#include "rfid_iso14443_common.h"
+#define RFID_MAX_FRAMELEN 256
+
static enum rfid_frametype l2_to_frame(unsigned int layer2)
{
switch (layer2) {
#define is_r_block(x) ((x & 0xc0) == 0x80)
#define is_i_block(x) ((x & 0xc0) == 0x00)
+struct fr_buff {
+ unsigned int frame_len; /* length of frame */
+ unsigned int hdr_len; /* length of header within frame */
+ unsigned char data[RFID_MAX_FRAMELEN];
+};
+
+#define frb_payload(x) (x.data + x.hdr_len)
+
+
+/* RFID transceive buffer. */
+struct rfid_xcvb {
+ struct rfix_xcvb *next; /* next in queue of buffers */
+
+ u_int64_t timeout; /* timeout to wait for reply */
+ struct fr_buff tx;
+ struct fr_buff rx;
+
+ //struct rfid_protocol_handle *h; /* connection to which we belong */
+};
+
+struct tcl_tx_context {
+ const unsigned char *tx;
+ unsigned char *rx;
+ const unsigned char *next_tx_byte;
+ unsigned char *next_rx_byte;
+ unsigned int rx_len;
+ unsigned int tx_len;
+ struct rfid_protocol_handle *h;
+};
+
+#define tcl_ctx_todo(ctx) (ctx->tx_len - (ctx->next_tx_byte - ctx->tx))
+
+static int
+tcl_refill_xcvb(struct rfid_xcvb *xcvb, struct tcl_tx_context *ctx)
+{
+ struct tcl_handle *th = &ctx->h->priv.tcl;
+
+ if (ctx->next_tx_byte >= ctx->tx + ctx->tx_len) {
+ DEBUGP("tyring to refill tx xcvb but no data left!\n");
+ return -1;
+ }
+
+ if (tcl_build_prologue_i(th, xcvb->tx.data,
+ &xcvb->tx.hdr_len) < 0)
+ return -1;
+
+ if (tcl_ctx_todo(ctx) > th->fsc - xcvb->tx.hdr_len)
+ xcvb->tx.frame_len = max_net_tx_framesize(th);
+ else
+ xcvb->tx.frame_len = tcl_ctx_todo(ctx);
+
+ memcpy(frb_payload(xcvb->tx), ctx->next_tx_byte,
+ xcvb->tx.frame_len);
+
+ ctx->next_tx_byte += xcvb->tx.frame_len;
+
+ /* check whether we need to set the chaining bit */
+ if (ctx->next_tx_byte < ctx->tx + ctx->tx_len)
+ xcvb->tx.data[0] |= 0x10;
+
+ /* add hdr_len after copying the net payload */
+ xcvb->tx.frame_len += xcvb->tx.hdr_len;
+
+ xcvb->timeout = th->fwt;
+
+ return 0;
+}
+
+static void fill_xcvb_wtxm(struct tcl_handle *th, struct rfid_xcvb *xcvb,
+ unsigned char inf)
+{
+ /* Acknowledge WTXM */
+ tcl_build_prologue_s(th, xcvb->tx.data, &xcvb->tx.hdr_len);
+ /* set two bits that make this block a wtx */
+ xcvb->tx.data[0] |= 0x30;
+ xcvb->tx.data[xcvb->tx.hdr_len] = inf;
+ xcvb->tx.frame_len = xcvb->tx.hdr_len+1;
+ xcvb->timeout = th->fwt * inf;
+}
+
+static int check_cid(struct tcl_handle *th, struct rfid_xcvb *xcvb)
+{
+ if (xcvb->rx.data[0] & TCL_PCB_CID_FOLLOWING) {
+ if (xcvb->rx.data[1] != th->cid) {
+ DEBUGP("CID %u is not valid, we expected %u\n",
+ xcvb->rx.data[1], th->cid);
+ return 0;
+ }
+ }
+ return 1;
+}
+
static int
tcl_transceive(struct rfid_protocol_handle *h,
const unsigned char *tx_data, unsigned int tx_len,
unsigned int timeout, unsigned int flags)
{
int ret;
- unsigned char *tx_buf, *rx_buf;
- unsigned char *_rx_data = rx_data;
- unsigned int _rx_len;
