]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - armsrc/legicrf.c
FIX: Coverity, logical vs bitwise operator, remove the extra '&' for it to become...
[proxmark3-svn] / armsrc / legicrf.c
index 3fbdf5cbaddaf6e6becd6ef1c4d8dd99056687e8..d9c94106e2f0fec21deede3e6d23fcd0e04455ad 100644 (file)
@@ -81,37 +81,39 @@ static void setup_timer(void)
 /* Generate Keystream */
 static uint32_t get_key_stream(int skip, int count)
 {
-  uint32_t key=0; int i;
-
-  /* Use int to enlarge timer tc to 32bit */
-  legic_prng_bc += prng_timer->TC_CV;
-  prng_timer->TC_CCR = AT91C_TC_SWTRG;
-
-  /* If skip == -1, forward prng time based */
-  if(skip == -1) {
-     i  = (legic_prng_bc+SIM_SHIFT)/SIM_DIVISOR; /* Calculate Cycles based on timer */
-     i -= legic_prng_count(); /* substract cycles of finished frames */
-     i -= count; /* substract current frame length, rewidn to bedinning */
-     legic_prng_forward(i);
-  } else {
-     legic_prng_forward(skip);
-  }
+       uint32_t key=0; int i;
+
+       /* Use int to enlarge timer tc to 32bit */
+       legic_prng_bc += prng_timer->TC_CV;
+       prng_timer->TC_CCR = AT91C_TC_SWTRG;
+
+       /* If skip == -1, forward prng time based */
+       if(skip == -1) {
+               i  = (legic_prng_bc+SIM_SHIFT)/SIM_DIVISOR; /* Calculate Cycles based on timer */
+               i -= legic_prng_count(); /* substract cycles of finished frames */
+               i -= count; /* substract current frame length, rewidn to bedinning */
+               legic_prng_forward(i);
+       } else {
+               legic_prng_forward(skip);
+       }
 
-  /* Write Time Data into LOG */
-  if(count == 6) { i = -1; } else { i = legic_read_count; }
-  ((uint8_t*)BigBuf)[OFFSET_LOG+128+i] = legic_prng_count();
-  ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4]   = (legic_prng_bc >> 0) & 0xff;
-  ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4+1] = (legic_prng_bc >> 8) & 0xff;
-  ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4+2] = (legic_prng_bc >>16) & 0xff;
-  ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4+3] = (legic_prng_bc >>24) & 0xff;
-  ((uint8_t*)BigBuf)[OFFSET_LOG+384+i] = count;
-
-  /* Generate KeyStream */
-  for(i=0; i<count; i++) {
-    key |= legic_prng_get_bit() << i;
-    legic_prng_forward(1);
-  }
-  return key;
+       /* Write Time Data into LOG */
+       uint8_t *BigBuf = BigBuf_get_addr();
+       i = (count == 6) ? -1 : legic_read_count;
+
+       BigBuf[OFFSET_LOG+128+i] = legic_prng_count();
+       BigBuf[OFFSET_LOG+256+i*4]   = (legic_prng_bc >> 0) & 0xff;
+       BigBuf[OFFSET_LOG+256+i*4+1] = (legic_prng_bc >> 8) & 0xff;
+       BigBuf[OFFSET_LOG+256+i*4+2] = (legic_prng_bc >>16) & 0xff;
+       BigBuf[OFFSET_LOG+256+i*4+3] = (legic_prng_bc >>24) & 0xff;
+       BigBuf[OFFSET_LOG+384+i] = count;
+
+       /* Generate KeyStream */
+       for(i=0; i<count; i++) {
+               key |= legic_prng_get_bit() << i;
+               legic_prng_forward(1);
+       }
+       return key;
 }
 
