-/*
- * LEGIC RF simulation code
- *
- * (c) 2009 Henryk Plötz <henryk@ploetzli.ch>
- */
-
-#include <proxmark3.h>
-
+//-----------------------------------------------------------------------------
+// (c) 2009 Henryk Plötz <henryk@ploetzli.ch>
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// LEGIC RF simulation code
+//-----------------------------------------------------------------------------
+
+#include "proxmark3.h"
#include "apps.h"
-#include "legicrf.h"
-#include "unistd.h"
-#include "stdint.h"
+#include "util.h"
+#include "string.h"
+#include "legicrf.h"
#include "legic_prng.h"
#include "crc.h"
static struct legic_frame {
int bits;
- uint16_t data;
+ uint32_t data;
} current_frame;
static crc_t legic_crc;
/* Start clock */
timer->TC_CCR = AT91C_TC_CLKEN | AT91C_TC_SWTRG;
while(timer->TC_CV > 1) ; /* Wait till the clock has reset */
-
+
int i;
for(i=0; i<bits; i++) {
int starttime = timer->TC_CV;
} 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 */
AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
while(timer->TC_CV < pause_end) ;
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) ;
}
-
+
{
/* One final pause to mark the end of the frame */
int pause_end = timer->TC_CV + RWD_TIME_PAUSE;
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;
while(timer->TC_CV > 1) ; /* Wait till the clock has reset */
/* Receive a frame from the card in reader emulation mode, the FPGA and
* timer must have been set up by LegicRfReader and frame_send_rwd.
- *
+ *
* The LEGIC RF protocol from card to reader does not include explicit
* frame start/stop information or length information. The reader must
* know beforehand how many bits it wants to receive. (Notably: a card
* sending a stream of 0-bits is indistinguishable from no card present.)
- *
+ *
* Receive methodology: There is a fancy correlator in hi_read_rx_xcorr, but
* I'm not smart enough to use it. Instead I have patched hi_read_tx to output
* the ADC signal with hysteresis on SSP_DIN. Bit-bang that signal and look
* expected for a 212kHz subcarrier, this was a 1-bit. For timing we use the
* timer that's still running from frame_send_rwd in order to get a synchronization
* with the frame that we just sent.
- *
- * FIXME: Because we're relying on the hysteresis to just do the right thing
+ *
+ * FIXME: Because we're relying on the hysteresis to just do the right thing
* the range is severely reduced (and you'll probably also need a good antenna).
- * So this should be fixed some time in the future for a proper receiver.
+ * So this should be fixed some time in the future for a proper receiver.
*/
static void frame_receive_rwd(struct legic_frame * const f, int bits, int crypt)
{
- uint16_t the_bit = 1; /* Use a bitmask to save on shifts */
- uint16_t data=0;
+ uint32_t the_bit = 1; /* Use a bitmask to save on shifts */
+ uint32_t data=0;
int i, old_level=0, edges=0;
int next_bit_at = TAG_TIME_WAIT;
-
-
+
+
if(bits > 16)
bits = 16;
while(timer->TC_CV < next_bit_at) ;
next_bit_at += TAG_TIME_BIT;
-
+
for(i=0; i<bits; i++) {
edges = 0;
old_level = level;
}
next_bit_at += TAG_TIME_BIT;
-
+
if(edges > 20 && edges < 60) { /* expected are 42 edges */
data ^= the_bit;
}
the_bit <<= 1;
}
-
+
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 */
f->bits = 0;
}
-static uint16_t perform_setup_phase_rwd(int iv)
+static uint32_t perform_setup_phase_rwd(int iv)
{
-
+
/* Switch on carrier and let the tag charge for 1ms */
