1 /* 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1991 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: @(#)cons.c 7.2 (Berkeley) 5/9/91 39 * $FreeBSD: src/sys/kern/tty_cons.c,v 1.81.2.4 2001/12/17 18:44:41 guido Exp $ 40 */ 41 42 #include "opt_ddb.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/conf.h> 47 #include <sys/cons.h> 48 #include <sys/kernel.h> 49 #include <sys/proc.h> 50 #include <sys/priv.h> 51 #include <sys/reboot.h> 52 #include <sys/sysctl.h> 53 #include <sys/tty.h> 54 #include <sys/uio.h> 55 #include <sys/msgport.h> 56 #include <sys/msgport2.h> 57 #include <sys/device.h> 58 59 #include <ddb/ddb.h> 60 61 #include <machine/cpu.h> 62 63 static d_open_t cnopen; 64 static d_close_t cnclose; 65 static d_read_t cnread; 66 static d_write_t cnwrite; 67 static d_ioctl_t cnioctl; 68 static d_kqfilter_t cnkqfilter; 69 70 static int cnintercept(struct dev_generic_args *ap); 71 72 #define CDEV_MAJOR 0 73 static struct dev_ops cn_ops = { 74 { "console", 0, D_TTY }, 75 .d_open = cnopen, 76 .d_close = cnclose, 77 .d_read = cnread, 78 .d_write = cnwrite, 79 .d_ioctl = cnioctl, 80 .d_kqfilter = cnkqfilter, 81 }; 82 83 static struct dev_ops cn_iops = { 84 { "intercept", 0, D_TTY }, 85 .d_default = cnintercept 86 }; 87 88 static struct dev_ops *cn_fwd_ops; 89 static cdev_t cn_dev; 90 91 //XXX: get this shit out! (alexh) 92 #if 0 93 SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD, 94 &cn_udev, sizeof cn_udev, "T,udev_t", ""); 95 #endif 96 97 static int cn_mute; 98 99 int cons_unavail = 0; /* XXX: 100 * physical console not available for 101 * input (i.e., it is in graphics mode) 102 */ 103 int sysbeep_enable = 1; 104 105 static u_char cn_is_open; /* nonzero if logical console is open */ 106 static int openmode, openflag; /* how /dev/console was openned */ 107 static cdev_t cn_devfsdev; /* represents the device private info */ 108 static u_char cn_phys_is_open; /* nonzero if physical device is open */ 109 static u_char console_pausing; /* pause after each line during probe */ 110 static char *console_pausestr= 111 "<pause; press any key to proceed to next line or '.' to end pause mode>"; 112 113 struct consdev *cn_tab; /* physical console device info */ 114 struct consdev *gdb_tab; /* physical gdb debugger device info */ 115 116 SYSCTL_INT(_kern, OID_AUTO, sysbeep_enable, CTLFLAG_RW, &sysbeep_enable, 0, ""); 117 118 CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL); 119 SET_DECLARE(cons_set, struct consdev); 120 121 void 122 cninit(void) 123 { 124 struct consdev *best_cp, *cp, **list; 125 126 /* 127 * Workaround for token acquisition and releases during the 128 * console init. For some reason if lwkt_gettoken()'s mpcount 129 * optimization is turned off the console init blows up. It 130 * might be trying to kprintf() something in the middle of 131 * its init. 132 */ 133 lwkt_gettoken(&tty_token); 134 135 /* 136 * Check if we should mute the console (for security reasons perhaps) 137 * It can be changes dynamically using sysctl kern.consmute 138 * once we are up and going. 139 * 140 */ 141 cn_mute = ((boothowto & (RB_MUTE 142 |RB_SINGLE 143 |RB_VERBOSE 144 |RB_ASKNAME 145 |RB_CONFIG)) == RB_MUTE); 146 147 /* 148 * Find the first console with the highest priority. 