS_ED25519)
-   *key = nullptr;
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      const std::vector<uint8_t> pubkey_vec(pubkey, pubkey + 32);
-      *key = new botan_pubkey_struct(new Botan::Ed25519_PublicKey(pubkey_vec));
-      return BOTAN_FFI_SUCCESS;
-      });
-#else
-   BOTAN_UNUSED(key, pubkey);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_ed25519_get_privkey(botan_privkey_t key,
-                                      uint8_t output[64])
-   {
-#if defined(BOTAN_HAS_ED25519)
-   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
-      if(Botan::Ed25519_PrivateKey* ed = dynamic_cast<Botan::Ed25519_PrivateKey*>(&k))
-         {
-         const Botan::secure_vector<uint8_t>& key = ed->get_private_key();
-         if(key.size() != 64)
-            return BOTAN_FFI_ERROR_INSUFFICIENT_BUFFER_SPACE;
-         Botan::copy_mem(output, key.data(), key.size());
-         return BOTAN_FFI_SUCCESS;
-         }
-      else
-         {
-         return BOTAN_FFI_ERROR_BAD_PARAMETER;
-         }
-      });
-#else
-   BOTAN_UNUSED(key, output);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_ed25519_get_pubkey(botan_pubkey_t key,
-                                    uint8_t output[32])
-   {
-#if defined(BOTAN_HAS_ED25519)
-   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
-      if(Botan::Ed25519_PublicKey* ed = dynamic_cast<Botan::Ed25519_PublicKey*>(&k))
-         {
-         const std::vector<uint8_t>& key = ed->get_public_key();
-         if(key.size() != 32)
-            return BOTAN_FFI_ERROR_INSUFFICIENT_BUFFER_SPACE;
-         Botan::copy_mem(output, key.data(), key.size());
-         return BOTAN_FFI_SUCCESS;
-         }
-      else
-         {
-         return BOTAN_FFI_ERROR_BAD_PARAMETER;
-         }
-      });
-#else
-   BOTAN_UNUSED(key, output);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_load_ecdsa(botan_pubkey_t* key,
-                                   const botan_mp_t public_x,
-                                   const botan_mp_t public_y,
-                                   const char* curve_name)
-   {
-#if defined(BOTAN_HAS_ECDSA)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::ECDSA_PublicKey> p_key;
-
-      int rc = pubkey_load_ec(p_key, safe_get(public_x), safe_get(public_y), curve_name);
-      if(rc == BOTAN_FFI_SUCCESS)
-         *key = new botan_pubkey_struct(p_key.release());
-
-      return rc;
-      });
-#else
-   BOTAN_UNUSED(key, public_x, public_y, curve_name);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_load_sm2(botan_pubkey_t* key,
-                          const botan_mp_t public_x,
-                          const botan_mp_t public_y,
-                          const char* curve_name)
-   {
-#if defined(BOTAN_HAS_SM2)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::SM2_Signature_PublicKey> p_key;
-      if(!pubkey_load_ec(p_key, safe_get(public_x), safe_get(public_y), curve_name))
-         {
-         *key = new botan_pubkey_struct(p_key.release());
-         return BOTAN_FFI_SUCCESS;
-         }
-      return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
-      });
-#else
-   BOTAN_UNUSED(key, public_x, public_y, curve_name);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_load_ecdh(botan_pubkey_t* key,
-                                   const botan_mp_t public_x,
-                                   const botan_mp_t public_y,
-                                   const char* curve_name)
-   {
-#if defined(BOTAN_HAS_ECDH)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::ECDH_PublicKey> p_key;
-      int rc = pubkey_load_ec(p_key, safe_get(public_x), safe_get(public_y), curve_name);
-
-      if(rc == BOTAN_FFI_SUCCESS)
-         *key = new botan_pubkey_struct(p_key.release());
-      return rc;
-      });
-#else
-   BOTAN_UNUSED(key, public_x, public_y, curve_name);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_load_ecdsa(botan_privkey_t* key,
-                          const botan_mp_t scalar,
-                          const char* curve_name)
-   {
-#if defined(BOTAN_HAS_ECDSA)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::ECDSA_PrivateKey> p_key;
-      int rc = privkey_load_ec(p_key, safe_get(scalar), curve_name);
-      if(rc == BOTAN_FFI_SUCCESS)
-         *key = new botan_privkey_struct(p_key.release());
-      return rc;
-      });
-#else
-   BOTAN_UNUSED(key, scalar, curve_name);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_load_sm2(botan_privkey_t* key,
-                           const botan_mp_t scalar,
-                           const char* curve_name)
-   {
-#if defined(BOTAN_HAS_SM2)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::SM2_Signature_PrivateKey> p_key;
-      int rc = privkey_load_ec(p_key, safe_get(scalar), curve_name);
-
-      if(rc == BOTAN_FFI_SUCCESS)
-         *key = new botan_privkey_struct(p_key.release());
-      return rc;
-      });
-#else
-   BOTAN_UNUSED(key, scalar, curve_name);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_privkey_load_ecdh(botan_privkey_t* key,
-                          const botan_mp_t scalar,
-                          const char* curve_name)
-   {
-#if defined(BOTAN_HAS_ECDH)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::ECDH_PrivateKey> p_key;
-      int rc = privkey_load_ec(p_key, safe_get(scalar), curve_name);
-      if(rc == BOTAN_FFI_SUCCESS)
-         *key = new botan_privkey_struct(p_key.release());
-      return rc;
-      });
-#else
-   BOTAN_UNUSED(key, scalar, curve_name);
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_pubkey_get_field(botan_mp_t output,
-                           botan_pubkey_t key,
-                           const char* field_name_cstr)
-   {
-   if(field_name_cstr == nullptr)
-      return BOTAN_FFI_ERROR_NULL_POINTER;
-
-   const std::string field_name(field_name_cstr);
-
-   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
-      safe_get(output) = pubkey_get_field(k, field_name);
-      });
-   }
-
-int botan_privkey_get_field(botan_mp_t output,
-                                      botan_privkey_t key,
-                                      const char* field_name_cstr)
-   {
-   if(field_name_cstr == nullptr)
-      return BOTAN_FFI_ERROR_NULL_POINTER;
-
-   const std::string field_name(field_name_cstr);
-
-   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
-      safe_get(output) = privkey_get_field(k, field_name);
-      });
-   }
-
-int botan_privkey_rsa_get_p(botan_mp_t p, botan_privkey_t key)
-   {
-   return botan_privkey_get_field(p, key, "p");
-   }
-
-int botan_privkey_rsa_get_q(botan_mp_t q, botan_privkey_t key)
-   {
-   return botan_privkey_get_field(q, key, "q");
-   }
-
-int botan_privkey_rsa_get_n(botan_mp_t n, botan_privkey_t key)
-   {
-   return botan_privkey_get_field(n, key, "n");
-   }
-
-int botan_privkey_rsa_get_e(botan_mp_t e, botan_privkey_t key)
-   {
-   return botan_privkey_get_field(e, key, "e");
-   }
-
-int botan_privkey_rsa_get_d(botan_mp_t d, botan_privkey_t key)
-   {
-   return botan_privkey_get_field(d, key, "d");
-   }
-
-int botan_pubkey_rsa_get_e(botan_mp_t e, botan_pubkey_t key)
-   {
-   return botan_pubkey_get_field(e, key, "e");
-   }
-
-int botan_pubkey_rsa_get_n(botan_mp_t n, botan_pubkey_t key)
-   {
-   return botan_pubkey_get_field(n, key, "n");
-   }
-
-int botan_privkey_dsa_get_x(botan_mp_t x, botan_privkey_t key)
-   {
-   return botan_privkey_get_field(x, key, "x");
-   }
-
-int botan_pubkey_dsa_get_p(botan_mp_t p, botan_pubkey_t key)
-   {
-   return botan_pubkey_get_field(p, key, "p");
-   }
-int botan_pubkey_dsa_get_q(botan_mp_t q, botan_pubkey_t key)
-   {
-   return botan_pubkey_get_field(q, key, "q");
-   }
-int botan_pubkey_dsa_get_g(botan_mp_t g, botan_pubkey_t key)
-   {
-   return botan_pubkey_get_field(g, key, "g");
-   }
-int botan_pubkey_dsa_get_y(botan_mp_t y, botan_pubkey_t key)
-   {
-   return botan_pubkey_get_field(y, key, "y");
-   }
-
-int botan_privkey_destroy(botan_privkey_t key)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(key);
-   }
-
-int botan_pubkey_destroy(botan_pubkey_t key)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(key);
-   }
-
-int botan_privkey_export_pubkey(botan_pubkey_t* pubout, botan_privkey_t key_obj)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      std::unique_ptr<Botan::Public_Key>
-         pubkey(Botan::X509::load_key(Botan::X509::BER_encode(safe_get(key_obj))));
-
-      *pubout = new botan_pubkey_struct(pubkey.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_pubkey_algo_name(botan_pubkey_t key, char out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::Public_Key, key, k, { return write_str_output(out, out_len, k.algo_name()); });
-   }
-
-int botan_pubkey_check_key(botan_pubkey_t key, botan_rng_t rng, uint32_t flags)
-   {
-   const bool strong = (flags & BOTAN_CHECK_KEY_EXPENSIVE_TESTS);
-
-   return BOTAN_FFI_DO(Botan::Public_Key, key, k,
-                       { return (k.check_key(safe_get(rng), strong) == true) ? 0 : -1; });
-   }
-
-int botan_privkey_check_key(botan_privkey_t key, botan_rng_t rng, uint32_t flags)
-   {
-   const bool strong = (flags & BOTAN_CHECK_KEY_EXPENSIVE_TESTS);
-   return BOTAN_FFI_DO(Botan::Private_Key, key, k,
-                       { return (k.check_key(safe_get(rng), strong) == true) ? 0 : -1; });
-   }
-
-int botan_pubkey_export(botan_pubkey_t key, uint8_t out[], size_t* out_len, uint32_t flags)
-   {
-   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
-      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
-         return write_vec_output(out, out_len, Botan::X509::BER_encode(k));
-      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
-         return write_str_output(out, out_len, Botan::X509::PEM_encode(k));
-      else
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-      });
-   }
-
-int botan_privkey_export(botan_privkey_t key, uint8_t out[], size_t* out_len, uint32_t flags)
-   {
-   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
-      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
-         return write_vec_output(out, out_len, Botan::PKCS8::BER_encode(k));
-      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
-         return write_str_output(out, out_len, Botan::PKCS8::PEM_encode(k));
-      else
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-      });
-   }
-
-int botan_privkey_export_encrypted(botan_privkey_t key,
-                                   uint8_t out[], size_t* out_len,
-                                   botan_rng_t rng_obj,
-                                   const char* pass,
-                                   const char* /*ignored - pbe*/,
-                                   uint32_t flags)
-   {
-   return botan_privkey_export_encrypted_pbkdf_iter(key, out, out_len, rng_obj, pass, 100000, nullptr, nullptr, flags);
-   }
-
-int botan_privkey_export_encrypted_pbkdf_msec(botan_privkey_t key,
-                                              uint8_t out[], size_t* out_len,
-                                              botan_rng_t rng_obj,
-                                              const char* pass,
-                                              uint32_t pbkdf_msec,
-                                              size_t* pbkdf_iters_out,
-                                              const char* maybe_cipher,
-                                              const char* maybe_pbkdf_hash,
-                                              uint32_t flags)
-   {
-   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
-      const std::chrono::milliseconds pbkdf_time(pbkdf_msec);
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-
-      std::string cipher;
-      if(maybe_cipher)
-         {
-         cipher = maybe_cipher;
-         }
-
-      std::string pbkdf_hash;
-      if(maybe_pbkdf_hash)
-         {
-         pbkdf_hash = maybe_pbkdf_hash;
-         }
-
-      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
-         {
-         return write_vec_output(out, out_len,
-                                 Botan::PKCS8::BER_encode_encrypted_pbkdf_msec(k, rng, pass, pbkdf_time, pbkdf_iters_out, cipher, pbkdf_hash));
-         }
-      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
-         {
-         return write_str_output(out, out_len,
-                                 Botan::PKCS8::PEM_encode_encrypted_pbkdf_msec(k, rng, pass, pbkdf_time, pbkdf_iters_out, cipher, pbkdf_hash));
-         }
-      else
-         {
-         return -2;
-         }
-      });
-   }
-
-int botan_privkey_export_encrypted_pbkdf_iter(botan_privkey_t key,
-                                              uint8_t out[], size_t* out_len,
-                                              botan_rng_t rng_obj,
-                                              const char* pass,
-                                              size_t pbkdf_iter,
-                                              const char* maybe_cipher,
-                                              const char* maybe_pbkdf_hash,
-                                              uint32_t flags)
-   {
-   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-
-      std::string cipher;
-      if(maybe_cipher)
-         {
-         cipher = maybe_cipher;
-         }
-
-      std::string pbkdf_hash;
-      if(maybe_pbkdf_hash)
-         {
-         pbkdf_hash = maybe_pbkdf_hash;
-         }
