mirror of
https://github.com/DarkFlippers/unleashed-firmware
synced 2024-11-23 04:53:08 +00:00
Identified method to reduce candidate states
This commit is contained in:
parent
213ec1dfb0
commit
9ba78bf085
1 changed files with 101 additions and 88 deletions
|
@ -838,37 +838,15 @@ NfcCommand mf_classic_poller_handler_key_reuse_read_sector(MfClassicPoller* inst
|
|||
return command;
|
||||
}
|
||||
|
||||
void nonce_distance(uint32_t* msb, uint32_t* lsb) {
|
||||
uint16_t x = 1, pos;
|
||||
uint8_t calc_ok = 0;
|
||||
|
||||
for(uint16_t i = 1; i; ++i) {
|
||||
pos = (x & 0xff) << 8 | x >> 8;
|
||||
|
||||
if((pos == *msb) & !(calc_ok >> 0 & 0x01)) {
|
||||
*msb = i;
|
||||
calc_ok |= 0x01;
|
||||
}
|
||||
|
||||
if((pos == *lsb) & !(calc_ok >> 1 & 0x01)) {
|
||||
*lsb = i;
|
||||
calc_ok |= 0x02;
|
||||
}
|
||||
|
||||
if(calc_ok == 0x03) {
|
||||
return;
|
||||
}
|
||||
|
||||
bool validate_prng_nonce(uint32_t nonce) {
|
||||
if(nonce == 0) return false;
|
||||
uint16_t x = nonce >> 16;
|
||||
x = (x & 0xff) << 8 | x >> 8;
|
||||
for(uint8_t i = 0; i < 16; i++) {
|
||||
x = x >> 1 | (x ^ x >> 2 ^ x >> 3 ^ x >> 5) << 15;
|
||||
}
|
||||
}
|
||||
|
||||
// TODO: Faster? https://github.com/RfidResearchGroup/proxmark3/commit/bd3e8db852186d4ab9d5dda890d1cd52389b1254
|
||||
bool validate_prng_nonce(uint32_t nonce) {
|
||||
uint32_t msb = nonce >> 16;
|
||||
uint32_t lsb = nonce & 0xffff;
|
||||
nonce_distance(&msb, &lsb);
|
||||
return ((65535 - msb + lsb) % 65535) == 16;
|
||||
x = (x & 0xff) << 8 | x >> 8;
|
||||
return x == (nonce & 0xFFFF);
|
||||
}
|
||||
|
||||
// Return 1 if the nonce is invalid else return 0
|
||||
|
@ -883,9 +861,17 @@ uint8_t valid_nonce(uint32_t Nt, uint32_t NtEnc, uint32_t Ks1, uint8_t *parity)
|
|||
*/
|
||||
|
||||
// Helper function to add a nonce to the array
|
||||
static bool add_nested_nonce(MfClassicNestedNonceArray* array, uint32_t cuid, uint8_t key_idx, uint32_t nt, uint32_t nt_enc, uint8_t par, uint16_t dist) {
|
||||
MfClassicNestedNonce* new_nonces = realloc(array->nonces, (array->count + 1) * sizeof(MfClassicNestedNonce));
|
||||
if (new_nonces == NULL) return false;
|
||||
static bool add_nested_nonce(
|
||||
MfClassicNestedNonceArray* array,
|
||||
uint32_t cuid,
|
||||
uint8_t key_idx,
|
||||
uint32_t nt,
|
||||
uint32_t nt_enc,
|
||||
uint8_t par,
|
||||
uint16_t dist) {
|
||||
MfClassicNestedNonce* new_nonces =
|
||||
realloc(array->nonces, (array->count + 1) * sizeof(MfClassicNestedNonce));
|
||||
if(new_nonces == NULL) return false;
|
||||
|
||||
array->nonces = new_nonces;
|
||||
array->nonces[array->count].cuid = cuid;
|
||||
|
@ -905,11 +891,11 @@ NfcCommand mf_classic_poller_handler_nested_analyze_prng(MfClassicPoller* instan
|
|||
// Analyze PRNG by collecting nt
|
||||
uint8_t nonce_limit = 10;
|
||||
|
||||
if (dict_attack_ctx->nt_count > 0) {
|
||||
if(dict_attack_ctx->nt_count > 0) {
|
||||
if(!validate_prng_nonce(dict_attack_ctx->nt_prev)) dict_attack_ctx->hard_nt_count++;
|
||||
}
|
||||
|
||||
if(dict_attack_ctx->nt_count <= nonce_limit) {
|
||||
if(dict_attack_ctx->nt_count < nonce_limit) {
|
||||
instance->state = MfClassicPollerStateNestedCollectNt;
|
||||
return command;
|
||||
}
|
||||
|
@ -933,6 +919,7 @@ NfcCommand mf_classic_poller_handler_nested_analyze_backdoor(MfClassicPoller* in
|
|||
