mirror of
https://github.com/Lime3DS/Lime3DS
synced 2024-12-27 01:22:37 -06:00
UDS: Use the ToDS and FromDS fields to properly calculate the AAD used during encryption.
This commit is contained in:
parent
1f1739d366
commit
2eb174713b
1 changed files with 32 additions and 15 deletions
|
@ -103,7 +103,8 @@ static std::array<u8, CryptoPP::AES::BLOCKSIZE> GenerateDataCCMPKey(
|
|||
* Generates the Additional Authenticated Data (AAD) for an UDS 802.11 encrypted data frame.
|
||||
* @returns a buffer with the bytes of the AAD.
|
||||
*/
|
||||
static std::vector<u8> GenerateCCMPAAD(const MacAddress& sender, const MacAddress& receiver) {
|
||||
static std::vector<u8> GenerateCCMPAAD(const MacAddress& sender, const MacAddress& receiver,
|
||||
const MacAddress& bssid, u16 frame_control) {
|
||||
// Reference: IEEE 802.11-2007
|
||||
|
||||
// 8.3.3.3.2 Construct AAD (22-30 bytes)
|
||||
|
@ -113,20 +114,34 @@ static std::vector<u8> GenerateCCMPAAD(const MacAddress& sender, const MacAddres
|
|||
// Control field are masked to 0.
|
||||
struct {
|
||||
u16_be FC; // MPDU Frame Control field
|
||||
MacAddress receiver;
|
||||
MacAddress transmitter;
|
||||
MacAddress destination;
|
||||
MacAddress A1;
|
||||
MacAddress A2;
|
||||
MacAddress A3;
|
||||
u16_be SC; // MPDU Sequence Control field
|
||||
} aad_struct{};
|
||||
|
||||
// Default FC value of DataFrame | Protected | ToDS
|
||||
constexpr u16 DefaultFrameControl = 0x0841;
|
||||
|
||||
aad_struct.FC = DefaultFrameControl;
|
||||
constexpr u16 AADFrameControlMask = 0x8FC7;
|
||||
aad_struct.FC = frame_control & AADFrameControlMask;
|
||||
aad_struct.SC = 0;
|
||||
aad_struct.transmitter = sender;
|
||||
aad_struct.receiver = receiver;
|
||||
aad_struct.destination = receiver;
|
||||
|
||||
bool to_ds = (frame_control & (1 << 0)) != 0;
|
||||
bool from_ds = (frame_control & (1 << 1)) != 0;
|
||||
// In the 802.11 standard, ToDS = 1 and FromDS = 1 is a valid configuration,
|
||||
// however, the 3DS doesn't seem to transmit frames with such combination.
|
||||
ASSERT_MSG(to_ds != from_ds, "Invalid combination");
|
||||
|
||||
// The meaning of the address fields depends on the ToDS and FromDS fields.
|
||||
if (from_ds) {
|
||||
aad_struct.A1 = receiver;
|
||||
aad_struct.A2 = bssid;
|
||||
aad_struct.A3 = sender;
|
||||
}
|
||||
|
||||
if (to_ds) {
|
||||
aad_struct.A1 = bssid;
|
||||
aad_struct.A2 = sender;
|
||||
aad_struct.A3 = receiver;
|
||||
}
|
||||
|
||||
std::vector<u8> aad(sizeof(aad_struct));
|
||||
std::memcpy(aad.data(), &aad_struct, sizeof(aad_struct));
|
||||
|
@ -141,11 +156,12 @@ static std::vector<u8> GenerateCCMPAAD(const MacAddress& sender, const MacAddres
|
|||
static std::vector<u8> DecryptDataFrame(const std::vector<u8>& encrypted_payload,
|
||||
const std::array<u8, CryptoPP::AES::BLOCKSIZE>& ccmp_key,
|
||||
const MacAddress& sender, const MacAddress& receiver,
|
||||
u16 sequence_number) {
|
||||
const MacAddress& bssid, u16 sequence_number,
|
||||
u16 frame_control) {
|
||||
|
||||
// Reference: IEEE 802.11-2007
|
||||
|
||||
std::vector<u8> aad = GenerateCCMPAAD(sender, receiver);
|
||||
std::vector<u8> aad = GenerateCCMPAAD(sender, receiver, bssid, frame_control);
|
||||
|
||||
std::vector<u8> packet_number{0,
|
||||
0,
|
||||
|
@ -200,10 +216,11 @@ static std::vector<u8> DecryptDataFrame(const std::vector<u8>& encrypted_payload
|
|||
static std::vector<u8> EncryptDataFrame(const std::vector<u8>& payload,
|
||||
const std::array<u8, CryptoPP::AES::BLOCKSIZE>& ccmp_key,
|
||||
const MacAddress& sender, const MacAddress& receiver,
|
||||
u16 sequence_number) {
|
||||
const MacAddress& bssid, u16 sequence_number,
|
||||
u16 frame_control) {
|
||||
// Reference: IEEE 802.11-2007
|
||||
|
||||
std::vector<u8> aad = GenerateCCMPAAD(sender, receiver);
|
||||
std::vector<u8> aad = GenerateCCMPAAD(sender, receiver, bssid, frame_control);
|
||||
|
||||
std::vector<u8> packet_number{0,
|
||||
0,
|
||||
|
|
Loading…
Reference in a new issue