-
-      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
-         {
-         return write_vec_output(out, out_len,
-                                 Botan::PKCS8::BER_encode_encrypted_pbkdf_iter(k, rng, pass, pbkdf_iter, cipher, pbkdf_hash));
-         }
-      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
-         {
-         return write_str_output(out, out_len,
-                                 Botan::PKCS8::PEM_encode_encrypted_pbkdf_iter(k, rng, pass, pbkdf_iter, cipher, pbkdf_hash));
-         }
-      else
-         {
-         return -2;
-         }
-      });
-   }
-
-int botan_pubkey_estimated_strength(botan_pubkey_t key, size_t* estimate)
-   {
-   return BOTAN_FFI_DO(Botan::Public_Key, key, k, { *estimate = k.estimated_strength(); });
-   }
-
-int botan_pubkey_fingerprint(botan_pubkey_t key, const char* hash_fn,
-                             uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
-      std::unique_ptr<Botan::HashFunction> h(Botan::HashFunction::create(hash_fn));
-      return write_vec_output(out, out_len, h->process(k.public_key_bits()));
-      });
-   }
-
-int botan_pk_op_encrypt_create(botan_pk_op_encrypt_t* op,
-                               botan_pubkey_t key_obj,
-                               const char* padding,
-                               uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_NONNULL(op);
-
-      *op = nullptr;
-
-      if(flags != 0)
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-
-      std::unique_ptr<Botan::PK_Encryptor> pk(new Botan::PK_Encryptor_EME(safe_get(key_obj), Botan::system_rng(), padding));
-      *op = new botan_pk_op_encrypt_struct(pk.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_pk_op_encrypt_destroy(botan_pk_op_encrypt_t op)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(op);
-   }
-
-int botan_pk_op_encrypt(botan_pk_op_encrypt_t op,
-                        botan_rng_t rng_obj,
-                        uint8_t out[], size_t* out_len,
-                        const uint8_t plaintext[], size_t plaintext_len)
-   {
-   return BOTAN_FFI_DO(Botan::PK_Encryptor, op, o, {
-      return write_vec_output(out, out_len, o.encrypt(plaintext, plaintext_len, safe_get(rng_obj)));
-      });
-   }
-
-/*
-* Public Key Decryption
-*/
-int botan_pk_op_decrypt_create(botan_pk_op_decrypt_t* op,
-                               botan_privkey_t key_obj,
-                               const char* padding,
-                               uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_NONNULL(op);
-
-      *op = nullptr;
-
-      if(flags != 0)
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-
-      std::unique_ptr<Botan::PK_Decryptor> pk(new Botan::PK_Decryptor_EME(safe_get(key_obj), Botan::system_rng(), padding));
-      *op = new botan_pk_op_decrypt_struct(pk.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_pk_op_decrypt_destroy(botan_pk_op_decrypt_t op)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(op);
-   }
-
-int botan_pk_op_decrypt(botan_pk_op_decrypt_t op,
-                        uint8_t out[], size_t* out_len,
-                        const uint8_t ciphertext[], size_t ciphertext_len)
-   {
-   return BOTAN_FFI_DO(Botan::PK_Decryptor, op, o, {
-      return write_vec_output(out, out_len, o.decrypt(ciphertext, ciphertext_len));
-      });
-   }
-
-/*
-* Signature Generation
-*/
-int botan_pk_op_sign_create(botan_pk_op_sign_t* op,
-                            botan_privkey_t key_obj,
-                            const char* hash,
-                            uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_NONNULL(op);
-
-      *op = nullptr;
-
-      if(flags != 0)
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-
-      std::unique_ptr<Botan::PK_Signer> pk(new Botan::PK_Signer(safe_get(key_obj),Botan::system_rng(),  hash));
-      *op = new botan_pk_op_sign_struct(pk.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_pk_op_sign_destroy(botan_pk_op_sign_t op)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(op);
-   }
-
-int botan_pk_op_sign_update(botan_pk_op_sign_t op, const uint8_t in[], size_t in_len)
-   {
-   return BOTAN_FFI_DO(Botan::PK_Signer, op, o, { o.update(in, in_len); });
-   }
-
-int botan_pk_op_sign_finish(botan_pk_op_sign_t op, botan_rng_t rng_obj, uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::PK_Signer, op, o, {
-      return write_vec_output(out, out_len, o.signature(safe_get(rng_obj)));
-      });
-   }
-
-int botan_pk_op_verify_create(botan_pk_op_verify_t* op,
-                              botan_pubkey_t key_obj,
-                              const char* hash,
-                              uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_NONNULL(op);
-
-      if(flags != 0)
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-
-      std::unique_ptr<Botan::PK_Verifier> pk(new Botan::PK_Verifier(safe_get(key_obj), hash));
-      *op = new botan_pk_op_verify_struct(pk.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_pk_op_verify_destroy(botan_pk_op_verify_t op)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(op);
-   }
-
-int botan_pk_op_verify_update(botan_pk_op_verify_t op, const uint8_t in[], size_t in_len)
-   {
-   return BOTAN_FFI_DO(Botan::PK_Verifier, op, o, { o.update(in, in_len); });
-   }
-
-int botan_pk_op_verify_finish(botan_pk_op_verify_t op, const uint8_t sig[], size_t sig_len)
-   {
-   return BOTAN_FFI_DO(Botan::PK_Verifier, op, o, {
-      const bool legit = o.check_signature(sig, sig_len);
-
-      if(legit)
-         return BOTAN_FFI_SUCCESS;
-      else
-         return BOTAN_FFI_ERROR_INVALID_INPUT;
-      });
-   }
-
-int botan_pk_op_key_agreement_create(botan_pk_op_ka_t* op,
-                                     botan_privkey_t key_obj,
-                                     const char* kdf,
-                                     uint32_t flags)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      BOTAN_ASSERT_NONNULL(op);
-
-      *op = nullptr;
-
-      if(flags != 0)
-         return BOTAN_FFI_ERROR_BAD_FLAG;
-
-      std::unique_ptr<Botan::PK_Key_Agreement> pk(new Botan::PK_Key_Agreement(safe_get(key_obj), Botan::system_rng(), kdf));
-      *op = new botan_pk_op_ka_struct(pk.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_pk_op_key_agreement_destroy(botan_pk_op_ka_t op)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(op);
-   }
-
-int botan_pk_op_key_agreement_export_public(botan_privkey_t key,
-                                            uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
-      if(auto kak = dynamic_cast<const Botan::PK_Key_Agreement_Key*>(&k))
-         return write_vec_output(out, out_len, kak->public_value());
-      return BOTAN_FFI_ERROR_BAD_FLAG;
-      });
-   }
-
-int botan_pk_op_key_agreement(botan_pk_op_ka_t op,
-                              uint8_t out[], size_t* out_len,
-                              const uint8_t other_key[], size_t other_key_len,
-                              const uint8_t salt[], size_t salt_len)
-   {
-   return BOTAN_FFI_DO(Botan::PK_Key_Agreement, op, o, {
-      auto k = o.derive_key(*out_len, other_key, other_key_len, salt, salt_len).bits_of();
-      return write_vec_output(out, out_len, k);
-      });
-   }
-
-int botan_x509_cert_load_file(botan_x509_cert_t* cert_obj, const char* cert_path)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(!cert_obj || !cert_path)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-#if defined(BOTAN_TARGET_OS_HAS_FILESYSTEM)
-      std::unique_ptr<Botan::X509_Certificate> c(new Botan::X509_Certificate(cert_path));
-      *cert_obj = new botan_x509_cert_struct(c.release());
-      return BOTAN_FFI_SUCCESS;
-#else
-      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-      });
-   }
-
-int botan_x509_cert_load(botan_x509_cert_t* cert_obj, const uint8_t cert_bits[], size_t cert_bits_len)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(!cert_obj || !cert_bits)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      Botan::DataSource_Memory bits(cert_bits, cert_bits_len);
-
-      std::unique_ptr<Botan::X509_Certificate> c(new Botan::X509_Certificate(bits));
-      *cert_obj = new botan_x509_cert_struct(c.release());
-      return BOTAN_FFI_SUCCESS;
-      });
-   }
-
-int botan_x509_cert_destroy(botan_x509_cert_t cert)
-   {
-   return BOTAN_FFI_CHECKED_DELETE(cert);
-   }
-
-int botan_x509_cert_get_time_starts(botan_x509_cert_t cert, char out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.start_time()); });
-   }
-
-int botan_x509_cert_get_time_expires(botan_x509_cert_t cert, char out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.end_time()); });
-   }
-
-int botan_x509_cert_get_serial_number(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.serial_number()); });
-   }
-
-int botan_x509_cert_get_fingerprint(botan_x509_cert_t cert, const char* hash, uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.fingerprint(hash)); });
-   }
-
-int botan_x509_cert_get_authority_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.authority_key_id()); });
-   }
-
-int botan_x509_cert_get_subject_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.subject_key_id()); });
-   }
-
-int botan_x509_cert_get_public_key_bits(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.subject_public_key_bits()); });
-   }
-
-
-/*
-int botan_x509_cert_path_verify(botan_x509_cert_t cert, const char* dir)
-{
-}
-*/
-
-int botan_x509_cert_get_public_key(botan_x509_cert_t cert, botan_pubkey_t* key)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      if(key == nullptr)
-         return BOTAN_FFI_ERROR_NULL_POINTER;
-
-      *key = nullptr;
-
-#if defined(BOTAN_HAS_RSA)
-      std::unique_ptr<Botan::Public_Key> publicKey(safe_get(cert).subject_public_key());
-      *key = new botan_pubkey_struct(publicKey.release());
-      return BOTAN_FFI_SUCCESS;
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-      });
-   }
-
-int botan_x509_cert_get_issuer_dn(botan_x509_cert_t cert,
-                                  const char* key, size_t index,
-                                  uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.issuer_info(key).at(index)); });
-   }
-
-int botan_x509_cert_get_subject_dn(botan_x509_cert_t cert,
-                                   const char* key, size_t index,
-                                   uint8_t out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.subject_info(key).at(index)); });
-   }
-
-int botan_x509_cert_to_string(botan_x509_cert_t cert, char out[], size_t* out_len)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.to_string()); });
-   }
-
-int botan_x509_cert_allowed_usage(botan_x509_cert_t cert, unsigned int key_usage)
-   {
-   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, {
-      const Botan::Key_Constraints k = static_cast<Botan::Key_Constraints>(key_usage);
-      if(c.allowed_usage(k))
-         return BOTAN_FFI_SUCCESS;
-      return 1;
-      });
-   }
-
-int botan_pkcs_hash_id(const char* hash_name, uint8_t pkcs_id[], size_t* pkcs_id_len)
-   {
-#if defined(BOTAN_HAS_HASH_ID)
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      const std::vector<uint8_t> hash_id = Botan::pkcs_hash_id(hash_name);
-      return write_output(pkcs_id, pkcs_id_len, hash_id.data(), hash_id.size());
-      });
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-   }
-
-int botan_mceies_decrypt(botan_privkey_t mce_key_obj,
-                         const char* aead,
-                         const uint8_t ct[], size_t ct_len,
-                         const uint8_t ad[], size_t ad_len,
-                         uint8_t out[], size_t* out_len)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::Private_Key& key = safe_get(mce_key_obj);
-
-#if defined(BOTAN_HAS_MCELIECE) && defined(BOTAN_HAS_MCEIES)
-      Botan::McEliece_PrivateKey* mce = dynamic_cast<Botan::McEliece_PrivateKey*>(&key);
-      if(!mce)
-         return BOTAN_FFI_ERROR_BAD_PARAMETER;
-
-      const Botan::secure_vector<uint8_t> pt = mceies_decrypt(*mce, ct, ct_len, ad, ad_len, aead);
-      return write_vec_output(out, out_len, pt);
-#else
-      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-      });
-   }
-
-int botan_mceies_encrypt(botan_pubkey_t mce_key_obj,
-                         botan_rng_t rng_obj,
-                         const char* aead,
-                         const uint8_t pt[], size_t pt_len,
-                         const uint8_t ad[], size_t ad_len,
-                         uint8_t out[], size_t* out_len)
-   {
-   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
-      Botan::Public_Key& key = safe_get(mce_key_obj);
-      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
-
-#if defined(BOTAN_HAS_MCELIECE) && defined(BOTAN_HAS_MCEIES)
-      Botan::McEliece_PublicKey* mce = dynamic_cast<Botan::McEliece_PublicKey*>(&key);
-      if(!mce)
-         return BOTAN_FFI_ERROR_BAD_PARAMETER;
-
-      Botan::secure_vector<uint8_t> ct = mceies_encrypt(*mce, pt, pt_len, ad, ad_len, rng, aead);
-      return write_vec_output(out, out_len, ct);
-#else
-      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-      });
-   }
-
-int botan_key_wrap3394( uint8_t key[], size_t key_len,
-                        uint8_t kek[], size_t kek_len,
-                        uint8_t wrapped_key[], size_t *wrapped_key_len)
-{
-#if defined(BOTAN_HAS_RFC3394_KEYWRAP)
