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Add input memory stream class and port some PDUs to use it

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This commit is contained in:
Matias Fontanini
2015-12-24 15:21:07 -08:00
parent 6d90b0ce32
commit 13c05fbdb1
20 changed files with 408 additions and 295 deletions
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60
src/tcp.cpp
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@@ -38,17 +38,18 @@
#include "utils.h"
#include "exceptions.h"
#include "internals.h"
#include "memory_helpers.h"
using std::find_if;
using Tins::Memory::InputMemoryStream;
namespace Tins {
const uint16_t TCP::DEFAULT_WINDOW = 32678;
TCP::TCP(uint16_t dport, uint16_t sport)
: _options_size(0), _total_options_size(0)
: _tcp(), _options_size(0), _total_options_size(0)
{
std::memset(&_tcp, 0, sizeof(tcphdr));
this->dport(dport);
this->sport(sport);
data_offset(sizeof(tcphdr) / sizeof(uint32_t));
@@ -56,45 +57,54 @@ TCP::TCP(uint16_t dport, uint16_t sport)
}
TCP::TCP(const uint8_t *buffer, uint32_t total_sz)
: _options_size(0), _total_options_size(0)
{
if(total_sz < sizeof(tcphdr))
throw malformed_packet();
std::memcpy(&_tcp, buffer, sizeof(tcphdr));
if(data_offset() * sizeof(uint32_t) > total_sz || data_offset() * sizeof(uint32_t) < sizeof(tcphdr))
InputMemoryStream stream(buffer, total_sz);
stream.read(_tcp);
// Check that we have at least the amount of bytes we need and not less
if (TINS_UNLIKELY(data_offset() * sizeof(uint32_t) > total_sz ||
data_offset() * sizeof(uint32_t) < sizeof(tcphdr))) {
throw malformed_packet();
}
const uint8_t *header_end = buffer + (data_offset() * sizeof(uint32_t));
total_sz = static_cast<uint32_t>(total_sz - (header_end - buffer));
buffer += sizeof(tcphdr);
_total_options_size = 0;
_options_size = 0;
while(buffer < header_end) {
if(*buffer <= NOP) {
while (stream.pointer() < header_end) {
const OptionTypes option_type = (OptionTypes)stream.read<uint8_t>();
if (option_type <= NOP) {
#if TINS_IS_CXX11
add_option((OptionTypes)*buffer, 0);
add_option(option_type, 0);
#else
add_option(option((OptionTypes)*buffer, 0));
add_option(option(option_type, 0));
#endif // TINS_IS_CXX11
++buffer;
}
else {
if(buffer + 1 == header_end)
// Extract the length
uint32_t len = stream.read<uint8_t>();
const uint8_t *data_start = stream.pointer();
// We need to subtract the option type and length from the size
if (TINS_UNLIKELY(len < sizeof(uint8_t) << 1)) {
throw malformed_packet();
const uint8_t len = buffer[1] - (sizeof(uint8_t) << 1);
const uint8_t *data_start = buffer + 2;
if(data_start + len > header_end)
}
len -= (sizeof(uint8_t) << 1);
// Make sure we have enough bytes for the advertised option payload length
if (TINS_UNLIKELY(data_start + len > header_end)) {
throw malformed_packet();
}
// If we're using C++11, use the variadic template overload
#if TINS_IS_CXX11
add_option((OptionTypes)*buffer, data_start, data_start + len);
add_option(option_type, data_start, data_start + len);
#else
add_option(option((OptionTypes)*buffer, data_start, data_start + len));
add_option(option(option_type, data_start, data_start + len));
#endif // TINS_IS_CXX11
buffer = data_start + len;
// Skip the option's payload
stream.skip(len);
}
}
if(total_sz)
inner_pdu(new RawPDU(buffer, total_sz));
// If we still have any bytes left
if (stream) {
inner_pdu(new RawPDU(stream.pointer(), stream.size()));
}
}
void TCP::dport(uint16_t new_dport) {