tty_ptm.c revision 1.2.2.2
1 1.2.2.2 skrll /* $NetBSD: tty_ptm.c,v 1.2.2.2 2004/11/14 08:15:57 skrll Exp $ */ 2 1.2.2.2 skrll 3 1.2.2.2 skrll /*- 4 1.2.2.2 skrll * Copyright (c) 2004 The NetBSD Foundation, Inc. 5 1.2.2.2 skrll * All rights reserved. 6 1.2.2.2 skrll * 7 1.2.2.2 skrll * Redistribution and use in source and binary forms, with or without 8 1.2.2.2 skrll * modification, are permitted provided that the following conditions 9 1.2.2.2 skrll * are met: 10 1.2.2.2 skrll * 1. Redistributions of source code must retain the above copyright 11 1.2.2.2 skrll * notice, this list of conditions and the following disclaimer. 12 1.2.2.2 skrll * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.2.2 skrll * notice, this list of conditions and the following disclaimer in the 14 1.2.2.2 skrll * documentation and/or other materials provided with the distribution. 15 1.2.2.2 skrll * 3. All advertising materials mentioning features or use of this software 16 1.2.2.2 skrll * must display the following acknowledgement: 17 1.2.2.2 skrll * This product includes software developed by the NetBSD 18 1.2.2.2 skrll * Foundation, Inc. and its contributors. 19 1.2.2.2 skrll * 4. Neither the name of The NetBSD Foundation nor the names of its 20 1.2.2.2 skrll * contributors may be used to endorse or promote products derived 21 1.2.2.2 skrll * from this software without specific prior written permission. 22 1.2.2.2 skrll * 23 1.2.2.2 skrll * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 24 1.2.2.2 skrll * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 25 1.2.2.2 skrll * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 26 1.2.2.2 skrll * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 27 1.2.2.2 skrll * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 28 1.2.2.2 skrll * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29 1.2.2.2 skrll * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30 1.2.2.2 skrll * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31 1.2.2.2 skrll * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32 1.2.2.2 skrll * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 1.2.2.2 skrll * POSSIBILITY OF SUCH DAMAGE. 34 1.2.2.2 skrll */ 35 1.2.2.2 skrll 36 1.2.2.2 skrll #include <sys/cdefs.h> 37 1.2.2.2 skrll __KERNEL_RCSID(0, "$NetBSD: tty_ptm.c,v 1.2.2.2 2004/11/14 08:15:57 skrll Exp $"); 38 1.2.2.2 skrll 39 1.2.2.2 skrll #include "opt_ptm.h" 40 1.2.2.2 skrll 41 1.2.2.2 skrll /* pty multiplexor driver /dev/ptm{,x} */ 42 1.2.2.2 skrll 43 1.2.2.2 skrll #include <sys/param.h> 44 1.2.2.2 skrll #include <sys/systm.h> 