linux_old1/include/linux/fuse.h

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[PATCH] FUSE - core This patch adds FUSE core. This contains the following files: o inode.c - superblock operations (alloc_inode, destroy_inode, read_inode, clear_inode, put_super, show_options) - registers FUSE filesystem o fuse_i.h - private header file Requirements ============ The most important difference between orinary filesystems and FUSE is the fact, that the filesystem data/metadata is provided by a userspace process run with the privileges of the mount "owner" instead of the kernel, or some remote entity usually running with elevated privileges. The security implication of this is that a non-privileged user must not be able to use this capability to compromise the system. Obvious requirements arising from this are: - mount owner should not be able to get elevated privileges with the help of the mounted filesystem - mount owner should not be able to induce undesired behavior in other users' or the super user's processes - mount owner should not get illegitimate access to information from other users' and the super user's processes These are currently ensured with the following constraints: 1) mount is only allowed to directory or file which the mount owner can modify without limitation (write access + no sticky bit for directories) 2) nosuid,nodev mount options are forced 3) any process running with fsuid different from the owner is denied all access to the filesystem 1) and 2) are ensured by the "fusermount" mount utility which is a setuid root application doing the actual mount operation. 3) is ensured by a check in the permission() method in kernel I started thinking about doing 3) in a different way because Christoph H. made a big deal out of it, saying that FUSE is unacceptable into mainline in this form. The suggested use of private namespaces would be OK, but in their current form have many limitations that make their use impractical (as discussed in this thread). Suggested improvements that would address these limitations: - implement shared subtrees - allow a process to join an existing namespace (make namespaces first-class objects) - implement the namespace creation/joining in a PAM module With all that in place the check of owner against current->fsuid may be removed from the FUSE kernel module, without compromising the security requirements. Suid programs still interesting questions, since they get access even to the private namespace causing some information leak (exact order/timing of filesystem operations performed), giving some ptrace-like capabilities to unprivileged users. BTW this problem is not strictly limited to the namespace approach, since suid programs setting fsuid and accessing users' files will succeed with the current approach too. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 04:10:26 +08:00
/*
FUSE: Filesystem in Userspace
Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
[PATCH] FUSE - core This patch adds FUSE core. This contains the following files: o inode.c - superblock operations (alloc_inode, destroy_inode, read_inode, clear_inode, put_super, show_options) - registers FUSE filesystem o fuse_i.h - private header file Requirements ============ The most important difference between orinary filesystems and FUSE is the fact, that the filesystem data/metadata is provided by a userspace process run with the privileges of the mount "owner" instead of the kernel, or some remote entity usually running with elevated privileges. The security implication of this is that a non-privileged user must not be able to use this capability to compromise the system. Obvious requirements arising from this are: - mount owner should not be able to get elevated privileges with the help of the mounted filesystem - mount owner should not be able to induce undesired behavior in other users' or the super user's processes - mount owner should not get illegitimate access to information from other users' and the super user's processes These are currently ensured with the following constraints: 1) mount is only allowed to directory or file which the mount owner can modify without limitation (write access + no sticky bit for directories) 2) nosuid,nodev mount options are forced 3) any process running with fsuid different from the owner is denied all access to the filesystem 1) and 2) are ensured by the "fusermount" mount utility which is a setuid root application doing the actual mount operation. 3) is ensured by a check in the permission() method in kernel I started thinking about doing 3) in a different way because Christoph H. made a big deal out of it, saying that FUSE is unacceptable into mainline in this form. The suggested use of private namespaces would be OK, but in their current form have many limitations that make their use impractical (as discussed in this thread). Suggested improvements that would address these limitations: - implement shared subtrees - allow a process to join an existing namespace (make namespaces first-class objects) - implement the namespace creation/joining in a PAM module With all that in place the check of owner against current->fsuid may be removed from the FUSE kernel module, without compromising the security requirements. Suid programs still interesting questions, since they get access even to the private namespace causing some information leak (exact order/timing of filesystem operations performed), giving some ptrace-like capabilities to unprivileged users. BTW this problem is not strictly limited to the namespace approach, since suid programs setting fsuid and accessing users' files will succeed with the current approach too. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 04:10:26 +08:00
This program can be distributed under the terms of the GNU GPL.
