/* * Copyright (c) 1988 University of Utah. * Copyright (c) 1991 The Regents of the University of California. * All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * from: @(#)cons.c 7.2 (Berkeley) 5/9/91 * $FreeBSD: src/sys/kern/tty_cons.c,v 1.81.2.4 2001/12/17 18:44:41 guido Exp $ */ #include "opt_ddb.h" #include "opt_comconsole.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static d_open_t cnopen; static d_close_t cnclose; static d_read_t cnread; static d_write_t cnwrite; static d_ioctl_t cnioctl; static d_kqfilter_t cnkqfilter; static int cnintercept(struct dev_generic_args *ap); #define CDEV_MAJOR 0 static struct dev_ops cn_ops = { { "console", 0, D_TTY | D_MPSAFE }, .d_open = cnopen, .d_close = cnclose, .d_read = cnread, .d_write = cnwrite, .d_ioctl = cnioctl, .d_kqfilter = cnkqfilter, }; static struct dev_ops cn_iops = { { "intercept", 0, D_TTY | D_MPSAFE }, .d_default = cnintercept }; static struct dev_ops *cn_fwd_ops; static cdev_t cn_dev; //XXX: get this shit out! (alexh) #if 0 SYSCTL_OPAQUE(_machdep, CPU_CONSDEV, consdev, CTLFLAG_RD, &cn_udev, sizeof cn_udev, "T,udev_t", ""); #endif static int cn_mute; #ifdef BREAK_TO_DEBUGGER int break_to_debugger = 1; /* CTL-ALT-ESC on system keyboard */ #else int break_to_debugger = 0; #endif TUNABLE_INT("kern.break_to_debugger", &break_to_debugger); SYSCTL_INT(_kern, OID_AUTO, break_to_debugger, CTLFLAG_RW, &break_to_debugger, 0, ""); #ifdef ALT_BREAK_TO_DEBUGGER int alt_break_to_debugger = 1; /* CR ~ ^B on serial port */ #else int alt_break_to_debugger = 0; #endif TUNABLE_INT("kern.alt_break_to_debugger", &alt_break_to_debugger); SYSCTL_INT(_kern, OID_AUTO, alt_break_to_debugger, CTLFLAG_RW, &alt_break_to_debugger, 0, ""); int cons_unavail = 0; /* XXX: * physical console not available for * input (i.e., it is in graphics mode) */ int sysbeep_enable = 1; static u_char cn_is_open; /* nonzero if logical console is open */ static int openmode, openflag; /* how /dev/console was openned */ static cdev_t cn_devfsdev; /* represents the device private info */ static u_char cn_phys_is_open; /* nonzero if physical device is open */ static u_char console_pausing; /* pause after each line during probe */ static char *console_pausestr= ""; struct consdev *cn_tab; /* physical console device info */ struct consdev *gdb_tab; /* physical gdb debugger device info */ SYSCTL_INT(_kern, OID_AUTO, sysbeep_enable, CTLFLAG_RW, &sysbeep_enable, 0, ""); static uint32_t console_rdev; SYSCTL_INT(_kern, OID_AUTO, console_rdev, CTLFLAG_RW, &console_rdev, 0, ""); CONS_DRIVER(cons, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL); SET_DECLARE(cons_set, struct consdev); void cninit(void) { struct consdev *best_cp, *cp, **list; /* * Workaround for token acquisition and releases during the * console init. For some reason if lwkt_gettoken()'s mpcount * optimization is turned off the console init blows up. It * might be trying to kprintf() something in the middle of * its init. */ lwkt_gettoken(&tty_token); lwkt_gettoken(&vga_token); /* * Check if we should mute the console (for security reasons perhaps) * It can be changes dynamically using sysctl kern.consmute * once we are up and going. * */ cn_mute = ((boothowto & (RB_MUTE |RB_SINGLE |RB_VERBOSE |RB_ASKNAME)) == RB_MUTE); /* * Find the first console with the highest priority. */ best_cp = NULL; SET_FOREACH(list, cons_set) { cp = *list; if (cp->cn_probe == NULL) continue; (*cp->cn_probe)(cp); if (cp->cn_pri > CN_DEAD && cp->cn_probegood && (best_cp == NULL || cp->cn_pri > best_cp->cn_pri)) best_cp = cp; } /* * If no console, give up. */ if (best_cp == NULL) { if (cn_tab != NULL && cn_tab->cn_term != NULL) (*cn_tab->cn_term)(cn_tab); goto done; } /* * Initialize console, then attach to it. This ordering allows * debugging using the previous console, if any. */ (*best_cp->cn_init)(best_cp); if (cn_tab != NULL && cn_tab != best_cp) { /* Turn off the previous console. */ if (cn_tab->cn_term != NULL) (*cn_tab->cn_term)(cn_tab); } if (boothowto & RB_PAUSE) console_pausing = 1; done: cn_tab = best_cp; /* * We can safely release the token after the init is done. * Also assert that the mpcount is still correct or otherwise * the SMP/AP boot will blow up on us. */ lwkt_reltoken(&vga_token); lwkt_reltoken(&tty_token); } /* * Hook the open and close functions on the selected device. */ void cninit_finish(void) { if ((cn_tab == NULL) || cn_mute) return; if (cn_tab->cn_dev == NULL) { cn_tab->cn_init_fini(cn_tab); if (cn_tab->cn_dev == NULL) { kprintf("Unable to hook console! cn_tab %p\n", cn_tab); return; } } cn_fwd_ops = dev_ops_intercept(cn_tab->cn_dev, &cn_iops); cn_dev = cn_tab->cn_dev; if (cn_dev) { console_rdev = makeudev(cn_dev->si_umajor, (cn_dev->si_uminor == 255 ? 