proxmark3/client/cmdanalyse.c

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//-----------------------------------------------------------------------------
// Copyright (C) 2016 iceman
//
// 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
// the license.
//-----------------------------------------------------------------------------
// Analyse bytes commands
//-----------------------------------------------------------------------------
#include "cmdanalyse.h"
#include "nonce2key/nonce2key.h"
static int CmdHelp(const char *Cmd);
int usage_analyse_lcr(void) {
PrintAndLog("Specifying the bytes of a UID with a known LRC will find the last byte value");
PrintAndLog("needed to generate that LRC with a rolling XOR. All bytes should be specified in HEX.");
PrintAndLog("");
PrintAndLog("Usage: analyse lcr [h] <bytes>");
PrintAndLog("Options:");
PrintAndLog(" h This help");
PrintAndLog(" <bytes> bytes to calc missing XOR in a LCR");
PrintAndLog("");
PrintAndLog("Samples:");
PrintAndLog(" analyse lcr 04008064BA");
PrintAndLog("expected output: Target (BA) requires final LRC XOR byte value: 5A");
return 0;
}
int usage_analyse_checksum(void) {
PrintAndLog("The bytes will be added with eachother and than limited with the applied mask");
PrintAndLog("Finally compute ones' complement of the least significant bytes");
PrintAndLog("");
2017-02-28 21:09:10 +08:00
PrintAndLog("Usage: analyse chksum [h] [v] b <bytes> m <mask>");
PrintAndLog("Options:");
PrintAndLog(" h This help");
2017-02-28 21:09:10 +08:00
PrintAndLog(" v supress header");
PrintAndLog(" b <bytes> bytes to calc missing XOR in a LCR");
PrintAndLog(" m <mask> bit mask to limit the outpuyt");
PrintAndLog("");
PrintAndLog("Samples:");
PrintAndLog(" analyse chksum b 137AF00A0A0D m FF");
PrintAndLog("expected output: 0x61");
return 0;
}
int usage_analyse_crc(void){
PrintAndLog("A stub method to test different crc implementations inside the PM3 sourcecode. Just because you figured out the poly, doesn't mean you get the desired output");
PrintAndLog("");
PrintAndLog("Usage: analyse crc [h] <bytes>");
PrintAndLog("Options:");
PrintAndLog(" h This help");
PrintAndLog(" <bytes> bytes to calc crc");
PrintAndLog("");
PrintAndLog("Samples:");
PrintAndLog(" analyse crc 137AF00A0A0D");
return 0;
}
int usage_analyse_hid(void){
PrintAndLog("Permute function from 'heart of darkness' paper.");
PrintAndLog("");
PrintAndLog("Usage: analyse hid [h] <r|f> <bytes>");
PrintAndLog("Options:");
PrintAndLog(" h This help");
PrintAndLog(" r reverse permuted key");
PrintAndLog(" f permute key");
PrintAndLog(" <bytes> input bytes");
PrintAndLog("");
PrintAndLog("Samples:");
PrintAndLog(" analyse hid r 0123456789abcdef");
return 0;
}
int usage_analyse_nuid(void){
PrintAndLog("Generate 4byte NUID from 7byte UID");
PrintAndLog("");
PrintAndLog("Usage: analyse hid [h] <bytes>");
PrintAndLog("Options:");
PrintAndLog(" h This help");
PrintAndLog(" <bytes> input bytes (14 hexsymbols)");
PrintAndLog("");
PrintAndLog("Samples:");
PrintAndLog(" analyse nuid 11223344556677");
return 0;
}
static uint8_t calculateLRC( uint8_t* bytes, uint8_t len) {
uint8_t LRC = 0;
for (uint8_t i = 0; i < len; i++)
LRC ^= bytes[i];
return LRC;
}
static uint16_t calcSumCrumbAdd( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++) {
sum += CRUMB(bytes[i], 0);
sum += CRUMB(bytes[i], 2);
sum += CRUMB(bytes[i], 4);
sum += CRUMB(bytes[i], 6);
}
sum &= mask;
return sum;
}
static uint16_t calcSumCrumbAddOnes( uint8_t* bytes, uint8_t len, uint32_t mask) {
return (~calcSumCrumbAdd(bytes, len, mask) & mask);
}
static uint16_t calcSumNibbleAdd( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++) {
sum += NIBBLE_LOW(bytes[i]);
