libssh2 added to Miranda to support SFTP transfers in libcurl

1 files changed, 551 insertions, 0 deletions

diff --git a/libs/libssh2/src/wincng.h b/libs/libssh2/src/wincng.h
new file mode 100644
index 0000000000..5219db7f8a
--- /dev/null
+++ b/libs/libssh2/src/wincng.h
@@ -0,0 +1,551 @@
+/*
+ * Copyright (C) 2013-2015 Marc Hoersken <info@marc-hoersken.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms,
+ * with or without modification, are permitted provided
+ * that the following conditions are met:
+ *
+ *   Redistributions of source code must retain the above
+ *   copyright notice, this list of conditions and the
+ *   following disclaimer.
+ *
+ *   Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials
+ *   provided with the distribution.
+ *
+ *   Neither the name of the copyright holder nor the names
+ *   of any other contributors may be used to endorse or
+ *   promote products derived from this software without
+ *   specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ */
+
+/* required for cross-compilation against the w64 mingw-runtime package */
+#if defined(_WIN32_WINNT) && (_WIN32_WINNT < 0x0600)
+#undef _WIN32_WINNT
+#endif
+#ifndef _WIN32_WINNT
+#define _WIN32_WINNT 0x0600
+#endif
+
+#include <windows.h>
+#include <bcrypt.h>
+
+
+#define LIBSSH2_MD5 1
+
+#define LIBSSH2_HMAC_RIPEMD 0
+#define LIBSSH2_HMAC_SHA256 1
+#define LIBSSH2_HMAC_SHA512 1
+
+#define LIBSSH2_AES 1
+#define LIBSSH2_AES_CTR 0
+#define LIBSSH2_BLOWFISH 0
+#define LIBSSH2_RC4 1
+#define LIBSSH2_CAST 0
+#define LIBSSH2_3DES 1
+
+#define LIBSSH2_RSA 1
+#define LIBSSH2_DSA 1
+
+#define MD5_DIGEST_LENGTH 16
+#define SHA_DIGEST_LENGTH 20
+#define SHA256_DIGEST_LENGTH 32
+#define SHA512_DIGEST_LENGTH 64
+
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: Global context handles
+ */
+
+struct _libssh2_wincng_ctx {
+    BCRYPT_ALG_HANDLE hAlgRNG;
+    BCRYPT_ALG_HANDLE hAlgHashMD5;
+    BCRYPT_ALG_HANDLE hAlgHashSHA1;
+    BCRYPT_ALG_HANDLE hAlgHashSHA256;
+    BCRYPT_ALG_HANDLE hAlgHashSHA512;
+    BCRYPT_ALG_HANDLE hAlgHmacMD5;
+    BCRYPT_ALG_HANDLE hAlgHmacSHA1;
+    BCRYPT_ALG_HANDLE hAlgHmacSHA256;
+    BCRYPT_ALG_HANDLE hAlgHmacSHA512;
+    BCRYPT_ALG_HANDLE hAlgRSA;
+    BCRYPT_ALG_HANDLE hAlgDSA;
+    BCRYPT_ALG_HANDLE hAlgAES_CBC;
+    BCRYPT_ALG_HANDLE hAlgRC4_NA;
+    BCRYPT_ALG_HANDLE hAlg3DES_CBC;
+};
+
+struct _libssh2_wincng_ctx _libssh2_wincng;
+
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: Generic functions
+ */
+
+void _libssh2_wincng_init(void);
+void _libssh2_wincng_free(void);
+
+#define libssh2_crypto_init() \
+  _libssh2_wincng_init()
+#define libssh2_crypto_exit() \
+  _libssh2_wincng_free()
+
+#define _libssh2_random(buf, len) \
+  _libssh2_wincng_random(buf, len)
+
+#define libssh2_prepare_iovec(vec, len)  /* Empty. */
+
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: Hash structure
+ */
+
+typedef struct __libssh2_wincng_hash_ctx {
+    BCRYPT_HASH_HANDLE hHash;
+    unsigned char *pbHashObject;
+    unsigned long dwHashObject;
+    unsigned long cbHash;
+} _libssh2_wincng_hash_ctx;
+
+/*
+ * Windows CNG backend: Hash functions
+ */
+
+#define libssh2_sha1_ctx _libssh2_wincng_hash_ctx
+#define libssh2_sha1_init(ctx) \
+  (_libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHashSHA1, \
+                            SHA_DIGEST_LENGTH, NULL, 0) == 0)
+#define libssh2_sha1_update(ctx, data, datalen) \
