]> cvs.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/hitag2.c
more coverity fixes
[proxmark3-svn] / armsrc / hitag2.c
index 4b173d6f223845620eeb47e96e35c89ffb78f628..dd0211da98785ce6dbbf381193ae4371eb4c8714 100644 (file)
@@ -340,7 +340,7 @@ static void hitag2_handle_reader_command(byte_t* rx, const size_t rxlen, byte_t*
                                
                                // Unknown command
                                default:
-                                       Dbprintf("Uknown command: %02x %02x",rx[0],rx[1]);
+                                       Dbprintf("Unknown command: %02x %02x",rx[0],rx[1]);
                                        return;
                                break;
                        }
@@ -411,7 +411,7 @@ static void hitag_reader_send_bit(int bit) {
        // Binary puls length modulation (BPLM) is used to encode the data stream
        // This means that a transmission of a one takes longer than that of a zero
        
-       // Enable modulation, which means, drop the the field
+       // Enable modulation, which means, drop the field
        HIGH(GPIO_SSC_DOUT);
        
        // Wait for 4-10 times the carrier period
@@ -442,7 +442,7 @@ static void hitag_reader_send_frame(const byte_t* frame, size_t frame_len)
        }
        // Send EOF 
        AT91C_BASE_TC0->TC_CCR = AT91C_TC_SWTRG;
-       // Enable modulation, which means, drop the the field
+       // Enable modulation, which means, drop the field
        HIGH(GPIO_SSC_DOUT);
        // Wait for 4-10 times the carrier period
        while(AT91C_BASE_TC0->TC_CV < T0*6);
@@ -697,6 +697,42 @@ static bool hitag2_test_auth_attempts(byte_t* rx, const size_t rxlen, byte_t* tx
        return true;
 }
 
+static bool hitag2_read_uid(byte_t* rx, const size_t rxlen, byte_t* tx, size_t* txlen) {
+       // Reset the transmission frame length
+       *txlen = 0;
+
+       // Try to find out which command was send by selecting on length (in bits)
+       switch (rxlen) {
+               // No answer, try to resurrect
+               case 0: {
+                       // Just starting or if there is no answer
+                       *txlen = 5;
+                       memcpy(tx,"\xc0",nbytes(*txlen));
+               } break;
+               // Received UID
+               case 32: {
+                       // Check if we received answer tag (at)
+                       if (bAuthenticating) {
+                               bAuthenticating = false;
+                       } else {
+                               // Store the received block
+                               memcpy(tag.sectors[blocknr],rx,4);
+                               blocknr++;
+                       }
+                       if (blocknr > 0) {
+                               //DbpString("Read successful!");
+                               bSuccessful = true;
+                               return false;
+                       }
+               } break;
+               // Unexpected response
+               default: {
+                       Dbprintf("Uknown frame length: %d",rxlen);
+                       return false;
+               } break;
+       }
+       return true;
+}
 
 void SnoopHitag(uint32_t type) {
        int frame_count;
@@ -710,22 +746,24 @@ void SnoopHitag(uint32_t type) {
        byte_t rx[HITAG_FRAME_LEN];
        size_t rxlen=0;
        
+       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+
+       // Clean up trace and prepare it for storing frames
+       set_tracing(TRUE);
+       clear_trace();
+       
        auth_table_len = 0;
        auth_table_pos = 0;
+
        BigBuf_free();
     auth_table = (byte_t *)BigBuf_malloc(AUTH_TABLE_LENGTH);
        memset(auth_table, 0x00, AUTH_TABLE_LENGTH);
 
-       // Clean up trace and prepare it for storing frames
-       set_tracing(TRUE);
-       clear_trace();
-       
        DbpString("Starting Hitag2 snoop");
        LED_D_ON();
        
        // Set up eavesdropping mode, frequency divisor which will drive the FPGA
        // and analog mux selection.
-       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
        FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_EDGE_DETECT  | FPGA_LF_EDGE_DETECT_TOGGLE_MODE);
        FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
        SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
@@ -922,6 +960,12 @@ void SimulateHitagTag(bool tag_mem_supplied, byte_t* data) {
        bool bQuitTraceFull = false;
        bQuiet = false;
        
+       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
+
+       // Clean up trace and prepare it for storing frames
+       set_tracing(TRUE);
+       clear_trace();
+
        auth_table_len = 0;
        auth_table_pos = 0;
     byte_t* auth_table;
@@ -929,10 +973,6 @@ void SimulateHitagTag(bool tag_mem_supplied, byte_t* data) {
     auth_table = (byte_t *)BigBuf_malloc(AUTH_TABLE_LENGTH);
        memset(auth_table, 0x00, AUTH_TABLE_LENGTH);
 
