]> cvs.zerfleddert.de Git - proxmark3-svn/blob - client/cmdlfgproxii.c
fix bug in st detect +
[proxmark3-svn] / client / cmdlfgproxii.c
1 //-----------------------------------------------------------------------------
2 //
3 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
4 // at your option, any later version. See the LICENSE.txt file for the text of
5 // the license.
6 //-----------------------------------------------------------------------------
7 // Low frequency G Prox II tag commands
8 //-----------------------------------------------------------------------------
9 #include <stdio.h>
10 #include <string.h>
11 #include <inttypes.h>
12 #include "cmdlfgproxii.h"
13 #include "proxmark3.h"
14 #include "ui.h"
15 #include "util.h"
16 #include "graph.h"
17 #include "cmdparser.h"
18 #include "cmddata.h"
19 #include "cmdmain.h"
20 #include "cmdlf.h"
21 #include "lfdemod.h"
22 static int CmdHelp(const char *Cmd);
23
24 //by marshmellow
25 //attempts to demodulate and identify a G_Prox_II verex/chubb card
26 //WARNING: if it fails during some points it will destroy the DemodBuffer data
27 // but will leave the GraphBuffer intact.
28 //if successful it will push askraw data back to demod buffer ready for emulation
29 int CmdG_Prox_II_Demod(const char *Cmd)
30 {
31 if (!ASKbiphaseDemod(Cmd, false)){
32 if (g_debugMode) PrintAndLog("Error gProxII: ASKbiphaseDemod failed 1st try");
33 return 0;
34 }
35 size_t size = DemodBufferLen;
36 //call lfdemod.c demod for gProxII
37 int ans = gProxII_Demod(DemodBuffer, &size);
38 if (ans < 0){
39 if (g_debugMode) PrintAndLog("Error gProxII_Demod");
40 return 0;
41 }
42 //got a good demod of 96 bits
43 uint8_t ByteStream[8] = {0x00};
44 uint8_t xorKey=0;
45 size_t startIdx = ans + 6; //start after 6 bit preamble
46
47 uint8_t bits_no_spacer[90];
48 //so as to not mess with raw DemodBuffer copy to a new sample array
49 memcpy(bits_no_spacer, DemodBuffer + startIdx, 90);
50 // remove the 18 (90/5=18) parity bits (down to 72 bits (96-6-18=72))
51 size_t bitLen = removeParity(bits_no_spacer, 0, 5, 3, 90); //source, startloc, paritylen, ptype, length_to_run
52 if (bitLen != 72) {
53 if (g_debugMode) PrintAndLog("Error gProxII: spacer removal did not produce 72 bits: %u, start: %u", bitLen, startIdx);
54 return 0;
55 }
56 // get key and then get all 8 bytes of payload decoded
57 xorKey = (uint8_t)bytebits_to_byteLSBF(bits_no_spacer, 8);
58 for (size_t idx = 0; idx < 8; idx++) {
59 ByteStream[idx] = ((uint8_t)bytebits_to_byteLSBF(bits_no_spacer+8 + (idx*8),8)) ^ xorKey;
60 if (g_debugMode) PrintAndLog("byte %u after xor: %02x", (unsigned int)idx, ByteStream[idx]);
61 }
62 //now ByteStream contains 8 Bytes (64 bits) of decrypted raw tag data
63 //
64 uint8_t fmtLen = ByteStream[0]>>2;
65 uint32_t FC = 0;
66 uint32_t Card = 0;
67 //get raw 96 bits to print
68 uint32_t raw1 = bytebits_to_byte(DemodBuffer+ans,32);
69 uint32_t raw2 = bytebits_to_byte(DemodBuffer+ans+32, 32);
70 uint32_t raw3 = bytebits_to_byte(DemodBuffer+ans+64, 32);
71
72 if (fmtLen==36){
73 FC = ((ByteStream[3] & 0x7F)<<7) | (ByteStream[4]>>1);
74 Card = ((ByteStream[4]&1)<<19) | (ByteStream[5]<<11) | (ByteStream[6]<<3) | (ByteStream[7]>>5);
75 PrintAndLog("G-Prox-II Found: FmtLen %d, FC %u, Card %u", (int)fmtLen, FC, Card);
76 } else if(fmtLen==26){
77 FC = ((ByteStream[3] & 0x7F)<<1) | (ByteStream[4]>>7);
78 Card = ((ByteStream[4]&0x7F)<<9) | (ByteStream[5]<<1) | (ByteStream[6]>>7);
79 PrintAndLog("G-Prox-II Found: FmtLen %d, FC %u, Card %u", (int)fmtLen, FC, Card);
80 } else {
81 PrintAndLog("Unknown G-Prox-II Fmt Found: FmtLen %d",(int)fmtLen);
82 PrintAndLog("Decoded Raw: %s", sprint_hex(ByteStream, 8));
83 }
84 PrintAndLog("Raw: %08x%08x%08x", raw1,raw2,raw3);
85 setDemodBuf(DemodBuffer+ans, 96, 0);
86 return 1;
87 }
88 //by marshmellow
89 //see ASKDemod for what args are accepted
90 int CmdG_Prox_II_Read(const char *Cmd) {
91 // read lf silently
92 CmdLFRead("s");
93 // get samples silently
94 getSamples("10000",false);
95 // demod and output viking ID
96 return CmdG_Prox_II_Demod(Cmd);
97 }
98
99 static command_t CommandTable[] = {
100 {"help", CmdHelp, 1, "This help"},
101 {"demod", CmdG_Prox_II_Demod, 1, "Demodulate a G Prox II tag from the GraphBuffer"},
102 {"read", CmdG_Prox_II_Read, 0, "Attempt to read and Extract tag data from the antenna"},
103 {NULL, NULL, 0, NULL}
104 };
105
106 int CmdLF_G_Prox_II(const char *Cmd) {
107 CmdsParse(CommandTable, Cmd);
108 return 0;
109 }
110
111 int CmdHelp(const char *Cmd) {
112 CmdsHelp(CommandTable);
113 return 0;
114 }
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