From ab20cc35b7cef4e69a4e74f2b59d9e9b7fe2d022 Mon Sep 17 00:00:00 2001 From: Michael Farrell Date: Tue, 31 Jul 2018 03:33:06 +1000 Subject: [PATCH 1/1] Adds `lf hid pack` and `lf hid unpack` offline commands. (#614) * These are used to pack and unpack the bit length, facility code and card number from "short" HID Prox IDs. * This also simplifies some repeated code that is used to parse hex digits in lfhid, and adds basic client-side validation to the `lf hid clone` and `lf hid sim` commands, for when an ID that is too long is entered. * Implements parity checks/calculation for 26-bit H10301 cards. * Adds links to useful resources for HID Prox cards. * Adds an explicit warning about the lack of parities on non-26-bit cards. * Changes all the examples to use 26-bit IDs that have a parity bit set. --- client/cmdlfhid.c | 326 ++++++++++++++++++++++++++++++++++++++-------- client/cmdlfhid.h | 29 +++++ 2 files changed, 300 insertions(+), 55 deletions(-) diff --git a/client/cmdlfhid.c b/client/cmdlfhid.c index ca58d8ab..433a093d 100644 --- a/client/cmdlfhid.c +++ b/client/cmdlfhid.c @@ -6,6 +6,16 @@ // the license. //----------------------------------------------------------------------------- // Low frequency HID commands (known) +// +// Useful resources: +// RF interface, programming a T55x7 clone, 26-bit HID H10301 encoding: +// http://www.proxmark.org/files/Documents/125%20kHz%20-%20HID/HID_format_example.pdf +// +// "Understanding Card Data Formats" +// https://www.hidglobal.com/sites/default/files/hid-understanding_card_data_formats-wp-en.pdf +// +// "What Format Do You Need?" +// https://www.hidglobal.com/sites/default/files/resource_files/hid-prox-br-en.pdf //----------------------------------------------------------------------------- #include "cmdlfhid.h" @@ -18,9 +28,171 @@ #include "cmdparser.h" #include "cmddata.h" //for g_debugMode, demodbuff cmds #include "lfdemod.h" // for HIDdemodFSK +#include "parity.h" // for parity +#include "util.h" // for param_get8,32 static int CmdHelp(const char *Cmd); + +/** + * Packs a "short" (<38-bit) HID ID from component parts. + * + * This only works with 26, 34, 35 and 37 bit card IDs. + * + * NOTE: Parity calculation is only supported on 26-bit tags. Other card lengths + * may have invalid parity. + * + * Returns false on invalid inputs. + */ +bool pack_short_hid(/* out */ uint32_t *hi, /* out */ uint32_t *lo, /* in */ const short_hid_info *info) { + uint32_t high = 0, low = 0; + + switch (info->fmtLen) { + case 26: // HID H10301 + low |= (info->cardnum & 0xffff) << 1; + low |= (info->fc & 0xff) << 17; + + if (info->parityValid) { + // Calculate parity + low |= oddparity32((low >> 1) & 0xfff) & 1; + low |= (evenparity32((low >> 13) & 0xfff) & 1) << 25; + } + break; + + case 34: + low |= (info->cardnum & 0xffff) << 1; + low |= (info->fc & 0x7fff) << 17; + high |= (info->fc & 0x8000) >> 15; + // TODO: Calculate parity + break; + + case 35: + low |= (info->cardnum & 0xfffff) << 1; + low |= (info->fc & 0x7ff) << 21; + high |= (info->fc & 0x800) >> 11; + // TODO: Calculate parity + break; + + case 37: + low |= (info->cardnum & 0x7ffff) << 1; + low |= (info->fc & 0xfff) << 20; + high |= (info->fc & 0xf000) >> 12; + // TODO: Calculate parity + break; + + default: + // Invalid / unsupported length + return