- unsigned int max_rx_len = *rx_len; /* maximum number of payoload that
- caller has requested */
- unsigned int prlg_len;
+
+ struct rfid_xcvb xcvb;
+ struct tcl_tx_context tcl_ctx;
struct tcl_handle *th = &h->priv.tcl;
- unsigned char *_tx;
- unsigned int _tx_len, _timeout;
- unsigned char wtx_resp[3];
unsigned char ack[10];
unsigned int ack_len;
- tx_buf = malloc(tcl_prlg_len(th) + tx_len);
- if (!tx_buf) {
- ret = -ENOMEM;
- goto out;
- }
- rx_buf = malloc(tcl_prlg_len(th) + *rx_len);
- if (!rx_buf) {
- ret = -ENOMEM;
- goto out_txb;
- }
-
- if (tcl_build_prologue_i(th, tx_buf, &prlg_len) < 0) {
- ret = -1;
- goto out_rxb;
- }
- memcpy(tx_buf + prlg_len, tx_data, tx_len);
-
- /* intialize to data-to-be-transferred */
- _tx = tx_buf;
- _tx_len = tx_len+prlg_len;
- _timeout = th->fwt;
- _rx_len = *rx_len;
- *rx_len = 0;
+ /* initialize context */
+ tcl_ctx.next_tx_byte = tcl_ctx.tx = tx_data;
+ tcl_ctx.next_rx_byte = tcl_ctx.rx = rx_data;
+ tcl_ctx.rx_len = *rx_len;
+ tcl_ctx.tx_len = tx_len;
+ tcl_ctx.h = h;
+ /* initialize xcvb */
+ xcvb.timeout = th->fwt;
- if (_tx_len > max_net_tx_framesize(th)+prlg_len) {
- /* slow path: we need to use chaining */
- _tx_len = max_net_tx_framesize(th)+prlg_len;
+tx_refill:
+ if (tcl_refill_xcvb(&xcvb, &tcl_ctx) < 0) {
+ ret = -1;
+ goto out;
}
do_tx:
+ xcvb.rx.frame_len = sizeof(xcvb.rx.data);
ret = rfid_layer2_transceive(h->l2h, l2_to_frame(h->l2h->l2->id),
- _tx, _tx_len,
- rx_buf, &_rx_len, _timeout, 0);
+ xcvb.tx.data, xcvb.tx.frame_len,
+ xcvb.rx.data, &xcvb.rx.frame_len,
+ xcvb.timeout, 0);
+
DEBUGP("l2 transceive finished\n");
if (ret < 0)
- goto out_rxb;
+ goto out;
- if ((*rx_buf & 0x01) != h->priv.tcl.toggle) {
+ if ((xcvb.rx.data[0] & 0x01) != h->priv.tcl.toggle) {
DEBUGP("response with wrong toggle bit\n");
- goto out_rxb;
+ goto out;
}
- if (is_r_block(*rx_buf)) {
- unsigned int txed = _tx - tx_buf;
+ if (is_r_block(xcvb.rx.data[0])) {
DEBUGP("R-Block\n");
+
/* Handle ACK frame in case of chaining */
- if (*rx_buf & TCL_PCB_CID_FOLLOWING) {
- if (*(rx_buf+1) != h->priv.tcl.cid) {
- DEBUGP("CID %u is not valid\n", *(rx_buf)+1);
- goto out_rxb;
- }
- }
- /* set up parameters for next frame in chain */
- if (txed < tx_len) {
- /* move tx pointer by the amount of bytes transferred
- * in last frame */
- _tx += _tx_len;
- _tx_len = (tx_len - txed);
- if (_tx_len > max_net_tx_framesize(th)) {
- /* not last frame in chain */
- _tx_len = max_net_tx_framesize(th);
- } else {
- /* last frame in chain */
- }
- goto do_tx;
- } else {
- DEBUGP("Received ACK in response to last frame in "
- "chain?!? Expected I-frame.\n");
- ret = -1;
- goto out_rxb;
- }
- } else if (is_s_block(*rx_buf)) {
+ if (!check_cid(th, &xcvb))
+ goto out;
+
+ goto tx_refill;
+ } else if (is_s_block(xcvb.rx.data[0])) {
unsigned char inf;
unsigned int prlg_len;
DEBUGP("S-Block\n");
/* Handle Wait Time Extension */