45 1.2.2.2 skrll #include <sys/ioctl.h> 46 1.2.2.2 skrll #include <sys/proc.h> 47 1.2.2.2 skrll #include <sys/tty.h> 48 1.2.2.2 skrll #include <sys/stat.h> 49 1.2.2.2 skrll #include <sys/file.h> 50 1.2.2.2 skrll #include <sys/uio.h> 51 1.2.2.2 skrll #include <sys/kernel.h> 52 1.2.2.2 skrll #include <sys/vnode.h> 53 1.2.2.2 skrll #include <sys/namei.h> 54 1.2.2.2 skrll #include <sys/signalvar.h> 55 1.2.2.2 skrll #include <sys/uio.h> 56 1.2.2.2 skrll #include <sys/filedesc.h> 57 1.2.2.2 skrll #include <sys/conf.h> 58 1.2.2.2 skrll #include <sys/poll.h> 59 1.2.2.2 skrll #include <sys/malloc.h> 60 1.2.2.2 skrll #include <sys/pty.h> 61 1.2.2.2 skrll 62 1.2.2.2 skrll #ifdef DEBUG_PTM 63 1.2.2.2 skrll #define DPRINTF(a) printf a 64 1.2.2.2 skrll #else 65 1.2.2.2 skrll #define DPRINTF(a) 66 1.2.2.2 skrll #endif 67 1.2.2.2 skrll 68 1.2.2.2 skrll #ifdef NO_DEV_PTM 69 1.2.2.2 skrll const struct cdevsw ptm_cdevsw = { 70 1.2.2.2 skrll noopen, noclose, noread, nowrite, noioctl, 71 1.2.2.2 skrll nostop, notty, nopoll, nommap, nokqfilter, D_TTY 72 1.2.2.2 skrll }; 73 1.2.2.2 skrll #else 74 1.2.2.2 skrll 75 1.2.2.2 skrll static struct ptm_pty *ptm; 76 1.2.2.2 skrll int pts_major, ptc_major; 77 1.2.2.2 skrll 78 1.2.2.2 skrll static dev_t pty_getfree(void); 79 1.2.2.2 skrll static int pty_alloc_master(struct lwp *, int *, dev_t *); 80 1.2.2.2 skrll static int pty_alloc_slave(struct lwp *, int *, dev_t); 81 1.2.2.2 skrll 82 1.2.2.2 skrll void ptmattach(int); 83 1.2.2.2 skrll 84 1.2.2.2 skrll dev_type_open(ptmopen); 85 1.2.2.2 skrll dev_type_close(ptmclose); 86 1.2.2.2 skrll dev_type_ioctl(ptmioctl); 87 1.2.2.2 skrll 88 1.2.2.2 skrll const struct cdevsw ptm_cdevsw = { 89 1.2.2.2 skrll ptmopen, ptmclose, noread, nowrite, ptmioctl, 90 1.2.2.2 skrll nullstop, notty, nopoll, nommap, nokqfilter, D_TTY 91 1.2.2.2 skrll }; 92 1.2.2.2 skrll 93 1.2.2.2 skrll dev_t 94 1.2.2.2 skrll pty_makedev(char ms, int minor) 95 1.2.2.2 skrll { 96 1.2.2.2 skrll return makedev(ms == 't' ? pts_major : ptc_major, minor); 97 1.2.2.2 skrll } 98 1.2.2.2 skrll 99 1.2.2.2 skrll static dev_t 100 1.2.2.2 skrll pty_getfree(void) 101 1.2.2.2 skrll { 102 1.2.2.2 skrll extern struct simplelock pt_softc_mutex; 103 1.2.2.2 skrll int i; 104 1.2.2.2 skrll 105 1.2.2.2 skrll simple_lock(&pt_softc_mutex); 106 1.2.2.2 skrll for (i = 0; i < npty; i++) { 107 1.2.2.2 skrll if (pty_isfree(i, 0)) 108 1.2.2.2 skrll break; 109 1.2.2.2 skrll } 110 1.2.2.2 skrll simple_unlock(&pt_softc_mutex); 111 1.2.2.2 skrll return pty_makedev('t', i); 112 1.2.2.2 skrll } 113 1.2.2.2 skrll 114 1.2.2.2 skrll /* 115 1.2.2.2 skrll * Hacked