fsldma: simplify IRQ probing and handling
[linux-3.10.git] / security / tomoyo / tomoyo.c
1 /*
2  * security/tomoyo/tomoyo.c
3  *
4  * LSM hooks for TOMOYO Linux.
5  *
6  * Copyright (C) 2005-2009  NTT DATA CORPORATION
7  *
8  * Version: 2.2.0   2009/04/01
9  *
10  */
11
12 #include <linux/security.h>
13 #include "common.h"
14 #include "tomoyo.h"
15 #include "realpath.h"
16
17 static int tomoyo_cred_alloc_blank(struct cred *new, gfp_t gfp)
18 {
19         new->security = NULL;
20         return 0;
21 }
22
23 static int tomoyo_cred_prepare(struct cred *new, const struct cred *old,
24                                gfp_t gfp)
25 {
26         /*
27          * Since "struct tomoyo_domain_info *" is a sharable pointer,
28          * we don't need to duplicate.
29          */
30         new->security = old->security;
31         return 0;
32 }
33
34 static void tomoyo_cred_transfer(struct cred *new, const struct cred *old)
35 {
36         /*
37          * Since "struct tomoyo_domain_info *" is a sharable pointer,
38          * we don't need to duplicate.
39          */
40         new->security = old->security;
41 }
42
43 static int tomoyo_bprm_set_creds(struct linux_binprm *bprm)
44 {
45         int rc;
46
47         rc = cap_bprm_set_creds(bprm);
48         if (rc)
49                 return rc;
50
51         /*
52          * Do only if this function is called for the first time of an execve
53          * operation.
54          */
55         if (bprm->cred_prepared)
56                 return 0;
57         /*
58          * Load policy if /sbin/tomoyo-init exists and /sbin/init is requested
59          * for the first time.
60          */
61         if (!tomoyo_policy_loaded)
62                 tomoyo_load_policy(bprm->filename);
63         /*
64          * Tell tomoyo_bprm_check_security() is called for the first time of an
65          * execve operation.
66          */
67         bprm->cred->security = NULL;
68         return 0;
69 }
70
71 static int tomoyo_bprm_check_security(struct linux_binprm *bprm)
72 {
73         struct tomoyo_domain_info *domain = bprm->cred->security;
74
75         /*
76          * Execute permission is checked against pathname passed to do_execve()
77          * using current domain.
78          */
79         if (!domain)
80                 return tomoyo_find_next_domain(bprm);
81         /*
82          * Read permission is checked against interpreters using next domain.
83          */
84         return tomoyo_check_open_permission(domain, &bprm->file->f_path, O_RDONLY);
85 }
86
87 static int tomoyo_path_truncate(struct path *path, loff_t length,
88                                 unsigned int time_attrs)
89 {
90         return tomoyo_check_1path_perm(tomoyo_domain(),
91                                        TOMOYO_TYPE_TRUNCATE_ACL,
92                                        path);
93 }
94
95 static int tomoyo_path_unlink(struct path *parent, struct dentry *dentry)
96 {
97         struct path path = { parent->mnt, dentry };
98         return tomoyo_check_1path_perm(tomoyo_domain(),
99                                        TOMOYO_TYPE_UNLINK_ACL,
100                                        &path);
101 }
102
103 static int tomoyo_path_mkdir(struct path *parent, struct dentry *dentry,
104                              int mode)
105 {
106         struct path path = { parent->mnt, dentry };
107         return tomoyo_check_1path_perm(tomoyo_domain(),
108                                        TOMOYO_TYPE_MKDIR_ACL,
109                                        &path);
110 }
111
112 static int tomoyo_path_rmdir(struct path *parent, struct dentry *dentry)
113 {
114         struct path path = { parent->mnt, dentry };
115         return tomoyo_check_1path_perm(tomoyo_domain(),
116                                        TOMOYO_TYPE_RMDIR_ACL,
117                                        &path);
118 }
119
120 static int tomoyo_path_symlink(struct path *parent, struct dentry *dentry,
121                                const char *old_name)
122 {
123         struct path path = { parent->mnt, dentry };
124         return tomoyo_check_1path_perm(tomoyo_domain(),
125                                        TOMOYO_TYPE_SYMLINK_ACL,
126                                        &path);