+  _libssh2_wincng_hash_update(&ctx, (unsigned char *) data, datalen)
+#define libssh2_sha1_final(ctx, hash) \
+  _libssh2_wincng_hash_final(&ctx, hash)
+#define libssh2_sha1(data, datalen, hash) \
+  _libssh2_wincng_hash(data, datalen, _libssh2_wincng.hAlgHashSHA1, \
+                       hash, SHA_DIGEST_LENGTH)
+
+#define libssh2_sha256_ctx _libssh2_wincng_hash_ctx
+#define libssh2_sha256_init(ctx) \
+  (_libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHashSHA256, \
+                            SHA256_DIGEST_LENGTH, NULL, 0) == 0)
+#define libssh2_sha256_update(ctx, data, datalen) \
+  _libssh2_wincng_hash_update(&ctx, (unsigned char *) data, datalen)
+#define libssh2_sha256_final(ctx, hash) \
+  _libssh2_wincng_hash_final(&ctx, hash)
+#define libssh2_sha256(data, datalen, hash) \
+  _libssh2_wincng_hash(data, datalen, _libssh2_wincng.hAlgHashSHA256, \
+                       hash, SHA256_DIGEST_LENGTH)
+
+#define libssh2_sha512_ctx _libssh2_wincng_hash_ctx
+#define libssh2_sha512_init(ctx) \
+  (_libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHashSHA512, \
+                            SHA512_DIGEST_LENGTH, NULL, 0) == 0)
+#define libssh2_sha512_update(ctx, data, datalen) \
+  _libssh2_wincng_hash_update(&ctx, (unsigned char *) data, datalen)
+#define libssh2_sha512_final(ctx, hash) \
+  _libssh2_wincng_hash_final(&ctx, hash)
+#define libssh2_sha512(data, datalen, hash) \
+  _libssh2_wincng_hash(data, datalen, _libssh2_wincng.hAlgHashSHA512, \
+                       hash, SHA512_DIGEST_LENGTH)
+
+#define libssh2_md5_ctx _libssh2_wincng_hash_ctx
+#define libssh2_md5_init(ctx) \
+  (_libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHashMD5, \
+                            MD5_DIGEST_LENGTH, NULL, 0) == 0)
+#define libssh2_md5_update(ctx, data, datalen) \
+  _libssh2_wincng_hash_update(&ctx, (unsigned char *) data, datalen)
+#define libssh2_md5_final(ctx, hash) \
+  _libssh2_wincng_hash_final(&ctx, hash)
+#define libssh2_md5(data, datalen, hash) \
+  _libssh2_wincng_hash(data, datalen, _libssh2_wincng.hAlgHashMD5, \
+                       hash, MD5_DIGEST_LENGTH)
+
+/*
+ * Windows CNG backend: HMAC functions
+ */
+
+#define libssh2_hmac_ctx _libssh2_wincng_hash_ctx
+#define libssh2_hmac_ctx_init(ctx)
+#define libssh2_hmac_sha1_init(ctx, key, keylen) \
+  _libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHmacSHA1, \
+                            SHA_DIGEST_LENGTH, key, keylen)
+#define libssh2_hmac_md5_init(ctx, key, keylen) \
+  _libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHmacMD5, \
+                            MD5_DIGEST_LENGTH, key, keylen)
+#define libssh2_hmac_ripemd160_init(ctx, key, keylen)
+  /* not implemented */
+#define libssh2_hmac_sha256_init(ctx, key, keylen) \
+  _libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHmacSHA256, \
+                            SHA256_DIGEST_LENGTH, key, keylen)
+#define libssh2_hmac_sha512_init(ctx, key, keylen) \
+  _libssh2_wincng_hash_init(ctx, _libssh2_wincng.hAlgHmacSHA512, \
+                            SHA512_DIGEST_LENGTH, key, keylen)
+#define libssh2_hmac_update(ctx, data, datalen) \
+  _libssh2_wincng_hash_update(&ctx, (unsigned char *) data, datalen)
+#define libssh2_hmac_final(ctx, hash) \
+  _libssh2_wincng_hmac_final(&ctx, hash)
+#define libssh2_hmac_cleanup(ctx) \
+  _libssh2_wincng_hmac_cleanup(ctx)
+
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: Key Context structure
