/* ISO 14443-4 (T=CL) implementation, PCD side. * * (C) 2005 by Harald Welte * */ /* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include #include #include #include #include #include #include #include #include "rfid_iso14443_common.h" static enum rfid_frametype l2_to_frame(unsigned int layer2) { switch (layer2) { case RFID_LAYER2_ISO14443A: return RFID_14443A_FRAME_REGULAR; break; case RFID_LAYER2_ISO14443B: return RFID_14443B_FRAME_REGULAR; break; } return 0; } static unsigned int sfgi_to_sfgt(struct rfid_protocol_handle *h, unsigned char sfgi) { unsigned int multiplier; unsigned int tmp; if (sfgi > 14) sfgi = 14; multiplier = 1 << sfgi; /* 2 to the power of sfgi */ /* ISO 14443-4:2000(E) Section 5.2.5: * (256 * 16 / h->l2h->rh->ah->fc) * (2 ^ sfgi) */ tmp = (unsigned int) 1000000 * 256 * 16; return (tmp / h->l2h->rh->ah->fc) * multiplier; } static unsigned int fwi_to_fwt(struct rfid_protocol_handle *h, unsigned char fwi) { unsigned int multiplier, tmp; if (fwi > 14) fwi = 14; multiplier = 1 << fwi; /* 2 to the power of fwi */ /* ISO 14443-4:2000(E) Section 7.2.: * (256*16 / h->l2h->rh->ah->fc) * (2 ^ fwi) */ tmp = (unsigned int) 1000000 * 256 * 16; return (tmp / h->l2h->rh->ah->fc) * multiplier; } /* 4.9seconds as microseconds (4.9 billion seconds) exceeds 2^32 */ #define activation_fwt(x) (((u_int64_t)1000000 * 65536 / x->l2h->rh->ah->fc)) #define deactivation_fwt(x) activation_fwt(x) static int tcl_parse_ats(struct rfid_protocol_handle *h, unsigned char *ats, unsigned int size) { unsigned char len = ats[0]; unsigned char t0; unsigned char *cur; if (len == 0 || size == 0) return -1; if (size < len) len = size; h->priv.tcl.ta = 0; if (len == 1) { /* FIXME: assume some default values */ h->priv.tcl.fsc = 32; h->priv.tcl.ta = 0x80; /* 0x80 (same d for both dirs) */ h->priv.tcl.sfgt = sfgi_to_sfgt(h, 0); if (h->l2h->l2->id == RFID_LAYER2_ISO14443A) { /* Section 7.2: fwi default for type A is 4 */ h->priv.tcl.fwt = fwi_to_fwt(h, 4); } else { /* Section 7.2: fwi for type B is always in ATQB */ /* Value is assigned in tcl_connect() */ /* This function is never called for Type B, since it has no (R)ATS */ } return 0; } /* guarateed to be at least 2 bytes in size */ t0 = ats[1]; cur = &ats[2]; iso14443_fsdi_to_fsd(&h->priv.tcl.fsc, t0 & 0x0f); if (t0 & (1 << 4)) { /* TA is transmitted */ h->priv.tcl.ta = *cur++; } if (t0 & (1 << 5)) { /* TB is transmitted */ h->priv.tcl.sfgt = sfgi_to_sfgt(h, *cur & 0x0f); h->priv.tcl.fwt = fwi_to_fwt(h, (*cur & 0xf0) >> 4); cur++; } if (t0 & (1 << 6)) { /* TC is transmitted */ if (*cur & 0x01) h->priv.tcl.flags |= TCL_HANDLE_F_NAD_SUPPORTED; if (*cur & 0x02) h->priv.tcl.flags |= TCL_HANDLE_F_CID_SUPPORTED; cur++; } h->priv.tcl.historical_len = (ats+len) - cur; h->priv.tcl.historical_bytes = cur; return 0; } /* request an ATS from the PICC */ static int tcl_request_ats(struct rfid_protocol_handle *h) { int ret; unsigned char rats[2]; unsigned char fsdi; if (h->priv.tcl.state != TCL_STATE_INITIAL) return -1; ret = iso14443_fsd_to_fsdi(&fsdi, h->priv.tcl.fsd); if (ret < 0) { DEBUGP("unable to encode FSD of %u as