From 6a21c780fa652f338c0755ee44b3c465f44a43ba Mon Sep 17 00:00:00 2001 From: iceman1001 Date: Mon, 16 Dec 2019 13:51:10 +0100 Subject: [PATCH] chg: lf gallagher demod - using the research from Matt, @megabug, to get better support. WIP. --- client/cmdlfgallagher.c | 77 +++++++++++++++++++++++++++++++++-------- 1 file changed, 63 insertions(+), 14 deletions(-) diff --git a/client/cmdlfgallagher.c b/client/cmdlfgallagher.c index 9704afc60..4752343d5 100644 --- a/client/cmdlfgallagher.c +++ b/client/cmdlfgallagher.c @@ -12,7 +12,7 @@ #include "cmdlfgallagher.h" #include //tolower - +#include #include "commonutil.h" // ARRAYLEN #include "common.h" #include "cmdparser.h" // command_t @@ -23,6 +23,7 @@ #include "lfdemod.h" // preamble test #include "protocols.h" // t55xx defines #include "cmdlft55xx.h" // clone.. +#include "crc.h" // CRC8/Cardx static int CmdHelp(const char *Cmd); @@ -39,6 +40,32 @@ static int usage_lf_gallagher_clone(void) { return PM3_SUCCESS; } +static void descramble( uint8_t *arr, uint8_t len) { + + uint8_t lut[] = { + 0xa3, 0xb0, 0x80, 0xc6, 0xb2, 0xf4, 0x5c, 0x6c, 0x81, 0xf1, 0xbb, 0xeb, 0x55, 0x67, 0x3c, 0x05, + 0x1a, 0x0e, 0x61, 0xf6, 0x22, 0xce, 0xaa, 0x8f, 0xbd, 0x3b, 0x1f, 0x5e, 0x44, 0x04, 0x51, 0x2e, + 0x4d, 0x9a, 0x84, 0xea, 0xf8, 0x66, 0x74, 0x29, 0x7f, 0x70, 0xd8, 0x31, 0x7a, 0x6d, 0xa4, 0x00, + 0x82, 0xb9, 0x5f, 0xb4, 0x16, 0xab, 0xff, 0xc2, 0x39, 0xdc, 0x19, 0x65, 0x57, 0x7c, 0x20, 0xfa, + 0x5a, 0x49, 0x13, 0xd0, 0xfb, 0xa8, 0x91, 0x73, 0xb1, 0x33, 0x18, 0xbe, 0x21, 0x72, 0x48, 0xb6, + 0xdb, 0xa0, 0x5d, 0xcc, 0xe6, 0x17, 0x27, 0xe5, 0xd4, 0x53, 0x42, 0xf3, 0xdd, 0x7b, 0x24, 0xac, + 0x2b, 0x58, 0x1e, 0xa7, 0xe7, 0x86, 0x40, 0xd3, 0x98, 0x97, 0x71, 0xcb, 0x3a, 0x0f, 0x01, 0x9b, + 0x6e, 0x1b, 0xfc, 0x34, 0xa6, 0xda, 0x07, 0x0c, 0xae, 0x37, 0xca, 0x54, 0xfd, 0x26, 0xfe, 0x0a, + 0x45, 0xa2, 0x2a, 0xc4, 0x12, 0x0d, 0xf5, 0x4f, 0x69, 0xe0, 0x8a, 0x77, 0x60, 0x3f, 0x99, 0x95, + 0xd2, 0x38, 0x36, 0x62, 0xb7, 0x32, 0x7e, 0x79, 0xc0, 0x46, 0x93, 0x2f, 0xa5, 0xba, 0x5b, 0xaf, + 0x52, 0x1d, 0xc3, 0x75, 0xcf, 0xd6, 0x4c, 0x83, 0xe8, 0x3d, 0x30, 0x4e, 0xbc, 0x08, 0x2d, 0x09, + 0x06, 0xd9, 0x25, 0x9e, 0x89, 0xf2, 0x96, 0x88, 0xc1, 0x8c, 0x94, 0x0b, 0x28, 0xf0, 0x47, 0x63, + 0xd5, 0xb3, 0x68, 0x56, 0x9c, 0xf9, 0x6f, 0x41, 0x50, 0x85, 0x8b, 0x9d, 0x59, 0xbf, 0x9f, 0xe2, + 0x8e, 0x6a, 0x11, 0x23, 0xa1, 0xcd, 0xb5, 0x7d, 0xc7, 0xa9, 0xc8, 0xef, 0xdf, 0x02, 0xb8, 0x03, + 0x6b, 0x35, 0x3e, 0x2c, 0x76, 0xc9, 0xde, 0x1c, 0x4b, 0xd1, 0xed, 0x14, 0xc5, 0xad, 0xe9, 0x64, + 0x4a, 0xec, 0x8d, 0xf7, 0x10, 0x43, 0x78, 0x15, 0x87, 0xe4, 0xd7, 0x92, 0xe1, 0xee, 0xe3, 0x90 + }; + + for (int i = 0; i < len; i++) { + arr[i] = lut[arr[i]]; + } +} + //see ASK/MAN Demod for what args are accepted static int CmdGallagherDemod(const char *Cmd) { @@ -71,10 +98,39 @@ static int CmdGallagherDemod(const char *Cmd) { uint32_t raw2 = bytebits_to_byte(DemodBuffer + 32, 32); uint32_t raw3 = bytebits_to_byte(DemodBuffer + 64, 32); - // preamble CS? + // bytes + uint8_t arr[8] = {0}; + for(int i = 0, pos = 0; i < ARRAYLEN(arr); i++) { + pos = (i * 8) + i; + arr[i] = bytebits_to_byte(DemodBuffer + pos, 8); + printf("%d -", pos ); + } + printf("\n"); - PrintAndLogEx(SUCCESS, "GALLAGHER Tag Found -- Raw: %08X%08X%08X", raw1, raw2, raw3); - PrintAndLogEx(INFO, "How the Raw ID is translated by the reader is unknown. Share your trace file on forum"); + // crc + uint8_t crc = bytebits_to_byte(DemodBuffer + 72, 8); + uint8_t calc_crc = CRC8Cardx(arr, ARRAYLEN(arr) ); + + PrintAndLogEx(INFO, " Before: %s", sprint_hex(arr, 8)); + descramble(arr, ARRAYLEN(arr)); + PrintAndLogEx(INFO, " After : %s", sprint_hex(arr, 8)); + + // 4bit region code + uint8_t rc = (arr[3] & 0x0E) >> 1; + + // 16bit FC + uint16_t fc = (arr[5] & 0x0F) << 12 | arr[1] << 4 | ((arr[7] >> 4) & 0x0F); + + // 24bit CN + uint32_t cn = arr[0] << 16 | (arr[4] & 0x1F) << 11 | arr[2] << 3 | (arr[3] & 0xE0) >> 4; + + // 4bit issue level + uint8_t il = arr[7] & 0x0F; + + PrintAndLogEx(SUCCESS, "GALLAGHER Tag Found -- Region: %u FC: %u CN: %u Issue Level: %u", rc, fc, cn, il); + PrintAndLogEx(SUCCESS, " Printed: %C%u", rc + 0x40, fc); + PrintAndLogEx(SUCCESS, " Raw: %08X%08X%08X", raw1, raw2, raw3); + PrintAndLogEx(SUCCESS, " CRC: %02X - %02X (%s)", crc, calc_crc, (crc == calc_crc) ? "OK":"Failed"); return PM3_SUCCESS; } @@ -126,7 +182,6 @@ static int CmdGallagherClone(const char *Cmd) { } static int CmdGallagherSim(const char *Cmd) { - // ASK/MAN sim. PrintAndLogEx(INFO, " To be implemented, feel free to contribute!"); return PM3_SUCCESS; @@ -152,20 +207,14 @@ int CmdLFGallagher(const char *Cmd) { return CmdsParse(CommandTable, Cmd); } -// by marshmellow -// find PAC preamble in already demoded data +// find Gallagher preamble in already demoded data int detectGallagher(uint8_t *dest, size_t *size) { if (*size < 96) return -1; //make sure buffer has data size_t startIdx = 0; - uint8_t preamble[] = { - //0, 0, 0, 0, - 1, 1, 1, 1, - 1, 1, 1, 1, 1, 1, 0, 1, - 0, 1, 0, 1, 0, 1, 0, 0, - 0, 1, 1, 0, 0, 0 - }; + uint8_t preamble[] = { 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0 }; if (!preambleSearch(dest, preamble, sizeof(preamble), size, &startIdx)) return -2; //preamble not found + if (*size != 96) return -3; //wrong demoded size //return start position return (int)startIdx;