From 516dbac2105d8195ba52f46f4d5d75d598868f45 Mon Sep 17 00:00:00 2001 From: iceman1001 Date: Thu, 16 Feb 2017 19:48:50 +0100 Subject: [PATCH] CHG: `lf em` - some minor refactoring in 4x50 commands --- client/cmdlfem4x.c | 160 ++++++++++++++++++++++----------------------- 1 file changed, 79 insertions(+), 81 deletions(-) diff --git a/client/cmdlfem4x.c b/client/cmdlfem4x.c index ad35d904..d38c2543 100644 --- a/client/cmdlfem4x.c +++ b/client/cmdlfem4x.c @@ -305,7 +305,6 @@ uint32_t OutputEM4x50_Block(uint8_t *BitStream, size_t size, bool verbose, bool //completed by Marshmellow int EM4x50Read(const char *Cmd, bool verbose) { - uint8_t fndClk[] = {8,16,32,40,50,64,128}; int clk = 0; int invert = 0; @@ -500,7 +499,7 @@ int CmdEM4x50Read(const char *Cmd) { } int usage_lf_em_read(void) { - PrintAndLog("Read EM4x05/EM4x69. Tag must be on antenna. "); + PrintAndLog("Read EM 4x05/4x50/EM4x69. Tag must be on antenna. "); PrintAndLog(""); PrintAndLog("Usage: lf em readword [h]
"); PrintAndLog("Options:"); @@ -513,27 +512,69 @@ int usage_lf_em_read(void) { return 0; } +int usage_lf_em_write(void) { + PrintAndLog("Write EM 4x05/4x50/4x69. Tag must be on antenna. "); + PrintAndLog(""); + PrintAndLog("Usage: lf em writeword [h]
"); + PrintAndLog("Options:"); + PrintAndLog(" h - this help"); + PrintAndLog(" address - memory address to write to. (0-15)"); + PrintAndLog(" data - data to write (hex)"); + PrintAndLog(" pwd - password (hex) (optional)"); + PrintAndLog("samples:"); + PrintAndLog(" lf em writeword 1"); + PrintAndLog(" lf em writeword 1 deadc0de 11223344"); + return 0; +} + +#define EM_PREAMBLE_LEN 6 +// download samples from device +// and copy them to Graphbuffer +bool downloadSamplesEM(){ + + // 8 bit preamble + 32 bit word response (max clock (128) * 40bits = 5120 samples) + uint8_t got[6000]; + GetFromBigBuf(got, sizeof(got), 0); + if ( !WaitForResponseTimeout(CMD_ACK, NULL, 2500) ) { + PrintAndLog("command execution time out"); + return FALSE; + } + setGraphBuf(got, sizeof(got)); + return TRUE; +} //search for given preamble in given BitStream and return success=1 or fail=0 and startIndex -uint8_t EMpreambleSearch(uint8_t *BitStream, uint8_t *preamble, size_t pLen, size_t size, size_t *startIdx) { - // Sanity check. If preamble length is bigger than bitstream length. - if ( size <= pLen ) return 0; +bool doPreambleSearch(size_t *startIdx){ + + // sanity check + if ( DemodBufferLen < EM_PREAMBLE_LEN) + return FALSE; + + // skip first two 0 bits as they might have been missed in the demod + uint8_t preamble[EM_PREAMBLE_LEN] = {0,0,1,0,1,0}; + + // set size to 10 to only test first 4 positions for the preamble + size_t size = (10 > DemodBufferLen) ? DemodBufferLen : 10; + *startIdx = 0; + uint8_t found = 0; // em only sends preamble once, so look for it once in the first x bits - uint8_t foundCnt = 0; - for (int idx = 0; idx < size - pLen; idx++){ - if (memcmp(BitStream+idx, preamble, pLen) == 0){ + for (int idx = 0; idx < size - EM_PREAMBLE_LEN; idx++){ + if (memcmp(DemodBuffer+idx, preamble, EM_PREAMBLE_LEN) == 0){ //first index found - foundCnt++; - if (foundCnt == 1) { - *startIdx = idx; - return 1; - } + *startIdx = idx; + found = 1; + break; } } - return 0; + + if ( !found) { + if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", *startIdx); + return FALSE; + } + + return TRUE; } -#define EM_PREAMBLE_LEN 6 bool detectFSK(){ // detect fsk clock if (!GetFskClock("", FALSE, FALSE)) { @@ -581,24 +622,15 @@ bool detectASK_BI(){ } return TRUE; } -bool doPreambleSearch(size_t *startIdx){ - // skip first two 0 bits as they might have been missed in the demod - uint8_t preamble[EM_PREAMBLE_LEN] = {0,0,1,0,1,0}; - - // set size to 10 to only test first 4 positions for the preamble - size_t size = (10 > DemodBufferLen) ? DemodBufferLen : 10; - *startIdx = 0; - - if (g_debugMode) PrintAndLog("Before:: startindex: %u | size: %u", *startIdx, size); - - uint8_t errChk = !EMpreambleSearch(DemodBuffer, preamble, EM_PREAMBLE_LEN, size, startIdx); - if ( errChk == 0) { - if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", *startIdx); - return FALSE; - } - if (g_debugMode) PrintAndLog("After:: startindex: %u | size: %u", *startIdx, size); - return TRUE; +// param: idx - start index in demoded data. +int setDemodBufferEM(uint8_t bitsNeeded, size_t idx){ + if ( bitsNeeded < DemodBufferLen) { + setDemodBuf(DemodBuffer + idx + EM_PREAMBLE_LEN, bitsNeeded, 0); + CmdPrintDemodBuff("x"); + return 1; + } + return -1; } // FSK, PSK, ASK/MANCHESTER, ASK/BIPHASE, ASK/DIPHASE @@ -609,27 +641,18 @@ int demodEM4x05resp(uint8_t bitsNeeded) { size_t startIdx = 0; if (detectASK_MAN() && doPreambleSearch( &startIdx )) - goto EXIT_SET; + return setDemodBufferEM(bitsNeeded, startIdx); if (detectASK_BI() && doPreambleSearch( &startIdx )) - goto EXIT_SET; + return setDemodBufferEM(bitsNeeded, startIdx); if (detectFSK() && doPreambleSearch( &startIdx )) - goto EXIT_SET; + return setDemodBufferEM(bitsNeeded, startIdx); - - if (detectPSK() && doPreambleSearch( &startIdx )) - goto EXIT_SET; + if (detectPSK() && doPreambleSearch( &startIdx )) + return setDemodBufferEM(bitsNeeded, startIdx); return -1; - -EXIT_SET: - if ( bitsNeeded < DemodBufferLen) { - setDemodBuf(DemodBuffer + startIdx + EM_PREAMBLE_LEN, bitsNeeded, 0); - CmdPrintDemodBuff("x"); - return 1; - } - return -1; } int CmdReadWord(const char *Cmd) { @@ -660,17 +683,13 @@ int CmdReadWord(const char *Cmd) { PrintAndLog("Command timed out"); return -1; } - - uint8_t got[6000]; - GetFromBigBuf(got, sizeof(got), 0); - if ( !WaitForResponseTimeout(CMD_ACK, NULL, 2500) ) { - PrintAndLog("command execution time out"); + + if (!downloadSamplesEM()) return -1; - } - setGraphBuf(got, sizeof(got)); + int testLen = (GraphTraceLen < 1000) ? GraphTraceLen : 1000; if (graphJustNoise(GraphBuffer, testLen)) { - PrintAndLog("no tag not found"); + PrintAndLog("Tag not found"); return -1; } @@ -679,26 +698,11 @@ int CmdReadWord(const char *Cmd) { return demodEM4x05resp(32); } -int usage_lf_em_write(void) { - PrintAndLog("Write EM4x05/EM4x69. Tag must be on antenna. "); - PrintAndLog(""); - PrintAndLog("Usage: lf em writeword [h]
"); - PrintAndLog("Options:"); - PrintAndLog(" h - this help"); - PrintAndLog(" address - memory address to write to. (0-15)"); - PrintAndLog(" data - data to write (hex)"); - PrintAndLog(" pwd - password (hex) (optional)"); - PrintAndLog("samples:"); - PrintAndLog(" lf em writeword 1"); - PrintAndLog(" lf em writeword 1 deadc0de 11223344"); - return 0; -} int CmdWriteWord(const char *Cmd) { uint8_t ctmp = param_getchar(Cmd, 0); if ( strlen(Cmd) == 0 || ctmp == 'H' || ctmp == 'h' ) return usage_lf_em_write(); - bool usePwd = false; - + bool usePwd = false; int addr = 16; // default to invalid address int data = 0xFFFFFFFF; // default to blank data int pwd = 0xFFFFFFFF; // default to blank password @@ -729,23 +733,17 @@ int CmdWriteWord(const char *Cmd) { return -1; } - //get response if there is one - uint8_t got[6000]; // 8 bit preamble + 32 bit word response (max clock (128) * 40bits = 5120 samples) - GetFromBigBuf(got, sizeof(got), 0); - if ( !WaitForResponseTimeout(CMD_ACK, NULL, 2500) ) { - PrintAndLog("command execution time out"); - return -2; - } - setGraphBuf(got, sizeof(got)); - + if (!downloadSamplesEM()) + return -1; + //todo: check response for 00001010 then write data for write confirmation! //attempt demod: //need 0 bits demoded (after preamble) to verify write cmd int result = demodEM4x05resp(0); - if (result == 1) { + if (result == 1) PrintAndLog("Write Verified"); - } + return result; } -- 2.39.2