| 1 | /* $NetBSD: dtv_demux.c,v 1.6 2014/08/09 13:34:10 jmcneill Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 2011 Jared D. McNeill <jmcneill@invisible.ca> |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * 3. All advertising materials mentioning features or use of this software |
| 16 | * must display the following acknowledgement: |
| 17 | * This product includes software developed by Jared D. McNeill. |
| 18 | * 4. Neither the name of The NetBSD Foundation nor the names of its |
| 19 | * contributors may be used to endorse or promote products derived |
| 20 | * from this software without specific prior written permission. |
| 21 | * |
| 22 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 23 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 24 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 25 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 26 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 27 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 28 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 29 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 30 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 31 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 32 | * POSSIBILITY OF SUCH DAMAGE. |
| 33 | */ |
| 34 | |
| 35 | /* |
| 36 | * This file contains support for the /dev/dvb/adapter<n>/demux0 device. |
| 37 | * |
| 38 | * The demux device is implemented as a cloning device. Each instance can |
| 39 | * be in one of three modes: unconfigured (NONE), section filter (SECTION), |
| 40 | * or PID filter (PES). |
| 41 | * |
| 42 | * An instance in section filter mode extracts PSI sections based on a |
| 43 | * filter configured by the DMX_SET_FILTER ioctl. When an entire section is |
| 44 | * received, it is made available to userspace via read method. Data is fed |
| 45 | * into the section filter using the dtv_demux_write function. |
| 46 | * |
| 47 | * An instance in PID filter mode extracts TS packets that match the |
| 48 | * specified PID filter configured by the DMX_SET_PES_FILTER, DMX_ADD_PID, |
| 49 | * and DMX_REMOVE_PID ioctls. As this driver only implements the |
| 50 | * DMX_OUT_TS_TAP output, these TS packets are made available to userspace |
| 51 | * by calling read on the /dev/dvb/adapter<n>/dvr0 device. |
| 52 | */ |
| 53 | |
| 54 | #include <sys/cdefs.h> |
| 55 | __KERNEL_RCSID(0, "$NetBSD: dtv_demux.c,v 1.6 2014/08/09 13:34:10 jmcneill Exp $" ); |
| 56 | |
| 57 | #include <sys/param.h> |
| 58 | #include <sys/types.h> |
| 59 | #include <sys/conf.h> |
| 60 | #include <sys/kmem.h> |
| 61 | #include <sys/device.h> |
| 62 | #include <sys/select.h> |
| 63 | #include <sys/filedesc.h> |
| 64 | #include <sys/file.h> |
| 65 | #include <sys/poll.h> |
| 66 | #include <sys/vnode.h> |
| 67 | #include <sys/queue.h> |
| 68 | |
| 69 | #include <dev/dtv/dtvvar.h> |
| 70 | |
| 71 | static int dtv_demux_read(struct file *, off_t *, struct uio *, |
| 72 | kauth_cred_t, int); |
| 73 | static int dtv_demux_ioctl(struct file *, u_long, void *); |
| 74 | static int dtv_demux_poll(struct file *, int); |
| 75 | static int dtv_demux_close(struct file *); |
| 76 | |
| 77 | static const struct fileops dtv_demux_fileops = { |
| 78 | .fo_read = dtv_demux_read, |
| 79 | .fo_write = fbadop_write, |
| 80 | .fo_ioctl = dtv_demux_ioctl, |
| 81 | .fo_fcntl = fnullop_fcntl, |
| 82 | .fo_poll = dtv_demux_poll, |
| 83 | .fo_stat = fbadop_stat, |
| 84 | .fo_close = dtv_demux_close, |
| 85 | .fo_kqfilter = fnullop_kqfilter, |
| 86 | .fo_restart = fnullop_restart, |
| 87 | }; |
| 88 | |
| 89 | static uint32_t crc_table[256] = { |
| 90 | 0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, |
| 91 | 0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005, |
