From 2d7bdee30b93e3669850b9c16eed23174cf07b65 Mon Sep 17 00:00:00 2001 From: merlokk Date: Mon, 12 Feb 2018 18:53:12 +0200 Subject: [PATCH] added parity check of deciphered command --- client/cmdhf.c | 2 +- client/cmdhflist.c | 86 +++++++++++++++++++++++++++++++++------------- client/cmdhflist.h | 5 +-- 3 files changed, 67 insertions(+), 26 deletions(-) diff --git a/client/cmdhf.c b/client/cmdhf.c index 06382abb..ffbc4515 100644 --- a/client/cmdhf.c +++ b/client/cmdhf.c @@ -433,7 +433,7 @@ uint16_t printTraceLine(uint16_t tracepos, uint16_t traceLen, uint8_t *trace, ui } } - if (DecodeMifareData(frame, data_len, isResponse, mfData, &mfDataLen)) { + if (DecodeMifareData(frame, data_len, parityBytes, isResponse, mfData, &mfDataLen)) { memset(explanation, 0x00, sizeof(explanation)); if (!isResponse) { explanation[0] = '>'; diff --git a/client/cmdhflist.c b/client/cmdhflist.c index 7b3fdca5..a9691aa3 100644 --- a/client/cmdhflist.c +++ b/client/cmdhflist.c @@ -89,7 +89,6 @@ void annotateIso14443a(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) { case ISO14443A_CMD_WUPA: snprintf(exp,size,"WUPA"); - MifareAuthState = masNone; break; case ISO14443A_CMD_ANTICOLL_OR_SELECT:{ // 93 20 = Anticollision (usage: 9320 - answer: 4bytes UID+1byte UID-bytes-xor) @@ -115,7 +114,6 @@ void annotateIso14443a(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) } case ISO14443A_CMD_REQA: snprintf(exp,size,"REQA"); - MifareAuthState = masNone; break; case ISO14443A_CMD_READBLOCK: snprintf(exp,size,"READBLOCK(%d)",cmd[1]); break; case ISO14443A_CMD_WRITEBLOCK: snprintf(exp,size,"WRITEBLOCK(%d)",cmd[1]); break; @@ -189,6 +187,17 @@ void annotateIso14443a(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) } void annotateMifare(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize, uint8_t* parity, uint8_t paritysize, bool isResponse) { + if (!isResponse && cmdsize == 1) { + switch(cmd[0]) { + case ISO14443A_CMD_WUPA: + case ISO14443A_CMD_REQA: + MifareAuthState = masNone; + break; + default: + break; + } + } + // get UID if (MifareAuthState == masNone) { if (cmdsize == 9 && cmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT && cmd[1] == 0x70) { @@ -248,7 +257,7 @@ void annotateMifare(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize, uint8 } -bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, bool isResponse, uint8_t *mfData, size_t *mfDataLen) { +bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, uint8_t *parity, bool isResponse, uint8_t *mfData, size_t *mfDataLen) { static struct Crypto1State *traceCrypto1; static uint64_t mfLastKey; @@ -281,7 +290,8 @@ bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, bool isResponse, uint8_t *m crypto1_destroy(revstate); mfLastKey = lfsr; PrintAndLog(" | * | key | probable key:%x%x Prng:%s ks2:%08x ks3:%08x | |", - (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), (unsigned int)(lfsr & 0xFFFFFFFF), + (unsigned int)((lfsr & 0xFFFFFFFF00000000) >> 