+ */
+
+typedef struct __libssh2_wincng_key_ctx {
+    BCRYPT_KEY_HANDLE hKey;
+    unsigned char *pbKeyObject;
+    unsigned long cbKeyObject;
+} _libssh2_wincng_key_ctx;
+
+
+/*
+ * Windows CNG backend: RSA functions
+ */
+
+#define libssh2_rsa_ctx _libssh2_wincng_key_ctx
+#define _libssh2_rsa_new(rsactx, e, e_len, n, n_len, \
+                         d, d_len, p, p_len, q, q_len, \
+                         e1, e1_len, e2, e2_len, c, c_len) \
+  _libssh2_wincng_rsa_new(rsactx, e, e_len, n, n_len, \
+                          d, d_len, p, p_len, q, q_len, \
+                          e1, e1_len, e2, e2_len, c, c_len)
+#define _libssh2_rsa_new_private(rsactx, s, filename, passphrase) \
+  _libssh2_wincng_rsa_new_private(rsactx, s, filename, passphrase)
+#define _libssh2_rsa_new_private_frommemory(rsactx, s, filedata, \
+                                            filedata_len, passphrase) \
+  _libssh2_wincng_rsa_new_private_frommemory(rsactx, s, filedata, \
+                                             filedata_len, passphrase)
+#define _libssh2_rsa_sha1_sign(s, rsactx, hash, hash_len, sig, sig_len) \
+  _libssh2_wincng_rsa_sha1_sign(s, rsactx, hash, hash_len, sig, sig_len)
+#define _libssh2_rsa_sha1_verify(rsactx, sig, sig_len, m, m_len) \
+  _libssh2_wincng_rsa_sha1_verify(rsactx, sig, sig_len, m, m_len)
+#define _libssh2_rsa_free(rsactx) \
+  _libssh2_wincng_rsa_free(rsactx)
+
+/*
+ * Windows CNG backend: DSA functions
+ */
+
+#define libssh2_dsa_ctx _libssh2_wincng_key_ctx
+#define _libssh2_dsa_new(dsactx, p, p_len, q, q_len, \
+                         g, g_len, y, y_len, x, x_len) \
+  _libssh2_wincng_dsa_new(dsactx, p, p_len, q, q_len, \
+                          g, g_len, y, y_len, x, x_len)
+#define _libssh2_dsa_new_private(dsactx, s, filename, passphrase) \
+  _libssh2_wincng_dsa_new_private(dsactx, s, filename, passphrase)
+#define _libssh2_dsa_new_private_frommemory(dsactx, s, filedata, \
+                                            filedata_len, passphrase) \
+  _libssh2_wincng_dsa_new_private_frommemory(dsactx, s, filedata, \
+                                             filedata_len, passphrase)
+#define _libssh2_dsa_sha1_sign(dsactx, hash, hash_len, sig) \
+  _libssh2_wincng_dsa_sha1_sign(dsactx, hash, hash_len, sig)
+#define _libssh2_dsa_sha1_verify(dsactx, sig, m, m_len) \
+  _libssh2_wincng_dsa_sha1_verify(dsactx, sig, m, m_len)
+#define _libssh2_dsa_free(dsactx) \
+  _libssh2_wincng_dsa_free(dsactx)
+
+/*
+ * Windows CNG backend: Key functions
+ */
+
+#define _libssh2_pub_priv_keyfile(s, m, m_len, p, p_len, pk, pw) \
+  _libssh2_wincng_pub_priv_keyfile(s, m, m_len, p, p_len, pk, pw)
+#define _libssh2_pub_priv_keyfilememory(s, m, m_len, p, p_len, \
+                                                     pk, pk_len, pw) \
+  _libssh2_wincng_pub_priv_keyfilememory(s, m, m_len, p, p_len, \
+                                                      pk, pk_len, pw)
+
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: Cipher Context structure
+ */
+
+struct _libssh2_wincng_cipher_ctx {
+    BCRYPT_KEY_HANDLE hKey;
+    unsigned char *pbKeyObject;
+    unsigned char *pbIV;
+    unsigned long dwKeyObject;
+    unsigned long dwIV;
+    unsigned long dwBlockLength;
+};
+
+#define _libssh2_cipher_ctx struct _libssh2_wincng_cipher_ctx
+
+/*
+ * Windows CNG backend: Cipher Type structure
+ */
+
+struct _libssh2_wincng_cipher_type {