-       // Clean up trace and prepare it for storing frames
-       set_tracing(TRUE);
-       clear_trace();
-
        DbpString("Starting Hitag2 simulation");
        LED_D_ON();
        hitag2_init();
@@ -953,8 +993,7 @@ void SimulateHitagTag(bool tag_mem_supplied, byte_t* data) {
        
        // Set up simulator mode, frequency divisor which will drive the FPGA
        // and analog mux selection.
-       FpgaDownloadAndGo(FPGA_BITSTREAM_LF);
-       FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_EDGE_DETECT | FPGA_LF_EDGE_DETECT_READER_FIELD);
+       FpgaWriteConfWord(FPGA_MAJOR_MODE_LF_EDGE_DETECT);
        FpgaSendCommand(FPGA_CMD_SET_DIVISOR, 95); //125Khz
        SetAdcMuxFor(GPIO_MUXSEL_LOPKD);
        RELAY_OFF();
@@ -1120,19 +1159,18 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
        set_tracing(TRUE);
        clear_trace();
 
-       DbpString("Starting Hitag reader family");
+       //DbpString("Starting Hitag reader family");
 
        // Check configuration
        switch(htf) {
                case RHT2F_PASSWORD: {
                        Dbprintf("List identifier in password mode");
                        memcpy(password,htd->pwd.password,4);
-               blocknr = 0;
+                       blocknr = 0;
                        bQuitTraceFull = false;
                        bQuiet = false;
                        bPwd = false;
                } break;
-      
                case RHT2F_AUTHENTICATE: {
                        DbpString("Authenticating using nr,ar pair:");
                        memcpy(NrAr,htd->auth.NrAr,8);
@@ -1142,10 +1180,9 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                        bAuthenticating = false;
                        bQuitTraceFull = true;
                } break;
-      
                case RHT2F_CRYPTO: {
                        DbpString("Authenticating using key:");
-                       memcpy(key,htd->crypto.key,4);    //HACK; 4 or 6??  I read both in the code.
+                       memcpy(key,htd->crypto.key,6);    //HACK; 4 or 6??  I read both in the code.
                        Dbhexdump(6,key,false);
                        blocknr = 0;
                        bQuiet = false;
@@ -1153,7 +1190,6 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                        bAuthenticating = false;
                        bQuitTraceFull = true;
                } break;
-
                case RHT2F_TEST_AUTH_ATTEMPTS: {
                        Dbprintf("Testing %d authentication attempts",(auth_table_len/8));
                        auth_table_pos = 0;
@@ -1162,7 +1198,13 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                        bQuiet = false;
                        bCrypto = false;
                } break;
-                       
+               case RHT2F_UID_ONLY: {
+                       blocknr = 0;
+                       bQuiet = false;
+                       bCrypto = false;
+                       bAuthenticating = false;
+                       bQuitTraceFull = true;
+               } break;
                default: {
                        Dbprintf("Error, unknown function: %d",htf);
                        return;
@@ -1219,22 +1261,22 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
     // hitagS settings
     reset_sof = 1;
     t_wait = 200;
-    DbpString("Configured for hitagS reader");
+    //DbpString("Configured for hitagS reader");
   } else if (htf < 20) {
     // hitag1 settings
     reset_sof = 1;
     t_wait = 200;
-    DbpString("Configured for hitag1 reader");
+    //DbpString("Configured for hitag1 reader");
   } else if (htf < 30) {
     // hitag2 settings
     reset_sof = 4;
     t_wait = HITAG_T_WAIT_2;
-    DbpString("Configured for hitag2 reader");
+    //DbpString("Configured for hitag2 reader");
        } else {
     Dbprintf("Error, unknown hitag reader type: %d",htf);
     return;
   }
-               
+       uint8_t attempt_count=0;
        while(!bStop && !BUTTON_PRESS()) {
                // Watchdog hit
                WDT_HIT();
@@ -1269,6 +1311,11 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                        case RHT2F_TEST_AUTH_ATTEMPTS: {
                                bStop = !hitag2_test_auth_attempts(rx,rxlen,tx,&txlen);
                        } break;
+                       case RHT2F_UID_ONLY: {
+                               bStop = !hitag2_read_uid(rx, rxlen, tx, &txlen);
+                               attempt_count++; //attempt 3 times to get uid then quit
+                               if (!bStop && attempt_count == 3) bStop = true;
+                       } break;
                        default: {
                                Dbprintf("Error, unknown function: %d",htf);
                                return;
@@ -1285,6 +1332,8 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                // we need to wait (T_Wait2 + half_tag_period) when the last was a 'one'.
                // All timer values are in terms of T0 units
                while(AT91C_BASE_TC0->TC_CV < T0*(t_wait+(HITAG_T_TAG_HALF_PERIOD*lastbit)));
+                       
+                       //Dbprintf("DEBUG: Sending reader frame");
                