false; + } + + // Set the highest bit + if (info->fmtLen != 37) { + // Bit 37 is always set + high |= 0x20; + + // Set the bit corresponding to the length. + if (info->fmtLen < 32) { + low |= 1 << info->fmtLen; + } else { + high |= 1 << (info->fmtLen - 32); + } + } + + // Return result only if successful. + *hi = high; + *lo = low; + return true; +} + + +/** + * Unpacks a "short" (<38-bit) HID ID into its component parts. + * + * This only works with 26, 34, 35 and 37 bit card IDs. + * + * NOTE: Parity checking is only supported on 26-bit tags. + * + * Returns false on invalid inputs. + */ +bool unpack_short_hid(short_hid_info *out, uint32_t hi, uint32_t lo) { + memset(out, 0, sizeof(short_hid_info)); + + if (((hi >> 5) & 1) == 1) { + // if bit 38 is set then < 37 bit format is used + uint32_t lo2 = 0; + // get bits 21-37 to check for format len bit + lo2 = (((hi & 31) << 12) | (lo >> 20)); + uint8_t idx3 = 1; + // find last bit set to 1 (format len bit) + while (lo2 > 1) { + lo2 = lo2 >> 1; + idx3++; + } + + out->fmtLen = idx3 + 19; + + switch (out->fmtLen) { + case 26: // HID H10301 + out->cardnum = (lo >> 1) & 0xFFFF; + out->fc = (lo >> 17) & 0xFF; + + if (g_debugMode) { + PrintAndLog("oddparity : input=%x, calculated=%d, provided=%d", + (lo >> 1) & 0xFFF, oddparity32((lo >> 1) & 0xFFF), lo & 1); + PrintAndLog("evenparity: input=%x, calculated=%d, provided=%d", + (lo >> 13) & 0xFFF, evenparity32((lo >> 13) & 0xFFF) & 1, (lo >> 25) & 1); + } + + out->parityValid = + (oddparity32((lo >> 1) & 0xFFF) == (lo & 1)) && + ((evenparity32((lo >> 13) & 0xFFF) & 1) == ((lo >> 25) & 1)); + break; + + case 34: + out->cardnum = (lo >> 1) & 0xFFFF; + out->fc = ((hi & 1) << 15) | (lo >> 17); + // TODO: Calculate parity + break; + + case 35: + out->cardnum = (lo >> 1) & 0xFFFFF; + out->fc = ((hi & 1) << 11) | (lo >> 21); + // TODO: Calculate parity + break; + + default: + return false; + } + } else { + // If bit 38 is not set, then 37 bit format is used + out->fmtLen = 37; + out->cardnum = (lo >> 1) & 0x7FFFF; + out->fc = ((hi & 0xF) << 12) | (lo >> 20); + // TODO: Calculate parity + } + return true; +} + + +/** + * Converts a hex string to component "hi" and "lo" 32-bit integers, one nibble + * at a time. + * + * Returns the number of nibbles (4 bits) entered. + */ +int hexstring_to_int64(/* out */ uint32_t* hi, /* out */ uint32_t* lo, const char* str) { + // TODO: Replace this with param_gethex when it supports arbitrary length + // inputs. + int n = 0, i = 0; + + while (sscanf(&str[i++], "%1x", &n ) == 1) { + *hi = (*hi << 4) | (*lo >> 28); + *lo = (*lo << 4) | (n & 0xf); + } + + return i - 1; +} + //by marshmellow (based on existing demod + holiman's refactor) //HID Prox demod - FSK RF/50 with preamble of 00011101 (then manchester encoded) //print full HID Prox ID and some bit format details if found @@ -60,45 +232,19 @@ int CmdFSKdemodHID(const char *Cmd) (unsigned int) hi2, (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF); } else { //standard HID tags <38 bits - uint8_t fmtLen = 0; - uint32_t fc = 0; - uint32_t cardnum = 0; - if (((hi>>5)&1)==1){//if bit 38 is set then < 37 bit format is used - uint32_t lo2=0; - lo2=(((hi & 31) << 12) | (lo>>20)); //get bits 21-37 to check for format len bit - uint8_t idx3 = 1; - while(lo2>1){ //find last bit set to 