CHG: 'LF VISA2000 CLONE' fixed the wrong blocknum index in output. Thanks @martin...

[proxmark3-svn] / client / cmdlfvisa2000.c

diff --git a/client/cmdlfvisa2000.c b/client/cmdlfvisa2000.c
index da1fd2d118813ebd31008cf63f073df01c130da0..9148a435b05767328c6b9ed60cbf571202430c94 100644 (file)
--- a/client/cmdlfvisa2000.c
+++ b/client/cmdlfvisa2000.c
@@ -9,6 +9,8 @@
 
 #include "cmdlfvisa2000.h"
 
+#define BL0CK1 0x56495332
+
 static int CmdHelp(const char *Cmd);
 
 int usage_lf_visa2k_clone(void){
@@ -36,11 +38,18 @@ int usage_lf_visa2k_sim(void) {
        return 0;
 }
 
+static uint8_t visa_chksum( uint32_t id ) {
+    uint8_t sum = 0;
+    for (uint8_t i = 0; i < 32; i += 4)
+        sum ^=  (id >> i) & 0xF;
+    return sum & 0xF;
+}
+
 //see ASKDemod for what args are accepted
 int CmdVisa2kDemod(const char *Cmd) {
 
        //ASK / Manchester
-       bool st = true;
+       bool st = TRUE;
        if (!ASKDemod_ext("64 0 0", FALSE, FALSE, 1, &st)) {
                if (g_debugMode) PrintAndLog("DEBUG: Error - Visa2k: ASK/Manchester Demod failed");
                return 0;
@@ -67,7 +76,16 @@ int CmdVisa2kDemod(const char *Cmd) {
        uint32_t raw2 = bytebits_to_byte(DemodBuffer+32, 32);
        uint32_t raw3 = bytebits_to_byte(DemodBuffer+64, 32);
 
+       // chksum
+       uint8_t calc = visa_chksum(raw2);
+       uint8_t chk = raw3 & 0xF;       
+       // test checksums
+       if ( chk != calc ) { 
+               printf("DEBUG: error: Visa2000 checksum failed %x - %x\n", chk, calc);
+               return 0;
+       }
        PrintAndLog("Visa2000 Tag Found: Card ID %u,  Raw: %08X%08X%08X", raw2,  raw1 ,raw2, raw3);
+
        return 1;
 }
 
@@ -80,12 +98,8 @@ int CmdVisa2kRead(const char *Cmd) {
 int CmdVisa2kClone(const char *Cmd) {
 
        uint64_t id = 0;
-       uint32_t blocks[4] = {T55x7_MODULATION_MANCHESTER | T55x7_BITRATE_RF_64 | T55x7_ST_TERMINATOR |3<<T55x7_MAXBLOCK_SHIFT, 0, 0};
+       uint32_t blocks[4] = {T55x7_MODULATION_MANCHESTER | T55x7_BITRATE_RF_64 | T55x7_ST_TERMINATOR |3<<T55x7_MAXBLOCK_SHIFT, BL0CK1, 0};
 
-       // uint8_t bits[96];
-       // uint8_t *bs = bits;
-       // memset(bs, 0, sizeof(bits));
-       
        char cmdp = param_getchar(Cmd, 0);
        if (strlen(Cmd) == 0 || cmdp == 'h' || cmdp == 'H') return usage_lf_visa2k_clone();
 
@@ -97,23 +111,15 @@ int CmdVisa2kClone(const char *Cmd) {
                blocks[0] = T5555_MODULATION_MANCHESTER | 64<<T5555_BITRATE_SHIFT | T5555_ST_TERMINATOR | 3<<T5555_MAXBLOCK_SHIFT;
        }
        
-       // if ( !getJablotronBits(fullcode, bs)) {
-               // PrintAndLog("Error with tag bitstream generation.");
-               // return 1;
-       // }    
-       
        // 
-       blocks[1] = 0x56495332;
        blocks[2] = id;
-       blocks[3] = 0;
+       blocks[3] = visa_chksum( id);
 
        PrintAndLog("Preparing to clone Visa2000 to T55x7 with CardId: %u", id);
        PrintAndLog("Blk | Data ");
        PrintAndLog("----+------------");
-       PrintAndLog(" 00 | 0x%08x", blocks[0]);
-       PrintAndLog(" 01 | 0x%08x", blocks[1]);
-       PrintAndLog(" 02 | 0x%08x", blocks[2]);
-       PrintAndLog(" 02 | 0x%08x", blocks[3]);
+       for(int i = 0; i<4; ++i)
+       PrintAndLog(" %02d | 0x%08x", i , blocks[i]);
        
        UsbCommand resp;
        UsbCommand c = {CMD_T55XX_WRITE_BLOCK, {0,0,0}};
@@ -148,12 +154,12 @@ int CmdVisa2kSim(const char *Cmd) {
        PrintAndLog("Simulating Visa2000 - CardId: %u", id);
 
        UsbCommand c = {CMD_ASK_SIM_TAG, {arg1, arg2, size}};
-       
-       uint32_t blocks[3] = { 0x56495332, id, 0};
 
-       for(int i=0; i<3; ++i){
+       uint32_t blocks[3] = { BL0CK1, id,  visa_chksum(id) };
+
+       for(int i=0; i<3; ++i)
                num_to_bytebits(blocks[i], 32, c.d.asBytes + i*32);
-       }
+
        clearCommandBuffer();
        SendCommand(&c);
        return 0;