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 * $DragonFly: src/sys/kern/tty_cons.c,v 1.2 2003/06/17 04:28:41 dillon Exp $ 41 */ 42 43 #include "opt_ddb.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/conf.h> 48 #include <sys/cons.h> 49 #include <sys/kernel.h> 50 #include <sys/proc.h> 51 #include <sys/reboot.h> 52 #include <sys/sysctl.h> 53 #include <sys/tty.h> 54 #include <sys/uio.h> 55 56 #include <ddb/ddb.h> 57 58 #include <machine/cpu.h> 59 60 static d_open_t cnopen; 61 static d_close_t cnclose; 62 static d_read_t cnread; 63 static d_write_t cnwrite; 64 static d_ioctl_t cnioctl; 65 static d_poll_t cnpoll; 66 static d_kqfilter_t cnkqfilter; 67 68 #define CDEV_MAJOR 0 69 static struct cdevsw cn_cdevsw = { 70 /* open */ cnopen, 71 /* close */ cnclose, 72 /* read */ cnread, 73 /* write */ cnwrite, 74 /* ioctl */ cnioctl, 75 /* poll */ cnpoll, 76 /* mmap */ nommap, 77 /* strategy */ nostrategy, 78 /* name */ "console", 79 /* maj */ CDEV_MAJOR, 80 /* dump */ nodump, 81 /* psize */ nopsize, 82 /* flags */ D_TTY | D_KQFILTER, 83 /* bmaj */ -1, 84 /* kqfilter */ cnkqfilter, 85 }; 86 87 static dev_t cn_dev_t; /* seems to be never really used */ 88 static udev_t cn_udev_t; 89 SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD, 90 &cn_udev_t, sizeof cn_udev_t, "T,dev_t", ""); 91 92 static int cn_mute; 93 94 int cons_unavail = 0; /* XXX: 95 * physical console not available for 96 * input (i.e., it is in graphics mode) 97 */ 98 99 static u_char cn_is_open; /* nonzero if logical console is open */ 100 static int openmode, openflag; /* how /dev/console was openned */ 101 static dev_t cn_devfsdev; /* represents the device private info */ 102 static u_char cn_phys_is_open; /* nonzero if physical device is open */ 103 static d_close_t *cn_phys_close; /* physical device close function */ 104 static d_open_t *cn_phys_open; /* physical device open function */ 105 struct consdev *cn_tab; /* physical console device info */ 106 static u_char console_pausing; /* pause after each line during probe */ 107 static char *console_pausestr= 108 "<pause; press any key to proceed to next line or '.' to end pause mode>"; 109 110 CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL); 111 112 void 113 cninit() 114 { 115 struct consdev *best_cp, *cp, **list; 116 117 /* 118 * Find the first console with the highest priority. 119 */ 120 best_cp = NULL; 121 list = (struct consdev **)cons_set.ls_items; 122 while ((cp = *list++) != NULL) { 123 if (cp->cn_probe == NULL) 124 continue; 125 (*cp->cn_probe)(cp); 126 if (cp->cn_pri > CN_DEAD && 127 (best_cp == NULL || cp->cn_pri > best_cp->cn_pri)) 128 best_cp = cp; 129 } 130 131 /* 132 * Check if we should mute the console (for security reasons perhaps) 133 * It can be changes dynamically using sysctl kern.consmute 134 * once we are up and going. 135 * 136 */ 137 cn_mute = ((boothowto & (RB_MUTE 138 |RB_SINGLE 139 |RB_VERBOSE 140 |RB_ASKNAME 141 |RB_CONFIG)) == RB_MUTE); 142 143 /* 144 * If no console, give up. 145 */ 146 if (best_cp == NULL) { 147 if (cn_tab != NULL && cn_tab->cn_term != NULL) 148 (*cn_tab->cn_term)(cn_tab); 149 cn_tab = best_cp; 150 return; 151 } 152 153 /* 154 * Initialize console, then attach to it. This ordering allows 155 * debugging using the previous console, if any. 156 */ 157 (*best_cp->cn_init)(best_cp); 158 if (cn_tab != NULL && cn_tab != best_cp) { 159 /* Turn off the previous console. */ 160 if (cn_tab->cn_term != NULL) 161 (*cn_tab->cn_term)(cn_tab); 162 } 163 if (boothowto & RB_PAUSE) 164 console_pausing = 1; 165 cn_tab = best_cp; 166 } 167 168 void 169 cninit_finish() 170 { 171 struct cdevsw *cdp; 172 173 if ((cn_tab == NULL) || cn_mute) 174 return; 175 176 /* 177 * Hook the open and close functions. 