up version of vn_open. We _only_ handle ptys and only open 116 1.2.2.2 skrll * them with FREAD|FWRITE and never deal with creat or stuff like that. 117 1.2.2.2 skrll * 118 1.2.2.2 skrll * We need it because we have to fake up root credentials to open the pty. 119 1.2.2.2 skrll */ 120 1.2.2.2 skrll int 121 1.2.2.2 skrll pty_vn_open(struct vnode *vp, struct lwp *l) 122 1.2.2.2 skrll { 123 1.2.2.2 skrll struct ucred *cred; 124 1.2.2.2 skrll int error; 125 1.2.2.2 skrll 126 1.2.2.2 skrll if (vp->v_type != VCHR) { 127 1.2.2.2 skrll vput(vp); 128 1.2.2.2 skrll return EINVAL; 129 1.2.2.2 skrll } 130 1.2.2.2 skrll 131 1.2.2.2 skrll /* 132 1.2.2.2 skrll * Get us a fresh cred with root privileges. 133 1.2.2.2 skrll */ 134 1.2.2.2 skrll cred = crget(); 135 1.2.2.2 skrll error = VOP_OPEN(vp, FREAD|FWRITE, cred, l); 136 1.2.2.2 skrll crfree(cred); 137 1.2.2.2 skrll 138 1.2.2.2 skrll if (error) { 139 1.2.2.2 skrll vput(vp); 140 1.2.2.2 skrll return error; 141 1.2.2.2 skrll } 142 1.2.2.2 skrll 143 1.2.2.2 skrll vp->v_writecount++; 144 1.2.2.2 skrll 145 1.2.2.2 skrll return 0; 146 1.2.2.2 skrll } 147 1.2.2.2 skrll 148 1.2.2.2 skrll static int 149 1.2.2.2 skrll pty_alloc_master(struct lwp *l, int *fd, dev_t *dev) 150 1.2.2.2 skrll { 151 1.2.2.2 skrll int error; 152 1.2.2.2 skrll struct file *fp; 153 1.2.2.2 skrll struct vnode *vp; 154 1.2.2.2 skrll struct proc *p = l->l_proc; 155 1.2.2.2 skrll int md; 156 1.2.2.2 skrll 157 1.2.2.2 skrll if ((error = falloc(p, &fp, fd)) != 0) { 158 1.2.2.2 skrll DPRINTF(("falloc %d\n", error)); 159 1.2.2.2 skrll return error; 160 1.2.2.2 skrll } 161 1.2.2.2 skrll retry: 162 1.2.2.2 skrll /* Find and open a free master pty. */ 163 1.2.2.2 skrll *dev = pty_getfree(); 164 1.2.2.2 skrll md = minor(*dev); 165 1.2.2.2 skrll if ((error = pty_check(md)) != 0) { 166 1.2.2.2 skrll DPRINTF(("pty_check %d\n", error)); 167 1.2.2.2 skrll goto bad; 168 1.2.2.2 skrll } 169 1.2.2.2 skrll if (ptm == NULL) { 170 1.2.2.2 skrll error = EOPNOTSUPP; 171 1.2.2.2 skrll goto bad; 172 1.2.2.2 skrll } 173 1.2.2.2 skrll if ((error = (*ptm->allocvp)(ptm, l, &vp, *dev, 'p')) != 0) 174 1.2.2.2 skrll goto bad; 175 1.2.2.2 skrll 176 1.2.2.2 skrll if ((error = pty_vn_open(vp, l)) != 0) { 177 1.2.2.2 skrll /* 178 1.2.2.2 skrll * Check if the master open failed because we lost 179 1.2.2.2 skrll * the race to grab it. 180 1.2.2.2 skrll */ 181 1.2.2.2 skrll if (error != EIO) 182 1.2.2.2 skrll goto bad; 183 1.2.2.2 skrll error = !pty_isfree(md, 1); 184 1.2.2.2 skrll if (error) 185 1.2.2.2 skrll goto retry; 186 1.2.2.2 skrll else 187 1.2.2.2 skrll goto bad; 188 1.2.2.2 