| 92 | 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61, |
| 93 | 0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, |
| 94 | 0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9, |
| 95 | 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75, |
| 96 | 0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, |
| 97 | 0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd, |
| 98 | 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039, |
| 99 | 0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, |
| 100 | 0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81, |
| 101 | 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d, |
| 102 | 0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, |
| 103 | 0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95, |
| 104 | 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1, |
| 105 | 0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, |
| 106 | 0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae, |
| 107 | 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072, |
| 108 | 0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, |
| 109 | 0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca, |
| 110 | 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde, |
| 111 | 0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, |
| 112 | 0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066, |
| 113 | 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba, |
| 114 | 0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, |
| 115 | 0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692, |
| 116 | 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6, |
| 117 | 0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, |
| 118 | 0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e, |
| 119 | 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2, |
| 120 | 0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, |
| 121 | 0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a, |
| 122 | 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637, |
| 123 | 0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, |
| 124 | 0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f, |
| 125 | 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53, |
| 126 | 0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, |
| 127 | 0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b, |
| 128 | 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff, |
| 129 | 0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, |
| 130 | 0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7, |
| 131 | 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b, |
| 132 | 0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, |
| 133 | 0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3, |
| 134 | 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7, |
| 135 | 0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, |
| 136 | 0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f, |
| 137 | 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3, |
| 138 | 0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, |
| 139 | 0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c, |
| 140 | 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8, |
| 141 | 0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, |
| 142 | 0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30, |
| 143 | 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec, |
| 144 | 0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, |
| 145 | 0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654, |
| 146 | 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0, |
| 147 | 0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, |