-   try
-      {
-         const Botan::SymmetricKey kek_sym(kek, kek_len);
-         const Botan::secure_vector<uint8_t> key_pt(key, key + key_len);
-         const Botan::secure_vector<uint8_t> key_ct = Botan::rfc3394_keywrap(key_pt, kek_sym);
-         return write_vec_output(wrapped_key, wrapped_key_len, key_ct);
-      }
-   catch(std::exception &e)
-      {
-         return ffi_error_exception_thrown(e.what());
-      }
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-}
-
-int botan_key_unwrap3394(  uint8_t wrapped_key[], size_t wrapped_key_len,
-                           uint8_t kek[], size_t kek_len,
-                           uint8_t key[], size_t *key_len)
-{
-#if defined(BOTAN_HAS_RFC3394_KEYWRAP)
-   try
-      {
-         const Botan::SymmetricKey kek_sym(kek, kek_len);
-         const Botan::secure_vector<uint8_t> key_ct(wrapped_key, wrapped_key + wrapped_key_len);
-         const Botan::secure_vector<uint8_t> key_pt = Botan::rfc3394_keyunwrap(key_ct, kek_sym);
-         return write_vec_output(key, key_len, key_pt);
-      }
-   catch(std::exception &e)
-      {
-         return ffi_error_exception_thrown(e.what());
-      }
-#else
-   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
-#endif
-}
-
-/*
-int botan_tls_channel_init_client(botan_tls_channel_t* channel,
-                                  botan_tls_channel_output_fn output_fn,
-                                  botan_tls_channel_data_cb data_cb,
-                                  botan_tls_channel_alert_cb alert_cb,
-                                  botan_tls_channel_session_established session_cb,
-                                  const char* server_name)
-   {
-
-   }
-*/
-
 }
 
diff --git a/src/lib/ffi/ffi.h b/src/lib/ffi/ffi.h
index e56ad5629..45cce37d2 100644
--- a/src/lib/ffi/ffi.h
+++ b/src/lib/ffi/ffi.h
@@ -873,22 +873,22 @@ BOTAN_DLL int botan_pubkey_ed25519_get_pubkey(botan_pubkey_t key,
 * Algorithm specific key operations: ECDSA and ECDH
 */
 BOTAN_DLL int botan_privkey_load_ecdsa(botan_privkey_t* key,
-                                    const botan_mp_t scalar,
-                                    const char* curve_name);
+                                       const botan_mp_t scalar,
+                                       const char* curve_name);
 
 BOTAN_DLL int botan_pubkey_load_ecdsa(botan_pubkey_t* key,
-                                   const botan_mp_t public_x,
-                                   const botan_mp_t public_y,
-                                   const char* curve_name);
+                                      const botan_mp_t public_x,
+                                      const botan_mp_t public_y,
+                                      const char* curve_name);
 
 BOTAN_DLL int botan_pubkey_load_ecdh(botan_pubkey_t* key,
-                                   const botan_mp_t public_x,
-                                   const botan_mp_t public_y,
-                                   const char* curve_name);
+                                     const botan_mp_t public_x,
+                                     const botan_mp_t public_y,
+                                     const char* curve_name);
 
 BOTAN_DLL int botan_privkey_load_ecdh(botan_privkey_t* key,
-                                    const botan_mp_t scalar,
-                                    const char* curve_name);
+                                      const botan_mp_t scalar,
+                                      const char* curve_name);
 
 BOTAN_DLL int botan_pubkey_load_sm2(botan_pubkey_t* key,
                                     const botan_mp_t public_x,
@@ -1023,9 +1023,6 @@ BOTAN_DLL int botan_x509_cert_get_serial_number(botan_x509_cert_t cert, uint8_t
 BOTAN_DLL int botan_x509_cert_get_authority_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len);
 BOTAN_DLL int botan_x509_cert_get_subject_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len);
 
-BOTAN_DLL int botan_x509_cert_path_verify(botan_x509_cert_t cert,
-                                          const char* ca_dir);
-
 BOTAN_DLL int botan_x509_cert_get_public_key_bits(botan_x509_cert_t cert,
                                                   uint8_t out[], size_t* out_len);
 
diff --git a/src/lib/ffi/ffi_block.cpp b/src/lib/ffi/ffi_block.cpp
new file mode 100644
index 000000000..96a352877
--- /dev/null
+++ b/src/lib/ffi/ffi_block.cpp
@@ -0,0 +1,81 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/block_cipher.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_block_cipher_struct, Botan::BlockCipher, 0x64C29716);
+
+int botan_block_cipher_init(botan_block_cipher_t* bc, const char* bc_name)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(bc == nullptr || bc_name == nullptr || *bc_name == 0)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      *bc = nullptr;
+
+      std::unique_ptr<Botan::BlockCipher> cipher(Botan::BlockCipher::create(bc_name));
+      if(cipher == nullptr)
+         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+
+      *bc = new botan_block_cipher_struct(cipher.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+/**
+* Destroy a block cipher object
+*/
+int botan_block_cipher_destroy(botan_block_cipher_t bc)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(bc);
+   }
+
+int botan_block_cipher_clear(botan_block_cipher_t bc)
+   {
+   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.clear(); });
+   }
+
+/**
+* Set the key for a block cipher instance
+*/
+int botan_block_cipher_set_key(botan_block_cipher_t bc,
+                               const uint8_t key[], size_t len)
+   {
+   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.set_key(key, len); });
+   }
+
+/**
+* Return the positive block size of this block cipher, or negative to
+* indicate an error
+*/
+int botan_block_cipher_block_size(botan_block_cipher_t bc)
+   {
+   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { return b.block_size(); });
+   }
+
+int botan_block_cipher_encrypt_blocks(botan_block_cipher_t bc,
+                                      const uint8_t in[],
+                                      uint8_t out[],
+                                      size_t blocks)
+   {
+   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.encrypt_n(in, out, blocks); });
+   }
+
+int botan_block_cipher_decrypt_blocks(botan_block_cipher_t bc,
+                                      const uint8_t in[],
+                                      uint8_t out[],
+                                      size_t blocks)
+   {
+   return BOTAN_FFI_DO(Botan::BlockCipher, bc, b, { b.decrypt_n(in, out, blocks); });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_cert.cpp b/src/lib/ffi/ffi_cert.cpp
new file mode 100644
index 000000000..2ac9c69af
--- /dev/null
+++ b/src/lib/ffi/ffi_cert.cpp
@@ -0,0 +1,136 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/internal/ffi_pkey.h>
+#include <botan/x509cert.h>
+#include <botan/data_src.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_x509_cert_struct, Botan::X509_Certificate, 0x8F628937);
+
+int botan_x509_cert_load_file(botan_x509_cert_t* cert_obj, const char* cert_path)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(!cert_obj || !cert_path)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+#if defined(BOTAN_TARGET_OS_HAS_FILESYSTEM)
+      std::unique_ptr<Botan::X509_Certificate> c(new Botan::X509_Certificate(cert_path));
+      *cert_obj = new botan_x509_cert_struct(c.release());
+      return BOTAN_FFI_SUCCESS;
+#else
+      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+      });
+   }
+
+int botan_x509_cert_load(botan_x509_cert_t* cert_obj, const uint8_t cert_bits[], size_t cert_bits_len)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(!cert_obj || !cert_bits)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      Botan::DataSource_Memory bits(cert_bits, cert_bits_len);
+
+      std::unique_ptr<Botan::X509_Certificate> c(new Botan::X509_Certificate(bits));
+      *cert_obj = new botan_x509_cert_struct(c.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_x509_cert_get_public_key(botan_x509_cert_t cert, botan_pubkey_t* key)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(key == nullptr)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      *key = nullptr;
+
+#if defined(BOTAN_HAS_RSA)
+      std::unique_ptr<Botan::Public_Key> publicKey(safe_get(cert).subject_public_key());
+      *key = new botan_pubkey_struct(publicKey.release());
+      return BOTAN_FFI_SUCCESS;
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+      });
+   }
+
+int botan_x509_cert_get_issuer_dn(botan_x509_cert_t cert,
+                                  const char* key, size_t index,
+                                  uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.issuer_info(key).at(index)); });
+   }
+
+int botan_x509_cert_get_subject_dn(botan_x509_cert_t cert,
+                                   const char* key, size_t index,
+                                   uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.subject_info(key).at(index)); });
+   }
+
+int botan_x509_cert_to_string(botan_x509_cert_t cert, char out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.to_string()); });
+   }
+
+int botan_x509_cert_allowed_usage(botan_x509_cert_t cert, unsigned int key_usage)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, {
+      const Botan::Key_Constraints k = static_cast<Botan::Key_Constraints>(key_usage);
+      if(c.allowed_usage(k))
+         return BOTAN_FFI_SUCCESS;
+      return 1;
+      });
+   }
+
+int botan_x509_cert_destroy(botan_x509_cert_t cert)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(cert);
+   }
+
+int botan_x509_cert_get_time_starts(botan_x509_cert_t cert, char out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.start_time()); });
+   }
+
+int botan_x509_cert_get_time_expires(botan_x509_cert_t cert, char out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.end_time()); });
+   }
+
+int botan_x509_cert_get_serial_number(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.serial_number()); });
+   }
+
+int botan_x509_cert_get_fingerprint(botan_x509_cert_t cert, const char* hash, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_str_output(out, out_len, c.fingerprint(hash)); });
+   }
+
+int botan_x509_cert_get_authority_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.authority_key_id()); });
+   }
+
+int botan_x509_cert_get_subject_key_id(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.subject_key_id()); });
+   }
+
+int botan_x509_cert_get_public_key_bits(botan_x509_cert_t cert, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::X509_Certificate, cert, c, { return write_vec_output(out, out_len, c.subject_public_key_bits()); });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_cipher.cpp b/src/lib/ffi/ffi_cipher.cpp
new file mode 100644
index 000000000..6bb45dec8
--- /dev/null
+++ b/src/lib/ffi/ffi_cipher.cpp
@@ -0,0 +1,196 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/aead.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+struct botan_cipher_struct : public botan_struct<Botan::Cipher_Mode, 0xB4A2BF9C>
+   {
+   explicit botan_cipher_struct(Botan::Cipher_Mode* x) : botan_struct(x) {}
+   Botan::secure_vector<uint8_t> m_buf;
+   };
+
+int botan_cipher_init(botan_cipher_t* cipher, const char* cipher_name, uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      const bool encrypt_p = ((flags & BOTAN_CIPHER_INIT_FLAG_MASK_DIRECTION) == BOTAN_CIPHER_INIT_FLAG_ENCRYPT);
+      const Botan::Cipher_Dir dir = encrypt_p ? Botan::ENCRYPTION : Botan::DECRYPTION;
+      std::unique_ptr<Botan::Cipher_Mode> mode(Botan::get_cipher_mode(cipher_name, dir));
+      if(!mode)
+         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+      *cipher = new botan_cipher_struct(mode.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_cipher_destroy(botan_cipher_t cipher)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(cipher);
+   }
+
+int botan_cipher_clear(botan_cipher_t cipher)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { c.clear(); });
+   }
+
+int botan_cipher_query_keylen(botan_cipher_t cipher,
+                              size_t* out_minimum_keylength,
+                              size_t* out_maximum_keylength)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, {
+      *out_minimum_keylength = c.key_spec().minimum_keylength();
+      *out_maximum_keylength = c.key_spec().maximum_keylength();
+      });
+   }
+
+int botan_cipher_set_key(botan_cipher_t cipher,
+                         const uint8_t* key, size_t key_len)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { c.set_key(key, key_len); });
+   }
+
+int botan_cipher_start(botan_cipher_t cipher_obj,
+                       const uint8_t* nonce, size_t nonce_len)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::Cipher_Mode& cipher = safe_get(cipher_obj);
+      cipher.start(nonce, nonce_len);
+      cipher_obj->m_buf.reserve(cipher.update_granularity());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_cipher_update(botan_cipher_t cipher_obj,
+                        uint32_t flags,
+                        uint8_t output_ptr[],
+                        size_t orig_output_size,
+                        size_t* output_written,
+                        const uint8_t input_ptr[],