See the file COPYING.
*/
/* This file defines the kernel interface of FUSE */
#include <asm/types.h>
#include <linux/major.h>
[PATCH] FUSE - core This patch adds FUSE core. This contains the following files: o inode.c - superblock operations (alloc_inode, destroy_inode, read_inode, clear_inode, put_super, show_options) - registers FUSE filesystem o fuse_i.h - private header file Requirements ============ The most important difference between orinary filesystems and FUSE is the fact, that the filesystem data/metadata is provided by a userspace process run with the privileges of the mount "owner" instead of the kernel, or some remote entity usually running with elevated privileges. The security implication of this is that a non-privileged user must not be able to use this capability to compromise the system. Obvious requirements arising from this are: - mount owner should not be able to get elevated privileges with the help of the mounted filesystem - mount owner should not be able to induce undesired behavior in other users' or the super user's processes - mount owner should not get illegitimate access to information from other users' and the super user's processes These are currently ensured with the following constraints: 1) mount is only allowed to directory or file which the mount owner can modify without limitation (write access + no sticky bit for directories) 2) nosuid,nodev mount options are forced 3) any process running with fsuid different from the owner is denied all access to the filesystem 1) and 2) are ensured by the "fusermount" mount utility which is a setuid root application doing the actual mount operation. 3) is ensured by a check in the permission() method in kernel I started thinking about doing 3) in a different way because Christoph H. made a big deal out of it, saying that FUSE is unacceptable into mainline in this form. The suggested use of private namespaces would be OK, but in their current form have many limitations that make their use impractical (as discussed in this thread). Suggested improvements that would address these limitations: - implement shared subtrees - allow a process to join an existing namespace (make namespaces first-class objects) - implement the namespace creation/joining in a PAM module With all that in place the check of owner against current->fsuid may be removed from the FUSE kernel module, without compromising the security requirements. Suid programs still interesting questions, since they get access even to the private namespace causing some information leak (exact order/timing of filesystem operations performed), giving some ptrace-like capabilities to unprivileged users. BTW this problem is not strictly limited to the namespace approach, since suid programs setting fsuid and accessing users' files will succeed with the current approach too. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 04:10:26 +08:00
/** Version number of this interface */
#define FUSE_KERNEL_VERSION 7
[PATCH] FUSE - core This patch adds FUSE core. This contains the following files: o inode.c - superblock operations (alloc_inode, destroy_inode, read_inode, clear_inode, put_super, show_options) - registers FUSE filesystem o fuse_i.h - private header file Requirements ============ The most important difference between orinary filesystems and FUSE is the fact, that the filesystem data/metadata is provided by a userspace process run with the privileges of the mount "owner" instead of the kernel, or some remote entity usually running with elevated privileges. The security implication of this is that a non-privileged user must not be able to use this capability to compromise the system. Obvious requirements arising from this are: - mount owner should not be able to get elevated privileges with the help of the mounted filesystem - mount owner should not be able to induce undesired behavior in other users' or the super user's processes - mount owner should not get illegitimate access to information from other users' and the super user's processes These are currently ensured with the following constraints: 1) mount is only allowed to directory or file which the mount owner can modify without limitation (write access + no sticky bit for directories) 2) nosuid,nodev mount options are forced 3) any process running with fsuid different from the owner is denied all access to the filesystem 1) and 2) are ensured by the "fusermount" mount utility which is a setuid root application doing the actual mount operation. 