/*- * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * 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. * * @(#)filedesc.h 8.1 (Berkeley) 6/2/93 * $FreeBSD$ */ #ifndef _SYS_FILEDESC_H_ #define _SYS_FILEDESC_H_ #include #include #include #include #include #include #include #include struct filecaps { cap_rights_t fc_rights; /* per-descriptor capability rights */ u_long *fc_ioctls; /* per-descriptor allowed ioctls */ int16_t fc_nioctls; /* fc_ioctls array size */ uint32_t fc_fcntls; /* per-descriptor allowed fcntls */ }; struct filedescent { struct file *fde_file; /* file structure for open file */ struct filecaps fde_caps; /* per-descriptor rights */ uint8_t fde_flags; /* per-process open file flags */ seq_t fde_seq; /* keep file and caps in sync */ }; #define fde_rights fde_caps.fc_rights #define fde_fcntls fde_caps.fc_fcntls #define fde_ioctls fde_caps.fc_ioctls #define fde_nioctls fde_caps.fc_nioctls #define fde_change_size (offsetof(struct filedescent, fde_seq)) struct fdescenttbl { int fdt_nfiles; /* number of open files allocated */ struct filedescent fdt_ofiles[0]; /* open files */ }; #define fd_seq(fdt, fd) (&(fdt)->fdt_ofiles[(fd)].fde_seq) /* * This structure is used for the management of descriptors. It may be * shared by multiple processes. */ #define NDSLOTTYPE u_long struct filedesc { struct fdescenttbl *fd_files; /* open files table */ struct vnode *fd_cdir; /* current directory */ struct vnode *fd_rdir; /* root directory */ struct vnode *fd_jdir; /* jail root directory */ NDSLOTTYPE *fd_map; /* bitmap of free fds */ int fd_lastfile; /* high-water mark of fd_ofiles */ int fd_freefile; /* approx. next free file */ u_short fd_cmask; /* mask for file creation */ int fd_refcnt; /* thread reference count */ int fd_holdcnt; /* hold count on structure + mutex */ struct sx fd_sx; /* protects members of this struct */ struct kqlist fd_kqlist; /* list of kqueues on this filedesc */ int fd_holdleaderscount; /* block fdfree() for shared close() */ int fd_holdleaderswakeup; /* fdfree() needs wakeup */ }; /* * Structure to keep track of (process leader, struct fildedesc) tuples. * Each process has a pointer to such a structure when detailed tracking * is needed, e.g., when rfork(RFPROC | RFMEM) causes a file descriptor * table to be shared by processes having different "p_leader" pointers * and thus distinct POSIX style locks. * * fdl_refcount and fdl_holdcount are protected by struct filedesc mtx. */ struct filedesc_to_leader { int fdl_refcount; /* references from struct proc */ int fdl_holdcount; /* temporary hold during closef */ int fdl_wakeup; /* fdfree() waits on closef() */ struct proc *fdl_leader; /* owner of POSIX locks */ /* Circular list: */ struct filedesc_to_leader *fdl_prev; struct filedesc_to_leader *fdl_next; }; #define fd_nfiles fd_files->fdt_nfiles #define fd_ofiles fd_files->fdt_ofiles /* * Per-process open flags. */ #define UF_EXCLOSE 0x01 /* auto-close on exec */ #ifdef _KERNEL /* Lock a file descriptor table. */ #define FILEDESC_LOCK_INIT(fdp) sx_init(&(fdp)->fd_sx, "filedesc structure") #define FILEDESC_LOCK_DESTROY(fdp) sx_destroy(&(fdp)->fd_sx) #define FILEDESC_LOCK(fdp) (&(fdp)->fd_sx) #define FILEDESC_XLOCK(fdp) sx_xlock(&(fdp)->fd_sx) #define FILEDESC_XUNLOCK(fdp) sx_xunlock(&(fdp)->fd_sx) #define FILEDESC_SLOCK(fdp) sx_slock(&(fdp)->fd_sx) #define FILEDESC_SUNLOCK(fdp) sx_sunlock(&(fdp)->fd_sx) #define FILEDESC_LOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_LOCKED | \ SX_NOTRECURSED) #define FILEDESC_XLOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_XLOCKED | \ SX_NOTRECURSED) #define