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 #include "quiche/quic/core/crypto/aes_base_decrypter.h" 6 7 #include "absl/strings/string_view.h" 8 #include "openssl/aes.h" 9 #include "quiche/quic/platform/api/quic_bug_tracker.h" 10 11 namespace quic { 12 SetHeaderProtectionKey(absl::string_view key)13bool AesBaseDecrypter::SetHeaderProtectionKey(absl::string_view key) { 14 if (key.size() != GetKeySize()) { 15 QUIC_BUG(quic_bug_10649_1) << "Invalid key size for header protection"; 16 return false; 17 } 18 if (AES_set_encrypt_key(reinterpret_cast<const uint8_t*>(key.data()), 19 key.size() * 8, &pne_key_) != 0) { 20 QUIC_BUG(quic_bug_10649_2) << "Unexpected failure of AES_set_encrypt_key"; 21 return false; 22 } 23 return true; 24 } 25 GenerateHeaderProtectionMask(QuicDataReader * sample_reader)26std::string AesBaseDecrypter::GenerateHeaderProtectionMask( 27 QuicDataReader* sample_reader) { 28 absl::string_view sample; 29 if (!sample_reader->ReadStringPiece(&sample, AES_BLOCK_SIZE)) { 30 return std::string(); 31 } 32 std::string out(AES_BLOCK_SIZE, 0); 33 AES_encrypt(reinterpret_cast<const uint8_t*>(sample.data()), 34 reinterpret_cast<uint8_t*>(const_cast<char*>(out.data())), 35 &pne_key_); 36 return out; 37 } 38 GetIntegrityLimit() const39QuicPacketCount AesBaseDecrypter::GetIntegrityLimit() const { 40 // For AEAD_AES_128_GCM ... endpoints that do not attempt to remove 41 // protection from packets larger than 2^11 bytes can attempt to remove 42 // protection from at most 2^57 packets. 43 // For AEAD_AES_256_GCM [the limit] is substantially larger than the limit for 44 // AEAD_AES_128_GCM. However, this document recommends that the same limit be 45 // applied to both functions as either limit is acceptably large. 46 // https://quicwg.org/base-drafts/draft-ietf-quic-tls.html#name-integrity-limit 47 static_assert(kMaxIncomingPacketSize <= 2048, 48 "This key limit requires limits on decryption payload sizes"); 49 return 144115188075855872U; 50 } 51 52 } // namespace quic 53