3) is ensured by a check in the permission() method in kernel I started thinking about doing 3) in a different way because Christoph H. made a big deal out of it, saying that FUSE is unacceptable into mainline in this form. The suggested use of private namespaces would be OK, but in their current form have many limitations that make their use impractical (as discussed in this thread). Suggested improvements that would address these limitations: - implement shared subtrees - allow a process to join an existing namespace (make namespaces first-class objects) - implement the namespace creation/joining in a PAM module With all that in place the check of owner against current->fsuid may be removed from the FUSE kernel module, without compromising the security requirements. Suid programs still interesting questions, since they get access even to the private namespace causing some information leak (exact order/timing of filesystem operations performed), giving some ptrace-like capabilities to unprivileged users. BTW this problem is not strictly limited to the namespace approach, since suid programs setting fsuid and accessing users' files will succeed with the current approach too. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 04:10:26 +08:00
/** Minor version number of this interface */
#define FUSE_KERNEL_MINOR_VERSION 8
[PATCH] FUSE - core This patch adds FUSE core. This contains the following files: o inode.c - superblock operations (alloc_inode, destroy_inode, read_inode, clear_inode, put_super, show_options) - registers FUSE filesystem o fuse_i.h - private header file Requirements ============ The most important difference between orinary filesystems and FUSE is the fact, that the filesystem data/metadata is provided by a userspace process run with the privileges of the mount "owner" instead of the kernel, or some remote entity usually running with elevated privileges. The security implication of this is that a non-privileged user must not be able to use this capability to compromise the system. Obvious requirements arising from this are: - mount owner should not be able to get elevated privileges with the help of the mounted filesystem - mount owner should not be able to induce undesired behavior in other users' or the super user's processes - mount owner should not get illegitimate access to information from other users' and the super user's processes These are currently ensured with the following constraints: 1) mount is only allowed to directory or file which the mount owner can modify without limitation (write access + no sticky bit for directories) 2) nosuid,nodev mount options are forced 3) any process running with fsuid different from the owner is denied all access to the filesystem 1) and 2) are ensured by the "fusermount" mount utility which is a setuid root application doing the actual mount operation. 3) is ensured by a check in the permission() method in kernel I started thinking about doing 3) in a different way because Christoph H. made a big deal out of it, saying that FUSE is unacceptable into mainline in this form. The suggested use of private namespaces would be OK, but in their current form have many limitations that make their use impractical (as discussed in this thread). Suggested improvements that would address these limitations: - implement shared subtrees - allow a process to join an existing namespace (make namespaces first-class objects) - implement the namespace creation/joining in a PAM module With all that in place the check of owner against current->fsuid may be removed from the FUSE kernel module, without compromising the security requirements. Suid programs still interesting questions, since they get access even to the private namespace causing some information leak (exact order/timing of filesystem operations performed), giving some ptrace-like capabilities to unprivileged users. BTW this problem is not strictly limited to the namespace approach, since suid programs setting fsuid and accessing users' files will succeed with the current approach too. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 04:10:26 +08:00
