1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * AppArmor security module
4 *
5 * This file contains AppArmor policy loading interface function definitions.
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11 #ifndef __POLICY_INTERFACE_H
12 #define __POLICY_INTERFACE_H
13
14 #include <linux/list.h>
15 #include <linux/kref.h>
16 #include <linux/dcache.h>
17 #include <linux/workqueue.h>
18
19 #include "lib.h"
20
21 struct aa_load_ent {
22 struct list_head list;
23 struct aa_profile *new;
24 struct aa_profile *old;
25 struct aa_profile *rename;
26 const char *ns_name;
27 };
28
29 void aa_load_ent_free(struct aa_load_ent *ent);
30 struct aa_load_ent *aa_load_ent_alloc(void);
31
32 #define PACKED_FLAG_HAT 1
33 #define PACKED_FLAG_DEBUG1 2
34 #define PACKED_FLAG_DEBUG2 4
35
36 #define PACKED_MODE_ENFORCE 0
37 #define PACKED_MODE_COMPLAIN 1
38 #define PACKED_MODE_KILL 2
39 #define PACKED_MODE_UNCONFINED 3
40 #define PACKED_MODE_USER 4
41
42 struct aa_ns;
43
44 enum {
45 AAFS_LOADDATA_ABI = 0,
46 AAFS_LOADDATA_REVISION,
47 AAFS_LOADDATA_HASH,
48 AAFS_LOADDATA_DATA,
49 AAFS_LOADDATA_COMPRESSED_SIZE,
50 AAFS_LOADDATA_DIR, /* must be last actual entry */
51 AAFS_LOADDATA_NDENTS /* count of entries */
52 };
53
54 /*
55 * The AppArmor interface treats data as a type byte followed by the
56 * actual data. The interface has the notion of a named entry
57 * which has a name (AA_NAME typecode followed by name string) followed by
58 * the entries typecode and data. Named types allow for optional
59 * elements and extensions to be added and tested for without breaking
60 * backwards compatibility.
61 */
62
63 enum aa_code {
64 AA_U8,
65 AA_U16,
66 AA_U32,
67 AA_U64,
68 AA_NAME, /* same as string except it is items name */
69 AA_STRING,
70 AA_BLOB,
71 AA_STRUCT,
72 AA_STRUCTEND,
73 AA_LIST,
74 AA_LISTEND,
75 AA_ARRAY,
76 AA_ARRAYEND,
77 };
78
79 /*
80 * aa_ext is the read of the buffer containing the serialized profile. The
81 * data is copied into a kernel buffer in apparmorfs and then handed off to
82 * the unpack routines.
83 */
84 struct aa_ext {
85 void *start;
86 void *end;
87 void *pos; /* pointer to current position in the buffer */
88 u32 version;
89 };
90
91 /* struct aa_loaddata - buffer of policy raw_data set
92 * @count: inode/filesystem refcount - use aa_get_i_loaddata()
93 * @pcount: profile refcount - use aa_get_profile_loaddata()
94 * @list: list the loaddata is on
95 * @work: used to do a delayed cleanup
96 * @dents: refs to dents created in aafs
97 * @ns: the namespace this loaddata was loaded into
98 * @name:
99 * @size: the size of the data that was loaded
100 * @compressed_size: the size of the data when it is compressed
101 * @revision: unique revision count that this data was loaded as
102 * @abi: the abi number the loaddata uses
103 * @hash: a hash of the loaddata, used to help dedup data
104 *
105 * There is no loaddata ref for being on ns->rawdata_list, so
106 * @ns->lock must be held when walking the list. Dentries and
107 * inode opens hold refs on @count; profiles hold refs on @pcount.
108 * When the last @pcount drops, do_ploaddata_rmfs() removes the
109 * fs entries and drops the associated @count ref.
