From: pwpiwi Date: Wed, 23 Oct 2019 07:09:13 +0000 (+0200) Subject: iso14443b: trying to approach iClass X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/commitdiff_plain/a3bef9863b9e06a820c7559b9caffeaaa1bb575b iso14443b: trying to approach iClass * decode and handle SOF only responses in Handle14443bSamplesDemod() * allow 1 byte commands with 'hf 14b raw' --- diff --git a/armsrc/iso14443b.c b/armsrc/iso14443b.c index f276158f..6434409d 100644 --- a/armsrc/iso14443b.c +++ b/armsrc/iso14443b.c @@ -586,9 +586,10 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq) Demod.state = DEMOD_UNSYNCD; } else { LED_C_ON(); // Got SOF - Demod.state = DEMOD_AWAITING_START_BIT; Demod.posCount = 0; + Demod.bitCount = 0; Demod.len = 0; + Demod.state = DEMOD_AWAITING_START_BIT; /* this had been used to add RSSI (Received Signal Strength Indication) to traces. Currently not implemented. Demod.metricN = 0; Demod.metric = 0; @@ -605,13 +606,16 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq) case DEMOD_AWAITING_START_BIT: Demod.posCount++; MAKE_SOFT_DECISION(); - if(v > 0) { - if(Demod.posCount > 3*2) { // max 19us between characters = 16 1/fs, max 3 etu after low phase of SOF = 24 1/fs - Demod.state = DEMOD_UNSYNCD; + if (v > 0) { + if (Demod.posCount > 3*2) { // max 19us between characters = 16 1/fs, max 3 etu after low phase of SOF = 24 1/fs LED_C_OFF(); + if (Demod.bitCount == 0 && Demod.len == 0) { // received SOF only, this is valid for iClass/Picopass + return true; + } else { + Demod.state = DEMOD_UNSYNCD; + } } } else { // start bit detected - Demod.bitCount = 0; Demod.posCount = 1; // this was the first half Demod.thisBit = v; Demod.shiftReg = 0; @@ -621,7 +625,7 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq) case DEMOD_RECEIVING_DATA: MAKE_SOFT_DECISION(); - if(Demod.posCount == 0) { // first half of bit + if (Demod.posCount == 0) { // first half of bit Demod.thisBit = v; Demod.posCount = 1; } else { // second half of bit @@ -637,22 +641,23 @@ static RAMFUNC int Handle14443bSamplesDemod(int ci, int cq) */ Demod.shiftReg >>= 1; - if(Demod.thisBit > 0) { // logic '1' + if (Demod.thisBit > 0) { // logic '1' Demod.shiftReg |= 0x200; } Demod.bitCount++; - if(Demod.bitCount == 10) { + if (Demod.bitCount == 10) { uint16_t s = Demod.shiftReg; - if((s & 0x200) && !(s & 0x001)) { // stop bit == '1', start bit == '0' + if ((s & 0x200) && !(s & 0x001)) { // stop bit == '1', start bit == '0' uint8_t b = (s >> 1); Demod.output[Demod.len] = b; Demod.len++; + Demod.bitCount = 0; Demod.state = DEMOD_AWAITING_START_BIT; } else { Demod.state = DEMOD_UNSYNCD; LED_C_OFF(); - if(s == 0x000) { + if (s == 0x000) { // This is EOF (start, stop and all data bits == '0' return true; } @@ -693,8 +698,8 @@ static void DemodInit(uint8_t *data) * Demodulate the samples we received from the tag, also log to tracebuffer * quiet: set to 'true' to disable debug output */ -static void GetSamplesFor14443bDemod(int timeout, bool quiet) -{ +static int GetSamplesFor14443bDemod(int timeout, bool quiet) { + int ret = 0; int maxBehindBy = 0; bool gotFrame = false; int lastRxCounter, samples = 0; @@ -750,12 +755,14 @@ static void GetSamplesFor14443bDemod(int timeout, bool quiet) } samples++; - if(Handle14443bSamplesDemod(ci, cq)) { + if (Handle14443bSamplesDemod(ci, cq)) { + ret = Demod.len; gotFrame = true; break; } if(samples > timeout && Demod.state < DEMOD_PHASE_REF_TRAINING) { + ret = -1; LED_C_OFF(); break; } @@ -764,10 +771,14 @@ static void GetSamplesFor14443bDemod(int