sum += NIBBLE_HIGH(bytes[i]);
}
sum &= mask;
return sum;
}
static uint16_t calcSumNibbleAddOnes( uint8_t* bytes, uint8_t len, uint32_t mask){
return (~calcSumNibbleAdd(bytes, len, mask) & mask);
}
static uint16_t calcSumCrumbXor( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++) {
sum ^= CRUMB(bytes[i], 0);
sum ^= CRUMB(bytes[i], 2);
sum ^= CRUMB(bytes[i], 4);
sum ^= CRUMB(bytes[i], 6);
}
sum &= mask;
return sum;
}
static uint16_t calcSumNibbleXor( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++) {
sum ^= NIBBLE_LOW(bytes[i]);
sum ^= NIBBLE_HIGH(bytes[i]);
}
sum &= mask;
return sum;
}
static uint16_t calcSumByteXor( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++)
sum ^= bytes[i];
sum &= mask;
return sum;
}
static uint16_t calcSumByteAdd( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++)
sum += bytes[i];
sum &= mask;
return sum;
}
// Ones complement
static uint16_t calcSumByteAddOnes( uint8_t* bytes, uint8_t len, uint32_t mask) {
return (~calcSumByteAdd(bytes, len, mask) & mask);
}
static uint16_t calcSumByteSub( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++)
sum -= bytes[i];
sum &= mask;
return sum;
}
static uint16_t calcSumByteSubOnes( uint8_t* bytes, uint8_t len, uint32_t mask){
return (~calcSumByteSub(bytes, len, mask) & mask);
}
static uint16_t calcSumNibbleSub( uint8_t* bytes, uint8_t len, uint32_t mask) {
uint8_t sum = 0;
for (uint8_t i = 0; i < len; i++) {
sum -= NIBBLE_LOW(bytes[i]);
sum -= NIBBLE_HIGH(bytes[i]);
}
sum &= mask;
return sum;
}
static uint16_t calcSumNibbleSubOnes( uint8_t* bytes, uint8_t len, uint32_t mask) {
return (~calcSumNibbleSub(bytes, len, mask) & mask);
}
// BSD shift checksum 8bit version
static uint16_t calcBSDchecksum8( uint8_t* bytes, uint8_t len, uint32_t mask){
uint16_t sum = 0;
for(uint8_t i = 0; i < len; i++){
sum = ((sum & 0xFF) >> 1) | ((sum & 0x1) << 7); // rotate accumulator
sum += bytes[i]; // add next byte
sum &= 0xFF; //
}
sum &= mask;
return sum;
}
// BSD shift checksum 4bit version
static uint16_t calcBSDchecksum4( uint8_t* bytes, uint8_t len, uint32_t mask){
uint16_t sum = 0;
for(uint8_t i = 0; i < len; i++){
sum = ((sum & 0xF) >> 1) | ((sum & 0x1) << 3); // rotate accumulator
sum += NIBBLE_HIGH(bytes[i]); // add high nibble
sum &= 0xF; //
sum = ((sum & 0xF) >> 1) | ((sum & 0x1) << 3); // rotate accumulator
sum += NIBBLE_LOW(bytes[i]); // add low nibble
sum &= 0xF; //
}
sum &= mask;
return sum;
}
// measuring LFSR maximum length
int CmdAnalyseLfsr(const char *Cmd){
uint16_t start_state = 0; /* Any nonzero start state will work. */
uint16_t lfsr = start_state;
//uint32_t period = 0;
uint8_t iv = param_get8ex(Cmd, 0, 0, 16);
uint8_t find = param_get8ex(Cmd, 1, 0, 16);
printf("LEGIC LFSR IV 0x%02X: \n", iv);
printf(" bit# | lfsr | ^0x40 | 0x%02X ^ lfsr \n",find);
for (uint8_t i = 0x01; i < 0x30; i += 1) {
//period = 0;
legic_prng_init(iv);
legic_prng_forward(i);
lfsr = legic_prng_get_bits(12);
printf(" %02X | %03X | %03X | %03X \n",i, lfsr, 0x40 ^ lfsr, find ^ lfsr);
}
return 0;
}
int CmdAnalyseLCR(const char *Cmd) {
uint8_t data[50];
char cmdp = param_getchar(Cmd, 0);
if (strlen(Cmd) == 0|| cmdp == 'h' || cmdp == 'H') return usage_analyse_lcr();
int len = 0;
param_gethex_ex(Cmd, 0, data, &len);
if ( len%2 ) return usage_analyse_lcr();
len >>= 1;
uint8_t finalXor = calculateLRC(data, len);
PrintAndLog("Target [%02X] requires final LRC XOR byte value: 0x%02X",data[len-1] ,finalXor);
return 0;
}
int CmdAnalyseCRC(const char *Cmd) {
char cmdp = param_getchar(Cmd, 0);
if (strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') return usage_analyse_crc();
int len = strlen(Cmd);
if ( len & 1 ) return usage_analyse_crc();
// add 1 for null terminator.