MfClassicPollerDictAttackContext* dict_attack_ctx = &instance->mode_ctx.dict_attack_ctx;
|
||||
// TODO: Check for Fudan backdoor
|
||||
dict_attack_ctx->backdoor = MfClassicBackdoorNone;
|
||||
instance->state = MfClassicPollerStateNestedController;
|
||||
return command;
|
||||
}
|
||||
|
||||
|
@ -962,11 +949,7 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt(MfClassicPoller* instance
|
|||
|
||||
NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* instance) {
|
||||
// TODO: Collect parity
|
||||
// TODO: FURI_CRITICAL_ENTER
|
||||
// xTickCount
|
||||
// Modify targets/f7/furi_hal/furi_hal_rtc.c to expose sub-second time (https://stackoverflow.com/questions/55534873/how-to-setup-the-stm32f4-real-time-clockrtc-to-get-valid-values-in-the-sub-sec)
|
||||
// furi_hal_rtc_get_timestamp isn't precise enough
|
||||
// TODO: Measure ticks with https://github.com/flipperdevices/flipperzero-firmware/blob/bec6bd381f222cf14658fd862a2c7f6e620bbf00/targets/f7/furi_hal/furi_hal_idle_timer.h#L51
|
||||
// TODO: Use the mode (most frequently observed) value and parity to reliably get a single candidate state
|
||||
/*
|
||||
uint32_t ncount = 0;
|
||||
uint32_t nttest = prng_successor(nt1, dmin - 1);
|
||||
|
@ -986,16 +969,17 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* inst
|
|||
// TODO: Target sector, key A/B
|
||||
|
||||
do {
|
||||
if (dict_attack_ctx->prng_type == MfClassicPrngTypeHard) {
|
||||
if(dict_attack_ctx->prng_type == MfClassicPrngTypeHard) {
|
||||
FURI_LOG_E(TAG, "Hard PRNG, skipping calibration");
|
||||
// TODO: Collect hardnested nonces (cuid, sec, par, nt_enc, A/B)
|
||||
// https://github.com/AloneLiberty/FlipperNested/blob/eba6163d7ef22adef5f9fe4d77a78ccfcc27a952/lib/nested/nested.c#L564-L645
|
||||
break;
|
||||
}
|
||||
|
||||
uint8_t block = mf_classic_get_first_block_num_of_sector(dict_attack_ctx->reuse_key_sector);
|
||||
uint8_t block =
|
||||
mf_classic_get_first_block_num_of_sector(dict_attack_ctx->reuse_key_sector);
|
||||
uint32_t cuid = iso14443_3a_get_cuid(instance->data->iso14443_3a_data);
|
||||
|
||||
|
||||
MfClassicAuthContext auth_ctx = {};
|
||||
MfClassicError error;
|
||||
|
||||
|
@ -1005,7 +989,6 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* inst
|
|||
uint32_t nt_enc_prev = 0;
|
||||
uint32_t same_nt_enc_cnt = 0;
|
||||
bool static_encrypted = false;
|
||||
// Store last timestamp
|
||||
|
||||
// Step 1: Perform full authentication once
|
||||
error = mf_classic_poller_auth(
|
||||
|
@ -1015,7 +998,7 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* inst
|
|||
dict_attack_ctx->current_key_type,
|
||||
&auth_ctx);
|
||||
|
||||
if (error != MfClassicErrorNone) {
|
||||
if(error != MfClassicErrorNone) {
|
||||
FURI_LOG_E(TAG, "Failed to perform full authentication");
|
||||
break;
|
||||
}
|
||||
|
@ -1025,7 +1008,7 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* inst
|
|||
nt_prev = bit_lib_bytes_to_num_be(auth_ctx.nt.data, sizeof(MfClassicNt));
|
||||
|
||||
// Step 2: Perform nested authentication multiple times
|
||||
for (uint32_t round_no = 0; round_no < rounds; round_no++) {
|
||||
for(uint32_t round_no = 0; round_no < rounds; round_no++) {
|
||||
error = mf_classic_poller_auth_nested(
|
||||
instance,
|
||||
block,
|
||||
|
@ -1033,15 +1016,15 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* inst
|
|||