| 148 | 0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18, |
| 149 | 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4, |
| 150 | 0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, |
| 151 | 0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c, |
| 152 | 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668, |
| 153 | 0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4 |
| 154 | }; |
| 155 | |
| 156 | /* ISO/IEC 13818-1 Annex A "CRC Decoder Model" */ |
| 157 | static uint32_t |
| 158 | dtv_demux_crc32(uint8_t *buf, int len) |
| 159 | { |
| 160 | const uint32_t *crc_tab = crc_table; |
| 161 | uint32_t CRC = 0xffffffff; |
| 162 | int i; |
| 163 | |
| 164 | for (i = 0; i < len; i++) |
| 165 | CRC = (CRC << 8) ^ crc_tab[((CRC >> 24) ^ *buf++) & 0xff]; |
| 166 | |
| 167 | return CRC; |
| 168 | } |
| 169 | |
| 170 | /* |
| 171 | * Start running the demux. |
| 172 | */ |
| 173 | static int |
| 174 | dtv_demux_start(struct dtv_demux *demux) |
| 175 | { |
| 176 | struct dtv_softc *sc = demux->dd_sc; |
| 177 | int error = 0; |
| 178 | bool dostart = false; |
| 179 | |
| 180 | /* |
| 181 | * If the demux is not running, mark it as running and update the |
| 182 | * global demux run counter. |
| 183 | */ |
| 184 | mutex_enter(&sc->sc_lock); |
| 185 | KASSERT(sc->sc_demux_runcnt >= 0); |
| 186 | if (demux->dd_running == false) { |
| 187 | sc->sc_demux_runcnt++; |
| 188 | demux->dd_running = true; |
| 189 | /* If this is the first demux running, trigger device start */ |
| 190 | dostart = sc->sc_demux_runcnt == 1; |
| 191 | } |
| 192 | mutex_exit(&sc->sc_lock); |
| 193 | |
| 194 | if (dostart) { |
| 195 | /* Setup receive buffers and trigger device start */ |
| 196 | error = dtv_buffer_setup(sc); |
| 197 | if (error == 0) |
| 198 | error = dtv_device_start_transfer(sc); |
| 199 | } |
| 200 | |
| 201 | /* |
| 202 | * If something went wrong, restore the run counter and mark this |
| 203 | * demux instance as halted. |
| 204 | */ |
| 205 | if (error) { |
| 206 | mutex_enter(&sc->sc_lock); |
| 207 | sc->sc_demux_runcnt--; |
| 208 | demux->dd_running = false; |
| 209 | mutex_exit(&sc->sc_lock); |
| 210 | } |
| 211 | |
| 212 | return error; |
| 213 | } |
| 214 | |
| 215 | /* |
| 216 | * Stop running the demux. |
| 217 | */ |
| 218 | static int |
| 219 | dtv_demux_stop(struct dtv_demux *demux) |
| 220 | { |
| 221 | struct dtv_softc *sc = demux->dd_sc; |
| 222 | int error = 0; |
| 223 | bool dostop = false; |
| 224 | |
| 225 | /* |
| 226 | * If the demux is running, mark it as halted and update the |
| 227 | * global demux run counter. |
| 228 | */ |
| 229 | mutex_enter(&sc->sc_lock); |
| 230 | if (demux->dd_running == true) { |
| 231 | KASSERT(sc->sc_demux_runcnt > 0); |
| 232 | demux->dd_running = false; |
| 233 | sc->sc_demux_runcnt--; |
| 234 | /* If this was the last demux running, trigger device stop */ |
| 235 | dostop = sc->sc_demux_runcnt == 0; |
| 236 | } |
| 237 | mutex_exit(&sc->sc_lock); |
| 238 | |
| 239 | if (dostop) { |
| 240 | /* Trigger device stop */ |
| 241 | error = dtv_device_stop_transfer(sc); |
| 242 | } |
| 243 | |
| 244 | /* |
| 245 | * If something went wrong, restore the run counter and mark this |
| 246 | * demux instance as running. |
| 247 | */ |
| 248 | if (error) { |
| 249 | mutex_enter(&sc->sc_lock); |
| 250 | sc->sc_demux_runcnt++; |
| 251 | demux->dd_running = true; |
| 252 | mutex_exit(&sc->sc_lock); |
| 253 | } |
| 254 | |
| 255 | return error; |
| 256 | } |
| 257 | |
| 258 | /* |
| 259 | * Put the demux into PID filter mode and update the PID filter table. |
| 260 | */ |
| 261 | static int |
| 262 | dtv_demux_set_pidfilter(struct dtv_demux *demux, uint16_t pid, bool onoff) |
| 263 | { |
| 264 | struct dtv_softc *sc = demux->dd_sc; |
| 265 | |
| 266 | /* |
