RfidResearchGroup/proxmark3
1
1
Fork 0
mirror of https://github.com/RfidResearchGroup/proxmark3.git synced 2025-03-20 12:07:05 +08:00
Code Issues Projects Releases Packages Wiki Activity

ADD: Calc legic Crc8 method on given input hexstring.

Browse source
This commit is contained in:
iceman1001 2016-02-14 11:56:54 +01:00
parent 5a6e19e614
commit 3b920280db
2 changed files with 80 additions and 47 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

124
client/cmdhflegic.c
View file

@ -17,24 +17,35 @@
#include "cmdhflegic.h" #include "cmdhflegic.h"
#include "cmdmain.h" #include "cmdmain.h"
#include "util.h" #include "util.h"
#include "crc.h"
static int CmdHelp(const char *Cmd); static int CmdHelp(const char *Cmd);
int usage_legic_calccrc8(void){
PrintAndLog("Calculates the legic crc8 on the input hexbytes.");
PrintAndLog("There must be an even number of hexsymbols as input.");
PrintAndLog("Usage: hf legic crc8 <hexbytes>");
PrintAndLog("Options :");
PrintAndLog(" <hexbytes> : hex bytes in a string");
PrintAndLog("");
PrintAndLog("Sample : hf legic crc8 deadbeef1122");
return 0;
}
/* /*
* Output BigBuf and deobfuscate LEGIC RF tag data. * Output BigBuf and deobfuscate LEGIC RF tag data.
* This is based on information given in the talk held * This is based on information given in the talk held
* by Henryk Ploetz and Karsten Nohl at 26c3 * by Henryk Ploetz and Karsten Nohl at 26c3
*/ */
int CmdLegicDecode(const char *Cmd) int CmdLegicDecode(const char *Cmd) {
{ int i, k, n;
int i, j, k, n;
int segment_len = 0; int segment_len = 0;
int segment_flag = 0; int segment_flag = 0;
int stamp_len = 0; int stamp_len = 0;
int crc = 0; int crc = 0;
int wrp = 0; int wrp = 0;
int wrc = 0; int wrc = 0;
uint8_t data_buf[3076]; // receiver buffer uint8_t data_buf[1200]; // receiver buffer
char out_string[3076]; // just use big buffer - bad practice //char out_string[3076]; // just use big buffer - bad practice
char token_type[4]; char token_type[4];
// copy data from proxmark into buffer // copy data from proxmark into buffer
@ -42,18 +53,19 @@ int CmdLegicDecode(const char *Cmd)
WaitForResponse(CMD_ACK,NULL); WaitForResponse(CMD_ACK,NULL);
// Output CDF System area (9 bytes) plus remaining header area (12 bytes) // Output CDF System area (9 bytes) plus remaining header area (12 bytes)
crc = data_buf[4];
uint32_t calc_crc = CRC8Legic(data_buf, 4);
PrintAndLog("\nCDF: System Area"); PrintAndLog("\nCDF: System Area");
PrintAndLog("MCD: %02x, MSN: %02x %02x %02x, MCC: %02x", PrintAndLog("MCD: %02x, MSN: %02x %02x %02x, MCC: %02x %s",
data_buf[0], data_buf[0],
data_buf[1], data_buf[1],
data_buf[2], data_buf[2],
data_buf[3], data_buf[3],
data_buf[4] data_buf[4],
(calc_crc == crc) ? "OK":"Failed"
); );
crc = data_buf[4];
switch (data_buf[5]&0x7f) { switch (data_buf[5]&0x7f) {
case 0x00 ... 0x2f: case 0x00 ... 0x2f:
@ -116,46 +128,46 @@ int CmdLegicDecode(const char *Cmd)
(data_buf[i+4]^crc) (data_buf[i+4]^crc)
); );
i+=5; i += 5;
if ( wrc>0 ) { if ( wrc>0 ) {
PrintAndLog("WRC protected area:"); PrintAndLog("WRC protected area:");
for ( k=0, j=0; k < wrc && j<(sizeof(out_string)-3); k++, i++, j += 3) {
sprintf(&out_string[j], "%02x", (data_buf[i]^crc)); for ( k=i; k < wrc; k++)
out_string[j+2] = ' '; data_buf[k] ^= crc;
}
for ( k=i; k < wrc; k += 8)
out_string[j] = '\0'; PrintAndLog("%s", sprint_hex( data_buf+k, 8) );
PrintAndLog("%s", out_string); i += wrc;
} }
if ( wrp>wrc ) { if ( wrp>wrc ) {
PrintAndLog("Remaining write protected area:"); PrintAndLog("Remaining write protected area:");
for (k=0, j=0; k < (wrp-wrc) && j<(sizeof(out_string)-3); k++, i++, j += 3) { if ( data_buf[k] > 0) {
sprintf(&out_string[j], "%02x", (data_buf[i]^crc)); for (k=i; k < (wrp-wrc); k++)
out_string[j+2] = ' '; data_buf[k] ^= crc;
};
out_string[j] = '\0';
