diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /kernel/capability.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'kernel/capability.c')
-rw-r--r-- | kernel/capability.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/kernel/capability.c b/kernel/capability.c new file mode 100644 index 000000000000..64db1ee820c2 --- /dev/null +++ b/kernel/capability.c | |||
@@ -0,0 +1,220 @@ | |||
1 | /* | ||
2 | * linux/kernel/capability.c | ||
3 | * | ||
4 | * Copyright (C) 1997 Andrew Main <zefram@fysh.org> | ||
5 | * | ||
6 | * Integrated into 2.1.97+, Andrew G. Morgan <morgan@transmeta.com> | ||
7 | * 30 May 2002: Cleanup, Robert M. Love <rml@tech9.net> | ||
8 | */ | ||
9 | |||
10 | #include <linux/mm.h> | ||
11 | #include <linux/module.h> | ||
12 | #include <linux/security.h> | ||
13 | #include <linux/syscalls.h> | ||
14 | #include <asm/uaccess.h> | ||
15 | |||
16 | unsigned securebits = SECUREBITS_DEFAULT; /* systemwide security settings */ | ||
17 | kernel_cap_t cap_bset = CAP_INIT_EFF_SET; | ||
18 | |||
19 | EXPORT_SYMBOL(securebits); | ||
20 | EXPORT_SYMBOL(cap_bset); | ||
21 | |||
22 | /* | ||
23 | * This lock protects task->cap_* for all tasks including current. | ||
24 | * Locking rule: acquire this prior to tasklist_lock. | ||
25 | */ | ||
26 | static DEFINE_SPINLOCK(task_capability_lock); | ||
27 | |||
28 | /* | ||
29 | * For sys_getproccap() and sys_setproccap(), any of the three | ||
30 | * capability set pointers may be NULL -- indicating that that set is | ||
31 | * uninteresting and/or not to be changed. | ||
32 | */ | ||
33 | |||
34 | /* | ||
35 | * sys_capget - get the capabilities of a given process. | ||
36 | */ | ||
37 | asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr) | ||
38 | { | ||
39 | int ret = 0; | ||
40 | pid_t pid; | ||
41 | __u32 version; | ||
42 | task_t *target; | ||
43 | struct __user_cap_data_struct data; | ||
44 | |||
45 | if (get_user(version, &header->version)) | ||
46 | return -EFAULT; | ||
47 | |||
48 | if (version != _LINUX_CAPABILITY_VERSION) { | ||
49 | if (put_user(_LINUX_CAPABILITY_VERSION, &header->version)) | ||
50 | return -EFAULT; | ||
51 | return -EINVAL; | ||
52 | } | ||
53 | |||
54 | if (get_user(pid, &header->pid)) | ||
55 | return -EFAULT; | ||
56 | |||
57 | if (pid < 0) | ||
58 | return -EINVAL; | ||
59 | |||
60 | spin_lock(&task_capability_lock); | ||
61 | read_lock(&tasklist_lock); | ||
62 | |||
63 | if (pid && pid != current->pid) { | ||
64 | target = find_task_by_pid(pid); | ||
65 | if (!target) { | ||
66 | ret = -ESRCH; | ||
67 | goto out; | ||
68 | } | ||
69 | } else | ||
70 | target = current; | ||
71 | |||
72 | ret = security_capget(target, &data.effective, &data.inheritable, &data.permitted); | ||
73 | |||
74 | out: | ||
75 | read_unlock(&tasklist_lock); | ||
76 | spin_unlock(&task_capability_lock); | ||
77 | |||
78 | if (!ret && copy_to_user(dataptr, &data, sizeof data)) | ||
79 | return -EFAULT; | ||
80 | |||
81 | return ret; | ||
82 | } | ||
83 | |||
84 | /* | ||
85 | * cap_set_pg - set capabilities for all processes in a given process | ||
86 | * group. We call this holding task_capability_lock and tasklist_lock. | ||
87 | */ | ||
88 | static inline int cap_set_pg(int pgrp, kernel_cap_t *effective, | ||
89 | kernel_cap_t *inheritable, | ||
90 | kernel_cap_t *permitted) | ||
91 | { | ||
92 | task_t *g, *target; | ||
93 | int ret = -EPERM; | ||
94 | int found = 0; | ||
95 | |||
96 | do_each_task_pid(pgrp, PIDTYPE_PGID, g) { | ||
97 | target = g; | ||
98 | while_each_thread(g, target) { | ||
99 | if (!security_capset_check(target, effective, | ||
100 | inheritable, | ||
101 | permitted)) { | ||
102 | security_capset_set(target, effective, | ||
103 | inheritable, | ||
104 | permitted); | ||
105 | ret = 0; | ||
106 | } | ||
107 | found = 1; | ||
108 | } | ||
