EM 4x05 login bf

This commit is contained in:
Philippe Teuwen 2020-10-20 13:18:43 +02:00
parent 9003b96312
commit 3b83e8e703
7 changed files with 110 additions and 8 deletions

View file

@ -978,6 +978,15 @@ static void PacketReceived(PacketCommandNG *packet) {
EM4xLogin(payload->password);
break;
}
case CMD_LF_EM4X_BF: {
struct p {
uint32_t start_pwd;
uint32_t n;
} PACKED;
struct p *payload = (struct p *) packet->data.asBytes;
EM4xBruteforce(payload->start_pwd, payload->n);
break;
}
case CMD_LF_EM4X_READWORD: {
struct p {
uint32_t password;

View file

@ -2467,7 +2467,7 @@ static uint8_t Prepare_Data(uint16_t data_low, uint16_t data_hi) {
// Requires: forwarLink_data filled with valid bits (1 bit per byte)
// fwd_bit_count set with number of bits to be sent
//====================================================================
static void SendForward(uint8_t fwd_bit_count) {
static void SendForward(uint8_t fwd_bit_count, bool fast) {
// iceman, 21.3us increments for the USclock verification.
// 55FC * 8us == 440us / 21.3 === 20.65 steps. could be too short. Go for 56FC instead
@ -2480,9 +2480,10 @@ static void SendForward(uint8_t fwd_bit_count) {
fwd_write_ptr = forwardLink_data;
fwd_bit_sz = fwd_bit_count;
if (! fast) {
// Set up FPGA, 125kHz or 95 divisor
LFSetupFPGAForADC(LF_DIVISOR_125, true);
}
// force 1st mod pulse (start gap must be longer for 4305)
fwd_bit_sz--; //prepare next bit modulation
fwd_write_ptr++;
@ -2505,13 +2506,59 @@ static void EM4xLoginEx(uint32_t pwd) {
forward_ptr = forwardLink_data;
uint8_t len = Prepare_Cmd(FWD_CMD_LOGIN);
len += Prepare_Data(pwd & 0xFFFF, pwd >> 16);
SendForward(len);
SendForward(len, false);
//WaitUS(20); // no wait for login command.
// should receive
// 0000 1010 ok
// 0000 0001 fail
}
void EM4xBruteforce(uint32_t start_pwd, uint32_t n) {
// With current timing, 18.6 ms per test = 53.8 pwds/s
reply_ng(CMD_LF_EM4X_BF, PM3_SUCCESS, NULL, 0);
StartTicks();
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
WaitMS(20);
LED_A_ON();
LFSetupFPGAForADC(LF_DIVISOR_125, true);
uint32_t candidates_found = 0;
for (uint32_t pwd = start_pwd; pwd < 0xFFFFFFFF; pwd++) {
if (((pwd - start_pwd) & 0x3F) == 0x00) {
WDT_HIT();
if (BUTTON_PRESS() || data_available()) {
Dbprintf("EM4x05 Bruteforce Interrupted");
break;
}
}
// Report progress every 256 attempts
if (((pwd - start_pwd) & 0xFF) == 0x00) {
Dbprintf("Trying: %06Xxx", pwd >> 8);
}
clear_trace();
forward_ptr = forwardLink_data;
uint8_t len = Prepare_Cmd(FWD_CMD_LOGIN);
len += Prepare_Data(pwd & 0xFFFF, pwd >> 16);
SendForward(len, true);
WaitUS(400);
DoPartialAcquisition(0, false, 350, 1000);
uint8_t *mem = BigBuf_get_addr();
if (mem[334] < 128) {
Dbprintf("Password candidate: " _GREEN_("%08X"), pwd);
if ((n != 0) && (candidates_found == n)) {
Dbprintf("EM4x05 Bruteforce Stopped. %i candidates found", candidates_found);
break;
}
}
// Beware: if smaller, tag might not have time to be back in listening state yet
WaitMS(1);
}
StopTicks();
FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
LEDsoff();
}
void EM4xLogin(uint32_t pwd) {
StartTicks();
@ -2558,7 +2605,7 @@ void EM4xReadWord(uint8_t addr, uint32_t pwd, uint8_t usepwd) {
uint8_t len = Prepare_Cmd(FWD_CMD_READ);
len += Prepare_Addr(addr);
SendForward(len);
SendForward(len, false);
WaitUS(400);
@ -2594,7 +2641,7 @@ void EM4xWriteWord(uint8_t addr, uint32_t data, uint32_t pwd, uint8_t usepwd) {
len += Prepare_Addr(addr);
len += Prepare_Data(data & 0xFFFF, data >> 16);
SendForward(len);
SendForward(len, false);
if (tearoff_hook() == PM3_ETEAROFF) { // tearoff occured
StopTicks();
@ -2636,7 +2683,7 @@ void EM4xProtectWord(uint32_t data, uint32_t pwd, uint8_t usepwd) {
uint8_t len = Prepare_Cmd(FWD_CMD_PROTECT);
len += Prepare_Data(data & 0xFFFF, data >> 16);
SendForward(len);
SendForward(len, false);
if (tearoff_hook() == PM3_ETEAROFF) { // tearoff occured
StopTicks();

