1 /* 2 3 Copyright (c) 2003-2018, Arvid Norberg 4 All rights reserved. 5 6 Redistribution and use in source and binary forms, with or without 7 modification, are permitted provided that the following conditions 8 are met: 9 10 * Redistributions of source code must retain the above copyright 11 notice, this list of conditions and the following disclaimer. 12 * Redistributions in binary form must reproduce the above copyright 13 notice, this list of conditions and the following disclaimer in 14 the documentation and/or other materials provided with the distribution. 15 * Neither the name of the author nor the names of its 16 contributors may be used to endorse or promote products derived 17 from this software without specific prior written permission. 18 19 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 20 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 23 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 POSSIBILITY OF SUCH DAMAGE. 30 31 */ 32 33 #ifndef TORRENT_HASHER_HPP_INCLUDED 34 #define TORRENT_HASHER_HPP_INCLUDED 35 36 #include "libtorrent/config.hpp" 37 #include "libtorrent/sha1_hash.hpp" 38 #include "libtorrent/span.hpp" 39 40 #include <cstdint> 41 42 #include "libtorrent/aux_/disable_warnings_push.hpp" 43 #ifdef TORRENT_USE_LIBGCRYPT 44 #include <gcrypt.h> 45 46 #elif TORRENT_USE_COMMONCRYPTO 47 #include <CommonCrypto/CommonDigest.h> 48 49 #elif TORRENT_USE_CRYPTOAPI 50 #include "libtorrent/aux_/win_crypto_provider.hpp" 51 52 #elif defined TORRENT_USE_LIBCRYPTO 53 54 extern "C" { 55 #include <openssl/sha.h> 56 } 57 58 #else 59 #include "libtorrent/sha1.hpp" 60 #endif 61 #include "libtorrent/aux_/disable_warnings_pop.hpp" 62 63 namespace libtorrent { 64 65 // this is a SHA-1 hash class. 66 // 67 // You use it by first instantiating it, then call ``update()`` to feed it 68 // with data. i.e. you don't have to keep the entire buffer of which you want to 69 // create the hash in memory. You can feed the hasher parts of it at a time. When 70 // You have fed the hasher with all the data, you call ``final()`` and it 71 // will return the sha1-hash of the data. 72 // 73 // The constructor that takes a ``char const*`` and an integer will construct the 74 // sha1 context and feed it the data passed in. 75 // 76 // If you want to reuse the hasher object once you have created a hash, you have to 77 // call ``reset()`` to reinitialize it. 78 // 79 // The built-in software version of sha1-algorithm was implemented 80 // by Steve Reid and released as public domain. 81 // For more info, see ``src/sha1.cpp``. 82 class TORRENT_EXPORT hasher 83 { 84 public: 85 86 hasher(); 87 88 // this is the same as default constructing followed by a call to 89 // ``update(data, len)``. 90 hasher(char const* data, int len); 91 explicit hasher(span<char const> data); 92 hasher(hasher const&); 93 hasher& operator=(hasher const&) &; 94 95 // append the following bytes to what is being hashed 96 hasher& update(span<char const> data); 97 hasher& update(char const* data, int len); 98 99 // returns the SHA-1 digest of the buffers previously passed to 100 // update() and the hasher constructor. 101 sha1_hash final(); 102 103 // restore the hasher state to be as if the hasher has just been 104 // default constructed. 105 void reset(); 106 107 // hidden 108 ~hasher(); 109 110 private: 111 112 #ifdef TORRENT_USE_LIBGCRYPT 113 gcry_md_hd_t m_context; 114 #elif TORRENT_USE_COMMONCRYPTO 115 CC_SHA1_CTX m_context; 116 #elif TORRENT_USE_CRYPTOAPI 117 aux::crypt_hash<CALG_SHA1, PROV_RSA_FULL> m_context; 118 #elif defined TORRENT_USE_LIBCRYPTO 119 SHA_CTX m_context; 120 #else 121 sha1_ctx m_context; 122 #endif 123 }; 124 125 } 126 127 #endif // TORRENT_HASHER_HPP_INCLUDED 128