+    BCRYPT_ALG_HANDLE *phAlg;
+    unsigned long dwKeyLength;
+    unsigned long dwUseIV;
+};
+
+#define _libssh2_cipher_type(type) struct _libssh2_wincng_cipher_type type
+
+#define _libssh2_cipher_aes256ctr { NULL, 32, 1 } /* not supported */
+#define _libssh2_cipher_aes192ctr { NULL, 24, 1 } /* not supported */
+#define _libssh2_cipher_aes128ctr { NULL, 16, 1 } /* not supported */
+#define _libssh2_cipher_aes256 { &_libssh2_wincng.hAlgAES_CBC, 32, 1 }
+#define _libssh2_cipher_aes192 { &_libssh2_wincng.hAlgAES_CBC, 24, 1 }
+#define _libssh2_cipher_aes128 { &_libssh2_wincng.hAlgAES_CBC, 16, 1 }
+#define _libssh2_cipher_blowfish { NULL, 16, 0 } /* not supported */
+#define _libssh2_cipher_arcfour { &_libssh2_wincng.hAlgRC4_NA, 16, 0 }
+#define _libssh2_cipher_cast5 { NULL, 16, 0 } /* not supported */
+#define _libssh2_cipher_3des { &_libssh2_wincng.hAlg3DES_CBC, 24, 1 }
+
+/*
+ * Windows CNG backend: Cipher functions
+ */
+
+#define _libssh2_cipher_init(ctx, type, iv, secret, encrypt) \
+  _libssh2_wincng_cipher_init(ctx, type, iv, secret, encrypt)
+#define _libssh2_cipher_crypt(ctx, type, encrypt, block, blocklen) \
+  _libssh2_wincng_cipher_crypt(ctx, type, encrypt, block, blocklen)
+#define _libssh2_cipher_dtor(ctx) \
+  _libssh2_wincng_cipher_dtor(ctx)
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: BigNumber Context
+ */
+
+#define _libssh2_bn_ctx int /* not used */
+#define _libssh2_bn_ctx_new() 0 /* not used */
+#define _libssh2_bn_ctx_free(bnctx) ((void)0) /* not used */
+
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: BigNumber structure
+ */
+
+struct _libssh2_wincng_bignum {
+    unsigned char *bignum;
+    unsigned long length;
+};
+
+#define _libssh2_bn struct _libssh2_wincng_bignum
+
+/*
+ * Windows CNG backend: BigNumber functions
+ */
+
+_libssh2_bn *_libssh2_wincng_bignum_init(void);
+
+#define _libssh2_bn_init() \
+  _libssh2_wincng_bignum_init()
+#define _libssh2_bn_init_from_bin() \
+  _libssh2_bn_init()
+#define _libssh2_bn_rand(bn, bits, top, bottom) \
+  _libssh2_wincng_bignum_rand(bn, bits, top, bottom)
+#define _libssh2_bn_mod_exp(r, a, p, m, ctx) \
+  _libssh2_wincng_bignum_mod_exp(r, a, p, m, ctx)
+#define _libssh2_bn_set_word(bn, word) \
+  _libssh2_wincng_bignum_set_word(bn, word)
+#define _libssh2_bn_from_bin(bn, len, bin) \
+  _libssh2_wincng_bignum_from_bin(bn, len, bin)
+#define _libssh2_bn_to_bin(bn, bin) \
+  _libssh2_wincng_bignum_to_bin(bn, bin)
+#define _libssh2_bn_bytes(bn) bn->length
+#define _libssh2_bn_bits(bn) \
+  _libssh2_wincng_bignum_bits(bn)
+#define _libssh2_bn_free(bn) \
+  _libssh2_wincng_bignum_free(bn)
+
+/*******************************************************************/
+/*
+ * Windows CNG backend: forward declarations
+ */
+void _libssh2_wincng_init(void);
+void _libssh2_wincng_free(void);
+int _libssh2_wincng_random(void *buf, int len);
+void _libssh2_init_aes_ctr(void);
+
+int
+_libssh2_wincng_hash_init(_libssh2_wincng_hash_ctx *ctx,
+                          BCRYPT_ALG_HANDLE hAlg, unsigned long hashlen,
+                          unsigned char *key, unsigned long keylen);
+int
+_libssh2_wincng_hash_update(_libssh2_wincng_hash_ctx *ctx,
+                            const unsigned char *data, unsigned long datalen);
+int
+_libssh2_wincng_hash_final(_libssh2_wincng_hash_ctx *ctx,
+                           unsigned char *hash);
+int
