leviathan/KAT
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

closer

Browse Source
This commit is contained in:
leviathan
2026-02-13 21:46:04 -05:00
parent 04b1d91d78
commit b306ff0574
134 changed files with 4060 additions and 458 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/protocols/vag.rs
+40 -35
View File
@@ -1,15 +1,18 @@
//! VAG (VW/Audi/Seat/Skoda) protocol decoder/encoder
//!
//! Aligned with ProtoPirate reference: `REFERENCES/ProtoPirate/protocols/vag.c`.
//! Decode/encode logic (steps, Type 1/2/3/4, AUT64/TEA, dispatch, gap 6000µs) matches reference.
//! Reset/Preamble2/Sync2/Data2 use reference thresholds (79/80, 380-620/880-1120µs).
//! Preamble1/Data1 use TE_DELTA_12 80 (ref 79/80).
//! Aligned with ProtoPirate reference: `REFERENCES/ProtoPirate/protocols/vag.c` and `vag.h`.
//! Decoder steps (VAGDecoderStepReset/Preamble1/Data1/Preamble2/Sync2A/B/C/Data2), Type 1/2/3/4
//! parse (vag_parse_data, vag_aut64_decrypt, vag_tea_decrypt), dispatch (0x2A/0x1C/0x46 and
//! 0x2B/0x1D/0x47), and encoder (vag_encoder_build_type1/2/3_4) match the reference.
//!
//! Protocol characteristics:
//! - Manchester encoding; 80 bits (key1 64 + key2 16)
//! - Type 1/2: 300/600µs, prefix 0x2F3F (AUT64) / 0x2F1C (TEA), dispatch 0x2A/0x1C/0x46
//! - Type 3/4: 500/1000µs, preamble 41+ pairs, sync 1000µs + 3×750µs, dispatch 0x2B/0x1D/0x47
//! - End-of-data gap 6000µs (accept within 4000µs); keys from keystore (VAG raw 64 bytes)
//! **Timing**: Reference uses VAG_TOL_300 (79) and VAG_TOL_500 (120). Reset/Preamble1 use 300±79/80;
//! Preamble1→Data1 gap 600µs ±79; Data1 short 300±79/80, long 600±79/80; end-of-data gap 6000µs
//! (accept diff < 4000). Preamble2 count 500±80; Sync2A 500/1000µs ±79; Sync2B 750µs ±79;
//! Sync2C 750µs ±79; Data2 short 500±120 (380–620µs), long 1000±120 (880–1120µs).
//!
//! **Protocol**: Manchester, 80 bits (key1 64 + key2 16). Type 1/2: 300/600µs, prefix 0xAF3F/0xAF1C.
//! Type 3/4: 500µs, 45 preamble pairs, sync 1000+500 then 3×750µs; key1/key2 not inverted.
//! Button names match reference (vag_button_name): Unlock/Lock/Boot.
use super::{ProtocolDecoder, ProtocolTiming, DecodedSignal};
use super::aut64;
@@ -29,16 +32,18 @@ const TE_SHORT_12: u32 = 300;
const TE_LONG_12: u32 = 600;
const TE_DELTA_12: u32 = 80; // Preamble1/Data1 (ref vag.c 79/80)
// Reference-aligned deltas (vag.c)
const REF_RESET_DELTA: u32 = 79; // Reset: (300-duration)<=79, 500±79
const REF_PREAMBLE_SYNC: u32 = 80; // Preamble2/Sync2: 500±80, 1000±80, 750±80
const REF_SYNC2C_DELTA: u32 = 79; // Sync2C: diff<=79
// Reference-aligned deltas (vag.c VAG_NEAR / VAG_TOL_300 79, VAG_TOL_500 120)
const REF_RESET_DELTA: u32 = 79; // Reset: 300±79, 500±79 for Preamble2
const REF_PREAMBLE_SYNC: u32 = 80; // Preamble2 counting: 500±80
const REF_SYNC2_AB_DELTA: u32 = 79; // Sync2A/Sync2B: 500/1000/750±79 (ref VAG_NEAR(..., 79))
const REF_SYNC2C_DELTA: u32 = 79; // Sync2C: 750±79
const REF_GAP1_DELTA: u32 = 79; // Preamble1→Data1 gap 600µs ±79 (ref check_gap1)
// TEA constants
const TEA_DELTA: u32 = 0x9E3779B9;
const TEA_ROUNDS: usize = 32;
/// TEA key schedule for VAG (matches vag.c vag_tea_key_schedule)
/// TEA key schedule for VAG (vag.c vag_tea_key_schedule; VAG_TEA_DELTA 0x9E3779B9, 32 rounds)
static TEA_KEY_SCHEDULE: [u32; 4] = [0x0B46502D, 0x5E253718, 0x2BF93A19, 0x622C1206];
/// Manchester states
@@ -218,17 +223,17 @@ impl VagDecoder {
}
}
/// Check if dispatch byte matches Type 1/2
/// Type 1/2 dispatch check (vag.c vag_dispatch_type_1_2)
fn dispatch_type_1_2(dispatch: u8) -> bool {
dispatch == 0x2A || dispatch == 0x1C || dispatch == 0x46
}
/// Check if dispatch byte matches Type 3/4
/// Type 3/4 dispatch check (vag.c vag_dispatch_type_3_4)
fn dispatch_type_3_4(dispatch: u8) -> bool {
