/* $NetBSD: vfs_vnops.c,v 1.62 2003/02/01 07:23:56 atatat Exp $ */ /* * Copyright (c) 1982, 1986, 1989, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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. * * @(#)vfs_vnops.c 8.14 (Berkeley) 6/15/95 */ #include __KERNEL_RCSID(0, "$NetBSD: vfs_vnops.c,v 1.62 2003/02/01 07:23:56 atatat Exp $"); #include "fs_union.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef UNION #include #endif #include extern LIST_HEAD(veriexec_devhead, veriexec_dev_list) veriexec_dev_head; extern struct veriexec_devhead veriexec_file_dev_head; static int vn_read(struct file *fp, off_t *offset, struct uio *uio, struct ucred *cred, int flags); static int vn_write(struct file *fp, off_t *offset, struct uio *uio, struct ucred *cred, int flags); static int vn_closefile(struct file *fp, struct proc *p); static int vn_poll(struct file *fp, int events, struct proc *p); static int vn_fcntl(struct file *fp, u_int com, caddr_t data, struct proc *p); static int vn_statfile(struct file *fp, struct stat *sb, struct proc *p); static int vn_ioctl(struct file *fp, u_long com, caddr_t data, struct proc *p); struct fileops vnops = { vn_read, vn_write, vn_ioctl, vn_fcntl, vn_poll, vn_statfile, vn_closefile, vn_kqfilter }; /* * Common code for vnode open operations. * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. */ int vn_open(ndp, fmode, cmode) struct nameidata *ndp; int fmode, cmode; { struct vnode *vp; struct proc *p = ndp->ni_cnd.cn_proc; struct ucred *cred = p->p_ucred; struct vattr va; int error; #ifdef VERIFIED_EXEC char got_dev; struct veriexec_inode_list *veriexec_node; char fingerprint[MAXFINGERPRINTLEN]; #endif if (fmode & O_CREAT) { ndp->ni_cnd.cn_nameiop = CREATE; ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF; if ((fmode & O_EXCL) == 0 && ((fmode & O_NOFOLLOW) == 0)) ndp->ni_cnd.cn_flags |= FOLLOW; if ((error = namei(ndp)) != 0) return (error); if (ndp->ni_vp == NULL) { VATTR_NULL(&va); va.va_type = VREG; va.va_mode = cmode; if (fmode & O_EXCL) va.va_vaflags |= VA_EXCLUSIVE; VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE); error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, &ndp->ni_cnd, &va); if (error) return (error); fmode &= ~O_TRUNC; vp = ndp->ni_vp; } else { VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); if (ndp->ni_dvp == ndp->ni_vp) vrele(ndp->ni_dvp); else vput(ndp->ni_dvp); ndp->ni_dvp = NULL; vp = ndp->ni_vp; if (fmode & O_EXCL) { error = EEXIST; goto bad; } if (ndp->ni_vp->v_type == VLNK) { error = EFTYPE; goto bad; } fmode &= ~O_CREAT; } } else { ndp->ni_cnd.cn_nameiop = LOOKUP; ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF; if ((error = namei(ndp)) != 0) return (error); vp = ndp->ni_vp; } if (vp->v_type == VSOCK) { error = EOPNOTSUPP; goto bad; } #ifdef VERIFIED_EXEC veriexec_node = NULL; if ((error = VOP_GETATTR(vp, &va, cred, p)) != 0) goto bad; #endif if ((fmode & O_CREAT) == 0) { #ifdef VERIFIED_EXEC /* * Look for the file on the fingerprint lists iff * it has not been seen before. */ if ((vp->fp_status == FINGERPRINT_INVALID) || (vp->fp_status == FINGERPRINT_NODEV)) { /* check the file list for the finger print */ veriexec_node = get_veriexec_inode(&veriexec_file_dev_head, va.va_fsid, va.va_fileid, &got_dev); if (veriexec_node == NULL) { /* failing that, check the exec list */ veriexec_node = get_veriexec_inode( &veriexec_dev_head, va.va_fsid, va.va_fileid, &got_dev); } if ((veriexec_node == NULL) && (got_dev == 1)) vp->fp_status = FINGERPRINT_NOENTRY; if (veriexec_node != NULL) { if ((error = evaluate_fingerprint(vp, veriexec_node, p, va.va_size, fingerprint)) != 0) goto bad; if (fingerprintcmp(veriexec_node, fingerprint) == 0) { /* fingerprint ok */ vp->fp_status = FINGERPRINT_VALID; #ifdef VERIFIED_EXEC_DEBUG printf( "file