127 }
128
129 static int tomoyo_path_mknod(struct path *parent, struct dentry *dentry,
130                              int mode, unsigned int dev)
131 {
132         struct path path = { parent->mnt, dentry };
133         int type = TOMOYO_TYPE_CREATE_ACL;
134
135         switch (mode & S_IFMT) {
136         case S_IFCHR:
137                 type = TOMOYO_TYPE_MKCHAR_ACL;
138                 break;
139         case S_IFBLK:
140                 type = TOMOYO_TYPE_MKBLOCK_ACL;
141                 break;
142         case S_IFIFO:
143                 type = TOMOYO_TYPE_MKFIFO_ACL;
144                 break;
145         case S_IFSOCK:
146                 type = TOMOYO_TYPE_MKSOCK_ACL;
147                 break;
148         }
149         return tomoyo_check_1path_perm(tomoyo_domain(),
150                                        type, &path);
151 }
152
153 static int tomoyo_path_link(struct dentry *old_dentry, struct path *new_dir,
154                             struct dentry *new_dentry)
155 {
156         struct path path1 = { new_dir->mnt, old_dentry };
157         struct path path2 = { new_dir->mnt, new_dentry };
158         return tomoyo_check_2path_perm(tomoyo_domain(),
159                                        TOMOYO_TYPE_LINK_ACL,
160                                        &path1, &path2);
161 }
162
163 static int tomoyo_path_rename(struct path *old_parent,
164                               struct dentry *old_dentry,
165                               struct path *new_parent,
166                               struct dentry *new_dentry)
167 {
168         struct path path1 = { old_parent->mnt, old_dentry };
169         struct path path2 = { new_parent->mnt, new_dentry };
170         return tomoyo_check_2path_perm(tomoyo_domain(),
171                                        TOMOYO_TYPE_RENAME_ACL,
172                                        &path1, &path2);
173 }
174
175 static int tomoyo_file_fcntl(struct file *file, unsigned int cmd,
176                              unsigned long arg)
177 {
178         if (cmd == F_SETFL && ((arg ^ file->f_flags) & O_APPEND))
179                 return tomoyo_check_rewrite_permission(tomoyo_domain(), file);
180         return 0;
181 }
182
183 static int tomoyo_dentry_open(struct file *f, const struct cred *cred)
184 {
185         int flags = f->f_flags;
186         /* Don't check read permission here if called from do_execve(). */
187         if (current->in_execve)
188                 return 0;
189         return tomoyo_check_open_permission(tomoyo_domain(), &f->f_path, flags);
190 }
191
192 /*
193  * tomoyo_security_ops is a "struct security_operations" which is used for
194  * registering TOMOYO.
195  */
196 static struct security_operations tomoyo_security_ops = {
197         .name                = "tomoyo",
198         .cred_alloc_blank    = tomoyo_cred_alloc_blank,
199         .cred_prepare        = tomoyo_cred_prepare,
200         .cred_transfer       = tomoyo_cred_transfer,
201         .bprm_set_creds      = tomoyo_bprm_set_creds,
202         .bprm_check_security = tomoyo_bprm_check_security,
203         .file_fcntl          = tomoyo_file_fcntl,
204         .dentry_open         = tomoyo_dentry_open,
205         .path_truncate       = tomoyo_path_truncate,
206         .path_unlink         = tomoyo_path_unlink,
207         .path_mkdir          = tomoyo_path_mkdir,
208         .path_rmdir          = tomoyo_path_rmdir,
209         .path_symlink        = tomoyo_path_symlink,
210         .path_mknod          = tomoyo_path_mknod,
211         .path_link           = tomoyo_path_link,
212         .path_rename         = tomoyo_path_rename,
213 };
214
215 static int __init tomoyo_init(void)
216 {
217         struct cred *cred = (struct cred *) current_cred();
218
219         if (!security_module_enable(&tomoyo_security_ops))
220                 return 0;
221         /* register ourselves with the security framework */
222         if (register_security(&tomoyo_security_ops))
223                 panic("Failure registering TOMOYO Linux");
224         printk(KERN_INFO "TOMOYO Linux initialized\n");
225         cred->security = &tomoyo_kernel_domain;
226         tomoyo_realpath_init();
227         return 0;
228 }
229
230 security_initcall(tomoyo_init);