| 267 | * TS PID is 13 bits; demux device uses special PID 0x2000 to mean |
| 268 | * "all PIDs". Verify that the requested PID is in range. |
| 269 | */ |
| 270 | if (pid > 0x2000) |
| 271 | return EINVAL; |
| 272 | |
| 273 | /* Set demux mode */ |
| 274 | demux->dd_mode = DTV_DEMUX_MODE_PES; |
| 275 | /* |
| 276 | * If requesting "all PIDs", set the on/off flag for all PIDs in |
| 277 | * the PID map, otherwise set the on/off flag for the requested |
| 278 | * PID. |
| 279 | */ |
| 280 | if (pid == 0x2000) { |
| 281 | memset(sc->sc_ts.ts_pidfilter, onoff, |
| 282 | sizeof(sc->sc_ts.ts_pidfilter)); |
| 283 | } else { |
| 284 | sc->sc_ts.ts_pidfilter[pid] = onoff; |
| 285 | } |
| 286 | |
| 287 | return 0; |
| 288 | } |
| 289 | |
| 290 | /* |
| 291 | * Open a new instance of the demux cloning device. |
| 292 | */ |
| 293 | int |
| 294 | dtv_demux_open(struct dtv_softc *sc, int flags, int mode, lwp_t *l) |
| 295 | { |
| 296 | struct file *fp; |
| 297 | struct dtv_demux *demux; |
| 298 | int error, fd; |
| 299 | |
| 300 | /* Allocate private storage */ |
| 301 | demux = kmem_zalloc(sizeof(*demux), KM_SLEEP); |
| 302 | if (demux == NULL) |
| 303 | return ENOMEM; |
| 304 | demux->dd_sc = sc; |
| 305 | /* Default operation mode is unconfigured */ |
| 306 | demux->dd_mode = DTV_DEMUX_MODE_NONE; |
| 307 | selinit(&demux->dd_sel); |
| 308 | mutex_init(&demux->dd_lock, MUTEX_DEFAULT, IPL_SCHED); |
| 309 | cv_init(&demux->dd_section_cv, "dtvsec" ); |
| 310 | |
| 311 | error = fd_allocfile(&fp, &fd); |
| 312 | if (error) { |
| 313 | kmem_free(demux, sizeof(*demux)); |
| 314 | return error; |
| 315 | } |
| 316 | |
| 317 | /* Add the demux to the list of demux instances */ |
| 318 | mutex_enter(&sc->sc_demux_lock); |
| 319 | TAILQ_INSERT_TAIL(&sc->sc_demux_list, demux, dd_entries); |
| 320 | mutex_exit(&sc->sc_demux_lock); |
| 321 | |
| 322 | return fd_clone(fp, fd, flags, &dtv_demux_fileops, demux); |
| 323 | } |
| 324 | |
| 325 | /* |
| 326 | * Close the instance of the demux cloning device. |
| 327 | */ |
| 328 | int |
| 329 | dtv_demux_close(struct file *fp) |
| 330 | { |
| 331 | struct dtv_demux *demux = fp->f_data; |
| 332 | struct dtv_softc *sc; |
| 333 | int error; |
| 334 | |
| 335 | if (demux == NULL) |
| 336 | return ENXIO; |
| 337 | |
| 338 | fp->f_data = NULL; |
| 339 | |
| 340 | sc = demux->dd_sc; |
| 341 | |
| 342 | /* If the demux is still running, stop it */ |
| 343 | if (demux->dd_running) { |
| 344 | error = dtv_demux_stop(demux); |
| 345 | if (error) |
| 346 | return error; |
| 347 | } |
| 348 | |
| 349 | /* Remove the demux from the list of demux instances */ |
| 350 | mutex_enter(&sc->sc_demux_lock); |
| 351 | TAILQ_REMOVE(&sc->sc_demux_list, demux, dd_entries); |
| 352 | mutex_exit(&sc->sc_demux_lock); |
| 353 | |
| 354 | mutex_destroy(&demux->dd_lock); |
| 355 | cv_destroy(&demux->dd_section_cv); |
| 356 | kmem_free(demux, sizeof(*demux)); |
| 357 | |
| 358 | /* Update the global device open count */ |
| 359 | dtv_common_close(sc); |
| 360 | |
| 361 | return 0; |
| 362 | } |
| 363 | |
| 364 | /* |
| 365 | * Handle demux ioctl requests |
| 366 | */ |
| 367 | static int |
| 368 | dtv_demux_ioctl(struct file *fp, u_long cmd, void *data) |
| 369 | { |
| 370 | struct dtv_demux *demux = fp->f_data; |
| 371 | struct dmx_pes_filter_params *pesfilt; |
| 372 | struct dmx_sct_filter_params *sctfilt; |
| 373 | uint16_t pid; |
| 374 | int error; |
| 375 | |
| 376 | if (demux == NULL) |
| 377 | return ENXIO; |
| 378 | |
| 379 | switch (cmd) { |
| 380 | case DMX_START: |
| 381 | return dtv_demux_start(demux); |
| 382 | case DMX_STOP: |
| 383 | return dtv_demux_stop(demux); |
| 384 | case DMX_SET_BUFFER_SIZE: |
| 385 | /* |
| 386 | * The demux driver doesn't support configurable buffer sizes, |