fingerprint matches for dev %lu, file %lu\n", va.va_fsid, va.va_fileid); #endif } else { vp->fp_status = FINGERPRINT_NOMATCH; } } } #endif if (fmode & FREAD) { if ((error = VOP_ACCESS(vp, VREAD, cred, p)) != 0) goto bad; #ifdef VERIFIED_EXEC /* file is on finger print list */ if (vp->fp_status == FINGERPRINT_NOMATCH) { /* fingerprint bad */ printf( "file fingerprint does not match on dev %lu, file %lu\n", va.va_fsid, va.va_fileid); if (securelevel > 2) { error = EPERM; goto bad; } } #endif } if (fmode & (FWRITE | O_TRUNC)) { if (vp->v_type == VDIR) { error = EISDIR; goto bad; } if ((error = vn_writechk(vp)) != 0 || (error = VOP_ACCESS(vp, VWRITE, cred, p)) != 0) goto bad; #ifdef VERIFIED_EXEC /* * If file has a fingerprint then * deny the write request, otherwise * invalidate the status so we don't * keep checking for the file having * a fingerprint. */ if (vp->fp_status == FINGERPRINT_VALID) { printf( "writing to fingerprinted file for dev %lu, file %lu\n", va.va_fsid, va.va_fileid); if (securelevel > 2) { error = EPERM; goto bad; } else { vp->fp_status = FINGERPRINT_INVALID; } } #endif } } if (fmode & O_TRUNC) { VOP_UNLOCK(vp, 0); /* XXX */ VOP_LEASE(vp, p, cred, LEASE_WRITE); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */ VATTR_NULL(&va); va.va_size = 0; if ((error = VOP_SETATTR(vp, &va, cred, p)) != 0) goto bad; } if ((error = VOP_OPEN(vp, fmode, cred, p)) != 0) goto bad; if (vp->v_type == VREG && uvn_attach(vp, fmode & FWRITE ? VM_PROT_WRITE : 0) == NULL) { error = EIO; goto bad; } if (fmode & FWRITE) vp->v_writecount++; return (0); bad: vput(vp); return (error); } /* * Check for write permissions on the specified vnode. * Prototype text segments cannot be written. */ int vn_writechk(vp) struct vnode *vp; { /* * If the vnode is in use as a process's text, * we can't allow writing. */ if (vp->v_flag & VTEXT) return (ETXTBSY); return (0); } /* * Mark a vnode as having executable mappings. */ void vn_markexec(vp) struct vnode *vp; { if ((vp->v_flag & VEXECMAP) == 0) { uvmexp.filepages -= vp->v_uobj.uo_npages; uvmexp.execpages += vp->v_uobj.uo_npages; } vp->v_flag |= VEXECMAP; } /* * Mark a vnode as being the text of a process. * Fail if the vnode is currently writable. */ int vn_marktext(vp) struct vnode *vp; { if (vp->v_writecount != 0) { KASSERT((vp->v_flag & VTEXT) == 0); return (ETXTBSY); } vp->v_flag |= VTEXT; vn_markexec(vp); return (0); } /* * Vnode close call * * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node. */ int vn_close(vp, flags, cred, p) struct vnode *vp; int flags; struct ucred *cred; struct proc *p; { int error; if (flags & FWRITE) vp->v_writecount--; vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); error = VOP_CLOSE(vp, flags, cred, p); vput(vp); return (error); } /* * Package up an I/O request on a vnode into a uio and do it. */ int vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p) enum uio_rw rw; struct vnode *vp; caddr_t base; int len; off_t offset; enum uio_seg segflg; int ioflg; struct ucred *cred; size_t *aresid; struct proc *p; { struct uio auio; struct iovec aiov; int error; if ((ioflg & IO_NODELOCKED) == 0) { if (rw == UIO_READ) { vn_lock(vp, LK_SHARED | LK_RETRY); } else { vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); } } auio.uio_iov = &aiov; auio.uio_iovcnt = 1; aiov.iov_base = base; aiov.iov_len = len; auio.uio_resid = len; auio.uio_offset = offset; auio.uio_segflg = segflg; auio.uio_rw = rw; auio.uio_procp = p; if (rw == UIO_READ) { error = VOP_READ(vp, &auio, ioflg, cred); } else { error = VOP_WRITE(vp, &auio, ioflg, cred); } if (aresid) *aresid = auio.uio_resid; else if (auio.uio_resid && error == 0) error = EIO; if ((ioflg & IO_NODELOCKED) == 0) VOP_UNLOCK(vp, 0); return (error); } int vn_readdir(fp, buf, segflg, count, done, p, cookies, ncookies) struct