178 */ 179 cdp = devsw(cn_tab->cn_dev); 180 if (cdp != NULL) { 181 cn_phys_close = cdp->d_close; 182 cdp->d_close = cnclose; 183 cn_phys_open = cdp->d_open; 184 cdp->d_open = cnopen; 185 } 186 cn_dev_t = cn_tab->cn_dev; 187 cn_udev_t = dev2udev(cn_dev_t); 188 console_pausing = 0; 189 } 190 191 static void 192 cnuninit(void) 193 { 194 struct cdevsw *cdp; 195 196 if (cn_tab == NULL) 197 return; 198 199 /* 200 * Unhook the open and close functions. 201 */ 202 cdp = devsw(cn_tab->cn_dev); 203 if (cdp != NULL) { 204 cdp->d_close = cn_phys_close; 205 cdp->d_open = cn_phys_open; 206 } 207 cn_phys_close = NULL; 208 cn_phys_open = NULL; 209 cn_dev_t = NODEV; 210 cn_udev_t = NOUDEV; 211 } 212 213 /* 214 * User has changed the state of the console muting. 215 * This may require us to open or close the device in question. 216 */ 217 static int 218 sysctl_kern_consmute(SYSCTL_HANDLER_ARGS) 219 { 220 int error; 221 int ocn_mute; 222 223 ocn_mute = cn_mute; 224 error = sysctl_handle_int(oidp, &cn_mute, 0, req); 225 if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) { 226 if(ocn_mute && !cn_mute) { 227 /* 228 * going from muted to unmuted.. open the physical dev 229 * if the console has been openned 230 */ 231 cninit_finish(); 232 if(cn_is_open) 233 /* XXX curproc is not what we want really */ 234 error = cnopen(cn_dev_t, openflag, 235 openmode, curproc); 236 /* if it failed, back it out */ 237 if ( error != 0) cnuninit(); 238 } else if (!ocn_mute && cn_mute) { 239 /* 240 * going from unmuted to muted.. close the physical dev 241 * if it's only open via /dev/console 242 */ 243 if(cn_is_open) 244 error = cnclose(cn_dev_t, openflag, 245 openmode, curproc); 246 if ( error == 0) cnuninit(); 247 } 248 if (error != 0) { 249 /* 250 * back out the change if there was an error 251 */ 252 cn_mute = ocn_mute; 253 } 254 } 255 return (error); 256 } 257 258 SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW, 259 0, sizeof cn_mute, sysctl_kern_consmute, "I", ""); 260 261 static int 262 cnopen(dev, flag, mode, p) 263 dev_t dev; 264 int flag, mode; 265 struct proc *p; 266 { 267 dev_t cndev, physdev; 268 int retval = 0; 269 270 if (cn_tab == NULL || cn_phys_open == NULL) 271 return (0); 272 cndev = cn_tab->cn_dev; 273 physdev = (major(dev) == major(cndev) ? dev : cndev); 274 /* 275 * If mute is active, then non console opens don't get here 276 * so we don't need to check for that. They 277 * bypass this and go straight to the device. 278 */ 279 if(!cn_mute) 280 retval = (*cn_phys_open)(physdev, flag, mode, p); 281 if (retval == 0) { 282 /* 283 * check if we openned it via /dev/console or 284 * via the physical entry (e.g. /dev/sio0). 285 */ 286 if (dev == cndev) 287 cn_phys_is_open = 1; 288 else if (physdev == cndev) { 289 openmode = mode; 290 openflag = flag; 291 cn_is_open = 1; 292 } 293 dev->si_tty = physdev->si_tty; 294 } 295 return (retval); 296 } 297 298 static int 299 cnclose(dev, flag, mode, p) 300 dev_t dev; 301 int flag, mode; 302 struct proc *p; 303 { 304 dev_t cndev; 305 struct tty *cn_tp; 306 307 if (cn_tab == NULL || cn_phys_open == NULL) 308 return (0); 309 cndev = cn_tab->cn_dev; 310 cn_tp = cndev->si_tty; 311 /* 312 * act appropriatly depending on whether it's /dev/console 313 * or the pysical device (e.g. /dev/sio) that's being closed. 314 * in either case, don't actually close the device unless 315 * both are closed. 