32), + (unsigned int)(lfsr & 0xFFFFFFFF), validate_prng_nonce(AuthData.nt) ? "WEAK": "HARD", AuthData.ks2, AuthData.ks3); @@ -290,19 +300,29 @@ bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, bool isResponse, uint8_t *m traceCrypto1 = lfsr_recovery64(AuthData.ks2, AuthData.ks3); } else { - printf("uid:%x nt:%x ar_enc:%x at_enc:%x\n", AuthData.uid, AuthData.nt, AuthData.ar_enc, AuthData.at_enc); - // check last used key if (mfLastKey) { - if (NestedCheckKey(mfLastKey, &AuthData, cmd, cmdsize)) { - traceCrypto1 = lfsr_recovery64(AuthData.ks2, AuthData.ks3); + if (NestedCheckKey(mfLastKey, &AuthData, cmd, cmdsize, parity)) { + PrintAndLog(" | * | key | last used key:%x%x ks2:%08x ks3:%08x | |", + (unsigned int)((mfLastKey & 0xFFFFFFFF00000000) >> 32), + (unsigned int)(mfLastKey & 0xFFFFFFFF), + AuthData.ks2, + AuthData.ks3); + + traceCrypto1 = lfsr_recovery64(AuthData.ks2, AuthData.ks3); }; } // check default keys if (!traceCrypto1) { for (int defaultKeyCounter = 0; defaultKeyCounter < MifareDefaultKeysSize; defaultKeyCounter++){ - if (NestedCheckKey(MifareDefaultKeys[defaultKeyCounter], &AuthData, cmd, cmdsize)) { + if (NestedCheckKey(MifareDefaultKeys[defaultKeyCounter], &AuthData, cmd, cmdsize, parity)) { + PrintAndLog(" | * | key | default key:%x%x ks2:%08x ks3:%08x | |", + (unsigned int)((MifareDefaultKeys[defaultKeyCounter] & 0xFFFFFFFF00000000) >> 32), + (unsigned int)(MifareDefaultKeys[defaultKeyCounter] & 0xFFFFFFFF), + AuthData.ks2, + AuthData.ks3); + traceCrypto1 = lfsr_recovery64(AuthData.ks2, AuthData.ks3); break; }; @@ -311,6 +331,7 @@ bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, bool isResponse, uint8_t *m // nested if (!traceCrypto1 && validate_prng_nonce(AuthData.nt)) { +printf("nested. uid:%x nt:%x ar_enc:%x at_enc:%x\n", AuthData.uid, AuthData.nt, AuthData.ar_enc, AuthData.at_enc); uint32_t ntx = prng_successor(AuthData.nt, 90); for (int i = 0; i < 16383; i++) { ntx = prng_successor(ntx, 1); @@ -339,6 +360,7 @@ bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, bool isResponse, uint8_t *m //hardnested if (!traceCrypto1) { + printf("hardnested not implemented. uid:%x nt:%x ar_enc:%x at_enc:%x\n", AuthData.uid, AuthData.nt, AuthData.ar_enc, AuthData.at_enc); } } @@ -384,37 +406,55 @@ bool NTParityChk(TAuthData *ad, uint32_t ntx) { return true; } -bool NestedCheckKey(uint64_t key, TAuthData *ad, uint8_t *cmd, uint8_t cmdsize) { +bool NestedCheckKey(uint64_t key, TAuthData *ad, uint8_t *cmd, uint8_t cmdsize, uint8_t *parity) { uint8_t buf[32] = {0}; struct Crypto1State *pcs; + AuthData.ks2 = 0; + AuthData.ks3 = 0; + pcs = crypto1_create(key); uint32_t nt1 = crypto1_word(pcs, ad->nt_enc ^ ad->uid, 1) ^ ad->nt_enc; uint32_t ar = prng_successor(nt1, 64); uint32_t at = prng_successor(nt1, 96); - printf("key> nested auth uid: %08x nt: %08x nt_parity: %s ar: %08x at: %08x\n", ad->uid, nt1, printBitsPar(&ad->nt_enc_par, 4), ar, at); - uint32_t nr1 = crypto1_word(pcs, ad->nr_enc, 