110 */
111 struct aa_loaddata {
112 struct aa_common_ref count;
113 struct kref pcount;
114 struct list_head list;
115 struct work_struct work;
116 struct dentry *dents[AAFS_LOADDATA_NDENTS];
117 struct aa_ns *ns;
118 char *name;
119 size_t size; /* the original size of the payload */
120 size_t compressed_size; /* the compressed size of the payload */
121 long revision; /* the ns policy revision this caused */
122 int abi;
123 unsigned char *hash;
124
125 /* Pointer to payload. If @compressed_size > 0, then this is the
126 * compressed version of the payload, else it is the uncompressed
127 * version (with the size indicated by @size).
128 */
129 char *data;
130 };
131
132 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, const char **ns,
133 char *compressed_data, size_t compressed_size);
134
135 /**
136 * aa_get_i_loaddata - get a reference count from a counted data reference
137 * @data: reference to get a count on
138 *
139 * Returns: pointer to reference
140 * Requires: @data to have a valid reference count on it. It is a bug
141 * if the race to reap can be encountered when it is used.
142 */
143 static inline struct aa_loaddata *
aa_get_i_loaddata(struct aa_loaddata * data)144 aa_get_i_loaddata(struct aa_loaddata *data)
145 {
146
147 if (data)
148 kref_get(&(data->count.count));
149 return data;
150 }
151
152
153 /**
154 * aa_get_profile_loaddata - get a profile reference count on loaddata
155 * @data: reference to get a count on
156 *
157 * Returns: pointer to reference
158 * Requires: @data to have a valid reference count on it.
159 */
160 static inline struct aa_loaddata *
aa_get_profile_loaddata(struct aa_loaddata * data)161 aa_get_profile_loaddata(struct aa_loaddata *data)
162 {
163 if (data)
164 kref_get(&(data->pcount));
165 return data;
166 }
167
168 /**
169 * aa_get_profile_loaddata_not0 - get a profile reference count if not zero
170 * @data: reference to get a count on
171 *
172 * Like aa_get_profile_loaddata(), but safe to call on an entry that may
173 * be on a list (e.g. ns->rawdata_list) where the last pcount has already
174 * dropped and the deferred cleanup has not yet run.
175 *
176 * Returns: pointer to reference, or %NULL if @data is NULL or its
177 * profile refcount has already reached zero.
178 */
179 static inline struct aa_loaddata *
aa_get_profile_loaddata_not0(struct aa_loaddata * data)180 aa_get_profile_loaddata_not0(struct aa_loaddata *data)
181 {
182 if (data && kref_get_unless_zero(&data->pcount))
183 return data;
184 return NULL;
185 }
186
187 void __aa_loaddata_update(struct aa_loaddata *data, long revision);
188 bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r);
189 void aa_loaddata_kref(struct kref *kref);
190 void aa_ploaddata_kref(struct kref *kref);
191 struct aa_loaddata *aa_loaddata_alloc(size_t size);
aa_put_i_loaddata(struct aa_loaddata * data)192 static inline void aa_put_i_loaddata(struct aa_loaddata *data)
193 {
194 if (data)
195 kref_put(&data->count.count, aa_loaddata_kref);
196 }
197
aa_put_profile_loaddata(struct aa_loaddata * data)198 static inline void aa_put_profile_loaddata(struct aa_loaddata *data)
199 {
200 if (data)
201 kref_put(&data->pcount, aa_ploaddata_kref);
202 }
203
204 #if IS_ENABLED(CONFIG_KUNIT)
205 bool aa_inbounds(struct aa_ext *e, size_t size);
206 size_t aa_unpack_u16_chunk(struct aa_ext *e, char **chunk);
207 bool aa_unpack_X(struct aa_ext *e, enum aa_code code);
208 bool aa_unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name);
209 bool aa_unpack_u32(struct aa_ext *e, u32 *data, const char *name);
210 bool aa_unpack_u64(struct aa_ext *e, u64 *data, const char *name);
211 bool aa_unpack_array(struct aa_ext *e, const char *name, u16 *size);
212 size_t aa_unpack_blob(struct aa_ext *e, char **blob, const char *name);
213 int aa_unpack_str(struct aa_ext *e, const char **string, const char *name);
214 int aa_unpack_strdup(struct aa_ext *e, char **string, const char *name);
215 #endif
216
217 #endif /* __POLICY_INTERFACE_H */
218