CHG: minor LF adjustments.

[proxmark3-svn] / client / cmdlfvisa2000.c

diff --git a/client/cmdlfvisa2000.c b/client/cmdlfvisa2000.c
index da1fd2d118813ebd31008cf63f073df01c130da0..5c030ec3b83c18570404553391e58910ffbe2938 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){
@@ -36,13 +38,37 @@ 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;
+}
+
+/**
+*
+* 56495332 00096ebd 00000077 —> tag id 618173
+* aaaaaaaa iiiiiiii -----..c
+*
+* a = fixed value  ascii 'VIS2'
+* i = card id
+* c = checksum  (xor of card id)
+* . = unknown 
+* 
+**/
 //see ASKDemod for what args are accepted
 int CmdVisa2kDemod(const char *Cmd) {
 
+       // save GraphBuffer - to restore it later       
+       save_restoreGB(1);
+       
+       //sCmdAskEdgeDetect("");
+       
        //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");
+               save_restoreGB(0);
                return 0;
        }
        size_t size = DemodBufferLen;
@@ -58,34 +84,42 @@ int CmdVisa2kDemod(const char *Cmd) {
                        else
                                PrintAndLog("DEBUG: Error - Visa2k: ans: %d", ans);
                }
+               save_restoreGB(0);
                return 0;
        }
        setDemodBuf(DemodBuffer, 96, ans);
-       
+       setGrid_Clock(64);
+               
        //got a good demod
        uint32_t raw1 = bytebits_to_byte(DemodBuffer, 32);
        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);
+               save_restoreGB(0);
+               return 0;
+       }
        PrintAndLog("Visa2000 Tag Found: Card ID %u,  Raw: %08X%08X%08X", raw2,  raw1 ,raw2, raw3);
+       save_restoreGB(0);
        return 1;
 }
 
 int CmdVisa2kRead(const char *Cmd) {
        CmdLFRead("s");
-       getSamples("20000",TRUE);
+       getSamples("12000",TRUE);
        return CmdVisa2kDemod(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();
 
@@ -94,26 +128,18 @@ int CmdVisa2kClone(const char *Cmd) {
        //Q5
        if (param_getchar(Cmd, 1) == 'Q' || param_getchar(Cmd, 1) == 'q') {
                //t5555 (Q5) BITRATE = (RF-2)/2 (iceman)
-               blocks[0] = T5555_MODULATION_MANCHESTER | 64<<T5555_BITRATE_SHIFT | T5555_ST_TERMINATOR | 3<<T5555_MAXBLOCK_SHIFT;
+               blocks[0] = T5555_MODULATION_MANCHESTER | ((64-2)>>1) << 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}};
@@ -123,7 +149,7 @@ int CmdVisa2kClone(const char *Cmd) {
                c.arg[1] = i;
                clearCommandBuffer();
                SendCommand(&c);
-               if (!WaitForResponseTimeout(CMD_ACK, &resp, 1000)){
+               if (!WaitForResponseTimeout(CMD_ACK, &resp, T55XX_WRITE_TIMEOUT)){
                        PrintAndLog("Error occurred, device did not respond during write operation.");
                        return -1;
                }
@@ -148,12 +174,12 @@ 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;