1 // Copyright (c) 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 // 5 // Some helpers for quic crypto 6 7 #ifndef NET_QUIC_CRYPTO_CRYPTO_UTILS_H_ 8 #define NET_QUIC_CRYPTO_CRYPTO_UTILS_H_ 9 10 #include <string> 11 12 #include "base/strings/string_piece.h" 13 #include "net/base/net_export.h" 14 #include "net/quic/crypto/crypto_handshake.h" 15 #include "net/quic/crypto/crypto_protocol.h" 16 #include "net/quic/quic_protocol.h" 17 #include "net/quic/quic_time.h" 18 19 namespace net { 20 21 class QuicTime; 22 class QuicRandom; 23 struct QuicCryptoNegotiatedParameters; 24 25 class NET_EXPORT_PRIVATE CryptoUtils { 26 public: 27 enum Perspective { 28 SERVER, 29 CLIENT, 30 }; 31 32 // Generates the connection nonce. The nonce is formed as: 33 // <4 bytes> current time 34 // <8 bytes> |orbit| (or random if |orbit| is empty) 35 // <20 bytes> random 36 static void GenerateNonce(QuicWallTime now, 37 QuicRandom* random_generator, 38 base::StringPiece orbit, 39 std::string* nonce); 40 41 // Returns true if the sni is valid, false otherwise. 42 // (1) disallow IP addresses; 43 // (2) check that the hostname contains valid characters only; and 44 // (3) contains at least one dot. 45 static bool IsValidSNI(base::StringPiece sni); 46 47 // Convert hostname to lowercase and remove the trailing '.'. 48 // Returns |hostname|. NormalizeHostname() doesn't support IP address 49 // literals. IsValidSNI() should be called before calling NormalizeHostname(). 50 static std::string NormalizeHostname(const char* hostname); 51 52 // DeriveKeys populates |crypters->encrypter|, |crypters->decrypter|, and 53 // |subkey_secret| (optional -- may be null) given the contents of 54 // |premaster_secret|, |client_nonce|, |server_nonce| and |hkdf_input|. |aead| 55 // determines which cipher will be used. |perspective| controls whether the 56 // server's keys are assigned to |encrypter| or |decrypter|. |server_nonce| is 57 // optional and, if non-empty, is mixed into the key derivation. 58 // |subkey_secret| will have the same length as |premaster_secret|. 59 static bool DeriveKeys(base::StringPiece premaster_secret, 60 QuicTag aead, 61 base::StringPiece client_nonce, 62 base::StringPiece server_nonce, 63 const std::string& hkdf_input, 64 Perspective perspective, 65 CrypterPair* crypters, 66 std::string* subkey_secret); 67 68 // Performs key extraction to derive a new secret of |result_len| bytes 69 // dependent on |subkey_secret|, |label|, and |context|. Returns false if the 70 // parameters are invalid (e.g. |label| contains null bytes); returns true on 71 // success. 72 static bool ExportKeyingMaterial(base::StringPiece subkey_secret, 73 base::StringPiece label, 74 base::StringPiece context, 75 size_t result_len, 76 std::string* result); 77 78 private: 79 DISALLOW_COPY_AND_ASSIGN(CryptoUtils); 80 }; 81 82 } // namespace net 83 84 #endif // NET_QUIC_CRYPTO_CRYPTO_UTILS_H_ 85