skrll } 189 1.2.2.2 skrll fp->f_flag = FREAD|FWRITE; 190 1.2.2.2 skrll fp->f_type = DTYPE_VNODE; 191 1.2.2.2 skrll fp->f_ops = &vnops; 192 1.2.2.2 skrll fp->f_data = vp; 193 1.2.2.2 skrll VOP_UNLOCK(vp, 0); 194 1.2.2.2 skrll FILE_SET_MATURE(fp); 195 1.2.2.2 skrll FILE_UNUSE(fp, l); 196 1.2.2.2 skrll return 0; 197 1.2.2.2 skrll bad: 198 1.2.2.2 skrll FILE_UNUSE(fp, l); 199 1.2.2.2 skrll fdremove(p->p_fd, *fd); 200 1.2.2.2 skrll ffree(fp); 201 1.2.2.2 skrll return error; 202 1.2.2.2 skrll } 203 1.2.2.2 skrll 204 1.2.2.2 skrll int 205 1.2.2.2 skrll pty_grant_slave(struct lwp *l, dev_t dev) 206 1.2.2.2 skrll { 207 1.2.2.2 skrll int error; 208 1.2.2.2 skrll struct vnode *vp; 209 1.2.2.2 skrll 210 1.2.2.2 skrll /* 211 1.2.2.2 skrll * Open the slave. 212 1.2.2.2 skrll * namei -> setattr -> unlock -> revoke -> vrele -> 213 1.2.2.2 skrll * namei -> open -> unlock 214 1.2.2.2 skrll * Three stage rocket: 215 1.2.2.2 skrll * 1. Change the owner and permissions on the slave. 216 1.2.2.2 skrll * 2. Revoke all the users of the slave. 217 1.2.2.2 skrll * 3. open the slave. 218 1.2.2.2 skrll */ 219 1.2.2.2 skrll if (ptm == NULL) 220 1.2.2.2 skrll return EOPNOTSUPP; 221 1.2.2.2 skrll 222 1.2.2.2 skrll if ((error = (*ptm->allocvp)(ptm, l, &vp, dev, 't')) != 0) 223 1.2.2.2 skrll return error; 224 1.2.2.2 skrll 225 1.2.2.2 skrll if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { 226 1.2.2.2 skrll struct vattr vattr; 227 1.2.2.2 skrll struct ucred *cred; 228 1.2.2.2 skrll /* get real uid */ 229 1.2.2.2 skrll VATTR_NULL(&vattr); 230 1.2.2.2 skrll vattr.va_uid = l->l_proc->p_cred->p_ruid; 231 1.2.2.2 skrll vattr.va_gid = _TTY_GID; 232 1.2.2.2 skrll vattr.va_mode = S_IRUSR|S_IWUSR|S_IWGRP; 233 1.2.2.2 skrll /* Get a fake cred to pretend we're root. */ 234 1.2.2.2 skrll cred = crget(); 235 1.2.2.2 skrll error = VOP_SETATTR(vp, &vattr, cred, l); 236 1.2.2.2 skrll crfree(cred); 237 1.2.2.2 skrll if (error) { 238 1.2.2.2 skrll DPRINTF(("setattr %d\n", error)); 239 1.2.2.2 skrll VOP_UNLOCK(vp, 0); 240 1.2.2.2 skrll vrele(vp); 241 1.2.2.2 skrll return error; 242 1.2.2.2 skrll } 243 1.2.2.2 skrll } 244 1.2.2.2 skrll VOP_UNLOCK(vp, 0); 245 1.2.2.2 skrll if (vp->v_usecount > 1 || 246 1.2.2.2 skrll (vp->v_flag & (VALIASED | VLAYER))) 247 1.2.2.2 skrll VOP_REVOKE(vp, REVOKEALL); 248 1.2.2.2 skrll 249 1.2.2.2 skrll /* 250 1.2.2.2 skrll * The vnode is useless after the revoke, we need to get it again. 