250 lines
7.3 KiB
C
250 lines
7.3 KiB
C
/*
|
|
* This is <linux/capability.h>
|
|
*
|
|
* Andrew G. Morgan <morgan@kernel.org>
|
|
* Alexander Kjeldaas <astor@guardian.no>
|
|
* with help from Aleph1, Roland Buresund and Andrew Main.
|
|
*
|
|
* See here for the libcap library ("POSIX draft" compliance):
|
|
*
|
|
* ftp://www.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/
|
|
*/
|
|
#ifndef _LINUX_CAPABILITY_H
|
|
#define _LINUX_CAPABILITY_H
|
|
|
|
#include <uapi/linux/capability.h>
|
|
|
|
|
|
#define _KERNEL_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_3
|
|
#define _KERNEL_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_3
|
|
|
|
extern int file_caps_enabled;
|
|
|
|
typedef struct kernel_cap_struct {
|
|
__u32 cap[_KERNEL_CAPABILITY_U32S];
|
|
} kernel_cap_t;
|
|
|
|
/* exact same as vfs_cap_data but in cpu endian and always filled completely */
|
|
struct cpu_vfs_cap_data {
|
|
__u32 magic_etc;
|
|
kernel_cap_t permitted;
|
|
kernel_cap_t inheritable;
|
|
};
|
|
|
|
#define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct))
|
|
#define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t))
|
|
|
|
|
|
struct file;
|
|
struct inode;
|
|
struct dentry;
|
|
struct task_struct;
|
|
struct user_namespace;
|
|
|
|
extern const kernel_cap_t __cap_empty_set;
|
|
extern const kernel_cap_t __cap_init_eff_set;
|
|
|
|
/*
|
|
* Internal kernel functions only
|
|
*/
|
|
|
|
#define CAP_FOR_EACH_U32(__capi) \
|
|
for (__capi = 0; __capi < _KERNEL_CAPABILITY_U32S; ++__capi)
|
|
|
|
/*
|
|
* CAP_FS_MASK and CAP_NFSD_MASKS:
|
|
*
|
|
* The fs mask is all the privileges that fsuid==0 historically meant.
|
|
* At one time in the past, that included CAP_MKNOD and CAP_LINUX_IMMUTABLE.
|
|
*
|
|
* It has never meant setting security.* and trusted.* xattrs.
|
|
*
|
|
* We could also define fsmask as follows:
|
|
* 1. CAP_FS_MASK is the privilege to bypass all fs-related DAC permissions
|
|
* 2. The security.* and trusted.* xattrs are fs-related MAC permissions
|
|
*/
|
|
|
|
# define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \
|
|
| CAP_TO_MASK(CAP_MKNOD) \
|
|
| CAP_TO_MASK(CAP_DAC_OVERRIDE) \
|
|
| CAP_TO_MASK(CAP_DAC_READ_SEARCH) \
|
|
| CAP_TO_MASK(CAP_FOWNER) \
|
|
| CAP_TO_MASK(CAP_FSETID))
|
|
|
|
# define CAP_FS_MASK_B1 (CAP_TO_MASK(CAP_MAC_OVERRIDE))
|
|
|
|
#if _KERNEL_CAPABILITY_U32S != 2
|
|
# error Fix up hand-coded capability macro initializers
|
|
#else /* HAND-CODED capability initializers */
|
|
|
|
#define CAP_LAST_U32 ((_KERNEL_CAPABILITY_U32S) - 1)
|
|
#define CAP_LAST_U32_VALID_MASK (CAP_TO_MASK(CAP_LAST_CAP + 1) -1)
|
|
|
|
# define CAP_EMPTY_SET ((kernel_cap_t){{ 0, 0 }})
|
|
# define CAP_FULL_SET ((kernel_cap_t){{ ~0, CAP_LAST_U32_VALID_MASK }})
|
|
# define CAP_FS_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \
|
|
| CAP_TO_MASK(CAP_LINUX_IMMUTABLE), \
|
|
CAP_FS_MASK_B1 } })
|
|
# define CAP_NFSD_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \
|
|
| CAP_TO_MASK(CAP_SYS_RESOURCE), \
|
|
CAP_FS_MASK_B1 } })
|
|
|
|
#endif /* _KERNEL_CAPABILITY_U32S != 2 */
|
|
|
|
# define cap_clear(c) do { (c) = __cap_empty_set; } while (0)
|
|
|
|
#define cap_raise(c, flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag))
|
|
#define cap_lower(c, flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag))
|
|
#define cap_raised(c, flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag))
|
|
|
|
#define CAP_BOP_ALL(c, a, b, OP) \
|
|
do { \
|
|
unsigned __capi; \
|
|
CAP_FOR_EACH_U32(__capi) { \
|
|
c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \
|
|
} \
|
|
} while (0)
|
|
|
|
#define CAP_UOP_ALL(c, a, OP) \
|
|
do { \
|
|
unsigned __capi; \
|
|
CAP_FOR_EACH_U32(__capi) { \
|
|
c.cap[__capi] = OP a.cap[__capi]; \
|
|
} \
|
|
} while (0)
|
|
|
|
static inline kernel_cap_t cap_combine(const kernel_cap_t a,
|
|
const kernel_cap_t b)
|
|
{
|
|
kernel_cap_t dest;
|
|
CAP_BOP_ALL(dest, a, b, |);
|
|
return dest;
|
|
}
|
|
|
|
static inline kernel_cap_t cap_intersect(const kernel_cap_t a,
|
|
const kernel_cap_t b)
|
|
{
|
|
kernel_cap_t dest;
|
|
CAP_BOP_ALL(dest, a, b, &);
|
|
return dest;
|
|
}
|
|
|
|
static inline kernel_cap_t cap_drop(const kernel_cap_t a,
|
|
const kernel_cap_t drop)
|
|
{
|
|
kernel_cap_t dest;
|
|
CAP_BOP_ALL(dest, a, drop, &~);
|
|
return dest;
|
|
}
|
|
|
|
static inline kernel_cap_t cap_invert(const kernel_cap_t c)
|
|
{
|
|
kernel_cap_t dest;
|
|
CAP_UOP_ALL(dest, c, ~);
|
|
return dest;
|
|
}
|
|
|
|
static inline bool cap_isclear(const kernel_cap_t a)
|
|
{
|
|
unsigned __capi;
|
|
CAP_FOR_EACH_U32(__capi) {
|
|
if (a.cap[__capi] != 0)
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Check if "a" is a subset of "set".