| 387 | * but software relies on this command succeeding. |
| 388 | */ |
| 389 | return 0; |
| 390 | case DMX_SET_FILTER: |
| 391 | sctfilt = data; |
| 392 | |
| 393 | /* Verify that the requested PID is in range. */ |
| 394 | if (sctfilt->pid >= 0x2000) |
| 395 | return EINVAL; |
| 396 | |
| 397 | /* |
| 398 | * Update section filter parameters, reset read/write ptrs, |
| 399 | * clear section count and overflow flag, and set the |
| 400 | * demux instance mode to section filter. |
| 401 | */ |
| 402 | demux->dd_secfilt.params = *sctfilt; |
| 403 | demux->dd_secfilt.rp = demux->dd_secfilt.wp = 0; |
| 404 | demux->dd_secfilt.nsections = 0; |
| 405 | demux->dd_secfilt.overflow = false; |
| 406 | demux->dd_mode = DTV_DEMUX_MODE_SECTION; |
| 407 | |
| 408 | /* |
| 409 | * If the DMX_IMMEDIATE_START flag is present in the request, |
| 410 | * start running the demux immediately (no need for a |
| 411 | * subsequent DMX_START ioctl). |
| 412 | */ |
| 413 | if (sctfilt->flags & DMX_IMMEDIATE_START) { |
| 414 | error = dtv_demux_start(demux); |
| 415 | if (error) |
| 416 | return error; |
| 417 | } |
| 418 | |
| 419 | return 0; |
| 420 | case DMX_SET_PES_FILTER: |
| 421 | pesfilt = data; |
| 422 | |
| 423 | /* The driver only supports input from the frontend */ |
| 424 | if (pesfilt->input != DMX_IN_FRONTEND) |
| 425 | return EINVAL; |
| 426 | /* |
| 427 | * The driver only supports output to the TS TAP in PID |
| 428 | * filter mode. |
| 429 | */ |
| 430 | if (pesfilt->output != DMX_OUT_TS_TAP) |
| 431 | return EINVAL; |
| 432 | |
| 433 | /* Update PID filter table */ |
| 434 | error = dtv_demux_set_pidfilter(demux, pesfilt->pid, true); |
| 435 | if (error) |
| 436 | return error; |
| 437 | |
| 438 | /* |
| 439 | * If the DMX_IMMEDIATE_START flag is present in the request, |
| 440 | * start running the demux immediately (no need for a |
| 441 | * subsequent DMX_START ioctl). |
| 442 | */ |
| 443 | if (pesfilt->flags & DMX_IMMEDIATE_START) { |
| 444 | error = dtv_demux_start(demux); |
| 445 | if (error) |
| 446 | return error; |
| 447 | } |
| 448 | return 0; |
| 449 | case DMX_ADD_PID: |
| 450 | pid = *(uint16_t *)data; |
| 451 | return dtv_demux_set_pidfilter(demux, pid, true); |
| 452 | case DMX_REMOVE_PID: |
| 453 | pid = *(uint16_t *)data; |
| 454 | return dtv_demux_set_pidfilter(demux, pid, false); |
| 455 | default: |
| 456 | return EINVAL; |
| 457 | } |
| 458 | } |
| 459 | |
| 460 | /* |
| 461 | * Test for I/O readiness |
| 462 | */ |
| 463 | static int |
| 464 | dtv_demux_poll(struct file *fp, int events) |
| 465 | { |
| 466 | struct dtv_demux *demux = fp->f_data; |
| 467 | int revents = 0; |
| 468 | |
| 469 | if (demux == NULL) |
| 470 | return POLLERR; |
| 471 | |
| 472 | /* |
| 473 | * If the demux instance is in section filter mode, wait for an |
| 474 | * entire section to become ready. |
| 475 | */ |
| 476 | mutex_enter(&demux->dd_lock); |
| 477 | if (demux->dd_mode == DTV_DEMUX_MODE_SECTION && |
| 478 | demux->dd_secfilt.nsections > 0) { |
| 479 | revents |= POLLIN; |
| 480 | } else { |
| 481 | selrecord(curlwp, &demux->dd_sel); |
| 482 | } |
| 483 | mutex_exit(&demux->dd_lock); |
| 484 | |
| 485 | return revents; |
| 486 | } |
| 487 | |
| 488 | /* |
| 489 | * Read from the demux instance |
| 490 | */ |
| 491 | static int |
| 492 | dtv_demux_read(struct file *fp, off_t *offp, struct uio *uio, |
| 493 | kauth_cred_t cred, int flags) |
| 494 | { |
| 495 | struct dtv_demux *demux = fp->f_data; |
| 496 | struct dtv_ts_section sec; |
| 497 | int error; |
| 498 | |
| 499 | if (demux == NULL) |
| 500 | return ENXIO; |
| 501 | |
| 502 | /* Only support read if the instance is in section filter mode */ |
| 503 | if (demux->dd_mode != DTV_DEMUX_MODE_SECTION) |
| 504 | return EIO; |
| 505 | |