+_libssh2_wincng_hash(unsigned char *data, unsigned long datalen,
+                     BCRYPT_ALG_HANDLE hAlg,
+                     unsigned char *hash, unsigned long hashlen);
+
+int
+_libssh2_wincng_hmac_final(_libssh2_wincng_hash_ctx *ctx,
+                           unsigned char *hash);
+void
+_libssh2_wincng_hmac_cleanup(_libssh2_wincng_hash_ctx *ctx);
+
+int
+_libssh2_wincng_key_sha1_verify(_libssh2_wincng_key_ctx *ctx,
+                                const unsigned char *sig,
+                                unsigned long sig_len,
+                                const unsigned char *m,
+                                unsigned long m_len,
+                                unsigned long flags);
+
+int
+_libssh2_wincng_rsa_new(libssh2_rsa_ctx **rsa,
+                        const unsigned char *edata,
+                        unsigned long elen,
+                        const unsigned char *ndata,
+                        unsigned long nlen,
+                        const unsigned char *ddata,
+                        unsigned long dlen,
+                        const unsigned char *pdata,
+                        unsigned long plen,
+                        const unsigned char *qdata,
+                        unsigned long qlen,
+                        const unsigned char *e1data,
+                        unsigned long e1len,
+                        const unsigned char *e2data,
+                        unsigned long e2len,
+                        const unsigned char *coeffdata,
+                        unsigned long coefflen);
+int
+_libssh2_wincng_rsa_new_private(libssh2_rsa_ctx **rsa,
+                                LIBSSH2_SESSION *session,
+                                const char *filename,
+                                const unsigned char *passphrase);
+int
+_libssh2_wincng_rsa_new_private_frommemory(libssh2_rsa_ctx **rsa,
+                                           LIBSSH2_SESSION *session,
+                                           const char *filedata,
+                                           size_t filedata_len,
+                                           unsigned const char *passphrase);
+int
+_libssh2_wincng_rsa_sha1_verify(libssh2_rsa_ctx *rsa,
+                                const unsigned char *sig,
+                                unsigned long sig_len,
+                                const unsigned char *m,
+                                unsigned long m_len);
+int
+_libssh2_wincng_rsa_sha1_sign(LIBSSH2_SESSION *session,
+                              libssh2_rsa_ctx *rsa,
+                              const unsigned char *hash,
+                              size_t hash_len,
+                              unsigned char **signature,
+                              size_t *signature_len);
+void
+_libssh2_wincng_rsa_free(libssh2_rsa_ctx *rsa);
+
+#if LIBSSH2_DSA
+int
+_libssh2_wincng_dsa_new(libssh2_dsa_ctx **dsa,
+                        const unsigned char *pdata,
+                        unsigned long plen,
+                        const unsigned char *qdata,
+                        unsigned long qlen,
+                        const unsigned char *gdata,
+                        unsigned long glen,
+                        const unsigned char *ydata,
+                        unsigned long ylen,
+                        const unsigned char *xdata,
+                        unsigned long xlen);
+int
+_libssh2_wincng_dsa_new_private(libssh2_dsa_ctx **dsa,
