//-----------------------------------------------------------------------------
// Copyright (C) 2012 Chalk <chalk.secu at gmail.com>
// 2015 Dake <thomas.cayrou at gmail.com>
+// 2018 sguerrini97 <sguerrini97 at gmail.com>
// This code is licensed to you under the terms of the GNU GPL, version 2 or,
// at your option, any later version. See the LICENSE.txt file for the text of
struct pcf7931_config configPcf = {
{0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF},
PCF7931_DEFAULT_INITDELAY,
- PCF7931_DEFAULT_OFFSET_WIDTH,
+ PCF7931_DEFAULT_OFFSET_WIDTH,
PCF7931_DEFAULT_OFFSET_POSITION
};
int pcf7931_resetConfig(){
memset(configPcf.Pwd, 0xFF, sizeof(configPcf.Pwd) );
configPcf.InitDelay = PCF7931_DEFAULT_INITDELAY;
- configPcf.OffsetWidth = PCF7931_DEFAULT_OFFSET_WIDTH;
- configPcf.OffsetPosition = PCF7931_DEFAULT_OFFSET_POSITION;
+ configPcf.OffsetWidth = PCF7931_DEFAULT_OFFSET_WIDTH;
+ configPcf.OffsetPosition = PCF7931_DEFAULT_OFFSET_POSITION;
return 0;
}
return 0;
}
+int usage_pcf7931_bruteforce()
+{
+ PrintAndLog("Usage: lf pcf7931 bruteforce [h] <start password> <tries>");
+ PrintAndLog("This command tries to disable PAC of a PCF7931 transponder by bruteforcing the password.");
+ PrintAndLog("!! THIS IS NOT INTENDED TO RECOVER THE FULL PASSWORD !!");
+ PrintAndLog("!! DO NOT USE UNLESS THE FIRST 5 BYTES OF THE PASSWORD ARE KNOWN !!");
+ PrintAndLog("Options:");
+ PrintAndLog(" h This help");
+ PrintAndLog(" start password hex password to start from");
+ PrintAndLog(" tries How many times to send the same data frame");
+ PrintAndLog("Examples:");
+ PrintAndLog(" lf pcf7931 bruteforce 00000000123456 3");
+ return 0;
+}
+
int usage_pcf7931_config(){
PrintAndLog("Usage: lf pcf7931 config [h] [r] <pwd> <delay> <offset width> <offset position>");
PrintAndLog("This command tries to set the configuration used with PCF7931 commands");
PrintAndLog(" pwd Password, hex, 7bytes, LSB-order");
PrintAndLog(" delay Tag initialization delay (in us) decimal");
PrintAndLog(" offset Low pulses width (in us) decimal");
- PrintAndLog(" offset Low pulses position (in us) decimal");
+ PrintAndLog(" offset Low pulses position (in us) decimal");
PrintAndLog("Examples:");
PrintAndLog(" lf pcf7931 config");
PrintAndLog(" lf pcf7931 config r");
return 0;
}
-int CmdLFPCF7931Read(const char *Cmd){
+int CmdLFPCF7931Read(const char *Cmd){
uint8_t ctmp = param_getchar(Cmd, 0);
if ( ctmp == 'H' || ctmp == 'h' ) return usage_pcf7931_read();
return 0;
}
-int CmdLFPCF7931Config(const char *Cmd){
+int CmdLFPCF7931Config(const char *Cmd){
uint8_t ctmp = param_getchar(Cmd, 0);
if ( ctmp == 0) return pcf7931_printConfig();
if ( ctmp == 'H' || ctmp == 'h' ) return usage_pcf7931_config();
- if ( ctmp == 'R' || ctmp == 'r' ) return pcf7931_resetConfig();
+ if ( ctmp == 'R' || ctmp == 'r' ) return pcf7931_resetConfig();
if ( param_gethex(Cmd, 0, configPcf.Pwd, 14) ) return usage_pcf7931_config();
int CmdLFPCF7931Write(const char *Cmd){
uint8_t ctmp = param_getchar(Cmd, 0);
- if (strlen(Cmd) < 1 || ctmp == 'h' || ctmp == 'H') return usage_pcf7931_write();
+ if (strlen(Cmd) < 1 || ctmp == 'h' || ctmp == 'H') return usage_pcf7931_write();
uint8_t block = 0, bytepos = 0, data = 0;
-
+
if ( param_getdec(Cmd, 0, &block) ) return usage_pcf7931_write();
if ( param_getdec(Cmd, 1, &bytepos) ) return usage_pcf7931_write();
-
+
if ( (block > 7) || (bytepos > 15) ) return usage_pcf7931_write();
data = param_get8ex(Cmd, 2, 0, 16);
-
+
PrintAndLog("Writing block: %d", block);
PrintAndLog(" pos: %d", bytepos);
PrintAndLog(" data: 0x%02X", data);
return 0;
}
-static command_t CommandTable[] =
+int CmdLFPCF7931BruteForce(const char *Cmd){
+
+ uint8_t ctmp = param_getchar(Cmd, 0);
+ if (strlen(Cmd) < 1 || ctmp == 'h' || ctmp == 'H') return usage_pcf7931_bruteforce();
+
+ uint8_t start_password[7] = {0};
+ uint8_t tries = 3;
+
+ if (param_gethex(Cmd, 0, start_password, 14)) return usage_pcf7931_bruteforce();
+ if (param_getdec(Cmd, 1, &tries)) return usage_pcf7931_bruteforce();
+
+ PrintAndLog("Bruteforcing from password: %02x %02x %02x %02x %02x %02x %02x",
+ start_password[0],
+ start_password[1],
+ start_password[2],
+ start_password[3],
+ start_password[4],
+ start_password[5],
+ start_password[6]);
+
+ PrintAndLog("Trying each password %d times", tries);
+
+ UsbCommand c = {CMD_PCF7931_BRUTEFORCE, {bytes_to_num(start_password, 7), tries} };
+
+ c.d.asDwords[7] = (configPcf.OffsetWidth + 128);
+ c.d.asDwords[8] = (configPcf.OffsetPosition + 128);
+ c.d.asDwords[9] = configPcf.InitDelay;
+
+ clearCommandBuffer();
+ SendCommand(&c);
+ //no ack?
+ return 0;
+}
+
+static command_t CommandTable[] =
{
{"help", CmdHelp, 1, "This help"},
{"read", CmdLFPCF7931Read, 0, "Read content of a PCF7931 transponder"},
{"write", CmdLFPCF7931Write, 0, "Write data on a PCF7931 transponder."},
{"config", CmdLFPCF7931Config, 1, "Configure the password, the tags initialization delay and time offsets (optional)"},
+ {"bruteforce", CmdLFPCF7931BruteForce, 0, "Bruteforce a PCF7931 transponder password."},
{NULL, NULL, 0, NULL}
};