 /* Send a frame in tag mode, the FPGA must have been set up by
@@ -144,11 +146,11 @@ static void frame_send_tag(uint16_t response, int bits, int crypt)
       int nextbit = timer->TC_CV + TAG_TIME_BIT;
       int bit = response & 1;
       response = response >> 1;
-      if(bit) {
+      if(bit)
          AT91C_BASE_PIOA->PIO_SODR = GPIO_SSC_DOUT;
-      } else {
+      else
          AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
-      }
+      
       while(timer->TC_CV < nextbit) ;
    }
    AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
@@ -170,11 +172,11 @@ static void frame_send_rwd(uint32_t data, int bits)
                int bit = data & 1;
                data = data >> 1;
 
-               if(bit ^ legic_prng_get_bit()) {
+               if(bit ^ legic_prng_get_bit())
                        bit_end = starttime + RWD_TIME_1;
-               } else {
+               else
                        bit_end = starttime + RWD_TIME_0;
-               }
+               
 
                /* RWD_TIME_PAUSE time off, then some time on, so that the complete bit time is
                 * RWD_TIME_x, where x is the bit to be transmitted */
@@ -183,16 +185,15 @@ static void frame_send_rwd(uint32_t data, int bits)
                AT91C_BASE_PIOA->PIO_SODR = GPIO_SSC_DOUT;
                legic_prng_forward(1); /* bit duration is longest. use this time to forward the lfsr */
 
-               while(timer->TC_CV < bit_end) ;
+               while(timer->TC_CV < bit_end);
        }
 
-       {
-               /* One final pause to mark the end of the frame */
-               int pause_end = timer->TC_CV + RWD_TIME_PAUSE;
-               AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
-               while(timer->TC_CV < pause_end) ;
-               AT91C_BASE_PIOA->PIO_SODR = GPIO_SSC_DOUT;
-       }
+       /* One final pause to mark the end of the frame */
+       int pause_end = timer->TC_CV + RWD_TIME_PAUSE;
+       AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
+       while(timer->TC_CV < pause_end) ;
+       AT91C_BASE_PIOA->PIO_SODR = GPIO_SSC_DOUT;
+
 
        /* Reset the timer, to measure time until the start of the tag frame */
        timer->TC_CCR = AT91C_TC_SWTRG;
@@ -238,8 +239,7 @@ static void frame_receive_rwd(struct legic_frame * const f, int bits, int crypt)
      * since we cannot compute it on the fly while reading */
        legic_prng_forward(2);
 
-       if(crypt)
-       {
+       if(crypt) {
                for(i=0; i<bits; i++) {
                        data |= legic_prng_get_bit() << i;
                        legic_prng_forward(1);
@@ -276,9 +276,9 @@ static void frame_receive_rwd(struct legic_frame * const f, int bits, int crypt)
 
 static void frame_append_bit(struct legic_frame * const f, int bit)
 {
-   if(f->bits >= 31) {
+   if(f->bits >= 31)
        return; /* Overflow, won't happen */
-   }
+  
    f->data |= (bit<<f->bits);
    f->bits++;
 }
@@ -426,6 +426,7 @@ int LegicRfReader(int offset, int bytes) {
 
        LegicCommonInit();
 
+       uint8_t *BigBuf = BigBuf_get_addr();
        memset(BigBuf, 0, 1024);
 
        DbpString("setting up legic card");
@@ -446,12 +447,11 @@ int LegicRfReader(int offset, int bytes) {
                        Dbprintf("Unknown card format: %x",tag_type);
                        return -1;
        }
-       if(bytes == -1) {
+       if(bytes == -1)
                bytes = card_sz;
-       }
-       if(bytes+offset >= card_sz) {
+
+       if(bytes+offset >= card_sz)
                bytes = card_sz-offset;
-       }
 
        perform_setup_phase_rwd(SESSION_IV);
 
@@ -465,7 +465,7 @@ int LegicRfReader(int offset, int bytes) {
                        LED_C_OFF();
                return -1;
                }
-               ((uint8_t*)BigBuf)[byte_index] = r;
+               BigBuf[byte_index] = r;
         WDT_HIT();
                byte_index++;
                if(byte_index & 0x10) LED_C_ON(); else LED_C_OFF();
@@ -480,7 +480,8 @@ int LegicRfReader(int offset, int bytes) {
 
 void LegicRfWriter(int bytes, int offset) {
        int byte_index=0, addr_sz=0;
-       
+       uint8_t *BigBuf = BigBuf_get_addr();
+
        LegicCommonInit();
        
