#include "cmdhflegic.h"
#include "cmdmain.h"
#include "util.h"
+#include "crc.h"
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.
* This is based on information given in the talk held
* by Henryk Ploetz and Karsten Nohl at 26c3
*/
-int CmdLegicDecode(const char *Cmd)
-{
- int i, j, k, n;
+int CmdLegicDecode(const char *Cmd) {
+ int i, k, n;
int segment_len = 0;
int segment_flag = 0;
int stamp_len = 0;
int crc = 0;
int wrp = 0;
int wrc = 0;
- uint8_t data_buf[3076]; // receiver buffer
- char out_string[3076]; // just use big buffer - bad practice
+ uint8_t data_buf[1200]; // receiver buffer
+ //char out_string[3076]; // just use big buffer - bad practice
char token_type[4];
// copy data from proxmark into buffer
WaitForResponse(CMD_ACK,NULL);
// 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("MCD: %02x, MSN: %02x %02x %02x, MCC: %02x",
+ PrintAndLog("MCD: %02x, MSN: %02x %02x %02x, MCC: %02x %s",
data_buf[0],
data_buf[1],
data_buf[2],
data_buf[3],
- data_buf[4]
+ data_buf[4],
+ (calc_crc == crc) ? "OK":"Failed"
);
-
- crc = data_buf[4];
switch (data_buf[5]&0x7f) {
case 0x00 ... 0x2f:
(data_buf[i+4]^crc)
);
- i+=5;
+ i += 5;
if ( wrc>0 ) {
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));
- out_string[j+2] = ' ';
- }
-
- out_string[j] = '\0';
-
- PrintAndLog("%s", out_string);
+
+ for ( k=i; k < wrc; k++)
+ data_buf[k] ^= crc;
+
+ for ( k=i; k < wrc; k += 8)
+ PrintAndLog("%s", sprint_hex( data_buf+k, 8) );
+
+ i += wrc;
}
if ( wrp>wrc ) {
PrintAndLog("Remaining write protected area:");
- for (k=0, j=0; k < (wrp-wrc) && j<(sizeof(out_string)-3); k++, i++, j += 3) {
- sprintf(&out_string[j], "%02x", (data_buf[i]^crc));
- out_string[j+2] = ' ';
- };
-
- 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);
+ if ( data_buf[k] > 0) {
+ for (k=i; k < (wrp-wrc); k++)
+ data_buf[k] ^= crc;
}
+
+ 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:");
- 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));
- out_string[j+2] = ' ';
- };
-
- out_string[j] = '\0';
-
- PrintAndLog("%s", out_string);
+
+ if ( data_buf[k] > 0 ) {
+ for ( k=i; k < (segment_len - wrp - 5); k++)
+ data_buf[k] ^= crc;
+ }
+
+ for ( k=i; k < (segment_len - wrp - 5); k++)
+ PrintAndLog("%s", sprint_hex( data_buf+k, 16) );
// end with last segment
if (segment_flag & 0x8) return 0;
}
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]);
clearCommandBuffer();
SendCommand(&c);
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[] = {
- {"help", CmdHelp, 1, "This help"},
- {"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"},
- {"save", CmdLegicSave, 0, "<filename> [<length>] -- Store 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)"},
- {"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"},
+ {"help", CmdHelp, 1, "This help"},
+ {"decode", CmdLegicDecode, 0, "Display deobfuscated and decoded LEGIC RF tag data (use after hf legic reader)"},
+ {"read", CmdLegicRFRead, 0, "[offset][length] -- read bytes from a LEGIC card"},
+ {"save", CmdLegicSave, 0, "<filename> [<length>] -- Store 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)"},
+ {"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"},
+ {"crc8", CmdLegicCalcCrc8, 1, "Calculate Legic CRC8 over given hexbytes"},
{NULL, NULL, 0, NULL}
};
projects / proxmark3-svn / blobdiff