149 */ 150 best_cp = NULL; 151 SET_FOREACH(list, cons_set) { 152 cp = *list; 153 if (cp->cn_probe == NULL) 154 continue; 155 (*cp->cn_probe)(cp); 156 if (cp->cn_pri > CN_DEAD && cp->cn_probegood && 157 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri)) 158 best_cp = cp; 159 } 160 161 162 /* 163 * If no console, give up. 164 */ 165 if (best_cp == NULL) { 166 if (cn_tab != NULL && cn_tab->cn_term != NULL) 167 (*cn_tab->cn_term)(cn_tab); 168 goto done; 169 } 170 171 /* 172 * Initialize console, then attach to it. This ordering allows 173 * debugging using the previous console, if any. 174 */ 175 (*best_cp->cn_init)(best_cp); 176 if (cn_tab != NULL && cn_tab != best_cp) { 177 /* Turn off the previous console. */ 178 if (cn_tab->cn_term != NULL) 179 (*cn_tab->cn_term)(cn_tab); 180 } 181 if (boothowto & RB_PAUSE) 182 console_pausing = 1; 183 done: 184 cn_tab = best_cp; 185 186 /* 187 * We can safely release the token after the init is done. 188 * Also assert that the mpcount is still correct or otherwise 189 * the SMP/AP boot will blow up on us. 190 */ 191 lwkt_reltoken(&tty_token); 192 #ifdef SMP 193 KKASSERT(curthread->td_mpcount == 1); 194 #endif 195 } 196 197 198 /* 199 * Hook the open and close functions on the selected device. 200 */ 201 void 202 cninit_finish(void) 203 { 204 if ((cn_tab == NULL) || cn_mute) 205 return; 206 if (cn_tab->cn_dev == NULL) { 207 cn_tab->cn_init_fini(cn_tab); 208 if (cn_tab->cn_dev == NULL) { 209 kprintf("Unable to hook console! cn_tab %p\n", cn_tab); 210 return; 211 } 212 } 213 214 cn_fwd_ops = dev_ops_intercept(cn_tab->cn_dev, &cn_iops); 215 cn_dev = cn_tab->cn_dev; 216 console_pausing = 0; 217 } 218 219 static void 220 cnuninit(void) 221 { 222 if (cn_tab == NULL) 223 return; 224 if (cn_fwd_ops) 225 dev_ops_restore(cn_tab->cn_dev, cn_fwd_ops); 226 cn_fwd_ops = NULL; 227 cn_dev = NULL; 228 } 229 230 231 /* 232 * User has changed the state of the console muting. 233 * This may require us to open or close the device in question. 234 */ 235 static int 236 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS) 237 { 238 int error; 239 int ocn_mute; 240 241 ocn_mute = cn_mute; 242 error = sysctl_handle_int(oidp, &cn_mute, 0, req); 243 if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) { 244 if(ocn_mute && !cn_mute) { 245 /* 246 * going from muted to unmuted.. open the physical dev 247 * if the console has been openned 248 */ 249 cninit_finish(); 250 if (cn_is_open) { 251 /* XXX curproc is not what we want really */ 252 error = dev_dopen(cn_dev, openflag, 253 openmode, curproc->p_ucred); 254 } 255 /* if it failed, back it out */ 256 if ( error != 0) cnuninit(); 257 } else if (!ocn_mute && cn_mute) { 258 /* 259 * going from unmuted to muted.. close the physical dev 260 * if it's only open via /dev/console 261 */ 262 if (cn_is_open) { 263 error = dev_dclose(cn_dev, openflag, 264 openmode); 265 } 266 if (error == 0) 267 cnuninit(); 268 } 269 if (error != 0) { 270 /* 271 * back out the change if there was an error 272 */ 273 cn_mute = ocn_mute; 274 } 275 } 276 return (error); 277 } 278 279 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW, 280 0, sizeof cn_mute, sysctl_kern_consmute, "I", ""); 281 282 283 /* 284 * We intercept the OPEN and CLOSE calls on the original device, and 285 * forward the rest through. 