X-Git-Url: https://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/4f131b53ea7e9a66f5c7269fc35b11f8038cbf3e..refs/pull/580/head:/client/cmdhflist.c diff --git a/client/cmdhflist.c b/client/cmdhflist.c index 86562e4c..cf69abba 100644 --- a/client/cmdhflist.c +++ b/client/cmdhflist.c @@ -13,5 +13,593 @@ #include #include #include +#include +#include +#include "util.h" +#include "data.h" +#include "ui.h" +#include "iso14443crc.h" +#include "parity.h" +#include "protocols.h" +#include "crapto1/crapto1.h" +#include "mifarehost.h" +#include "mifaredefault.h" +enum MifareAuthSeq { + masNone, + masNt, + masNrAr, + masAt, + masAuthComplete, + masFirstData, + masData, + masError, +}; +static enum MifareAuthSeq MifareAuthState; +static TAuthData AuthData; + +void ClearAuthData() { + AuthData.uid = 0; + AuthData.nt = 0; + AuthData.first_auth = true; + AuthData.ks2 = 0; + AuthData.ks3 = 0; +} + +/** + * @brief iso14443A_CRC_check Checks CRC in command or response + * @param isResponse + * @param data + * @param len + * @return 0 : CRC-command, CRC not ok + * 1 : CRC-command, CRC ok + * 2 : Not crc-command + */ +uint8_t iso14443A_CRC_check(bool isResponse, uint8_t* data, uint8_t len) +{ + uint8_t b1,b2; + + if(len <= 2) return 2; + + if(isResponse & (len < 6)) return 2; + + ComputeCrc14443(CRC_14443_A, data, len-2, &b1, &b2); + if (b1 != data[len-2] || b2 != data[len-1]) { + return 0; + } else { + return 1; + } +} + +uint8_t mifare_CRC_check(bool isResponse, uint8_t* data, uint8_t len) +{ + switch(MifareAuthState) { + case masNone: + case masError: + return iso14443A_CRC_check(isResponse, data, len); + default: + return 2; + } +} + +void annotateIclass(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) +{ + switch(cmd[0]) + { + case ICLASS_CMD_ACTALL: snprintf(exp,size,"ACTALL"); break; + case ICLASS_CMD_READ_OR_IDENTIFY:{ + if(cmdsize > 1){ + snprintf(exp,size,"READ(%d)",cmd[1]); + }else{ + snprintf(exp,size,"IDENTIFY"); + } + break; + } + case ICLASS_CMD_SELECT: snprintf(exp,size,"SELECT"); break; + case ICLASS_CMD_PAGESEL: snprintf(exp,size,"PAGESEL(%d)", cmd[1]); break; + case ICLASS_CMD_READCHECK_KC:snprintf(exp,size,"READCHECK[Kc](%d)", cmd[1]); break; + case ICLASS_CMD_READCHECK_KD:snprintf(exp,size,"READCHECK[Kd](%d)", cmd[1]); break; + case ICLASS_CMD_CHECK: snprintf(exp,size,"CHECK"); break; + case ICLASS_CMD_DETECT: snprintf(exp,size,"DETECT"); break; + case ICLASS_CMD_HALT: snprintf(exp,size,"HALT"); break; + case ICLASS_CMD_UPDATE: snprintf(exp,size,"UPDATE(%d)",cmd[1]); break; + case ICLASS_CMD_ACT: snprintf(exp,size,"ACT"); break; + case ICLASS_CMD_READ4: snprintf(exp,size,"READ4(%d)",cmd[1]); break; + default: snprintf(exp,size,"?"); break; + } + return; +} + +void annotateIso15693(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) +{ + + if(cmd[0] == 0x26) + { + switch(cmd[1]){ + case ISO15693_INVENTORY :snprintf(exp, size, "INVENTORY");break; + case ISO15693_STAYQUIET :snprintf(exp, size, "STAY_QUIET");break; + default: snprintf(exp,size,"?"); break; + + } + }else if(cmd[0] == 0x02) + { + switch(cmd[1]) + { + case ISO15693_READBLOCK :snprintf(exp, size, "READBLOCK");break; + case ISO15693_WRITEBLOCK :snprintf(exp, size, "WRITEBLOCK");break; + case ISO15693_LOCKBLOCK :snprintf(exp, size, "LOCKBLOCK");break; + case ISO15693_READ_MULTI_BLOCK :snprintf(exp, size, "READ_MULTI_BLOCK");break; + case ISO15693_SELECT :snprintf(exp, size, "SELECT");break; + case ISO15693_RESET_TO_READY :snprintf(exp, size, "RESET_TO_READY");break; + case ISO15693_WRITE_AFI :snprintf(exp, size, "WRITE_AFI");break; + case ISO15693_LOCK_AFI :snprintf(exp, size, "LOCK_AFI");break; + case ISO15693_WRITE_DSFID :snprintf(exp, size, "WRITE_DSFID");break; + case ISO15693_LOCK_DSFID :snprintf(exp, size, "LOCK_DSFID");break; + case ISO15693_GET_SYSTEM_INFO :snprintf(exp, size, "GET_SYSTEM_INFO");break; + case ISO15693_READ_MULTI_SECSTATUS :snprintf(exp, size, "READ_MULTI_SECSTATUS");break; + default: snprintf(exp,size,"?"); break; + } + } +} + + +void annotateTopaz(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) +{ + switch(cmd[0]) { + case TOPAZ_REQA :snprintf(exp, size, "REQA");break; + case TOPAZ_WUPA :snprintf(exp, size, "WUPA");break; + case TOPAZ_RID :snprintf(exp, size, "RID");break; + case TOPAZ_RALL :snprintf(exp, size, "RALL");break; + case TOPAZ_READ :snprintf(exp, size, "READ");break; + case TOPAZ_WRITE_E :snprintf(exp, size, "WRITE-E");break; + case TOPAZ_WRITE_NE :snprintf(exp, size, "WRITE-NE");break; + case TOPAZ_RSEG :snprintf(exp, size, "RSEG");break; + case TOPAZ_READ8 :snprintf(exp, size, "READ8");break; + case TOPAZ_WRITE_E8 :snprintf(exp, size, "WRITE-E8");break; + case TOPAZ_WRITE_NE8 :snprintf(exp, size, "WRITE-NE8");break; + default: snprintf(exp,size,"?"); break; + } +} + + +/** +06 00 = INITIATE +0E xx = SELECT ID (xx = Chip-ID) +0B = Get UID +08 yy = Read Block (yy = block number) +09 yy dd dd dd dd = Write Block (yy = block number; dd dd dd dd = data to be written) +0C = Reset to Inventory +0F = Completion +0A 11 22 33 44 55 66 = Authenticate (11 22 33 44 55 66 = data to authenticate) +**/ + +void annotateIso14443b(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) +{ + switch(cmd[0]){ + case ISO14443B_REQB : snprintf(exp,size,"REQB");break; + case ISO14443B_ATTRIB : snprintf(exp,size,"ATTRIB");break; + case ISO14443B_HALT : snprintf(exp,size,"HALT");break; + case ISO14443B_INITIATE : snprintf(exp,size,"INITIATE");break; + case ISO14443B_SELECT : snprintf(exp,size,"SELECT(%d)",cmd[1]);break; + case ISO14443B_GET_UID : snprintf(exp,size,"GET UID");break; + case ISO14443B_READ_BLK : snprintf(exp,size,"READ_BLK(%d)", cmd[1]);break; + case ISO14443B_WRITE_BLK : snprintf(exp,size,"WRITE_BLK(%d)",cmd[1]);break; + case ISO14443B_RESET : snprintf(exp,size,"RESET");break; + case ISO14443B_COMPLETION : snprintf(exp,size,"COMPLETION");break; + case ISO14443B_AUTHENTICATE : snprintf(exp,size,"AUTHENTICATE");break; + default : snprintf(exp,size ,"?");break; + } + +} + +void annotateIso14443a(char *exp, size_t size, uint8_t* cmd, uint8_t cmdsize) +{ + switch(cmd[0]) + { + case ISO14443A_CMD_WUPA: + snprintf(exp,size,"WUPA"); + break; + case ISO14443A_CMD_ANTICOLL_OR_SELECT:{ + // 93 20 = Anticollision (usage: 9320 - answer: 4bytes UID+1byte UID-bytes-xor) + // 93 70 = Select (usage: 9370+5bytes 9320 answer - answer: 1byte SAK) + if(cmd[1] == 0x70) + { + snprintf(exp,size,"SELECT_UID"); break; + }else + { + snprintf(exp,size,"ANTICOLL"); break; + } + } + case ISO14443A_CMD_ANTICOLL_OR_SELECT_2:{ + //95 20 = Anticollision of cascade level2 + //95 70 = Select of cascade level2 + if(cmd[2] == 0x70) + { + snprintf(exp,size,"SELECT_UID-2"); break; + }else + { + snprintf(exp,size,"ANTICOLL-2"); break; + } + } + case ISO14443A_CMD_REQA: + snprintf(exp,size,"REQA"); + 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; + case ISO14443A_CMD_HALT: + snprintf(exp,size,"HALT"); + MifareAuthState = masNone; + break; + case ISO14443A_CMD_RATS: snprintf(exp,size,"RATS"); break; + case MIFARE_CMD_INC: snprintf(exp,size,"INC(%d)",cmd[1]); break; + case MIFARE_CMD_DEC: snprintf(exp,size,"DEC(%d)",cmd[1]); break; + case MIFARE_CMD_RESTORE: snprintf(exp,size,"RESTORE(%d)",cmd[1]); break; + case MIFARE_CMD_TRANSFER: snprintf(exp,size,"TRANSFER(%d)",cmd[1]); break; + case MIFARE_AUTH_KEYA: + if ( cmdsize > 3) { + snprintf(exp,size,"AUTH-A(%d)",cmd[1]); + MifareAuthState = masNt; + } else { + // case MIFARE_ULEV1_VERSION : both 0x60. + snprintf(exp,size,"EV1 VERSION"); + } + break; + case MIFARE_AUTH_KEYB: + MifareAuthState = masNt; + snprintf(exp,size,"AUTH-B(%d)",cmd[1]); + break; + case MIFARE_MAGICWUPC1: snprintf(exp,size,"MAGIC WUPC1"); break; + case MIFARE_MAGICWUPC2: snprintf(exp,size,"MAGIC WUPC2"); break; + case MIFARE_MAGICWIPEC: snprintf(exp,size,"MAGIC WIPEC"); break; + case MIFARE_ULC_AUTH_1: snprintf(exp,size,"AUTH "); break; + case MIFARE_ULC_AUTH_2: snprintf(exp,size,"AUTH_ANSW"); break; + case MIFARE_ULEV1_AUTH: + if ( cmdsize == 7 ) + snprintf(exp,size,"PWD-AUTH KEY: 0x%02x%02x%02x%02x", cmd[1], cmd[2], cmd[3], cmd[4] ); + else + snprintf(exp,size,"PWD-AUTH"); + break; + case MIFARE_ULEV1_FASTREAD:{ + if ( cmdsize >=3 && cmd[2] <= 0xE6) + snprintf(exp,size,"READ RANGE (%d-%d)",cmd[1],cmd[2]); + else + snprintf(exp,size,"?"); + break; + } + case MIFARE_ULC_WRITE:{ + if ( cmd[1] < 0x21 ) + snprintf(exp,size,"WRITEBLOCK(%d)",cmd[1]); + else + snprintf(exp,size,"?"); + break; + } + case MIFARE_ULEV1_READ_CNT:{ + if ( cmd[1] < 5 ) + snprintf(exp,size,"READ CNT(%d)",cmd[1]); + else + snprintf(exp,size,"?"); + break; + } + case MIFARE_ULEV1_INCR_CNT:{ + if ( cmd[1] < 5 ) + snprintf(exp,size,"INCR(%d)",cmd[1]); + else + snprintf(exp,size,"?"); + break; + } + case MIFARE_ULEV1_READSIG: snprintf(exp,size,"READ_SIG"); break; + case MIFARE_ULEV1_CHECKTEAR: snprintf(exp,size,"CHK_TEARING(%d)",cmd[1]); break; + case MIFARE_ULEV1_VCSL: snprintf(exp,size,"VCSL"); break; + default: snprintf(exp,size,"?"); break; + } + return; +} + +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) { + ClearAuthData(); + AuthData.uid = bytes_to_num(&cmd[2], 4); + } + if (cmdsize == 9 && cmd[0] == ISO14443A_CMD_ANTICOLL_OR_SELECT_2 && cmd[1] == 0x70) { + ClearAuthData(); + AuthData.uid = bytes_to_num(&cmd[2], 4); + } + } + + switch(MifareAuthState) { + case masNt: + if (cmdsize == 4 && isResponse) { + snprintf(exp,size,"AUTH: nt %s", (AuthData.first_auth) ? "" : "(enc)"); + MifareAuthState = masNrAr; + if (AuthData.first_auth) { + AuthData.nt = bytes_to_num(cmd, 4); + } else { + AuthData.nt_enc = bytes_to_num(cmd, 4); + AuthData.nt_enc_par = parity[0]; + } + return; + } else { + MifareAuthState = masError; + } + break; + case masNrAr: + if (cmdsize == 8 && !isResponse) { + snprintf(exp,size,"AUTH: nr ar (enc)"); + MifareAuthState = masAt; + AuthData.nr_enc = bytes_to_num(cmd, 4); + AuthData.ar_enc = bytes_to_num(&cmd[4], 4); + AuthData.ar_enc_par = parity[0] << 4; + return; + } else { + MifareAuthState = masError; + } + break; + case masAt: + if (cmdsize == 4 && isResponse) { + snprintf(exp,size,"AUTH: at (enc)"); + MifareAuthState = masAuthComplete; + AuthData.at_enc = bytes_to_num(cmd, 4); + AuthData.at_enc_par = parity[0]; + return; + } else { + MifareAuthState = masError; + } + break; + default: + break; + } + + if (!isResponse && ((MifareAuthState == masNone) || (MifareAuthState == masError))) + annotateIso14443a(exp, size, cmd, cmdsize); + +} + +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; + + *mfDataLen = 0; + + if (MifareAuthState == masAuthComplete) { + if (traceCrypto1) { + crypto1_destroy(traceCrypto1); + traceCrypto1 = NULL; + } + + MifareAuthState = masFirstData; + return false; + } + + if (cmdsize > 32) + return false; + + if (MifareAuthState == masFirstData) { + if (AuthData.first_auth) { + AuthData.ks2 = AuthData.ar_enc ^ prng_successor(AuthData.nt, 64); + AuthData.ks3 = AuthData.at_enc ^ prng_successor(AuthData.nt, 96); + + mfLastKey = GetCrypto1ProbableKey(&AuthData); + PrintAndLog(" | * | key | probable key:%012"PRIx64" Prng:%s ks2:%08x ks3:%08x | |", + mfLastKey, + validate_prng_nonce(AuthData.nt) ? "WEAK": "HARD", + AuthData.ks2, + AuthData.ks3); + + AuthData.first_auth = false; + + traceCrypto1 = lfsr_recovery64(AuthData.ks2, AuthData.ks3); + } else { + if (traceCrypto1) { + crypto1_destroy(traceCrypto1); + traceCrypto1 = NULL; + } + + // check last used key + if (mfLastKey) { + if (NestedCheckKey(mfLastKey, &AuthData, cmd, cmdsize, parity)) { + PrintAndLog(" | * | key | last used key:%012"PRIx64" ks2:%08x ks3:%08x | |", + mfLastKey, + 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, parity)) { + PrintAndLog(" | * | key | default key:%012"PRIx64" ks2:%08x ks3:%08x | |", + MifareDefaultKeys[defaultKeyCounter], + AuthData.ks2, + AuthData.ks3); + + mfLastKey = MifareDefaultKeys[defaultKeyCounter]; + traceCrypto1 = lfsr_recovery64(AuthData.ks2, AuthData.ks3); + break; + }; + } + } + + // nested + if (!traceCrypto1 && validate_prng_nonce(AuthData.nt)) { + uint32_t ntx = prng_successor(AuthData.nt, 90); + for (int i = 0; i < 16383; i++) { + ntx = prng_successor(ntx, 1); + if (NTParityChk(&AuthData, ntx)){ + + uint32_t ks2 = AuthData.ar_enc ^ prng_successor(ntx, 64); + uint32_t ks3 = AuthData.at_enc ^ prng_successor(ntx, 96); + struct Crypto1State *pcs = lfsr_recovery64(ks2, ks3); + memcpy(mfData, cmd, cmdsize); + mf_crypto1_decrypt(pcs, mfData, cmdsize, 0); + + crypto1_destroy(pcs); + if (CheckCrypto1Parity(cmd, cmdsize, mfData, parity) && CheckCrc14443(CRC_14443_A, mfData, cmdsize)) { + AuthData.ks2 = ks2; + AuthData.ks3 = ks3; + + AuthData.nt = ntx; + mfLastKey = GetCrypto1ProbableKey(&AuthData); + PrintAndLog(" | * | key | nested probable key:%012"PRIx64" ks2:%08x ks3:%08x | |", + mfLastKey, + AuthData.ks2, + AuthData.ks3); + + traceCrypto1 = lfsr_recovery64(AuthData.ks2, AuthData.ks3); + break; + } + } + } + } + + //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); + MifareAuthState = masError; + + /* TOO SLOW( needs to have more strong filter. with this filter - aprox 4 mln tests + uint32_t t = msclock(); + uint32_t t1 = t; + int n = 0; + for (uint32_t i = 0; i < 0xFFFFFFFF; i++) { + if (NTParityChk(&AuthData, i)){ + + uint32_t ks2 = AuthData.ar_enc ^ prng_successor(i, 64); + uint32_t ks3 = AuthData.at_enc ^ prng_successor(i, 96); + struct Crypto1State *pcs = lfsr_recovery64(ks2, ks3); + + + + + n++; + + if (!