1) ^ ad->nr_enc; + + crypto1_word(pcs, ad->nr_enc, 1); +// uint32_t nr1 = crypto1_word(pcs, ad->nr_enc, 1) ^ ad->nr_enc; // if needs deciphered nr uint32_t ar1 = crypto1_word(pcs, 0, 0) ^ ad->ar_enc; uint32_t at1 = crypto1_word(pcs, 0, 0) ^ ad->at_enc; - printf("key> the same key test. nr1: %08x ar1: %08x at1: %08x \n", nr1, ar1, at1); - if (NTParityChk(ad, nt1)) - printf("key> the same key test OK. key=%x%x\n", (unsigned int)((key & 0xFFFFFFFF00000000) >> 32), (unsigned int)(key & 0xFFFFFFFF)); - else { - printf("key> the same key test. check nt parity error.\n"); + if (!(ar == ar1 && at == at1 && NTParityChk(ad, nt1))) return false; - } memcpy(buf, cmd, cmdsize); mf_crypto1_decrypt(pcs, buf, cmdsize, 0); crypto1_destroy(pcs); - if(CheckCrc14443(CRC_14443_A, buf, cmdsize)) { - AuthData.ks2 = AuthData.ar_enc ^ ar; - AuthData.ks3 = AuthData.at_enc ^ at; - return true; - } else { + if(!CheckCrc14443(CRC_14443_A, buf, cmdsize)) + return false; + + if (!CheckCrypto1Parity(cmd, cmdsize, buf, parity)) return false; + + AuthData.ks2 = AuthData.ar_enc ^ ar; + AuthData.ks3 = AuthData.at_enc ^ at; + + return true; +} + +bool CheckCrypto1Parity(uint8_t *cmd, uint8_t cmdsize, uint8_t *cmd_enc, uint8_t *parity_enc) { + printf("parity check. size=%d\n", cmdsize); + printf("cmd =%s\n", sprint_hex(cmd, cmdsize)); + printf("cmd_enc=%s\n", sprint_hex(cmd_enc, cmdsize)); + printf("parity=%s\n", printBitsPar(parity_enc, cmdsize)); +// (oddparity8(ntx >> 8 & 0xff) ^ (ntx & 0x01) ^ ((ad->nt_enc_par >> 5) & 0x01) ^ (ad->nt_enc & 0x01)) || + for (int i = 0; i < cmdsize - 1; i++) { + bool b = oddparity8(cmd[i]) ^ (cmd[i + 1] & 0x01) ^ ((parity_enc[i / 8] >> (6 - i % 8)) & 0x01) ^ (cmd_enc[i + 1] & 0x01); + printf("i=%d b=%d\n", i, b); + if (b) + return false; } + + return true; } diff --git a/client/cmdhflist.h b/client/cmdhflist.h index 76b57392..977be288 100644 --- a/client/cmdhflist.h +++ b/client/cmdhflist.h @@ -34,8 +34,9 @@ extern uint8_t iso14443A_CRC_check(bool isResponse, uint8_t* data, uint8_t len); extern uint8_t mifare_CRC_check(bool isResponse, uint8_t* data, uint8_t len); extern void annotateIso14443a(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize); extern void annotateMifare(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize, uint8_t* parity, uint8_t paritysize, bool isResponse); -extern bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, bool isResponse, uint8_t *mfData, size_t *mfDataLen); +extern bool DecodeMifareData(uint8_t *cmd, uint8_t cmdsize, uint8_t *parity, bool isResponse, uint8_t *mfData, size_t *mfDataLen); extern bool NTParityChk(TAuthData *ad, uint32_t ntx); -extern bool NestedCheckKey(uint64_t key, TAuthData *ad, uint8_t *cmd, uint8_t cmdsize); +extern bool NestedCheckKey(uint64_t key, TAuthData *ad, uint8_t *cmd, uint8_t cmdsize, uint8_t *parity); +extern bool CheckCrypto1Parity(uint8_t *cmd, uint8_t cmdsize, uint8_t *cmd_enc, uint8_t *parity_enc); #endif // CMDHFLIST -- 2.39.2