286 */ 287 static int 288 cnintercept(struct dev_generic_args *ap) 289 { 290 int error; 291 292 if (ap->a_desc == &dev_open_desc) { 293 error = cnopen((struct dev_open_args *)ap); 294 } else if (ap->a_desc == &dev_close_desc) { 295 error = cnclose((struct dev_close_args *)ap); 296 } else if (cn_fwd_ops) { 297 error = dev_doperate_ops(cn_fwd_ops, ap); 298 } else { 299 error = ENXIO; 300 } 301 return (error); 302 } 303 304 /* 305 * cnopen() is called as an intercept function (dev will be that of the 306 * actual physical device representing our console), and also called from 307 * the muting code and from the /dev/console switch (dev will have the 308 * console's cdevsw). 309 */ 310 static int 311 cnopen(struct dev_open_args *ap) 312 { 313 cdev_t dev = ap->a_head.a_dev; 314 int flag = ap->a_oflags; 315 int mode = ap->a_devtype; 316 cdev_t cndev; 317 cdev_t physdev; 318 int retval = 0; 319 320 if (cn_tab == NULL || cn_fwd_ops == NULL) 321 return (0); 322 323 cndev = cn_tab->cn_dev; /* actual physical device */ 324 physdev = (dev == cn_devfsdev) ? cndev : dev; 325 326 /* 327 * If mute is active, then non console opens don't get here 328 * so we don't need to check for that. They bypass this and go 329 * straight to the device. 330 * 331 * It is important to note that due to our intercept and the fact 332 * that we might be called via the original (intercepted) device, 333 * the original device's ops may point to us, so to avoid an 334 * infinite recursion we have to forward through cn_fwd_ops. 335 * This is a severe hack that really needs to be fixed XXX. 336 * 337 * XXX at the moment we assume that the port forwarding function 338 * is synchronous for open. 339 */ 340 if (!cn_mute) { 341 ap->a_head.a_dev = physdev; 342 retval = dev_doperate_ops(cn_fwd_ops, &ap->a_head); 343 } 344 if (retval == 0) { 345 /* 346 * check if we openned it via /dev/console or 347 * via the physical entry (e.g. /dev/sio0). 348 */ 349 if (dev == cndev) { 350 cn_phys_is_open = 1; 351 } else if (physdev == cndev) { 352 openmode = mode; 353 openflag = flag; 354 cn_is_open = 1; 355 } 356 dev->si_tty = cndev->si_tty; 357 } 358 return (retval); 359 } 360 361 /* 362 * cnclose() is called as a port intercept function (dev will be that of the 363 * actual physical device representing our console), and also called from 364 * the muting code and from the /dev/console switch (dev will have the 365 * console's cdevsw). 366 */ 367 static int 368 cnclose(struct dev_close_args *ap) 369 { 370 struct tty *cn_tp; 371 cdev_t cndev; 372 cdev_t physdev; 373 cdev_t dev = ap->a_head.a_dev; 374 375 if (cn_tab == NULL || cn_fwd_ops == NULL) 376 return(0); 377 cndev = cn_tab->cn_dev; 378 cn_tp = cndev->si_tty; 379 physdev = (dev == cn_devfsdev) ? cndev : dev; 380 381 /* 382 * act appropriatly depending on whether it's /dev/console 383 * or the pysical device (e.g. /dev/sio) that's being closed. 384 * in either case, don't actually close the device unless 385 * both are closed. 386 */ 387 if (dev == cndev) { 388 /* the physical device is about to be closed */ 389 cn_phys_is_open = 0; 390 if (cn_is_open) { 391 if (cn_tp) { 392 /* perform a ttyhalfclose() */ 393 /* reset session and proc group */ 394 ttyclearsession(cn_tp); 395 } 396 return(0); 397 } 398 } else if (physdev == cndev) { 399 /* the logical console is about to be closed */ 400 cn_is_open = 0; 401 if (cn_phys_is_open) 402 return(0); 403 dev = cndev; 404 } 405 if (cn_fwd_ops) { 406 ap->a_head.a_dev = dev; 407 return (dev_doperate_ops(cn_fwd_ops, &ap->a_head)); 408 } 409 return (0); 410 } 411 412 /* 413 * The following functions are dispatched solely from the /dev/console 414 * device. Their job is primarily to forward the request through. 