316 */ 317 if (dev == cndev) { 318 /* the physical device is about to be closed */ 319 cn_phys_is_open = 0; 320 if (cn_is_open) { 321 if (cn_tp) { 322 /* perform a ttyhalfclose() */ 323 /* reset session and proc group */ 324 cn_tp->t_pgrp = NULL; 325 cn_tp->t_session = NULL; 326 } 327 return (0); 328 } 329 } else if (major(dev) != major(cndev)) { 330 /* the logical console is about to be closed */ 331 cn_is_open = 0; 332 if (cn_phys_is_open) 333 return (0); 334 dev = cndev; 335 } 336 if(cn_phys_close) 337 return ((*cn_phys_close)(dev, flag, mode, p)); 338 return (0); 339 } 340 341 static int 342 cnread(dev, uio, flag) 343 dev_t dev; 344 struct uio *uio; 345 int flag; 346 { 347 348 if (cn_tab == NULL || cn_phys_open == NULL) 349 return (0); 350 dev = cn_tab->cn_dev; 351 return ((*devsw(dev)->d_read)(dev, uio, flag)); 352 } 353 354 static int 355 cnwrite(dev, uio, flag) 356 dev_t dev; 357 struct uio *uio; 358 int flag; 359 { 360 361 if (cn_tab == NULL || cn_phys_open == NULL) { 362 uio->uio_resid = 0; /* dump the data */ 363 return (0); 364 } 365 if (constty) 366 dev = constty->t_dev; 367 else 368 dev = cn_tab->cn_dev; 369 log_console(uio); 370 return ((*devsw(dev)->d_write)(dev, uio, flag)); 371 } 372 373 static int 374 cnioctl(dev, cmd, data, flag, p) 375 dev_t dev; 376 u_long cmd; 377 caddr_t data; 378 int flag; 379 struct proc *p; 380 { 381 int error; 382 383 if (cn_tab == NULL || cn_phys_open == NULL) 384 return (0); 385 /* 386 * Superuser can always use this to wrest control of console 387 * output from the "virtual" console. 388 */ 389 if (cmd == TIOCCONS && constty) { 390 error = suser(p); 391 if (error) 392 return (error); 393 constty = NULL; 394 return (0); 395 } 396 dev = cn_tab->cn_dev; 397 return ((*devsw(dev)->d_ioctl)(dev, cmd, data, flag, p)); 398 } 399 400 static int 401 cnpoll(dev, events, p) 402 dev_t dev; 403 int events; 404 struct proc *p; 405 { 406 if ((cn_tab == NULL) || cn_mute) 407 return (1); 408 409 dev = cn_tab->cn_dev; 410 411 return ((*devsw(dev)->d_poll)(dev, events, p)); 412 } 413 414 static int 415 cnkqfilter(dev, kn) 416 dev_t dev; 417 struct knote *kn; 418 { 419 if ((cn_tab == NULL) || cn_mute) 420 return (1); 421 422 dev = cn_tab->cn_dev; 423 if (devsw(dev)->d_flags & D_KQFILTER) 424 return ((*devsw(dev)->d_kqfilter)(dev, kn)); 425 return (1); 426 } 427 428 int 429 cngetc() 430 { 431 int c; 432 if ((cn_tab == NULL) || cn_mute) 433 return (-1); 434 c = (*cn_tab->cn_getc)(cn_tab->cn_dev); 435 if (c == '\r') c = '\n'; /* console input is always ICRNL */ 436 return (c); 437 } 438 439 int 440 cncheckc() 441 { 442 if ((cn_tab == NULL) || cn_mute) 443 return (-1); 444 return ((*cn_tab->cn_checkc)(cn_tab->cn_dev)); 445 } 446 447 void 448 cnputc(c) 449 register int c; 450 { 451 char *cp; 452 453 if ((cn_tab == NULL) || cn_mute) 454 return; 455 if (c) { 456 if (c == '\n') 457 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 458 (*cn_tab->cn_putc)(cn_tab->cn_dev, c); 459 #ifdef DDB 460 if (console_pausing && !db_active && (c == '\n')) { 461 #else 462 if (console_pausing && (c == '\n')) { 463 #endif 464 for(cp=console_pausestr; *cp != '\0'; cp++) 465 (*cn_tab->cn_putc)(cn_tab->cn_dev, *cp); 466 if (cngetc() == '.') 467 console_pausing = 0; 468 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 469 for(cp=console_pausestr; *cp != '\0'; cp++) 470 (*cn_tab->cn_putc)(cn_tab->cn_dev, ' '); 471 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r'); 472 } 473 } 474 } 475 476 void 477 cndbctl(on) 478 int on; 479 { 480 static int refcount; 481 482 if (cn_tab == NULL) 483 return; 484 if (!on) 485 refcount--; 486 if (refcount == 0 && cn_tab->cn_dbctl != NULL) 487 (*cn_tab->cn_dbctl)(cn_tab->cn_dev, on); 488 if (on) 489 refcount++; 490 } 491 492 static void 493 cn_drvinit(void *unused) 494 { 495 496 cn_devfsdev = make_dev(&cn_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, 497 "console"); 498 } 499 500 SYSINIT(cndev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,cn_drvinit,NULL) 501