/** The node ID of the root inode */
#define FUSE_ROOT_ID 1
/** The major number of the fuse character device */
#define FUSE_MAJOR MISC_MAJOR
/** The minor number of the fuse character device */
#define FUSE_MINOR 229
/* Make sure all structures are padded to 64bit boundary, so 32bit
userspace works under 64bit kernels */
[PATCH] FUSE - core This patch adds FUSE core. This contains the following files: o inode.c - superblock operations (alloc_inode, destroy_inode, read_inode, clear_inode, put_super, show_options) - registers FUSE filesystem o fuse_i.h - private header file Requirements ============ The most important difference between orinary filesystems and FUSE is the fact, that the filesystem data/metadata is provided by a userspace process run with the privileges of the mount "owner" instead of the kernel, or some remote entity usually running with elevated privileges. The security implication of this is that a non-privileged user must not be able to use this capability to compromise the system. Obvious requirements arising from this are: - mount owner should not be able to get elevated privileges with the help of the mounted filesystem - mount owner should not be able to induce undesired behavior in other users' or the super user's processes - mount owner should not get illegitimate access to information from other users' and the super user's processes These are currently ensured with the following constraints: 1) mount is only allowed to directory or file which the mount owner can modify without limitation (write access + no sticky bit for directories) 2) nosuid,nodev mount options are forced 3) any process running with fsuid different from the owner is denied all access to the filesystem 1) and 2) are ensured by the "fusermount" mount utility which is a setuid root application doing the actual mount operation. 3) is ensured by a check in the permission() method in kernel I started thinking about doing 3) in a different way because Christoph H. made a big deal out of it, saying that FUSE is unacceptable into mainline in this form. The suggested use of private namespaces would be OK, but in their current form have many limitations that make their use impractical (as discussed in this thread). Suggested improvements that would address these limitations: - implement shared subtrees - allow a process to join an existing namespace (make namespaces first-class objects) - implement the namespace creation/joining in a PAM module With all that in place the check of owner against current->fsuid may be removed from the FUSE kernel module, without compromising the security requirements. Suid programs still interesting questions, since they get access even to the private namespace causing some information leak (exact order/timing of filesystem operations performed), giving some ptrace-like capabilities to unprivileged users. BTW this problem is not strictly limited to the namespace approach, since suid programs setting fsuid and accessing users' files will succeed with the current approach too. Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 04:10:26 +08:00
struct fuse_attr {
__u64 ino;
__u64 size;
__u64 blocks;
__u64 atime;
__u64 mtime;
__u64 ctime;
__u32 atimensec;
__u32 mtimensec;
__u32 ctimensec;
__u32 mode;
__u32 nlink;
__u32 uid;
__u32 gid;
__u32 rdev;
};
struct fuse_kstatfs {
__u64 blocks;
__u64 bfree;
__u64 bavail;
__u64 files;
__u64 ffree;
__u32 bsize;
__u32 namelen;
__u32 frsize;
__u32 padding;
__u32 spare[6];
};
struct fuse_file_lock {
__u64 start;
__u64 end;
__u32 type;
__u32 pid; /* tgid */
};
/**
* Bitmasks for fuse_setattr_in.valid
*/
#define FATTR_MODE (1 << 0)
#define FATTR_UID (1 << 1)
#define FATTR_GID (1 << 2)