+                        size_t orig_input_size,
+                        size_t* input_consumed)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+
+      size_t input_size = orig_input_size;
+      size_t output_size = orig_output_size;
+      const uint8_t* input = input_ptr;
+      uint8_t* output = output_ptr;
+
+      using namespace Botan;
+      Cipher_Mode& cipher = safe_get(cipher_obj);
+      secure_vector<uint8_t>& mbuf = cipher_obj->m_buf;
+
+      const bool final_input = (flags & BOTAN_CIPHER_UPDATE_FLAG_FINAL);
+
+      if(final_input)
+         {
+         mbuf.assign(input, input + input_size);
+         *input_consumed = input_size;
+         *output_written = 0;
+
+         try
+            {
+            cipher.finish(mbuf);
+            }
+         catch(Integrity_Failure& e)
+            {
+            return BOTAN_FFI_ERROR_BAD_MAC;
+            }
+
+         *output_written = mbuf.size();
+
+         if(mbuf.size() <= output_size)
+            {
+            copy_mem(output, mbuf.data(), mbuf.size());
+            mbuf.clear();
+            return BOTAN_FFI_SUCCESS;
+            }
+
+         return -1;
+         }
+
+      if(input_size == 0)
+         {
+         // Currently must take entire buffer in this case
+         *output_written = mbuf.size();
+         if(output_size >= mbuf.size())
+            {
+            copy_mem(output, mbuf.data(), mbuf.size());
+            mbuf.clear();
+            return BOTAN_FFI_SUCCESS;
+            }
+
+         return -1;
+         }
+
+      const size_t ud = cipher.update_granularity();
+      BOTAN_ASSERT(cipher.update_granularity() > cipher.minimum_final_size(), "logic error");
+
+      mbuf.resize(ud);
+      size_t taken = 0, written = 0;
+
+      while(input_size >= ud && output_size >= ud)
+         {
+         copy_mem(mbuf.data(), input, ud);
+         cipher.update(mbuf);
+
+         input_size -= ud;
+         copy_mem(output, mbuf.data(), ud);
+         input += ud;
+         taken += ud;
+
+         output_size -= ud;
+         output += ud;
+         written += ud;
+         }
+
+      *output_written = written;
+      *input_consumed = taken;
+
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_cipher_set_associated_data(botan_cipher_t cipher,
+                                     const uint8_t* ad,
+                                     size_t ad_len)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, {
+      if(Botan::AEAD_Mode* aead = dynamic_cast<Botan::AEAD_Mode*>(&c))
+         {
+         aead->set_associated_data(ad, ad_len);
+         return BOTAN_FFI_SUCCESS;
+         }
+      return BOTAN_FFI_ERROR_BAD_PARAMETER;
+      });
+   }
+
+int botan_cipher_valid_nonce_length(botan_cipher_t cipher, size_t nl)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { return c.valid_nonce_length(nl) ? 1 : 0; });
+   }
+
+int botan_cipher_get_default_nonce_length(botan_cipher_t cipher, size_t* nl)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *nl = c.default_nonce_length(); });
+   }
+
+int botan_cipher_get_update_granularity(botan_cipher_t cipher, size_t* ug)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *ug = c.update_granularity(); });
+   }
+
+int botan_cipher_get_tag_length(botan_cipher_t cipher, size_t* tl)
+   {
+   return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *tl = c.tag_size(); });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_hash.cpp b/src/lib/ffi/ffi_hash.cpp
new file mode 100644
index 000000000..58fb1d38f
--- /dev/null
+++ b/src/lib/ffi/ffi_hash.cpp
@@ -0,0 +1,70 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/hash.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_hash_struct, Botan::HashFunction, 0x1F0A4F84);
+
+int botan_hash_init(botan_hash_t* hash, const char* hash_name, uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(hash == nullptr || hash_name == nullptr || *hash_name == 0)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+      if(flags != 0)
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+
+      std::unique_ptr<Botan::HashFunction> h = Botan::HashFunction::create(hash_name);
+      if(h == nullptr)
+         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+
+      *hash = new botan_hash_struct(h.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_hash_destroy(botan_hash_t hash)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(hash);
+   }
+
+int botan_hash_output_length(botan_hash_t hash, size_t* out)
+   {
+   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { *out = h.output_length(); });
+   }
+
+int botan_hash_block_size(botan_hash_t hash, size_t* out)
+   {
+   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { *out = h.hash_block_size(); });
+   }
+
+int botan_hash_clear(botan_hash_t hash)
+   {
+   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { h.clear(); });
+   }
+
+int botan_hash_update(botan_hash_t hash, const uint8_t* buf, size_t len)
+   {
+   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { h.update(buf, len); });
+   }
+
+int botan_hash_final(botan_hash_t hash, uint8_t out[])
+   {
+   return BOTAN_FFI_DO(Botan::HashFunction, hash, h, { h.final(out); });
+   }
+
+int botan_hash_copy_state(botan_hash_t* dest, const botan_hash_t source)
+   {
+   return BOTAN_FFI_DO(Botan::HashFunction, source, src, {
+      *dest = new botan_hash_struct(src.copy_state().release()); });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_kdf.cpp b/src/lib/ffi/ffi_kdf.cpp
new file mode 100644
index 000000000..058c4c655
--- /dev/null
+++ b/src/lib/ffi/ffi_kdf.cpp
@@ -0,0 +1,98 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/internal/ffi_rng.h>
+#include <botan/pbkdf.h>
+#include <botan/kdf.h>
+
+#if defined(BOTAN_HAS_BCRYPT)
+  #include <botan/bcrypt.h>
+#endif
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+int botan_pbkdf(const char* pbkdf_algo, uint8_t out[], size_t out_len,
+                const char* pass, const uint8_t salt[], size_t salt_len,
+                size_t iterations)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::PBKDF> pbkdf(Botan::get_pbkdf(pbkdf_algo));
+      pbkdf->pbkdf_iterations(out, out_len, pass, salt, salt_len, iterations);
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pbkdf_timed(const char* pbkdf_algo,
+                      uint8_t out[], size_t out_len,
+                      const char* password,
+                      const uint8_t salt[], size_t salt_len,
+                      size_t ms_to_run,
+                      size_t* iterations_used)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::PBKDF> pbkdf(Botan::get_pbkdf(pbkdf_algo));
+      pbkdf->pbkdf_timed(out, out_len, password, salt, salt_len,
+                         std::chrono::milliseconds(ms_to_run),
+                         *iterations_used);
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_kdf(const char* kdf_algo,
+              uint8_t out[], size_t out_len,
+              const uint8_t secret[], size_t secret_len,
+              const uint8_t salt[], size_t salt_len,
+              const uint8_t label[], size_t label_len)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::KDF> kdf(Botan::get_kdf(kdf_algo));
+      kdf->kdf(out, out_len, secret, secret_len, salt, salt_len, label, label_len);
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_bcrypt_generate(uint8_t* out, size_t* out_len,
+                          const char* pass,
+                          botan_rng_t rng_obj, size_t wf,
+                          uint32_t flags)
+   {
+#if defined(BOTAN_HAS_BCRYPT)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_ARG_NON_NULL(out);
+      BOTAN_ASSERT_ARG_NON_NULL(out_len);
+      BOTAN_ASSERT_ARG_NON_NULL(pass);
+
+      if(flags != 0)
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+
+      if(wf < 2 || wf > 30)
+         throw FFI_Error("Bad bcrypt work factor " + std::to_string(wf));
+
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+      const std::string bcrypt = Botan::generate_bcrypt(pass, rng, wf);
+      return write_str_output(out, out_len, bcrypt);
+      });
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_bcrypt_is_valid(const char* pass, const char* hash)
+   {
+#if defined(BOTAN_HAS_BCRYPT)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      return Botan::check_bcrypt(pass, hash) ? 0 : 1;
+      });
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+}
diff --git a/src/lib/ffi/ffi_keywrap.cpp b/src/lib/ffi/ffi_keywrap.cpp
new file mode 100644
index 000000000..d881140d6
--- /dev/null
+++ b/src/lib/ffi/ffi_keywrap.cpp
@@ -0,0 +1,50 @@
+/*
+* (C) 2017 Ribose Inc
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+
+#if defined(BOTAN_HAS_RFC3394_KEYWRAP)
+   #include <botan/rfc3394.h>
+#endif
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+int botan_key_wrap3394(uint8_t key[], size_t key_len,
+                       uint8_t kek[], size_t kek_len,
+                       uint8_t wrapped_key[], size_t* wrapped_key_len)
+   {
+#if defined(BOTAN_HAS_RFC3394_KEYWRAP)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      const Botan::SymmetricKey kek_sym(kek, kek_len);
+      const Botan::secure_vector<uint8_t> key_pt(key, key + key_len);
+      const Botan::secure_vector<uint8_t> key_ct = Botan::rfc3394_keywrap(key_pt, kek_sym);
+      return write_vec_output(wrapped_key, wrapped_key_len, key_ct);
+      });
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_key_unwrap3394(uint8_t wrapped_key[], size_t wrapped_key_len,
+                         uint8_t kek[], size_t kek_len,
+                         uint8_t key[], size_t* key_len)
+   {
+#if defined(BOTAN_HAS_RFC3394_KEYWRAP)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      const Botan::SymmetricKey kek_sym(kek, kek_len);
+      const Botan::secure_vector<uint8_t> key_ct(wrapped_key, wrapped_key + wrapped_key_len);
+      const Botan::secure_vector<uint8_t> key_pt = Botan::rfc3394_keyunwrap(key_ct, kek_sym);
+      return write_vec_output(key, key_len, key_pt);
+      });
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+}
diff --git a/src/lib/ffi/ffi_mac.cpp b/src/lib/ffi/ffi_mac.cpp
new file mode 100644
index 000000000..b3237592f
--- /dev/null
+++ b/src/lib/ffi/ffi_mac.cpp
@@ -0,0 +1,64 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/mac.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_mac_struct, Botan::MessageAuthenticationCode, 0xA06E8FC1);
+
+int botan_mac_init(botan_mac_t* mac, const char* mac_name, uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(!mac || !mac_name || flags != 0)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      std::unique_ptr<Botan::MessageAuthenticationCode> m =
+         Botan::MessageAuthenticationCode::create(mac_name);
+
+      if(m == nullptr)
+         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+
+      *mac = new botan_mac_struct(m.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_mac_destroy(botan_mac_t mac)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(mac);
+   }
+
+int botan_mac_set_key(botan_mac_t mac, const uint8_t* key, size_t key_len)
+   {
+   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.set_key(key, key_len); });
+   }
+
+int botan_mac_output_length(botan_mac_t mac, size_t* out)
+   {
+   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { *out = m.output_length(); });
+   }
+
+int botan_mac_clear(botan_mac_t mac)
+   {
+   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.clear(); });
+   }
+
+int botan_mac_update(botan_mac_t mac, const uint8_t* buf, size_t len)
+   {
+   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.update(buf, len); });
+   }
+
+int botan_mac_final(botan_mac_t mac, uint8_t out[])
+   {
+   return BOTAN_FFI_DO(Botan::MessageAuthenticationCode, mac, m, { m.final(out); });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_mp.cpp b/src/lib/ffi/ffi_mp.cpp
new file mode 100644
index 000000000..00ad786ab
--- /dev/null
+++ b/src/lib/ffi/ffi_mp.cpp
@@ -0,0 +1,280 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+* (C) 2017 Ribose Inc
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/internal/ffi_rng.h>
+#include <botan/internal/ffi_mp.h>
+#include <botan/reducer.h>
+#include <botan/numthry.h>
+#include <botan/divide.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+int botan_mp_init(botan_mp_t* mp_out)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_ARG_NON_NULL(mp_out);
+
+      *mp_out = new botan_mp_struct(new Botan::BigInt);
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_mp_clear(botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.clear(); });
+   }
+
+int botan_mp_set_from_int(botan_mp_t mp, int initial_value)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
+      if(initial_value >= 0)
+         {
+         bn = Botan::BigInt(static_cast<uint64_t>(initial_value));
+         }
+      else
+         {
+         bn = Botan::BigInt(static_cast<uint64_t>(-initial_value));
+         bn.flip_sign();
+         }
+      });
+   }
+
+int botan_mp_set_from_str(botan_mp_t mp, const char* str)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn = Botan::BigInt(str); });
+   }
+
+int botan_mp_set_from_radix_str(botan_mp_t mp, const char* str, size_t radix)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
+      Botan::BigInt::Base base;
+      if(radix == 10)
+         base = Botan::BigInt::Decimal;
+      else if(radix == 16)