AT91C_BASE_PIOA->PIO_SODR = GPIO_SSC_DOUT;
SpinDelay(1);
-
+
legic_prng_init(0); /* no keystream yet */
frame_send_rwd(iv, 7);
legic_prng_init(iv);
-
+
frame_clean(¤t_frame);
frame_receive_rwd(¤t_frame, 6, 1);
legic_prng_forward(1); /* we wait anyways */
while(timer->TC_CV < 387) ; /* ~ 258us */
frame_send_rwd(0x19, 6);
- if(current_frame.data != 0x1d)
- Dbprintf("probably don't know how to deal with %x card", current_frame.data);
return current_frame.data;
}
SetAdcMuxFor(GPIO_MUXSEL_HIPKD);
FpgaSetupSsc();
FpgaWriteConfWord(FPGA_MAJOR_MODE_HF_READER_TX);
-
+
/* Bitbang the transmitter */
AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
AT91C_BASE_PIOA->PIO_OER = GPIO_SSC_DOUT;
AT91C_BASE_PIOA->PIO_PER = GPIO_SSC_DOUT;
-
+
setup_timer();
-
+
crc_init(&legic_crc, 4, 0x19 >> 1, 0x5, 0);
}
/* Switch off carrier, make sure tag is reset */
AT91C_BASE_PIOA->PIO_CODR = GPIO_SSC_DOUT;
SpinDelay(10);
-
+
WDT_HIT();
}
/* calculate crc for a legic command */
-static int LegicCRC(int byte_index, int value) {
+static int LegicCRC(int byte_index, int value, int cmd_sz) {
crc_clear(&legic_crc);
crc_update(&legic_crc, 1, 1); /* CMD_READ */
- crc_update(&legic_crc, byte_index, 8);
+ crc_update(&legic_crc, byte_index, cmd_sz-1);
crc_update(&legic_crc, value, 8);
return crc_finish(&legic_crc);
}
-int legic_read_byte(int byte_index) {
+int legic_read_byte(int byte_index, int cmd_sz) {
int byte;
legic_prng_forward(4); /* we wait anyways */
while(timer->TC_CV < 387) ; /* ~ 258us + 100us*delay */
- frame_send_rwd(1 | (byte_index << 1), 9);
+ frame_send_rwd(1 | (byte_index << 1), cmd_sz);
frame_clean(¤t_frame);
frame_receive_rwd(¤t_frame, 12, 1);
byte = current_frame.data & 0xff;
- if( LegicCRC(byte_index, byte) != (current_frame.data >> 8) )
- Dbprintf("!!! crc mismatch: expected %x but got %x !!!", LegicCRC(byte_index, current_frame.data & 0xff), current_frame.data >> 8);
+ if( LegicCRC(byte_index, byte, cmd_sz) != (current_frame.data >> 8) ) {
+ Dbprintf("!!! crc mismatch: expected %x but got %x !!!", LegicCRC(byte_index, current_frame.data & 0xff, cmd_sz), current_frame.data >> 8);
+ return -1;
+ }
return byte;
}
void LegicRfReader(int offset, int bytes) {
- int byte_index=0;
-
+ int byte_index=0, cmd_sz=0, card_sz=0;
+
LegicCommonInit();
- memset(BigBuf, 0, 256);
-
+ memset(BigBuf, 0, 1024);
+
DbpString("setting up legic card");
+ uint32_t tag_type = perform_setup_phase_rwd(0x55);
+ switch(tag_type) {
+ case 0x1d:
+ DbpString("MIM 256 card found, reading card ...");
+ cmd_sz = 9;
+ card_sz = 256;
+ break;
+ case 0x3d:
+ DbpString("MIM 1024 card found, reading card ...");
+ cmd_sz = 11;
+ card_sz = 1024;
+ break;
+ default:
+ Dbprintf("Unknown card format: %x",tag_type);
+ switch_off_tag_rwd();
+ return;
+ }
+ if(bytes == -1) {
+ bytes = card_sz;
+ }
+ if(bytes+offset >= card_sz) {
+ bytes = card_sz-offset;
+ }
+
+ switch_off_tag_rwd(); //we lost to mutch time with dprintf
perform_setup_phase_rwd(0x55);
while(byte_index < bytes) {
- ((uint8_t*)BigBuf)[byte_index] = legic_read_byte(byte_index+offset);
+ int r = legic_read_byte(byte_index+offset, cmd_sz);
+ if(r == -1) {
+ Dbprintf("aborting");
+ switch_off_tag_rwd();
+ return;
+ }
+ ((uint8_t*)BigBuf)[byte_index] = r;
byte_index++;
}
switch_off_tag_rwd();
- Dbprintf("Card read, use 'data hexsamples %d' to view results", (bytes+7) & ~7);
+ Dbprintf("Card read, use 'hf legic decode' or 'data hexsamples %d' to view results", (bytes+7) & ~7);
}
+
projects / proxmark3-svn / blobdiff