#define FATTR_SIZE (1 << 3)
#define FATTR_ATIME (1 << 4)
#define FATTR_MTIME (1 << 5)
#define FATTR_FH (1 << 6)
/**
* Flags returned by the OPEN request
*
* FOPEN_DIRECT_IO: bypass page cache for this open file
* FOPEN_KEEP_CACHE: don't invalidate the data cache on open
*/
#define FOPEN_DIRECT_IO (1 << 0)
#define FOPEN_KEEP_CACHE (1 << 1)
/**
* INIT request/reply flags
*/
#define FUSE_ASYNC_READ (1 << 0)
#define FUSE_POSIX_LOCKS (1 << 1)
/**
* Release flags
*/
#define FUSE_RELEASE_FLUSH (1 << 0)
enum fuse_opcode {
FUSE_LOOKUP = 1,
FUSE_FORGET = 2, /* no reply */
FUSE_GETATTR = 3,
FUSE_SETATTR = 4,
FUSE_READLINK = 5,
FUSE_SYMLINK = 6,
FUSE_MKNOD = 8,
FUSE_MKDIR = 9,
FUSE_UNLINK = 10,
FUSE_RMDIR = 11,
FUSE_RENAME = 12,
FUSE_LINK = 13,
FUSE_OPEN = 14,
FUSE_READ = 15,
FUSE_WRITE = 16,
FUSE_STATFS = 17,
FUSE_RELEASE = 18,
FUSE_FSYNC = 20,
FUSE_SETXATTR = 21,
FUSE_GETXATTR = 22,
FUSE_LISTXATTR = 23,
FUSE_REMOVEXATTR = 24,
FUSE_FLUSH = 25,
FUSE_INIT = 26,
FUSE_OPENDIR = 27,
FUSE_READDIR = 28,
FUSE_RELEASEDIR = 29,
FUSE_FSYNCDIR = 30,
FUSE_GETLK = 31,
FUSE_SETLK = 32,
FUSE_SETLKW = 33,
FUSE_ACCESS = 34,
FUSE_CREATE = 35,
FUSE_INTERRUPT = 36,
FUSE_BMAP = 37,
FUSE_DESTROY = 38,
};
/* The read buffer is required to be at least 8k, but may be much larger */
#define FUSE_MIN_READ_BUFFER 8192
struct fuse_entry_out {
__u64 nodeid; /* Inode ID */
__u64 generation; /* Inode generation: nodeid:gen must
be unique for the fs's lifetime */
__u64 entry_valid; /* Cache timeout for the name */
__u64 attr_valid; /* Cache timeout for the attributes */
__u32 entry_valid_nsec;
__u32 attr_valid_nsec;
struct fuse_attr attr;
};
struct fuse_forget_in {
__u64 nlookup;
};
struct fuse_attr_out {
__u64 attr_valid; /* Cache timeout for the attributes */
__u32 attr_valid_nsec;
__u32 dummy;
struct fuse_attr attr;
};
struct fuse_mknod_in {
__u32 mode;
__u32 rdev;
};
struct fuse_mkdir_in {
__u32 mode;
__u32 padding;
};
struct fuse_rename_in {
__u64 newdir;
};
struct fuse_link_in {
__u64 oldnodeid;
};
struct fuse_setattr_in {
__u32 valid;
__u32 padding;
__u64 fh;
__u64 size;
__u64 unused1;
__u64 atime;
__u64 mtime;
__u64 unused2;
__u32 atimensec;
__u32 mtimensec;
__u32 unused3;
__u32 mode;
__u32 unused4;
__u32 uid;
__u32 gid;
__u32 unused5;
};
struct fuse_open_in {
__u32 flags;
__u32 mode;
};
struct fuse_open_out {
__u64 fh;
__u32 open_flags;
__u32 padding;
};
struct fuse_release_in {
__u64 fh;
__u32 flags;
__u32 release_flags;
__u64 lock_owner;
};
struct fuse_flush_in {
__u64 fh;
__u32 unused;
__u32 padding;
__u64 lock_owner;
};
struct fuse_read_in {
__u64 fh;
__u64 offset;
__u32 size;
__u32 padding;
};
struct fuse_write_in {
__u64 fh;
__u64 offset;
__u32 size;
__u32 write_flags;
};
struct fuse_write_out {
__u32 size;
__u32 padding;
};
#define FUSE_COMPAT_STATFS_SIZE 48
struct fuse_statfs_out {
struct fuse_kstatfs st;
};
struct fuse_fsync_in {
__u64 fh;
__u32 fsync_flags;
__u32 padding;
};
struct fuse_setxattr_in {
__u32 size;
__u32 flags;
};
struct fuse_getxattr_in {
__u32 size;
__u32 padding;
};
struct fuse_getxattr_out {
__u32 size;
__u32 padding;
};
struct fuse_lk_in {
__u64 fh;
__u64 owner;
struct fuse_file_lock lk;
};
struct fuse_lk_out {
struct fuse_file_lock lk;
};
struct fuse_access_in {
__u32 mask;
__u32 padding;
};
struct fuse_init_in {
__u32 major;
__u32 minor;
__u32 max_readahead;
__u32 flags;
};
struct fuse_init_out {
__u32 major;
__u32 minor;
__u32 max_readahead;
__u32 flags;
__u32 unused;
__u32 max_write;
};
struct fuse_interrupt_in {
__u64 unique;
};
struct fuse_bmap_in {
__u64 block;
__u32 blocksize;
__u32 padding;
};
struct fuse_bmap_out {
__u64 block;
};
struct fuse_in_header {
__u32 len;
__u32 opcode;
__u64 unique;
__u64 nodeid;
__u32 uid;
__u32 gid;
__u32 pid;
__u32 padding;
};
struct fuse_out_header {
__u32 len;
__s32 error;
__u64 unique;
};
struct fuse_dirent {
__u64 ino;
__u64 off;
__u32 namelen;
__u32 type;
char name[0];
};
#define FUSE_NAME_OFFSET ((unsigned) ((struct fuse_dirent *) 0)->name)
#define FUSE_DIRENT_ALIGN(x) (((x) + sizeof(__u64) - 1) & ~(sizeof(__u64) - 1))
#define FUSE_DIRENT_SIZE(d) \
FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + (d)->namelen)