FSDI\n", h->priv.tcl.fsd); return ret; } rats[0] = 0xe0; rats[1] = (h->priv.tcl.cid & 0x0f) | ((fsdi << 4) & 0xf0); /* transcieve (with CRC) */ ret = h->l2h->l2->fn.transcieve(h->l2h, RFID_14443A_FRAME_REGULAR, rats, 2, h->priv.tcl.ats, &h->priv.tcl.ats_len, activation_fwt(h), TCL_TRANSP_F_TX_CRC); if (ret < 0) { DEBUGP("transcieve of rats failed\n"); h->priv.tcl.state = TCL_STATE_RATS_SENT; /* FIXME: retransmit */ return ret; } h->priv.tcl.state = TCL_STATE_ATS_RCVD; ret = tcl_parse_ats(h, h->priv.tcl.ats, h->priv.tcl.ats_len); if (ret < 0) { DEBUGP("parsing of ats failed\n"); return ret; } return 0; } #define ATS_TA_DIV_2 1 #define ATS_TA_DIV_4 2 #define ATS_TA_DIV_8 4 #define PPS_DIV_8 3 #define PPS_DIV_4 2 #define PPS_DIV_2 1 #define PPS_DIV_1 0 static unsigned char d_to_di(struct rfid_protocol_handle *h, unsigned char D) { static char DI; unsigned int speed = h->l2h->rh->reader->iso14443a.speed; if ((D & ATS_TA_DIV_8) && (speed & RFID_READER_SPEED_848K)) DI = PPS_DIV_8; else if ((D & ATS_TA_DIV_4) && (speed & RFID_READER_SPEED_424K)) DI = PPS_DIV_4; else if ((D & ATS_TA_DIV_2) && (speed & RFID_READER_SPEED_212K)) DI = PPS_DIV_2; else DI = PPS_DIV_1; return DI; } /* start a PSS run (autimatically configure highest possible speed */ static int tcl_do_pps(struct rfid_protocol_handle *h) { #if 0 int ret; unsigned char ppss[3]; unsigned char pps_response[1]; unsigned int rx_len = 1; unsigned char Dr, Ds, DrI, DsI; if (h->priv.tcl.state != TCL_STATE_ATS_RCVD) return -1; Dr = h->priv.tcl.ta & 0x07; Ds = h->priv.tcl.ta & 0x70 >> 4; if (Dr != Ds && !(h->priv.tcl.ta & 0x80)) { /* device supports different divisors for rx and tx, but not ?!? */ DEBUGP("PICC has contradictory TA, aborting PPS\n"); return -1; }; /* ISO 14443-4:2000(E) Section 5.3. */ ppss[0] = 0xd0 & (h->priv.tcl.cid & 0x0f); ppss[1] = 0x11; /* FIXME: deal with different speed for each direction */ DrI = d_to_di(h, Dr); DsI = d_to_di(h, Ds); ppss[2] = (ppss[2] & 0xf0) | (DrI | DsI << 2); ret = h->l2h->l2->fn.transcieve(h->l2h, ppss, 3, pps_response, &rx_len, h->priv.tcl.fwt, TCL_TRANSP_F_TX_CRC); if (ret < 0) return ret; if (pps_response[0] != ppss[0]) { DEBUGP("PPS Response != PPSS\n"); return -1; } h->priv.tcl.state = TCL_STATE_ESTABLISHED; #endif return 0; } static int tcl_build_prologue2(struct tcl_handle *th, unsigned char *prlg, unsigned int *prlg_len, unsigned char pcb) { *prlg_len = 1; *prlg = pcb; if (th->toggle) { /* we've sent a toggle bit last time */ th->toggle = 0; } else { /* we've not sent a toggle last time: send one */ th->toggle = 1; *prlg |= 0x01; } if (th->flags & TCL_HANDLE_F_CID_USED) { /* ISO 14443-4:2000(E) Section 7.1.1.2 */ *prlg |= TCL_PCB_CID_FOLLOWING; (*prlg_len)++; prlg[*prlg_len] = th->cid & 0x0f; } /* nad only for I-block (0xc0 == 00) */ if ((th->flags & TCL_HANDLE_F_NAD_USED) && ((pcb & 0xc0) == 0x00)) { /* ISO 14443-4:2000(E) Section 7.1.1.3 */ /* FIXME: in case of chaining only for first frame */ *prlg |= TCL_PCB_NAD_FOLLOWING; prlg[*prlg_len] = th->nad; (*prlg_len)++; } return 0; } static int tcl_build_prologue_i(struct tcl_handle *th, unsigned char *prlg, unsigned int *prlg_len) { /* ISO 14443-4:2000(E) Section 7.1.1.1 */ return tcl_build_prologue2(th, prlg, prlg_len, 0x02); } static int tcl_build_prologue_r(struct tcl_handle *th, unsigned char *prlg, unsigned int *prlg_len, unsigned int nak) { unsigned char pcb = 0xa2; /* ISO 14443-4:2000(E) Section 7.1.1.1 */ if (nak) pcb |= 0x10; return tcl_build_prologue2(th, prlg, prlg_len, pcb); } static int tcl_build_prologue_s(struct tcl_handle *th, unsigned char *prlg, unsigned int *prlg_len) { /* ISO 14443-4:2000(E) Section 7.1.1.1 */ /* the only S-block from PCD->PICC is DESELECT, * well, actually there is the S(WTX) response. */ return tcl_build_prologue2(th, prlg, prlg_len, 0xc2); } /* FIXME: WTXM implementation */ static int tcl_prlg_len(struct tcl_handle *th) { int prlg_len = 1; if (th->flags & TCL_HANDLE_F_CID_USED) prlg_len++; if (th->flags & TCL_HANDLE_F_NAD_USED) prlg_len++; return prlg_len; } #define max_net_tx_framesize(x) (x->fsc - tcl_prlg_len(x)) static int tcl_connect(struct rfid_protocol_handle *h) { int ret; if (h->priv.tcl.state != TCL_STATE_DESELECTED && h->priv.tcl.state != TCL_STATE_INITIAL) return -1; switch (h->l2h->l2->id) { case RFID_LAYER2_ISO14443A: /* Start Type A T=CL Activation Sequence */ ret = tcl_request_ats(h); if (ret < 0) return ret; /* Only do PPS if any non-default divisors supported */ if (h->priv.tcl.ta & 0x77) { ret = tcl_do_pps(h); if (ret < 0) return ret; } break; case RFID_LAYER2_ISO14443B: /* initialized T=CL state from Type B Activation Data */ h->priv.tcl.cid = h->l2h->priv.iso14443b.cid; h->priv.tcl.fsc = h->l2h->priv.iso14443b.fsc; h->priv.tcl.fsd = h->l2h->priv.iso14443b.fsd; h->priv.tcl.fwt = h->l2h->priv.iso14443b.fwt; /* what about ta? sfgt? */ if (h->l2h->priv.iso14443b.flags & ISO14443B_CID_SUPPORTED) h->priv.tcl.flags |= TCL_HANDLE_F_CID_SUPPORTED; if (h->l2h->priv.iso14443b.flags & ISO14443B_NAD_SUPPORTED) h->priv.tcl.flags |= TCL_HANDLE_F_NAD_SUPPORTED; switch (h->l2h->priv.iso14443b.state) { case ISO14443B_STATE_SELECTED: h->priv.tcl.state = TCL_STATE_ATS_RCVD; break; case ISO14443B_STATE_ATTRIB_SENT: h->priv.tcl.state = TCL_STATE_RATS_SENT; break; } /* PUPI will be presented as ATS/historical bytes */ memcpy(h->priv.tcl.ats, h->l2h->uid, 4); h->priv.tcl.ats_len = 4; h->priv.tcl.historical_bytes = h->priv.tcl.ats; break; default: DEBUGP("unsupported l2: %u\n", h->l2h->l2->id); return -1; break; } return 0; } static int tcl_deselect(struct rfid_protocol_handle *h) { /* ISO 14443-4:2000(E) Section 8 */ int ret; unsigned char frame[3]; /* 3 bytes prologue, no information */ unsigned char rx[3]; unsigned int rx_len = sizeof(rx); unsigned int prlg_len; struct tcl_handle *th = &h->priv.tcl; if (th->state != TCL_STATE_ESTABLISHED) { /* FIXME: not sure whether deselect is possible here, * probably better send a HLTA? */ } /* build DESELECT S-block */ ret = tcl_build_prologue_s(th, frame, &prlg_len); if (ret < 0) return ret; ret = h->l2h->l2->fn.transcieve(h->l2h, RFID_14443A_FRAME_REGULAR, frame, prlg_len, rx, &rx_len, deactivation_fwt(h), TCL_TRANSP_F_TX_CRC); if (ret < 0) { /* FIXME: retransmit, HLT(A|B) */ return ret; } th->state = TCL_STATE_DESELECTED; return 0; } #define is_s_block(x) ((x & 0xc0) == 0xc0) #define is_r_block(x) ((x & 0xc0) == 0x80) #define is_i_block(x) ((x & 0xc0) == 0x00) static int tcl_transcieve(struct rfid_protocol_handle *h, const unsigned char *tx_data, unsigned int tx_len, unsigned char *rx_data, unsigned int *rx_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 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; if (tx_len > max_net_tx_framesize(th)) { /* slow path: we need to use chaining */ return -1; } 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; do_tx: ret = h->l2h->l2->fn.transcieve(h->l2h, l2_to_frame(h->l2h->l2->id), _tx, _tx_len, rx_buf, &_rx_len, _timeout, 0); DEBUGP("l2 transcieve finished\n"); if (ret < 0) goto out_rxb; if ((*rx_buf & 0x01) != h->priv.tcl.toggle) { DEBUGP("response with wrong toggle bit\n"); goto out_rxb; } if (is_r_block(*rx_buf)) { unsigned int txed = _tx - tx_buf; 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)) { 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) { DEBUGP("S-Block with CID but short len\n"); ret = -1; goto out_rxb; } 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); } else inf = *(rx_buf+1); if ((*rx_buf & 0x30) != 0x30) { DEBUGP("S-Block but not WTX?\n"); ret = -1; goto out_rxb; } 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; } /* 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; /* start over with next transcieve */ goto do_tx; /* FIXME: do transcieve locally since we use totally different buffer */ } else if (is_i_block(*rx_buf)) { unsigned char *inf = rx_buf+1; unsigned int net_payload_len; /* we're actually receiving payload data */ DEBUGP("I-Block\n"); 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; } inf++; } if (*rx_buf & TCL_PCB_NAD_FOLLOWING) { inf++; } net_payload_len = _rx_len - (inf - rx_buf); 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; if (*rx_buf & 0x10) { /* we're not the last frame in the chain, continue rx */ DEBUGP("we're 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; goto do_tx; } } out_rxb: free(rx_buf); out_txb: free(tx_buf); out: return ret; } #if 0 int tcl_send(struct tcl_handle *th) { return -1; } int tcl_recv() { return -1; } #endif static struct rfid_protocol_handle * tcl_init(struct rfid_layer2_handle *l2h) { struct rfid_protocol_handle *th; unsigned int mru = l2h->rh->ah->mru; th = malloc(sizeof(struct rfid_protocol_handle) + mru); if (!th) return NULL; /* FIXME: mru should be attribute of layer2 (in case it adds/removes * some overhead */ memset(th, 0, sizeof(struct rfid_protocol_handle) + mru); /* maximum received ats length equals mru of asic/reader */ th->priv.tcl.state = TCL_STATE_INITIAL; th->priv.tcl.ats_len = mru; th->priv.tcl.toggle = 1; th->priv.tcl.fsd = iso14443_fsd_approx(mru); return th; } static int tcl_fini(struct rfid_protocol_handle *ph) { free(ph); return 0; } struct rfid_protocol rfid_protocol_tcl = { .id = RFID_PROTOCOL_TCL, .name = "ISO 14443-4 / T=CL", .fn = { .init = &tcl_init, .open = &tcl_connect, .transcieve = &tcl_transcieve, .close = &tcl_deselect, .fini = &tcl_fini, }, };