0 : cn_dev->si_uminor)); } else { console_rdev = 0; } console_pausing = 0; } static void cnuninit(void) { if (cn_tab == NULL) return; if (cn_fwd_ops) dev_ops_restore(cn_tab->cn_dev, cn_fwd_ops); cn_fwd_ops = NULL; cn_dev = NULL; } /* * User has changed the state of the console muting. * This may require us to open or close the device in question. */ static int sysctl_kern_consmute(SYSCTL_HANDLER_ARGS) { int error; int ocn_mute; ocn_mute = cn_mute; error = sysctl_handle_int(oidp, &cn_mute, 0, req); if((error == 0) && (cn_tab != NULL) && (req->newptr != NULL)) { if(ocn_mute && !cn_mute) { /* * going from muted to unmuted.. open the physical dev * if the console has been openned */ cninit_finish(); if (cn_is_open) { /* XXX curproc is not what we want really */ error = dev_dopen(cn_dev, openflag, openmode, curproc->p_ucred, NULL, NULL); } /* if it failed, back it out */ if ( error != 0) cnuninit(); } else if (!ocn_mute && cn_mute) { /* * going from unmuted to muted.. close the physical dev * if it's only open via /dev/console */ if (cn_is_open) { error = dev_dclose(cn_dev, openflag, openmode, NULL); } if (error == 0) cnuninit(); } if (error != 0) { /* * back out the change if there was an error */ cn_mute = ocn_mute; } } return (error); } SYSCTL_PROC(_kern, OID_AUTO, consmute, CTLTYPE_INT|CTLFLAG_RW, 0, sizeof cn_mute, sysctl_kern_consmute, "I", ""); /* * We intercept the OPEN and CLOSE calls on the original device, and * forward the rest through. */ static int cnintercept(struct dev_generic_args *ap) { int error; if (ap->a_desc == &dev_open_desc) { error = cnopen((struct dev_open_args *)ap); } else if (ap->a_desc == &dev_close_desc) { error = cnclose((struct dev_close_args *)ap); } else if (cn_fwd_ops) { error = dev_doperate_ops(cn_fwd_ops, ap); } else { error = ENXIO; } return (error); } /* * cnopen() is called as an intercept function (dev will be that of the * actual physical device representing our console), and also called from * the muting code and from the /dev/console switch (dev will have the * console's cdevsw). */ static int cnopen(struct dev_open_args *ap) { cdev_t dev = ap->a_head.a_dev; int flag = ap->a_oflags; int mode = ap->a_devtype; cdev_t cndev; cdev_t physdev; int retval = 0; /* * Disallow access to disk volumes if RESTRICTEDROOT */ if (caps_priv_check_self(SYSCAP_RESTRICTEDROOT)) return (EPERM); if (cn_tab == NULL || cn_fwd_ops == NULL) return (0); cndev = cn_tab->cn_dev; /* actual physical device */ physdev = (dev == cn_devfsdev) ? cndev : dev; /* * If mute is active, then non console opens don't get here * so we don't need to check for that. They bypass this and go * straight to the device. * * It is important to note that due to our intercept and the fact * that we might be called via the original (intercepted) device, * the original device's ops may point to us, so to avoid an * infinite recursion we have to forward through cn_fwd_ops. * This is a severe hack that really needs to be fixed XXX. * * XXX at the moment we assume that the port forwarding function * is synchronous for open. */ if (!cn_mute) { ap->a_head.a_dev = physdev; retval = dev_doperate_ops(cn_fwd_ops, &ap->a_head); } if (retval == 0) { /* * check if we openned it via /dev/console or * via the physical entry (e.g. /dev/sio0). */ if (dev == cndev) { cn_phys_is_open = 1; } else if (physdev == cndev) { openmode = mode; openflag = flag; cn_is_open = 1; } dev->si_tty = cndev->si_tty; } return (retval); } /* * cnclose() is called as a port intercept function (dev will be that of the * actual physical device representing our console), and also