2 * AppArmor security module
4 * This file contains AppArmor file mediation function definitions.
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
18 #include <linux/spinlock.h>
27 #define mask_mode_t(X) (X & (MAY_EXEC | MAY_WRITE | MAY_READ | MAY_APPEND))
29 #define AA_AUDIT_FILE_MASK (MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
30 AA_MAY_CREATE | AA_MAY_DELETE | \
31 AA_MAY_GETATTR | AA_MAY_SETATTR | \
32 AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
33 AA_EXEC_MMAP | AA_MAY_LINK)
35 static inline struct aa_file_ctx *file_ctx(struct file *file)
37 return file->f_security + apparmor_blob_sizes.lbs_file;
40 /* struct aa_file_ctx - the AppArmor context the file was opened in
41 * @lock: lock to update the ctx
42 * @label: label currently cached on the ctx
43 * @perms: the permission the file was opened with
47 struct aa_label __rcu *label;
52 * aa_alloc_file_ctx - allocate file_ctx
53 * @label: initial label of task creating the file
54 * @gfp: gfp flags for allocation
56 * Returns: file_ctx or NULL on failure
58 static inline struct aa_file_ctx *aa_alloc_file_ctx(struct aa_label *label,
61 struct aa_file_ctx *ctx;
63 ctx = kzalloc(sizeof(struct aa_file_ctx), gfp);
65 spin_lock_init(&ctx->lock);
66 rcu_assign_pointer(ctx->label, aa_get_label(label));
72 * aa_free_file_ctx - free a file_ctx
73 * @ctx: file_ctx to free (MAYBE_NULL)
75 static inline void aa_free_file_ctx(struct aa_file_ctx *ctx)
78 aa_put_label(rcu_access_pointer(ctx->label));
83 static inline struct aa_label *aa_get_file_label(struct aa_file_ctx *ctx)
85 return aa_get_label_rcu(&ctx->label);
89 * The xindex is broken into 3 parts
90 * - index - an index into either the exec name table or the variable table
91 * - exec type - which determines how the executable name and index are used
92 * - flags - which modify how the destination name is applied
94 #define AA_X_INDEX_MASK 0x03ff
96 #define AA_X_TYPE_MASK 0x0c00
97 #define AA_X_TYPE_SHIFT 10
98 #define AA_X_NONE 0x0000
99 #define AA_X_NAME 0x0400 /* use executable name px */
100 #define AA_X_TABLE 0x0800 /* use a specified name ->n# */
102 #define AA_X_UNSAFE 0x1000
103 #define AA_X_CHILD 0x2000 /* make >AA_X_NONE apply to children */
104 #define AA_X_INHERIT 0x4000
105 #define AA_X_UNCONFINED 0x8000
107 /* need to make conditional which ones are being set */
113 #define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
115 /* FIXME: split perms from dfa and match this to description
116 * also add delegation info.
118 static inline u16 dfa_map_xindex(u16 mask)
120 u16 old_index = (mask >> 10) & 0xf;
124 index |= AA_X_UNSAFE;
126 index |= AA_X_INHERIT;
128 index |= AA_X_UNCONFINED;
130 if (old_index == 1) {
131 index |= AA_X_UNCONFINED;
132 } else if (old_index == 2) {
134 } else if (old_index == 3) {
135 index |= AA_X_NAME | AA_X_CHILD;
136 } else if (old_index) {
138 index |= old_index - 4;
145 * map old dfa inline permissions to new format
147 #define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) | \
148 ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
149 #define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
150 #define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
151 #define dfa_user_xindex(dfa, state) \
152 (dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))
154 #define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
156 ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
157 #define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
158 #define dfa_other_quiet(dfa, state) \
159 ((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
160 #define dfa_other_xindex(dfa, state) \
161 dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)
163 int aa_audit_file(struct aa_profile *profile, struct aa_perms *perms,
164 const char *op, u32 request, const char *name,
165 const char *target, struct aa_label *tlabel, kuid_t ouid,
166 const char *info, int error);
169 * struct aa_file_rules - components used for file rule permissions
170 * @dfa: dfa to match path names and conditionals against
171 * @perms: permission table indexed by the matched state accept entry of @dfa
172 * @trans: transition table for indexed by named x transitions
174 * File permission are determined by matching a path against @dfa and then
175 * then using the value of the accept entry for the matching state as
176 * an index into @perms. If a named exec transition is required it is
177 * looked up in the transition table.
179 struct aa_file_rules {
182 /* struct perms perms; */
183 struct aa_domain trans;
184 /* TODO: add delegate table */
187 struct aa_perms aa_compute_fperms(struct aa_dfa *dfa, unsigned int state,
188 struct path_cond *cond);
189 unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
190 const char *name, struct path_cond *cond,
191 struct aa_perms *perms);
193 int __aa_path_perm(const char *op, struct aa_profile *profile,
194 const char *name, u32 request, struct path_cond *cond,
195 int flags, struct aa_perms *perms);
196 int aa_path_perm(const char *op, struct aa_label *label,
197 const struct path *path, int flags, u32 request,
198 struct path_cond *cond);
200 int aa_path_link(struct aa_label *label, struct dentry *old_dentry,
201 const struct path *new_dir, struct dentry *new_dentry);
203 int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
206 void aa_inherit_files(const struct cred *cred, struct files_struct *files);
208 static inline void aa_free_file_rules(struct aa_file_rules *rules)
210 aa_put_dfa(rules->dfa);
211 aa_free_domain_entries(&rules->trans);
215 * aa_map_file_perms - map file flags to AppArmor permissions
216 * @file: open file to map flags to AppArmor permissions
218 * Returns: apparmor permission set for the file
220 static inline u32 aa_map_file_to_perms(struct file *file)
222 int flags = file->f_flags;
225 if (file->f_mode & FMODE_WRITE)
227 if (file->f_mode & FMODE_READ)
230 if ((flags & O_APPEND) && (perms & MAY_WRITE))
231 perms = (perms & ~MAY_WRITE) | MAY_APPEND;
232 /* trunc implies write permission */
236 perms |= AA_MAY_CREATE;
241 #endif /* __AA_FILE_H */