+                                LIBSSH2_SESSION *session,
+                                const char *filename,
+                                const unsigned char *passphrase);
+int
+_libssh2_wincng_dsa_new_private_frommemory(libssh2_dsa_ctx **dsa,
+                                           LIBSSH2_SESSION *session,
+                                           const char *filedata,
+                                           size_t filedata_len,
+                                           unsigned const char *passphrase);
+int
+_libssh2_wincng_dsa_sha1_verify(libssh2_dsa_ctx *dsa,
+                                const unsigned char *sig_fixed,
+                                const unsigned char *m,
+                                unsigned long m_len);
+int
+_libssh2_wincng_dsa_sha1_sign(libssh2_dsa_ctx *dsa,
+                              const unsigned char *hash,
+                              unsigned long hash_len,
+                              unsigned char *sig_fixed);
+void
+_libssh2_wincng_dsa_free(libssh2_dsa_ctx *dsa);
+#endif
+
+int
+_libssh2_wincng_pub_priv_keyfile(LIBSSH2_SESSION *session,
+                                 unsigned char **method,
+                                 size_t *method_len,
+                                 unsigned char **pubkeydata,
+                                 size_t *pubkeydata_len,
+                                 const char *privatekey,
+                                 const char *passphrase);
+int
+_libssh2_wincng_pub_priv_keyfilememory(LIBSSH2_SESSION *session,
+                                       unsigned char **method,
+                                       size_t *method_len,
+                                       unsigned char **pubkeydata,
+                                       size_t *pubkeydata_len,
+                                       const char *privatekeydata,
+                                       size_t privatekeydata_len,
+                                       const char *passphrase);
+
+int
+_libssh2_wincng_cipher_init(_libssh2_cipher_ctx *ctx,
+                            _libssh2_cipher_type(type),
+                            unsigned char *iv,
+                            unsigned char *secret,
+                            int encrypt);
+int
+_libssh2_wincng_cipher_crypt(_libssh2_cipher_ctx *ctx,
+                             _libssh2_cipher_type(type),
+                             int encrypt,
+                             unsigned char *block,
+                             size_t blocklen);
+void
+_libssh2_wincng_cipher_dtor(_libssh2_cipher_ctx *ctx);
+
+_libssh2_bn *
+_libssh2_wincng_bignum_init(void);
+int
+_libssh2_wincng_bignum_rand(_libssh2_bn *rnd, int bits, int top, int bottom);
+int
+_libssh2_wincng_bignum_mod_exp(_libssh2_bn *r,
+                               _libssh2_bn *a,
+                               _libssh2_bn *p,
+                               _libssh2_bn *m,
+                               _libssh2_bn_ctx *bnctx);
+int
+_libssh2_wincng_bignum_set_word(_libssh2_bn *bn, unsigned long word);
+unsigned long
+_libssh2_wincng_bignum_bits(const _libssh2_bn *bn);
+void
+_libssh2_wincng_bignum_from_bin(_libssh2_bn *bn, unsigned long len,
+                                const unsigned char *bin);
+void
+_libssh2_wincng_bignum_to_bin(const _libssh2_bn *bn, unsigned char *bin);
+void
+_libssh2_wincng_bignum_free(_libssh2_bn *bn);