dict_attack_ctx->current_key_type,
|
||||
&auth_ctx);
|
||||
|
||||
if (error != MfClassicErrorNone) {
|
||||
if(error != MfClassicErrorNone) {
|
||||
FURI_LOG_E(TAG, "Failed to perform nested authentication %lu", round_no);
|
||||
continue;
|
||||
}
|
||||
|
||||
uint32_t nt_enc = bit_lib_bytes_to_num_be(auth_ctx.nt.data, sizeof(MfClassicNt));
|
||||
if (nt_enc == nt_enc_prev) {
|
||||
if(nt_enc == nt_enc_prev) {
|
||||
same_nt_enc_cnt++;
|
||||
if (same_nt_enc_cnt > 3) {
|
||||
if(same_nt_enc_cnt > 3) {
|
||||
static_encrypted = true;
|
||||
break;
|
||||
}
|
||||
|
@ -1052,15 +1035,22 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* inst
|
|||
nt_enc_arr[round_no] = nt_enc;
|
||||
}
|
||||
|
||||
if (static_encrypted) {
|
||||
if(static_encrypted) {
|
||||
FURI_LOG_E(TAG, "Static encrypted nonce detected");
|
||||
if (dict_attack_ctx->backdoor == MfClassicBackdoorFM11RF08S) {
|
||||
if(dict_attack_ctx->backdoor == MfClassicBackdoorFM11RF08S) {
|
||||
// TODO: Backdoor static nested attack
|
||||
break;
|
||||
} else {
|
||||
// TODO: If not present, just log nonces with parity bits
|
||||
bool success = add_nested_nonce(&result, cuid, dict_attack_ctx->reuse_key_sector, nt_prev, nt_enc_prev, 0, 65535);
|
||||
if (!success) {
|
||||
bool success = add_nested_nonce(
|
||||
&result,
|
||||
cuid,
|
||||
dict_attack_ctx->reuse_key_sector,
|
||||
nt_prev,
|
||||
nt_enc_prev,
|
||||
0,
|
||||
UINT16_MAX);
|
||||
if(!success) {
|
||||
FURI_LOG_E(TAG, "Failed to add nested nonce to array. OOM?");
|
||||
}
|
||||
break;
|
||||
|
@ -1069,44 +1059,57 @@ NfcCommand mf_classic_poller_handler_nested_collect_nt_enc(MfClassicPoller* inst
|
|||
|
||||
// Find the distance between each nonce
|
||||
// TODO: Distance calculation
|
||||
// TODO: Avoid repeated calibration
|
||||
FURI_LOG_E(TAG, "Calibrating distance between nonces");
|
||||
// Checking for d_min == 0 is more of a workaround for not having a proper calibration process
|
||||
if(dict_attack_ctx->d_min == 0) dict_attack_ctx->d_min = UINT16_MAX;
|
||||
uint64_t known_key = bit_lib_bytes_to_num_be(dict_attack_ctx->current_key.data, 6);
|
||||
Crypto1 crypto;
|
||||
crypto1_init(&crypto, known_key);
|
||||
// Skip the first round (typically an outlier)
|
||||
for (uint32_t rtr = 1; rtr < rounds; rtr++) {
|
||||
for(uint32_t rtr = 0; rtr < rounds; rtr++) {
|
||||
bool found = false;
|
||||
for (int i = 0; i < 65535; i++) {
|
||||
for(int i = 0; i < 65535; i++) {
|
||||
Crypto1 crypto_temp = {.odd = crypto.odd, .even = crypto.even};
|
||||
uint32_t nth_successor = prng_successor(nt_prev, i);
|
||||
if ((nth_successor ^ crypto1_word(&crypto_temp, cuid ^ nth_successor, 0)) == nt_enc_arr[rtr]) {
|
||||
if((nth_successor ^ crypto1_word(&crypto_temp, cuid ^ nth_successor, 0)) !=
|
||||
nt_enc_arr[rtr]) {
|
||||
continue;
|
||||
}
|
||||
if(rtr > 0) {
|
||||
FURI_LOG_E(TAG, "nt_enc (plain) %08lx", nth_successor);
|
||||
FURI_LOG_E(TAG, "dist from nt prev: %i", i);
|
||||
if (i > dict_attack_ctx->d_max) {
|
||||
if(i > dict_attack_ctx->d_max) {
|
||||
dict_attack_ctx->d_max = i;
|
||||
}
|
||||
if (i < dict_attack_ctx->d_min) {
|
||||
if(i < dict_attack_ctx->d_min) {
|
||||
dict_attack_ctx->d_min = i;
|
||||
}
|
||||
nt_prev = nth_successor;
|
||||
found = true;
|
||||
break;
|
||||
}
|
||||
nt_prev = nth_successor;
|
||||
found = true;
|
