added parity check of deciphered command
authormerlokk <olegmsn@gmail.com>
Mon, 12 Feb 2018 16:53:12 +0000 (18:53 +0200)
committermerlokk <olegmsn@gmail.com>
Mon, 12 Feb 2018 16:53:12 +0000 (18:53 +0200)
client/cmdhf.c
client/cmdhflist.c
client/cmdhflist.h

index 06382abbbd159ad83c4232eeeef4f1161c3da8a0..ffbc451580ca6ce045d53a9b2fe83d3477f00c7d 100644 (file)
@@ -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] = '>';
index 7b3fdca505a2427f4c4d06fec0adf99b4c6451bf..a9691aa30e3683bd55e3e35c265efac8f49f752e 100644 (file)
@@ -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;
 }
index 76b57392259e2ade054ad91ab277c1b1ea08d851..977be288925b1afe6e18ecdcacd7f0107768d6c0 100644 (file)
@@ -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
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