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authormeri <meri@e0336214-984f-0b4b-a45f-81c69e1f0ede>2007-04-25 01:36:28 +0000
committermeri <meri@e0336214-984f-0b4b-a45f-81c69e1f0ede>2007-04-25 01:36:28 +0000
commitda107e125605438c7cf739ad34bb6204b3d4b85e (patch)
tree159fb26ca042567685e5ea94ae0bf49f75340714 /src
parent8a68898b0790c7cfc6f88caadd2209831f2be81c (diff)
fixed ISO 14443A anticollision
git-svn-id: https://svn.gnumonks.org/trunk/librfid@1988 e0336214-984f-0b4b-a45f-81c69e1f0ede
Diffstat (limited to 'src')
-rw-r--r--src/rfid_asic_rc632.c20
-rw-r--r--src/rfid_layer2_iso14443a.c52
2 files changed, 49 insertions, 23 deletions
diff --git a/src/rfid_asic_rc632.c b/src/rfid_asic_rc632.c
index 0d6824c..0560d09 100644
--- a/src/rfid_asic_rc632.c
+++ b/src/rfid_asic_rc632.c
@@ -875,7 +875,7 @@ rc632_iso14443a_transceive_acf(struct rfid_asic_handle *handle,
int ret;
u_int8_t rx_buf[64];
u_int8_t rx_len = sizeof(rx_buf);
- u_int8_t rx_align = 0, tx_last_bits, tx_bytes;
+ u_int8_t rx_align = 0, tx_last_bits, tx_bytes, tx_bytes_total;
u_int8_t boc;
u_int8_t error_flag;
*bit_of_col = ISO14443A_BITOFCOL_NONE;
@@ -899,14 +899,14 @@ rc632_iso14443a_transceive_acf(struct rfid_asic_handle *handle,
if (ret < 0)
return ret;
- tx_last_bits = acf->nvb & 0x0f; /* lower nibble indicates bits */
- tx_bytes = acf->nvb >> 4;
+ tx_last_bits = acf->nvb & 0x07; /* lower nibble indicates bits */
+ tx_bytes = ( acf->nvb >> 4 ) & 0x07;
if (tx_last_bits) {
- tx_bytes++;
- rx_align = (tx_last_bits+1) % 8;/* rx frame complements tx */
+ tx_bytes_total = tx_bytes+1;
+ rx_align = tx_last_bits & 0x07; /* rx frame complements tx */
}
-
- //rx_align = 8 - tx_last_bits;/* rx frame complements tx */
+ else
+ tx_bytes_total = tx_bytes;
/* set RxAlign and TxLastBits*/
ret = rc632_reg_write(handle, RC632_REG_BIT_FRAMING,
@@ -914,7 +914,7 @@ rc632_iso14443a_transceive_acf(struct rfid_asic_handle *handle,
if (ret < 0)
return ret;
- ret = rc632_transceive(handle, (u_int8_t *)acf, tx_bytes,
+ ret = rc632_transceive(handle, (u_int8_t *)acf, tx_bytes_total,
rx_buf, &rx_len, 0x32, 0);
if (ret < 0)
return ret;
@@ -923,8 +923,10 @@ rc632_iso14443a_transceive_acf(struct rfid_asic_handle *handle,
acf->uid_bits[tx_bytes-2] = (
(acf->uid_bits[tx_bytes-2] & (0xff >> (8-tx_last_bits)))
| rx_buf[0]);
+
/* copy the rest */
- memcpy(&acf->uid_bits[tx_bytes+1-2], &rx_buf[1], rx_len-1);
+ if(rx_len)
+ memcpy(&acf->uid_bits[tx_bytes-1], &rx_buf[1], rx_len-1);
/* determine whether there was a collission */
ret = rc632_reg_read(handle, RC632_REG_ERROR_FLAG, &error_flag);
diff --git a/src/rfid_layer2_iso14443a.c b/src/rfid_layer2_iso14443a.c
index 4716018..2c4cb1e 100644
--- a/src/rfid_layer2_iso14443a.c
+++ b/src/rfid_layer2_iso14443a.c
@@ -23,6 +23,8 @@
#include <unistd.h>
#include <string.h>