1 (format len bit) - lo2=lo2>>1; - idx3++; - } - fmtLen =idx3+19; - fc =0; - cardnum=0; - if(fmtLen==26){ - cardnum = (lo>>1)&0xFFFF; - fc = (lo>>17)&0xFF; - } - if(fmtLen==34){ - cardnum = (lo>>1)&0xFFFF; - fc= ((hi&1)<<15)|(lo>>17); - } - if(fmtLen==35){ - cardnum = (lo>>1)&0xFFFFF; - fc = ((hi&1)<<11)|(lo>>21); - } + short_hid_info card_info; + bool ret = unpack_short_hid(&card_info, (uint32_t)hi, (uint32_t)lo); + PrintAndLog("HID Prox TAG ID: %x%08x (%d) - Format Len: %u bits - FC: %u - Card: %u", + (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF, + card_info.fmtLen, card_info.fc, card_info.cardnum); + + if (card_info.fmtLen == 26) { + PrintAndLog("Parity: %s", card_info.parityValid ? "valid" : "invalid"); } - else { //if bit 38 is not set then 37 bit format is used - fmtLen = 37; - fc = 0; - cardnum = 0; - if(fmtLen == 37){ - cardnum = (lo>>1)&0x7FFFF; - fc = ((hi&0xF)<<12)|(lo>>20); - } + + if (!ret) { + PrintAndLog("Invalid or unsupported tag length."); } - PrintAndLog("HID Prox TAG ID: %x%08x (%d) - Format Len: %dbit - FC: %d - Card: %d", - (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF, - (unsigned int) fmtLen, (unsigned int) fc, (unsigned int) cardnum); } setDemodBuf(BitStream,BitLen,idx); setClockGrid(50, waveIdx + (idx*50)); @@ -112,7 +258,7 @@ int CmdFSKdemodHID(const char *Cmd) int CmdHIDReadFSK(const char *Cmd) { int findone=0; - if(Cmd[0]=='1') findone=1; + if(Cmd[0]=='1') findone=1; UsbCommand c={CMD_HID_DEMOD_FSK}; c.arg[0]=findone; SendCommand(&c); @@ -121,30 +267,30 @@ int CmdHIDReadFSK(const char *Cmd) int CmdHIDSim(const char *Cmd) { - uint32_t hi = 0, lo = 0; - int n = 0, i = 0; - - while (sscanf(&Cmd[i++], "%1x", &n ) == 1) { - hi = (hi << 4) | (lo >> 28); - lo = (lo << 4) | (n & 0xf); - } + uint32_t hi = 0, lo = 0; + hexstring_to_int64(&hi, &lo, Cmd); + if (hi >= 0x40) { + PrintAndLog("This looks like a long tag ID. Use 'lf simfsk' for long tags. Aborting!"); + return 0; + } - PrintAndLog("Emulating tag with ID %x%08x", hi, lo); - PrintAndLog("Press pm3-button to abort simulation"); + PrintAndLog("Emulating tag with ID %x%08x", hi, lo); + PrintAndLog("Press pm3-button to abort simulation"); - UsbCommand c = {CMD_HID_SIM_TAG, {hi, lo, 0}}; - SendCommand(&c); - return 0; + UsbCommand c = {CMD_HID_SIM_TAG, {hi, lo, 0}}; + SendCommand(&c); + return 0; } int CmdHIDClone(const char *Cmd) { unsigned int hi2 = 0, hi = 0, lo = 0; - int n = 0, i = 0; UsbCommand c; if (strchr(Cmd,'l') != 0) { - while (sscanf(&Cmd[i++], "%1x", &n ) == 1) { + int n = 0, i = 0; + + while (sscanf(&Cmd[i++], "%1x", &n ) == 1) { hi2 = (hi2 << 4) | (hi >> 28); hi = (hi << 4) | (lo >> 28); lo = (lo << 4) | (n & 0xf); @@ -155,9 +301,10 @@ int CmdHIDClone(const char *Cmd) c.d.asBytes[0] = 1; } else { - while (sscanf(&Cmd[i++], "%1x", &n ) == 1) { - hi = (hi << 4) | (lo >> 28); - lo = (lo << 4) | (n & 0xf); + hexstring_to_int64(&hi, &lo, Cmd); + if (hi >= 0x40) { + PrintAndLog("This looks like a long tag ID. Aborting!"); + return 0; } PrintAndLog("Cloning tag with ID %x%08x", hi, lo); @@ -175,6 +322,73 @@ int CmdHIDClone(const char *Cmd) return 0; } + +int CmdHIDPack(const char *Cmd) { + uint32_t hi = 0, lo = 0; + short_hid_info card_info; + + if (strlen(Cmd)<3) { + PrintAndLog("Usage: lf hid pack "); + PrintAndLog(" sample: lf hid pack 26 123 