/* * 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_MULTIUSERextern 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);#elsestatic 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 privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode);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);extern bool ptracer_capable(struct task_struct *tsk, struct user_namespace *ns); /* 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 */