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Performance improvements

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* Remove option size memers on IP/TCP and instead calculate
these when they're needed
* Reorder members on IP/TCP so as to remove/decrease padding
* Move most memory helpers impl into header file so they
can be inlined
* Make PDUOption's move ctor/assignment operator noexcept
This commit is contained in:
Matias Fontanini
2017-05-13 16:21:18 -07:00
parent 8021112fea
commit fa85aa3f8b
7 changed files with 131 additions and 157 deletions
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36
src/ip.cpp
View File

@@ -73,14 +73,13 @@ IP::IP(address_type ip_dst, address_type ip_src) {
this->src_addr(ip_src);
}
IP::IP(const uint8_t* buffer, uint32_t total_sz)
: options_size_(0) {
IP::IP(const uint8_t* buffer, uint32_t total_sz) {
InputMemoryStream stream(buffer, total_sz);
stream.read(header_);
// Make sure we have enough size for options and not less than we should
if (head_len() * sizeof(uint32_t) > total_sz ||
head_len() * sizeof(uint32_t) < sizeof(header_)) {
if (TINS_UNLIKELY(head_len() * sizeof(uint32_t) > total_sz ||
head_len() * sizeof(uint32_t) < sizeof(header_))) {
throw malformed_packet();
}
const uint8_t* options_end = buffer + head_len() * sizeof(uint32_t);
@@ -108,7 +107,6 @@ IP::IP(const uint8_t* buffer, uint32_t total_sz)
else {
options_.push_back(option(opt_type));
}
options_size_ += option_size;
}
else if (opt_type == END) {
// If the end option found, we're done
@@ -120,10 +118,8 @@ IP::IP(const uint8_t* buffer, uint32_t total_sz)
}
else {
options_.push_back(option(opt_type));
options_size_++;
}
}
update_padded_options_size();
if (stream) {
// Don't avoid consuming more than we should if tot_len is 0,
// since this is the case when using TCP segmentation offload
@@ -171,8 +167,6 @@ void IP::init_ip_fields() {
header_.version = 4;
ttl(DEFAULT_TTL);
id(1);
options_size_ = 0;
padded_options_size_ = 0;
}
bool IP::is_fragmented() const {
@@ -321,18 +315,20 @@ uint16_t IP::stream_identifier() const {
}
void IP::add_option(const option& opt) {
internal_add_option(opt);
options_.push_back(opt);
}
void IP::update_padded_options_size() {
uint8_t padding = options_size_ % 4;
padded_options_size_ = padding ? (options_size_ - padding + 4) : options_size_;
uint32_t IP::calculate_options_size() const {
uint32_t options_size = 0;
for (options_type::const_iterator iter = options_.begin(); iter != options_.end(); ++iter) {
options_size += 1 + iter->data_size();
}
return options_size;
}
void IP::internal_add_option(const option& opt) {
options_size_ += static_cast<uint16_t>(1 + opt.data_size());
update_padded_options_size();
uint32_t IP::pad_options_size(uint32_t size) const {
uint8_t padding = size % 4;
return padding ? (size - padding + 4) : size;
}
bool IP::remove_option(option_identifier id) {
@@ -340,9 +336,7 @@ bool IP::remove_option(option_identifier id) {
if (iter == options_.end()) {
return false;
}
options_size_ -= static_cast<uint16_t>(1 + iter->data_size());
options_.erase(iter);
update_padded_options_size();
return true;
}
@@ -375,7 +369,7 @@ void IP::write_option(const option& opt, OutputMemoryStream& stream) {
// Virtual method overriding
uint32_t IP::header_size() const {
return sizeof(header_) + padded_options_size_;
return sizeof(header_) + pad_options_size(calculate_options_size());
}
PacketSender::SocketType pdu_type_to_sender_type(PDU::PDUType type) {
@@ -459,8 +453,10 @@ void IP::write_serialization(uint8_t* buffer, uint32_t total_sz) {
for (options_type::const_iterator it = options_.begin(); it != options_.end(); ++it) {
write_option(*it, stream);
}
const uint32_t options_size = calculate_options_size();
const uint32_t padded_options_size = pad_options_size(options_size);
// Add option padding
stream.fill(padded_options_size_ - options_size_, 0);
stream.fill(padded_options_size - options_size, 0);
uint32_t check = Utils::do_checksum(buffer, stream.pointer());
while (check >> 16) {

