Loading...
1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor file mediation function definitions.
5 *
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
8 *
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
12 * License.
13 */
14
15#ifndef __AA_FILE_H
16#define __AA_FILE_H
17
18#include <linux/spinlock.h>
19
20#include "domain.h"
21#include "match.h"
22#include "perms.h"
23
24struct aa_profile;
25struct path;
26
27#define mask_mode_t(X) (X & (MAY_EXEC | MAY_WRITE | MAY_READ | MAY_APPEND))
28
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)
34
35#define file_ctx(X) ((struct aa_file_ctx *)(X)->f_security)
36
37/* struct aa_file_ctx - the AppArmor context the file was opened in
38 * @lock: lock to update the ctx
39 * @label: label currently cached on the ctx
40 * @perms: the permission the file was opened with
41 */
42struct aa_file_ctx {
43 spinlock_t lock;
44 struct aa_label __rcu *label;
45 u32 allow;
46};
47
48/**
49 * aa_alloc_file_ctx - allocate file_ctx
50 * @label: initial label of task creating the file
51 * @gfp: gfp flags for allocation
52 *
53 * Returns: file_ctx or NULL on failure
54 */
55static inline struct aa_file_ctx *aa_alloc_file_ctx(struct aa_label *label,
56 gfp_t gfp)
57{
58 struct aa_file_ctx *ctx;
59
60 ctx = kzalloc(sizeof(struct aa_file_ctx), gfp);
61 if (ctx) {
62 spin_lock_init(&ctx->lock);
63 rcu_assign_pointer(ctx->label, aa_get_label(label));
64 }
65 return ctx;
66}
67
68/**
69 * aa_free_file_ctx - free a file_ctx
70 * @ctx: file_ctx to free (MAYBE_NULL)
71 */
72static inline void aa_free_file_ctx(struct aa_file_ctx *ctx)
73{
74 if (ctx) {
75 aa_put_label(rcu_access_pointer(ctx->label));
76 kzfree(ctx);
77 }
78}
79
80static inline struct aa_label *aa_get_file_label(struct aa_file_ctx *ctx)
81{
82 return aa_get_label_rcu(&ctx->label);
83}
84
85/*
86 * The xindex is broken into 3 parts
87 * - index - an index into either the exec name table or the variable table
88 * - exec type - which determines how the executable name and index are used
89 * - flags - which modify how the destination name is applied
90 */
91#define AA_X_INDEX_MASK 0x03ff
92
93#define AA_X_TYPE_MASK 0x0c00
94#define AA_X_TYPE_SHIFT 10
95#define AA_X_NONE 0x0000
96#define AA_X_NAME 0x0400 /* use executable name px */
97#define AA_X_TABLE 0x0800 /* use a specified name ->n# */
98
99#define AA_X_UNSAFE 0x1000
100#define AA_X_CHILD 0x2000 /* make >AA_X_NONE apply to children */
101#define AA_X_INHERIT 0x4000
102#define AA_X_UNCONFINED 0x8000
103
104/* need to make conditional which ones are being set */
105struct path_cond {
106 kuid_t uid;
107 umode_t mode;
108};
109
110#define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
111
112/* FIXME: split perms from dfa and match this to description
113 * also add delegation info.
