1 // Copyright 2011 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef BASE_HASH_MD5_H_ 6 #define BASE_HASH_MD5_H_ 7 8 #include <string> 9 10 #include "base/base_export.h" 11 #include "base/strings/string_piece.h" 12 #include "build/build_config.h" 13 14 #if BUILDFLAG(IS_NACL) 15 #include "base/hash/md5_nacl.h" 16 #else 17 #include "base/hash/md5_boringssl.h" 18 #endif 19 20 // MD5 stands for Message Digest algorithm 5. 21 // MD5 is a robust hash function, designed for cyptography, but often used 22 // for file checksums. The code is complex and slow, but has few 23 // collisions. 24 // See Also: 25 // http://en.wikipedia.org/wiki/MD5 26 27 // These functions perform MD5 operations. The simplest call is MD5Sum() to 28 // generate the MD5 sum of the given data. 29 // 30 // You can also compute the MD5 sum of data incrementally by making multiple 31 // calls to MD5Update(): 32 // MD5Context ctx; // intermediate MD5 data: do not use 33 // MD5Init(&ctx); 34 // MD5Update(&ctx, data1, length1); 35 // MD5Update(&ctx, data2, length2); 36 // ... 37 // 38 // MD5Digest digest; // the result of the computation 39 // MD5Final(&digest, &ctx); 40 // 41 // You can call MD5DigestToBase16() to generate a string of the digest. 42 43 namespace base { 44 45 // Initializes the given MD5 context structure for subsequent calls to 46 // MD5Update(). 47 BASE_EXPORT void MD5Init(MD5Context* context); 48 49 // For the given buffer of |data| as a StringPiece, updates the given MD5 50 // context with the sum of the data. You can call this any number of times 51 // during the computation, except that MD5Init() must have been called first. 52 BASE_EXPORT void MD5Update(MD5Context* context, const StringPiece& data); 53 54 // Finalizes the MD5 operation and fills the buffer with the digest. 55 BASE_EXPORT void MD5Final(MD5Digest* digest, MD5Context* context); 56 57 // Converts a digest into human-readable hexadecimal. 58 BASE_EXPORT std::string MD5DigestToBase16(const MD5Digest& digest); 59 60 // Computes the MD5 sum of the given data buffer with the given length. 61 // The given 'digest' structure will be filled with the result data. 62 BASE_EXPORT void MD5Sum(const void* data, size_t length, MD5Digest* digest); 63 64 // Returns the MD5 (in hexadecimal) of a string. 65 BASE_EXPORT std::string MD5String(const StringPiece& str); 66 67 } // namespace base 68 69 #endif // BASE_HASH_MD5_H_ 70