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 "absl/strings/string_view.h" 20 #include "rtc_base/message_digest.h" 21 22 namespace rtc { 23 24 // An implementation of the digest class that uses OpenSSL. 25 class OpenSSLDigest final : public MessageDigest { 26 public: 27 // Creates an OpenSSLDigest with `algorithm` as the hash algorithm. 28 explicit OpenSSLDigest(absl::string_view algorithm); 29 ~OpenSSLDigest() override; 30 // Returns the digest output size (e.g. 16 bytes for MD5). 31 size_t Size() const override; 32 // Updates the digest with `len` bytes from `buf`. 33 void Update(const void* buf, size_t len) override; 34 // Outputs the digest value to `buf` with length `len`. 35 size_t Finish(void* buf, size_t len) override; 36 37 // Helper function to look up a digest's EVP by name. 38 static bool GetDigestEVP(absl::string_view algorithm, const EVP_MD** md); 39 // Helper function to look up a digest's name by EVP. 40 static bool GetDigestName(const EVP_MD* md, std::string* algorithm); 41 // Helper function to get the length of a digest. 42 static bool GetDigestSize(absl::string_view algorithm, size_t* len); 43 44 private: 45 EVP_MD_CTX* ctx_ = nullptr; 46 const EVP_MD* md_; 47 }; 48 49 } // namespace rtc 50 51 #endif // RTC_BASE_OPENSSL_DIGEST_H_ 52