(n % 100000)) { + printf("delta=%d n=%d ks2=%x ks3=%x \n", msclock() - t1 , n, ks2, ks3); + t1 = msclock(); + } + + } + } + printf("delta=%d n=%d\n", msclock() - t, n); + */ + } + } + + + + MifareAuthState = masData; + } + + if (MifareAuthState == masData && traceCrypto1) { + memcpy(mfData, cmd, cmdsize); + mf_crypto1_decrypt(traceCrypto1, mfData, cmdsize, 0); + *mfDataLen = cmdsize; + } + + return *mfDataLen > 0; +} + +bool NTParityChk(TAuthData *ad, uint32_t ntx) { + if ( + (oddparity8(ntx >> 8 & 0xff) ^ (ntx & 0x01) ^ ((ad->nt_enc_par >> 5) & 0x01) ^ (ad->nt_enc & 0x01)) || + (oddparity8(ntx >> 16 & 0xff) ^ (ntx >> 8 & 0x01) ^ ((ad->nt_enc_par >> 6) & 0x01) ^ (ad->nt_enc >> 8 & 0x01)) || + (oddparity8(ntx >> 24 & 0xff) ^ (ntx >> 16 & 0x01) ^ ((ad->nt_enc_par >> 7) & 0x01) ^ (ad->nt_enc >> 16 & 0x01)) + ) + return false; + + uint32_t ar = prng_successor(ntx, 64); + if ( + (oddparity8(ar >> 8 & 0xff) ^ (ar & 0x01) ^ ((ad->ar_enc_par >> 5) & 0x01) ^ (ad->ar_enc & 0x01)) || + (oddparity8(ar >> 16 & 0xff) ^ (ar >> 8 & 0x01) ^ ((ad->ar_enc_par >> 6) & 0x01) ^ (ad->ar_enc >> 8 & 0x01)) || + (oddparity8(ar >> 24 & 0xff) ^ (ar >> 16 & 0x01) ^ ((ad->ar_enc_par >> 7) & 0x01) ^ (ad->ar_enc >> 16 & 0x01)) + ) + return false; + + uint32_t at = prng_successor(ntx, 96); + if ( + (oddparity8(ar & 0xff) ^ (at >> 24 & 0x01) ^ ((ad->ar_enc_par >> 4) & 0x01) ^ (ad->at_enc >> 24 & 0x01)) || + (oddparity8(at >> 8 & 0xff) ^ (at & 0x01) ^ ((ad->at_enc_par >> 5) & 0x01) ^ (ad->at_enc & 0x01)) || + (oddparity8(at >> 16 & 0xff) ^ (at >> 8 & 0x01) ^ ((ad->at_enc_par >> 6) & 0x01) ^ (ad->at_enc >> 8 & 0x01)) || + (oddparity8(at >> 24 & 0xff) ^ (at >> 16 & 0x01) ^ ((ad->at_enc_par >> 7) & 0x01) ^ (ad->at_enc >> 16 & 0x01)) + ) + return false; + + return true; +} + +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); + + 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; + + 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 (!CheckCrypto1Parity(cmd, cmdsize, buf, parity)) + return false; + + if(!CheckCrc14443(CRC_14443_A, buf, cmdsize)) + return false; + + AuthData.nt = nt1; + AuthData.ks2 = AuthData.ar_enc ^ ar; + AuthData.ks3 = AuthData.at_enc ^ at; + + return true; +} + +bool CheckCrypto1Parity(uint8_t *cmd_enc, uint8_t cmdsize, uint8_t *cmd, uint8_t *parity_enc) { + for (int i = 0; i < cmdsize - 1; i++) { + if (oddparity8(cmd[i]) ^ (cmd[i + 1] & 0x01) ^ ((parity_enc[i / 8] >> (7 - i % 8)) & 0x01) ^ (cmd_enc[i + 1] & 0x01)) + return false; + } + + return true; +} + +uint64_t GetCrypto1ProbableKey(TAuthData *ad) { + struct Crypto1State *revstate = lfsr_recovery64(ad->ks2, ad->ks3); + lfsr_rollback_word(revstate, 0, 0); + lfsr_rollback_word(revstate, 0, 0); + lfsr_rollback_word(revstate, ad->nr_enc, 1); + lfsr_rollback_word(revstate, ad->uid ^ ad->nt, 0); + + uint64_t lfsr = 0; + crypto1_get_lfsr(revstate, &lfsr); + crypto1_destroy(revstate); + + return lfsr; +}