]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - client/cmdhflegic.c
CHG: free the malloc:d memory in the crc8 function.
[proxmark3-svn] / client / cmdhflegic.c
index 21598bcddeee1e137692e57e0dc10ba0a2a0e6d9..0262f81c5560a7e1160b9dde859d7fb9f8d26e04 100644 (file)
@@ -38,9 +38,20 @@ int usage_legic_load(void){
        return 0;
 }
 
+int usage_legic_read(void){    
+       PrintAndLog("Read data from a legic tag.");
+       PrintAndLog("Usage:  hf legic read <offset> <num of bytes>");
+       PrintAndLog("Options :");
+       PrintAndLog("  <offset>        : offset in data array to start download from");
+       PrintAndLog("  <num of bytes>  : number of bytes to download");
+       PrintAndLog("");
+       PrintAndLog(" sample: hf legic read");
+       return 0;
+}
+
 /*
  *  Output BigBuf and deobfuscate LEGIC RF tag data.
- *   This is based on information given in the talk held
+ *  This is based on information given in the talk held
  *  by Henryk Ploetz and Karsten Nohl at 26c3
  */
 int CmdLegicDecode(const char *Cmd) {
@@ -53,19 +64,22 @@ int CmdLegicDecode(const char *Cmd) {
        int crc = 0;
        int wrp = 0;
        int wrc = 0;
-       uint8_t data_buf[1200]; // receiver buffer,  should be 1024..
+       uint8_t data_buf[1024]; // receiver buffer,  should be 1024..
        char token_type[4];
 
-       // copy data from proxmark into buffer
-       GetFromBigBuf(data_buf,sizeof(data_buf),0);
-       WaitForResponse(CMD_ACK,NULL);
-
+       // download EML memory, where the "legic read" command puts the data.
+       GetEMLFromBigBuf(data_buf, sizeof(data_buf), 0);
+       if ( !WaitForResponseTimeout(CMD_ACK, NULL, 2000)){
+               PrintAndLog("Command execute timeout");
+               return 1;
+       }
+       
        // 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("------------------------------------------------------");
        PrintAndLog("MCD: %02x, MSN: %02x %02x %02x, MCC: %02x %s",
                data_buf[0],
                data_buf[1],
@@ -92,7 +106,7 @@ int CmdLegicDecode(const char *Cmd) {
 
        stamp_len = 0xfc - data_buf[6];
 
-       PrintAndLog("DCF: %02x %02x, Token_Type=%s (OLE=%01u), Stamp_len=%02u",
+       PrintAndLog("DCF: %02x %02x, Token Type=%s (OLE=%01u), Stamp len=%02u",
                data_buf[5],
                data_buf[6],
                token_type,
@@ -115,9 +129,27 @@ int CmdLegicDecode(const char *Cmd) {
        uint32_t segCalcCRC = 0;
        uint32_t segCRC = 0;
 
+       // see if user area is xored or just zeros.
+       int numOfZeros = 0;
+       for (int index=22; index < 256; ++index){
+               if ( data_buf[index] == 0x00 )
+                       ++numOfZeros;
+       }
+       // if possible zeros is less then 60%, lets assume data is xored
+       // 256  - 22 (header) = 234
+       // 1024 - 22 (header) = 1002
+       int isXored = (numOfZeros*100/stamp_len) < 50;
+       PrintAndLog("is data xored?  %d  ( %d %)", isXored, (numOfZeros*100/stamp_len));
+
+       print_hex_break( data_buf, 33, 16);
+       
+       return 0;
+       
        PrintAndLog("\nADF: User Area");
+       PrintAndLog("------------------------------------------------------");
        i = 22;  
        // 64 potential segements
+       // how to detect there is no segments?!?
        for ( segmentNum=0; segmentNum<64; segmentNum++ ) {
                segment_len = ((data_buf[i+1]^crc)&0x0f) * 256 + (data_buf[i]^crc);
                segment_flag = ((data_buf[i+1]^crc)&0xf0)>>4;
@@ -143,16 +175,16 @@ int CmdLegicDecode(const char *Cmd) {
                segCalcCRC = CRC8Legic(segCrcBytes, 8);
                segCRC = data_buf[i+4]^crc;
 