                // Transmit the reader frame
                hitag_reader_send_frame(tx,txlen);
@@ -1314,7 +1363,9 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                bSkip = true;
                tag_sof = reset_sof;
                response = 0;
-               
+                       //Dbprintf("DEBUG: Waiting to receive frame");
+               uint32_t errorCount = 0;
+
                // Receive frame, watch for at most T0*EOF periods
                while (AT91C_BASE_TC1->TC_CV < T0*HITAG_T_WAIT_MAX) {
                        // Check if falling edge in tag modulation is detected
@@ -1330,19 +1381,29 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                                // Capture tag frame (manchester decoding using only falling edges)
                                if(ra >= HITAG_T_EOF) {
                                        if (rxlen != 0) {
-                                               //DbpString("wierd1?");
+                                               //Dbprintf("DEBUG: Wierd1");
                                        }
                                        // Capture the T0 periods that have passed since last communication or field drop (reset)
                                        // We always recieve a 'one' first, which has the falling edge after a half period |-_|
                                        response = ra-HITAG_T_TAG_HALF_PERIOD;
                                } else if(ra >= HITAG_T_TAG_CAPTURE_FOUR_HALF) {
                                        // Manchester coding example |-_|_-|-_| (101)
+
+                                       //need to test to verify we don't exceed memory...
+                                       //if ( ((rxlen+2) / 8) > HITAG_FRAME_LEN) {
+                                       //      break;
+                                       //}
                                        rx[rxlen / 8] |= 0 << (7-(rxlen%8));
                                        rxlen++;
                                        rx[rxlen / 8] |= 1 << (7-(rxlen%8));
                                        rxlen++;
                                } else if(ra >= HITAG_T_TAG_CAPTURE_THREE_HALF) {
                                        // Manchester coding example |_-|...|_-|-_| (0...01)
+                                       
+                                       //need to test to verify we don't exceed memory...
+                                       //if ( ((rxlen+2) / 8) > HITAG_FRAME_LEN) {
+                                       //      break;
+                                       //}
                                        rx[rxlen / 8] |= 0 << (7-(rxlen%8));
                                        rxlen++;
                                        // We have to skip this half period at start and add the 'one' the second time 
@@ -1354,6 +1415,11 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                                        bSkip = !bSkip;
                                } else if(ra >= HITAG_T_TAG_CAPTURE_TWO_HALF) {
                                        // Manchester coding example |_-|_-| (00) or |-_|-_| (11)
+
+                                       //need to test to verify we don't exceed memory...
+                                       //if ( ((rxlen+2) / 8) > HITAG_FRAME_LEN) {
+                                       //      break;
+                                       //}
                                        if (tag_sof) {
                                                // Ignore bits that are transmitted during SOF
                                                tag_sof--;
@@ -1363,22 +1429,27 @@ void ReaderHitag(hitag_function htf, hitag_data* htd) {
                                                rxlen++;
                                        }
                                } else {
+                                               //Dbprintf("DEBUG: Wierd2");
+                                               errorCount++;
                                        // Ignore wierd value, is to small to mean anything
                                }
                        }
-
+                       //if we saw over 100 wierd values break it probably isn't hitag...
+                       if (errorCount >100) break;
                        // We can break this loop if we received the last bit from a frame
                        if (AT91C_BASE_TC1->TC_CV > T0*HITAG_T_EOF) {
                                if (rxlen>0) break;
                        }
                }
        }
+       //Dbprintf("DEBUG: Done waiting for frame");
+       
        LED_B_OFF();
        LED_D_OFF();
        AT91C_BASE_TC1->TC_CCR = AT91C_TC_CLKDIS;
        AT91C_BASE_TC0->TC_CCR = AT91C_TC_CLKDIS;
        FpgaWriteConfWord(FPGA_MAJOR_MODE_OFF);
-       Dbprintf("frame received: %d",frame_count);
-  DbpString("All done");
-  cmd_send(CMD_ACK,bSuccessful,0,0,(byte_t*)tag.sectors,48);
+       //Dbprintf("frame received: %d",frame_count);
+       //DbpString("All done");
+       cmd_send(CMD_ACK,bSuccessful,0,0,(byte_t*)tag.sectors,48);
 }
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