Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * This is <linux/capability.h> | |
3 | * | |
b5376771 | 4 | * Andrew G. Morgan <morgan@kernel.org> |
1da177e4 LT |
5 | * Alexander Kjeldaas <astor@guardian.no> |
6 | * with help from Aleph1, Roland Buresund and Andrew Main. | |
7 | * | |
8 | * See here for the libcap library ("POSIX draft" compliance): | |
9 | * | |
bcf56442 | 10 | * ftp://www.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/ |
b5376771 | 11 | */ |
1da177e4 LT |
12 | #ifndef _LINUX_CAPABILITY_H |
13 | #define _LINUX_CAPABILITY_H | |
14 | ||
607ca46e | 15 | #include <uapi/linux/capability.h> |
e338d263 | 16 | |
ca05a99a AM |
17 | |
18 | #define _KERNEL_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_3 | |
19 | #define _KERNEL_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_3 | |
1da177e4 | 20 | |
9fa91d99 | 21 | extern int file_caps_enabled; |
9fa91d99 | 22 | |
1da177e4 | 23 | typedef struct kernel_cap_struct { |
ca05a99a | 24 | __u32 cap[_KERNEL_CAPABILITY_U32S]; |
1da177e4 LT |
25 | } kernel_cap_t; |
26 | ||
c0b00441 EP |
27 | /* exact same as vfs_cap_data but in cpu endian and always filled completely */ |
28 | struct cpu_vfs_cap_data { | |
29 | __u32 magic_etc; | |
30 | kernel_cap_t permitted; | |
31 | kernel_cap_t inheritable; | |
32 | }; | |
33 | ||
e338d263 | 34 | #define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct)) |
1da177e4 LT |
35 | #define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t)) |
36 | ||
1da177e4 | 37 | |
1a48e2ac | 38 | struct inode; |
3486740a SH |
39 | struct dentry; |
40 | struct user_namespace; | |
41 | ||
3486740a SH |
42 | struct user_namespace *current_user_ns(void); |
43 | ||
44 | extern const kernel_cap_t __cap_empty_set; | |
3486740a SH |
45 | extern const kernel_cap_t __cap_init_eff_set; |
46 | ||
1da177e4 LT |
47 | /* |
48 | * Internal kernel functions only | |
49 | */ | |
b5376771 | 50 | |
e338d263 | 51 | #define CAP_FOR_EACH_U32(__capi) \ |
ca05a99a | 52 | for (__capi = 0; __capi < _KERNEL_CAPABILITY_U32S; ++__capi) |
e338d263 | 53 | |
0ad30b8f SH |
54 | /* |
55 | * CAP_FS_MASK and CAP_NFSD_MASKS: | |
56 | * | |
57 | * The fs mask is all the privileges that fsuid==0 historically meant. | |
58 | * At one time in the past, that included CAP_MKNOD and CAP_LINUX_IMMUTABLE. | |
59 | * | |
60 | * It has never meant setting security.* and trusted.* xattrs. | |
61 | * | |
62 | * We could also define fsmask as follows: | |
63 | * 1. CAP_FS_MASK is the privilege to bypass all fs-related DAC permissions | |
64 | * 2. The security.* and trusted.* xattrs are fs-related MAC permissions | |
65 | */ | |
66 | ||
e338d263 | 67 | # define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \ |
0ad30b8f | 68 | | CAP_TO_MASK(CAP_MKNOD) \ |
e338d263 AM |
69 | | CAP_TO_MASK(CAP_DAC_OVERRIDE) \ |
70 | | CAP_TO_MASK(CAP_DAC_READ_SEARCH) \ | |
71 | | CAP_TO_MASK(CAP_FOWNER) \ | |
72 | | CAP_TO_MASK(CAP_FSETID)) | |
73 | ||
e114e473 CS |
74 | # define CAP_FS_MASK_B1 (CAP_TO_MASK(CAP_MAC_OVERRIDE)) |
75 | ||
ca05a99a | 76 | #if _KERNEL_CAPABILITY_U32S != 2 |
e338d263 AM |
77 | # error Fix up hand-coded capability macro initializers |
78 | #else /* HAND-CODED capability initializers */ | |
79 | ||
25f2ea9f DH |
80 | # define CAP_EMPTY_SET ((kernel_cap_t){{ 0, 0 }}) |
81 | # define CAP_FULL_SET ((kernel_cap_t){{ ~0, ~0 }}) | |
0ad30b8f SH |
82 | # define CAP_FS_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \ |
83 | | CAP_TO_MASK(CAP_LINUX_IMMUTABLE), \ | |
84 | CAP_FS_MASK_B1 } }) | |
76a67ec6 | 85 | # define CAP_NFSD_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \ |
0ad30b8f SH |
86 | | CAP_TO_MASK(CAP_SYS_RESOURCE), \ |
87 | CAP_FS_MASK_B1 } }) | |
e338d263 | 88 | |
ca05a99a | 89 | #endif /* _KERNEL_CAPABILITY_U32S != 2 */ |
e338d263 | 90 | |
e338d263 | 91 | # define cap_clear(c) do { (c) = __cap_empty_set; } while (0) |
e338d263 AM |
92 | |
93 | #define cap_raise(c, flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag)) | |
94 | #define cap_lower(c, flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag)) | |
95 | #define cap_raised(c, flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag)) | |
96 | ||
97 | #define CAP_BOP_ALL(c, a, b, OP) \ | |
98 | do { \ | |
99 | unsigned __capi; \ | |
100 | CAP_FOR_EACH_U32(__capi) { \ | |
101 | c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \ | |
102 | } \ | |
103 | } while (0) | |
104 | ||
