}
int usage_lf_em_read(void) {
- PrintAndLog("Read EM4x50. Tag must be on antenna. ");
+ PrintAndLog("Read EM4x05/EM4x69. Tag must be on antenna. ");
PrintAndLog("");
PrintAndLog("Usage: lf em readword [h] <address> <pwd>");
PrintAndLog("Options:");
PrintAndLog(" lf em readword 1 11223344");
return 0;
}
+
+//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;
+
+ // 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){
+ //first index found
+ foundCnt++;
+ if (foundCnt == 1) {
+ *startIdx = idx;
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+
+#define EM_PREAMBLE_LEN 6
+bool detectFSK(){
+ // detect fsk clock
+ if (!GetFskClock("", FALSE, FALSE)) {
+ if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: FSK clock failed");
+ return FALSE;
+ }
+ // demod
+ int ans = FSKrawDemod("0 0", FALSE);
+ if (!ans) {
+ if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: FSK Demod failed");
+ return FALSE;
+ }
+ return TRUE;
+}
+// PSK clocks should be easy to detect ( but difficult to demod a non-repeating pattern... )
+bool detectPSK(){
+ int ans = GetPskClock("", FALSE, FALSE);
+ if (!ans) {
+ if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: PSK clock failed");
+ return FALSE;
+ }
+ PrintAndLog("PSK response possibly found, run `data rawd p1` to attempt to demod");
+ return TRUE;
+}
+// try manchester - NOTE: ST only applies to T55x7 tags.
+bool detectASK_MAN(){
+ bool stcheck = FALSE;
+ int ans = ASKDemod_ext("0 0 0", TRUE, FALSE, 1, &stcheck);
+ if (!ans) {
+ if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/Manchester Demod failed");
+ return FALSE;
+ }
+ return TRUE;
+}
+bool detectASK_BI(){
+ int ans = ASKbiphaseDemod("0 0 1", FALSE);
+ if (!ans) {
+ if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/biphase normal demod failed");
+
+ ans = ASKbiphaseDemod("0 1 1", FALSE);
+ if (!ans) {
+ if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/biphase inverted demod failed");
+ return FALSE;
+ }
+ }
+ 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;
+}
+
+// FSK, PSK, ASK/MANCHESTER, ASK/BIPHASE, ASK/DIPHASE
+// should cover 90% of known used configs
+// the rest will need to be manually demoded for now...
+int demodEM4x05resp(uint8_t bitsNeeded) {
+
+ size_t startIdx = 0;
+
+ if (detectASK_MAN() && doPreambleSearch( &startIdx ))
+ goto EXIT_SET;
+
+ if (detectASK_BI() && doPreambleSearch( &startIdx ))
+ goto EXIT_SET;
+
+ if (detectFSK() && doPreambleSearch( &startIdx ))
+ goto EXIT_SET;
+
+
+ if (detectPSK() && doPreambleSearch( &startIdx ))
+ goto EXIT_SET;
+
+ 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) {
int addr, pwd;
bool usePwd = false;
return -1;
}
setGraphBuf(got, sizeof(got));
-
-
- int ans = 0;
- //bool ST = true;
- DemodBufferLen = 0x00;
-
- //ans = ASKDemod_ext("0 0 1", FALSE, FALSE, 1, &ST);
- ans = ASKbiphaseDemod("0 0 1", FALSE);
- if (!ans) {
- if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/Manchester Demod failed");
- return -1;
- }
-
- size_t startIdx = 0, size = DemodBufferLen;
-
- PrintAndLog("ANS: %d | %u | %u", ans, startIdx, size);
-
-
- uint8_t preamble[8] = {0,0,0,0,1,0,1,0};
- uint8_t errChk = !preambleSearch(DemodBuffer, preamble, sizeof(preamble), &size, &startIdx);
- if ( errChk == 0) {
- if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", startIdx);
- return -1;
- }
-
- // sanity check.
- if (size != 32) {
- if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 incorrect data length found, %u", size );
+ int testLen = (GraphTraceLen < 1000) ? GraphTraceLen : 1000;
+ if (graphJustNoise(GraphBuffer, testLen)) {
+ PrintAndLog("no tag not found");
return -1;
}
- //setDemodBuf(BitStream, 32, preambleIndex);
-
- return 1;
+ //attempt demod:
+ //need 32 bits from a read word
+ return demodEM4x05resp(32);
}
int usage_lf_em_write(void) {
- PrintAndLog("Write EM4x50. Tag must be on antenna. ");
+ PrintAndLog("Write EM4x05/EM4x69. Tag must be on antenna. ");
PrintAndLog("");
PrintAndLog("Usage: lf em writeword [h] <address> <data> <pwd>");
PrintAndLog("Options:");
data = param_get32ex(Cmd, 1, -1, 16);
pwd = param_get32ex(Cmd, 2, -1, 16);
-
if ( (addr > 15) || (addr < 0 ) || ( addr == -1) ) {
PrintAndLog("Address must be between 0 and 15");
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, 8000) ) {
+ if ( !WaitForResponseTimeout(CMD_ACK, NULL, 2500) ) {
PrintAndLog("command execution time out");
return -2;
}
setGraphBuf(got, sizeof(got));
- int ans = 0;
- //bool ST = true;
- DemodBufferLen = 0x00;
-
- //ans = ASKDemod_ext("0 0 1", FALSE, FALSE, 1, &ST);
- ans = ASKbiphaseDemod("0 0 1", FALSE);
- if (!ans) {
- if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305: ASK/Manchester Demod failed");
- return -3;
- }
- PrintAndLog("ANS: %d", ans);
+ //todo: check response for 00001010 then write data for write confirmation!
- //todo: check response for 00001010 then write data for write confirmation!
- size_t startIdx = 0, size = DemodBufferLen;
-
- uint8_t preamble[8] = {0,0,0,0,1,0,1,0};
- if (!preambleSearch(DemodBuffer, preamble, sizeof(preamble), &size, &startIdx)){
- if (g_debugMode) PrintAndLog("DEBUG: Error - EM4305 preamble not found :: %d", startIdx);
- return -4;
+ //attempt demod:
+ //need 0 bits demoded (after preamble) to verify write cmd
+ int result = demodEM4x05resp(0);
+ if (result == 1) {
+ PrintAndLog("Write Verified");
}
- PrintAndLog("Write OK");
- return 0;
+ return result;
}
static command_t CommandTable[] = {
projects / proxmark3-svn / blobdiff