+         base = Botan::BigInt::Hexadecimal;
+      else
+         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+
+      const uint8_t* bytes = reinterpret_cast<const uint8_t*>(str);
+      const size_t len = strlen(str);
+
+      bn = Botan::BigInt::decode(bytes, len, base);
+      });
+   }
+
+int botan_mp_set_from_mp(botan_mp_t dest, const botan_mp_t source)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, dest, bn, { bn = safe_get(source); });
+   }
+
+int botan_mp_is_negative(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_negative() ? 1 : 0; });
+   }
+
+int botan_mp_is_positive(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_positive() ? 1 : 0; });
+   }
+
+int botan_mp_flip_sign(botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.flip_sign(); });
+   }
+
+int botan_mp_from_bin(botan_mp_t mp, const uint8_t bin[], size_t bin_len)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.binary_decode(bin, bin_len); });
+   }
+
+int botan_mp_to_hex(const botan_mp_t mp, char* out)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
+      std::vector<uint8_t> hex = Botan::BigInt::encode(bn, Botan::BigInt::Hexadecimal);
+      std::memcpy(out, hex.data(), hex.size());
+      out[hex.size()] = 0; // null terminate
+      });
+   }
+
+int botan_mp_to_str(const botan_mp_t mp, uint8_t digit_base, char* out, size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, {
+      Botan::BigInt::Base base;
+      if(digit_base == 0 || digit_base == 10)
+         base = Botan::BigInt::Decimal;
+      else if(digit_base == 16)
+         base = Botan::BigInt::Hexadecimal;
+      else
+         throw FFI_Error("botan_mp_to_str invalid digit base");
+
+      std::vector<uint8_t> hex = Botan::BigInt::encode(bn, base);
+      hex.push_back(0); // null terminator
+      return write_str_output(out, out_len, hex);
+      });
+   }
+
+int botan_mp_to_bin(const botan_mp_t mp, uint8_t vec[])
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { bn.binary_encode(vec); });
+   }
+
+int botan_mp_to_uint32(const botan_mp_t mp, uint32_t* val)
+   {
+   if(val == nullptr) {
+   return BOTAN_FFI_ERROR_NULL_POINTER;
+   }
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { *val = bn.to_u32bit(); });
+   }
+
+int botan_mp_destroy(botan_mp_t mp)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(mp);
+   }
+
+int botan_mp_add(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) + safe_get(y); });
+   }
+
+int botan_mp_sub(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) - safe_get(y); });
+   }
+
+int botan_mp_mul(botan_mp_t result, const botan_mp_t x, const botan_mp_t y)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, result, res, { res = safe_get(x) * safe_get(y); });
+   }
+
+int botan_mp_div(botan_mp_t quotient,
+                 botan_mp_t remainder,
+                 const botan_mp_t x, const botan_mp_t y)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, quotient, q, {
+      Botan::BigInt r;
+      Botan::divide(safe_get(x), safe_get(y), q, r);
+      safe_get(remainder) = r;
+      });
+   }
+
+int botan_mp_equal(const botan_mp_t x_w, const botan_mp_t y_w)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { return x == safe_get(y_w); });
+   }
+
+int botan_mp_is_zero(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_zero(); });
+   }
+
+int botan_mp_is_odd(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_odd(); });
+   }
+
+int botan_mp_is_even(const botan_mp_t mp)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, bn, { return bn.is_even(); });
+   }
+
+int botan_mp_cmp(int* result, const botan_mp_t x_w, const botan_mp_t y_w)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { *result = x.cmp(safe_get(y_w)); });
+   }
+
+int botan_mp_swap(botan_mp_t x_w, botan_mp_t y_w)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, x_w, x, { x.swap(safe_get(y_w)); });
+   }
+
+// Return (base^exponent) % modulus
+int botan_mp_powmod(botan_mp_t out, const botan_mp_t base, const botan_mp_t exponent, const botan_mp_t modulus)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, out, o,
+                       { o = Botan::power_mod(safe_get(base), safe_get(exponent), safe_get(modulus)); });
+   }
+
+int botan_mp_lshift(botan_mp_t out, const botan_mp_t in, size_t shift)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = safe_get(in) << shift; });
+   }
+
+int botan_mp_rshift(botan_mp_t out, const botan_mp_t in, size_t shift)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = safe_get(in) >> shift; });
+   }
+
+int botan_mp_mod_inverse(botan_mp_t out, const botan_mp_t in, const botan_mp_t modulus)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, out, o, { o = Botan::inverse_mod(safe_get(in), safe_get(modulus)); });
+   }
+
+int botan_mp_mod_mul(botan_mp_t out, const botan_mp_t x, const botan_mp_t y, const botan_mp_t modulus)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, out, o, {
+      Botan::Modular_Reducer reducer(safe_get(modulus));
+      o = reducer.multiply(safe_get(x), safe_get(y));
+      });
+   }
+
+int botan_mp_rand_bits(botan_mp_t rand_out, botan_rng_t rng, size_t bits)
+   {
+   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, {
+      safe_get(rand_out).randomize(r, bits); });
+   }
+
+int botan_mp_rand_range(botan_mp_t rand_out,
+                        botan_rng_t rng,
+                        const botan_mp_t lower,
+                        const botan_mp_t upper)
+   {
+   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, {
+      safe_get(rand_out) = Botan::BigInt::random_integer(r, safe_get(lower), safe_get(upper)); });
+   }
+
+int botan_mp_gcd(botan_mp_t out, const botan_mp_t x, const botan_mp_t y)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, out, o, {
+      o = Botan::gcd(safe_get(x), safe_get(y)); });
+   }
+
+int botan_mp_is_prime(const botan_mp_t mp, botan_rng_t rng, size_t test_prob)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n,
+                       { return (Botan::is_prime(n, safe_get(rng), test_prob)) ? 1 : 0; });
+   }
+
+int botan_mp_get_bit(const botan_mp_t mp, size_t bit)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { return (n.get_bit(bit)); });
+   }
+
+int botan_mp_set_bit(botan_mp_t mp, size_t bit)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { n.set_bit(bit); });
+   }
+
+int botan_mp_clear_bit(botan_mp_t mp, size_t bit)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { n.clear_bit(bit); });
+   }
+
+int botan_mp_num_bits(const botan_mp_t mp, size_t* bits)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { *bits = n.bits(); });
+   }
+
+int botan_mp_num_bytes(const botan_mp_t mp, size_t* bytes)
+   {
+   return BOTAN_FFI_DO(Botan::BigInt, mp, n, { *bytes = n.bytes(); });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_mp.h b/src/lib/ffi/ffi_mp.h
new file mode 100644
index 000000000..fb2e2dee5
--- /dev/null
+++ b/src/lib/ffi/ffi_mp.h
@@ -0,0 +1,21 @@
+/*
+* (C) 2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_FFI_MP_H__
+#define BOTAN_FFI_MP_H__
+
+#include <botan/bigint.h>
+#include <botan/internal/ffi_util.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_mp_struct, Botan::BigInt, 0xC828B9D2);
+
+}
+
+#endif
diff --git a/src/lib/ffi/ffi_pk_op.cpp b/src/lib/ffi/ffi_pk_op.cpp
new file mode 100644
index 000000000..d0ac8e3c7
--- /dev/null
+++ b/src/lib/ffi/ffi_pk_op.cpp
@@ -0,0 +1,216 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/internal/ffi_pkey.h>
+#include <botan/internal/ffi_rng.h>
+#include <botan/pubkey.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_encrypt_struct, Botan::PK_Encryptor, 0x891F3FC3);
+BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_decrypt_struct, Botan::PK_Decryptor, 0x912F3C37);
+BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_sign_struct, Botan::PK_Signer, 0x1AF0C39F);
+BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_verify_struct, Botan::PK_Verifier, 0x2B91F936);
+BOTAN_FFI_DECLARE_STRUCT(botan_pk_op_ka_struct, Botan::PK_Key_Agreement, 0x2939CAB1);
+
+int botan_pk_op_encrypt_create(botan_pk_op_encrypt_t* op,
+                               botan_pubkey_t key_obj,
+                               const char* padding,
+                               uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_NONNULL(op);
+
+      *op = nullptr;
+
+      if(flags != 0)
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+
+      std::unique_ptr<Botan::PK_Encryptor> pk(new Botan::PK_Encryptor_EME(safe_get(key_obj), Botan::system_rng(), padding));
+      *op = new botan_pk_op_encrypt_struct(pk.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pk_op_encrypt_destroy(botan_pk_op_encrypt_t op)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(op);
+   }
+
+int botan_pk_op_encrypt(botan_pk_op_encrypt_t op,
+                        botan_rng_t rng_obj,
+                        uint8_t out[], size_t* out_len,
+                        const uint8_t plaintext[], size_t plaintext_len)
+   {
+   return BOTAN_FFI_DO(Botan::PK_Encryptor, op, o, {
+      return write_vec_output(out, out_len, o.encrypt(plaintext, plaintext_len, safe_get(rng_obj)));
+      });
+   }
+
+/*
+* Public Key Decryption
+*/
+int botan_pk_op_decrypt_create(botan_pk_op_decrypt_t* op,
+                               botan_privkey_t key_obj,
+                               const char* padding,
+                               uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_NONNULL(op);
+
+      *op = nullptr;
+
+      if(flags != 0)
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+
+      std::unique_ptr<Botan::PK_Decryptor> pk(new Botan::PK_Decryptor_EME(safe_get(key_obj), Botan::system_rng(), padding));
+      *op = new botan_pk_op_decrypt_struct(pk.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pk_op_decrypt_destroy(botan_pk_op_decrypt_t op)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(op);
+   }
+
+int botan_pk_op_decrypt(botan_pk_op_decrypt_t op,
+                        uint8_t out[], size_t* out_len,
+                        const uint8_t ciphertext[], size_t ciphertext_len)
+   {
+   return BOTAN_FFI_DO(Botan::PK_Decryptor, op, o, {
+      return write_vec_output(out, out_len, o.decrypt(ciphertext, ciphertext_len));
+      });
+   }
+
+/*
+* Signature Generation
+*/
+int botan_pk_op_sign_create(botan_pk_op_sign_t* op,
+                            botan_privkey_t key_obj,
+                            const char* hash,
+                            uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_NONNULL(op);
+
+      *op = nullptr;
+
+      if(flags != 0)
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+
+      std::unique_ptr<Botan::PK_Signer> pk(new Botan::PK_Signer(safe_get(key_obj),Botan::system_rng(),  hash));
+      *op = new botan_pk_op_sign_struct(pk.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pk_op_sign_destroy(botan_pk_op_sign_t op)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(op);
+   }
+
+int botan_pk_op_sign_update(botan_pk_op_sign_t op, const uint8_t in[], size_t in_len)
+   {
+   return BOTAN_FFI_DO(Botan::PK_Signer, op, o, { o.update(in, in_len); });
+   }
+
+int botan_pk_op_sign_finish(botan_pk_op_sign_t op, botan_rng_t rng_obj, uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::PK_Signer, op, o, {
+      return write_vec_output(out, out_len, o.signature(safe_get(rng_obj)));
+      });
+   }
+
+int botan_pk_op_verify_create(botan_pk_op_verify_t* op,
+                              botan_pubkey_t key_obj,
+                              const char* hash,
+                              uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_NONNULL(op);
+
+      if(flags != 0)
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+
+      std::unique_ptr<Botan::PK_Verifier> pk(new Botan::PK_Verifier(safe_get(key_obj), hash));
+      *op = new botan_pk_op_verify_struct(pk.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pk_op_verify_destroy(botan_pk_op_verify_t op)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(op);
+   }
+
+int botan_pk_op_verify_update(botan_pk_op_verify_t op, const uint8_t in[], size_t in_len)
+   {
+   return BOTAN_FFI_DO(Botan::PK_Verifier, op, o, { o.update(in, in_len); });
+   }
+
+int botan_pk_op_verify_finish(botan_pk_op_verify_t op, const uint8_t sig[], size_t sig_len)
+   {
+   return BOTAN_FFI_DO(Botan::PK_Verifier, op, o, {
+      const bool legit = o.check_signature(sig, sig_len);
+
+      if(legit)
+         return BOTAN_FFI_SUCCESS;
+      else
+         return BOTAN_FFI_ERROR_INVALID_INPUT;
+      });
+   }
+
+int botan_pk_op_key_agreement_create(botan_pk_op_ka_t* op,
+                                     botan_privkey_t key_obj,
+                                     const char* kdf,
+                                     uint32_t flags)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_NONNULL(op);
+
+      *op = nullptr;
+
+      if(flags != 0)
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+
+      std::unique_ptr<Botan::PK_Key_Agreement> pk(new Botan::PK_Key_Agreement(safe_get(key_obj), Botan::system_rng(), kdf));
+      *op = new botan_pk_op_ka_struct(pk.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pk_op_key_agreement_destroy(botan_pk_op_ka_t op)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(op);
+   }
+
+int botan_pk_op_key_agreement_export_public(botan_privkey_t key,
+                                            uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
