Implement card reading with a few simple fixed obfuscation strings

diff --git a/armsrc/legicrf.c b/armsrc/legicrf.c
index 7c3460af0fe2a13397c00b45cbe73df14da286c4..86c0c3604f1b6074e1f07f0aaf74d367b12910b7 100644 (file)
--- a/armsrc/legicrf.c
+++ b/armsrc/legicrf.c
@@ -80,6 +80,7 @@ static void frame_send_rwd(uint16_t data, int bits)
        
        /* Reset the timer, to measure time until the start of the tag frame */
        timer->TC_CCR = AT91C_TC_SWTRG;
+       while(timer->TC_CV > 1) ; /* Wait till the clock has reset */
 }
 
 /* Receive a frame from the card in reader emulation mode, the FPGA and
@@ -140,6 +141,10 @@ static void frame_receive_rwd(struct legic_frame * const f, int bits)
        
        f->data = data;
        f->bits = bits;
+       
+       /* Reset the timer, to synchronize the next frame */
+       timer->TC_CCR = AT91C_TC_SWTRG;
+       while(timer->TC_CV > 1) ; /* Wait till the clock has reset */
 }
 
 static void frame_clean(struct legic_frame * const f)
@@ -148,6 +153,31 @@ static void frame_clean(struct legic_frame * const f)
        f->bits = 0;
 }
 
+static uint16_t perform_setup_phase_rwd(void)
+{
+       
+       /* Switch on carrier and let the tag charge for 1ms */
+       AT91C_BASE_PIOA->PIO_SODR = GPIO_SSC_DOUT;
+       SpinDelay(1);
+       
+       frame_send_rwd(0x55, 7);
+       frame_clean(&current_frame);
+       frame_receive_rwd(&current_frame, 6);
+       while(timer->TC_CV < 387) ; /* ~ 258us */
+       frame_send_rwd(0x019, 6);
+       
+       return current_frame.data ^ 0x26;
+}
+
+static void switch_off_tag_rwd(void)
+{
+       /* Switch off carrier, make sure tag is reset */
+       AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
+       SpinDelay(10);
+       
+       WDT_HIT();
+}
+
 void LegicRfReader(void)
 {
        SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
@@ -161,25 +191,62 @@ void LegicRfReader(void)
        
        setup_timer();
        
-       while(!BUTTON_PRESS()) {
-               /* Switch on carrier and let the tag charge for 1ms */
-               AT91C_BASE_PIOA->PIO_SODR = GPIO_SSC_DOUT;
-               SpinDelay(1);
-               
-               LED_A_ON();
-               frame_send_rwd(queries[0].data, queries[0].bits);
-               LED_A_OFF();
+       memset(BigBuf, 0, 1024);
+       
+       int byte_index = 0, card_size = 0, command_size = 0;
+       uint16_t command_obfuscation = 0x57, response_obfuscation = 0;
+       uint16_t tag_type = perform_setup_phase_rwd();
+       switch_off_tag_rwd();
+       
+       int error = 0;
+       switch(tag_type) {
+       case 0x1d:
+               DbpString("MIM 256 card found, reading card ...");
+               command_size = 9;
+               card_size = 256;
+               response_obfuscation = 0x52;
+               break;
+       case 0x3d:
+               DbpString("MIM 1024 card found, reading card ...");
+               command_size = 11;
+               card_size = 1024;
+               response_obfuscation = 0xd4;
+               break;
+       default:
+               DbpString("No or unknown card found, aborting");
+               error = 1;
+               break;
+       }
+       
+       LED_B_ON();
+       while(!BUTTON_PRESS() && (byte_index<card_size)) {
+               if(perform_setup_phase_rwd() != tag_type) {
+                       DbpString("Card removed, aborting");
+                       switch_off_tag_rwd();
+                       error=1;
+                       break;
+               }
                
+               while(timer->TC_CV < 387) ; /* ~ 258us */
+               frame_send_rwd(command_obfuscation ^ (byte_index<<1), command_size);
                frame_clean(&current_frame);
-               LED_B_ON();
-               frame_receive_rwd(&current_frame, responses[0].bits);
-               LED_B_OFF();
+               frame_receive_rwd(&current_frame, 8);
+               ((uint8_t*)BigBuf)[byte_index] = (current_frame.data ^ response_obfuscation) & 0xff;
                
-               /* Switch off carrier, make sure tag is reset */
-               AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
-               SpinDelay(10);
+               switch_off_tag_rwd();
                
                WDT_HIT();
+               byte_index++;
+               if(byte_index & 0x04) LED_C_ON(); else LED_C_OFF();
        }
+       LED_B_OFF();
+       LED_C_OFF();
        
+       if(!error) {
+               if(card_size == 256) {
+                       DbpString("Card read, use hexsamples 256 to view results");
+               } else if(card_size == 1024) {
+                       DbpString("Card read, use hexsamples 1024 to view results");
+               }
+       }
 }