1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 22 /* 23 * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved. 24 */ 25 26 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */ 27 /* All Rights Reserved */ 28 29 /* 30 * Portions of this source code were derived from Berkeley 4.3 BSD 31 * under license from the Regents of the University of California. 32 */ 33 34 #include <sys/param.h> 35 #include <sys/isa_defs.h> 36 #include <sys/types.h> 37 #include <sys/sysmacros.h> 38 #include <sys/user.h> 39 #include <sys/systm.h> 40 #include <sys/errno.h> 41 #include <sys/fcntl.h> 42 #include <sys/stat.h> 43 #include <sys/vnode.h> 44 #include <sys/vfs.h> 45 #include <sys/file.h> 46 #include <sys/mode.h> 47 #include <sys/uio.h> 48 #include <sys/debug.h> 49 #include <c2/audit.h> 50 51 /* 52 * Common code for openat(). Check permissions, allocate an open 53 * file structure, and call the device open routine (if any). 54 */ 55 56 static int 57 copen(int startfd, char *fname, int filemode, int createmode) 58 { 59 struct pathname pn; 60 vnode_t *vp, *sdvp; 61 file_t *fp, *startfp; 62 enum vtype type; 63 int error; 64 int fd, dupfd; 65 vnode_t *startvp; 66 proc_t *p = curproc; 67 uio_seg_t seg = UIO_USERSPACE; 68 char *open_filename = fname; 69 uint32_t auditing = AU_AUDITING(); 70 71 if (startfd == AT_FDCWD) { 72 /* 73 * Regular open() 74 */ 75 startvp = NULL; 76 } else { 77 /* 78 * We're here via openat() 79 */ 80 char startchar; 81 82 if (copyin(fname, &startchar, sizeof (char))) 83 return (set_errno(EFAULT)); 84 85 /* 86 * if startchar is / then startfd is ignored 87 */ 88 if (startchar == '/') 89 startvp = NULL; 90 else { 91 if ((startfp = getf(startfd)) == NULL) 92 return (set_errno(EBADF)); 93 startvp = startfp->f_vnode; 94 VN_HOLD(startvp); 95 releasef(startfd); 96 } 97 } 98 99 /* 100 * Handle openattrdirat request 101 */ 102 if (filemode & FXATTRDIROPEN) { 103 if (auditing) 104 audit_setfsat_path(1); 105 106 if (error = lookupnameat(fname, seg, FOLLOW, 107 NULLVPP, &vp, startvp)) 108 return (set_errno(error)); 109 if (startvp) { 110 VN_RELE(startvp); 111 startvp = NULL; 112 } 113 114 startvp = vp; 115 } 116 117 /* 118 * Do we need to go into extended attribute space? 119 */ 120 if (filemode & (FXATTR|FXATTRDIROPEN)) { 121 vattr_t vattr; 122 123 /* 124 * Make sure we have a valid request. 125 * We must either have a real fd or AT_FDCWD 126 */ 127 128 if (startfd != AT_FDCWD && startvp == NULL) { 129 error = EINVAL; 130 goto out; 131 } 132 133 if (error = pn_get(fname, UIO_USERSPACE, &pn)) { 134 goto out; 135 } 136 137 if (startfd == AT_FDCWD && !(filemode & FXATTRDIROPEN)) { 138 mutex_enter(&p->p_lock); 139 startvp = PTOU(p)->u_cdir; 140 VN_HOLD(startvp); 141 mutex_exit(&p->p_lock); 142 } 143 144 /* 145 * In order to access hidden attribute directory the 146 * user must be able to stat() the file 147 */ 148 149 vattr.va_mask = AT_ALL; 150 if (error = VOP_GETATTR(startvp, &vattr, 0, CRED(), NULL)) { 151 pn_free(&pn); 152 goto out; 153 } 154 155 if ((startvp->v_vfsp->vfs_flag & VFS_XATTR) != 0 || 156 vfs_has_feature(startvp->v_vfsp, VFSFT_SYSATTR_VIEWS)) { 157 error = VOP_LOOKUP(startvp, "", &sdvp, &pn, 158 (filemode & FXATTRDIROPEN) ? LOOKUP_XATTR : 159 LOOKUP_XATTR|CREATE_XATTR_DIR, rootvp, CRED(), 160 NULL, NULL, NULL); 161 } else { 162 error = EINVAL; 163 } 164 165 /* 166 * For