+      if(auto kak = dynamic_cast<const Botan::PK_Key_Agreement_Key*>(&k))
+         return write_vec_output(out, out_len, kak->public_value());
+      return BOTAN_FFI_ERROR_BAD_FLAG;
+      });
+   }
+
+int botan_pk_op_key_agreement(botan_pk_op_ka_t op,
+                              uint8_t out[], size_t* out_len,
+                              const uint8_t other_key[], size_t other_key_len,
+                              const uint8_t salt[], size_t salt_len)
+   {
+   return BOTAN_FFI_DO(Botan::PK_Key_Agreement, op, o, {
+      auto k = o.derive_key(*out_len, other_key, other_key_len, salt, salt_len).bits_of();
+      return write_vec_output(out, out_len, k);
+      });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_pkey.cpp b/src/lib/ffi/ffi_pkey.cpp
new file mode 100644
index 000000000..1577118b1
--- /dev/null
+++ b/src/lib/ffi/ffi_pkey.cpp
@@ -0,0 +1,263 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/internal/ffi_pkey.h>
+#include <botan/internal/ffi_rng.h>
+#include <botan/hash.h>
+#include <botan/pkcs8.h>
+#include <botan/x509_key.h>
+#include <botan/pk_algs.h>
+
+#if defined(BOTAN_HAS_HASH_ID)
+  #include <botan/hash_id.h>
+#endif
+
+extern "C" {
+
+int botan_privkey_create(botan_privkey_t* key_obj,
+                         const char* algo_name,
+                         const char* algo_params,
+                         botan_rng_t rng_obj)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(key_obj == nullptr)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      *key_obj = nullptr;
+      if(rng_obj == nullptr)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+      std::unique_ptr<Botan::Private_Key> key(
+         Botan::create_private_key(algo_name ? algo_name : "RSA",
+                                   rng,
+                                   algo_params ? algo_params : ""));
+
+      if(key)
+         {
+         *key_obj = new botan_privkey_struct(key.release());
+         return BOTAN_FFI_SUCCESS;
+         }
+      else
+         {
+         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+         }
+      });
+   }
+
+int botan_privkey_load(botan_privkey_t* key, botan_rng_t rng_obj,
+                       const uint8_t bits[], size_t len,
+                       const char* password)
+   {
+   *key = nullptr;
+
+   if(password == nullptr)
+      password = "";
+
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::DataSource_Memory src(bits, len);
+
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+
+      std::unique_ptr<Botan::PKCS8_PrivateKey> pkcs8(
+         Botan::PKCS8::load_key(src, rng, static_cast<std::string>(password)));
+
+      if(pkcs8)
+         {
+         *key = new botan_privkey_struct(pkcs8.release());
+         return BOTAN_FFI_SUCCESS;
+         }
+      return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
+      });
+   }
+
+int botan_privkey_destroy(botan_privkey_t key)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(key);
+   }
+
+int botan_pubkey_load(botan_pubkey_t* key,
+                      const uint8_t bits[], size_t bits_len)
+   {
+   *key = nullptr;
+
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::DataSource_Memory src(bits, bits_len);
+      std::unique_ptr<Botan::Public_Key> pubkey(Botan::X509::load_key(src));
+
+      if(pubkey == nullptr)
+         return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
+
+      *key = new botan_pubkey_struct(pubkey.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pubkey_destroy(botan_pubkey_t key)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(key);
+   }
+
+int botan_privkey_export_pubkey(botan_pubkey_t* pubout, botan_privkey_t key_obj)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::Public_Key>
+         pubkey(Botan::X509::load_key(Botan::X509::BER_encode(safe_get(key_obj))));
+
+      *pubout = new botan_pubkey_struct(pubkey.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_pubkey_algo_name(botan_pubkey_t key, char out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::Public_Key, key, k, { return write_str_output(out, out_len, k.algo_name()); });
+   }
+
+int botan_pubkey_check_key(botan_pubkey_t key, botan_rng_t rng, uint32_t flags)
+   {
+   const bool strong = (flags & BOTAN_CHECK_KEY_EXPENSIVE_TESTS);
+
+   return BOTAN_FFI_DO(Botan::Public_Key, key, k,
+                       { return (k.check_key(safe_get(rng), strong) == true) ? 0 : -1; });
+   }
+
+int botan_privkey_check_key(botan_privkey_t key, botan_rng_t rng, uint32_t flags)
+   {
+   const bool strong = (flags & BOTAN_CHECK_KEY_EXPENSIVE_TESTS);
+   return BOTAN_FFI_DO(Botan::Private_Key, key, k,
+                       { return (k.check_key(safe_get(rng), strong) == true) ? 0 : -1; });
+   }
+
+int botan_pubkey_export(botan_pubkey_t key, uint8_t out[], size_t* out_len, uint32_t flags)
+   {
+   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
+      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
+         return write_vec_output(out, out_len, Botan::X509::BER_encode(k));
+      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
+         return write_str_output(out, out_len, Botan::X509::PEM_encode(k));
+      else
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+      });
+   }
+
+int botan_privkey_export(botan_privkey_t key, uint8_t out[], size_t* out_len, uint32_t flags)
+   {
+   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
+      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
+         return write_vec_output(out, out_len, Botan::PKCS8::BER_encode(k));
+      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
+         return write_str_output(out, out_len, Botan::PKCS8::PEM_encode(k));
+      else
+         return BOTAN_FFI_ERROR_BAD_FLAG;
+      });
+   }
+
+int botan_privkey_export_encrypted(botan_privkey_t key,
+                                   uint8_t out[], size_t* out_len,
+                                   botan_rng_t rng_obj,
+                                   const char* pass,
+                                   const char* /*ignored - pbe*/,
+                                   uint32_t flags)
+   {
+   return botan_privkey_export_encrypted_pbkdf_iter(key, out, out_len, rng_obj, pass, 100000, nullptr, nullptr, flags);
+   }
+
+int botan_privkey_export_encrypted_pbkdf_msec(botan_privkey_t key,
+                                              uint8_t out[], size_t* out_len,
+                                              botan_rng_t rng_obj,
+                                              const char* pass,
+                                              uint32_t pbkdf_msec,
+                                              size_t* pbkdf_iters_out,
+                                              const char* maybe_cipher,
+                                              const char* maybe_pbkdf_hash,
+                                              uint32_t flags)
+   {
+   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
+      const std::chrono::milliseconds pbkdf_time(pbkdf_msec);
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+
+      const std::string cipher = (maybe_cipher ? maybe_cipher : "");
+      const std::string pbkdf_hash = (maybe_pbkdf_hash ? maybe_pbkdf_hash : "");
+
+      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
+         {
+         return write_vec_output(out, out_len,
+                                 Botan::PKCS8::BER_encode_encrypted_pbkdf_msec(k, rng, pass, pbkdf_time, pbkdf_iters_out, cipher, pbkdf_hash));
+         }
+      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
+         {
+         return write_str_output(out, out_len,
+                                 Botan::PKCS8::PEM_encode_encrypted_pbkdf_msec(k, rng, pass, pbkdf_time, pbkdf_iters_out, cipher, pbkdf_hash));
+         }
+      else
+         {
+         return -2;
+         }
+      });
+   }
+
+int botan_privkey_export_encrypted_pbkdf_iter(botan_privkey_t key,
+                                              uint8_t out[], size_t* out_len,
+                                              botan_rng_t rng_obj,
+                                              const char* pass,
+                                              size_t pbkdf_iter,
+                                              const char* maybe_cipher,
+                                              const char* maybe_pbkdf_hash,
+                                              uint32_t flags)
+   {
+   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+
+      const std::string cipher = (maybe_cipher ? maybe_cipher : "");
+      const std::string pbkdf_hash = (maybe_pbkdf_hash ? maybe_pbkdf_hash : "");
+
+      if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_DER)
+         {
+         return write_vec_output(out, out_len,
+                                 Botan::PKCS8::BER_encode_encrypted_pbkdf_iter(k, rng, pass, pbkdf_iter, cipher, pbkdf_hash));
+         }
+      else if(flags == BOTAN_PRIVKEY_EXPORT_FLAG_PEM)
+         {
+         return write_str_output(out, out_len,
+                                 Botan::PKCS8::PEM_encode_encrypted_pbkdf_iter(k, rng, pass, pbkdf_iter, cipher, pbkdf_hash));
+         }
+      else
+         {
+         return -2;
+         }
+      });
+   }
+
+int botan_pubkey_estimated_strength(botan_pubkey_t key, size_t* estimate)
+   {
+   return BOTAN_FFI_DO(Botan::Public_Key, key, k, { *estimate = k.estimated_strength(); });
+   }
+
+int botan_pubkey_fingerprint(botan_pubkey_t key, const char* hash_fn,
+                             uint8_t out[], size_t* out_len)
+   {
+   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
+      std::unique_ptr<Botan::HashFunction> h(Botan::HashFunction::create(hash_fn));
+      return write_vec_output(out, out_len, h->process(k.public_key_bits()));
+      });
+   }
+
+int botan_pkcs_hash_id(const char* hash_name, uint8_t pkcs_id[], size_t* pkcs_id_len)
+   {
+#if defined(BOTAN_HAS_HASH_ID)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      const std::vector<uint8_t> hash_id = Botan::pkcs_hash_id(hash_name);
+      return write_output(pkcs_id, pkcs_id_len, hash_id.data(), hash_id.size());
+      });
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+}
diff --git a/src/lib/ffi/ffi_pkey.h b/src/lib/ffi/ffi_pkey.h
new file mode 100644
index 000000000..536e5fc29
--- /dev/null
+++ b/src/lib/ffi/ffi_pkey.h
@@ -0,0 +1,22 @@
+/*
+* (C) 2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_FFI_PKEY_H__
+#define BOTAN_FFI_PKEY_H__
+
+#include <botan/pk_keys.h>
+#include <botan/internal/ffi_util.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_pubkey_struct, Botan::Public_Key, 0x2C286519);
+BOTAN_FFI_DECLARE_STRUCT(botan_privkey_struct, Botan::Private_Key, 0x7F96385E);
+
+}
+
+#endif
diff --git a/src/lib/ffi/ffi_pkey_algs.cpp b/src/lib/ffi/ffi_pkey_algs.cpp
new file mode 100644
index 000000000..8cb9b785e
--- /dev/null
+++ b/src/lib/ffi/ffi_pkey_algs.cpp
@@ -0,0 +1,757 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+* (C) 2017 Ribose Inc
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/internal/ffi_pkey.h>
+#include <botan/internal/ffi_rng.h>
+#include <botan/internal/ffi_mp.h>
+
+#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
+  #include <botan/ecc_key.h>
+#endif
+
+#if defined(BOTAN_HAS_DL_PUBLIC_KEY_FAMILY)
+  #include <botan/dl_algo.h>
+#endif
+
+#if defined(BOTAN_HAS_RSA)
+  #include <botan/rsa.h>
+#endif
+
+#if defined(BOTAN_HAS_ELGAMAL)
+  #include <botan/elgamal.h>
+#endif
+
+#if defined(BOTAN_HAS_DSA)
+  #include <botan/dsa.h>
+#endif
+
+#if defined(BOTAN_HAS_ECDSA)
+  #include <botan/ecdsa.h>
+#endif
+
+#if defined(BOTAN_HAS_SM2)
+  #include <botan/sm2.h>
+#endif
+
+#if defined(BOTAN_HAS_ECDH)
+  #include <botan/ecdh.h>
+#endif
+
+#if defined(BOTAN_HAS_CURVE_25519)
+  #include <botan/curve25519.h>
+#endif
+
+#if defined(BOTAN_HAS_ED25519)
+  #include <botan/ed25519.h>
+#endif
+
+#if defined(BOTAN_HAS_MCELIECE)
+  #include <botan/mceliece.h>
+#endif
+
+#if defined(BOTAN_HAS_MCEIES)
+  #include <botan/mceies.h>
+#endif
+
+namespace {
+
+#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
+
+// These are always called within an existing try/catch block
+
+template<class ECPrivateKey_t>
+int privkey_load_ec(std::unique_ptr<ECPrivateKey_t>& key,
+                    const Botan::BigInt& scalar,
+                    const char* curve_name)
+   {
+   if(curve_name == nullptr)
+      return BOTAN_FFI_ERROR_NULL_POINTER;
+
+   Botan::Null_RNG null_rng;
+   Botan::EC_Group grp(curve_name);
+   key.reset(new ECPrivateKey_t(null_rng, grp, scalar));
+   return BOTAN_FFI_SUCCESS;
+   }
+
+template<class ECPublicKey_t>
+int pubkey_load_ec(std::unique_ptr<ECPublicKey_t>& key,
+                   const Botan::BigInt& public_x,
+                   const Botan::BigInt& public_y,
+                   const char* curve_name)
+   {
+   if(curve_name == nullptr)
+      return BOTAN_FFI_ERROR_NULL_POINTER;
+
+   Botan::Null_RNG null_rng;
+   Botan::EC_Group grp(curve_name);
+   Botan::PointGFp uncompressed_point(grp.get_curve(), public_x, public_y);
+   key.reset(new ECPublicKey_t(grp, uncompressed_point));
+   return BOTAN_FFI_SUCCESS;
+   }
+
+#endif
+
+Botan::BigInt pubkey_get_field(const Botan::Public_Key& key,
+                               const std::string& field)
+   {
+   // Maybe this should be `return key.get_integer_field(field_name)`?