uint8_t *data = malloc(len+1);
if ( data == NULL ) return 1;
if ( param_gethex(Cmd, 0, data, len)) {
free(data);
return usage_analyse_crc();
}
len >>= 1;
//PrintAndLog("\nTests with '%s' hex bytes", sprint_hex(data, len));
PrintAndLog("\nTests of reflection. Two current methods in source code");
PrintAndLog(" reflect(0x3e23L,3) is %04X == 0x3e26", reflect(0x3e23L,3) );
PrintAndLog(" SwapBits(0x3e23L,3) is %04X == 0x3e26", SwapBits(0x3e23L,3) );
PrintAndLog(" 0xB400 == %04X", reflect( (1 << 16 | 0xb400),16) );
//
// Test of CRC16, '123456789' string.
//
PrintAndLog("\nTests with '123456789' string");
uint8_t dataStr[] = { 0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39 };
uint8_t legic8 = CRC8Legic(dataStr, sizeof(dataStr));
PrintAndLog("LEGIC: CRC16: %X", CRC16Legic(dataStr, sizeof(dataStr), legic8));
//these below has been tested OK.
PrintAndLog("Confirmed CRC Implementations");
PrintAndLog("LEGIC: CRC8 : %X (0xC6 expected)", legic8);
PrintAndLog("MAXIM: CRC8 : %X (0xA1 expected)", CRC8Maxim(dataStr, sizeof(dataStr)));
PrintAndLog("DNP : CRC16: %X (0x82EA expected)", CRC16_DNP(dataStr, sizeof(dataStr)));
PrintAndLog("CCITT: CRC16: %X (0xE5CC expected)", CRC16_CCITT(dataStr, sizeof(dataStr)));
PrintAndLog("ICLASS org: CRC16: %X (0x expected)",iclass_crc16( (char*)dataStr, sizeof(dataStr)));
PrintAndLog("ICLASS ice: CRC16: %X (0x expected)",CRC16_ICLASS(dataStr, sizeof(dataStr)));
uint8_t dataStr1234[] = { 0x1,0x2,0x3,0x4};
PrintAndLog("ISO15693 org: : CRC16: %X (0xF0B8 expected)", Iso15693Crc(dataStr1234, sizeof(dataStr1234)));
PrintAndLog("ISO15693 ice: : CRC16: %X (0xF0B8 expected)", CRC16_Iso15693(dataStr1234, sizeof(dataStr1234)));
free(data);
return 0;
}
int CmdAnalyseCHKSUM(const char *Cmd){
uint8_t data[50];
uint8_t cmdp = 0;
uint32_t mask = 0xFFFF;
bool errors = false;
bool useHeader = false;
int len = 0;
memset(data, 0x0, sizeof(data));
while(param_getchar(Cmd, cmdp) != 0x00) {
switch(param_getchar(Cmd, cmdp)) {
case 'b':
case 'B':
param_gethex_ex(Cmd, cmdp+1, data, &len);
if ( len%2 ) errors = true;
len >>= 1;
cmdp += 2;
break;
case 'm':
case 'M':
mask = param_get32ex(Cmd, cmdp+1, 0, 16);
cmdp += 2;
break;
case 'v':
case 'V':
useHeader = true;
cmdp++;
break;
case 'h':
case 'H':
return usage_analyse_checksum();
