blob: dd9cfd9eb95a805f318e34c1ffa02fd800c9108a [file] [log] [blame]
// Copyright (c) 2012 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.
#include "quic/core/crypto/null_encrypter.h"
#include "absl/strings/string_view.h"
#include "quic/core/quic_data_writer.h"
#include "quic/core/quic_utils.h"
namespace quic {
const size_t kHashSizeShort = 12; // size of uint128 serialized short
NullEncrypter::NullEncrypter(Perspective perspective)
: perspective_(perspective) {}
bool NullEncrypter::SetKey(absl::string_view key) {
return key.empty();
}
bool NullEncrypter::SetNoncePrefix(absl::string_view nonce_prefix) {
return nonce_prefix.empty();
}
bool NullEncrypter::SetIV(absl::string_view iv) {
return iv.empty();
}
bool NullEncrypter::SetHeaderProtectionKey(absl::string_view key) {
return key.empty();
}
bool NullEncrypter::EncryptPacket(uint64_t /*packet_number*/,
absl::string_view associated_data,
absl::string_view plaintext,
char* output,
size_t* output_length,
size_t max_output_length) {
const size_t len = plaintext.size() + GetHashLength();
if (max_output_length < len) {
return false;
}
QuicUint128 hash;
if (perspective_ == Perspective::IS_SERVER) {
hash =
QuicUtils::FNV1a_128_Hash_Three(associated_data, plaintext, "Server");
} else {
hash =
QuicUtils::FNV1a_128_Hash_Three(associated_data, plaintext, "Client");
}
// TODO(ianswett): memmove required for in place encryption. Placing the
// hash at the end would allow use of memcpy, doing nothing for in place.
memmove(output + GetHashLength(), plaintext.data(), plaintext.length());
QuicUtils::SerializeUint128Short(hash,
reinterpret_cast<unsigned char*>(output));
*output_length = len;
return true;
}
std::string NullEncrypter::GenerateHeaderProtectionMask(
absl::string_view /*sample*/) {
return std::string(5, 0);
}
size_t NullEncrypter::GetKeySize() const {
return 0;
}
size_t NullEncrypter::GetNoncePrefixSize() const {
return 0;
}
size_t NullEncrypter::GetIVSize() const {
return 0;
}
size_t NullEncrypter::GetMaxPlaintextSize(size_t ciphertext_size) const {
return ciphertext_size - std::min(ciphertext_size, GetHashLength());
}
size_t NullEncrypter::GetCiphertextSize(size_t plaintext_size) const {
return plaintext_size + GetHashLength();
}
QuicPacketCount NullEncrypter::GetConfidentialityLimit() const {
return std::numeric_limits<QuicPacketCount>::max();
}
absl::string_view NullEncrypter::GetKey() const {
return absl::string_view();
}
absl::string_view NullEncrypter::GetNoncePrefix() const {
return absl::string_view();
}
size_t NullEncrypter::GetHashLength() const {
return kHashSizeShort;
}
} // namespace quic