+
+#if defined(BOTAN_HAS_RSA)
+   if(const Botan::RSA_PublicKey* rsa = dynamic_cast<const Botan::RSA_PublicKey*>(&key))
+      {
+      if(field == "n")
+         return rsa->get_n();
+      else if(field == "e")
+         return rsa->get_e();
+      else
+         throw Botan::Exception("Field not supported");
+      }
+#endif
+
+#if defined(BOTAN_HAS_DL_PUBLIC_KEY_FAMILY)
+   // Handles DSA, ElGamal, etc
+   if(const Botan::DL_Scheme_PublicKey* dl = dynamic_cast<const Botan::DL_Scheme_PublicKey*>(&key))
+      {
+      if(field == "p")
+         return dl->group_p();
+      else if(field == "q")
+         return dl->group_q();
+      else if(field == "g")
+         return dl->group_g();
+      else if(field == "y")
+         return dl->get_y();
+      else
+         throw Botan::Exception("Field not supported");
+      }
+#endif
+
+#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
+   if(const Botan::EC_PublicKey* ecc = dynamic_cast<const Botan::EC_PublicKey*>(&key))
+      {
+      if(field == "public_x")
+         return ecc->public_point().get_affine_x();
+      else if(field == "public_y")
+         return ecc->public_point().get_affine_y();
+      else if(field == "base_x")
+         return ecc->domain().get_base_point().get_affine_x();
+      else if(field == "base_y")
+         return ecc->domain().get_base_point().get_affine_y();
+      else if(field == "p")
+         return ecc->domain().get_curve().get_p();
+      else if(field == "a")
+         return ecc->domain().get_curve().get_a();
+      else if(field == "b")
+         return ecc->domain().get_curve().get_b();
+      else if(field == "cofactor")
+         return ecc->domain().get_cofactor();
+      else if(field == "order")
+         return ecc->domain().get_order();
+      else
+         throw Botan::Exception("Field not supported");
+      }
+#endif
+
+   // Some other algorithm type not supported by this function
+   throw Botan::Exception("Unsupported algorithm type for botan_pubkey_get_field");
+   }
+
+Botan::BigInt privkey_get_field(const Botan::Private_Key& key,
+                                const std::string& field)
+   {
+   //return key.get_integer_field(field);
+
+#if defined(BOTAN_HAS_RSA)
+
+   if(const Botan::RSA_PrivateKey* rsa = dynamic_cast<const Botan::RSA_PrivateKey*>(&key))
+      {
+      if(field == "p")
+         return rsa->get_p();
+      else if(field == "q")
+         return rsa->get_q();
+      else if(field == "d")
+         return rsa->get_d();
+      else if(field == "c")
+         return rsa->get_c();
+      else if(field == "d1")
+         return rsa->get_d1();
+      else if(field == "d2")
+         return rsa->get_d2();
+      else
+         return pubkey_get_field(key, field);
+      }
+#endif
+
+#if defined(BOTAN_HAS_DL_PUBLIC_KEY_FAMILY)
+   // Handles DSA, ElGamal, etc
+   if(const Botan::DL_Scheme_PrivateKey* dl = dynamic_cast<const Botan::DL_Scheme_PrivateKey*>(&key))
+      {
+      if(field == "x")
+         return dl->get_x();
+      else
+         return pubkey_get_field(key, field);
+      }
+#endif
+
+#if defined(BOTAN_HAS_ECC_PUBLIC_KEY_CRYPTO)
+   if(const Botan::EC_PrivateKey* ecc = dynamic_cast<const Botan::EC_PrivateKey*>(&key))
+      {
+      if(field == "x")
+         return ecc->private_value();
+      else
+         return pubkey_get_field(key, field);
+      }
+#endif
+
+   // Some other algorithm type not supported by this function
+   throw Botan::Exception("Unsupported algorithm type for botan_privkey_get_field");
+   }
+
+}
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+int botan_pubkey_get_field(botan_mp_t output,
+                           botan_pubkey_t key,
+                           const char* field_name_cstr)
+   {
+   if(field_name_cstr == nullptr)
+      return BOTAN_FFI_ERROR_NULL_POINTER;
+
+   const std::string field_name(field_name_cstr);
+
+   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
+      safe_get(output) = pubkey_get_field(k, field_name);
+      });
+   }
+
+int botan_privkey_get_field(botan_mp_t output,
+                                      botan_privkey_t key,
+                                      const char* field_name_cstr)
+   {
+   if(field_name_cstr == nullptr)
+      return BOTAN_FFI_ERROR_NULL_POINTER;
+
+   const std::string field_name(field_name_cstr);
+
+   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
+      safe_get(output) = privkey_get_field(k, field_name);
+      });
+   }
+
+/* RSA specific operations */
+
+int botan_privkey_create_rsa(botan_privkey_t* key_obj, botan_rng_t rng_obj, size_t n_bits)
+   {
+#if defined(BOTAN_HAS_RSA)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(key_obj == nullptr || rng_obj == nullptr)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+      if(n_bits < 1024 || n_bits > 16*1024)
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
+
+      *key_obj = nullptr;
+
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+      std::unique_ptr<Botan::Private_Key> key(new Botan::RSA_PrivateKey(rng, n_bits));
+      *key_obj = new botan_privkey_struct(key.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_load_rsa(botan_privkey_t* key,
+                           botan_mp_t rsa_p, botan_mp_t rsa_q, botan_mp_t rsa_e)
+   {
+#if defined(BOTAN_HAS_RSA)
+   *key = nullptr;
+
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      *key = new botan_privkey_struct(new Botan::RSA_PrivateKey(safe_get(rsa_p),
+                                                                safe_get(rsa_q),
+                                                                safe_get(rsa_e)));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, rsa_p, rsa_q, rsa_e);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_pubkey_load_rsa(botan_pubkey_t* key,
+                          botan_mp_t n, botan_mp_t e)
+   {
+#if defined(BOTAN_HAS_RSA)
+   *key = nullptr;
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      *key = new botan_pubkey_struct(new Botan::RSA_PublicKey(safe_get(n), safe_get(e)));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, n, e);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_rsa_get_p(botan_mp_t p, botan_privkey_t key)
+   {
+   return botan_privkey_get_field(p, key, "p");
+   }
+
+int botan_privkey_rsa_get_q(botan_mp_t q, botan_privkey_t key)
+   {
+   return botan_privkey_get_field(q, key, "q");
+   }
+
+int botan_privkey_rsa_get_n(botan_mp_t n, botan_privkey_t key)
+   {
+   return botan_privkey_get_field(n, key, "n");
+   }
+
+int botan_privkey_rsa_get_e(botan_mp_t e, botan_privkey_t key)
+   {
+   return botan_privkey_get_field(e, key, "e");
+   }
+
+int botan_privkey_rsa_get_d(botan_mp_t d, botan_privkey_t key)
+   {
+   return botan_privkey_get_field(d, key, "d");
+   }
+
+int botan_pubkey_rsa_get_e(botan_mp_t e, botan_pubkey_t key)
+   {
+   return botan_pubkey_get_field(e, key, "e");
+   }
+
+int botan_pubkey_rsa_get_n(botan_mp_t n, botan_pubkey_t key)
+   {
+   return botan_pubkey_get_field(n, key, "n");
+   }
+
+/* DSA specific operations */
+
+int botan_privkey_load_dsa(botan_privkey_t* key,
+                           botan_mp_t p, botan_mp_t q, botan_mp_t g, botan_mp_t x)
+   {
+#if defined(BOTAN_HAS_DSA)
+   *key = nullptr;
+
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::Null_RNG null_rng;
+      Botan::DL_Group group(safe_get(p), safe_get(q), safe_get(g));
+      *key = new botan_privkey_struct(new Botan::DSA_PrivateKey(null_rng, group, safe_get(x)));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, p, q, g, x);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_pubkey_load_dsa(botan_pubkey_t* key,
+                          botan_mp_t p, botan_mp_t q, botan_mp_t g, botan_mp_t y)
+   {
+#if defined(BOTAN_HAS_DSA)
+   *key = nullptr;
+
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::DL_Group group(safe_get(p), safe_get(q), safe_get(g));
+      *key = new botan_pubkey_struct(new Botan::DSA_PublicKey(group, safe_get(y)));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, p, q, g, y);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_dsa_get_x(botan_mp_t x, botan_privkey_t key)
+   {
+   return botan_privkey_get_field(x, key, "x");
+   }
+
+int botan_pubkey_dsa_get_p(botan_mp_t p, botan_pubkey_t key)
+   {
+   return botan_pubkey_get_field(p, key, "p");
+   }
+
+int botan_pubkey_dsa_get_q(botan_mp_t q, botan_pubkey_t key)
+   {
+   return botan_pubkey_get_field(q, key, "q");
+   }
+
+int botan_pubkey_dsa_get_g(botan_mp_t g, botan_pubkey_t key)
+   {
+   return botan_pubkey_get_field(g, key, "g");
+   }
+
+int botan_pubkey_dsa_get_y(botan_mp_t y, botan_pubkey_t key)
+   {
+   return botan_pubkey_get_field(y, key, "y");
+   }
+
+int botan_privkey_create_ecdsa(botan_privkey_t* key_obj, botan_rng_t rng_obj, const char* param_str)
+   {
+#if defined(BOTAN_HAS_ECDSA)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(key_obj == nullptr || rng_obj == nullptr || param_str == nullptr || *param_str == 0)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      *key_obj = nullptr;
+
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+      Botan::EC_Group grp(param_str);
+      std::unique_ptr<Botan::Private_Key> key(new Botan::ECDSA_PrivateKey(rng, grp));
+      *key_obj = new botan_privkey_struct(key.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+     return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+/* ECDSA specific operations */
+
+int botan_pubkey_load_ecdsa(botan_pubkey_t* key,
+                            const botan_mp_t public_x,
+                            const botan_mp_t public_y,
+                            const char* curve_name)
+   {
+#if defined(BOTAN_HAS_ECDSA)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::ECDSA_PublicKey> p_key;
+
+      int rc = pubkey_load_ec(p_key, safe_get(public_x), safe_get(public_y), curve_name);
+      if(rc == BOTAN_FFI_SUCCESS)
+         *key = new botan_pubkey_struct(p_key.release());
+
+      return rc;
+      });
+#else
+   BOTAN_UNUSED(key, public_x, public_y, curve_name);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_load_ecdsa(botan_privkey_t* key,
+                             const botan_mp_t scalar,
+                             const char* curve_name)
+   {
+#if defined(BOTAN_HAS_ECDSA)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::ECDSA_PrivateKey> p_key;
+      int rc = privkey_load_ec(p_key, safe_get(scalar), curve_name);
+      if(rc == BOTAN_FFI_SUCCESS)
+         *key = new botan_privkey_struct(p_key.release());
+      return rc;
+      });
+#else
+   BOTAN_UNUSED(key, scalar, curve_name);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+/* ElGamal specific operations */
+
+int botan_pubkey_load_elgamal(botan_pubkey_t* key,
+                              botan_mp_t p, botan_mp_t g, botan_mp_t y)
+   {
+#if defined(BOTAN_HAS_ELGAMAL)
+   *key = nullptr;
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::DL_Group group(safe_get(p), safe_get(g));
+      *key = new botan_pubkey_struct(new Botan::ElGamal_PublicKey(group, safe_get(y)));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, p, g, y);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_load_elgamal(botan_privkey_t* key,
+                               botan_mp_t p, botan_mp_t g, botan_mp_t x)
+   {
+#if defined(BOTAN_HAS_ELGAMAL)
+   *key = nullptr;
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::Null_RNG null_rng;
+      Botan::DL_Group group(safe_get(p), safe_get(g));
+      *key = new botan_privkey_struct(new Botan::ElGamal_PrivateKey(null_rng, group, safe_get(x)));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, p, g, x);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+/* ECDH + x25519 specific operations */
+
+int botan_privkey_create_ecdh(botan_privkey_t* key_obj, botan_rng_t rng_obj, const char* param_str)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(key_obj == nullptr || rng_obj == nullptr || param_str == nullptr || *param_str == 0)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      *key_obj = nullptr;
+
+      const std::string params(param_str);
+
+#if defined(BOTAN_HAS_CURVE_25519)
+      if(params == "curve25519")
+         {
+         std::unique_ptr<Botan::Private_Key> key(new Botan::Curve25519_PrivateKey(safe_get(rng_obj)));
+         *key_obj = new botan_privkey_struct(key.release());
+         return BOTAN_FFI_SUCCESS;
+         }
+#endif
+
+#if defined(BOTAN_HAS_ECDH)
+      Botan::EC_Group grp(params);
+      std::unique_ptr<Botan::Private_Key> key(new Botan::ECDH_PrivateKey(safe_get(rng_obj), grp));
+      *key_obj = new botan_privkey_struct(key.release());
+      return BOTAN_FFI_SUCCESS;
+#endif
+
+      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+      });
+   }
+
+int botan_pubkey_load_ecdh(botan_pubkey_t* key,
+                           const botan_mp_t public_x,
+                           const botan_mp_t public_y,
+                           const char* curve_name)
+   {
+#if defined(BOTAN_HAS_ECDH)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::ECDH_PublicKey> p_key;
+      int rc = pubkey_load_ec(p_key, safe_get(public_x), safe_get(public_y), curve_name);
+
+      if(rc == BOTAN_FFI_SUCCESS)
+         *key = new botan_pubkey_struct(p_key.release());
+      return rc;
+      });
+#else
+   BOTAN_UNUSED(key, public_x, public_y, curve_name);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_load_ecdh(botan_privkey_t* key,
+                            const botan_mp_t scalar,
+                            const char* curve_name)
+   {
+#if defined(BOTAN_HAS_ECDH)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::ECDH_PrivateKey> p_key;
+      int rc = privkey_load_ec(p_key, safe_get(scalar), curve_name);
+      if(rc == BOTAN_FFI_SUCCESS)
+         *key = new botan_privkey_struct(p_key.release());
+      return rc;
+      });
+#else
+   BOTAN_UNUSED(key, scalar, curve_name);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+/* SM2 specific operations */
+
+int botan_pubkey_load_sm2(botan_pubkey_t* key,
+                          const botan_mp_t public_x,
