diff options
| -rw-r--r-- | src/rfid_proto_tcl.c | 275 |
1 files changed, 157 insertions, 118 deletions
diff --git a/src/rfid_proto_tcl.c b/src/rfid_proto_tcl.c index afcfb36..64f28b3 100644 --- a/src/rfid_proto_tcl.c +++ b/src/rfid_proto_tcl.c @@ -36,6 +36,8 @@ #include "rfid_iso14443_common.h" +#define RFID_MAX_FRAMELEN 256 + static enum rfid_frametype l2_to_frame(unsigned int layer2) { switch (layer2) { @@ -498,6 +500,98 @@ tcl_deselect(struct rfid_protocol_handle *h) #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, @@ -505,177 +599,122 @@ tcl_transceive(struct rfid_protocol_handle *h, 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; } |