-               PrintAndLog("Segment %02u: raw header=%02x %02x %02x %02x, flag=%01x (valid=%01u, last=%01u), len=%04u, WRP=%02u, WRC=%02u, RD=%01u, CRC=%02x  (%s)",
+               PrintAndLog("Segment %02u \nraw header | 0x%02X 0x%02X 0x%02X 0x%02X \nSegment len: %u,  Flag: 0x%X (valid:%01u, last:%01u), WRP: %02u, WRC: %02u, RD: %01u, CRC: 0x%02X (%s)",
                        segmentNum,
                        data_buf[i]^crc,
                        data_buf[i+1]^crc,
                        data_buf[i+2]^crc,
                        data_buf[i+3]^crc,
+                       segment_len, 
                        segment_flag,
                        (segment_flag & 0x4) >> 2,
                        (segment_flag & 0x8) >> 3,
-                       segment_len,
                        wrp,
                        wrc,
                        ((data_buf[i+3]^crc) & 0x80) >> 7,
@@ -164,50 +196,51 @@ int CmdLegicDecode(const char *Cmd) {
     
                if ( hasWRC ) {
                        PrintAndLog("WRC protected area:   (I %d | K %d| WRC %d)", i, k, wrc);
-                       
-                       for ( k=i; k < wrc; k++)
-                               data_buf[k] ^= crc;
-                       
-                       //is WRC / 8? 
-                       
-                       // for ( k=i; k < wrc; k += 8)
-                       PrintAndLog("%s", sprint_hex( data_buf+i, wrc ) );
+                       PrintAndLog("\nrow  | data");
+                       PrintAndLog("-----+------------------------------------------------");
+                       // de-xor?  if not zero, assume it needs xoring.
+                       if ( isXored) {
+                               for ( k=i; k < wrc; ++k)
+                                       data_buf[k] ^= crc;
+                       }
+                       print_hex_break( data_buf+i, wrc, 16);
                        
                        i += wrc;
                }
     
                if ( hasWRP ) {
                        PrintAndLog("Remaining write protected area:  (I %d | K %d | WRC %d | WRP %d  WRP_LEN %d)",i, k, wrc, wrp, wrp_len);
+                       PrintAndLog("\nrow  | data");
+                       PrintAndLog("-----+------------------------------------------------");
 
-                       // // de-xor?
-                       // if ( data_buf[k] > 0) {
-                               // for (k=i; k < wrp_len; k++)
-                                       // data_buf[k] ^= crc;
-                       // }
+                       if (isXored) {
+                               for (k=i; k < wrp_len; ++k)
+                                       data_buf[k] ^= crc;
+                       }
                        
-                       // for (k=i; k < wrp_len; k += 16) {
-                               
-                       PrintAndLog("%s", sprint_hex( data_buf+i, wrp_len));
-                       // }
+                       print_hex_break( data_buf+i, wrp_len, 16);
                        
                        i += wrp_len;
                        
-                       // if( wrp_len == 8 )
-                               // PrintAndLog("Card ID: %2X%02X%02X", data_buf[i-4]^crc, data_buf[i-3]^crc, data_buf[i-2]^crc);                        
+                       // does this one work?
+                       if( wrp_len == 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:");
-               
-               // if ( data_buf[k] > 0 ) {
-                       // for ( k=i; k < remain_seg_payload_len; k++)
-                               // data_buf[k] ^= crc;
-               // }
+               PrintAndLog("Remaining segment payload:  (I %d | K %d | Remain LEN %d)", i, k, remain_seg_payload_len);
+               PrintAndLog("\nrow  | data");
+               PrintAndLog("-----+------------------------------------------------");
+               if ( isXored ) {
+                       for ( k=i; k < remain_seg_payload_len; ++k)
+                               data_buf[k] ^= crc;
+               }
                