default:
PrintAndLog("Unknown parameter '%c'", param_getchar(Cmd, cmdp));
errors = true;
break;
}
if(errors) break;
}
//Validations
if(errors) return usage_analyse_checksum();
if (useHeader) {
PrintAndLog(" add | sub | add 1's compl | sub 1's compl | xor");
PrintAndLog("byte nibble crumb | byte nibble | byte nibble cumb | byte nibble | byte nibble cumb | BSD |");
PrintAndLog("------------------+-------------+------------------+-----------------+--------------------");
}
PrintAndLog("0x%X 0x%X 0x%X | 0x%X 0x%X | 0x%X 0x%X 0x%X | 0x%X 0x%X | 0x%X 0x%X 0x%X | 0x%X 0x%X |\n",
calcSumByteAdd(data, len, mask)
, calcSumNibbleAdd(data, len, mask)
, calcSumCrumbAdd(data, len, mask)
, calcSumByteSub(data, len, mask)
, calcSumNibbleSub(data, len, mask)
, calcSumByteAddOnes(data, len, mask)
, calcSumNibbleAddOnes(data, len, mask)
, calcSumCrumbAddOnes(data, len, mask)
, calcSumByteSubOnes(data, len, mask)
, calcSumNibbleSubOnes(data, len, mask)
, calcSumByteXor(data, len, mask)
, calcSumNibbleXor(data, len, mask)
, calcSumCrumbXor(data, len, mask)
, calcBSDchecksum8(data, len, mask)
, calcBSDchecksum4(data, len, mask)
);
return 0;
}
int CmdAnalyseDates(const char *Cmd){
// look for datestamps in a given array of bytes
PrintAndLog("To be implemented. Feel free to contribute!");
return 0;
}
int CmdAnalyseTEASelfTest(const char *Cmd){
uint8_t v[8], v_le[8];
memset(v, 0x00, sizeof(v));
memset(v_le, 0x00, sizeof(v_le));
uint8_t* v_ptr = v_le;
uint8_t cmdlen = strlen(Cmd);
cmdlen = ( sizeof(v)<<2 < cmdlen ) ? sizeof(v)<<2 : cmdlen;
if ( param_gethex(Cmd, 0, v, cmdlen) > 0 ){
PrintAndLog("can't read hex chars, uneven? :: %u", cmdlen);
return 1;
}
SwapEndian64ex(v , 8, 4, v_ptr);
// ENCRYPTION KEY:
uint8_t key[16] = {0x55,0xFE,0xF6,0x30,0x62,0xBF,0x0B,0xC1,0xC9,0xB3,0x7C,0x34,0x97,0x3E,0x29,0xFB };
uint8_t keyle[16];
uint8_t* key_ptr = keyle;
SwapEndian64ex(key , sizeof(key), 4, key_ptr);
PrintAndLog("TEST LE enc| %s", sprint_hex(v_ptr, 8));
tea_decrypt(v_ptr, key_ptr);
PrintAndLog("TEST LE dec | %s", sprint_hex_ascii(v_ptr, 8));
tea_encrypt(v_ptr, key_ptr);
tea_encrypt(v_ptr, key_ptr);
PrintAndLog("TEST enc2 | %s", sprint_hex_ascii(v_ptr, 8));
return 0;
}
int CmdAnalyseA(const char *Cmd){
/*
piwi
// uid(2e086b1a) nt(230736f6) ks(0b0008000804000e) nr(000000000)