114 */
115static inline u16 dfa_map_xindex(u16 mask)
116{
117 u16 old_index = (mask >> 10) & 0xf;
118 u16 index = 0;
119
120 if (mask & 0x100)
121 index |= AA_X_UNSAFE;
122 if (mask & 0x200)
123 index |= AA_X_INHERIT;
124 if (mask & 0x80)
125 index |= AA_X_UNCONFINED;
126
127 if (old_index == 1) {
128 index |= AA_X_UNCONFINED;
129 } else if (old_index == 2) {
130 index |= AA_X_NAME;
131 } else if (old_index == 3) {
132 index |= AA_X_NAME | AA_X_CHILD;
133 } else if (old_index) {
134 index |= AA_X_TABLE;
135 index |= old_index - 4;
136 }
137
138 return index;
139}
140
141/*
142 * map old dfa inline permissions to new format
143 */
144#define dfa_user_allow(dfa, state) (((ACCEPT_TABLE(dfa)[state]) & 0x7f) | \
145 ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
146#define dfa_user_audit(dfa, state) ((ACCEPT_TABLE2(dfa)[state]) & 0x7f)
147#define dfa_user_quiet(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 7) & 0x7f)
148#define dfa_user_xindex(dfa, state) \
149 (dfa_map_xindex(ACCEPT_TABLE(dfa)[state] & 0x3fff))
150
151#define dfa_other_allow(dfa, state) ((((ACCEPT_TABLE(dfa)[state]) >> 14) & \
152 0x7f) | \
153 ((ACCEPT_TABLE(dfa)[state]) & 0x80000000))
154#define dfa_other_audit(dfa, state) (((ACCEPT_TABLE2(dfa)[state]) >> 14) & 0x7f)
155#define dfa_other_quiet(dfa, state) \
156 ((((ACCEPT_TABLE2(dfa)[state]) >> 7) >> 14) & 0x7f)
157#define dfa_other_xindex(dfa, state) \
158 dfa_map_xindex((ACCEPT_TABLE(dfa)[state] >> 14) & 0x3fff)
159
160int aa_audit_file(struct aa_profile *profile, struct aa_perms *perms,
161 const char *op, u32 request, const char *name,
162 const char *target, struct aa_label *tlabel, kuid_t ouid,
163 const char *info, int error);
164
165/**
166 * struct aa_file_rules - components used for file rule permissions
167 * @dfa: dfa to match path names and conditionals against
168 * @perms: permission table indexed by the matched state accept entry of @dfa
169 * @trans: transition table for indexed by named x transitions
170 *
171 * File permission are determined by matching a path against @dfa and then
172 * then using the value of the accept entry for the matching state as
173 * an index into @perms. If a named exec transition is required it is
174 * looked up in the transition table.
175 */
176struct aa_file_rules {
177 unsigned int start;
178 struct aa_dfa *dfa;
179 /* struct perms perms; */
180 struct aa_domain trans;
181 /* TODO: add delegate table */
182};
183
184struct aa_perms aa_compute_fperms(struct aa_dfa *dfa, unsigned int state,
185 struct path_cond *cond);
186unsigned int aa_str_perms(struct aa_dfa *dfa, unsigned int start,
187 const char *name, struct path_cond *cond,
188 struct aa_perms *perms);
189
190int __aa_path_perm(const char *op, struct aa_profile *profile,
191 const char *name, u32 request, struct path_cond *cond,
192 int flags, struct aa_perms *perms);
193int aa_path_perm(const char *op, struct aa_label *label,
194 const struct path *path, int flags, u32 request,
195 struct path_cond *cond);
196
197int aa_path_link(struct aa_label *label, struct dentry *old_dentry,
198 const struct path *new_dir, struct dentry *new_dentry);
199
200int aa_file_perm(const char *op, struct aa_label *label, struct file *file,
201 u32 request);
202
203void aa_inherit_files(const struct cred *cred, struct files_struct *files);
204
205static inline void aa_free_file_rules(struct aa_file_rules *rules)
206{
207 aa_put_dfa(rules->dfa);
208 aa_free_domain_entries(&rules->trans);
209}
210
211/**
212 * aa_map_file_perms - map file flags to AppArmor permissions
213 * @file: open file to map flags to AppArmor permissions
214 *
215 * Returns: apparmor permission set for the file
216 */
217static inline u32 aa_map_file_to_perms(struct file *file)
218{
219 int flags = file->f_flags;
220 u32 perms = 0;
221
222 if (file->f_mode & FMODE_WRITE)
223 perms |= MAY_WRITE;
224 if (file->f_mode & FMODE_READ)
225 perms |= MAY_READ;
226
227 if ((flags & O_APPEND) && (perms & MAY_WRITE))
228 perms = (perms & ~MAY_WRITE) | MAY_APPEND;
229 /* trunc implies write permission */
230 if (flags & O_TRUNC)
231 perms |= MAY_WRITE;
232 if (flags & O_CREAT)
233 perms |= AA_MAY_CREATE;
234
235 return perms;
236}
237
238#endif /* __AA_FILE_H */
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor file mediation function definitions.