415 * If the console is not attached to anything then write()'s are sunk 416 * to null and reads return 0 (mostly). 417 */ 418 static int 419 cnread(struct dev_read_args *ap) 420 { 421 if (cn_tab == NULL || cn_fwd_ops == NULL) 422 return (0); 423 ap->a_head.a_dev = cn_tab->cn_dev; 424 return (dev_doperate(&ap->a_head)); 425 } 426 427 static int 428 cnwrite(struct dev_write_args *ap) 429 { 430 struct uio *uio = ap->a_uio; 431 cdev_t dev; 432 433 if (cn_tab == NULL || cn_fwd_ops == NULL) { 434 uio->uio_resid = 0; /* dump the data */ 435 return (0); 436 } 437 if (constty) 438 dev = constty->t_dev; 439 else 440 dev = cn_tab->cn_dev; 441 log_console(uio); 442 ap->a_head.a_dev = dev; 443 return (dev_doperate(&ap->a_head)); 444 } 445 446 static int 447 cnioctl(struct dev_ioctl_args *ap) 448 { 449 int error; 450 451 if (cn_tab == NULL || cn_fwd_ops == NULL) 452 return (0); 453 KKASSERT(curproc != NULL); 454 /* 455 * Superuser can always use this to wrest control of console 456 * output from the "virtual" console. 457 */ 458 if (ap->a_cmd == TIOCCONS && constty) { 459 if (ap->a_cred) { 460 error = priv_check_cred(ap->a_cred, PRIV_ROOT, 0); 461 if (error) 462 return (error); 463 } 464 constty = NULL; 465 return (0); 466 } 467 ap->a_head.a_dev = cn_tab->cn_dev; 468 return (dev_doperate(&ap->a_head)); 469 } 470 471 static int 472 cnkqfilter(struct dev_kqfilter_args *ap) 473 { 474 if ((cn_tab == NULL) || cn_mute || cn_fwd_ops == NULL) 475 return (1); 476 ap->a_head.a_dev = cn_tab->cn_dev; 477 return (dev_doperate(&ap->a_head)); 478 } 479 480 /* 481 * These synchronous functions are primarily used the kernel needs to 482 * access the keyboard (e.g. when running the debugger), or output data 483 * directly to the console. 484 */ 485 int 486 cngetc(void) 487 { 488 int c; 489 if ((cn_tab == NULL) || cn_mute) 490 return (-1); 491 c = (*cn_tab->cn_getc)(cn_tab->cn_dev); 492 if (c == '\r') c = '\n'; /* console input is always ICRNL */ 493 return (c); 494 } 495 496 int 497 cncheckc(void) 498 { 499 if ((cn_tab == NULL) || cn_mute) 500 return (-1); 501 return ((*cn_tab->cn_checkc)(cn_tab->cn_dev)); 502 } 503 504 void 505 cnputc(int c) 506 { 507 char *cp; 508 509 if ((cn_tab == NULL) || cn_mute) 510 return; 511 if (c) { 512 if (c == '\n') 513 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 514 (*cn_tab->cn_putc)(cn_tab->cn_dev, c); 515 #ifdef DDB 516 if (console_pausing && !db_active && (c == '\n')) { 517 #else 518 if (console_pausing && (c == '\n')) { 519 #endif 520 for(cp=console_pausestr; *cp != '\0'; cp++) 521 (*cn_tab->cn_putc)(cn_tab->cn_dev, *cp); 522 if (cngetc() == '.') 523 console_pausing = 0; 524 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 525 for(cp=console_pausestr; *cp != '\0'; cp++) 526 (*cn_tab->cn_putc)(cn_tab->cn_dev, ' '); 527 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 528 } 529 } 530 } 531 532 void 533 cndbctl(int on) 534 { 535 static int refcount; 536 537 if (cn_tab == NULL) 538 return; 539 if (!on) 540 refcount--; 541 if (refcount == 0 && cn_tab->cn_dbctl != NULL) 542 (*cn_tab->cn_dbctl)(cn_tab->cn_dev, on); 543 if (on) 544 refcount++; 545 } 546 547 static void 548 cn_drvinit(void *unused) 549 { 550 cn_devfsdev = make_only_devfs_dev(&cn_ops, 0, UID_ROOT, GID_WHEEL, 551 0600, "console"); 552 } 553 554 SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL) 555