file *fp; char *buf; int segflg, *done, *ncookies; u_int count; struct proc *p; off_t **cookies; { struct vnode *vp = (struct vnode *)fp->f_data; struct iovec aiov; struct uio auio; int error, eofflag; unionread: if (vp->v_type != VDIR) return (EINVAL); aiov.iov_base = buf; aiov.iov_len = count; auio.uio_iov = &aiov; auio.uio_iovcnt = 1; auio.uio_rw = UIO_READ; auio.uio_segflg = segflg; auio.uio_procp = p; auio.uio_resid = count; vn_lock(vp, LK_SHARED | LK_RETRY); auio.uio_offset = fp->f_offset; error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies, ncookies); fp->f_offset = auio.uio_offset; VOP_UNLOCK(vp, 0); if (error) return (error); #ifdef UNION { extern struct vnode *union_dircache __P((struct vnode *)); if (count == auio.uio_resid && (vp->v_op == union_vnodeop_p)) { struct vnode *lvp; lvp = union_dircache(vp); if (lvp != NULLVP) { struct vattr va; /* * If the directory is opaque, * then don't show lower entries */ error = VOP_GETATTR(vp, &va, fp->f_cred, p); if (va.va_flags & OPAQUE) { vput(lvp); lvp = NULL; } } if (lvp != NULLVP) { error = VOP_OPEN(lvp, FREAD, fp->f_cred, p); if (error) { vput(lvp); return (error); } VOP_UNLOCK(lvp, 0); fp->f_data = (caddr_t) lvp; fp->f_offset = 0; error = vn_close(vp, FREAD, fp->f_cred, p); if (error) return (error); vp = lvp; goto unionread; } } } #endif /* UNION */ if (count == auio.uio_resid && (vp->v_flag & VROOT) && (vp->v_mount->mnt_flag & MNT_UNION)) { struct vnode *tvp = vp; vp = vp->v_mount->mnt_vnodecovered; VREF(vp); fp->f_data = (caddr_t) vp; fp->f_offset = 0; vrele(tvp); goto unionread; } *done = count - auio.uio_resid; return error; } /* * File table vnode read routine. */ static int vn_read(fp, offset, uio, cred, flags) struct file *fp; off_t *offset; struct uio *uio; struct ucred *cred; int flags; { struct vnode *vp = (struct vnode *)fp->f_data; int count, error, ioflag = 0; VOP_LEASE(vp, uio->uio_procp, cred, LEASE_READ); if (fp->f_flag & FNONBLOCK) ioflag |= IO_NDELAY; if ((fp->f_flag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC)) ioflag |= IO_SYNC; if (fp->f_flag & FALTIO) ioflag |= IO_ALTSEMANTICS; vn_lock(vp, LK_SHARED | LK_RETRY); uio->uio_offset = *offset; count = uio->uio_resid; error = VOP_READ(vp, uio, ioflag, cred); if (flags & FOF_UPDATE_OFFSET) *offset += count - uio->uio_resid; VOP_UNLOCK(vp, 0); return (error); } /* * File table vnode write routine. */ static int vn_write(fp, offset, uio, cred, flags) struct file *fp; off_t *offset; struct uio *uio; struct ucred *cred; int flags; { struct vnode *vp = (struct vnode *)fp->f_data; int count, error, ioflag = IO_UNIT; if (vp->v_type == VREG && (fp->f_flag & O_APPEND)) ioflag |= IO_APPEND; if (fp->f_flag & FNONBLOCK) ioflag |= IO_NDELAY; if (fp->f_flag & FFSYNC || (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))) ioflag |= IO_SYNC; else if (fp->f_flag & FDSYNC) ioflag |= IO_DSYNC; if (fp->f_flag & FALTIO) ioflag |= IO_ALTSEMANTICS; VOP_LEASE(vp, uio->uio_procp, cred, LEASE_WRITE); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); uio->uio_offset = *offset; count = uio->uio_resid; error = VOP_WRITE(vp, uio, ioflag, cred); if (flags & FOF_UPDATE_OFFSET) { if (ioflag & IO_APPEND) *offset = uio->uio_offset; else *offset += count - uio->uio_resid; } VOP_UNLOCK(vp, 0); return (error); } /* * File table vnode stat routine. */ static int vn_statfile(fp, sb, p) struct file *fp; struct stat *sb; struct proc *p; { struct vnode *vp = (struct vnode *)fp->f_data; return vn_stat(vp, sb, p); } int vn_stat(vp, sb, p) struct vnode *vp; struct stat *sb; struct proc *p; { struct vattr va; int error; mode_t mode; error = VOP_GETATTR(vp, &va, p->p_ucred, p); if (error) return (error); /* * Copy from vattr table */ sb->st_dev = va.va_fsid; sb->st_ino = va.va_fileid; mode = va.va_mode; switch (vp->v_type) { case VREG: mode |= S_IFREG; break; case VDIR: mode |= S_IFDIR; break; case VBLK: mode |= S_IFBLK; break; case VCHR: mode |= S_IFCHR; break; case VLNK: mode |= S_IFLNK; break; case VSOCK: mode |= S_IFSOCK; break; case VFIFO: mode |= S_IFIFO; break; default: return (EBADF); }; sb->st_mode = mode; sb->st_nlink = va.va_nlink; sb->st_uid = va.va_uid; sb->st_gid = va.va_gid; sb->st_rdev = va.va_rdev; sb->st_size = va.va_size; sb->st_atimespec = va.va_atime; sb->st_mtimespec = va.va_mtime; sb->st_ctimespec = va.va_ctime; sb->st_blksize = va.va_blocksize; sb->st_flags = va.va_flags; sb->st_gen = 0; sb->st_blocks = va.va_bytes / S_BLKSIZE; return (0); } /* * File table vnode fcntl routine. */ static int vn_fcntl(fp, com, data, p) struct file *fp; u_int com; caddr_t data; struct proc *p; { struct vnode *vp = ((struct vnode *)fp->f_data); int error; vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); error = VOP_FCNTL(vp, com, data, fp->f_flag, p->p_ucred, p); VOP_UNLOCK(vp, 0); return (error); } /* * File table vnode ioctl routine. */ static int vn_ioctl(fp, com, data, p) struct file *fp; u_long com; caddr_t data; struct proc *p; { struct vnode *vp = ((struct vnode *)fp->f_data); struct vattr vattr; int error; switch (vp->v_type) { case VREG: case VDIR: if (com == FIONREAD) { error = VOP_GETATTR(vp, &vattr, p->p_ucred, p); if (error) return (error); *(int *)data = vattr.va_size - fp->f_offset; return (0); } if (com == FIOGETBMAP) { daddr_t *block; if (*(daddr_t *)data < 0) return (EINVAL); block = (daddr_t *)data; return (VOP_BMAP(vp, *block, NULL, block, NULL)); } if (com == OFIOGETBMAP) { daddr_t ibn, obn; if (*(int32_t *)data < 0) return (EINVAL); ibn = (daddr_t)*(int32_t *)data; error = VOP_BMAP(vp, ibn, NULL, &obn, NULL); *(int32_t *)data = (int32_t)obn; return error; } if (com == FIONBIO || com == FIOASYNC) /* XXX */ return (0); /* XXX */ /* fall into ... */ default: return (EPASSTHROUGH); case VFIFO: case VCHR: case VBLK: error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p); if (error == 0 && com == TIOCSCTTY) { if (p->p_session->s_ttyvp) vrele(p->p_session->s_ttyvp); p->p_session->s_ttyvp = vp; VREF(vp); } return (error); } } /* * File table vnode poll routine. */ static int vn_poll(fp, events, p) struct file *fp; int events; struct proc *p; { return (VOP_POLL(((struct vnode *)fp->f_data), events, p)); } /* * File table vnode kqfilter routine. */ int vn_kqfilter(fp, kn) struct file *fp; struct knote *kn; { return (VOP_KQFILTER((struct vnode *)fp->f_data, kn)); } /* * Check that the vnode is still valid, and if so * acquire requested lock. */ int vn_lock(vp, flags) struct vnode *vp; int flags; { int error; do { if ((flags & LK_INTERLOCK) == 0) simple_lock(&vp->v_interlock); if (vp->v_flag & VXLOCK) { if (flags & LK_NOWAIT) { simple_unlock(&vp->v_interlock); return EBUSY; } vp->v_flag |= VXWANT; ltsleep(vp, PINOD | PNORELOCK, "vn_lock", 0, &vp->v_interlock); error = ENOENT; } else { error = VOP_LOCK(vp, flags | LK_INTERLOCK); if (error == 0 || error == EDEADLK || error == EBUSY) return (error); } flags &= ~LK_INTERLOCK; } while (flags & LK_RETRY); return (error); } /* * File table vnode close routine. */ static int vn_closefile(fp, p) struct file *fp; struct proc *p; { return (vn_close(((struct vnode *)fp->f_data), fp->f_flag, fp->f_cred, p)); } /* * Enable LK_CANRECURSE on lock. Return prior status. */ u_int vn_setrecurse(vp) struct vnode *vp; { struct lock *lkp = &vp->v_lock; u_int retval = lkp->lk_flags & LK_CANRECURSE; lkp->lk_flags |= LK_CANRECURSE; return retval; } /* * Called when done with locksetrecurse. */ void vn_restorerecurse(vp, flags) struct vnode *vp; u_int flags; { struct lock *lkp = &vp->v_lock; lkp->lk_flags &= ~LK_CANRECURSE; lkp->lk_flags |= flags; }