View file

@ -57,6 +57,7 @@ void T55xxDangerousRawTest(uint8_t *data);
void TurnReadLFOn(uint32_t delay);
void EM4xLogin(uint32_t pwd);
void EM4xBruteforce(uint32_t start_pwd, uint32_t n);
void EM4xReadWord(uint8_t addr, uint32_t pwd, uint8_t usepwd);
void EM4xWriteWord(uint8_t addr, uint32_t data, uint32_t pwd, uint8_t usepwd);
void EM4xProtectWord(uint32_t data, uint32_t pwd, uint8_t usepwd);

View file

@ -647,6 +647,7 @@ static command_t CommandTable[] = {
{"4x05_write", CmdEM4x05Write, IfPm3Lf, "write word data to EM4x05/EM4x69"},
{"4x05_unlock", CmdEM4x05Unlock, IfPm3Lf, "execute tear off against EM4x05/EM4x69"},
{"4x05_sniff", CmdEM4x05Sniff, IfPm3Lf, "Attempt to recover em4x05 commands from sample buffer"},
{"4x05_brute", CmdEM4x05Brute, IfPm3Lf, "Bruteforce password"},
{"----------", CmdHelp, AlwaysAvailable, "----------------------- " _CYAN_("EM 4x50") " -----------------------"},
{"4x50_dump", CmdEM4x50Dump, IfPm3EM4x50, "dump EM4x50 tag"},
{"4x50_info", CmdEM4x50Info, IfPm3EM4x50, "tag information EM4x50"},

View file

@ -1178,6 +1178,48 @@ int CmdEM4x05Chk(const char *Cmd) {
return PM3_SUCCESS;
}
int CmdEM4x05Brute(const char *Cmd) {
CLIParserContext *ctx;
CLIParserInit(&ctx, "lf em 4x05_brute",
"This command tries to bruteforce the password of a EM4205/4305/4469/4569\n",
"Note: if you get many false positives, change position on the antenna"
"lf em 4x05_brute\n"
"lf em 4x05_brute -n 1 -> stop after first candidate found\n"
"lf em 4x05_brute -s 0x00000022B8 -> remember to use 0x for hex"
);
void *argtable[] = {
arg_param_begin,
arg_u64_0("s", "start", "<pwd>", "Start bruteforce enumeration from this password value"),
arg_int0("n", "", "<digits>", "Stop after having found n candidates. Default: 0 => infinite"),
arg_param_end
};
CLIExecWithReturn(ctx, Cmd, argtable, true);
uint32_t start_pwd = arg_get_u64_def(ctx, 1, 0);
uint32_t n = arg_get_int_def(ctx, 1, 0);
CLIParserFree(ctx);
PrintAndLogEx(NORMAL, "");
struct {
uint32_t start_pwd;
uint32_t n;
} PACKED payload;
payload.start_pwd = start_pwd;
payload.n = n;
clearCommandBuffer();
SendCommandNG(CMD_LF_EM4X_BF, (uint8_t *)&payload, sizeof(payload));
PacketResponseNG resp;
if (!WaitForResponseTimeout(CMD_LF_EM4X_BF, &resp, 1000)) {
PrintAndLogEx(WARNING, "(EM4x05 Bruteforce) timeout while waiting for reply.");
return PM3_ETIMEOUT;
}
PrintAndLogEx(INFO, "Bruteforce is running on device side, press button to interrupt");
return PM3_SUCCESS;
}
typedef struct {
uint16_t cnt;
uint32_t value;

View file

@ -28,5 +28,6 @@ int CmdEM4x05Info(const char *Cmd);
int CmdEM4x05Chk(const char *Cmd);
int CmdEM4x05Unlock(const char *Cmd);
int CmdEM4x05Sniff(const char *Cmd);
int CmdEM4x05Brute(const char *Cmd);
#endif

View file

@ -500,6 +500,7 @@ typedef struct {
#define CMD_LF_EM4X_READWORD 0x0218
#define CMD_LF_EM4X_WRITEWORD 0x0219
#define CMD_LF_EM4X_PROTECTWORD 0x021B
#define CMD_LF_EM4X_BF 0x022A
#define CMD_LF_IO_WATCH 0x021A
#define CMD_LF_EM410X_WATCH 0x021C
#define CMD_LF_EM4X50_INFO 0x0240