80
src/memory_helpers.cpp
View File

@@ -39,26 +39,6 @@ namespace Memory {
// InputMemoryStream
InputMemoryStream::InputMemoryStream(const uint8_t* buffer, size_t total_sz)
: buffer_(buffer), size_(total_sz) {
}
InputMemoryStream::InputMemoryStream(const vector<uint8_t>& data)
: buffer_(&data[0]), size_(data.size()) {
}
void InputMemoryStream::skip(size_t size) {
if (TINS_UNLIKELY(size > size_)) {
throw malformed_packet();
}
buffer_ += size;
size_ -= size;
}
bool InputMemoryStream::can_read(size_t byte_count) const {
return TINS_LIKELY(size_ >= byte_count);
}
void InputMemoryStream::read(vector<uint8_t>& value, size_t count) {
if (!can_read(count)) {
throw malformed_packet();
@@ -87,52 +67,8 @@ void InputMemoryStream::read(IPv6Address& address) {
skip(IPv6Address::address_size);
}
void InputMemoryStream::read(void* output_buffer, size_t output_buffer_size) {
if (!can_read(output_buffer_size)) {
throw malformed_packet();
}
read_data(buffer_, (uint8_t*)output_buffer, output_buffer_size);
skip(output_buffer_size);
}
const uint8_t* InputMemoryStream::pointer() const {
return buffer_;
}
size_t InputMemoryStream::size() const {
return size_;
}
void InputMemoryStream::size(size_t new_size) {
size_ = new_size;
}
InputMemoryStream::operator bool() const {
return size_ > 0;
}
// OutputMemoryStream
OutputMemoryStream::OutputMemoryStream(uint8_t* buffer, size_t total_sz)
: buffer_(buffer), size_(total_sz) {
}
OutputMemoryStream::OutputMemoryStream(vector<uint8_t>& buffer)
: buffer_(&buffer[0]), size_(buffer.size()) {
}
void OutputMemoryStream::skip(size_t size) {
if (TINS_UNLIKELY(size > size_)) {
throw malformed_packet();
}
buffer_ += size;
size_ -= size;
}
void OutputMemoryStream::write(const uint8_t* ptr, size_t length) {
write(ptr, ptr + length);
}
void OutputMemoryStream::write(const HWAddress<6>& address) {
write(address.begin(), address.end());
}
@@ -145,21 +81,5 @@ void OutputMemoryStream::write(const IPv6Address& address) {
write(address.begin(), address.end());
}
void OutputMemoryStream::fill(size_t size, uint8_t value) {
if (TINS_UNLIKELY(size_ < size)) {
throw serialization_error();
}
std::memset(buffer_, value, size);
skip(size);
}
uint8_t* OutputMemoryStream::pointer() {
return buffer_;
}
size_t OutputMemoryStream::size() const {
return size_;
}
} // Memory
} // Tins