openattrdirat use "." as filename to open 167 * as part of vn_openat() 168 */ 169 if (error == 0 && (filemode & FXATTRDIROPEN)) { 170 open_filename = "."; 171 seg = UIO_SYSSPACE; 172 } 173 174 pn_free(&pn); 175 if (error != 0) 176 goto out; 177 178 VN_RELE(startvp); 179 startvp = sdvp; 180 } 181 182 if ((filemode & (FREAD|FWRITE|FXATTRDIROPEN)) != 0) { 183 if ((filemode & (FNONBLOCK|FNDELAY)) == (FNONBLOCK|FNDELAY)) 184 filemode &= ~FNDELAY; 185 error = falloc((vnode_t *)NULL, filemode, &fp, &fd); 186 if (error == 0) { 187 if (auditing) 188 audit_setfsat_path(1); 189 /* 190 * Last arg is a don't-care term if 191 * !(filemode & FCREAT). 192 */ 193 194 error = vn_openat(open_filename, seg, filemode, 195 (int)(createmode & MODEMASK), 196 &vp, CRCREAT, PTOU(curproc)->u_cmask, 197 startvp, fd); 198 199 if (startvp != NULL) 200 VN_RELE(startvp); 201 if (error == 0) { 202 if ((vp->v_flag & VDUP) == 0) { 203 fp->f_vnode = vp; 204 mutex_exit(&fp->f_tlock); 205 /* 206 * We must now fill in the slot 207 * falloc reserved. 208 */ 209 setf(fd, fp); 210 return (fd); 211 } else { 212 /* 213 * Special handling for /dev/fd. 214 * Give up the file pointer 215 * and dup the indicated file descriptor 216 * (in v_rdev). This is ugly, but I've 217 * seen worse. 218 */ 219 unfalloc(fp); 220 dupfd = getminor(vp->v_rdev); 221 type = vp->v_type; 222 mutex_enter(&vp->v_lock); 223 vp->v_flag &= ~VDUP; 224 mutex_exit(&vp->v_lock); 225 VN_RELE(vp); 226 if (type != VCHR) 227 return (set_errno(EINVAL)); 228 if ((fp = getf(dupfd)) == NULL) { 229 setf(fd, NULL); 230 return (set_errno(EBADF)); 231 } 232 mutex_enter(&fp->f_tlock); 233 fp->f_count++; 234 mutex_exit(&fp->f_tlock); 235 setf(fd, fp); 236 releasef(dupfd); 237 } 238 return (fd); 239 } else { 240 setf(fd, NULL); 241 unfalloc(fp); 242 return (set_errno(error)); 243 } 244 } 245 } else { 246 error = EINVAL; 247 } 248 out: 249 if (startvp != NULL) 250 VN_RELE(startvp); 251 return (set_errno(error)); 252 } 253 254 #define OPENMODE32(fmode) ((int)((fmode)-FOPEN)) 255 #define OPENMODE64(fmode) (OPENMODE32(fmode) | FOFFMAX) 256 #define OPENMODEATTRDIR FXATTRDIROPEN 257 #ifdef _LP64 258 #define OPENMODE(fmode) OPENMODE64(fmode) 259 #else 260 #define OPENMODE OPENMODE32 261 #endif 262 263 /* 264 * Open a file. 265 */ 266 int 267 openat(int fd, char *path, int fmode, int cmode) 268 { 269 return (copen(fd, path, OPENMODE(fmode), cmode)); 270 } 271 272 int 273 open(char *path, int fmode, int cmode) 274 { 275 return (openat(AT_FDCWD, path, fmode, cmode)); 276 } 277 278 #if defined(_ILP32) || defined(_SYSCALL32_IMPL) 279 /* 280 * Open for large files in 32-bit environment. Sets the FOFFMAX flag. 281 */ 282 int 283 openat64(int fd, char *path, int fmode, int cmode) 284 { 285 return (copen(fd, path, OPENMODE64(fmode), cmode)); 286 } 287 288 int 289 open64(char *path, int fmode, int cmode) 290 { 291 return (openat64(AT_FDCWD, path, fmode, cmode)); 292 } 293 294 #endif /* _ILP32 || _SYSCALL32_IMPL */ 295 296 #ifdef _SYSCALL32_IMPL 297 /* 298 * Open for 32-bit compatibility on 64-bit kernel 299 */ 300 int 301 openat32(int fd, char *path, int fmode, int cmode) 302 { 303 return (copen(fd, path, OPENMODE32(fmode), cmode)); 304 } 305 306 int 307 open32(char *path, int fmode, int cmode) 308 { 309 return (openat32(AT_FDCWD, path, fmode, cmode)); 310 } 311 312 #endif /* _SYSCALL32_IMPL */ 313