4567"); + return 0; + } + + card_info.fmtLen = param_get8(Cmd, 0); + card_info.fc = param_get32ex(Cmd, 1, 0, 10); + card_info.cardnum = param_get32ex(Cmd, 2, 0, 10); + card_info.parityValid = true; + + // TODO + if (card_info.fmtLen != 26) { + PrintAndLog("Warning: Parity bits are only calculated for 26 bit IDs -- this may be invalid!"); + } + + bool ret = pack_short_hid(&hi, &lo, &card_info); + + if (ret) { + PrintAndLog("HID Prox TAG ID: %x%08x (%d) - Format Len: %u bits - FC: %u - Card: %u", + (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF, + card_info.fmtLen, card_info.fc, card_info.cardnum); + } else { + PrintAndLog("Invalid or unsupported tag length."); + } + return 0; +} + + +int CmdHIDUnpack(const char *Cmd) +{ + uint32_t hi = 0, lo = 0; + if (strlen(Cmd)<1) { + PrintAndLog("Usage: lf hid unpack "); + PrintAndLog(" sample: lf hid unpack 2006f623ae"); + return 0; + } + + hexstring_to_int64(&hi, &lo, Cmd); + if (hi >= 0x40) { + PrintAndLog("This looks like a long tag ID. Aborting!"); + return 0; + } + + short_hid_info card_info; + bool ret = unpack_short_hid(&card_info, hi, lo); + + PrintAndLog("HID Prox TAG ID: %x%08x (%d) - Format Len: %u bits - FC: %u - Card: %u", + (unsigned int) hi, (unsigned int) lo, (unsigned int) (lo>>1) & 0xFFFF, + card_info.fmtLen, card_info.fc, card_info.cardnum); + + if (card_info.fmtLen == 26) { + PrintAndLog("Parity: %s", card_info.parityValid ? "valid" : "invalid"); + } + + if (!ret) { + PrintAndLog("Invalid or unsupported tag length."); + } + return 0; +} + + static command_t CommandTable[] = { {"help", CmdHelp, 1, "This help"}, @@ -182,6 +396,8 @@ static command_t CommandTable[] = {"read", CmdHIDReadFSK, 0, "['1'] Realtime HID FSK Read from antenna (option '1' for one tag only)"}, {"sim", CmdHIDSim, 0, " -- HID tag simulator"}, {"clone", CmdHIDClone, 0, " ['l'] -- Clone HID to T55x7 (tag must be in antenna)(option 'l' for 84bit ID)"}, + {"pack", CmdHIDPack, 1, " -- packs a <38 bit (short) HID ID from its length, facility code and card number"}, + {"unpack", CmdHIDUnpack, 1, " -- unpacks a <38 bit (short) HID ID to its length, facility code and card number"}, {NULL, NULL, 0, NULL} }; diff --git a/client/cmdlfhid.h b/client/cmdlfhid.h index b03f7041..e53a95c6 100644 --- a/client/cmdlfhid.h +++ b/client/cmdlfhid.h @@ -11,10 +11,39 @@ #ifndef CMDLFHID_H__ #define CMDLFHID_H__ +#include +#include + +// Structure for unpacked "short" (<38 bits) HID Prox tags. +typedef struct { + // Format length, in bits. + uint8_t fmtLen; + + // Facility code. + uint32_t fc; + + // Card number. + uint32_t cardnum; + + // Parity validity. + // + // When used with pack_short_hid, this determines if we should calculate + // parity values for the ID. + // + // When used with unpack_short_hid, this indicates if we got valid parity + // values for the ID. + bool parityValid; +} short_hid_info; + +bool pack_short_hid(/* out */ uint32_t *hi, /* out */ uint32_t *lo, /* in */ const short_hid_info *info); +bool unpack_short_hid(short_hid_info* out, uint32_t hi, uint32_t lo); + int CmdLFHID(const char *Cmd); int CmdFSKdemodHID(const char *Cmd); int CmdHIDReadDemod(const char *Cmd); int CmdHIDSim(const char *Cmd); int CmdHIDClone(const char *Cmd); +int CmdHIDPack(const char *Cmd); +int CmdHIDUnpack(const char *Cmd); #endif -- 2.39.2