|
|
* return true if ALL of the capabilities in "a" are also in "set"
|
|
* cap_issubset(0101, 1111) will return true
|
|
* return false if ANY of the capabilities in "a" are not in "set"
|
|
* cap_issubset(1111, 0101) will return false
|
|
*/
|
|
static inline bool cap_issubset(const kernel_cap_t a, const kernel_cap_t set)
|
|
{
|
|
kernel_cap_t dest;
|
|
dest = cap_drop(a, set);
|
|
return cap_isclear(dest);
|
|
}
|
|
|
|
/* Used to decide between falling back on the old suser() or fsuser(). */
|
|
|
|
static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a)
|
|
{
|
|
const kernel_cap_t __cap_fs_set = CAP_FS_SET;
|
|
return cap_drop(a, __cap_fs_set);
|
|
}
|
|
|
|
static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a,
|
|
const kernel_cap_t permitted)
|
|
{
|
|
const kernel_cap_t __cap_fs_set = CAP_FS_SET;
|
|
return cap_combine(a,
|
|
cap_intersect(permitted, __cap_fs_set));
|
|
}
|
|
|
|
static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a)
|
|
{
|
|
const kernel_cap_t __cap_fs_set = CAP_NFSD_SET;
|
|
return cap_drop(a, __cap_fs_set);
|
|
}
|
|
|
|
static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a,
|
|
const kernel_cap_t permitted)
|
|
{
|
|
const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET;
|
|
return cap_combine(a,
|
|
cap_intersect(permitted, __cap_nfsd_set));
|
|
}
|
|
|
|
#ifdef CONFIG_MULTIUSER
|
|
extern bool has_capability(struct task_struct *t, int cap);
|
|
extern bool has_ns_capability(struct task_struct *t,
|
|
struct user_namespace *ns, int cap);
|
|
extern bool has_capability_noaudit(struct task_struct *t, int cap);
|
|
extern bool has_ns_capability_noaudit(struct task_struct *t,
|
|
struct user_namespace *ns, int cap);
|
|
extern bool capable(int cap);
|
|
extern bool ns_capable(struct user_namespace *ns, int cap);
|
|
extern bool ns_capable_noaudit(struct user_namespace *ns, int cap);
|
|
#else
|
|
static inline bool has_capability(struct task_struct *t, int cap)
|
|
{
|
|
return true;
|
|
}
|
|
static inline bool has_ns_capability(struct task_struct *t,
|
|
struct user_namespace *ns, int cap)
|
|
{
|
|
return true;
|
|
}
|
|
static inline bool has_capability_noaudit(struct task_struct *t, int cap)
|
|
{
|
|
return true;
|
|
}
|
|
static inline bool has_ns_capability_noaudit(struct task_struct *t,
|
|
struct user_namespace *ns, int cap)
|
|
{
|
|
return true;
|
|
}
|
|
static inline bool capable(int cap)
|
|
{
|
|
return true;
|
|
}
|
|
static inline bool ns_capable(struct user_namespace *ns, int cap)
|
|
{
|
|
return true;
|
|
}
|
|
static inline bool ns_capable_noaudit(struct user_namespace *ns, int cap)
|
|
{
|
|
return true;
|
|
}
|
|
#endif /* CONFIG_MULTIUSER */
|
|
extern bool capable_wrt_inode_uidgid(const struct inode *inode, int cap);
|
|
extern bool file_ns_capable(const struct file *file, struct user_namespace *ns, int cap);
|
|
|
|
/* audit system wants to get cap info from files as well */
|
|
extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps);
|
|
|
|
#endif /* !_LINUX_CAPABILITY_H */
|