| 506 | /* Wait for a complete PSI section */ |
| 507 | mutex_enter(&demux->dd_lock); |
| 508 | while (demux->dd_secfilt.nsections == 0) { |
| 509 | if (flags & IO_NDELAY) { |
| 510 | mutex_exit(&demux->dd_lock); |
| 511 | /* No data available */ |
| 512 | return EWOULDBLOCK; |
| 513 | } |
| 514 | error = cv_wait_sig(&demux->dd_section_cv, &demux->dd_lock); |
| 515 | if (error) { |
| 516 | mutex_exit(&demux->dd_lock); |
| 517 | return error; |
| 518 | } |
| 519 | } |
| 520 | /* Copy the completed PSI section */ |
| 521 | sec = demux->dd_secfilt.section[demux->dd_secfilt.rp]; |
| 522 | /* Update read pointer */ |
| 523 | demux->dd_secfilt.rp++; |
| 524 | if (demux->dd_secfilt.rp >= __arraycount(demux->dd_secfilt.section)) |
| 525 | demux->dd_secfilt.rp = 0; |
| 526 | /* Update section count */ |
| 527 | demux->dd_secfilt.nsections--; |
| 528 | mutex_exit(&demux->dd_lock); |
| 529 | |
| 530 | /* |
| 531 | * If the filter parameters specify the DMX_ONESHOT flag, stop |
| 532 | * the demux after one PSI section is received. |
| 533 | */ |
| 534 | if (demux->dd_secfilt.params.flags & DMX_ONESHOT) |
| 535 | dtv_demux_stop(demux); |
| 536 | |
| 537 | /* |
| 538 | * Copy the PSI section to userspace. If the receiving buffer is |
| 539 | * too small, the rest of the payload will be discarded. Although |
| 540 | * this behaviour differs from the Linux implementation, in practice |
| 541 | * it should not be an issue as PSI sections have a max size of 4KB |
| 542 | * (and callers will generally provide a big enough buffer). |
| 543 | */ |
| 544 | return uiomove(sec.sec_buf, sec.sec_length, uio); |
| 545 | } |
| 546 | |
| 547 | /* |
| 548 | * Verify the CRC of a PSI section. |
| 549 | */ |
| 550 | static bool |
| 551 | dtv_demux_check_crc(struct dtv_demux *demux, struct dtv_ts_section *sec) |
| 552 | { |
| 553 | uint32_t crc, sec_crc; |
| 554 | |
| 555 | /* |
| 556 | * If section_syntax_indicator is not set, the PSI section does |
| 557 | * not include a CRC field. |
| 558 | */ |
| 559 | if ((sec->sec_buf[1] & 0x80) == 0) |
| 560 | return false; |
| 561 | |
| 562 | sec_crc = be32dec(&sec->sec_buf[sec->sec_length - 4]); |
| 563 | crc = dtv_demux_crc32(&sec->sec_buf[0], sec->sec_length - 4); |
| 564 | |
| 565 | return crc == sec_crc; |
| 566 | } |
| 567 | |
| 568 | /* |
| 569 | * Process a single TS packet and extract PSI sections based on the |
| 570 | * instance's section filter. |
| 571 | */ |
| 572 | static int |
| 573 | dtv_demux_process(struct dtv_demux *demux, const uint8_t *tspkt, |
| 574 | size_t tspktlen) |
| 575 | { |
| 576 | struct dtv_ts_section *sec; |
| 577 | dmx_filter_t *dmxfilt = &demux->dd_secfilt.params.filter; |
| 578 | const uint8_t *p; |
| 579 | uint16_t section_length; |
| 580 | int brem, avail; |
| 581 | |
| 582 | KASSERT(tspktlen == TS_PKTLEN); |
| 583 | |
| 584 | /* If the demux instance is not running, ignore the packet */ |
| 585 | if (demux->dd_running == false) |
| 586 | return 0; |
| 587 | |
| 588 | /* |
| 589 | * If the demux instance is not in section filter mode, ignore |
| 590 | * the packet |
| 591 | */ |
| 592 | if (demux->dd_mode != DTV_DEMUX_MODE_SECTION) |
| 593 | return 0; |
| 594 | /* |
| 595 | * If the packet's TS PID does not match the section filter PID, |
| 596 | * ignore the packet |
| 597 | */ |
| 598 | if (TS_PID(tspkt) != demux->dd_secfilt.params.pid) |
| 599 | return 0; |
| 600 | /* |
| 601 | * If the TS packet does not contain a payload, ignore the packet |
| 602 | */ |
| 603 | if (TS_HAS_PAYLOAD(tspkt) == 0) |
| 604 | return 0; |
| 605 | |
| 606 | mutex_enter(&demux->dd_lock); |
| 607 | |
| 608 | /* If the section buffer is full, set the overflow flag and return */ |
| 609 | if (demux->dd_secfilt.nsections == |
| 610 | __arraycount(demux->dd_secfilt.section)) { |