timeout, bool quiet) FpgaDisableSscDma(); if (!quiet) Dbprintf("max behindby = %d, samples = %d, gotFrame = %d, Demod.len = %d, Demod.sumI = %d, Demod.sumQ = %d", maxBehindBy, samples, gotFrame, Demod.len, Demod.sumI, Demod.sumQ); - //Tracing - if (Demod.len > 0) { - LogTrace(Demod.output, Demod.len, 0, 0, NULL, false); + + if (ret < 0) { + return ret; } + //Tracing + LogTrace(Demod.output, Demod.len, 0, 0, NULL, false); + + return ret; } @@ -858,8 +869,7 @@ static void CodeAndTransmit14443bAsReader(const uint8_t *cmd, int len) /* Sends an APDU to the tag * TODO: check CRC and preamble */ -int iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *response) -{ +int iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *response) { LED_A_ON(); uint8_t message_frame[message_length + 4]; // PCB @@ -874,21 +884,19 @@ int iso14443b_apdu(uint8_t const *message, size_t message_length, uint8_t *respo // send CodeAndTransmit14443bAsReader(message_frame, message_length + 4); // get response - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + int ret = GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); FpgaDisableTracing(); - if(Demod.len < 3) - { + if (ret < 3) { LED_A_OFF(); return 0; } // TODO: Check CRC // copy response contents - if(response != NULL) - { + if (response != NULL) { memcpy(response, Demod.output, Demod.len); } LED_A_OFF(); - return Demod.len; + return ret; } /* Perform the ISO 14443 B Card Selection procedure @@ -907,10 +915,9 @@ int iso14443b_select_card() // first, wake up the tag CodeAndTransmit14443bAsReader(wupb, sizeof(wupb)); - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + int ret = GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); // ATQB too short? - if (Demod.len < 14) - { + if (ret < 14) { return 2; } @@ -922,10 +929,9 @@ int iso14443b_select_card() attrib[7] = Demod.output[10] & 0x0F; ComputeCrc14443(CRC_14443_B, attrib, 9, attrib + 9, attrib + 10); CodeAndTransmit14443bAsReader(attrib, sizeof(attrib)); - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + ret = GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); // Answer to ATTRIB too short? - if(Demod.len < 3) - { + if (ret < 3) { return 2; } // reset PCB block number @@ -985,9 +991,9 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) // First command: wake up the tag using the INITIATE command uint8_t cmd1[] = {0x06, 0x00, 0x97, 0x5b}; CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + int ret = GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); - if (Demod.len == 0) { + if (ret < 0) { FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); DbpString("No response from tag"); LEDsoff(); @@ -1003,7 +1009,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) cmd1[1] = Demod.output[0]; ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]); CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + ret = GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); if (Demod.len != 3) { FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); Dbprintf("Expected 3 bytes from tag, got %d", Demod.len); @@ -1031,8 +1037,8 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) cmd1[0] = 0x0B; ComputeCrc14443(CRC_14443_B, cmd1, 1 , &cmd1[1], &cmd1[2]); CodeAndTransmit14443bAsReader(cmd1, 3); // Only first three bytes for this one - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); - if (Demod.len != 10) { + ret = GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + if (ret != 10) { FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); Dbprintf("Expected 