105 | #define CAP_UOP_ALL(c, a, OP) \ | |
106 | do { \ | |
107 | unsigned __capi; \ | |
108 | CAP_FOR_EACH_U32(__capi) { \ | |
109 | c.cap[__capi] = OP a.cap[__capi]; \ | |
110 | } \ | |
111 | } while (0) | |
112 | ||
113 | static inline kernel_cap_t cap_combine(const kernel_cap_t a, | |
114 | const kernel_cap_t b) | |
115 | { | |
116 | kernel_cap_t dest; | |
117 | CAP_BOP_ALL(dest, a, b, |); | |
118 | return dest; | |
119 | } | |
1da177e4 | 120 | |
e338d263 AM |
121 | static inline kernel_cap_t cap_intersect(const kernel_cap_t a, |
122 | const kernel_cap_t b) | |
123 | { | |
124 | kernel_cap_t dest; | |
125 | CAP_BOP_ALL(dest, a, b, &); | |
126 | return dest; | |
127 | } | |
1da177e4 | 128 | |
e338d263 AM |
129 | static inline kernel_cap_t cap_drop(const kernel_cap_t a, |
130 | const kernel_cap_t drop) | |
131 | { | |
132 | kernel_cap_t dest; | |
133 | CAP_BOP_ALL(dest, a, drop, &~); | |
134 | return dest; | |
135 | } | |
1da177e4 | 136 | |
e338d263 AM |
137 | static inline kernel_cap_t cap_invert(const kernel_cap_t c) |
138 | { | |
139 | kernel_cap_t dest; | |
140 | CAP_UOP_ALL(dest, c, ~); | |
141 | return dest; | |
142 | } | |
1da177e4 | 143 | |
e338d263 AM |
144 | static inline int cap_isclear(const kernel_cap_t a) |
145 | { | |
146 | unsigned __capi; | |
147 | CAP_FOR_EACH_U32(__capi) { | |
148 | if (a.cap[__capi] != 0) | |
149 | return 0; | |
150 | } | |
151 | return 1; | |
152 | } | |
1da177e4 | 153 | |
9d36be76 EP |
154 | /* |
155 | * Check if "a" is a subset of "set". | |
156 | * return 1 if ALL of the capabilities in "a" are also in "set" | |
157 | * cap_issubset(0101, 1111) will return 1 | |
158 | * return 0 if ANY of the capabilities in "a" are not in "set" | |
159 | * cap_issubset(1111, 0101) will return 0 | |
160 | */ | |
e338d263 AM |
161 | static inline int cap_issubset(const kernel_cap_t a, const kernel_cap_t set) |
162 | { | |
163 | kernel_cap_t dest; | |
164 | dest = cap_drop(a, set); | |
165 | return cap_isclear(dest); | |
166 | } | |
1da177e4 | 167 | |
e338d263 | 168 | /* Used to decide between falling back on the old suser() or fsuser(). */ |
1da177e4 | 169 | |
e338d263 | 170 | static inline int cap_is_fs_cap(int cap) |
1da177e4 | 171 | { |
e338d263 AM |
172 | const kernel_cap_t __cap_fs_set = CAP_FS_SET; |
173 | return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]); | |
1da177e4 LT |
174 | } |
175 | ||
e338d263 | 176 | static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a) |
1da177e4 | 177 | { |
e338d263 AM |
178 | const kernel_cap_t __cap_fs_set = CAP_FS_SET; |
179 | return cap_drop(a, __cap_fs_set); | |
1da177e4 LT |
180 | } |
181 | ||
e338d263 AM |
182 | static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a, |
183 | const kernel_cap_t permitted) | |
1da177e4 | 184 | { |
e338d263 AM |
185 | const kernel_cap_t __cap_fs_set = CAP_FS_SET; |
186 | return cap_combine(a, | |
187 | cap_intersect(permitted, __cap_fs_set)); | |
1da177e4 LT |
188 | } |
189 | ||
e338d263 | 190 | static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a) |
1da177e4 | 191 | { |
e338d263 AM |
192 | const kernel_cap_t __cap_fs_set = CAP_NFSD_SET; |
193 | return cap_drop(a, __cap_fs_set); | |
1da177e4 LT |
194 | } |
195 | ||
e338d263 AM |
196 | static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a, |
197 | const kernel_cap_t permitted) | |
198 | { | |
199 | const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET; | |
200 | return cap_combine(a, | |
201 | cap_intersect(permitted, __cap_nfsd_set)); | |
202 | } | |
1da177e4 | 203 | |
3263245d SH |
204 | extern bool has_capability(struct task_struct *t, int cap); |
205 | extern bool has_ns_capability(struct task_struct *t, | |
206 | struct user_namespace *ns, int cap); | |
207 | extern bool has_capability_noaudit(struct task_struct *t, int cap); | |
7b61d648 EP |
208 | extern bool has_ns_capability_noaudit(struct task_struct *t, |
209 | struct user_namespace *ns, int cap); | |
3486740a SH |
210 | extern bool capable(int cap); |
211 | extern bool ns_capable(struct user_namespace *ns, int cap); | |
47a150ed | 212 | extern bool nsown_capable(int cap); |
1a48e2ac | 213 | extern bool inode_capable(const struct inode *inode, int cap); |
c59ede7b | 214 | |
851f7ff5 | 215 | /* audit system wants to get cap info from files as well */ |
851f7ff5 EP |
216 | extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps); |
217 | ||
1da177e4 | 218 | #endif /* !_LINUX_CAPABILITY_H */ |