+                          const botan_mp_t public_y,
+                          const char* curve_name)
+   {
+#if defined(BOTAN_HAS_SM2)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::SM2_Signature_PublicKey> p_key;
+      if(!pubkey_load_ec(p_key, safe_get(public_x), safe_get(public_y), curve_name))
+         {
+         *key = new botan_pubkey_struct(p_key.release());
+         return BOTAN_FFI_SUCCESS;
+         }
+      return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
+      });
+#else
+   BOTAN_UNUSED(key, public_x, public_y, curve_name);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_load_sm2(botan_privkey_t* key,
+                           const botan_mp_t scalar,
+                           const char* curve_name)
+   {
+#if defined(BOTAN_HAS_SM2)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      std::unique_ptr<Botan::SM2_Signature_PrivateKey> p_key;
+      int rc = privkey_load_ec(p_key, safe_get(scalar), curve_name);
+
+      if(rc == BOTAN_FFI_SUCCESS)
+         *key = new botan_privkey_struct(p_key.release());
+      return rc;
+      });
+#else
+   BOTAN_UNUSED(key, scalar, curve_name);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+/* Ed25519 specific operations */
+
+int botan_privkey_load_ed25519(botan_privkey_t* key,
+                               const uint8_t privkey[32])
+   {
+#if defined(BOTAN_HAS_ED25519)
+   *key = nullptr;
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      const Botan::secure_vector<uint8_t> privkey_vec(privkey, privkey + 32);
+      *key = new botan_privkey_struct(new Botan::Ed25519_PrivateKey(privkey_vec));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, privkey);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_pubkey_load_ed25519(botan_pubkey_t* key,
+                              const uint8_t pubkey[32])
+   {
+#if defined(BOTAN_HAS_ED25519)
+   *key = nullptr;
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      const std::vector<uint8_t> pubkey_vec(pubkey, pubkey + 32);
+      *key = new botan_pubkey_struct(new Botan::Ed25519_PublicKey(pubkey_vec));
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   BOTAN_UNUSED(key, pubkey);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_ed25519_get_privkey(botan_privkey_t key,
+                                      uint8_t output[64])
+   {
+#if defined(BOTAN_HAS_ED25519)
+   return BOTAN_FFI_DO(Botan::Private_Key, key, k, {
+      if(Botan::Ed25519_PrivateKey* ed = dynamic_cast<Botan::Ed25519_PrivateKey*>(&k))
+         {
+         const Botan::secure_vector<uint8_t>& key = ed->get_private_key();
+         if(key.size() != 64)
+            return BOTAN_FFI_ERROR_INSUFFICIENT_BUFFER_SPACE;
+         Botan::copy_mem(output, key.data(), key.size());
+         return BOTAN_FFI_SUCCESS;
+         }
+      else
+         {
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
+         }
+      });
+#else
+   BOTAN_UNUSED(key, output);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_pubkey_ed25519_get_pubkey(botan_pubkey_t key,
+                                    uint8_t output[32])
+   {
+#if defined(BOTAN_HAS_ED25519)
+   return BOTAN_FFI_DO(Botan::Public_Key, key, k, {
+      if(Botan::Ed25519_PublicKey* ed = dynamic_cast<Botan::Ed25519_PublicKey*>(&k))
+         {
+         const std::vector<uint8_t>& key = ed->get_public_key();
+         if(key.size() != 32)
+            return BOTAN_FFI_ERROR_INSUFFICIENT_BUFFER_SPACE;
+         Botan::copy_mem(output, key.data(), key.size());
+         return BOTAN_FFI_SUCCESS;
+         }
+      else
+         {
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
+         }
+      });
+#else
+   BOTAN_UNUSED(key, output);
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_privkey_create_mceliece(botan_privkey_t* key_obj, botan_rng_t rng_obj, size_t n, size_t t)
+   {
+#if defined(BOTAN_HAS_MCELIECE)
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      if(key_obj == nullptr || rng_obj == nullptr || n == 0 || t == 0)
+         return BOTAN_FFI_ERROR_NULL_POINTER;
+
+      *key_obj = nullptr;
+
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+      std::unique_ptr<Botan::Private_Key> key(new Botan::McEliece_PrivateKey(rng, n, t));
+      *key_obj = new botan_privkey_struct(key.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+#else
+   return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+   }
+
+int botan_mceies_decrypt(botan_privkey_t mce_key_obj,
+                         const char* aead,
+                         const uint8_t ct[], size_t ct_len,
+                         const uint8_t ad[], size_t ad_len,
+                         uint8_t out[], size_t* out_len)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::Private_Key& key = safe_get(mce_key_obj);
+
+#if defined(BOTAN_HAS_MCELIECE) && defined(BOTAN_HAS_MCEIES)
+      Botan::McEliece_PrivateKey* mce = dynamic_cast<Botan::McEliece_PrivateKey*>(&key);
+      if(!mce)
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
+
+      const Botan::secure_vector<uint8_t> pt = mceies_decrypt(*mce, ct, ct_len, ad, ad_len, aead);
+      return write_vec_output(out, out_len, pt);
+#else
+      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+      });
+   }
+
+int botan_mceies_encrypt(botan_pubkey_t mce_key_obj,
+                         botan_rng_t rng_obj,
+                         const char* aead,
+                         const uint8_t pt[], size_t pt_len,
+                         const uint8_t ad[], size_t ad_len,
+                         uint8_t out[], size_t* out_len)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      Botan::Public_Key& key = safe_get(mce_key_obj);
+      Botan::RandomNumberGenerator& rng = safe_get(rng_obj);
+
+#if defined(BOTAN_HAS_MCELIECE) && defined(BOTAN_HAS_MCEIES)
+      Botan::McEliece_PublicKey* mce = dynamic_cast<Botan::McEliece_PublicKey*>(&key);
+      if(!mce)
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
+
+      Botan::secure_vector<uint8_t> ct = mceies_encrypt(*mce, pt, pt_len, ad, ad_len, rng, aead);
+      return write_vec_output(out, out_len, ct);
+#else
+      return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
+#endif
+      });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_rng.cpp b/src/lib/ffi/ffi_rng.cpp
new file mode 100644
index 000000000..68b4aaf64
--- /dev/null
+++ b/src/lib/ffi/ffi_rng.cpp
@@ -0,0 +1,53 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/ffi.h>
+#include <botan/internal/ffi_util.h>
+#include <botan/internal/ffi_rng.h>
+#include <botan/system_rng.h>
+#include <botan/auto_rng.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+int botan_rng_init(botan_rng_t* rng_out, const char* rng_type)
+   {
+   return ffi_guard_thunk(BOTAN_CURRENT_FUNCTION, [=]() {
+      BOTAN_ASSERT_ARG_NON_NULL(rng_out);
+
+      const std::string rng_type_s(rng_type ? rng_type : "system");
+
+      std::unique_ptr<Botan::RandomNumberGenerator> rng;
+
+      if(rng_type_s == "system")
+         rng.reset(new Botan::System_RNG);
+      else if(rng_type_s == "user")
+         rng.reset(new Botan::AutoSeeded_RNG);
+      else
+         return BOTAN_FFI_ERROR_BAD_PARAMETER;
+
+      *rng_out = new botan_rng_struct(rng.release());
+      return BOTAN_FFI_SUCCESS;
+      });
+   }
+
+int botan_rng_destroy(botan_rng_t rng)
+   {
+   return BOTAN_FFI_CHECKED_DELETE(rng);
+   }
+
+int botan_rng_get(botan_rng_t rng, uint8_t* out, size_t out_len)
+   {
+   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.randomize(out, out_len); });
+   }
+
+int botan_rng_reseed(botan_rng_t rng, size_t bits)
+   {
+   return BOTAN_FFI_DO(Botan::RandomNumberGenerator, rng, r, { r.reseed_from_rng(Botan::system_rng(), bits); });
+   }
+
+}
diff --git a/src/lib/ffi/ffi_rng.h b/src/lib/ffi/ffi_rng.h
new file mode 100644
index 000000000..73060eab7
--- /dev/null
+++ b/src/lib/ffi/ffi_rng.h
@@ -0,0 +1,21 @@
+/*
+* (C) 2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_FFI_RNG_H__
+#define BOTAN_FFI_RNG_H__
+
+#include <botan/rng.h>
+#include <botan/internal/ffi_util.h>
+
+extern "C" {
+
+using namespace Botan_FFI;
+
+BOTAN_FFI_DECLARE_STRUCT(botan_rng_struct, Botan::RandomNumberGenerator, 0x4901F9C1);
+
+}
+
+#endif
diff --git a/src/lib/ffi/ffi_util.h b/src/lib/ffi/ffi_util.h
new file mode 100644
index 000000000..919efdd75
--- /dev/null
+++ b/src/lib/ffi/ffi_util.h
@@ -0,0 +1,197 @@
+/*
+* (C) 2015,2017 Jack Lloyd
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#ifndef BOTAN_FFI_UTILS_H__
+#define BOTAN_FFI_UTILS_H__
+
+#include <cstdint>
+#include <memory>
+#include <stdexcept>
+#include <botan/exceptn.h>
+#include <botan/mem_ops.h>
+
+namespace Botan_FFI {
+
+#define BOTAN_ASSERT_ARG_NON_NULL(p) \
+   do { if(!p) throw Botan::Invalid_Argument("Argument " #p " is null"); } while(0)
+
+class FFI_Error : public Botan::Exception
+   {
+   public:
+      explicit FFI_Error(const std::string& what) : Exception("FFI error", what) {}
+   };
+
+template<typename T, uint32_t MAGIC>
+struct botan_struct
+   {
+   public:
+      botan_struct(T* obj) : m_magic(MAGIC), m_obj(obj) {}
+      ~botan_struct() { m_magic = 0; m_obj.reset(); }
+
+      bool magic_ok() const { return (m_magic == MAGIC); }
+
+      T* get() const
+         {
+         if(magic_ok() == false)
+            throw FFI_Error("Bad magic " + std::to_string(m_magic) +
+                            " in ffi object expected " + std::to_string(MAGIC));
+         return m_obj.get();
+         }
+   private:
+      uint32_t m_magic = 0;
+      std::unique_ptr<T> m_obj;
+   };
+
+#define BOTAN_FFI_DECLARE_STRUCT(NAME, TYPE, MAGIC) \
+   struct NAME : public botan_struct<TYPE, MAGIC> { explicit NAME(TYPE* x) : botan_struct(x) {} }
+
+// Declared in ffi.cpp
+int ffi_error_exception_thrown(const char* func_name, const char* exn);
+
+template<typename T, uint32_t M>
+T& safe_get(botan_struct<T,M>* p)
+   {
+   if(!p)
+      throw FFI_Error("Null pointer argument");
+   if(T* t = p->get())
+      return *t;
+   throw FFI_Error("Invalid object pointer");
+   }
+
+template<typename T, uint32_t M>
+const T& safe_get(const botan_struct<T,M>* p)
+   {
+   if(!p)
+      throw FFI_Error("Null pointer argument");
+   if(const T* t = p->get())
+      return *t;
+   throw FFI_Error("Invalid object pointer");
+   }
+
+template<typename Thunk>
+int ffi_guard_thunk(const char* func_name, Thunk thunk)
+   {
+   try
+      {
+      return thunk();
+      }
+   catch(std::bad_alloc)
+      {
+      return ffi_error_exception_thrown(func_name, "bad_alloc");
+      }
+   catch(std::exception& e)
+      {
+      return ffi_error_exception_thrown(func_name, e.what());
+      }
+   catch(...)
+      {
+      return ffi_error_exception_thrown(func_name, "unknown exception");
+      }
+
+   return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
+   }
+
+template<typename T, uint32_t M, typename F>
+int apply_fn(botan_struct<T, M>* o, const char* func_name, F func)
+   {
+   try
+      {
+      if(!o)
+         throw FFI_Error("Null object to " + std::string(func_name));
+      if(T* t = o->get())
+         return func(*t);
+      }
+   catch(std::bad_alloc)
+      {
+      return ffi_error_exception_thrown(func_name, "bad_alloc");
+      }
+   catch(std::exception& e)
+      {
+      return ffi_error_exception_thrown(func_name, e.what());
+      }
+   catch(...)
+      {
+      return ffi_error_exception_thrown(func_name, "unknown exception");
+      }
+
+   return BOTAN_FFI_ERROR_UNKNOWN_ERROR;
+   }
+
+#define BOTAN_FFI_DO(T, obj, param, block)                              \
+   apply_fn(obj, BOTAN_CURRENT_FUNCTION,                                \
+            [=](T& param) -> int { do { block } while(0); return BOTAN_FFI_SUCCESS; })
+
+template<typename T, uint32_t M>
+int ffi_delete_object(botan_struct<T, M>* obj, const char* func_name)
+   {
+   try
+      {
+      if(obj == nullptr)
+         return BOTAN_FFI_SUCCESS; // ignore delete of null objects
+
+      if(obj->magic_ok() == false)
+         return BOTAN_FFI_ERROR_INVALID_INPUT;
+
+      delete obj;
+      return BOTAN_FFI_SUCCESS;
+      }
+   catch(std::exception& e)
+      {
+      return ffi_error_exception_thrown(func_name, e.what());
+      }
+   catch(...)
+      {
+      return ffi_error_exception_thrown(func_name, "unknown exception");
+      }
+   }
+
+#define BOTAN_FFI_CHECKED_DELETE(o) ffi_delete_object(o, BOTAN_CURRENT_FUNCTION)
+
+inline int write_output(uint8_t out[], size_t* out_len, const uint8_t buf[], size_t buf_len)
+   {
+   const size_t avail = *out_len;
+   *out_len = buf_len;
+
+   if(avail >= buf_len)
+      {
+      Botan::copy_mem(out, buf, buf_len);
+      return BOTAN_FFI_SUCCESS;
+      }
+   else
+      {
+      Botan::clear_mem(out, avail);
+      return BOTAN_FFI_ERROR_INSUFFICIENT_BUFFER_SPACE;
+      }
+   }
+
+template<typename Alloc>
+int write_vec_output(uint8_t out[], size_t* out_len, const std::vector<uint8_t, Alloc>& buf)
+   {
+   return write_output(out, out_len, buf.data(), buf.size());
+   }
+
+inline int write_str_output(uint8_t out[], size_t* out_len, const std::string& str)
+   {
+   return write_output(out, out_len,
+                       reinterpret_cast<const uint8_t*>(str.c_str()),
+                       str.size() + 1);
+   }
+
+inline int write_str_output(char out[], size_t* out_len, const std::string& str)
+   {
+   return write_str_output(reinterpret_cast<uint8_t*>(out), out_len, str);
+   }
+
+inline int write_str_output(char out[], size_t* out_len, const std::vector<uint8_t>& str_vec)
+   {
+   return write_output(reinterpret_cast<uint8_t*>(out), out_len,
+                       reinterpret_cast<const uint8_t*>(str_vec.data()),
+                       str_vec.size());
+   }
+
+}
+
+#endif
diff --git a/src/lib/ffi/info.txt b/src/lib/ffi/info.txt
index 71b4e6cf9..a28df11b0 100644
--- a/src/lib/ffi/info.txt
+++ b/src/lib/ffi/info.txt
@@ -2,6 +2,17 @@
 FFI -> 20170327
 </defines>
 
+<header:internal>
+ffi_mp.h
+ffi_pkey.h
+ffi_rng.h
+ffi_util.h
+</header:internal>
+
+<header:public>
+ffi.h
+</header:public>
+
 <requires>
 aead
 kdf