- if (*rx_buf & TCL_PCB_CID_FOLLOWING) {
- if (_rx_len < 3) {
+
+ if (!check_cid(th, &xcvb))
+ goto out;
+
+ if (xcvb.rx.data[0] & TCL_PCB_CID_FOLLOWING) {
+ if (xcvb.rx.frame_len < 3) {
DEBUGP("S-Block with CID but short len\n");
ret = -1;
- goto out_rxb;
+ goto out;
}
- if (*(rx_buf+1) != h->priv.tcl.cid) {
- DEBUGP("CID %u is not valid\n", *(rx_buf)+1);
- goto out_rxb;
- }
- inf = *(rx_buf+2);
+ inf = xcvb.rx.data[2];
} else
- inf = *(rx_buf+1);
+ inf = xcvb.rx.data[1];
- if ((*rx_buf & 0x30) != 0x30) {
+ if ((xcvb.rx.data[0] & 0x30) != 0x30) {
DEBUGP("S-Block but not WTX?\n");
ret = -1;
- goto out_rxb;
+ goto out;
}
inf &= 0x3f; /* only lower 6 bits code WTXM */
if (inf == 0 || (inf >= 60 && inf <= 63)) {
DEBUGP("WTXM %u is RFU!\n", inf);
ret = -1;
- goto out_rxb;
+ goto out;
}
- /* Acknowledge WTXM */
- tcl_build_prologue_s(&h->priv.tcl, wtx_resp, &prlg_len);
- /* set two bits that make this block a wtx */
- wtx_resp[0] |= 0x30;
- wtx_resp[prlg_len] = inf;
- _tx = wtx_resp;
- _tx_len = prlg_len+1;
- _timeout = th->fwt * inf;
-
+ fill_xcvb_wtxm(th, &xcvb, inf);
/* start over with next transceive */
- goto do_tx; /* FIXME: do transceive locally since we use
- totally different buffer */
-
- } else if (is_i_block(*rx_buf)) {
- unsigned char *inf = rx_buf+1;
+ goto do_tx;
+ } else if (is_i_block(xcvb.rx.data[0])) {
unsigned int net_payload_len;
/* we're actually receiving payload data */
DEBUGP("I-Block: ");
- if (*rx_buf & TCL_PCB_CID_FOLLOWING) {
- if (*(rx_buf+1) != h->priv.tcl.cid) {
- DEBUGPC("CID %u is not valid\n", *(rx_buf)+1);
- goto out_rxb;
- }
- inf++;
- }
- if (*rx_buf & TCL_PCB_NAD_FOLLOWING) {
- inf++;
- }
- net_payload_len = _rx_len - (inf - rx_buf);
+ xcvb.rx.hdr_len = 1;
+
+ if (!check_cid(th, &xcvb))
+ goto out;
+
+ if (xcvb.rx.data[0] & TCL_PCB_CID_FOLLOWING)
+ xcvb.rx.hdr_len++;
+ if (xcvb.rx.data[0] & TCL_PCB_NAD_FOLLOWING)
+ xcvb.rx.hdr_len++;
+
+ net_payload_len = xcvb.rx.frame_len - xcvb.rx.hdr_len;
DEBUGPC("%u bytes\n", net_payload_len);
- memcpy(_rx_data, inf, net_payload_len);
- /* increment the number of payload bytes that we actually
- * received */
- *rx_len += net_payload_len;
- _rx_data += net_payload_len;
+ memcpy(tcl_ctx.next_rx_byte, &xcvb.rx.data[xcvb.rx.hdr_len],
+ net_payload_len);
+ tcl_ctx.next_rx_byte += net_payload_len;
- if (*rx_buf & 0x10) {
+ if (xcvb.rx.data[0] & 0x10) {
/* we're not the last frame in the chain, continue rx */
DEBUGP("not the last frame in the chain, continue\n");
ack_len = sizeof(ack);
- tcl_build_prologue_r(&h->priv.tcl, ack, &ack_len, 0);
- _tx = ack;
- _tx_len = ack_len;
+ tcl_build_prologue_r(th, xcvb.tx.data, &xcvb.tx.frame_len, 0);
+ xcvb.timeout = th->fwt;
goto do_tx;
}
}
-out_rxb:
- free(rx_buf);
-out_txb:
- free(tx_buf);
out:
+ *rx_len = tcl_ctx.next_rx_byte - tcl_ctx.rx;
return ret;
}
projects / librfid / commitdiff