diff options
Diffstat (limited to 'sys/kern/kern_descrip.c')
| -rw-r--r-- | sys/kern/kern_descrip.c | 3865 |
1 files changed, 3865 insertions, 0 deletions
diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c new file mode 100644 index 0000000..1eb18f1 --- /dev/null +++ b/sys/kern/kern_descrip.c @@ -0,0 +1,3865 @@ +/*- + * Copyright (c) 1982, 1986, 1989, 1991, 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. + * 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. + * + * @(#)kern_descrip.c 8.6 (Berkeley) 4/19/94 + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include "opt_capsicum.h" +#include "opt_compat.h" +#include "opt_ddb.h" +#include "opt_ktrace.h" +#include "opt_procdesc.h" + +#include <sys/param.h> +#include <sys/systm.h> + +#include <sys/capability.h> +#include <sys/conf.h> +#include <sys/domain.h> +#include <sys/fcntl.h> +#include <sys/file.h> +#include <sys/filedesc.h> +#include <sys/filio.h> +#include <sys/jail.h> +#include <sys/kernel.h> +#include <sys/limits.h> +#include <sys/lock.h> +#include <sys/malloc.h> +#include <sys/mman.h> +#include <sys/mount.h> +#include <sys/mqueue.h> +#include <sys/mutex.h> +#include <sys/namei.h> +#include <sys/selinfo.h> +#include <sys/pipe.h> +#include <sys/priv.h> +#include <sys/proc.h> +#include <sys/procdesc.h> +#include <sys/protosw.h> +#include <sys/racct.h> +#include <sys/resourcevar.h> +#include <sys/signalvar.h> +#include <sys/socketvar.h> +#include <sys/stat.h> +#include <sys/sx.h> +#include <sys/syscallsubr.h> +#include <sys/sysctl.h> +#include <sys/sysproto.h> +#include <sys/tty.h> +#include <sys/unistd.h> +#include <sys/un.h> +#include <sys/unpcb.h> +#include <sys/user.h> +#include <sys/vnode.h> +#ifdef KTRACE +#include <sys/ktrace.h> +#endif + +#include <net/vnet.h> + +#include <netinet/in.h> +#include <netinet/in_pcb.h> + +#include <security/audit/audit.h> + +#include <vm/uma.h> +#include <vm/vm.h> + +#include <ddb/ddb.h> + +static MALLOC_DEFINE(M_FILEDESC, "filedesc", "Open file descriptor table"); +static MALLOC_DEFINE(M_FILEDESC_TO_LEADER, "filedesc_to_leader", + "file desc to leader structures"); +static MALLOC_DEFINE(M_SIGIO, "sigio", "sigio structures"); + +MALLOC_DECLARE(M_FADVISE); + +static uma_zone_t file_zone; + + +/* Flags for do_dup() */ +#define DUP_FIXED 0x1 /* Force fixed allocation */ +#define DUP_FCNTL 0x2 /* fcntl()-style errors */ +#define DUP_CLOEXEC 0x4 /* Atomically set FD_CLOEXEC. */ + +static int closefp(struct filedesc *fdp, int fd, struct file *fp, + struct thread *td, int holdleaders); +static int do_dup(struct thread *td, int flags, int old, int new, + register_t *retval); +static int fd_first_free(struct filedesc *fdp, int low, int size); +static int fd_last_used(struct filedesc *fdp, int size); +static void fdgrowtable(struct filedesc *fdp, int nfd); +static void fdunused(struct filedesc *fdp, int fd); +static void fdused(struct filedesc *fdp, int fd); +static int fill_pipe_info(struct pipe *pi, struct kinfo_file *kif); +static int fill_procdesc_info(struct procdesc *pdp, + struct kinfo_file *kif); +static int fill_pts_info(struct tty *tp, struct kinfo_file *kif); +static int fill_shm_info(struct file *fp, struct kinfo_file *kif); +static int fill_socket_info(struct socket *so, struct kinfo_file *kif); +static int fill_vnode_info(struct vnode *vp, struct kinfo_file *kif); + +/* + * A process is initially started out with NDFILE descriptors stored within + * this structure, selected to be enough for typical applications based on + * the historical limit of 20 open files (and the usage of descriptors by + * shells). If these descriptors are exhausted, a larger descriptor table + * may be allocated, up to a process' resource limit; the internal arrays + * are then unused. + */ +#define NDFILE 20 +#define NDSLOTSIZE sizeof(NDSLOTTYPE) +#define NDENTRIES (NDSLOTSIZE * __CHAR_BIT) +#define NDSLOT(x) ((x) / NDENTRIES) +#define NDBIT(x) ((NDSLOTTYPE)1 << ((x) % NDENTRIES)) +#define NDSLOTS(x) (((x) + NDENTRIES - 1) / NDENTRIES) + +/* + * Storage required per open file descriptor. + */ +#define OFILESIZE (sizeof(struct file *) + sizeof(char)) + +/* + * Storage to hold unused ofiles that need to be reclaimed. + */ +struct freetable { + struct file **ft_table; + SLIST_ENTRY(freetable) ft_next; +}; + +/* + * Basic allocation of descriptors: + * one of the above, plus arrays for NDFILE descriptors. + */ +struct filedesc0 { + struct filedesc fd_fd; + /* + * ofiles which need to be reclaimed on free. + */ + SLIST_HEAD(,freetable) fd_free; + /* + * These arrays are used when the number of open files is + * <= NDFILE, and are then pointed to by the pointers above. + */ + struct file *fd_dfiles[NDFILE]; + char fd_dfileflags[NDFILE]; + NDSLOTTYPE fd_dmap[NDSLOTS(NDFILE)]; +}; + +/* + * Descriptor management. + */ +volatile int openfiles; /* actual number of open files */ +struct mtx sigio_lock; /* mtx to protect pointers to sigio */ +void (*mq_fdclose)(struct thread *td, int fd, struct file *fp); + +/* A mutex to protect the association between a proc and filedesc. */ +static struct mtx fdesc_mtx; + +/* + * If low >= size, just return low. Otherwise find the first zero bit in the + * given bitmap, starting at low and not exceeding size - 1. Return size if + * not found. + */ +static int +fd_first_free(struct filedesc *fdp, int low, int size) +{ + NDSLOTTYPE *map = fdp->fd_map; + NDSLOTTYPE mask; + int off, maxoff; + + if (low >= size) + return (low); + + off = NDSLOT(low); + if (low % NDENTRIES) { + mask = ~(~(NDSLOTTYPE)0 >> (NDENTRIES - (low % NDENTRIES))); + if ((mask &= ~map[off]) != 0UL) + return (off * NDENTRIES + ffsl(mask) - 1); + ++off; + } + for (maxoff = NDSLOTS(size); off < maxoff; ++off) + if (map[off] != ~0UL) + return (off * NDENTRIES + ffsl(~map[off]) - 1); + return (size); +} + +/* + * Find the highest non-zero bit in the given bitmap, starting at 0 and + * not exceeding size - 1. Return -1 if not found. + */ +static int +fd_last_used(struct filedesc *fdp, int size) +{ + NDSLOTTYPE *map = fdp->fd_map; + NDSLOTTYPE mask; + int off, minoff; + + off = NDSLOT(size); + if (size % NDENTRIES) { + mask = ~(~(NDSLOTTYPE)0 << (size % NDENTRIES)); + if ((mask &= map[off]) != 0) + return (off * NDENTRIES + flsl(mask) - 1); + --off; + } + for (minoff = NDSLOT(0); off >= minoff; --off) + if (map[off] != 0) + return (off * NDENTRIES + flsl(map[off]) - 1); + return (-1); +} + +static int +fdisused(struct filedesc *fdp, int fd) +{ + + FILEDESC_LOCK_ASSERT(fdp); + + KASSERT(fd >= 0 && fd < fdp->fd_nfiles, + ("file descriptor %d out of range (0, %d)", fd, fdp->fd_nfiles)); + + return ((fdp->fd_map[NDSLOT(fd)] & NDBIT(fd)) != 0); +} + +/* + * Mark a file descriptor as used. + */ +static void +fdused(struct filedesc *fdp, int fd) +{ + + FILEDESC_XLOCK_ASSERT(fdp); + + KASSERT(!fdisused(fdp, fd), ("fd=%d is already used", fd)); + + fdp->fd_map[NDSLOT(fd)] |= NDBIT(fd); + if (fd > fdp->fd_lastfile) + fdp->fd_lastfile = fd; + if (fd == fdp->fd_freefile) + fdp->fd_freefile = fd_first_free(fdp, fd, fdp->fd_nfiles); +} + +/* + * Mark a file descriptor as unused. + */ +static void +fdunused(struct filedesc *fdp, int fd) +{ + + FILEDESC_XLOCK_ASSERT(fdp); + + KASSERT(fdisused(fdp, fd), ("fd=%d is already unused", fd)); + KASSERT(fdp->fd_ofiles[fd] == NULL, ("fd=%d is still in use", fd)); + + fdp->fd_map[NDSLOT(fd)] &= ~NDBIT(fd); + if (fd < fdp->fd_freefile) + fdp->fd_freefile = fd; + if (fd == fdp->fd_lastfile) + fdp->fd_lastfile = fd_last_used(fdp, fd); +} + +/* + * System calls on descriptors. + */ +#ifndef _SYS_SYSPROTO_H_ +struct getdtablesize_args { + int dummy; +}; +#endif +/* ARGSUSED */ +int +sys_getdtablesize(struct thread *td, struct getdtablesize_args *uap) +{ + struct proc *p = td->td_proc; + uint64_t lim; + + PROC_LOCK(p); + td->td_retval[0] = + min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); + lim = racct_get_limit(td->td_proc, RACCT_NOFILE); + PROC_UNLOCK(p); + if (lim < td->td_retval[0]) + td->td_retval[0] = lim; + return (0); +} + +/* + * Duplicate a file descriptor to a particular value. + * + * Note: keep in mind that a potential race condition exists when closing + * descriptors from a shared descriptor table (via rfork). + */ +#ifndef _SYS_SYSPROTO_H_ +struct dup2_args { + u_int from; + u_int to; +}; +#endif +/* ARGSUSED */ +int +sys_dup2(struct thread *td, struct dup2_args *uap) +{ + + return (do_dup(td, DUP_FIXED, (int)uap->from, (int)uap->to, + td->td_retval)); +} + +/* + * Duplicate a file descriptor. + */ +#ifndef _SYS_SYSPROTO_H_ +struct dup_args { + u_int fd; +}; +#endif +/* ARGSUSED */ +int +sys_dup(struct thread *td, struct dup_args *uap) +{ + + return (do_dup(td, 0, (int)uap->fd, 0, td->td_retval)); +} + +/* + * The file control system call. + */ +#ifndef _SYS_SYSPROTO_H_ +struct fcntl_args { + int fd; + int cmd; + long arg; +}; +#endif +/* ARGSUSED */ +int +sys_fcntl(struct thread *td, struct fcntl_args *uap) +{ + struct flock fl; + struct __oflock ofl; + intptr_t arg; + int error; + int cmd; + + error = 0; + cmd = uap->cmd; + switch (uap->cmd) { + case F_OGETLK: + case F_OSETLK: + case F_OSETLKW: + /* + * Convert old flock structure to new. + */ + error = copyin((void *)(intptr_t)uap->arg, &ofl, sizeof(ofl)); + fl.l_start = ofl.l_start; + fl.l_len = ofl.l_len; + fl.l_pid = ofl.l_pid; + fl.l_type = ofl.l_type; + fl.l_whence = ofl.l_whence; + fl.l_sysid = 0; + + switch (uap->cmd) { + case F_OGETLK: + cmd = F_GETLK; + break; + case F_OSETLK: + cmd = F_SETLK; + break; + case F_OSETLKW: + cmd = F_SETLKW; + break; + } + arg = (intptr_t)&fl; + break; + case F_GETLK: + case F_SETLK: + case F_SETLKW: + case F_SETLK_REMOTE: + error = copyin((void *)(intptr_t)uap->arg, &fl, sizeof(fl)); + arg = (intptr_t)&fl; + break; + default: + arg = uap->arg; + break; + } + if (error) + return (error); + error = kern_fcntl(td, uap->fd, cmd, arg); + if (error) + return (error); + if (uap->cmd == F_OGETLK) { + ofl.l_start = fl.l_start; + ofl.l_len = fl.l_len; + ofl.l_pid = fl.l_pid; + ofl.l_type = fl.l_type; + ofl.l_whence = fl.l_whence; + error = copyout(&ofl, (void *)(intptr_t)uap->arg, sizeof(ofl)); + } else if (uap->cmd == F_GETLK) { + error = copyout(&fl, (void *)(intptr_t)uap->arg, sizeof(fl)); + } + return (error); +} + +static inline int +fdunwrap(int fd, cap_rights_t rights, struct filedesc *fdp, struct file **fpp) +{ + + FILEDESC_LOCK_ASSERT(fdp); + + *fpp = fget_locked(fdp, fd); + if (*fpp == NULL) + return (EBADF); + +#ifdef CAPABILITIES + if ((*fpp)->f_type == DTYPE_CAPABILITY) { + int err = cap_funwrap(*fpp, rights, fpp); + if (err != 0) { + *fpp = NULL; + return (err); + } + } +#endif /* CAPABILITIES */ + return (0); +} + +int +kern_fcntl(struct thread *td, int fd, int cmd, intptr_t arg) +{ + struct filedesc *fdp; + struct flock *flp; + struct file *fp; + struct proc *p; + char *pop; + struct vnode *vp; + int error, flg, tmp; + u_int old, new; + uint64_t bsize; + off_t foffset; + + error = 0; + flg = F_POSIX; + p = td->td_proc; + fdp = p->p_fd; + + switch (cmd) { + case F_DUPFD: + tmp = arg; + error = do_dup(td, DUP_FCNTL, fd, tmp, td->td_retval); + break; + + case F_DUPFD_CLOEXEC: + tmp = arg; + error = do_dup(td, DUP_FCNTL | DUP_CLOEXEC, fd, tmp, + td->td_retval); + break; + + case F_DUP2FD: + tmp = arg; + error = do_dup(td, DUP_FIXED, fd, tmp, td->td_retval); + break; + + case F_DUP2FD_CLOEXEC: + tmp = arg; + error = do_dup(td, DUP_FIXED | DUP_CLOEXEC, fd, tmp, + td->td_retval); + break; + + case F_GETFD: + FILEDESC_SLOCK(fdp); + if ((fp = fget_locked(fdp, fd)) == NULL) { + FILEDESC_SUNLOCK(fdp); + error = EBADF; + break; + } + pop = &fdp->fd_ofileflags[fd]; + td->td_retval[0] = (*pop & UF_EXCLOSE) ? FD_CLOEXEC : 0; + FILEDESC_SUNLOCK(fdp); + break; + + case F_SETFD: + FILEDESC_XLOCK(fdp); + if ((fp = fget_locked(fdp, fd)) == NULL) { + FILEDESC_XUNLOCK(fdp); + error = EBADF; + break; + } + pop = &fdp->fd_ofileflags[fd]; + *pop = (*pop &~ UF_EXCLOSE) | + (arg & FD_CLOEXEC ? UF_EXCLOSE : 0); + FILEDESC_XUNLOCK(fdp); + break; + + case F_GETFL: + FILEDESC_SLOCK(fdp); + error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); + if (error != 0) { + FILEDESC_SUNLOCK(fdp); + break; + } + td->td_retval[0] = OFLAGS(fp->f_flag); + FILEDESC_SUNLOCK(fdp); + break; + + case F_SETFL: + FILEDESC_SLOCK(fdp); + error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); + if (error != 0) { + FILEDESC_SUNLOCK(fdp); + break; + } + fhold(fp); + FILEDESC_SUNLOCK(fdp); + do { + tmp = flg = fp->f_flag; + tmp &= ~FCNTLFLAGS; + tmp |= FFLAGS(arg & ~O_ACCMODE) & FCNTLFLAGS; + } while(atomic_cmpset_int(&fp->f_flag, flg, tmp) == 0); + tmp = fp->f_flag & FNONBLOCK; + error = fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); + if (error) { + fdrop(fp, td); + break; + } + tmp = fp->f_flag & FASYNC; + error = fo_ioctl(fp, FIOASYNC, &tmp, td->td_ucred, td); + if (error == 0) { + fdrop(fp, td); + break; + } + atomic_clear_int(&fp->f_flag, FNONBLOCK); + tmp = 0; + (void)fo_ioctl(fp, FIONBIO, &tmp, td->td_ucred, td); + fdrop(fp, td); + break; + + case F_GETOWN: + FILEDESC_SLOCK(fdp); + error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); + if (error != 0) { + FILEDESC_SUNLOCK(fdp); + break; + } + fhold(fp); + FILEDESC_SUNLOCK(fdp); + error = fo_ioctl(fp, FIOGETOWN, &tmp, td->td_ucred, td); + if (error == 0) + td->td_retval[0] = tmp; + fdrop(fp, td); + break; + + case F_SETOWN: + FILEDESC_SLOCK(fdp); + error = fdunwrap(fd, CAP_FCNTL, fdp, &fp); + if (error != 0) { + FILEDESC_SUNLOCK(fdp); + break; + } + fhold(fp); + FILEDESC_SUNLOCK(fdp); + tmp = arg; + error = fo_ioctl(fp, FIOSETOWN, &tmp, td->td_ucred, td); + fdrop(fp, td); + break; + + case F_SETLK_REMOTE: + error = priv_check(td, PRIV_NFS_LOCKD); + if (error) + return (error); + flg = F_REMOTE; + goto do_setlk; + + case F_SETLKW: + flg |= F_WAIT; + /* FALLTHROUGH F_SETLK */ + + case F_SETLK: + do_setlk: + FILEDESC_SLOCK(fdp); + error = fdunwrap(fd, CAP_FLOCK, fdp, &fp); + if (error != 0) { + FILEDESC_SUNLOCK(fdp); + break; + } + if (fp->f_type != DTYPE_VNODE) { + FILEDESC_SUNLOCK(fdp); + error = EBADF; + break; + } + flp = (struct flock *)arg; + if (flp->l_whence == SEEK_CUR) { + foffset = foffset_get(fp); + if (foffset < 0 || + (flp->l_start > 0 && + foffset > OFF_MAX - flp->l_start)) { + FILEDESC_SUNLOCK(fdp); + error = EOVERFLOW; + break; + } + flp->l_start += foffset; + } + + /* + * VOP_ADVLOCK() may block. + */ + fhold(fp); + FILEDESC_SUNLOCK(fdp); + vp = fp->f_vnode; + switch (flp->l_type) { + case F_RDLCK: + if ((fp->f_flag & FREAD) == 0) { + error = EBADF; + break; + } + PROC_LOCK(p->p_leader); + p->p_leader->p_flag |= P_ADVLOCK; + PROC_UNLOCK(p->p_leader); + error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, + flp, flg); + break; + case F_WRLCK: + if ((fp->f_flag & FWRITE) == 0) { + error = EBADF; + break; + } + PROC_LOCK(p->p_leader); + p->p_leader->p_flag |= P_ADVLOCK; + PROC_UNLOCK(p->p_leader); + error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_SETLK, + flp, flg); + break; + case F_UNLCK: + error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_UNLCK, + flp, flg); + break; + case F_UNLCKSYS: + /* + * Temporary api for testing remote lock + * infrastructure. + */ + if (flg != F_REMOTE) { + error = EINVAL; + break; + } + error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, + F_UNLCKSYS, flp, flg); + break; + default: + error = EINVAL; + break; + } + if (error != 0 || flp->l_type == F_UNLCK || + flp->l_type == F_UNLCKSYS) { + fdrop(fp, td); + break; + } + + /* + * Check for a race with close. + * + * The vnode is now advisory locked (or unlocked, but this case + * is not really important) as the caller requested. + * We had to drop the filedesc lock, so we need to recheck if + * the descriptor is still valid, because if it was closed + * in the meantime we need to remove advisory lock from the + * vnode - close on any descriptor leading to an advisory + * locked vnode, removes that lock. + * We will return 0 on purpose in that case, as the result of + * successful advisory lock might have been externally visible + * already. This is fine - effectively we pretend to the caller + * that the closing thread was a bit slower and that the + * advisory lock succeeded before the close. + */ + FILEDESC_SLOCK(fdp); + if (fget_locked(fdp, fd) != fp) { + FILEDESC_SUNLOCK(fdp); + flp->l_whence = SEEK_SET; + flp->l_start = 0; + flp->l_len = 0; + flp->l_type = F_UNLCK; + (void) VOP_ADVLOCK(vp, (caddr_t)p->p_leader, + F_UNLCK, flp, F_POSIX); + } else + FILEDESC_SUNLOCK(fdp); + fdrop(fp, td); + break; + + case F_GETLK: + FILEDESC_SLOCK(fdp); + error = fdunwrap(fd, CAP_FLOCK, fdp, &fp); + if (error != 0) { + FILEDESC_SUNLOCK(fdp); + break; + } + if (fp->f_type != DTYPE_VNODE) { + FILEDESC_SUNLOCK(fdp); + error = EBADF; + break; + } + flp = (struct flock *)arg; + if (flp->l_type != F_RDLCK && flp->l_type != F_WRLCK && + flp->l_type != F_UNLCK) { + FILEDESC_SUNLOCK(fdp); + error = EINVAL; + break; + } + if (flp->l_whence == SEEK_CUR) { + foffset = foffset_get(fp); + if ((flp->l_start > 0 && + foffset > OFF_MAX - flp->l_start) || + (flp->l_start < 0 && + foffset < OFF_MIN - flp->l_start)) { + FILEDESC_SUNLOCK(fdp); + error = EOVERFLOW; + break; + } + flp->l_start += foffset; + } + /* + * VOP_ADVLOCK() may block. + */ + fhold(fp); + FILEDESC_SUNLOCK(fdp); + vp = fp->f_vnode; + error = VOP_ADVLOCK(vp, (caddr_t)p->p_leader, F_GETLK, flp, + F_POSIX); + fdrop(fp, td); + break; + + case F_RDAHEAD: + arg = arg ? 128 * 1024: 0; + /* FALLTHROUGH */ + case F_READAHEAD: + FILEDESC_SLOCK(fdp); + if ((fp = fget_locked(fdp, fd)) == NULL) { + FILEDESC_SUNLOCK(fdp); + error = EBADF; + break; + } + if (fp->f_type != DTYPE_VNODE) { + FILEDESC_SUNLOCK(fdp); + error = EBADF; + break; + } + fhold(fp); + FILEDESC_SUNLOCK(fdp); + if (arg != 0) { + vp = fp->f_vnode; + error = vn_lock(vp, LK_SHARED); + if (error != 0) + goto readahead_vnlock_fail; + bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; + VOP_UNLOCK(vp, 0); + fp->f_seqcount = (arg + bsize - 1) / bsize; + do { + new = old = fp->f_flag; + new |= FRDAHEAD; + } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); + readahead_vnlock_fail:; + } else { + do { + new = old = fp->f_flag; + new &= ~FRDAHEAD; + } while (!atomic_cmpset_rel_int(&fp->f_flag, old, new)); + } + fdrop(fp, td); + break; + + default: + error = EINVAL; + break; + } + return (error); +} + +/* + * Common code for dup, dup2, fcntl(F_DUPFD) and fcntl(F_DUP2FD). + */ +static int +do_dup(struct thread *td, int flags, int old, int new, + register_t *retval) +{ + struct filedesc *fdp; + struct proc *p; + struct file *fp; + struct file *delfp; + int error, maxfd; + + p = td->td_proc; + fdp = p->p_fd; + + /* + * Verify we have a valid descriptor to dup from and possibly to + * dup to. Unlike dup() and dup2(), fcntl()'s F_DUPFD should + * return EINVAL when the new descriptor is out of bounds. + */ + if (old < 0) + return (EBADF); + if (new < 0) + return (flags & DUP_FCNTL ? EINVAL : EBADF); + PROC_LOCK(p); + maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); + PROC_UNLOCK(p); + if (new >= maxfd) + return (flags & DUP_FCNTL ? EINVAL : EBADF); + + FILEDESC_XLOCK(fdp); + if (fget_locked(fdp, old) == NULL) { + FILEDESC_XUNLOCK(fdp); + return (EBADF); + } + if (flags & DUP_FIXED && old == new) { + *retval = new; + if (flags & DUP_CLOEXEC) + fdp->fd_ofileflags[new] |= UF_EXCLOSE; + FILEDESC_XUNLOCK(fdp); + return (0); + } + fp = fdp->fd_ofiles[old]; + fhold(fp); + + /* + * If the caller specified a file descriptor, make sure the file + * table is large enough to hold it, and grab it. Otherwise, just + * allocate a new descriptor the usual way. Since the filedesc + * lock may be temporarily dropped in the process, we have to look + * out for a race. + */ + if (flags & DUP_FIXED) { + if (new >= fdp->fd_nfiles) { + /* + * The resource limits are here instead of e.g. + * fdalloc(), because the file descriptor table may be + * shared between processes, so we can't really use + * racct_add()/racct_sub(). Instead of counting the + * number of actually allocated descriptors, just put + * the limit on the size of the file descriptor table. + */ +#ifdef RACCT + PROC_LOCK(p); + error = racct_set(p, RACCT_NOFILE, new + 1); + PROC_UNLOCK(p); + if (error != 0) { + FILEDESC_XUNLOCK(fdp); + fdrop(fp, td); + return (EMFILE); + } +#endif + fdgrowtable(fdp, new + 1); + } + if (fdp->fd_ofiles[new] == NULL) + fdused(fdp, new); + } else { + if ((error = fdalloc(td, new, &new)) != 0) { + FILEDESC_XUNLOCK(fdp); + fdrop(fp, td); + return (error); + } + } + + KASSERT(fp == fdp->fd_ofiles[old], ("old fd has been modified")); + KASSERT(old != new, ("new fd is same as old")); + + delfp = fdp->fd_ofiles[new]; + /* + * Duplicate the source descriptor. + */ + fdp->fd_ofiles[new] = fp; + if ((flags & DUP_CLOEXEC) != 0) + fdp->fd_ofileflags[new] = fdp->fd_ofileflags[old] | UF_EXCLOSE; + else + fdp->fd_ofileflags[new] = fdp->fd_ofileflags[old] & ~UF_EXCLOSE; + if (new > fdp->fd_lastfile) + fdp->fd_lastfile = new; + *retval = new; + + if (delfp != NULL) { + (void) closefp(fdp, new, delfp, td, 1); + /* closefp() drops the FILEDESC lock for us. */ + } else { + FILEDESC_XUNLOCK(fdp); + } + + return (0); +} + +/* + * If sigio is on the list associated with a process or process group, + * disable signalling from the device, remove sigio from the list and + * free sigio. + */ +void +funsetown(struct sigio **sigiop) +{ + struct sigio *sigio; + + SIGIO_LOCK(); + sigio = *sigiop; + if (sigio == NULL) { + SIGIO_UNLOCK(); + return; + } + *(sigio->sio_myref) = NULL; + if ((sigio)->sio_pgid < 0) { + struct pgrp *pg = (sigio)->sio_pgrp; + PGRP_LOCK(pg); + SLIST_REMOVE(&sigio->sio_pgrp->pg_sigiolst, sigio, + sigio, sio_pgsigio); + PGRP_UNLOCK(pg); + } else { + struct proc *p = (sigio)->sio_proc; + PROC_LOCK(p); + SLIST_REMOVE(&sigio->sio_proc->p_sigiolst, sigio, + sigio, sio_pgsigio); + PROC_UNLOCK(p); + } + SIGIO_UNLOCK(); + crfree(sigio->sio_ucred); + free(sigio, M_SIGIO); +} + +/* + * Free a list of sigio structures. + * We only need to lock the SIGIO_LOCK because we have made ourselves + * inaccessible to callers of fsetown and therefore do not need to lock + * the proc or pgrp struct for the list manipulation. + */ +void +funsetownlst(struct sigiolst *sigiolst) +{ + struct proc *p; + struct pgrp *pg; + struct sigio *sigio; + + sigio = SLIST_FIRST(sigiolst); + if (sigio == NULL) + return; + p = NULL; + pg = NULL; + + /* + * Every entry of the list should belong + * to a single proc or pgrp. + */ + if (sigio->sio_pgid < 0) { + pg = sigio->sio_pgrp; + PGRP_LOCK_ASSERT(pg, MA_NOTOWNED); + } else /* if (sigio->sio_pgid > 0) */ { + p = sigio->sio_proc; + PROC_LOCK_ASSERT(p, MA_NOTOWNED); + } + + SIGIO_LOCK(); + while ((sigio = SLIST_FIRST(sigiolst)) != NULL) { + *(sigio->sio_myref) = NULL; + if (pg != NULL) { + KASSERT(sigio->sio_pgid < 0, + ("Proc sigio in pgrp sigio list")); + KASSERT(sigio->sio_pgrp == pg, + ("Bogus pgrp in sigio list")); + PGRP_LOCK(pg); + SLIST_REMOVE(&pg->pg_sigiolst, sigio, sigio, + sio_pgsigio); + PGRP_UNLOCK(pg); + } else /* if (p != NULL) */ { + KASSERT(sigio->sio_pgid > 0, + ("Pgrp sigio in proc sigio list")); + KASSERT(sigio->sio_proc == p, + ("Bogus proc in sigio list")); + PROC_LOCK(p); + SLIST_REMOVE(&p->p_sigiolst, sigio, sigio, + sio_pgsigio); + PROC_UNLOCK(p); + } + SIGIO_UNLOCK(); + crfree(sigio->sio_ucred); + free(sigio, M_SIGIO); + SIGIO_LOCK(); + } + SIGIO_UNLOCK(); +} + +/* + * This is common code for FIOSETOWN ioctl called by fcntl(fd, F_SETOWN, arg). + * + * After permission checking, add a sigio structure to the sigio list for + * the process or process group. + */ +int +fsetown(pid_t pgid, struct sigio **sigiop) +{ + struct proc *proc; + struct pgrp *pgrp; + struct sigio *sigio; + int ret; + + if (pgid == 0) { + funsetown(sigiop); + return (0); + } + + ret = 0; + + /* Allocate and fill in the new sigio out of locks. */ + sigio = malloc(sizeof(struct sigio), M_SIGIO, M_WAITOK); + sigio->sio_pgid = pgid; + sigio->sio_ucred = crhold(curthread->td_ucred); + sigio->sio_myref = sigiop; + + sx_slock(&proctree_lock); + if (pgid > 0) { + proc = pfind(pgid); + if (proc == NULL) { + ret = ESRCH; + goto fail; + } + + /* + * Policy - Don't allow a process to FSETOWN a process + * in another session. + * + * Remove this test to allow maximum flexibility or + * restrict FSETOWN to the current process or process + * group for maximum safety. + */ + PROC_UNLOCK(proc); + if (proc->p_session != curthread->td_proc->p_session) { + ret = EPERM; + goto fail; + } + + pgrp = NULL; + } else /* if (pgid < 0) */ { + pgrp = pgfind(-pgid); + if (pgrp == NULL) { + ret = ESRCH; + goto fail; + } + PGRP_UNLOCK(pgrp); + + /* + * Policy - Don't allow a process to FSETOWN a process + * in another session. + * + * Remove this test to allow maximum flexibility or + * restrict FSETOWN to the current process or process + * group for maximum safety. + */ + if (pgrp->pg_session != curthread->td_proc->p_session) { + ret = EPERM; + goto fail; + } + + proc = NULL; + } + funsetown(sigiop); + if (pgid > 0) { + PROC_LOCK(proc); + /* + * Since funsetownlst() is called without the proctree + * locked, we need to check for P_WEXIT. + * XXX: is ESRCH correct? + */ + if ((proc->p_flag & P_WEXIT) != 0) { + PROC_UNLOCK(proc); + ret = ESRCH; + goto fail; + } + SLIST_INSERT_HEAD(&proc->p_sigiolst, sigio, sio_pgsigio); + sigio->sio_proc = proc; + PROC_UNLOCK(proc); + } else { + PGRP_LOCK(pgrp); + SLIST_INSERT_HEAD(&pgrp->pg_sigiolst, sigio, sio_pgsigio); + sigio->sio_pgrp = pgrp; + PGRP_UNLOCK(pgrp); + } + sx_sunlock(&proctree_lock); + SIGIO_LOCK(); + *sigiop = sigio; + SIGIO_UNLOCK(); + return (0); + +fail: + sx_sunlock(&proctree_lock); + crfree(sigio->sio_ucred); + free(sigio, M_SIGIO); + return (ret); +} + +/* + * This is common code for FIOGETOWN ioctl called by fcntl(fd, F_GETOWN, arg). + */ +pid_t +fgetown(sigiop) + struct sigio **sigiop; +{ + pid_t pgid; + + SIGIO_LOCK(); + pgid = (*sigiop != NULL) ? (*sigiop)->sio_pgid : 0; + SIGIO_UNLOCK(); + return (pgid); +} + +/* + * Function drops the filedesc lock on return. + */ +static int +closefp(struct filedesc *fdp, int fd, struct file *fp, struct thread *td, + int holdleaders) +{ + struct file *fp_object; + int error; + + FILEDESC_XLOCK_ASSERT(fdp); + + if (holdleaders) { + if (td->td_proc->p_fdtol != NULL) { + /* + * Ask fdfree() to sleep to ensure that all relevant + * process leaders can be traversed in closef(). + */ + fdp->fd_holdleaderscount++; + } else { + holdleaders = 0; + } + } + + /* + * We now hold the fp reference that used to be owned by the + * descriptor array. We have to unlock the FILEDESC *AFTER* + * knote_fdclose to prevent a race of the fd getting opened, a knote + * added, and deleteing a knote for the new fd. + */ + knote_fdclose(td, fd); + + /* + * When we're closing an fd with a capability, we need to notify + * mqueue if the underlying object is of type mqueue. + */ + (void)cap_funwrap(fp, 0, &fp_object); + if (fp_object->f_type == DTYPE_MQUEUE) + mq_fdclose(td, fd, fp_object); + FILEDESC_XUNLOCK(fdp); + + error = closef(fp, td); + if (holdleaders) { + FILEDESC_XLOCK(fdp); + fdp->fd_holdleaderscount--; + if (fdp->fd_holdleaderscount == 0 && + fdp->fd_holdleaderswakeup != 0) { + fdp->fd_holdleaderswakeup = 0; + wakeup(&fdp->fd_holdleaderscount); + } + FILEDESC_XUNLOCK(fdp); + } + return (error); +} + +/* + * Close a file descriptor. + */ +#ifndef _SYS_SYSPROTO_H_ +struct close_args { + int fd; +}; +#endif +/* ARGSUSED */ +int +sys_close(td, uap) + struct thread *td; + struct close_args *uap; +{ + + return (kern_close(td, uap->fd)); +} + +int +kern_close(td, fd) + struct thread *td; + int fd; +{ + struct filedesc *fdp; + struct file *fp; + + fdp = td->td_proc->p_fd; + + AUDIT_SYSCLOSE(td, fd); + + FILEDESC_XLOCK(fdp); + if ((fp = fget_locked(fdp, fd)) == NULL) { + FILEDESC_XUNLOCK(fdp); + return (EBADF); + } + fdp->fd_ofiles[fd] = NULL; + fdp->fd_ofileflags[fd] = 0; + fdunused(fdp, fd); + + /* closefp() drops the FILEDESC lock for us. */ + return (closefp(fdp, fd, fp, td, 1)); +} + +/* + * Close open file descriptors. + */ +#ifndef _SYS_SYSPROTO_H_ +struct closefrom_args { + int lowfd; +}; +#endif +/* ARGSUSED */ +int +sys_closefrom(struct thread *td, struct closefrom_args *uap) +{ + struct filedesc *fdp; + int fd; + + fdp = td->td_proc->p_fd; + AUDIT_ARG_FD(uap->lowfd); + + /* + * Treat negative starting file descriptor values identical to + * closefrom(0) which closes all files. + */ + if (uap->lowfd < 0) + uap->lowfd = 0; + FILEDESC_SLOCK(fdp); + for (fd = uap->lowfd; fd < fdp->fd_nfiles; fd++) { + if (fdp->fd_ofiles[fd] != NULL) { + FILEDESC_SUNLOCK(fdp); + (void)kern_close(td, fd); + FILEDESC_SLOCK(fdp); + } + } + FILEDESC_SUNLOCK(fdp); + return (0); +} + +#if defined(COMPAT_43) +/* + * Return status information about a file descriptor. + */ +#ifndef _SYS_SYSPROTO_H_ +struct ofstat_args { + int fd; + struct ostat *sb; +}; +#endif +/* ARGSUSED */ +int +ofstat(struct thread *td, struct ofstat_args *uap) +{ + struct ostat oub; + struct stat ub; + int error; + + error = kern_fstat(td, uap->fd, &ub); + if (error == 0) { + cvtstat(&ub, &oub); + error = copyout(&oub, uap->sb, sizeof(oub)); + } + return (error); +} +#endif /* COMPAT_43 */ + +/* + * Return status information about a file descriptor. + */ +#ifndef _SYS_SYSPROTO_H_ +struct fstat_args { + int fd; + struct stat *sb; +}; +#endif +/* ARGSUSED */ +int +sys_fstat(struct thread *td, struct fstat_args *uap) +{ + struct stat ub; + int error; + + error = kern_fstat(td, uap->fd, &ub); + if (error == 0) + error = copyout(&ub, uap->sb, sizeof(ub)); + return (error); +} + +int +kern_fstat(struct thread *td, int fd, struct stat *sbp) +{ + struct file *fp; + int error; + + AUDIT_ARG_FD(fd); + + if ((error = fget(td, fd, CAP_FSTAT, &fp)) != 0) + return (error); + + AUDIT_ARG_FILE(td->td_proc, fp); + + error = fo_stat(fp, sbp, td->td_ucred, td); + fdrop(fp, td); +#ifdef KTRACE + if (error == 0 && KTRPOINT(td, KTR_STRUCT)) + ktrstat(sbp); +#endif + return (error); +} + +/* + * Return status information about a file descriptor. + */ +#ifndef _SYS_SYSPROTO_H_ +struct nfstat_args { + int fd; + struct nstat *sb; +}; +#endif +/* ARGSUSED */ +int +sys_nfstat(struct thread *td, struct nfstat_args *uap) +{ + struct nstat nub; + struct stat ub; + int error; + + error = kern_fstat(td, uap->fd, &ub); + if (error == 0) { + cvtnstat(&ub, &nub); + error = copyout(&nub, uap->sb, sizeof(nub)); + } + return (error); +} + +/* + * Return pathconf information about a file descriptor. + */ +#ifndef _SYS_SYSPROTO_H_ +struct fpathconf_args { + int fd; + int name; +}; +#endif +/* ARGSUSED */ +int +sys_fpathconf(struct thread *td, struct fpathconf_args *uap) +{ + struct file *fp; + struct vnode *vp; + int error; + + if ((error = fget(td, uap->fd, CAP_FPATHCONF, &fp)) != 0) + return (error); + + /* If asynchronous I/O is available, it works for all descriptors. */ + if (uap->name == _PC_ASYNC_IO) { + td->td_retval[0] = async_io_version; + goto out; + } + vp = fp->f_vnode; + if (vp != NULL) { + vn_lock(vp, LK_SHARED | LK_RETRY); + error = VOP_PATHCONF(vp, uap->name, td->td_retval); + VOP_UNLOCK(vp, 0); + } else if (fp->f_type == DTYPE_PIPE || fp->f_type == DTYPE_SOCKET) { + if (uap->name != _PC_PIPE_BUF) { + error = EINVAL; + } else { + td->td_retval[0] = PIPE_BUF; + error = 0; + } + } else { + error = EOPNOTSUPP; + } +out: + fdrop(fp, td); + return (error); +} + +/* + * Grow the file table to accomodate (at least) nfd descriptors. + */ +static void +fdgrowtable(struct filedesc *fdp, int nfd) +{ + struct filedesc0 *fdp0; + struct freetable *fo; + struct file **ntable; + struct file **otable; + char *nfileflags; + int nnfiles, onfiles; + NDSLOTTYPE *nmap; + + FILEDESC_XLOCK_ASSERT(fdp); + + KASSERT(fdp->fd_nfiles > 0, + ("zero-length file table")); + + /* compute the size of the new table */ + onfiles = fdp->fd_nfiles; + nnfiles = NDSLOTS(nfd) * NDENTRIES; /* round up */ + if (nnfiles <= onfiles) + /* the table is already large enough */ + return; + + /* allocate a new table and (if required) new bitmaps */ + ntable = malloc((nnfiles * OFILESIZE) + sizeof(struct freetable), + M_FILEDESC, M_ZERO | M_WAITOK); + nfileflags = (char *)&ntable[nnfiles]; + if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) + nmap = malloc(NDSLOTS(nnfiles) * NDSLOTSIZE, + M_FILEDESC, M_ZERO | M_WAITOK); + else + nmap = NULL; + + bcopy(fdp->fd_ofiles, ntable, onfiles * sizeof(*ntable)); + bcopy(fdp->fd_ofileflags, nfileflags, onfiles); + otable = fdp->fd_ofiles; + fdp->fd_ofileflags = nfileflags; + fdp->fd_ofiles = ntable; + /* + * We must preserve ofiles until the process exits because we can't + * be certain that no threads have references to the old table via + * _fget(). + */ + if (onfiles > NDFILE) { + fo = (struct freetable *)&otable[onfiles]; + fdp0 = (struct filedesc0 *)fdp; + fo->ft_table = otable; + SLIST_INSERT_HEAD(&fdp0->fd_free, fo, ft_next); + } + if (NDSLOTS(nnfiles) > NDSLOTS(onfiles)) { + bcopy(fdp->fd_map, nmap, NDSLOTS(onfiles) * sizeof(*nmap)); + if (NDSLOTS(onfiles) > NDSLOTS(NDFILE)) + free(fdp->fd_map, M_FILEDESC); + fdp->fd_map = nmap; + } + fdp->fd_nfiles = nnfiles; +} + +/* + * Allocate a file descriptor for the process. + */ +int +fdalloc(struct thread *td, int minfd, int *result) +{ + struct proc *p = td->td_proc; + struct filedesc *fdp = p->p_fd; + int fd = -1, maxfd, allocfd; +#ifdef RACCT + int error; +#endif + + FILEDESC_XLOCK_ASSERT(fdp); + + if (fdp->fd_freefile > minfd) + minfd = fdp->fd_freefile; + + PROC_LOCK(p); + maxfd = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); + PROC_UNLOCK(p); + + /* + * Search the bitmap for a free descriptor starting at minfd. + * If none is found, grow the file table. + */ + fd = fd_first_free(fdp, minfd, fdp->fd_nfiles); + if (fd >= maxfd) + return (EMFILE); + if (fd >= fdp->fd_nfiles) { + allocfd = min(fd * 2, maxfd); +#ifdef RACCT + PROC_LOCK(p); + error = racct_set(p, RACCT_NOFILE, allocfd); + PROC_UNLOCK(p); + if (error != 0) + return (EMFILE); +#endif + /* + * fd is already equal to first free descriptor >= minfd, so + * we only need to grow the table and we are done. + */ + fdgrowtable(fdp, allocfd); + } + + /* + * Perform some sanity checks, then mark the file descriptor as + * used and return it to the caller. + */ + KASSERT(fd >= 0 && fd < min(maxfd, fdp->fd_nfiles), + ("invalid descriptor %d", fd)); + KASSERT(!fdisused(fdp, fd), + ("fd_first_free() returned non-free descriptor")); + KASSERT(fdp->fd_ofiles[fd] == NULL, ("file descriptor isn't free")); + KASSERT(fdp->fd_ofileflags[fd] == 0, ("file flags are set")); + fdused(fdp, fd); + *result = fd; + return (0); +} + +/* + * Check to see whether n user file descriptors are available to the process + * p. + */ +int +fdavail(struct thread *td, int n) +{ + struct proc *p = td->td_proc; + struct filedesc *fdp = td->td_proc->p_fd; + int i, lim, last; + + FILEDESC_LOCK_ASSERT(fdp); + + /* + * XXX: This is only called from uipc_usrreq.c:unp_externalize(); + * call racct_add() from there instead of dealing with containers + * here. + */ + PROC_LOCK(p); + lim = min((int)lim_cur(p, RLIMIT_NOFILE), maxfilesperproc); + PROC_UNLOCK(p); + if ((i = lim - fdp->fd_nfiles) > 0 && (n -= i) <= 0) + return (1); + last = min(fdp->fd_nfiles, lim); + for (i = fdp->fd_freefile; i < last; i++) { + if (fdp->fd_ofiles[i] == NULL && --n <= 0) + return (1); + } + return (0); +} + +/* + * Create a new open file structure and allocate a file decriptor for the + * process that refers to it. We add one reference to the file for the + * descriptor table and one reference for resultfp. This is to prevent us + * being preempted and the entry in the descriptor table closed after we + * release the FILEDESC lock. + */ +int +falloc(struct thread *td, struct file **resultfp, int *resultfd, int flags) +{ + struct file *fp; + int error, fd; + + error = falloc_noinstall(td, &fp); + if (error) + return (error); /* no reference held on error */ + + error = finstall(td, fp, &fd, flags); + if (error) { + fdrop(fp, td); /* one reference (fp only) */ + return (error); + } + + if (resultfp != NULL) + *resultfp = fp; /* copy out result */ + else + fdrop(fp, td); /* release local reference */ + + if (resultfd != NULL) + *resultfd = fd; + + return (0); +} + +/* + * Create a new open file structure without allocating a file descriptor. + */ +int +falloc_noinstall(struct thread *td, struct file **resultfp) +{ + struct file *fp; + int maxuserfiles = maxfiles - (maxfiles / 20); + static struct timeval lastfail; + static int curfail; + + KASSERT(resultfp != NULL, ("%s: resultfp == NULL", __func__)); + + if ((openfiles >= maxuserfiles && + priv_check(td, PRIV_MAXFILES) != 0) || + openfiles >= maxfiles) { + if (ppsratecheck(&lastfail, &curfail, 1)) { + printf("kern.maxfiles limit exceeded by uid %i, " + "please see tuning(7).\n", td->td_ucred->cr_ruid); + } + return (ENFILE); + } + atomic_add_int(&openfiles, 1); + fp = uma_zalloc(file_zone, M_WAITOK | M_ZERO); + refcount_init(&fp->f_count, 1); + fp->f_cred = crhold(td->td_ucred); + fp->f_ops = &badfileops; + fp->f_data = NULL; + fp->f_vnode = NULL; + *resultfp = fp; + return (0); +} + +/* + * Install a file in a file descriptor table. + */ +int +finstall(struct thread *td, struct file *fp, int *fd, int flags) +{ + struct filedesc *fdp = td->td_proc->p_fd; + int error; + + KASSERT(fd != NULL, ("%s: fd == NULL", __func__)); + KASSERT(fp != NULL, ("%s: fp == NULL", __func__)); + + FILEDESC_XLOCK(fdp); + if ((error = fdalloc(td, 0, fd))) { + FILEDESC_XUNLOCK(fdp); + return (error); + } + fhold(fp); + fdp->fd_ofiles[*fd] = fp; + if ((flags & O_CLOEXEC) != 0) + fdp->fd_ofileflags[*fd] |= UF_EXCLOSE; + FILEDESC_XUNLOCK(fdp); + return (0); +} + +/* + * Build a new filedesc structure from another. + * Copy the current, root, and jail root vnode references. + */ +struct filedesc * +fdinit(struct filedesc *fdp) +{ + struct filedesc0 *newfdp; + + newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO); + FILEDESC_LOCK_INIT(&newfdp->fd_fd); + if (fdp != NULL) { + FILEDESC_XLOCK(fdp); + newfdp->fd_fd.fd_cdir = fdp->fd_cdir; + if (newfdp->fd_fd.fd_cdir) + VREF(newfdp->fd_fd.fd_cdir); + newfdp->fd_fd.fd_rdir = fdp->fd_rdir; + if (newfdp->fd_fd.fd_rdir) + VREF(newfdp->fd_fd.fd_rdir); + newfdp->fd_fd.fd_jdir = fdp->fd_jdir; + if (newfdp->fd_fd.fd_jdir) + VREF(newfdp->fd_fd.fd_jdir); + FILEDESC_XUNLOCK(fdp); + } + + /* Create the file descriptor table. */ + newfdp->fd_fd.fd_refcnt = 1; + newfdp->fd_fd.fd_holdcnt = 1; + newfdp->fd_fd.fd_cmask = CMASK; + newfdp->fd_fd.fd_ofiles = newfdp->fd_dfiles; + newfdp->fd_fd.fd_ofileflags = newfdp->fd_dfileflags; + newfdp->fd_fd.fd_nfiles = NDFILE; + newfdp->fd_fd.fd_map = newfdp->fd_dmap; + newfdp->fd_fd.fd_lastfile = -1; + return (&newfdp->fd_fd); +} + +static struct filedesc * +fdhold(struct proc *p) +{ + struct filedesc *fdp; + + mtx_lock(&fdesc_mtx); + fdp = p->p_fd; + if (fdp != NULL) + fdp->fd_holdcnt++; + mtx_unlock(&fdesc_mtx); + return (fdp); +} + +static void +fddrop(struct filedesc *fdp) +{ + struct filedesc0 *fdp0; + struct freetable *ft; + int i; + + mtx_lock(&fdesc_mtx); + i = --fdp->fd_holdcnt; + mtx_unlock(&fdesc_mtx); + if (i > 0) + return; + + FILEDESC_LOCK_DESTROY(fdp); + fdp0 = (struct filedesc0 *)fdp; + while ((ft = SLIST_FIRST(&fdp0->fd_free)) != NULL) { + SLIST_REMOVE_HEAD(&fdp0->fd_free, ft_next); + free(ft->ft_table, M_FILEDESC); + } + free(fdp, M_FILEDESC); +} + +/* + * Share a filedesc structure. + */ +struct filedesc * +fdshare(struct filedesc *fdp) +{ + + FILEDESC_XLOCK(fdp); + fdp->fd_refcnt++; + FILEDESC_XUNLOCK(fdp); + return (fdp); +} + +/* + * Unshare a filedesc structure, if necessary by making a copy + */ +void +fdunshare(struct proc *p, struct thread *td) +{ + + FILEDESC_XLOCK(p->p_fd); + if (p->p_fd->fd_refcnt > 1) { + struct filedesc *tmp; + + FILEDESC_XUNLOCK(p->p_fd); + tmp = fdcopy(p->p_fd); + fdfree(td); + p->p_fd = tmp; + } else + FILEDESC_XUNLOCK(p->p_fd); +} + +/* + * Copy a filedesc structure. A NULL pointer in returns a NULL reference, + * this is to ease callers, not catch errors. + */ +struct filedesc * +fdcopy(struct filedesc *fdp) +{ + struct filedesc *newfdp; + int i; + + /* Certain daemons might not have file descriptors. */ + if (fdp == NULL) + return (NULL); + + newfdp = fdinit(fdp); + FILEDESC_SLOCK(fdp); + while (fdp->fd_lastfile >= newfdp->fd_nfiles) { + FILEDESC_SUNLOCK(fdp); + FILEDESC_XLOCK(newfdp); + fdgrowtable(newfdp, fdp->fd_lastfile + 1); + FILEDESC_XUNLOCK(newfdp); + FILEDESC_SLOCK(fdp); + } + /* copy all passable descriptors (i.e. not kqueue) */ + newfdp->fd_freefile = -1; + for (i = 0; i <= fdp->fd_lastfile; ++i) { + if (fdisused(fdp, i) && + (fdp->fd_ofiles[i]->f_ops->fo_flags & DFLAG_PASSABLE) && + fdp->fd_ofiles[i]->f_ops != &badfileops) { + newfdp->fd_ofiles[i] = fdp->fd_ofiles[i]; + newfdp->fd_ofileflags[i] = fdp->fd_ofileflags[i]; + fhold(newfdp->fd_ofiles[i]); + newfdp->fd_lastfile = i; + } else { + if (newfdp->fd_freefile == -1) + newfdp->fd_freefile = i; + } + } + newfdp->fd_cmask = fdp->fd_cmask; + FILEDESC_SUNLOCK(fdp); + FILEDESC_XLOCK(newfdp); + for (i = 0; i <= newfdp->fd_lastfile; ++i) + if (newfdp->fd_ofiles[i] != NULL) + fdused(newfdp, i); + if (newfdp->fd_freefile == -1) + newfdp->fd_freefile = i; + FILEDESC_XUNLOCK(newfdp); + return (newfdp); +} + +/* + * Release a filedesc structure. + */ +void +fdfree(struct thread *td) +{ + struct filedesc *fdp; + int i; + struct filedesc_to_leader *fdtol; + struct file *fp; + struct vnode *cdir, *jdir, *rdir, *vp; + struct flock lf; + + /* Certain daemons might not have file descriptors. */ + fdp = td->td_proc->p_fd; + if (fdp == NULL) + return; + +#ifdef RACCT + PROC_LOCK(td->td_proc); + racct_set(td->td_proc, RACCT_NOFILE, 0); + PROC_UNLOCK(td->td_proc); +#endif + + /* Check for special need to clear POSIX style locks */ + fdtol = td->td_proc->p_fdtol; + if (fdtol != NULL) { + FILEDESC_XLOCK(fdp); + KASSERT(fdtol->fdl_refcount > 0, + ("filedesc_to_refcount botch: fdl_refcount=%d", + fdtol->fdl_refcount)); + if (fdtol->fdl_refcount == 1 && + (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { + for (i = 0; i <= fdp->fd_lastfile; i++) { + fp = fdp->fd_ofiles[i]; + if (fp == NULL || fp->f_type != DTYPE_VNODE) + continue; + fhold(fp); + FILEDESC_XUNLOCK(fdp); + lf.l_whence = SEEK_SET; + lf.l_start = 0; + lf.l_len = 0; + lf.l_type = F_UNLCK; + vp = fp->f_vnode; + (void) VOP_ADVLOCK(vp, + (caddr_t)td->td_proc->p_leader, F_UNLCK, + &lf, F_POSIX); + FILEDESC_XLOCK(fdp); + fdrop(fp, td); + } + } + retry: + if (fdtol->fdl_refcount == 1) { + if (fdp->fd_holdleaderscount > 0 && + (td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { + /* + * close() or do_dup() has cleared a reference + * in a shared file descriptor table. + */ + fdp->fd_holdleaderswakeup = 1; + sx_sleep(&fdp->fd_holdleaderscount, + FILEDESC_LOCK(fdp), PLOCK, "fdlhold", 0); + goto retry; + } + if (fdtol->fdl_holdcount > 0) { + /* + * Ensure that fdtol->fdl_leader remains + * valid in closef(). + */ + fdtol->fdl_wakeup = 1; + sx_sleep(fdtol, FILEDESC_LOCK(fdp), PLOCK, + "fdlhold", 0); + goto retry; + } + } + fdtol->fdl_refcount--; + if (fdtol->fdl_refcount == 0 && + fdtol->fdl_holdcount == 0) { + fdtol->fdl_next->fdl_prev = fdtol->fdl_prev; + fdtol->fdl_prev->fdl_next = fdtol->fdl_next; + } else + fdtol = NULL; + td->td_proc->p_fdtol = NULL; + FILEDESC_XUNLOCK(fdp); + if (fdtol != NULL) + free(fdtol, M_FILEDESC_TO_LEADER); + } + FILEDESC_XLOCK(fdp); + i = --fdp->fd_refcnt; + FILEDESC_XUNLOCK(fdp); + if (i > 0) + return; + + for (i = 0; i <= fdp->fd_lastfile; i++) { + fp = fdp->fd_ofiles[i]; + if (fp != NULL) { + FILEDESC_XLOCK(fdp); + fdp->fd_ofiles[i] = NULL; + FILEDESC_XUNLOCK(fdp); + (void) closef(fp, td); + } + } + FILEDESC_XLOCK(fdp); + + /* XXX This should happen earlier. */ + mtx_lock(&fdesc_mtx); + td->td_proc->p_fd = NULL; + mtx_unlock(&fdesc_mtx); + + if (fdp->fd_nfiles > NDFILE) + free(fdp->fd_ofiles, M_FILEDESC); + if (NDSLOTS(fdp->fd_nfiles) > NDSLOTS(NDFILE)) + free(fdp->fd_map, M_FILEDESC); + + fdp->fd_nfiles = 0; + + cdir = fdp->fd_cdir; + fdp->fd_cdir = NULL; + rdir = fdp->fd_rdir; + fdp->fd_rdir = NULL; + jdir = fdp->fd_jdir; + fdp->fd_jdir = NULL; + FILEDESC_XUNLOCK(fdp); + + if (cdir) + vrele(cdir); + if (rdir) + vrele(rdir); + if (jdir) + vrele(jdir); + + fddrop(fdp); +} + +/* + * For setugid programs, we don't want to people to use that setugidness + * to generate error messages which write to a file which otherwise would + * otherwise be off-limits to the process. We check for filesystems where + * the vnode can change out from under us after execve (like [lin]procfs). + * + * Since setugidsafety calls this only for fd 0, 1 and 2, this check is + * sufficient. We also don't check for setugidness since we know we are. + */ +static int +is_unsafe(struct file *fp) +{ + if (fp->f_type == DTYPE_VNODE) { + struct vnode *vp = fp->f_vnode; + + if ((vp->v_vflag & VV_PROCDEP) != 0) + return (1); + } + return (0); +} + +/* + * Make this