called from * the muting code and from the /dev/console switch (dev will have the * console's cdevsw). */ static int cnclose(struct dev_close_args *ap) { struct tty *cn_tp; cdev_t cndev; cdev_t physdev; cdev_t dev = ap->a_head.a_dev; if (cn_tab == NULL || cn_fwd_ops == NULL) return(0); cndev = cn_tab->cn_dev; cn_tp = cndev->si_tty; physdev = (dev == cn_devfsdev) ? cndev : dev; /* * act appropriatly depending on whether it's /dev/console * or the pysical device (e.g. /dev/sio) that's being closed. * in either case, don't actually close the device unless * both are closed. */ if (dev == cndev) { /* the physical device is about to be closed */ cn_phys_is_open = 0; if (cn_is_open) { if (cn_tp) { /* perform a ttyhalfclose() */ /* reset session and proc group */ ttyclearsession(cn_tp); } return(0); } } else if (physdev == cndev) { /* the logical console is about to be closed */ cn_is_open = 0; if (cn_phys_is_open) return(0); dev = cndev; } if (cn_fwd_ops) { ap->a_head.a_dev = dev; return (dev_doperate_ops(cn_fwd_ops, &ap->a_head)); } return (0); } /* * The following functions are dispatched solely from the /dev/console * device. Their job is primarily to forward the request through. * If the console is not attached to anything then write()'s are sunk * to null and reads return 0 (mostly). */ static int cnread(struct dev_read_args *ap) { if (cn_tab == NULL || cn_fwd_ops == NULL) return (0); ap->a_head.a_dev = cn_tab->cn_dev; return (dev_doperate(&ap->a_head)); } static int cnwrite(struct dev_write_args *ap) { struct uio *uio = ap->a_uio; cdev_t dev; if (cn_tab == NULL || cn_fwd_ops == NULL) { uio->uio_resid = 0; /* dump the data */ return (0); } if (constty) dev = constty->t_dev; else dev = cn_tab->cn_dev; log_console(uio); ap->a_head.a_dev = dev; return (dev_doperate(&ap->a_head)); } static int cnioctl(struct dev_ioctl_args *ap) { int error; if (cn_tab == NULL || cn_fwd_ops == NULL) return (0); KKASSERT(curproc != NULL); /* * Superuser can always use this to wrest control of console * output from the "virtual" console. */ if (ap->a_cmd == TIOCCONS && constty) { if (ap->a_cred) { error = caps_priv_check(ap->a_cred, SYSCAP_RESTRICTEDROOT); if (error) return (error); } constty = NULL; return (0); } ap->a_head.a_dev = cn_tab->cn_dev; return (dev_doperate(&ap->a_head)); } static int cnkqfilter(struct dev_kqfilter_args *ap) { if ((cn_tab == NULL) || cn_mute || cn_fwd_ops == NULL) return (1); ap->a_head.a_dev = cn_tab->cn_dev; return (dev_doperate(&ap->a_head)); } /* * These synchronous functions are primarily used the kernel needs to * access the keyboard (e.g. when running the debugger), or output data * directly to the console. */ int cngetc(void) { int c; if ((cn_tab == NULL) || cn_mute) return (-1); c = (*cn_tab->cn_getc)(cn_tab->cn_private); if (c == '\r') c = '\n'; /* console input is always ICRNL */ return (c); } int cncheckc(void) { if ((cn_tab == NULL) || cn_mute) return (-1); return ((*cn_tab->cn_checkc)(cn_tab->cn_private)); } void cnpoll(int on) { if ((cn_tab == NULL) || cn_mute) return; if (cn_tab->cn_poll) ((*cn_tab->cn_poll)(cn_tab->cn_private, on)); } void cnputc(int c) { char *cp; if ((cn_tab == NULL) || cn_mute) return; if (c) { if (c == '\n') (*cn_tab->cn_putc)(cn_tab->cn_private, '\r'); (*cn_tab->cn_putc)(cn_tab->cn_private, c); #ifdef DDB if (console_pausing && !db_active && (c == '\n')) { #else if (console_pausing && (c == '\n')) { #endif for(cp=console_pausestr; *cp != '\0'; cp++) (*cn_tab->cn_putc)(cn_tab->cn_private, *cp); if (cngetc() == '.') console_pausing = 0; (*cn_tab->cn_putc)(cn_tab->cn_private, '\r'); for(cp=console_pausestr; *cp != '\0'; cp++) (*cn_tab->cn_putc)(cn_tab->cn_private, ' '); (*cn_tab->cn_putc)(cn_tab->cn_private, '\r'); } } } void cndbctl(int on) { static int refcount; if (cn_tab == NULL) return; if (!on) refcount--; if (refcount == 0 && cn_tab->cn_dbctl != NULL) (*cn_tab->cn_dbctl)(cn_tab->cn_private, on); if (on) refcount++; } static void cn_drvinit(void *unused) { cn_devfsdev = make_only_devfs_dev(&cn_ops, 0, UID_ROOT, GID_WHEEL, 0600, "console"); } SYSINIT(cndev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE + CDEV_MAJOR, cn_drvinit, NULL);