251 1.2.2.2 skrll */ 252 1.2.2.2 skrll vrele(vp); 253 1.2.2.2 skrll return 0; 254 1.2.2.2 skrll } 255 1.2.2.2 skrll 256 1.2.2.2 skrll static int 257 1.2.2.2 skrll pty_alloc_slave(struct lwp *l, int *fd, dev_t dev) 258 1.2.2.2 skrll { 259 1.2.2.2 skrll int error; 260 1.2.2.2 skrll struct file *fp; 261 1.2.2.2 skrll struct vnode *vp; 262 1.2.2.2 skrll struct proc *p = l->l_proc; 263 1.2.2.2 skrll 264 1.2.2.2 skrll /* Grab a filedescriptor for the slave */ 265 1.2.2.2 skrll if ((error = falloc(p, &fp, fd)) != 0) { 266 1.2.2.2 skrll DPRINTF(("falloc %d\n", error)); 267 1.2.2.2 skrll return error; 268 1.2.2.2 skrll } 269 1.2.2.2 skrll 270 1.2.2.2 skrll if (ptm == NULL) { 271 1.2.2.2 skrll error = EOPNOTSUPP; 272 1.2.2.2 skrll goto bad; 273 1.2.2.2 skrll } 274 1.2.2.2 skrll 275 1.2.2.2 skrll if ((error = (*ptm->allocvp)(ptm, l, &vp, dev, 't')) != 0) 276 1.2.2.2 skrll goto bad; 277 1.2.2.2 skrll if ((error = pty_vn_open(vp, l)) != 0) 278 1.2.2.2 skrll goto bad; 279 1.2.2.2 skrll 280 1.2.2.2 skrll fp->f_flag = FREAD|FWRITE; 281 1.2.2.2 skrll fp->f_type = DTYPE_VNODE; 282 1.2.2.2 skrll fp->f_ops = &vnops; 283 1.2.2.2 skrll fp->f_data = vp; 284 1.2.2.2 skrll VOP_UNLOCK(vp, 0); 285 1.2.2.2 skrll FILE_SET_MATURE(fp); 286 1.2.2.2 skrll FILE_UNUSE(fp, l); 287 1.2.2.2 skrll return 0; 288 1.2.2.2 skrll bad: 289 1.2.2.2 skrll FILE_UNUSE(fp, l); 290 1.2.2.2 skrll fdremove(p->p_fd, *fd); 291 1.2.2.2 skrll ffree(fp); 292 1.2.2.2 skrll return error; 293 1.2.2.2 skrll } 294 1.2.2.2 skrll 295 1.2.2.2 skrll struct ptm_pty * 296 1.2.2.2 skrll pty_sethandler(struct ptm_pty *nptm) 297 1.2.2.2 skrll { 298 1.2.2.2 skrll struct ptm_pty *optm = ptm; 299 1.2.2.2 skrll ptm = nptm; 300 1.2.2.2 skrll return optm; 301 1.2.2.2 skrll } 302 1.2.2.2 skrll 303 1.2.2.2 skrll int 304 1.2.2.2 skrll pty_fill_ptmget(dev_t dev, int cfd, int sfd, void *data) 305 1.2.2.2 skrll { 306 1.2.2.2 skrll struct ptmget *ptmg = data; 307 1.2.2.2 skrll int error; 308 1.2.2.2 skrll 309 1.2.2.2 skrll if (ptm == NULL) 310 1.2.2.2 skrll return EOPNOTSUPP; 311 1.2.2.2 skrll 312 1.2.2.2 skrll ptmg->cfd = cfd == -1 ? minor(dev) : cfd; 313 1.2.2.2 skrll ptmg->sfd = sfd == -1 ? minor(dev) : sfd; 314 1.2.2.2 skrll 315 1.2.2.2 skrll error = (*ptm->makename)(ptm, ptmg->cn, sizeof(ptmg->cn), dev, 'p'); 316 1.2.2.2 skrll if (error) 317 1.2.2.2 skrll return error; 318 1.2.2.2 skrll 319 1.2.2.2 skrll return (*ptm->makename)(ptm, ptmg->sn, sizeof(ptmg->sn), dev, 't'); 320 1.2.2.2 skrll } 321 1.2.2.2 skrll 322 1.2.2.2 skrll void 323 1.2.2.2 skrll /*ARGSUSED*/ 324 1.2.2.2 skrll ptmattach(int n) 325 1.2.2.2 skrll { 326 1.2.2.2 skrll extern const struct cdevsw pts_cdevsw, ptc_cdevsw; 327 1.2.2.2 skrll /* find the major and minor of the pty devices */ 328 1.2.2.2 skrll if ((pts_major = cdevsw_lookup_major(&pts_cdevsw)) == -1) 329 1.2.2.2 skrll panic("ptmattach: Can't find pty slave in cdevsw"); 330 1.2.2.2 skrll if ((ptc_major = cdevsw_lookup_major(&ptc_cdevsw)) == -1) 331 1.2.2.2 skrll panic("ptmattach: Can't find pty master in cdevsw"); 332 1.2.2.2 skrll #ifdef COMPAT_BSDPTY 333 1.2.2.2 skrll ptm = &ptm_bsdpty; 334 1.2.2.2 skrll #endif 335 1.2.2.2 skrll } 336 1.2.2.2 skrll 337 1.2.2.2 skrll int 338 1.2.2.2 skrll /*ARGSUSED*/ 339 1.2.2.2 skrll ptmopen(dev_t dev, int flag, int mode, struct lwp *l) 340 1.2.2.2 skrll { 341 1.2.2.2 skrll int error; 342 1.2.2.2 skrll int fd; 343 1.2.2.2 skrll 344 1.2.2.2 skrll switch(minor(dev)) { 345 1.2.2.2 skrll case 0: /* /dev/ptmx */ 346 1.2.2.2 skrll if ((error = pty_alloc_master(l, &fd, &dev)) != 0) 347 1.2.2.2 skrll return error; 348 1.2.2.2 skrll curlwp->l_dupfd = fd; 349 1.2.2.2 skrll return ENXIO; 350 1.2.2.2 skrll case 1: /* /dev/ptm */ 351 1.2.2.2 skrll return 0; 352 1.2.2.2 skrll default: 353 1.2.2.2 skrll return ENODEV; 354 1.2.2.2 skrll } 355 1.2.2.2 skrll } 356 1.2.2.2 skrll 357 1.2.2.2 skrll int 358 1.2.2.2 skrll /*ARGSUSED*/ 359 1.2.2.2 skrll ptmclose(dev_t dev, int flag, int mode, struct lwp *l) 360 1.2.2.2 skrll { 361 1.2.2.2 skrll return (0); 362 1.2.2.2 skrll } 363 1.2.2.2 skrll 364 1.2.2.2 skrll int 365 1.2.2.2 skrll /*ARGSUSED*/ 366 1.2.2.2 skrll ptmioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct lwp *l) 367 1.2.2.2 skrll { 368 1.2.2.2 skrll int error; 369 1.2.2.2 skrll dev_t newdev; 370 1.2.2.2 skrll int cfd, sfd; 371 1.2.2.2 skrll struct file *fp; 372 1.2.2.2 skrll struct proc *p = l->l_proc; 373 1.2.2.2 skrll 374 1.2.2.2 skrll error = 0; 375 1.2.2.2 skrll switch (cmd) { 376 1.2.2.2 skrll case TIOCPTMGET: 377 1.2.2.2 skrll if ((error = pty_alloc_master(l, &cfd, &newdev)) != 0) 378 1.2.2.2 skrll return error; 379 1.2.2.2 skrll 380 1.2.2.2 skrll if ((error = pty_grant_slave(l, newdev)) != 0) 381 1.2.2.2 skrll goto bad; 382 1.2.2.2 skrll 383 1.2.2.2 skrll if ((error = pty_alloc_slave(l, &sfd, newdev)) != 0) 384 1.2.2.2 skrll goto bad; 385 1.2.2.2 skrll 386 1.2.2.2 skrll /* now, put the indices and names into struct ptmget */ 387 1.2.2.2 skrll return pty_fill_ptmget(newdev, cfd, sfd, data); 388 1.2.2.2 skrll default: 389 1.2.2.2 skrll DPRINTF(("ptmioctl EINVAL\n")); 390 1.2.2.2 skrll return EINVAL; 391 1.2.2.2 skrll } 392 1.2.2.2 skrll bad: 393 1.2.2.2 skrll fp = fd_getfile(p->p_fd, cfd); 394 1.2.2.2 skrll fdremove(p->p_fd, cfd); 395 1.2.2.2 skrll ffree(fp); 396 1.2.2.2 skrll return error; 397 1.2.2.2 skrll } 398 1.2.2.2 skrll #endif 399
Indexes created Thu Oct 02 14:10:14 GMT 2025