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11#ifndef __AA_FILE_H
12#define __AA_FILE_H
13
14#include <linux/spinlock.h>
15
16#include "domain.h"
17#include "match.h"
18#include "perms.h"
19
20struct aa_policydb;
21struct aa_profile;
22struct path;
23
24#define mask_mode_t(X) (X & (MAY_EXEC | MAY_WRITE | MAY_READ | MAY_APPEND))
25
26#define AA_AUDIT_FILE_MASK (MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
27 AA_MAY_CREATE | AA_MAY_DELETE | \
28 AA_MAY_GETATTR | AA_MAY_SETATTR | \
29 AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
30 AA_EXEC_MMAP | AA_MAY_LINK)
31
32static inline struct aa_file_ctx *file_ctx(struct file *file)
33{
34 return file->f_security + apparmor_blob_sizes.lbs_file;
35}
36
37/* struct aa_file_ctx - the AppArmor context the file was opened in
38 * @lock: lock to update the ctx
39 * @label: label currently cached on the ctx
40 * @perms: the permission the file was opened with
41 */
42struct aa_file_ctx {
43 spinlock_t lock;
44 struct aa_label __rcu *label;
45 u32 allow;
46};
47
48/*
49 * The xindex is broken into 3 parts
50 * - index - an index into either the exec name table or the variable table
51 * - exec type - which determines how the executable name and index are used
52 * - flags - which modify how the destination name is applied
53 */
54#define AA_X_INDEX_MASK AA_INDEX_MASK
55
56#define AA_X_TYPE_MASK 0x0c000000
57#define AA_X_NONE AA_INDEX_NONE
58#define AA_X_NAME 0x04000000 /* use executable name px */
59#define AA_X_TABLE 0x08000000 /* use a specified name ->n# */
60
61#define AA_X_UNSAFE 0x10000000
62#define AA_X_CHILD 0x20000000
63#define AA_X_INHERIT 0x40000000
64#define AA_X_UNCONFINED 0x80000000
65
66/* need to make conditional which ones are being set */
67struct path_cond {
68 kuid_t uid;
69 umode_t mode;
70};
71
72#define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
73
74int aa_audit_file(const struct cred *cred,
75 struct aa_profile *profile, struct aa_perms *perms,
76 const char *op, u32 request, const char *name,
77 const char *target, struct aa_label *tlabel, kuid_t ouid,
78 const char *info, int error);
79
80struct aa_perms *aa_lookup_fperms(struct aa_policydb *file_rules,
81 aa_state_t state, struct path_cond *cond);
82aa_state_t aa_str_perms(struct aa_policydb *file_rules, aa_state_t start,
83 const char *name, struct path_cond *cond,
84 struct aa_perms *perms);
85
86int aa_path_perm(const char *op, const struct cred *subj_cred,
87 struct aa_label *label, const struct path *path,
88 int flags, u32 request, struct path_cond *cond);
89
90int aa_path_link(const struct cred *subj_cred, struct aa_label *label,
91 struct dentry *old_dentry, const struct path *new_dir,
92 struct dentry *new_dentry);
93
94int aa_file_perm(const char *op, const struct cred *subj_cred,
95 struct aa_label *label, struct file *file,
96 u32 request, bool in_atomic);
97
98void aa_inherit_files(const struct cred *cred, struct files_struct *files);
99
100
101/**
102 * aa_map_file_perms - map file flags to AppArmor permissions
103 * @file: open file to map flags to AppArmor permissions
104 *
105 * Returns: apparmor permission set for the file
106 */
107static inline u32 aa_map_file_to_perms(struct file *file)
108{
109 int flags = file->f_flags;
110 u32 perms = 0;
111
112 if (file->f_mode & FMODE_WRITE)
113 perms |= MAY_WRITE;
114 if (file->f_mode & FMODE_READ)
115 perms |= MAY_READ;
116
117 if ((flags & O_APPEND) && (perms & MAY_WRITE))
118 perms = (perms & ~MAY_WRITE) | MAY_APPEND;
119 /* trunc implies write permission */
120 if (flags & O_TRUNC)
121 perms |= MAY_WRITE;
122 if (flags & O_CREAT)
123 perms |= AA_MAY_CREATE;
124
125 return perms;
126}
127
128#endif /* __AA_FILE_H */