#include <errno.h>
+
+// #define DEBUG_LIBRFID
#include <librfid/rfid.h>
#include <librfid/rfid_layer2.h>
@@ -32,6 +34,8 @@
#define TIMEOUT 1236
+unsigned long randctx[4]={0x22d4a017,0x773a1f44,0xc39e1460,0x9cde8801};
+
/* Transceive a 7-bit short frame */
int
iso14443a_transceive_sf(struct rfid_layer2_handle *handle,
@@ -80,20 +84,38 @@ iso14443a_code_nvb_bits(unsigned char *nvb, unsigned int bits)
return 0;
}
+int random_bit(void)
+{
+ unsigned long e;
+
+ e = randctx[0];
+ randctx[0]=randctx[1];
+ randctx[1]=(randctx[2]<<19) + (randctx[2]>>13) + randctx[3];
+ randctx[2]=randctx[3] ^ randctx[0];
+ randctx[3]=e+randctx[1];
+
+ return randctx[1]&1;
+}
+
/* first bit is '1', second bit '2' */
static void
-set_bit_in_field(unsigned char *bitfield, unsigned int bit)
+rnd_toggle_bit_in_field(unsigned char *bitfield, unsigned int size, unsigned int bit)
{
- unsigned int byte_count = bit / 8;
- unsigned int bit_count = bit % 8;
-
- DEBUGP("bitfield=%p, byte_count=%u, bit_count=%u\n",
- bitfield, byte_count, bit_count);
- DEBUGP("%p = 0x%02x\n", (bitfield+byte_count), *(bitfield+byte_count));
- *(bitfield+byte_count) |= 1 << (bit_count-1);
- DEBUGP("%p = 0x%02x\n", (bitfield+byte_count), *(bitfield+byte_count));
+ unsigned int byte,rnd;
+
+ if(bit && (bit <= (size*8)) )
+ {
+ rnd=random_bit();
+
+ DEBUGP("xor'ing bit %u with %u\n",bit,rnd);
+ bit--;
+ byte=bit/8;
+ bit=rnd<<(bit%8);
+ bitfield[byte] ^= bit;
+ }
}
+
static int
iso14443a_anticol(struct rfid_layer2_handle *handle)
{
@@ -122,7 +144,7 @@ iso14443a_anticol(struct rfid_layer2_handle *handle)
return ret;
}
h->state = ISO14443A_STATE_ATQA_RCVD;
-
+
DEBUGP("ATQA: 0x%02x 0x%02x\n", *aqptr, *(aqptr+1));
if (!atqa->bf_anticol) {
@@ -150,18 +172,20 @@ cascade:
ret = iso14443a_transceive_acf(handle, &acf, &bit_of_col);
if (ret < 0)
return ret;
- DEBUGP("bit_of_col = %u\n", bit_of_col);
while (bit_of_col != ISO14443A_BITOFCOL_NONE) {
- set_bit_in_field(&acf.uid_bits[0], bit_of_col-16);
+ DEBUGP("collision at pos %u\n", bit_of_col);
+
iso14443a_code_nvb_bits(&acf.nvb, bit_of_col);
+ rnd_toggle_bit_in_field(acf.uid_bits, sizeof(acf.uid_bits), bit_of_col);
+ DEBUGP("acf: nvb=0x%02X uid_bits=%s\n",acf.nvb,rfid_hexdump(acf.uid_bits,sizeof(acf.uid_bits)));
ret = iso14443a_transceive_acf(handle, &acf, &bit_of_col);
- DEBUGP("bit_of_col = %u\n", bit_of_col);
if (ret < 0)
return ret;
}
iso14443a_code_nvb_bits(&acf.nvb, 7*8);
+
ret = iso14443a_transceive(handle, RFID_14443A_FRAME_REGULAR,
(unsigned char *)&acf, 7,
(unsigned char *) &sak, &rx_len,
@@ -325,7 +349,7 @@ iso14443a_init(struct rfid_reader_handle *rh)
return NULL;
memset(h, 0, sizeof(*h));
-
+
h->l2 = &rfid_layer2_iso14443a;
h->rh = rh;
h->priv.iso14443a.state = ISO14443A_STATE_NONE;
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