method_defrag: Merge EAP response/request flags

Signed-off-by: Simon Rozman <simon@rozman.si>
This commit is contained in:
Simon Rozman 2020-01-22 09:51:17 +01:00
parent b908ff3aa9
commit 0daa0579fe
2 changed files with 14 additions and 23 deletions

View File

@ -51,28 +51,19 @@ namespace eap
#pragma warning(disable: 4480)
///
/// EAP-(T)TLS/PEAP request packet flags
/// EAP-(T)TLS/PEAP request/response packet flags
///
/// \sa [The EAP-TLS Authentication Protocol (Chapter: 3.1 EAP-TLS Request Packet)](https://tools.ietf.org/html/rfc5216#section-3.1)
/// \sa [The EAP-TTLS Authentication Protocol Version 0 (Chapter: 9.1. Packet Format)](https://tools.ietf.org/html/rfc5281#section-9.1)
///
enum flags_req_t : unsigned char {
flags_req_length_incl = 0x80, ///< Length included
flags_req_more_frag = 0x40, ///< More fragments
flags_req_start = 0x20, ///< Start
flags_req_ver_mask = 0x07, ///< Version mask
};
///
/// EAP-(T)TLS/PEAP response packet flags
///
/// \sa [The EAP-TLS Authentication Protocol (Chapter: 3.2 EAP-TLS Response Packet)](https://tools.ietf.org/html/rfc5216#section-3.2)
/// \sa [The EAP-TTLS Authentication Protocol Version 0 (Chapter: 9.1. Packet Format)](https://tools.ietf.org/html/rfc5281#section-9.1)
/// \sa [Protected EAP Protocol (PEAP) Version 2 (Chapter: 3.2. PEAPv2 Packet Format)](https://tools.ietf.org/html/draft-josefsson-pppext-eap-tls-eap-10#section-3.2)
///
enum flags_res_t : unsigned char {
flags_res_length_incl = 0x80, ///< Length included
flags_res_more_frag = 0x40, ///< More fragments
flags_res_ver_mask = 0x07, ///< Version mask
enum flags_t : unsigned char {
flags_length_incl = 0x80, ///< Length included
flags_more_frag = 0x40, ///< More fragments
flags_start = 0x20, ///< Start
flags_tls_length_incl = 0x10, ///< TLS Length included
flags_ver_mask = 0x07, ///< Version mask
};
#pragma warning(pop)

View File

@ -64,7 +64,7 @@ EapPeerMethodResponseAction eap::method_defrag::process_request_packet(
auto data_packet = reinterpret_cast<const unsigned char*>(pReceivedPacket);
// To prevent version downgrade attacks, negotiate protocol version on binding exchange only. Then stick to it!
unsigned char data_version = data_packet[0] & flags_req_ver_mask;
unsigned char data_version = data_packet[0] & flags_ver_mask;
if (m_phase == phase_t::init) {
m_version = min<unsigned char>(data_version, m_version);
m_module.log_event(&EAPMETHOD_DEFRAG_VERSION,
@ -77,16 +77,16 @@ EapPeerMethodResponseAction eap::method_defrag::process_request_packet(
// Get packet content pointers for more readable code later on.
auto
data_content = data_packet + (data_packet[0] & flags_req_length_incl ? 5 : 1),
data_content = data_packet + (data_packet[0] & flags_length_incl ? 5 : 1),
data_content_end = data_packet + dwReceivedPacketSize;
if (data_content > data_content_end)
throw win_runtime_error(EAP_E_EAPHOST_METHOD_INVALID_PACKET, __FUNCTION__ " Incomplete data.");
// Do the defragmentation.
if (data_packet[0] & flags_req_more_frag) {
if (data_packet[0] & flags_more_frag) {
if (m_data_req.empty()) {
// Start a new packet.
if (data_packet[0] & flags_req_length_incl) {
if (data_packet[0] & flags_length_incl) {
// Preallocate data according to the Length field.
m_data_req.reserve(ntohl(*reinterpret_cast<const unsigned int*>(data_packet + 1)));
}
@ -107,7 +107,7 @@ EapPeerMethodResponseAction eap::method_defrag::process_request_packet(
if (m_send_res) {
// We are sending a fragmented message.
if (m_data_req.empty() && (data_packet[0] & (flags_req_length_incl | flags_req_more_frag | flags_req_start)) == 0) {
if (m_data_req.empty() && (data_packet[0] & (flags_length_incl | flags_more_frag | flags_start)) == 0) {
// Received packet is the ACK of our fragmented message packet. Send the next fragment.
return EapPeerMethodResponseActionSend;
} else
@ -140,7 +140,7 @@ void eap::method_defrag::get_response_packet(
packet.clear();
if (size_data + 1 > size_max) {
// Write one fragment.
packet.push_back(flags_res_length_incl | flags_res_more_frag | m_version);
packet.push_back(flags_length_incl | flags_more_frag | m_version);
unsigned int length = htonl((unsigned int)size_data);
packet.insert(packet.end(), reinterpret_cast<const unsigned char*>(&length), reinterpret_cast<const unsigned char*>(&length + 1));
auto data_begin = m_data_res.begin() + 0, data_end = data_begin + (size_max - 5);