started fixing the paritiy == 0 special attack against chinese clones with bad prng...

[proxmark3-svn] / armsrc / hfsnoop.c

diff --git a/armsrc/hfsnoop.c b/armsrc/hfsnoop.c
index 755c24f6c1e47a8a6f1ab4c5e28827037721b82f..4af8522a5d91b2ea9be7b4da20b65be1320f3c9d 100644 (file)
--- a/armsrc/hfsnoop.c
+++ b/armsrc/hfsnoop.c
@@ -7,7 +7,6 @@ static void RAMFUNC optimizedSnoop(void);
 
 static void RAMFUNC optimizedSnoop(void)
 {
-       BigBuf_free();
        int n = BigBuf_max_traceLen() / sizeof(uint16_t); // take all memory
 
        uint16_t *dest = (uint16_t *)BigBuf_get_addr();
@@ -20,7 +19,7 @@ static void RAMFUNC optimizedSnoop(void)
                if(AT91C_BASE_SSC->SSC_SR & AT91C_SSC_RXRDY)
                {
                        *dest = (uint16_t)(AT91C_BASE_SSC->SSC_RHR);
-                       dest++;
+                       ++dest;
                }
        }
        //Resetting Frame mode (First set in fpgaloader.c)
@@ -29,8 +28,11 @@ static void RAMFUNC optimizedSnoop(void)
 
 void HfSnoop(int samplesToSkip, int triggersToSkip)
 {
+       BigBuf_free(); BigBuf_Clear();
+       
        Dbprintf("Skipping first %d sample pairs, Skipping %d triggers.\n", samplesToSkip, triggersToSkip);
        bool trigger_cnt;
+
        LED_D_ON();
        // Select correct configs
        FpgaDownloadAndGo(FPGA_BITSTREAM_HF);
@@ -40,32 +42,35 @@ void HfSnoop(int samplesToSkip, int triggersToSkip)
        SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
        FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_SNOOP);
        SpinDelay(100);
-
+       
        AT91C_BASE_SSC->SSC_RFMR = SSC_FRAME_MODE_BITS_IN_WORD(16); // Setting Frame Mode For better performance on high speed data transfer.
 
        trigger_cnt = 0;
        uint16_t r = 0;
-       while(!BUTTON_PRESS()) {
+       while(!BUTTON_PRESS() && !usb_poll_validate_length() ) {
                WDT_HIT();
                if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
                        r = (uint16_t)AT91C_BASE_SSC->SSC_RHR;
-                       if (!(trigger_cnt == triggersToSkip) && ( (r >> 8) >= 240)) 
+                       r = MAX(r & 0xff, r >> 8); 
+                       if (r >= 240) 
                        {
-                               Dbprintf("Trigger kicked! Value: %d.", r >> 8);
-                               trigger_cnt++;
+                               
+                               if (++trigger_cnt > triggersToSkip) {
                                break;
                        } 
                }
        }
+       }
+
        if(!BUTTON_PRESS()) {
-               Dbprintf("Trigger kicked! Value: %d, Dumping Samples Hispeed now.", r >> 8);
                int waitcount = samplesToSkip; // lets wait 40000 ticks of pck0
                while(waitcount != 0) {
-                       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY)) {
-                               waitcount--;
-                       }
+                       
+                       if(AT91C_BASE_SSC->SSC_SR & (AT91C_SSC_RXRDY))
+                               --waitcount;
                }
                optimizedSnoop();
+               Dbprintf("Trigger kicked! Value: %d, Dumping Samples Hispeed now.", r);
        }
 
        DbpString("HF Snoop end");