        DbpString("setting up legic card");
@@ -512,7 +513,7 @@ void LegicRfWriter(int bytes, int offset) {
        perform_setup_phase_rwd(SESSION_IV);
     legic_prng_forward(2);
        while(byte_index < bytes) {
-               int r = legic_write_byte(((uint8_t*)BigBuf)[byte_index+offset], byte_index+offset, addr_sz);
+               int r = legic_write_byte(BigBuf[byte_index+offset], byte_index+offset, addr_sz);
                if((r != 0) || BUTTON_PRESS()) {
                        Dbprintf("operation aborted @ 0x%03.3x", byte_index);
                        switch_off_tag_rwd();
@@ -534,6 +535,8 @@ int timestamp;
 /* Handle (whether to respond) a frame in tag mode */
 static void frame_handle_tag(struct legic_frame const * const f)
 {
+       uint8_t *BigBuf = BigBuf_get_addr();
+
    /* First Part of Handshake (IV) */
    if(f->bits == 7) {
      if(f->data == SESSION_IV) {
@@ -582,9 +585,9 @@ static void frame_handle_tag(struct legic_frame const * const f)
       if(legic_state == STATE_CON) {
          int key   = get_key_stream(-1, 11); //legic_phase_drift, 11);
          int addr  = f->data ^ key; addr = addr >> 1;
-         int data = ((uint8_t*)BigBuf)[addr];
+         int data = BigBuf[addr];
          int hash = LegicCRC(addr, data, 11) << 8;
-         ((uint8_t*)BigBuf)[OFFSET_LOG+legic_read_count] = (uint8_t)addr;
+         BigBuf[OFFSET_LOG+legic_read_count] = (uint8_t)addr;
          legic_read_count++;
 
          //Dbprintf("Data:%03.3x, key:%03.3x, addr: %03.3x, read_c:%u", f->data, key, addr, read_c);
@@ -619,19 +622,19 @@ static void frame_handle_tag(struct legic_frame const * const f)
       int i;
       Dbprintf("IV: %03.3x", legic_prng_iv);
       for(i = 0; i<legic_read_count; i++) {
-         Dbprintf("Read Nb: %u, Addr: %u", i, ((uint8_t*)BigBuf)[OFFSET_LOG+i]);
+         Dbprintf("Read Nb: %u, Addr: %u", i, BigBuf[OFFSET_LOG+i]);
       }
 
       for(i = -1; i<legic_read_count; i++) {
          uint32_t t;
-         t  = ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4];
-         t |= ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4+1] << 8;
-         t |= ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4+2] <<16;
-         t |= ((uint8_t*)BigBuf)[OFFSET_LOG+256+i*4+3] <<24;
+         t  = BigBuf[OFFSET_LOG+256+i*4];
+         t |= BigBuf[OFFSET_LOG+256+i*4+1] << 8;
+         t |= BigBuf[OFFSET_LOG+256+i*4+2] <<16;
+         t |= BigBuf[OFFSET_LOG+256+i*4+3] <<24;
 
          Dbprintf("Cycles: %u, Frame Length: %u, Time: %u", 
-            ((uint8_t*)BigBuf)[OFFSET_LOG+128+i],
-            ((uint8_t*)BigBuf)[OFFSET_LOG+384+i],
+            BigBuf[OFFSET_LOG+128+i],
+            BigBuf[OFFSET_LOG+384+i],
             t);
       }
    }
@@ -706,7 +709,7 @@ void LegicRfSimulate(int phase, int frame, int reqresp)
 
    LED_B_ON();
    DbpString("Starting Legic emulator, press button to end");
-   while(!BUTTON_PRESS()) {
+   while(!BUTTON_PRESS() && !usb_poll_validate_length()) {
       int level = !!(AT91C_BASE_PIOA->PIO_PDSR & GPIO_SSC_DIN);
       int time = timer->TC_CV;
                 
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