109 | } while_each_task_pid(pgrp, PIDTYPE_PGID, g); | ||
110 | |||
111 | if (!found) | ||
112 | ret = 0; | ||
113 | return ret; | ||
114 | } | ||
115 | |||
116 | /* | ||
117 | * cap_set_all - set capabilities for all processes other than init | ||
118 | * and self. We call this holding task_capability_lock and tasklist_lock. | ||
119 | */ | ||
120 | static inline int cap_set_all(kernel_cap_t *effective, | ||
121 | kernel_cap_t *inheritable, | ||
122 | kernel_cap_t *permitted) | ||
123 | { | ||
124 | task_t *g, *target; | ||
125 | int ret = -EPERM; | ||
126 | int found = 0; | ||
127 | |||
128 | do_each_thread(g, target) { | ||
129 | if (target == current || target->pid == 1) | ||
130 | continue; | ||
131 | found = 1; | ||
132 | if (security_capset_check(target, effective, inheritable, | ||
133 | permitted)) | ||
134 | continue; | ||
135 | ret = 0; | ||
136 | security_capset_set(target, effective, inheritable, permitted); | ||
137 | } while_each_thread(g, target); | ||
138 | |||
139 | if (!found) | ||
140 | ret = 0; | ||
141 | return ret; | ||
142 | } | ||
143 | |||
144 | /* | ||
145 | * sys_capset - set capabilities for a given process, all processes, or all | ||
146 | * processes in a given process group. | ||
147 | * | ||
148 | * The restrictions on setting capabilities are specified as: | ||
149 | * | ||
150 | * [pid is for the 'target' task. 'current' is the calling task.] | ||
151 | * | ||
152 | * I: any raised capabilities must be a subset of the (old current) permitted | ||
153 | * P: any raised capabilities must be a subset of the (old current) permitted | ||
154 | * E: must be set to a subset of (new target) permitted | ||
155 | */ | ||
156 | asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data) | ||
157 | { | ||
158 | kernel_cap_t inheritable, permitted, effective; | ||
159 | __u32 version; | ||
160 | task_t *target; | ||
161 | int ret; | ||
162 | pid_t pid; | ||
163 | |||
164 | if (get_user(version, &header->version)) | ||
165 | return -EFAULT; | ||
166 | |||
167 | if (version != _LINUX_CAPABILITY_VERSION) { | ||
168 | if (put_user(_LINUX_CAPABILITY_VERSION, &header->version)) | ||
169 | return -EFAULT; | ||
170 | return -EINVAL; | ||
171 | } | ||
172 | |||
173 | if (get_user(pid, &header->pid)) | ||
174 | return -EFAULT; | ||
175 | |||
176 | if (pid && pid != current->pid && !capable(CAP_SETPCAP)) | ||
177 | return -EPERM; | ||
178 | |||
179 | if (copy_from_user(&effective, &data->effective, sizeof(effective)) || | ||
180 | copy_from_user(&inheritable, &data->inheritable, sizeof(inheritable)) || | ||
181 | copy_from_user(&permitted, &data->permitted, sizeof(permitted))) | ||
182 | return -EFAULT; | ||
183 | |||
184 | spin_lock(&task_capability_lock); | ||
185 | read_lock(&tasklist_lock); | ||
186 | |||
187 | if (pid > 0 && pid != current->pid) { | ||
188 | target = find_task_by_pid(pid); | ||
189 | if (!target) { | ||
190 | ret = -ESRCH; | ||
191 | goto out; | ||
192 | } | ||
193 | } else | ||
194 | target = current; | ||
195 | |||
196 | ret = 0; | ||
197 | |||
198 | /* having verified that the proposed changes are legal, | ||
199 | we now put them into effect. */ | ||
200 | if (pid < 0) { | ||
201 | if (pid == -1) /* all procs other than current and init */ | ||
202 | ret = cap_set_all(&effective, &inheritable, &permitted); | ||
203 | |||
204 | else /* all procs in process group */ | ||
205 | ret = cap_set_pg(-pid, &effective, &inheritable, | ||
206 | &permitted); | ||
207 | } else { | ||
208 | ret = security_capset_check(target, &effective, &inheritable, | ||
209 | &permitted); | ||
210 | if (!ret) | ||
211 | security_capset_set(target, &effective, &inheritable, | ||
212 | &permitted); | ||
213 | } | ||
214 | |||
215 | out: | ||
216 | read_unlock(&tasklist_lock); | ||
217 | spin_unlock(&task_capability_lock); | ||
218 | |||
219 | return ret; | ||
220 | } | ||