55
src/tcp.cpp
View File

@@ -56,15 +56,14 @@ PDU::metadata TCP::extract_metadata(const uint8_t *buffer, uint32_t total_sz) {
}
TCP::TCP(uint16_t dport, uint16_t sport)
: header_(), options_size_(0), total_options_size_(0) {
: header_() {
this->dport(dport);
this->sport(sport);
data_offset(sizeof(tcp_header) / sizeof(uint32_t));
window(DEFAULT_WINDOW);
}
TCP::TCP(const uint8_t* buffer, uint32_t total_sz)
: options_size_(0), total_options_size_(0) {
TCP::TCP(const uint8_t* buffer, uint32_t total_sz) {
InputMemoryStream stream(buffer, total_sz);
stream.read(header_);
// Check that we have at least the amount of bytes we need and not less
@@ -74,6 +73,12 @@ TCP::TCP(const uint8_t* buffer, uint32_t total_sz)
}
const uint8_t* header_end = buffer + (data_offset() * sizeof(uint32_t));
if (stream.pointer() < header_end) {
// Estimate about 4 bytes per option and reserver that so we avoid doing
// multiple reallocations on the vector
options_.reserve((header_end - stream.pointer()) / sizeof(uint32_t));
}
while (stream.pointer() < header_end) {
const OptionTypes option_type = (OptionTypes)stream.read<uint8_t>();
if (option_type <= NOP) {
@@ -284,25 +289,26 @@ void TCP::flags(small_uint<12> value) {
void TCP::add_option(const option& opt) {
options_.push_back(opt);
internal_add_option(opt);
}
uint32_t TCP::header_size() const {
return sizeof(header_) + total_options_size_;
return sizeof(header_) + pad_options_size(calculate_options_size());
}
void TCP::write_serialization(uint8_t* buffer, uint32_t total_sz) {
OutputMemoryStream stream(buffer, total_sz);
const uint32_t options_size = calculate_options_size();
const uint32_t total_options_size = pad_options_size(options_size);
// Set checksum to 0, we'll calculate it at the end
checksum(0);
header_.doff = (sizeof(tcp_header) + total_options_size_) / sizeof(uint32_t);
header_.doff = (sizeof(tcp_header) + total_options_size) / sizeof(uint32_t);
stream.write(header_);
for (options_type::const_iterator it = options_.begin(); it != options_.end(); ++it) {
write_option(*it, stream);
}
if (options_size_ < total_options_size_) {
const uint16_t padding = total_options_size_ - options_size_;
if (options_size < total_options_size) {
const uint16_t padding = total_options_size - options_size;
stream.fill(padding, 1);
}
@@ -366,19 +372,23 @@ void TCP::write_option(const option& opt, OutputMemoryStream& stream) {
}
}
void TCP::update_options_size() {
uint8_t padding = options_size_ & 3;
total_options_size_ = (padding) ? (options_size_ - padding + 4) : options_size_;
uint32_t TCP::calculate_options_size() const {
uint32_t options_size = 0;
for (options_type::const_iterator iter = options_.begin(); iter != options_.end(); ++iter) {
const option& opt = *iter;
options_size += sizeof(uint8_t);
// SACK_OK contains length but not data
if (opt.data_size() || opt.option() == SACK_OK) {
options_size += sizeof(uint8_t);
options_size += static_cast<uint16_t>(opt.data_size());
}
}
return options_size;
}
void TCP::internal_add_option(const option& opt) {
options_size_ += sizeof(uint8_t);
// SACK_OK contains length but not data....
if (opt.data_size() || opt.option() == SACK_OK) {
options_size_ += sizeof(uint8_t);
options_size_ += static_cast<uint16_t>(opt.data_size());
}
update_options_size();
uint32_t TCP::pad_options_size(uint32_t size) const {
uint8_t padding = size & 3;
return padding ? (size - padding + 4) : size;
}
bool TCP::remove_option(OptionTypes type) {
@@ -386,14 +396,7 @@ bool TCP::remove_option(OptionTypes type) {
if (iter == options_.end()) {
return false;
}
options_size_ -= sizeof(uint8_t);
// SACK_OK contains length but not data....
if (iter->data_size() || iter->option() == SACK_OK) {
options_size_ -= sizeof(uint8_t);
options_size_ -= static_cast<uint16_t>(iter->data_size());
}
options_.erase(iter);
update_options_size();
return true;
}