||||
break;
|
||||
}
|
||||
if (!found) {
|
||||
if(!found) {
|
||||
FURI_LOG_E(TAG, "Failed to find distance for nt_enc %08lx", nt_enc_arr[rtr]);
|
||||
FURI_LOG_E(TAG, "using key %06llx and uid %08lx, nt_prev is %08lx", known_key, cuid, nt_prev);
|
||||
FURI_LOG_E(
|
||||
TAG,
|
||||
"using key %06llx and uid %08lx, nt_prev is %08lx",
|
||||
known_key,
|
||||
cuid,
|
||||
nt_prev);
|
||||
}
|
||||
}
|
||||
bool is_static = (dict_attack_ctx->d_min == dict_attack_ctx->d_max);
|
||||
|
||||
FURI_LOG_E(
|
||||
TAG,
|
||||
"Calibration completed: min=%u max=%u static: %s",
|
||||
dict_attack_ctx->d_min,
|
||||
dict_attack_ctx->d_max,
|
||||
is_static ? "true" : "false");
|
||||
"Calibration completed: min=%u max=%u static: %s",
|
||||
dict_attack_ctx->d_min,
|
||||
dict_attack_ctx->d_max,
|
||||
is_static ? "true" : "false");
|
||||
|
||||
//printf("ks: %08x\n", nth_successor ^ nt_enc);
|
||||
//dict_attack_ctx->nested_target_key
|
||||
} while(false);
|
||||
|
||||
instance->state = MfClassicPollerStateNestedController;
|
||||
|
@ -1135,18 +1138,31 @@ NfcCommand mf_classic_poller_handler_nested_log(MfClassicPoller* instance) {
|
|||
FuriString* temp_str = furi_string_alloc();
|
||||
|
||||
do {
|
||||
if ((dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) && (dict_attack_ctx->nested_nonce.count != 2)) {
|
||||
FURI_LOG_E(TAG, "MfClassicPollerStateNestedLog expected 2 nonces, received %u", dict_attack_ctx->nested_nonce.count);
|
||||
if((dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) &&
|
||||
(dict_attack_ctx->nested_nonce.count != 2)) {
|
||||
FURI_LOG_E(
|
||||
TAG,
|
||||
"MfClassicPollerStateNestedLog expected 2 nonces, received %u",
|
||||
dict_attack_ctx->nested_nonce.count);
|
||||
break;
|
||||
}
|
||||
|
||||
if(!buffered_file_stream_open(stream, MF_CLASSIC_NESTED_LOGS_FILE_PATH, FSAM_WRITE, FSOM_OPEN_APPEND)) break;
|
||||
if(!buffered_file_stream_open(
|
||||
stream, MF_CLASSIC_NESTED_LOGS_FILE_PATH, FSAM_WRITE, FSOM_OPEN_APPEND))
|
||||
break;
|
||||
|
||||
bool params_write_success = true;
|
||||
for(size_t i = 0; i < dict_attack_ctx->nested_nonce.count; i++) {
|
||||
MfClassicNestedNonce* nonce = &dict_attack_ctx->nested_nonce.nonces[i];
|
||||
furi_string_printf(temp_str, "Sec %d key %c cuid %08lx", (nonce->key_idx / 2), (nonce->key_idx % 2 == 0) ? 'A' : 'B', nonce->cuid);
|
||||
for(uint8_t nt_idx = 0; nt_idx < ((dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) ? 2 : 1); nt_idx++) {
|
||||
furi_string_printf(
|
||||
temp_str,
|
||||
"Sec %d key %c cuid %08lx",
|
||||
(nonce->key_idx / 2),
|
||||
(nonce->key_idx % 2 == 0) ? 'A' : 'B',
|
||||
nonce->cuid);
|
||||
for(uint8_t nt_idx = 0;
|
||||
nt_idx < ((dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) ? 2 : 1);
|
||||
nt_idx++) {
|
||||
furi_string_cat_printf(
|
||||
temp_str,
|
||||
" nt%u %08lx ks%u %08lx par%u ",
|
||||
|
@ -1159,7 +1175,7 @@ NfcCommand mf_classic_poller_handler_nested_log(MfClassicPoller* instance) {
|
|||
furi_string_cat_printf(temp_str, "%u", (nonce->par >> (3 - pb)) & 1);
|
||||
}
|
||||
}
|
||||
if (dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) {
|
||||
if(dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) {
|
||||
furi_string_cat_printf(temp_str, " dist %u\n", nonce->dist);
|
||||
} else {
|
||||
furi_string_cat_printf(temp_str, "\n");
|
||||