10 bytes from tag, got %d", Demod.len); LEDsoff(); @@ -1062,8 +1068,8 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) cmd1[1] = i; ComputeCrc14443(CRC_14443_B, cmd1, 2, &cmd1[2], &cmd1[3]); CodeAndTransmit14443bAsReader(cmd1, sizeof(cmd1)); - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); - if (Demod.len != 6) { // Check if we got an answer from the tag + ret = GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + if (ret != 6) { // Check if we got an answer from the tag FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); DbpString("Expected 6 bytes from tag, got less..."); LEDsoff(); @@ -1071,7 +1077,7 @@ void ReadSTMemoryIso14443b(uint32_t dwLast) } // The check the CRC of the answer (use cmd1 as temporary variable): ComputeCrc14443(CRC_14443_B, Demod.output, 4, &cmd1[2], &cmd1[3]); - if(cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) { + if (cmd1[2] != Demod.output[4] || cmd1[3] != Demod.output[5]) { Dbprintf("CRC Error reading block! Expected: %04x got: %04x", (cmd1[2]<<8)+cmd1[3], (Demod.output[4]<<8)+Demod.output[5]); // Do not return;, let's go on... (we should retry, maybe ?) @@ -1213,8 +1219,8 @@ void RAMFUNC SnoopIso14443b(void) ReaderIsActive = (Uart.state > STATE_GOT_FALLING_EDGE_OF_SOF); } - if(!ReaderIsActive && triggered) { // no need to try decoding tag data if the reader is sending or not yet triggered - if(Handle14443bSamplesDemod(ci/2, cq/2)) { + if (!ReaderIsActive && triggered) { // no need to try decoding tag data if the reader is sending or not yet triggered + if (Handle14443bSamplesDemod(ci/2, cq/2) >= 0) { //Use samples as a time measurement LogTrace(Demod.output, Demod.len, samples, samples, NULL, false); // And ready to receive another response. @@ -1265,17 +1271,17 @@ void SendRawCommand14443B(uint32_t datalen, uint32_t recv, uint8_t powerfield, u CodeAndTransmit14443bAsReader(data, datalen); - if(recv) { - GetSamplesFor14443bDemod(RECEIVE_SAMPLES_TIMEOUT, true); + if (recv) { + int ret = GetSamplesFor14443bDemod(5*RECEIVE_SAMPLES_TIMEOUT, true); FpgaDisableTracing(); uint16_t iLen = MIN(Demod.len, USB_CMD_DATA_SIZE); - cmd_send(CMD_ACK, iLen, 0, 0, Demod.output, iLen); + cmd_send(CMD_ACK, ret, 0, 0, Demod.output, iLen); } FpgaDisableTracing(); } - if(!powerfield) { + if (!powerfield) { FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF); LED_D_OFF(); } diff --git a/client/cmdhf14b.c b/client/cmdhf14b.c index 8a83df8f..4685f3f5 100644 --- a/client/cmdhf14b.c +++ b/client/cmdhf14b.c @@ -108,9 +108,21 @@ int HF14BCmdRaw(bool reply, bool *crc, bool power, uint8_t *data, uint8_t *datal if (verbose) PrintAndLog("timeout while waiting for reply."); return 0; } - *datalen = resp.arg[0]; - if (verbose) PrintAndLog("received %u octets", *datalen); - if (*datalen < 2) return 0; + + int ret = resp.arg[0]; + if (verbose) { + if (ret < 0) { + PrintAndLog("tag didn't respond"); + } else if (ret == 0) { + PrintAndLog("received SOF only (maybe iCLASS/Picopass)"); + } else { + PrintAndLog("received %u octets", ret); + } + } + + *datalen = ret; + + if (ret < 2) return 0; memcpy(data, resp.d.asBytes, *datalen); if (verbose) PrintAndLog("%s", sprint_hex(data, *datalen)); @@ -139,7 +151,7 @@ static int CmdHF14BCmdRaw (const char *Cmd) { uint8_t datalen = 0; unsigned int temp; int i = 0; - if (strlen(Cmd) < 3) { + if (strlen(Cmd) < 2) { PrintAndLog("Usage: hf 14b raw [-r] [-c] [-p] [-s || -ss] <0A 0B 0C ... hex>"); PrintAndLog(" -r do not read response"); PrintAndLog(" -c calculate and append CRC");