dispatch == 0x2B || dispatch == 0x1D || dispatch == 0x47
}
/// Validate decrypted button byte
/// Validate decrypted block button (vag.c vag_button_valid)
fn button_valid(dec: &[u8]) -> bool {
let dec_byte = dec[7];
let dec_btn = (dec_byte >> 4) & 0xF;
@@ -241,7 +246,7 @@ impl VagDecoder {
false
}
/// Check if decrypted button matches dispatch byte
/// Decrypted button vs dispatch (vag.c vag_button_matches)
fn button_matches(dec: &[u8], dispatch_byte: u8) -> bool {
let expected_btn = (dispatch_byte >> 4) & 0xF;
let dec_btn = (dec[7] >> 4) & 0xF;
@@ -254,7 +259,7 @@ impl VagDecoder {
false
}
/// Fill decoded fields from decrypted block
/// Fill decoded fields from decrypted block (vag.c vag_fill_from_decrypted)
fn fill_from_decrypted(&mut self, dec: &[u8], dispatch_byte: u8) {
let serial_raw = (dec[0] as u32)
| ((dec[1] as u32) << 8)
@@ -282,7 +287,7 @@ impl VagDecoder {
}
}
/// Parse key1/key2 and decrypt by type (AUT64/TEA, dispatch); matches vag.c vag_parse_data
/// Parse key1/key2 and decrypt by type (vag.c vag_parse_data)
fn parse_data(&mut self) {
self.decrypted = false;
self.serial = 0;
@@ -435,13 +440,13 @@ impl VagDecoder {
}
}
/// Get button name
/// Get button name (matches vag.c vag_button_name: Unlock/Lock/Boot)
#[allow(dead_code)]
fn get_button_name(btn: u8) -> &'static str {
match btn {
1 => "Unlock",
2 => "Lock",
4 => "Trunk",
1 | 0x10 => "Unlock",
2 | 0x20 => "Lock",
4 | 0x40 => "Boot",
_ => "Unknown",
}
}
@@ -692,7 +697,7 @@ impl VagDecoder {
Some(upload)
}
/// Get dispatch byte from button and type
/// Dispatch byte from button and type (vag.c vag_get_dispatch_byte)
fn get_dispatch_byte(btn: u8, vag_type: u8) -> u8 {
if vag_type == 1 || vag_type == 2 {
match btn {
@@ -711,7 +716,7 @@ impl VagDecoder {
}
}
/// Convert button code to byte for encoding
/// Convert button code to byte for encoding (matches vag.c vag_btn_to_byte)
fn btn_to_byte(btn: u8, vag_type: u8) -> u8 {
if vag_type == 1 {
btn
@@ -720,7 +725,7 @@ impl VagDecoder {
1 => 0x10,
2 => 0x20,
4 => 0x40,
_ => 0x20,
_ => btn, // ref default: return btn
}
}
}
@@ -885,20 +890,20 @@ impl ProtocolDecoder for VagDecoder {
return None;
}
// Check for gap (end of preamble)
// Check for gap (end of preamble): 600µs ±79, te_last 300±79 (ref check_gap1)
if self.header_count >= 201 {
let gap_diff = if duration > TE_LONG_12 {
duration - TE_LONG_12
} else {
TE_LONG_12 - duration
};
if gap_diff <= TE_DELTA_12 {
if gap_diff <= REF_GAP1_DELTA {
let prev_diff = if self.te_last > TE_SHORT_12 {
self.te_last - TE_SHORT_12
} else {
TE_SHORT_12 - self.te_last
};
if prev_diff <= TE_DELTA_12 {
if prev_diff <= REF_RESET_DELTA {
self.step = DecoderStep::Data1;
return None;
}
@@ -1037,20 +1042,20 @@ impl ProtocolDecoder for VagDecoder {
}
DecoderStep::Sync2A => {
// Matches vag.c: LOW 500±80 and te_last 1000±80 -> Sync2B
// Matches vag.c: LOW 500±79 and te_last 1000±79 -> Sync2B (VAG_NEAR(..., 79))
if !level {
let diff = if duration < TE_SHORT {
TE_SHORT - duration
} else {
duration - TE_SHORT
};
if diff < REF_PREAMBLE_SYNC {
if diff <= REF_SYNC2_AB_DELTA {
let prev_diff = if self.te_last < TE_LONG {
TE_LONG - self.te_last
} else {
self.te_last - TE_LONG
};
if prev_diff < REF_PREAMBLE_SYNC {
if prev_diff <= REF_SYNC2_AB_DELTA {
self.te_last = duration;
self.step = DecoderStep::Sync2B;
return None;
@@ -1061,14 +1066,14 @@ impl ProtocolDecoder for VagDecoder {
}
DecoderStep::Sync2B => {
// Matches vag.c: HIGH 750±80 -> Sync2C
// Matches vag.c: HIGH 750±79 -> Sync2C (VAG_NEAR(duration, 750, 79))
if level {
let diff = if duration < 750 {
750 - duration
} else {
duration - 750
};
if diff < REF_PREAMBLE_SYNC {
if diff <= REF_SYNC2_AB_DELTA {
self.te_last = duration;
self.step = DecoderStep::Sync2C;
return None;