// uid(2e086b1a) nt(230736f6) ks(0e0b0e0b090c0d02) nr(000000001)
// uid(2e086b1a) nt(230736f6) ks(0e05060e01080b08) nr(000000002)
uint64_t d1[] = {0x2e086b1a, 0x230736f6, 0x0000001, 0x0e0b0e0b090c0d02};
uint64_t d2[] = {0x2e086b1a, 0x230736f6, 0x0000002, 0x0e05060e01080b08};
// uid(17758822) nt(c0c69e59) ks(080105020705040e) nr(00000001)
// uid(17758822) nt(c0c69e59) ks(01070a05050c0705) nr(00000002)
uint64_t d1[] = {0x17758822, 0xc0c69e59, 0x0000001, 0x080105020705040e};
uint64_t d2[] = {0x17758822, 0xc0c69e59, 0x0000002, 0x01070a05050c0705};
// uid(6e442129) nt(8f699195) ks(090d0b0305020f02) nr(00000001)
// uid(6e442129) nt(8f699195) ks(03030508030b0c0e) nr(00000002)
// uid(6e442129) nt(8f699195) ks(02010f030c0d050d) nr(00000003)
// uid(6e442129) nt(8f699195) ks(00040f0f0305030e) nr(00000004)
uint64_t d1[] = {0x6e442129, 0x8f699195, 0x0000001, 0x090d0b0305020f02};
uint64_t d2[] = {0x6e442129, 0x8f699195, 0x0000004, 0x00040f0f0305030e};
uid(3e172b29) nt(039b7bd2) ks(0c0e0f0505080800) nr(00000001)
uid(3e172b29) nt(039b7bd2) ks(0e06090d03000b0f) nr(00000002)
*/
uint64_t key = 0;
uint64_t d1[] = {0x3e172b29, 0x039b7bd2, 0x0000001, 0x0c0e0f0505080800};
uint64_t d2[] = {0x3e172b29, 0x039b7bd2, 0x0000002, 0x0e06090d03000b0f};
nonce2key_ex(0, 0 , d1[0], d1[1], d1[2], d1[3], &key);
nonce2key_ex(0, 0 , d2[0], d2[1], d2[2], d2[3], &key);
return 0;
}
static void permute(uint8_t *data, uint8_t len, uint8_t *output){
#define KEY_SIZE 8
if ( len > KEY_SIZE ) {
for(uint8_t m = 0; m < len; m += KEY_SIZE){
permute(data+m, KEY_SIZE, output+m);
}
return;
}
if ( len != KEY_SIZE ) {
printf("wrong key size\n");
return;
}
uint8_t i,j,p, mask;
for( i=0; i < KEY_SIZE; ++i){
p = 0;
mask = 0x80 >> i;
for( j=0; j < KEY_SIZE; ++j){
p >>= 1;
if (data[j] & mask)
p |= 0x80;
}
output[i] = p;
}
}
static void permute_rev(uint8_t *data, uint8_t len, uint8_t *output){
permute(data, len, output);
permute(output, len, data);
permute(data, len, output);
}
static void simple_crc(uint8_t *data, uint8_t len, uint8_t *output){
uint8_t crc = 0;
for( uint8_t i=0; i < len; ++i){
// seventh byte contains the crc.
if ( (i & 0x7) == 0x7 ) {
output[i] = crc ^ 0xFF;
crc = 0;
} else {
output[i] = data[i];
crc ^= data[i];
}
}
}
// DES doesn't use the MSB.
