1 /* 2 * Copyright 2004 The WebRTC Project Authors. All rights reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 #ifndef RTC_BASE_OPENSSL_DIGEST_H_ 12 #define RTC_BASE_OPENSSL_DIGEST_H_ 13 14 #include <openssl/ossl_typ.h> 15 #include <stddef.h> 16 17 #include <string> 18 19 #include "rtc_base/message_digest.h" 20 21 namespace rtc { 22 23 // An implementation of the digest class that uses OpenSSL. 24 class OpenSSLDigest final : public MessageDigest { 25 public: 26 // Creates an OpenSSLDigest with |algorithm| as the hash algorithm. 27 explicit OpenSSLDigest(const std::string& algorithm); 28 ~OpenSSLDigest() override; 29 // Returns the digest output size (e.g. 16 bytes for MD5). 30 size_t Size() const override; 31 // Updates the digest with |len| bytes from |buf|. 32 void Update(const void* buf, size_t len) override; 33 // Outputs the digest value to |buf| with length |len|. 34 size_t Finish(void* buf, size_t len) override; 35 36 // Helper function to look up a digest's EVP by name. 37 static bool GetDigestEVP(const std::string& algorithm, const EVP_MD** md); 38 // Helper function to look up a digest's name by EVP. 39 static bool GetDigestName(const EVP_MD* md, std::string* algorithm); 40 // Helper function to get the length of a digest. 41 static bool GetDigestSize(const std::string& algorithm, size_t* len); 42 43 private: 44 EVP_MD_CTX* ctx_ = nullptr; 45 const EVP_MD* md_; 46 }; 47 48 } // namespace rtc 49 50 #endif // RTC_BASE_OPENSSL_DIGEST_H_ 51