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-rw-r--r--kernel/include/linux/capability.h251
1 files changed, 251 insertions, 0 deletions
diff --git a/kernel/include/linux/capability.h b/kernel/include/linux/capability.h
new file mode 100644
index 000000000..af9f0b9e8
--- /dev/null
+++ b/kernel/include/linux/capability.h
@@ -0,0 +1,251 @@
+/*
+ * 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 user_namespace;
+
+struct user_namespace *current_user_ns(void);
+
+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 int cap_isclear(const kernel_cap_t a)
+{
+ unsigned __capi;
+ CAP_FOR_EACH_U32(__capi) {
+ if (a.cap[__capi] != 0)
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * Check if "a" is a subset of "set".
+ * return 1 if ALL of the capabilities in "a" are also in "set"
+ * cap_issubset(0101, 1111) will return 1
+ * return 0 if ANY of the capabilities in "a" are not in "set"
+ * cap_issubset(1111, 0101) will return 0
+ */
+static inline int 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 int cap_is_fs_cap(int cap)
+{
+ const kernel_cap_t __cap_fs_set = CAP_FS_SET;
+ return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]);
+}
+
+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);
+#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;
+}
+#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 */