PrintAndLog("%s", out_string);
if( (wrp-wrc) == 8 ) {
sprintf(out_string, "Card ID: %2X%02X%02X", data_buf[i-4]^crc, data_buf[i-3]^crc, data_buf[i-2]^crc);
PrintAndLog("%s", out_string);
} }
for (k=i; k < (wrp-wrc); k++)
PrintAndLog("%s", sprint_hex( data_buf+k, 16) );
i += (wrp-wrc);
if( (wrp-wrc) == 8 )
PrintAndLog("Card ID: %2X%02X%02X", data_buf[i-4]^crc, data_buf[i-3]^crc, data_buf[i-2]^crc);
} }
PrintAndLog("Remaining segment payload:"); PrintAndLog("Remaining segment payload:");
for ( k=0, j=0; k < (segment_len - wrp - 5) && j<(sizeof(out_string)-3); k++, i++, j += 3) {
sprintf(&out_string[j], "%02x", (data_buf[i]^crc)); if ( data_buf[k] > 0 ) {
out_string[j+2] = ' '; for ( k=i; k < (segment_len - wrp - 5); k++)
}; data_buf[k] ^= crc;
}
out_string[j] = '\0';
for ( k=i; k < (segment_len - wrp - 5); k++)
PrintAndLog("%s", out_string); PrintAndLog("%s", sprint_hex( data_buf+k, 16) );
// end with last segment // end with last segment
if (segment_flag & 0x8) return 0; if (segment_flag & 0x8) return 0;
@ -282,7 +294,7 @@ int CmdLegicSave(const char *Cmd) {
} }
int CmdLegicRfSim(const char *Cmd) { int CmdLegicRfSim(const char *Cmd) {
UsbCommand c= {CMD_SIMULATE_TAG_LEGIC_RF, {6,3,0}}; UsbCommand c = {CMD_SIMULATE_TAG_LEGIC_RF, {6,3,0}};
sscanf(Cmd, " %"lli" %"lli" %"lli, &c.arg[0], &c.arg[1], &c.arg[2]); sscanf(Cmd, " %"lli" %"lli" %"lli, &c.arg[0], &c.arg[1], &c.arg[2]);
clearCommandBuffer(); clearCommandBuffer();
SendCommand(&c); SendCommand(&c);
@ -325,15 +337,33 @@ int CmdLegicRfFill(const char *Cmd) {
return 0; return 0;
} }
int CmdLegicCalcCrc8(const char *Cmd){
int len = strlen(Cmd);
if (len & 1 ) return usage_legic_calccrc8();
uint8_t *data = malloc(len);
if ( data == NULL ) return 1;
param_gethex(Cmd, 0, data, len );
uint32_t checksum = CRC8Legic(data, len/2);
PrintAndLog("Bytes: %s || CRC8: %X", sprint_hex(data, len/2), checksum );
free(data);
return 0;
}
static command_t CommandTable[] = { static command_t CommandTable[] = {
{"help", CmdHelp, 1, "This help"}, {"help", CmdHelp, 1, "This help"},
{"decode", CmdLegicDecode, 0, "Display deobfuscated and decoded LEGIC RF tag data (use after hf legic reader)"}, {"decode", CmdLegicDecode, 0, "Display deobfuscated and decoded LEGIC RF tag data (use after hf legic reader)"},
{"reader", CmdLegicRFRead, 0, "[offset [length]] -- read bytes from a LEGIC card"}, {"read", CmdLegicRFRead, 0, "[offset][length] -- read bytes from a LEGIC card"},
{"save", CmdLegicSave, 0, "<filename> [<length>] -- Store samples"}, {"save", CmdLegicSave, 0, "<filename> [<length>] -- Store samples"},
{"load", CmdLegicLoad, 0, "<filename> -- Restore samples"}, {"load", CmdLegicLoad, 0, "<filename> -- Restore samples"},
{"sim", CmdLegicRfSim, 0, "[phase drift [frame drift [req/resp drift]]] Start tag simulator (use after load or read)"}, {"sim", CmdLegicRfSim, 0, "[phase drift [frame drift [req/resp drift]]] Start tag simulator (use after load or read)"},
{"write", CmdLegicRfWrite,0, "<offset> <length> -- Write sample buffer (user after load or read)"}, {"write", CmdLegicRfWrite,0, "<offset> <length> -- Write sample buffer (user after load or read)"},
{"fill", CmdLegicRfFill, 0, "<offset> <length> <value> -- Fill/Write tag with constant value"}, {"fill", CmdLegicRfFill, 0, "<offset> <length> <value> -- Fill/Write tag with constant value"},
{"crc8", CmdLegicCalcCrc8, 1, "Calculate Legic CRC8 over given hexbytes"},
{NULL, NULL, 0, NULL} {NULL, NULL, 0, NULL}
}; };

3
client/cmdhflegic.h
View file

@ -21,4 +21,7 @@ int CmdLegicRfSim(const char *Cmd);
int CmdLegicRfWrite(const char *Cmd); int CmdLegicRfWrite(const char *Cmd);
int CmdLegicRfFill(const char *Cmd); int CmdLegicRfFill(const char *Cmd);
int CmdLegicCalcCrc8(const char *Cmd);
int usage_legic_calccrc8(void);
#endif #endif