setguid thing safe, if at all possible. + */ +void +setugidsafety(struct thread *td) +{ + struct filedesc *fdp; + int i; + + /* Certain daemons might not have file descriptors. */ + fdp = td->td_proc->p_fd; + if (fdp == NULL) + return; + + /* + * Note: fdp->fd_ofiles may be reallocated out from under us while + * we are blocked in a close. Be careful! + */ + FILEDESC_XLOCK(fdp); + for (i = 0; i <= fdp->fd_lastfile; i++) { + if (i > 2) + break; + if (fdp->fd_ofiles[i] && is_unsafe(fdp->fd_ofiles[i])) { + struct file *fp; + + knote_fdclose(td, i); + /* + * NULL-out descriptor prior to close to avoid + * a race while close blocks. + */ + fp = fdp->fd_ofiles[i]; + fdp->fd_ofiles[i] = NULL; + fdp->fd_ofileflags[i] = 0; + fdunused(fdp, i); + FILEDESC_XUNLOCK(fdp); + (void) closef(fp, td); + FILEDESC_XLOCK(fdp); + } + } + FILEDESC_XUNLOCK(fdp); +} + +/* + * If a specific file object occupies a specific file descriptor, close the + * file descriptor entry and drop a reference on the file object. This is a + * convenience function to handle a subsequent error in a function that calls + * falloc() that handles the race that another thread might have closed the + * file descriptor out from under the thread creating the file object. + */ +void +fdclose(struct filedesc *fdp, struct file *fp, int idx, struct thread *td) +{ + + FILEDESC_XLOCK(fdp); + if (fdp->fd_ofiles[idx] == fp) { + fdp->fd_ofiles[idx] = NULL; + fdunused(fdp, idx); + FILEDESC_XUNLOCK(fdp); + fdrop(fp, td); + } else + FILEDESC_XUNLOCK(fdp); +} + +/* + * Close any files on exec? + */ +void +fdcloseexec(struct thread *td) +{ + struct filedesc *fdp; + struct file *fp; + int i; + + /* Certain daemons might not have file descriptors. */ + fdp = td->td_proc->p_fd; + if (fdp == NULL) + return; + + /* + * We cannot cache fd_ofiles or fd_ofileflags since operations + * may block and rip them out from under us. + */ + FILEDESC_XLOCK(fdp); + for (i = 0; i <= fdp->fd_lastfile; i++) { + fp = fdp->fd_ofiles[i]; + if (fp != NULL && (fp->f_type == DTYPE_MQUEUE || + (fdp->fd_ofileflags[i] & UF_EXCLOSE))) { + fdp->fd_ofiles[i] = NULL; + fdp->fd_ofileflags[i] = 0; + fdunused(fdp, i); + (void) closefp(fdp, i, fp, td, 0); + /* closefp() drops the FILEDESC lock. */ + FILEDESC_XLOCK(fdp); + } + } + FILEDESC_XUNLOCK(fdp); +} + +/* + * It is unsafe for set[ug]id processes to be started with file + * descriptors 0..2 closed, as these descriptors are given implicit + * significance in the Standard C library. fdcheckstd() will create a + * descriptor referencing /dev/null for each of stdin, stdout, and + * stderr that is not already open. + */ +int +fdcheckstd(struct thread *td) +{ + struct filedesc *fdp; + register_t retval, save; + int i, error, devnull; + + fdp = td->td_proc->p_fd; + if (fdp == NULL) + return (0); + KASSERT(fdp->fd_refcnt == 1, ("the fdtable should not be shared")); + devnull = -1; + error = 0; + for (i = 0; i < 3; i++) { + if (fdp->fd_ofiles[i] != NULL) + continue; + if (devnull < 0) { + save = td->td_retval[0]; + error = kern_open(td, "/dev/null", UIO_SYSSPACE, + O_RDWR, 0); + devnull = td->td_retval[0]; + td->td_retval[0] = save; + if (error) + break; + KASSERT(devnull == i, ("oof, we didn't get our fd")); + } else { + error = do_dup(td, DUP_FIXED, devnull, i, &retval); + if (error != 0) + break; + } + } + return (error); +} + +/* + * Internal form of close. Decrement reference count on file structure. + * Note: td may be NULL when closing a file that was being passed in a + * message. + * + * XXXRW: Giant is not required for the caller, but often will be held; this + * makes it moderately likely the Giant will be recursed in the VFS case. + */ +int +closef(struct file *fp, struct thread *td) +{ + struct vnode *vp; + struct flock lf; + struct filedesc_to_leader *fdtol; + struct filedesc *fdp; + struct file *fp_object; + + /* + * POSIX record locking dictates that any close releases ALL + * locks owned by this process. This is handled by setting + * a flag in the unlock to free ONLY locks obeying POSIX + * semantics, and not to free BSD-style file locks. + * If the descriptor was in a message, POSIX-style locks + * aren't passed with the descriptor, and the thread pointer + * will be NULL. Callers should be careful only to pass a + * NULL thread pointer when there really is no owning + * context that might have locks, or the locks will be + * leaked. + * + * If this is a capability, we do lock processing under the underlying + * node, not the capability itself. + */ + (void)cap_funwrap(fp, 0, &fp_object); + if (fp_object->f_type == DTYPE_VNODE && td != NULL) { + vp = fp_object->f_vnode; + if ((td->td_proc->p_leader->p_flag & P_ADVLOCK) != 0) { + lf.l_whence = SEEK_SET; + lf.l_start = 0; + lf.l_len = 0; + lf.l_type = F_UNLCK; + (void) VOP_ADVLOCK(vp, (caddr_t)td->td_proc->p_leader, + F_UNLCK, &lf, F_POSIX); + } + fdtol = td->td_proc->p_fdtol; + if (fdtol != NULL) { + /* + * Handle special case where file descriptor table is + * shared between multiple process leaders. + */ + fdp = td->td_proc->p_fd; + FILEDESC_XLOCK(fdp); + for (fdtol = fdtol->fdl_next; + fdtol != td->td_proc->p_fdtol; + fdtol = fdtol->fdl_next) { + if ((fdtol->fdl_leader->p_flag & + P_ADVLOCK) == 0) + continue; + fdtol->fdl_holdcount++; + FILEDESC_XUNLOCK(fdp); + lf.l_whence = SEEK_SET; + lf.l_start = 0; + lf.l_len = 0; + lf.l_type = F_UNLCK; + vp = fp_object->f_vnode; + (void) VOP_ADVLOCK(vp, + (caddr_t)fdtol->fdl_leader, F_UNLCK, &lf, + F_POSIX); + FILEDESC_XLOCK(fdp); + fdtol->fdl_holdcount--; + if (fdtol->fdl_holdcount == 0 && + fdtol->fdl_wakeup != 0) { + fdtol->fdl_wakeup = 0; + wakeup(fdtol); + } + } + FILEDESC_XUNLOCK(fdp); + } + } + return (fdrop(fp, td)); +} + +/* + * Initialize the file pointer with the specified properties. + * + * The ops are set with release semantics to be certain that the flags, type, + * and data are visible when ops is. This is to prevent ops methods from being + * called with bad data. + */ +void +finit(struct file *fp, u_int flag, short type, void *data, struct fileops *ops) +{ + fp->f_data = data; + fp->f_flag = flag; + fp->f_type = type; + atomic_store_rel_ptr((volatile uintptr_t *)&fp->f_ops, (uintptr_t)ops); +} + +struct file * +fget_unlocked(struct filedesc *fdp, int fd) +{ + struct file *fp; + u_int count; + + if (fd < 0 || fd >= fdp->fd_nfiles) + return (NULL); + /* + * Fetch the descriptor locklessly. We avoid fdrop() races by + * never raising a refcount above 0. To accomplish this we have + * to use a cmpset loop rather than an atomic_add. The descriptor + * must be re-verified once we acquire a reference to be certain + * that the identity is still correct and we did not lose a race + * due to preemption. + */ + for (;;) { + fp = fdp->fd_ofiles[fd]; + if (fp == NULL) + break; + count = fp->f_count; + if (count == 0) + continue; + /* + * Use an acquire barrier to prevent caching of fd_ofiles + * so it is refreshed for verification. + */ + if (atomic_cmpset_acq_int(&fp->f_count, count, count + 1) != 1) + continue; + if (fp == fdp->fd_ofiles[fd]) + break; + fdrop(fp, curthread); + } + + return (fp); +} + +/* + * Extract the file pointer associated with the specified descriptor for the + * current user process. + * + * If the descriptor doesn't exist or doesn't match 'flags', EBADF is + * returned. + * + * If the FGET_GETCAP flag is set, the capability itself will be returned. + * Calling _fget() with FGET_GETCAP on a non-capability will return EINVAL. + * Otherwise, if the file is a capability, its rights will be checked against + * the capability rights mask, and if successful, the object will be unwrapped. + * + * If an error occured the non-zero error is returned and *fpp is set to + * NULL. Otherwise *fpp is held and set and zero is returned. Caller is + * responsible for fdrop(). + */ +#define FGET_GETCAP 0x00000001 +static __inline int +_fget(struct thread *td, int fd, struct file **fpp, int flags, + cap_rights_t needrights, cap_rights_t *haverightsp, u_char *maxprotp, + int fget_flags) +{ + struct filedesc *fdp; + struct file *fp; +#ifdef CAPABILITIES + struct file *fp_fromcap; +#endif + int error; + + *fpp = NULL; + if (td == NULL || (fdp = td->td_proc->p_fd) == NULL) + return (EBADF); + if ((fp = fget_unlocked(fdp, fd)) == NULL) + return (EBADF); + if (fp->f_ops == &badfileops) { + fdrop(fp, td); + return (EBADF); + } + +#ifdef CAPABILITIES + /* + * If this is a capability, what rights does it have? + */ + if (haverightsp != NULL) { + if (fp->f_type == DTYPE_CAPABILITY) + *haverightsp = cap_rights(fp); + else + *haverightsp = CAP_MASK_VALID; + } + + /* + * If a capability has been requested, return the capability directly. + * Otherwise, check capability rights, extract the underlying object, + * and check its access flags. + */ + if (fget_flags & FGET_GETCAP) { + if (fp->f_type != DTYPE_CAPABILITY) { + fdrop(fp, td); + return (EINVAL); + } + } else { + if (maxprotp == NULL) + error = cap_funwrap(fp, needrights, &fp_fromcap); + else + error = cap_funwrap_mmap(fp, needrights, maxprotp, + &fp_fromcap); + if (error != 0) { + fdrop(fp, td); + return (error); + } + + /* + * If we've unwrapped a file, drop the original capability + * and hold the new descriptor. fp after this point refers to + * the actual (unwrapped) object, not the capability. + */ + if (fp != fp_fromcap) { + fhold(fp_fromcap); + fdrop(fp, td); + fp = fp_fromcap; + } + } +#else /* !CAPABILITIES */ + KASSERT(fp->f_type != DTYPE_CAPABILITY, + ("%s: saw capability", __func__)); + if (maxprotp != NULL) + *maxprotp = VM_PROT_ALL; +#endif /* CAPABILITIES */ + + /* + * FREAD and FWRITE failure return EBADF as per POSIX. + */ + error = 0; + switch (flags) { + case FREAD: + case FWRITE: + if ((fp->f_flag & flags) == 0) + error = EBADF; + break; + case FEXEC: + if ((fp->f_flag & (FREAD | FEXEC)) == 0 || + ((fp->f_flag & FWRITE) != 0)) + error = EBADF; + break; + case 0: + break; + default: + KASSERT(0, ("wrong flags")); + } + + if (error != 0) { + fdrop(fp, td); + return (error); + } + + *fpp = fp; + return (0); +} + +int +fget(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) +{ + + return(_fget(td, fd, fpp, 0, rights, NULL, NULL, 0)); +} + +int +fget_mmap(struct thread *td, int fd, cap_rights_t rights, u_char *maxprotp, + struct file **fpp) +{ + + return (_fget(td, fd, fpp, 0, rights, NULL, maxprotp, 0)); +} + +int +fget_read(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) +{ + + return(_fget(td, fd, fpp, FREAD, rights, NULL, NULL, 0)); +} + +int +fget_write(struct thread *td, int fd, cap_rights_t rights, struct file **fpp) +{ + + return (_fget(td, fd, fpp, FWRITE, rights, NULL, NULL, 0)); +} + +/* + * Unlike the other fget() calls, which accept and check capability rights + * but never return capabilities, fgetcap() returns the capability but doesn't + * check capability rights. + */ +int +fgetcap(struct thread *td, int fd, struct file **fpp) +{ + + return (_fget(td, fd, fpp, 0, 0, NULL, NULL, FGET_GETCAP)); +} + + +/* + * Like fget() but loads the underlying vnode, or returns an error if the + * descriptor does not represent a vnode. Note that pipes use vnodes but + * never have VM objects. The returned vnode will be vref()'d. + * + * XXX: what about the unused flags ? + */ +static __inline int +_fgetvp(struct thread *td, int fd, int flags, cap_rights_t needrights, + cap_rights_t *haverightsp, struct vnode **vpp) +{ + struct file *fp; + int error; + + *vpp = NULL; + if ((error = _fget(td, fd, &fp, flags, needrights, haverightsp, + NULL, 0)) != 0) + return (error); + if (fp->f_vnode == NULL) { + error = EINVAL; + } else { + *vpp = fp->f_vnode; + vref(*vpp); + } + fdrop(fp, td); + + return (error); +} + +int +fgetvp(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) +{ + + return (_fgetvp(td, fd, 0, rights, NULL, vpp)); +} + +int +fgetvp_rights(struct thread *td, int fd, cap_rights_t need, cap_rights_t *have, + struct vnode **vpp) +{ + return (_fgetvp(td, fd, 0, need, have, vpp)); +} + +int +fgetvp_read(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) +{ + + return (_fgetvp(td, fd, FREAD, rights, NULL, vpp)); +} + +int +fgetvp_exec(struct thread *td, int fd, cap_rights_t rights, struct vnode **vpp) +{ + + return (_fgetvp(td, fd, FEXEC, rights, NULL, vpp)); +} + +#ifdef notyet +int +fgetvp_write(struct thread *td, int fd, cap_rights_t rights, + struct vnode **vpp) +{ + + return (_fgetvp(td, fd, FWRITE, rights, NULL, vpp)); +} +#endif + +/* + * Like fget() but loads the underlying socket, or returns an error if the + * descriptor does not represent a socket. + * + * We bump the ref count on the returned socket. XXX Also obtain the SX lock + * in the future. + * + * Note: fgetsock() and fputsock() are deprecated, as consumers should rely + * on their file descriptor reference to prevent the socket from being free'd + * during use. + */ +int +fgetsock(struct thread *td, int fd, cap_rights_t rights, struct socket **spp, + u_int *fflagp) +{ + struct file *fp; + int error; + + *spp = NULL; + if (fflagp != NULL) + *fflagp = 0; + if ((error = _fget(td, fd, &fp, 0, rights, NULL, NULL, 0)) != 0) + return (error); + if (fp->f_type != DTYPE_SOCKET) { + error = ENOTSOCK; + } else { + *spp = fp->f_data; + if (fflagp) + *fflagp = fp->f_flag; + SOCK_LOCK(*spp); + soref(*spp); + SOCK_UNLOCK(*spp); + } + fdrop(fp, td); + + return (error); +} + +/* + * Drop the reference count on the socket and XXX release the SX lock in the + * future. The last reference closes the socket. + * + * Note: fputsock() is deprecated, see comment for fgetsock(). + */ +void +fputsock(struct socket *so) +{ + + ACCEPT_LOCK(); + SOCK_LOCK(so); + CURVNET_SET(so->so_vnet); + sorele(so); + CURVNET_RESTORE(); +} + +/* + * Handle the last reference to a file being closed. + * + * No special capability handling here, as the capability's fo_close will run + * instead of the object here, and perform any necessary drop on the object. + */ +int +_fdrop(struct file *fp, struct thread *td) +{ + int error; + + error = 0; + if (fp->f_count != 0) + panic("fdrop: count %d", fp->f_count); + if (fp->f_ops != &badfileops) + error = fo_close(fp, td); + atomic_subtract_int(&openfiles, 1); + crfree(fp->f_cred); + free(fp->f_advice, M_FADVISE); + uma_zfree(file_zone, fp); + + return (error); +} + +/* + * Apply an advisory lock on a file descriptor. + * + * Just attempt to get a record lock of the requested type on the entire file + * (l_whence = SEEK_SET, l_start = 0, l_len = 0). + */ +#ifndef _SYS_SYSPROTO_H_ +struct flock_args { + int fd; + int how; +}; +#endif +/* ARGSUSED */ +int +sys_flock(struct thread *td, struct flock_args *uap) +{ + struct file *fp; + struct vnode *vp; + struct flock lf; + int error; + + if ((error = fget(td, uap->fd, CAP_FLOCK, &fp)) != 0) + return (error); + if (fp->f_type != DTYPE_VNODE) { + fdrop(fp, td); + return (EOPNOTSUPP); + } + + vp = fp->f_vnode; + lf.l_whence = SEEK_SET; + lf.l_start = 0; + lf.l_len = 0; + if (uap->how & LOCK_UN) { + lf.l_type = F_UNLCK; + atomic_clear_int(&fp->f_flag, FHASLOCK); + error = VOP_ADVLOCK(vp, (caddr_t)fp, F_UNLCK, &lf, F_FLOCK); + goto done2; + } + if (uap->how & LOCK_EX) + lf.l_type = F_WRLCK; + else if (uap->how & LOCK_SH) + lf.l_type = F_RDLCK; + else { + error = EBADF; + goto done2; + } + atomic_set_int(&fp->f_flag, FHASLOCK); + error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, + (uap->how & LOCK_NB) ? F_FLOCK : F_FLOCK | F_WAIT); +done2: + fdrop(fp, td); + return (error); +} +/* + * Duplicate the specified descriptor to a free descriptor. + */ +int +dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, int openerror, int *indxp) +{ + struct file *fp; + int error, indx; + + KASSERT(openerror == ENODEV || openerror == ENXIO, + ("unexpected error %d in %s", openerror, __func__)); + + /* + * If the to-be-dup'd fd number is greater than the allowed number + * of file descriptors, or the fd to be dup'd has already been + * closed, then reject. + */ + FILEDESC_XLOCK(fdp); + if ((fp = fget_locked(fdp, dfd)) == NULL) { + FILEDESC_XUNLOCK(fdp); + return (EBADF); + } + + error = fdalloc(td, 0, &indx); + if (error != 0) { + FILEDESC_XUNLOCK(fdp); + return (error); + } + + /* + * There are two cases of interest here. + * + * For ENODEV simply dup (dfd) to file descriptor (indx) and return. + * + * For ENXIO steal away the file structure from (dfd) and store it in + * (indx). (dfd) is effectively closed by this operation. + */ + switch (openerror) { + case ENODEV: + /* + * Check that the mode the file is being opened for is a + * subset of the mode of the existing descriptor. + */ + if (((mode & (FREAD|FWRITE)) | fp->f_flag) != fp->f_flag) { + fdunused(fdp, indx); + FILEDESC_XUNLOCK(fdp); + return (EACCES); + } + fdp->fd_ofiles[indx] = fp; + fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd]; + fhold(fp); + break; + case ENXIO: + /* + * Steal away the file pointer from dfd and stuff it into indx. + */ + fdp->fd_ofiles[indx] = fp; + fdp->fd_ofiles[dfd] = NULL; + fdp->fd_ofileflags[indx] = fdp->fd_ofileflags[dfd]; + fdp->fd_ofileflags[dfd] = 0; + fdunused(fdp, dfd); + break; + } + FILEDESC_XUNLOCK(fdp); + *indxp = indx; + return (0); +} + +/* + * Scan all active processes and prisons to see if any of them have a current + * or root directory of `olddp'. If so, replace them with the new mount point. + */ +void +mountcheckdirs(struct vnode *olddp, struct vnode *newdp) +{ + struct filedesc *fdp; + struct prison *pr; + struct proc *p; + int nrele; + + if (vrefcnt(olddp) == 1) + return; + nrele = 0; + sx_slock(&allproc_lock); + FOREACH_PROC_IN_SYSTEM(p) { + fdp = fdhold(p); + if (fdp == NULL) + continue; + FILEDESC_XLOCK(fdp); + if (fdp->fd_cdir == olddp) { + vref(newdp); + fdp->fd_cdir = newdp; + nrele++; + } + if (fdp->fd_rdir == olddp) { + vref(newdp); + fdp->fd_rdir = newdp; + nrele++; + } + if (fdp->fd_jdir == olddp) { + vref(newdp); + fdp->fd_jdir = newdp; + nrele++; + } + FILEDESC_XUNLOCK(fdp); + fddrop(fdp); + } + sx_sunlock(&allproc_lock); + if (rootvnode == olddp) { + vref(newdp); + rootvnode = newdp; + nrele++; + } + mtx_lock(&prison0.pr_mtx); + if (prison0.pr_root == olddp) { + vref(newdp); + prison0.pr_root = newdp; + nrele++; + } + mtx_unlock(&prison0.pr_mtx); + sx_slock(&allprison_lock); + TAILQ_FOREACH(pr, &allprison, pr_list) { + mtx_lock(&pr->pr_mtx); + if (pr->pr_root == olddp) { + vref(newdp); + pr->pr_root = newdp; + nrele++; + } + mtx_unlock(&pr->pr_mtx); + } + sx_sunlock(&allprison_lock); + while (nrele--) + vrele(olddp); +} + +struct filedesc_to_leader * +filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader) +{ + struct filedesc_to_leader *fdtol; + + fdtol = malloc(sizeof(struct filedesc_to_leader), + M_FILEDESC_TO_LEADER, + M_WAITOK); + fdtol->fdl_refcount = 1; + fdtol->fdl_holdcount = 0; + fdtol->fdl_wakeup = 0; + fdtol->fdl_leader = leader; + if (old != NULL) { + FILEDESC_XLOCK(fdp); + fdtol->fdl_next = old->fdl_next; + fdtol->fdl_prev = old; + old->fdl_next = fdtol; + fdtol->fdl_next->fdl_prev = fdtol; + FILEDESC_XUNLOCK(fdp); + } else { + fdtol->fdl_next = fdtol; + fdtol->fdl_prev = fdtol; + } + return (fdtol); +} + +/* + * Get file structures globally. + */ +static int +sysctl_kern_file(SYSCTL_HANDLER_ARGS) +{ + struct xfile xf; + struct filedesc *fdp; + struct file *fp; + struct proc *p; + int error, n; + + error = sysctl_wire_old_buffer(req, 0); + if (error != 0) + return (error); + if (req->oldptr == NULL) { + n = 0; + sx_slock(&allproc_lock); + FOREACH_PROC_IN_SYSTEM(p) { + if (p->p_state == PRS_NEW) + continue; + fdp = fdhold(p); + if (fdp == NULL) + continue; + /* overestimates sparse tables. */ + if (fdp->fd_lastfile > 0) + n += fdp->fd_lastfile; + fddrop(fdp); + } + sx_sunlock(&allproc_lock); + return (SYSCTL_OUT(req, 0, n * sizeof(xf))); + } + error = 0; + bzero(&xf, sizeof(xf)); + xf.xf_size = sizeof(xf); + sx_slock(&allproc_lock); + FOREACH_PROC_IN_SYSTEM(p) { + PROC_LOCK(p); + if (p->p_state == PRS_NEW) { + PROC_UNLOCK(p); + continue; + } + if (p_cansee(req->td, p) != 0) { + PROC_UNLOCK(p); + continue; + } + xf.xf_pid = p->p_pid; + xf.xf_uid = p->p_ucred->cr_uid; + PROC_UNLOCK(p); + fdp = fdhold(p); + if (fdp == NULL) + continue; + FILEDESC_SLOCK(fdp); + for (n = 0; fdp->fd_refcnt > 0 && n < fdp->fd_nfiles; ++n) { + if ((fp = fdp->fd_ofiles[n]) == NULL) + continue; + xf.xf_fd = n; + xf.xf_file = fp; + xf.xf_data = fp->f_data; + xf.xf_vnode = fp->f_vnode; + xf.xf_type = fp->f_type; + xf.xf_count = fp->f_count; + xf.xf_msgcount = 0; + xf.xf_offset = foffset_get(fp); + xf.xf_flag = fp->f_flag; + error = SYSCTL_OUT(req, &xf, sizeof(xf)); + if (error) + break; + } + FILEDESC_SUNLOCK(fdp); + fddrop(fdp); + if (error) + break; + } + sx_sunlock(&allproc_lock); + return (error); +} + +SYSCTL_PROC(_kern, KERN_FILE, file, CTLTYPE_OPAQUE|CTLFLAG_RD, + 0, 0, sysctl_kern_file, "S,xfile", "Entire file table"); + +#ifdef KINFO_OFILE_SIZE +CTASSERT(sizeof(struct kinfo_ofile) == KINFO_OFILE_SIZE); +#endif + +#ifdef COMPAT_FREEBSD7 +static int +export_vnode_for_osysctl(struct vnode *vp, int type, + struct kinfo_ofile *kif, struct filedesc *fdp, struct sysctl_req *req) +{ + int error; + char *fullpath, *freepath; + + bzero(kif, sizeof(*kif)); + kif->kf_structsize = sizeof(*kif); + + vref(vp); + kif->kf_fd = type; + kif->kf_type = KF_TYPE_VNODE; + /* This function only handles directories. */ + if (vp->v_type != VDIR) { + vrele(vp); + return (ENOTDIR); + } + kif->kf_vnode_type = KF_VTYPE_VDIR; + + /* + * This is not a true file descriptor, so we set a bogus refcount + * and offset to indicate these fields should be ignored. + */ + kif->kf_ref_count = -1; + kif->kf_offset = -1; + + freepath = NULL; + fullpath = "-"; + FILEDESC_SUNLOCK(fdp); + vn_fullpath(curthread, vp, &fullpath, &freepath); + vrele(vp); + strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); + if (freepath != NULL) + free(freepath, M_TEMP); + error = SYSCTL_OUT(req, kif, sizeof(*kif)); + FILEDESC_SLOCK(fdp); + return (error); +} + +/* + * Get per-process file descriptors for use by procstat(1), et al. + */ +static int +sysctl_kern_proc_ofiledesc(SYSCTL_HANDLER_ARGS) +{ + char *fullpath, *freepath; + struct kinfo_ofile *kif; + struct filedesc *fdp; + int error, i, *name; + struct shmfd *shmfd; + struct socket *so; + struct vnode *vp; + struct file *fp; + struct proc *p; + struct tty *tp; + + name = (int *)arg1; + if ((p = pfind((pid_t)name[0])) == NULL) + return (ESRCH); + if ((error = p_candebug(curthread, p))) { + PROC_UNLOCK(p); + return (error); + } + fdp = fdhold(p); + PROC_UNLOCK(p); + if (fdp == NULL) + return (ENOENT); + kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); + FILEDESC_SLOCK(fdp); + if (fdp->fd_cdir != NULL) + export_vnode_for_osysctl(fdp->fd_cdir, KF_FD_TYPE_CWD, kif, + fdp, req); + if (fdp->fd_rdir != NULL) + export_vnode_for_osysctl(fdp->fd_rdir, KF_FD_TYPE_ROOT, kif, + fdp, req); + if (fdp->fd_jdir != NULL) + export_vnode_for_osysctl(fdp->fd_jdir, KF_FD_TYPE_JAIL, kif, + fdp, req); + for (i = 0; i < fdp->fd_nfiles; i++) { + if ((fp = fdp->fd_ofiles[i]) == NULL) + continue; + bzero(kif, sizeof(*kif)); + kif->kf_structsize = sizeof(*kif); + vp = NULL; + so = NULL; + tp = NULL; + shmfd = NULL; + kif->kf_fd = i; + +#ifdef CAPABILITIES + /* + * When reporting a capability, most fields will be from the + * underlying object, but do mark as a capability. With + * ofiledesc, we don't have a field to export the cap_rights_t, + * but we do with the new filedesc. + */ + if (fp->f_type == DTYPE_CAPABILITY) { + kif->kf_flags |= KF_FLAG_CAPABILITY; + (void)cap_funwrap(fp, 0, &fp); + } +#else + KASSERT(fp->f_type != DTYPE_CAPABILITY, + ("sysctl_kern_proc_ofiledesc: saw capability")); +#endif + switch (fp->f_type) { + case DTYPE_VNODE: + kif->kf_type = KF_TYPE_VNODE; + vp = fp->f_vnode; + break; + + case DTYPE_SOCKET: + kif->kf_type = KF_TYPE_SOCKET; + so = fp->f_data; + break; + + case DTYPE_PIPE: + kif->kf_type = KF_TYPE_PIPE; + break; + + case DTYPE_FIFO: + kif->kf_type = KF_TYPE_FIFO; + vp = fp->f_vnode; + break; + + case DTYPE_KQUEUE: + kif->kf_type = KF_TYPE_KQUEUE; + break; + + case DTYPE_CRYPTO: + kif->kf_type = KF_TYPE_CRYPTO; + break; + + case DTYPE_MQUEUE: + kif->kf_type = KF_TYPE_MQUEUE; + break; + + case DTYPE_SHM: + kif->kf_type = KF_TYPE_SHM; + shmfd = fp->f_data; + break; + + case DTYPE_SEM: + kif->kf_type = KF_TYPE_SEM; + break; + + case DTYPE_PTS: + kif->kf_type = KF_TYPE_PTS; + tp = fp->f_data; + break; + +#ifdef PROCDESC + case DTYPE_PROCDESC: + kif->kf_type = KF_TYPE_PROCDESC; + break; +#endif + + default: + kif->kf_type = KF_TYPE_UNKNOWN; + break; + } + kif->kf_ref_count = fp->f_count; + if (fp->f_flag & FREAD) + kif->kf_flags |= KF_FLAG_READ; + if (fp->f_flag & FWRITE) + kif->kf_flags |= KF_FLAG_WRITE; + if (fp->f_flag & FAPPEND) + kif->kf_flags |= KF_FLAG_APPEND; + if (fp->f_flag & FASYNC) + kif->kf_flags |= KF_FLAG_ASYNC; + if (fp->f_flag & FFSYNC) + kif->kf_flags |= KF_FLAG_FSYNC; + if (fp->f_flag & FNONBLOCK) + kif->kf_flags |= KF_FLAG_NONBLOCK; + if (fp->f_flag & O_DIRECT) + kif->kf_flags |= KF_FLAG_DIRECT; + if (fp->f_flag & FHASLOCK) + kif->kf_flags |= KF_FLAG_HASLOCK; + kif->kf_offset = foffset_get(fp); + if (vp != NULL) { + vref(vp); + switch (vp->v_type) { + case VNON: + kif->kf_vnode_type = KF_VTYPE_VNON; + break; + case VREG: + kif->kf_vnode_type = KF_VTYPE_VREG; + break; + case VDIR: + kif->kf_vnode_type = KF_VTYPE_VDIR; + break; + case VBLK: + kif->kf_vnode_type = KF_VTYPE_VBLK; + break; + case VCHR: + kif->kf_vnode_type = KF_VTYPE_VCHR; + break; + case VLNK: + kif->kf_vnode_type = KF_VTYPE_VLNK; + break; + case VSOCK: + kif->kf_vnode_type = KF_VTYPE_VSOCK; + break; + case VFIFO: + kif->kf_vnode_type = KF_VTYPE_VFIFO; + break; + case VBAD: + kif->kf_vnode_type = KF_VTYPE_VBAD; + break; + default: + kif->kf_vnode_type = KF_VTYPE_UNKNOWN; + break; + } + /* + * It is OK to drop the filedesc lock here as we will + * re-validate and re-evaluate its properties when + * the loop continues. + */ + freepath = NULL; + fullpath = "-"; + FILEDESC_SUNLOCK(fdp); + vn_fullpath(curthread, vp, &fullpath, &freepath); + vrele(vp); + strlcpy(kif->kf_path, fullpath, + sizeof(kif->kf_path)); + if (freepath != NULL) + free(freepath, M_TEMP); + FILEDESC_SLOCK(fdp); + } + if (so != NULL) { + struct sockaddr *sa; + + if (so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa) + == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { + bcopy(sa, &kif->kf_sa_local, sa->sa_len); + free(sa, M_SONAME); + } + if (so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa) + == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { + bcopy(sa, &kif->kf_sa_peer, sa->sa_len); + free(sa, M_SONAME); + } + kif->kf_sock_domain = + so->so_proto->pr_domain->dom_family; + kif->kf_sock_type = so->so_type; + kif->kf_sock_protocol = so->so_proto->pr_protocol; + } + if (tp != NULL) { + strlcpy(kif->kf_path, tty_devname(tp), + sizeof(kif->kf_path)); + } + if (shmfd != NULL) + shm_path(shmfd, kif->kf_path, sizeof(kif->kf_path)); + error = SYSCTL_OUT(req, kif, sizeof(*kif)); + if (error) + break; + } + FILEDESC_SUNLOCK(fdp); + fddrop(fdp); + free(kif, M_TEMP); + return (0); +} + +static SYSCTL_NODE(_kern_proc, KERN_PROC_OFILEDESC, ofiledesc, CTLFLAG_RD, + sysctl_kern_proc_ofiledesc, "Process ofiledesc entries"); +#endif /* COMPAT_FREEBSD7 */ + +#ifdef KINFO_FILE_SIZE +CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); +#endif + +static int +export_fd_for_sysctl(void *data, int type, int fd, int fflags, int refcnt, + int64_t offset, int fd_is_cap, cap_rights_t fd_cap_rights, + struct kinfo_file *kif, struct sysctl_req *req) +{ + struct { + int fflag; + int kf_fflag; + } fflags_table[] = { + { FAPPEND, KF_FLAG_APPEND }, + { FASYNC, KF_FLAG_ASYNC }, + { FFSYNC, KF_FLAG_FSYNC }, + { FHASLOCK, KF_FLAG_HASLOCK }, + { FNONBLOCK, KF_FLAG_NONBLOCK }, + { FREAD, KF_FLAG_READ }, + { FWRITE, KF_FLAG_WRITE }, + { O_CREAT, KF_FLAG_CREAT }, + { O_DIRECT, KF_FLAG_DIRECT }, + { O_EXCL, KF_FLAG_EXCL }, + { O_EXEC, KF_FLAG_EXEC }, + { O_EXLOCK, KF_FLAG_EXLOCK }, + { O_NOFOLLOW, KF_FLAG_NOFOLLOW }, + { O_SHLOCK, KF_FLAG_SHLOCK }, + { O_TRUNC, KF_FLAG_TRUNC } + }; +#define NFFLAGS (sizeof(fflags_table) / sizeof(*fflags_table)) + struct vnode *vp; + int error; + unsigned int i; + + bzero(kif, sizeof(*kif)); + switch (type) { + case KF_TYPE_FIFO: + case KF_TYPE_VNODE: + vp = (struct vnode *)data; + error = fill_vnode_info(vp, kif); + vrele(vp); + break; + case KF_TYPE_SOCKET: + error = fill_socket_info((struct socket *)data, kif); + break; + case KF_TYPE_PIPE: + error = fill_pipe_info((struct pipe *)data, kif); + break; + case KF_TYPE_PTS: + error = fill_pts_info((struct tty *)data, kif); + break; + case KF_TYPE_PROCDESC: + error = fill_procdesc_info((struct procdesc *)data, kif); + break; + case KF_TYPE_SHM: + error = fill_shm_info((struct file *)data, kif); + break; + default: + error = 0; + } + if (error == 0) + kif->kf_status |= KF_ATTR_VALID; + + /* + * Translate file access flags. + */ + for (i = 0; i < NFFLAGS; i++) + if (fflags & fflags_table[i].fflag) + kif->kf_flags |= fflags_table[i].kf_fflag; + if (fd_is_cap) + kif->kf_flags |= KF_FLAG_CAPABILITY; + if (fd_is_cap) + kif->kf_cap_rights = fd_cap_rights; + kif->kf_fd = fd; + kif->kf_type = type; + kif->kf_ref_count = refcnt; + kif->kf_offset = offset; + /* Pack record size down */ + kif->kf_structsize = offsetof(struct kinfo_file, kf_path) + + strlen(kif->kf_path) + 1; + kif->kf_structsize = roundup(kif->kf_structsize, sizeof(uint64_t)); + error = SYSCTL_OUT(req, kif, kif->kf_structsize); + return (error); +} + +/* + * Get per-process file descriptors for use by procstat(1), et al. + */ +static int +sysctl_kern_proc_filedesc(SYSCTL_HANDLER_ARGS) +{ + struct file *fp; + struct filedesc *fdp; + struct kinfo_file *kif; + struct proc *p; + struct vnode *cttyvp, *textvp, *tracevp; + size_t oldidx; + int64_t offset; + void *data; + int error, i, *name; + int fd_is_cap, type, refcnt, fflags; + cap_rights_t fd_cap_rights; + + name = (int *)arg1; + if ((p = pfind((pid_t)name[0])) == NULL) + return (ESRCH); + if ((error = p_candebug(curthread, p))) { + PROC_UNLOCK(p); + return (error); + } + /* ktrace vnode */ + tracevp = p->p_tracevp; + if (tracevp != NULL) + vref(tracevp); + /* text vnode */ + textvp = p->p_textvp; + if (textvp != NULL) + vref(textvp); + /* Controlling tty. */ + cttyvp = NULL; + if (p->p_pgrp != NULL && p->p_pgrp->pg_session != NULL) { + cttyvp = p->p_pgrp->pg_session->s_ttyvp; + if (cttyvp != NULL) + vref(cttyvp); + } + fdp = fdhold(p); + PROC_UNLOCK(p); + kif = malloc(sizeof(*kif), M_TEMP, M_WAITOK); + if (tracevp != NULL) + export_fd_for_sysctl(tracevp, KF_TYPE_VNODE, KF_FD_TYPE_TRACE, + FREAD | FWRITE, -1, -1, 0, 0, kif, req); + if (textvp != NULL) + export_fd_for_sysctl(textvp, KF_TYPE_VNODE, KF_FD_TYPE_TEXT, + FREAD, -1, -1, 0, 0, kif, req); + if (cttyvp != NULL) + export_fd_for_sysctl(cttyvp, KF_TYPE_VNODE, KF_FD_TYPE_CTTY, + FREAD | FWRITE, -1, -1, 0, 0, kif, req); + if (fdp == NULL) + goto fail; + FILEDESC_SLOCK(fdp); + /* working directory */ + if (fdp->fd_cdir != NULL) { + vref(fdp->fd_cdir); + data = fdp->fd_cdir; + FILEDESC_SUNLOCK(fdp); + export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_CWD, + FREAD, -1, -1, 0, 0, kif, req); + FILEDESC_SLOCK(fdp); + } + /* root directory */ + if (fdp->fd_rdir != NULL) { + vref(fdp->fd_rdir); + data = fdp->fd_rdir; + FILEDESC_SUNLOCK(fdp); + export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_ROOT, + FREAD, -1, -1, 0, 0, kif, req); + FILEDESC_SLOCK(fdp); + } + /* jail directory */ + if (fdp->fd_jdir != NULL) { + vref(fdp->fd_jdir); + data = fdp->fd_jdir; + FILEDESC_SUNLOCK(fdp); + export_fd_for_sysctl(data, KF_TYPE_VNODE, KF_FD_TYPE_JAIL, + FREAD, -1, -1, 0, 0, kif, req); + FILEDESC_SLOCK(fdp); + } + for (i = 0; i < fdp->fd_nfiles; i++) { + if ((fp = fdp->fd_ofiles[i]) == NULL) + continue; + data = NULL; + fd_is_cap = 0; + fd_cap_rights = 0; + +#ifdef CAPABILITIES + /* + * When reporting a capability, most fields will be from the + * underlying object, but do mark as a capability and export + * the capability rights mask. + */ + if (fp->f_type == DTYPE_CAPABILITY) { + fd_is_cap = 1; + fd_cap_rights = cap_rights(fp); + (void)cap_funwrap(fp, 0, &fp); + } +#else /* !CAPABILITIES */ + KASSERT(fp->f_type != DTYPE_CAPABILITY, + ("sysctl_kern_proc_filedesc: saw capability")); +#endif + switch (fp->f_type) { + case DTYPE_VNODE: + type = KF_TYPE_VNODE; + vref(fp->f_vnode); + data = fp->f_vnode; + break; + + case DTYPE_SOCKET: + type = KF_TYPE_SOCKET; + data = fp->f_data; + break; + + case DTYPE_PIPE: + type = KF_TYPE_PIPE; + data = fp->f_data; + break; + + case DTYPE_FIFO: + type = KF_TYPE_FIFO; + vref(fp->f_vnode); + data = fp->f_vnode; + break; + + case DTYPE_KQUEUE: + type = KF_TYPE_KQUEUE; + break; + + case DTYPE_CRYPTO: + type = KF_TYPE_CRYPTO; + break; + + case DTYPE_MQUEUE: + type = KF_TYPE_MQUEUE; + break; + + case DTYPE_SHM: + type = KF_TYPE_SHM; + data = fp; + break; + + case DTYPE_SEM: + type = KF_TYPE_SEM; + break; + + case DTYPE_PTS: + type = KF_TYPE_PTS; + data = fp->f_data; + break; + +#ifdef PROCDESC + case DTYPE_PROCDESC: + type = KF_TYPE_PROCDESC; + data = fp->f_data; + break; +#endif + + default: + type = KF_TYPE_UNKNOWN; + break; + } + refcnt = fp->f_count; + fflags = fp->f_flag; + offset = foffset_get(fp); + + /* + * Create sysctl entry. + * It is OK to drop the filedesc lock here as we will + * re-validate and re-evaluate its properties when + * the loop continues. + */ + oldidx = req->oldidx; + if (type == KF_TYPE_VNODE || type == KF_TYPE_FIFO) + FILEDESC_SUNLOCK(fdp); + error = export_fd_for_sysctl(data, type, i, fflags, refcnt, + offset, fd_is_cap, fd_cap_rights, kif, req); + if (type == KF_TYPE_VNODE || type == KF_TYPE_FIFO) + FILEDESC_SLOCK(fdp); + if (error) { + if (error == ENOMEM) { + /* + * The hack to keep the ABI of sysctl + * kern.proc.filedesc intact, but not + * to account a partially copied + * kinfo_file into the oldidx. + */ + req->oldidx = oldidx; + error = 0; + } + break; + } + } + FILEDESC_SUNLOCK(fdp); +fail: + if (fdp != NULL) + fddrop(fdp); + free(kif, M_TEMP); + return (error); +} + +int +vntype_to_kinfo(int vtype) +{ + struct { + int vtype; + int kf_vtype; + } vtypes_table[] = { + { VBAD, KF_VTYPE_VBAD }, + { VBLK, KF_VTYPE_VBLK }, + { VCHR, KF_VTYPE_VCHR }, + { VDIR, KF_VTYPE_VDIR }, + { VFIFO, KF_VTYPE_VFIFO }, + { VLNK, KF_VTYPE_VLNK }, + { VNON, KF_VTYPE_VNON }, + { VREG, KF_VTYPE_VREG }, + { VSOCK, KF_VTYPE_VSOCK } + }; +#define NVTYPES (sizeof(vtypes_table) / sizeof(*vtypes_table)) + unsigned int i; + + /* + * Perform vtype translation. + */ + for (i = 0; i < NVTYPES; i++) + if (vtypes_table[i].vtype == vtype) + break; + if (i < NVTYPES) + return (vtypes_table[i].kf_vtype); + + return (KF_VTYPE_UNKNOWN); +} + +static int +fill_vnode_info(struct vnode *vp, struct kinfo_file *kif) +{ + struct vattr va; + char *fullpath, *freepath; + int error; + + if (vp == NULL) + return (1); + kif->kf_vnode_type = vntype_to_kinfo(vp->v_type); + freepath = NULL; + fullpath = "-"; + error = vn_fullpath(curthread, vp, &fullpath, &freepath); + if (error == 0) { + strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path)); + } + if (freepath != NULL) + free(freepath, M_TEMP); + + /* + * Retrieve vnode attributes. + */ + va.va_fsid = VNOVAL; + va.va_rdev = NODEV; + vn_lock(vp, LK_SHARED | LK_RETRY); + error = VOP_GETATTR(vp, &va, curthread->td_ucred); + VOP_UNLOCK(vp, 0); + if (error != 0) + return (error); + if (va.va_fsid != VNOVAL) + kif->kf_un.kf_file.kf_file_fsid = va.va_fsid; + else + kif->kf_un.kf_file.kf_file_fsid = + vp->v_mount->mnt_stat.f_fsid.val[0]; + kif->kf_un.kf_file.kf_file_fileid = va.va_fileid; + kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode); + kif->kf_un.kf_file.kf_file_size = va.va_size; + kif->kf_un.kf_file.kf_file_rdev = va.va_rdev; + return (0); +} + +static int +fill_socket_info(struct socket *so, struct kinfo_file *kif) +{ + struct sockaddr *sa; + struct inpcb *inpcb; + struct unpcb *unpcb; + int error; + + if (so == NULL) + return (1); + kif->kf_sock_domain = so->so_proto->pr_domain->dom_family; + kif->kf_sock_type = so->so_type; + kif->kf_sock_protocol = so->so_proto->pr_protocol; + kif->kf_un.kf_sock.kf_sock_pcb = (uintptr_t)so->so_pcb; + switch(kif->kf_sock_domain) { + case AF_INET: + case AF_INET6: + if (kif->kf_sock_protocol == IPPROTO_TCP) { + if (so->so_pcb != NULL) { + inpcb = (struct inpcb *)(so->so_pcb); + kif->kf_un.kf_sock.kf_sock_inpcb = + (uintptr_t)inpcb->inp_ppcb; + } + } + break; + case AF_UNIX: + if (so->so_pcb != NULL) { + unpcb = (struct unpcb *)(so->so_pcb); + if (unpcb->unp_conn) { + kif->kf_un.kf_sock.kf_sock_unpconn = + (uintptr_t)unpcb->unp_conn; + kif->kf_un.kf_sock.kf_sock_rcv_sb_state = + so->so_rcv.sb_state; + kif->kf_un.kf_sock.kf_sock_snd_sb_state = + so->so_snd.sb_state; + } + } + break; + } + error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa); + if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_local)) { + bcopy(sa, &kif->kf_sa_local, sa->sa_len); + free(sa, M_SONAME); + } + error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa); + if (error == 0 && sa->sa_len <= sizeof(kif->kf_sa_peer)) { + bcopy(sa, &kif->kf_sa_peer, sa->sa_len); + free(sa, M_SONAME); + } + strncpy(kif->kf_path, so->so_proto->pr_domain->dom_name, + sizeof(kif->kf_path)); + return (0); +} + +static int +fill_pts_info(struct tty *tp, struct kinfo_file *kif) +{ + + if (tp == NULL) + return (1); + kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp); + strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path)); + return (0); +} + +static int +fill_pipe_info(struct pipe *pi, struct kinfo_file *kif) +{ + + if (pi == NULL) + return (1); + kif->kf_un.kf_pipe.kf_pipe_addr = (uintptr_t)pi; + kif->kf_un.kf_pipe.kf_pipe_peer = (uintptr_t)pi->pipe_peer; + kif->kf_un.kf_pipe.kf_pipe_buffer_cnt = pi->pipe_buffer.cnt; + return (0); +} + +static int +fill_procdesc_info(struct procdesc *pdp, struct kinfo_file *kif) +{ + + if (pdp == NULL) + return (1); + kif->kf_un.kf_proc.kf_pid = pdp->pd_pid; + return (0); +} + +static int +fill_shm_info(struct file *fp, struct kinfo_file *kif) +{ + struct thread *td; + struct stat sb; + + td = curthread; + if (fp->f_data == NULL) + return (1); + if (fo_stat(fp, &sb, td->td_ucred, td) != 0) + return (1); + shm_path(fp->f_data, kif->kf_path, sizeof(kif->kf_path)); + kif->kf_un.kf_file.kf_file_mode = sb.st_mode; + kif->kf_un.kf_file.kf_file_size = sb.st_size; + return (0); +} + +static SYSCTL_NODE(_kern_proc, KERN_PROC_FILEDESC, filedesc, CTLFLAG_RD, + sysctl_kern_proc_filedesc, "Process filedesc entries"); + +#ifdef DDB +/* + * For the purposes of debugging, generate a human-readable string for the + * file type. + */ +static const char * +file_type_to_name(short type) +{ + + switch (type) { + case 0: + return ("zero"); + case DTYPE_VNODE: + return ("vnod"); + case DTYPE_SOCKET: + return ("sock"); + case DTYPE_PIPE: + return ("pipe"); + case DTYPE_FIFO: + return ("fifo"); + case DTYPE_KQUEUE: + return ("kque"); + case DTYPE_CRYPTO: + return ("crpt"); + case DTYPE_MQUEUE: + return ("mque"); + case DTYPE_SHM: + return ("shm"); + case DTYPE_SEM: + return ("ksem"); + default: + return ("unkn"); + } +} + +/* + * For the purposes of debugging, identify a process (if any, perhaps one of + * many) that references the passed file in its file descriptor array. Return + * NULL if none. + */ +static struct proc * +file_to_first_proc(struct file *fp) +{ + struct filedesc *fdp; + struct proc *p; + int n; + + FOREACH_PROC_IN_SYSTEM(p) { + if (p->p_state == PRS_NEW) + continue; + fdp = p->p_fd; + if (fdp == NULL) + continue; + for (n = 0; n < fdp->fd_nfiles; n++) { + if (fp == fdp->fd_ofiles[n]) + return (p); + } + } + return (NULL); +} + +static void +db_print_file(struct file *fp, int header) +{ + struct proc *p; + + if (header) + db_printf("%8s %4s %8s %8s %4s %5s %6s %8s %5s %12s\n", + "File", "Type", "Data", "Flag", "GCFl", "Count", + "MCount", "Vnode", "FPID", "FCmd"); + p = file_to_first_proc(fp); + db_printf("%8p %4s %8p %08x %04x %5d %6d %8p %5d %12s\n", fp, + file_type_to_name(fp->f_type), fp->f_data, fp->f_flag, + 0, fp->f_count, 0, fp->f_vnode, + p != NULL ? p->p_pid : -1, p != NULL ? p->p_comm : "-"); +} + +DB_SHOW_COMMAND(file, db_show_file) +{ + struct file *fp; + + if (!have_addr) { + db_printf("usage: show file <addr>\n"); + return; + } + fp = (struct file *)addr; + db_print_file(fp, 1); +} + +DB_SHOW_COMMAND(files, db_show_files) +{ + struct filedesc *fdp; + struct file *fp; + struct proc *p; + int header; + int n; + + header = 1; + FOREACH_PROC_IN_SYSTEM(p) { + if (p->p_state == PRS_NEW) + continue; + if ((fdp = p->p_fd) == NULL) + continue; + for (n = 0; n < fdp->fd_nfiles; ++n) { + if ((fp = fdp->fd_ofiles[n]) == NULL) + continue; + db_print_file(fp, header); + header = 0; + } + } +} +#endif + +SYSCTL_INT(_kern, KERN_MAXFILESPERPROC, maxfilesperproc, CTLFLAG_RW, + &maxfilesperproc, 0, "Maximum files allowed open per process"); + +SYSCTL_INT(_kern, KERN_MAXFILES, maxfiles, CTLFLAG_RW, + &maxfiles, 0, "Maximum number of files"); + +SYSCTL_INT(_kern, OID_AUTO, openfiles, CTLFLAG_RD, + __DEVOLATILE(int *, &openfiles), 0, "System-wide number of open files"); + +/* ARGSUSED*/ +static void +filelistinit(void *dummy) +{ + + file_zone = uma_zcreate("Files", sizeof(struct file), NULL, NULL, + NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); + mtx_init(&sigio_lock, "sigio lock", NULL, MTX_DEF); + mtx_init(&fdesc_mtx, "fdesc", NULL, MTX_DEF); +} +SYSINIT(select, SI_SUB_LOCK, SI_ORDER_FIRST, filelistinit, NULL); + +/*-------------------------------------------------------------------*/ + +static int +badfo_readwrite(struct file *fp, struct uio *uio, struct ucred *active_cred, + int flags, struct thread *td) +{ + + return (EBADF); +} + +static int +badfo_truncate(struct file *fp, off_t length, struct ucred *active_cred, + struct thread *td) +{ + + return (EINVAL); +} + +static int +badfo_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred, + struct thread *td) +{ + + return (EBADF); +} + +static int +badfo_poll(struct file *fp, int events, struct ucred *active_cred, + struct thread *td) +{ + + return (0); +} + +static int +badfo_kqfilter(struct file *fp, struct knote *kn) +{ + + return (EBADF); +} + +static int +badfo_stat(struct file *fp, struct stat *sb, struct ucred *active_cred, + struct thread *td) +{ + + return (EBADF); +} + +static int +badfo_close(struct file *fp, struct thread *td) +{ + + return (EBADF); +} + +static int +badfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, + struct thread *td) +{ + + return (EBADF); +} + +static int +badfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, + struct thread *td) +{ + + return (EBADF); +} + +struct fileops badfileops = { + .fo_read = badfo_readwrite, + .fo_write = badfo_readwrite, + .fo_truncate = badfo_truncate, + .fo_ioctl = badfo_ioctl, + .fo_poll = badfo_poll, + .fo_kqfilter = badfo_kqfilter, + .fo_stat = badfo_stat, + .fo_close = badfo_close, + .fo_chmod = badfo_chmod, + .fo_chown = badfo_chown, +}; + +int +invfo_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, + struct thread *td) +{ + + return (EINVAL); +} + +int +invfo_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, + struct thread *td) +{ + + return (EINVAL); +} + +/*-------------------------------------------------------------------*/ + +/* + * File Descriptor pseudo-device driver (/dev/fd/). + * + * Opening minor device N dup()s the file (if any) connected to file + * descriptor N belonging to the calling process. Note that this driver + * consists of only the ``open()'' routine, because all subsequent + * references to this file will be direct to the other driver. + * + * XXX: we could give this one a cloning event handler if necessary. + */ + +/* ARGSUSED */ +static int +fdopen(struct cdev *dev, int mode, int type, struct thread *td) +{ + + /* + * XXX Kludge: set curthread->td_dupfd to contain the value of the + * the file descriptor being sought for duplication. The error + * return ensures that the vnode for this device will be released + * by vn_open. Open will detect this special error and take the + * actions in dupfdopen below. Other callers of vn_open or VOP_OPEN + * will simply report the error. + */ + td->td_dupfd = dev2unit(dev); + return (ENODEV); +} + +static struct cdevsw fildesc_cdevsw = { + .d_version = D_VERSION, + .d_open = fdopen, + .d_name = "FD", +}; + +static void +fildesc_drvinit(void *unused) +{ + struct cdev *dev; + + dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 0, NULL, + UID_ROOT, GID_WHEEL, 0666, "fd/0"); + make_dev_alias(dev, "stdin"); + dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 1, NULL, + UID_ROOT, GID_WHEEL, 0666, "fd/1"); + make_dev_alias(dev, "stdout"); + dev = make_dev_credf(MAKEDEV_ETERNAL, &fildesc_cdevsw, 2, NULL, + UID_ROOT, GID_WHEEL, 0666, "fd/2"); + make_dev_alias(dev, "stderr"); +} + +SYSINIT(fildescdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE, fildesc_drvinit, NULL); |
