1 /* $NetBSD: vfs_syscalls_12.c,v 1.35 2017/12/03 15:23:30 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * From: @(#)vfs_syscalls.c 8.28 (Berkeley) 12/10/94 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: vfs_syscalls_12.c,v 1.35 2017/12/03 15:23:30 christos Exp $"); 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/namei.h> 45 #include <sys/filedesc.h> 46 #include <sys/kernel.h> 47 #include <sys/file.h> 48 #include <sys/stat.h> 49 #include <sys/socketvar.h> 50 #include <sys/vnode.h> 51 #include <sys/proc.h> 52 #include <sys/uio.h> 53 #include <sys/dirent.h> 54 #include <sys/vfs_syscalls.h> 55 56 #include <sys/syscallargs.h> 57 58 #include <compat/sys/stat.h> 59 #include <compat/sys/dirent.h> 60 61 /* 62 * Convert from a new to an old stat structure. 63 */ 64 void 65 compat_12_stat_conv(const struct stat *st, struct stat12 *ost) 66 { 67 68 ost->st_dev = st->st_dev; 69 ost->st_ino = st->st_ino; 70 ost->st_mode = st->st_mode & 0xffff; 71 if (st->st_nlink >= (1 << 15)) 72 ost->st_nlink = (1 << 15) - 1; 73 else 74 ost->st_nlink = st->st_nlink; 75 ost->st_uid = st->st_uid; 76 ost->st_gid = st->st_gid; 77 ost->st_rdev = st->st_rdev; 78 timespec_to_timespec50(&st->st_atimespec, &ost->st_atimespec); 79 timespec_to_timespec50(&st->st_mtimespec, &ost->st_mtimespec); 80 timespec_to_timespec50(&st->st_ctimespec, &ost->st_ctimespec); 81 ost->st_size = st->st_size; 82 ost->st_blocks = st->st_blocks; 83 ost->st_blksize = st->st_blksize; 84 ost->st_flags = st->st_flags; 85 ost->st_gen = st->st_gen; 86 } 87 88 /* 89 * Read a block of directory entries in a file system independent format. 90 */ 91 int 92 compat_12_sys_getdirentries(struct lwp *l, const struct compat_12_sys_getdirentries_args *uap, register_t *retval) 93 { 94 /* { 95 syscallarg(int) fd; 96 syscallarg(char *) buf; 97 syscallarg(u_int) count; 98 syscallarg(long *) basep; 99 } */ 100 struct dirent *bdp; 101 struct vnode *vp; 102 char *inp, *tbuf; /* Current-format */ 103 int len, reclen; /* Current-format */ 104 char *outp; /* Dirent12-format */ 105 int resid, old_reclen = 0; /* Dirent12-format */ 106 struct file *fp; 107 struct uio auio; 108 struct iovec aiov; 109 struct dirent12 idb; 110 off_t off; /* true file offset */ 111 int buflen, error, eofflag, nbytes; 112 struct vattr va; 113 off_t *cookiebuf = NULL, *cookie; 114 int ncookies; 115 long loff; 116 117 /* fd_getvnode() will use the descriptor for us */ 118 if ((error = fd_getvnode(SCARG(uap, fd), &fp)) != 0) 119 return (error); 120 121 if ((fp->f_flag & FREAD) == 0) { 122 error = EBADF; 123 goto out1; 124 } 125 126 vp = (struct vnode *)fp->f_vnode; 127 if (vp->v_type != VDIR) { 128 error = ENOTDIR; 129 goto out1; 130 } 131 132 vn_lock(vp, LK_SHARED | LK_RETRY); 133 error = VOP_GETATTR(vp, &va, l->l_cred); 134 VOP_UNLOCK(vp); 135 if (error) 136 goto out1; 137 138 loff = fp->f_offset; 139 nbytes = SCARG(uap, count); 140 buflen = min(MAXBSIZE, nbytes); 141 if (buflen < va.va_blocksize) 142 buflen = va.va_blocksize; 143 tbuf = malloc(buflen, M_TEMP, M_WAITOK); 144 145 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 146 off = fp->f_offset; 147 again: 148 aiov.iov_base = tbuf; 149 aiov.iov_len = buflen; 150 auio.uio_iov = &aiov; 151 auio.uio_iovcnt = 1; 152 auio.uio_rw = UIO_READ; 153 auio.uio_resid = buflen; 154 auio.uio_offset = off; 155 UIO_SETUP_SYSSPACE(&auio); 156 /* 157 * First we read into the malloc'ed buffer, then 158 * we massage it into user space, one record at a time. 159 */ 160 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, &cookiebuf, 161 &ncookies); 162 if (error) 163 goto out; 164 165 inp = tbuf; 166 outp = SCARG(uap, buf); 167 resid = nbytes; 168 if ((len = buflen - auio.uio_resid) == 0) 169 goto eof; 170 171 for (cookie = cookiebuf; len > 0; len -= reclen) { 172 bdp = (struct dirent *)inp; 173 reclen = bdp->d_reclen; 174 if (reclen & 3) { 175 error = EIO; 176 goto out; 177 } 178 if (bdp->d_fileno == 0) { 179 inp += reclen; /* it is a hole; squish it out */ 180 if (cookie) 181 off = *cookie++; 182 else 183 off += reclen; 184 continue; 185 } 186 if (bdp->d_namlen >= sizeof(idb.d_name)) 187 idb.d_namlen = sizeof(idb.d_name) - 1; 188 else 189 idb.d_namlen = bdp->d_namlen; 190 old_reclen = _DIRENT_RECLEN(&idb, bdp->d_namlen); 191 if (reclen > len || resid < old_reclen) { 192 /* entry too big for buffer, so just stop */ 193 outp++; 194 break; 195 } 196 /* 197 * Massage in place to make a Dirent12-shaped dirent (otherwise 198 * we have to worry about touching user memory outside of 199 * the copyout() call). 200 */ 201 idb.d_fileno = (uint32_t)bdp->d_fileno; 202 idb.d_reclen = (uint16_t)old_reclen; 203 idb.d_type = (uint8_t)bdp->d_type; 204 (void)memcpy(idb.d_name, bdp->d_name, idb.d_namlen); 205 memset(idb.d_name + idb.d_namlen, 0, 206 idb.d_reclen - _DIRENT_NAMEOFF(&idb) - idb.d_namlen); 207 if ((error = copyout(&idb, outp, old_reclen))) 208 goto out; 209 /* advance past this real entry */ 210 inp += reclen; 211 if (cookie) 212 off = *cookie++; /* each entry points to itself */ 213 else 214 off += reclen; 215 /* advance output past Dirent12-shaped entry */ 216 outp += old_reclen; 217 resid -= old_reclen; 218 } 219 220 /* if we squished out the whole block, try again */ 221 if (outp == SCARG(uap, buf)) { 222 if (cookiebuf) 223 free(cookiebuf, M_TEMP); 224 cookiebuf = NULL; 225 goto again; 226 } 227 fp->f_offset = off; /* update the vnode offset */ 228 229 eof: 230 *retval = nbytes - resid; 231 out: 232 VOP_UNLOCK(vp); 233 if (cookiebuf) 234 free(cookiebuf, M_TEMP); 235 free(tbuf, M_TEMP); 236 out1: 237 fd_putfile(SCARG(uap, fd)); 238 if (error) 239 return error; 240 return copyout(&loff, SCARG(uap, basep), sizeof(long)); 241 } 242 243 /* 244 * Get file status; this version follows links. 245 */ 246 /* ARGSUSED */ 247 int 248 compat_12_sys_stat(struct lwp *l, const struct compat_12_sys_stat_args *uap, register_t *retval) 249 { 250 /* { 251 syscallarg(const char *) path; 252 syscallarg(struct stat12 *) ub; 253 } */ 254 struct stat sb; 255 struct stat12 osb; 256 int error; 257 258 error = do_sys_stat(SCARG(uap, path), FOLLOW, &sb); 259 if (error) 260 return (error); 261 compat_12_stat_conv(&sb, &osb); 262 error = copyout(&osb, SCARG(uap, ub), sizeof (osb)); 263 return (error); 264 } 265 266 267 /* 268 * Get file status; this version does not follow links. 269 */ 270 /* ARGSUSED */ 271 int 272 compat_12_sys_lstat(struct lwp *l, const struct compat_12_sys_lstat_args *uap, register_t *retval) 273 { 274 /* { 275 syscallarg(const char *) path; 276 syscallarg(struct stat12 *) ub; 277 } */ 278 struct stat sb; 279 struct stat12 osb; 280 int error; 281 282 error = do_sys_stat(SCARG(uap, path), NOFOLLOW, &sb); 283 if (error) 284 return (error); 285 compat_12_stat_conv(&sb, &osb); 286 error = copyout(&osb, SCARG(uap, ub), sizeof (osb)); 287 return (error); 288 } 289 290 /* 291 * Return status information about a file descriptor. 292 */ 293 /* ARGSUSED */ 294 int 295 compat_12_sys_fstat(struct lwp *l, const struct compat_12_sys_fstat_args *uap, register_t *retval) 296 { 297 /* { 298 syscallarg(int) fd; 299 syscallarg(struct stat12 *) sb; 300 } */ 301 struct stat ub; 302 struct stat12 oub; 303 int error; 304 305 error = do_sys_fstat(SCARG(uap, fd), &ub); 306 if (error == 0) { 307 compat_12_stat_conv(&ub, &oub); 308 error = copyout(&oub, SCARG(uap, sb), sizeof (oub)); 309 } 310 return (error); 311 } 312