|
@ -1189,21 +1205,21 @@ NfcCommand mf_classic_poller_handler_nested_controller(MfClassicPoller* instance
|
|||
// Iterate through keys
|
||||
NfcCommand command = NfcCommandContinue;
|
||||
MfClassicPollerDictAttackContext* dict_attack_ctx = &instance->mode_ctx.dict_attack_ctx;
|
||||
if (dict_attack_ctx->nested_nonce.count > 0) {
|
||||
if (dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) {
|
||||
if(dict_attack_ctx->nested_nonce.count > 0) {
|
||||
if(dict_attack_ctx->prng_type == MfClassicPrngTypeWeak) {
|
||||
instance->state = MfClassicPollerStateNestedDictAttack;
|
||||
return command;
|
||||
} else if (dict_attack_ctx->prng_type == MfClassicPrngTypeHard) {
|
||||
} else if(dict_attack_ctx->prng_type == MfClassicPrngTypeHard) {
|
||||
instance->state = MfClassicPollerStateNestedLog;
|
||||
return command;
|
||||
}
|
||||
}
|
||||
if (dict_attack_ctx->backdoor == MfClassicBackdoorUnknown) {
|
||||
if(dict_attack_ctx->backdoor == MfClassicBackdoorUnknown) {
|
||||
instance->state = MfClassicPollerStateNestedAnalyzeBackdoor;
|
||||
return command;
|
||||
}
|
||||
// Target all sectors, key A and B
|
||||
for (uint8_t key_idx = 0; key_idx <= (instance->sectors_total * 2); key_idx++) {
|
||||
for(uint8_t key_idx = 0; key_idx <= (instance->sectors_total * 2); key_idx++) {
|
||||
dict_attack_ctx->nested_target_key = key_idx;
|
||||
instance->state = MfClassicPollerStateNestedCollectNtEnc;
|
||||
return command;
|
||||
|
@ -1253,15 +1269,12 @@ static const MfClassicPollerReadHandler
|
|||
[MfClassicPollerStateKeyReuseAuthKeyB] = mf_classic_poller_handler_key_reuse_auth_key_b,
|
||||
[MfClassicPollerStateKeyReuseReadSector] = mf_classic_poller_handler_key_reuse_read_sector,
|
||||
[MfClassicPollerStateNestedAnalyzePRNG] = mf_classic_poller_handler_nested_analyze_prng,
|
||||
[MfClassicPollerStateNestedAnalyzeBackdoor] = mf_classic_poller_handler_nested_analyze_backdoor,
|
||||
[MfClassicPollerStateNestedCollectNt] =
|
||||
mf_classic_poller_handler_nested_collect_nt,
|
||||
[MfClassicPollerStateNestedController] =
|
||||
mf_classic_poller_handler_nested_controller,
|
||||
[MfClassicPollerStateNestedCollectNtEnc] =
|
||||
mf_classic_poller_handler_nested_collect_nt_enc,
|
||||
[MfClassicPollerStateNestedDictAttack] =
|
||||
mf_classic_poller_handler_nested_dict_attack,
|
||||
[MfClassicPollerStateNestedAnalyzeBackdoor] =
|
||||
mf_classic_poller_handler_nested_analyze_backdoor,
|
||||
[MfClassicPollerStateNestedCollectNt] = mf_classic_poller_handler_nested_collect_nt,
|
||||
[MfClassicPollerStateNestedController] = mf_classic_poller_handler_nested_controller,
|
||||
[MfClassicPollerStateNestedCollectNtEnc] = mf_classic_poller_handler_nested_collect_nt_enc,
|
||||
[MfClassicPollerStateNestedDictAttack] = mf_classic_poller_handler_nested_dict_attack,
|
||||
[MfClassicPollerStateNestedLog] = mf_classic_poller_handler_nested_log,
|
||||
[MfClassicPollerStateSuccess] = mf_classic_poller_handler_success,
|
||||
[MfClassicPollerStateFail] = mf_classic_poller_handler_fail,
|
||||
|
@ -1348,4 +1361,4 @@ const NfcPollerBase mf_classic_poller = {
|
|||
.run = (NfcPollerRun)mf_classic_poller_run,
|
||||
.detect = (NfcPollerDetect)mf_classic_poller_detect,
|
||||
.get_data = (NfcPollerGetData)mf_classic_poller_get_data,
|
||||
};
|
||||
};
|
||||
|
|
Loading…
Reference in a new issue