// Copyright (c) 2011 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef NET_CERT_PEM_H_ #define NET_CERT_PEM_H_ #include #include #include #include "base/strings/string_piece.h" #include "net/base/net_export.h" namespace net { // PEMTokenizer is a utility class for the parsing of data encapsulated // using RFC 1421, Privacy Enhancement for Internet Electronic Mail. It // does not implement the full specification, most notably it does not // support the Encapsulated Header Portion described in Section 4.4. class NET_EXPORT_PRIVATE PEMTokenizer { public: // Create a new PEMTokenizer that iterates through |str| searching for // instances of PEM encoded blocks that are of the |allowed_block_types|. // |str| must remain valid for the duration of the PEMTokenizer. PEMTokenizer(const base::StringPiece& str, const std::vector& allowed_block_types); PEMTokenizer(const PEMTokenizer&) = delete; PEMTokenizer& operator=(const PEMTokenizer&) = delete; ~PEMTokenizer(); // Attempts to decode the next PEM block in the string. Returns false if no // PEM blocks can be decoded. The decoded PEM block will be available via // data(). bool GetNext(); // Returns the PEM block type (eg: CERTIFICATE) of the last successfully // decoded PEM block. // GetNext() must have returned true before calling this method. const std::string& block_type() const { return block_type_; } // Returns the raw, Base64-decoded data of the last successfully decoded // PEM block. // GetNext() must have returned true before calling this method. const std::string& data() const { return data_; } private: void Init(const base::StringPiece& str, const std::vector& allowed_block_types); // A simple cache of the allowed PEM header and footer for a given PEM // block type, so that it is only computed once. struct PEMType; // The string to search, which must remain valid for as long as this class // is around. base::StringPiece str_; // The current position within |str_| that searching should begin from, // or StringPiece::npos if iteration is complete base::StringPiece::size_type pos_; // The type of data that was encoded, as indicated in the PEM // Pre-Encapsulation Boundary (eg: CERTIFICATE, PKCS7, or // PRIVACY-ENHANCED MESSAGE). std::string block_type_; // The types of PEM blocks that are allowed. PEM blocks that are not of // one of these types will be skipped. std::vector block_types_; // The raw (Base64-decoded) data of the last successfully decoded block. std::string data_; }; // Encodes |data| in the encapsulated message format described in RFC 1421, // with |type| as the PEM block type (eg: CERTIFICATE). NET_EXPORT_PRIVATE std::string PEMEncode(base::StringPiece data, const std::string& type); } // namespace net #endif // NET_CERT_PEM_H_