-               // for ( k=i; k < remain_seg_payload_len; k++)
-               PrintAndLog("%s", sprint_hex( data_buf+i, remain_seg_payload_len )  );
+               print_hex_break( data_buf+i, remain_seg_payload_len, 16);
     
                i += remain_seg_payload_len;
                
+               PrintAndLog("-----+------------------------------------------------\n");
+
                // end with last segment
                if (segment_flag & 0x8) return 0;
 
@@ -216,6 +249,13 @@ int CmdLegicDecode(const char *Cmd) {
 }
 
 int CmdLegicRFRead(const char *Cmd) {
+       
+       // params:
+       // offset in data
+       // number of bytes.
+       char cmdp = param_getchar(Cmd, 0);
+       if ( cmdp == 'H' || cmdp == 'h' ) return usage_legic_read();
+       
        int byte_count=0, offset=0;
        sscanf(Cmd, "%i %i", &offset, &byte_count);
        if(byte_count == 0) byte_count = -1;
@@ -329,15 +369,18 @@ int CmdLegicSave(const char *Cmd) {
                return 0;
        }
 
+       GetFromBigBuf(got, requested, offset);
+       if ( !WaitForResponseTimeout(CMD_ACK, NULL, 2000)){
+               PrintAndLog("Command execute timeout"); 
+               return 1;
+       }
+
        FILE *f = fopen(filename, "w");
        if(!f) {
                PrintAndLog("couldn't open '%s'", Cmd+1);
                return -1;
        }
-
-       GetFromBigBuf(got, requested, offset);
-       WaitForResponse(CMD_ACK, NULL);
-
+       
        for (int j = 0; j < requested; j += 8) {
                fprintf(f, "%02x %02x %02x %02x %02x %02x %02x %02x\n",
                        got[j+0], got[j+1], got[j+2], got[j+3],
@@ -352,6 +395,7 @@ int CmdLegicSave(const char *Cmd) {
        return 0;
 }
 
+//TODO: write a help text (iceman)
 int CmdLegicRfSim(const char *Cmd) {
        UsbCommand c = {CMD_SIMULATE_TAG_LEGIC_RF, {6,3,0}};
        sscanf(Cmd, " %"lli" %"lli" %"lli, &c.arg[0], &c.arg[1], &c.arg[2]);
@@ -360,6 +404,7 @@ int CmdLegicRfSim(const char *Cmd) {
        return 0;
 }
 
+//TODO: write a help text (iceman)
 int CmdLegicRfWrite(const char *Cmd) {
     UsbCommand c = {CMD_WRITER_LEGIC_RF};
     int res = sscanf(Cmd, " 0x%"llx" 0x%"llx, &c.arg[0], &c.arg[1]);
@@ -399,12 +444,16 @@ int CmdLegicRfFill(const char *Cmd) {
 int CmdLegicCalcCrc8(const char *Cmd){
 
        int len =  strlen(Cmd); 
-       if (len & 1 ) return usage_legic_calccrc8(); 
+       if ( len & 1 ) return usage_legic_calccrc8(); 
        
-       uint8_t *data = malloc(len);
+       // add 1 for null terminator.
+       uint8_t *data = malloc(len+1);
        if ( data == NULL ) return 1;
                
-       param_gethex(Cmd, 0, data, len );
+       if (param_gethex(Cmd, 0, data, len )) {
+               free(data);
+               return usage_legic_calccrc8();  
+       }
        
        uint32_t checksum =  CRC8Legic(data, len/2);    
        PrintAndLog("Bytes: %s || CRC8: %X", sprint_hex(data, len/2), checksum );
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