FILEDESC_UNLOCK_ASSERT(fdp) sx_assert(&(fdp)->fd_sx, SX_UNLOCKED) /* Operation types for kern_dup(). */ enum { FDDUP_NORMAL, /* dup() behavior. */ FDDUP_FCNTL, /* fcntl()-style errors. */ FDDUP_FIXED, /* Force fixed allocation. */ FDDUP_MUSTREPLACE, /* Target must exist. */ FDDUP_LASTMODE, }; /* Flags for kern_dup(). */ #define FDDUP_FLAG_CLOEXEC 0x1 /* Atomically set UF_EXCLOSE. */ /* For backward compatibility. */ #define falloc(td, resultfp, resultfd, flags) \ falloc_caps(td, resultfp, resultfd, flags, NULL) struct thread; void filecaps_init(struct filecaps *fcaps); int filecaps_copy(const struct filecaps *src, struct filecaps *dst, bool locked); void filecaps_move(struct filecaps *src, struct filecaps *dst); void filecaps_free(struct filecaps *fcaps); int closef(struct file *fp, struct thread *td); int dupfdopen(struct thread *td, struct filedesc *fdp, int dfd, int mode, int openerror, int *indxp); int falloc_caps(struct thread *td, struct file **resultfp, int *resultfd, int flags, struct filecaps *fcaps); int falloc_noinstall(struct thread *td, struct file **resultfp); void _finstall(struct filedesc *fdp, struct file *fp, int fd, int flags, struct filecaps *fcaps); int finstall(struct thread *td, struct file *fp, int *resultfd, int flags, struct filecaps *fcaps); int fdalloc(struct thread *td, int minfd, int *result); int fdallocn(struct thread *td, int minfd, int *fds, int n); int fdcheckstd(struct thread *td); void fdclose(struct thread *td, struct file *fp, int idx); void fdcloseexec(struct thread *td); void fdsetugidsafety(struct thread *td); struct filedesc *fdcopy(struct filedesc *fdp); int fdcopy_remapped(struct filedesc *fdp, const int *fds, size_t nfds, struct filedesc **newfdp); void fdinstall_remapped(struct thread *td, struct filedesc *fdp); void fdunshare(struct thread *td); void fdescfree(struct thread *td); void fdescfree_remapped(struct filedesc *fdp); struct filedesc *fdinit(struct filedesc *fdp, bool prepfiles); struct filedesc *fdshare(struct filedesc *fdp); struct filedesc_to_leader * filedesc_to_leader_alloc(struct filedesc_to_leader *old, struct filedesc *fdp, struct proc *leader); int getvnode(struct thread *td, int fd, cap_rights_t *rightsp, struct file **fpp); void mountcheckdirs(struct vnode *olddp, struct vnode *newdp); int fget_cap_locked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, struct file **fpp, struct filecaps *havecapsp); int fget_cap(struct thread *td, int fd, cap_rights_t *needrightsp, struct file **fpp, struct filecaps *havecapsp); /* Return a referenced file from an unlocked descriptor. */ int fget_unlocked(struct filedesc *fdp, int fd, cap_rights_t *needrightsp, struct file **fpp, seq_t *seqp); /* Requires a FILEDESC_{S,X}LOCK held and returns without a ref. */ static __inline struct file * fget_locked(struct filedesc *fdp, int fd) { FILEDESC_LOCK_ASSERT(fdp); if (fd < 0 || fd > fdp->fd_lastfile) return (NULL); return (fdp->fd_ofiles[fd].fde_file); } static __inline struct filedescent * fdeget_locked(struct filedesc *fdp, int fd) { struct filedescent *fde; FILEDESC_LOCK_ASSERT(fdp); if (fd < 0 || fd > fdp->fd_lastfile) return (NULL); fde = &fdp->fd_ofiles[fd]; if (fde->fde_file == NULL) return (NULL); return (fde); } #ifdef CAPABILITIES static __inline bool fd_modified(struct filedesc *fdp, int fd, seq_t seq) { return (!seq_consistent(fd_seq(fdp->fd_files, fd), seq)); } #endif /* cdir/rdir/jdir manipulation functions. */ void pwd_chdir(struct thread *td, struct vnode *vp); int pwd_chroot(struct thread *td, struct vnode *vp); void pwd_ensure_dirs(void); #endif /* _KERNEL */ #endif /* !_SYS_FILEDESC_H_ */