| 611 | demux->dd_secfilt.overflow = true; |
| 612 | goto done; |
| 613 | } |
| 614 | sec = &demux->dd_secfilt.section[demux->dd_secfilt.wp]; |
| 615 | /* If we have no bytes in our buffer, wait for payload unit start */ |
| 616 | if (sec->sec_bytesused == 0 && TS_HAS_PUSI(tspkt) == 0) |
| 617 | goto done; |
| 618 | |
| 619 | /* find payload start */ |
| 620 | p = tspkt + 4; |
| 621 | if (TS_HAS_AF(tspkt)) { |
| 622 | if (*p > 182) /* AF length with payload is between 0-182 */ |
| 623 | goto done; |
| 624 | p += (1 + *p); |
| 625 | } |
| 626 | if (TS_HAS_PUSI(tspkt)) { |
| 627 | p += (1 + *p); |
| 628 | } |
| 629 | |
| 630 | brem = tspktlen - (p - tspkt); |
| 631 | |
| 632 | if (TS_HAS_PUSI(tspkt)) { |
| 633 | if (brem < 16) |
| 634 | goto done; |
| 635 | |
| 636 | section_length = ((p[1] & 0xf) << 8) | p[2]; |
| 637 | |
| 638 | /* table_id filter */ |
| 639 | if (dmxfilt->mask[0]) { |
| 640 | if ((p[0] & dmxfilt->mask[0]) != dmxfilt->filter[0]) |
| 641 | goto done; |
| 642 | } |
| 643 | /* table_id_ext filter */ |
| 644 | if (dmxfilt->mask[1] && dmxfilt->mask[2]) { |
| 645 | /* |
| 646 | * table_id_ext is only valid if |
| 647 | * section_syntax_indicator is set |
| 648 | */ |
| 649 | if (section_length < 2 || (p[1] & 0x80) == 0) |
| 650 | goto done; |
| 651 | if ((p[3] & dmxfilt->mask[1]) != dmxfilt->filter[1]) |
| 652 | goto done; |
| 653 | if ((p[4] & dmxfilt->mask[2]) != dmxfilt->filter[2]) |
| 654 | goto done; |
| 655 | } |
| 656 | |
| 657 | sec->sec_length = section_length + 3; |
| 658 | |
| 659 | /* maximum section length is 4KB */ |
| 660 | if (sec->sec_length > sizeof(sec->sec_buf)) { |
| 661 | sec->sec_bytesused = sec->sec_length = 0; |
| 662 | goto done; |
| 663 | } |
| 664 | |
| 665 | } |
| 666 | |
| 667 | /* If we have bytes pending and we see payload unit start, flush buf */ |
| 668 | if (sec->sec_bytesused > 0 && TS_HAS_PUSI(tspkt)) |
| 669 | sec->sec_bytesused = sec->sec_length = 0; |
| 670 | |
| 671 | /* Copy data into section buffer */ |
| 672 | avail = min(sec->sec_length - sec->sec_bytesused, brem); |
| 673 | if (avail < 0) |
| 674 | goto done; |
| 675 | memcpy(&sec->sec_buf[sec->sec_bytesused], p, avail); |
| 676 | sec->sec_bytesused += avail; |
| 677 | |
| 678 | /* |
| 679 | * If a complete section has been received, update section count |
| 680 | * and notify readers. |
| 681 | */ |
| 682 | if (sec->sec_bytesused == sec->sec_length) { |
| 683 | /* |
| 684 | * If the DMX_CHECK_CRC flag was present in the DMX_SET_FILTER |
| 685 | * parameters, verify the PSI section checksum. If the |
| 686 | * checksum is invalid, discard the entire corrupt section. |
| 687 | */ |
| 688 | if ((demux->dd_secfilt.params.flags & DMX_CHECK_CRC) && |
| 689 | dtv_demux_check_crc(demux, sec) == false) { |
| 690 | /* discard section */ |
| 691 | sec->sec_bytesused = sec->sec_length = 0; |
| 692 | goto done; |
| 693 | } |
| 694 | |
| 695 | demux->dd_secfilt.wp++; |
| 696 | if (demux->dd_secfilt.wp >= |
| 697 | __arraycount(demux->dd_secfilt.section)) |
| 698 | demux->dd_secfilt.wp = 0; |
| 699 | demux->dd_secfilt.nsections++; |
| 700 | cv_broadcast(&demux->dd_section_cv); |
| 701 | selnotify(&demux->dd_sel, 0, 0); |
| 702 | } |
| 703 | |
| 704 | done: |
| 705 | mutex_exit(&demux->dd_lock); |
| 706 | return 0; |
| 707 | } |
| 708 | |
| 709 | /* |
| 710 | * Submit TS data to all demux instances |
| 711 | */ |
| 712 | void |
| 713 | dtv_demux_write(struct dtv_softc *sc, const uint8_t *tspkt, size_t tspktlen) |
| 714 | { |
| 715 | struct dtv_demux *demux; |
| 716 | |
| 717 | mutex_enter(&sc->sc_demux_lock); |
| 718 | TAILQ_FOREACH(demux, &sc->sc_demux_list, dd_entries) { |
| 719 | dtv_demux_process(demux, tspkt, tspktlen); |
| 720 | } |
| 721 | mutex_exit(&sc->sc_demux_lock); |
| 722 | } |
| 723 | |