static void shave(uint8_t *data, uint8_t len){
for (uint8_t i=0; i<len; ++i)
data[i] &= 0xFE;
}
static void generate_rev(uint8_t *data, uint8_t len) {
uint8_t *key = calloc(len,1);
printf("input permuted key | %s \n", sprint_hex(data, len));
permute_rev(data, len, key);
printf(" unpermuted key | %s \n", sprint_hex(key, len));
shave(key, len);
printf(" key | %s \n", sprint_hex(key, len));
free(key);
}
static void generate(uint8_t *data, uint8_t len) {
uint8_t *key = calloc(len,1);
uint8_t *pkey = calloc(len,1);
printf(" input key | %s \n", sprint_hex(data, len));
permute(data, len, pkey);
printf(" permuted key | %s \n", sprint_hex(pkey, len));
simple_crc(pkey, len, key );
printf(" CRC'ed key | %s \n", sprint_hex(key, len));
free(key);
free(pkey);
}
int CmdAnalyseHid(const char *Cmd){
uint8_t key[8] = {0};
uint8_t key_std_format[8] = {0};
uint8_t key_iclass_format[8] = {0};
uint8_t data[16] = {0};
bool isReverse = FALSE;
int len = 0;
char cmdp = param_getchar(Cmd, 0);
if (strlen(Cmd) == 0|| cmdp == 'h' || cmdp == 'H') return usage_analyse_hid();
if ( cmdp == 'r' || cmdp == 'R' )
isReverse = TRUE;
param_gethex_ex(Cmd, 1, data, &len);
if ( len%2 ) return usage_analyse_hid();
len >>= 1;
memcpy(key, data, 8);
if ( isReverse ) {
generate_rev(data, len);
permutekey_rev(key, key_std_format);
printf(" holiman iclass key | %s \n", sprint_hex(key_std_format, 8));
}
else {
generate(data, len);
permutekey(key, key_iclass_format);
printf(" holiman std key | %s \n", sprint_hex(key_iclass_format, 8));
}
return 0;
}
void generate4bNUID(uint8_t *uid, uint8_t *nuid){
uint16_t crc;
uint8_t first, second;
ComputeCrc14443(CRC_14443_A, uid, 3, &first, &second);
nuid[0] |= (second & 0xE0) | 0xF;
nuid[1] = first;
crc = first;
crc |= second << 8;
UpdateCrc14443(uid[3], &crc);
UpdateCrc14443(uid[4], &crc);
UpdateCrc14443(uid[5], &crc);
UpdateCrc14443(uid[6], &crc);
nuid[2] = (crc >> 8) & 0xFF ;
nuid[3] = crc & 0xFF;
}
int CmdAnalyseNuid(const char *Cmd){
uint8_t nuid[4] = {0};
uint8_t uid[7] = {0};
int len = 0;
char cmdp = param_getchar(Cmd, 0);
if (strlen(Cmd) == 0|| cmdp == 'h' || cmdp == 'H') return usage_analyse_nuid();
/* selftest UID 040D681AB52281 -> NUID 8F430FEF */
if (cmdp == 't' || cmdp == 'T') {
memcpy(uid, "\x04\x0d\x68\x1a\xb5\x22\x81", 7);
generate4bNUID(uid, nuid);
if ( 0 == memcmp(nuid, "\x8f\x43\x0f\xef", 4))
printf("Selftest OK\n");
else
printf("Selftest Failed\n");
return 0;
}
param_gethex_ex(Cmd, 0, uid, &len);
if ( len%2 || len != 14) return usage_analyse_nuid();
generate4bNUID(uid, nuid);
printf("UID | %s \n", sprint_hex(uid, 7));
printf("NUID | %s \n", sprint_hex(nuid, 4));
return 0;
}
static command_t CommandTable[] = {
{"help", CmdHelp, 1, "This help"},
{"lcr", CmdAnalyseLCR, 1, "Generate final byte for XOR LRC"},
{"crc", CmdAnalyseCRC, 1, "Stub method for CRC evaluations"},
{"chksum", CmdAnalyseCHKSUM, 1, "Checksum with adding, masking and one's complement"},
{"dates", CmdAnalyseDates, 1, "Look for datestamps in a given array of bytes"},
{"tea", CmdAnalyseTEASelfTest, 1, "Crypto TEA test"},
{"lfsr", CmdAnalyseLfsr, 1, "LFSR tests"},
{"a", CmdAnalyseA, 1, "num bits test"},
{"hid", CmdAnalyseHid, 1, "Permute function from 'heart of darkness' paper"},
{"nuid", CmdAnalyseNuid, 1, "create NUID from 7byte UID"},
{NULL, NULL, 0, NULL}
};
int CmdAnalyse(const char *Cmd) {
clearCommandBuffer();
CmdsParse(CommandTable, Cmd);
return 0;
}
int CmdHelp(const char *Cmd) {
CmdsHelp(CommandTable);
return 0;
}