xref: /linux/security/apparmor/include/perms.h (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * AppArmor security module
4  *
5  * This file contains AppArmor basic permission sets definitions.
6  *
7  * Copyright 2017 Canonical Ltd.
8  */
9 
10 #ifndef __AA_PERM_H
11 #define __AA_PERM_H
12 
13 #include <linux/fs.h>
14 #include "label.h"
15 
16 #define AA_MAY_EXEC		MAY_EXEC
17 #define AA_MAY_WRITE		MAY_WRITE
18 #define AA_MAY_READ		MAY_READ
19 #define AA_MAY_APPEND		MAY_APPEND
20 
21 #define AA_MAY_CREATE		0x0010
22 #define AA_MAY_DELETE		0x0020
23 #define AA_MAY_OPEN		0x0040
24 #define AA_MAY_RENAME		0x0080		/* pair */
25 
26 #define AA_MAY_SETATTR		0x0100		/* meta write */
27 #define AA_MAY_GETATTR		0x0200		/* meta read */
28 #define AA_MAY_SETCRED		0x0400		/* security cred/attr */
29 #define AA_MAY_GETCRED		0x0800
30 
31 #define AA_MAY_CHMOD		0x1000		/* pair */
32 #define AA_MAY_CHOWN		0x2000		/* pair */
33 #define AA_MAY_CHGRP		0x4000		/* pair */
34 #define AA_MAY_LOCK		0x8000		/* LINK_SUBSET overlaid */
35 
36 #define AA_EXEC_MMAP		0x00010000
37 #define AA_MAY_MPROT		0x00020000	/* extend conditions */
38 #define AA_MAY_LINK		0x00040000	/* pair */
39 #define AA_MAY_SNAPSHOT		0x00080000	/* pair */
40 
41 #define AA_MAY_DELEGATE
42 #define AA_CONT_MATCH		0x08000000
43 
44 #define AA_MAY_STACK		0x10000000
45 #define AA_MAY_ONEXEC		0x20000000 /* either stack or change_profile */
46 #define AA_MAY_CHANGE_PROFILE	0x40000000
47 #define AA_MAY_CHANGEHAT	0x80000000
48 
49 #define AA_LINK_SUBSET		AA_MAY_LOCK	/* overlaid */
50 
51 #define AA_MAY_CREATE_SQPOLL   AA_MAY_CREATE
52 #define AA_MAY_OVERRIDE_CRED   AA_MAY_APPEND
53 #define AA_URING_PERM_MASK     (AA_MAY_OVERRIDE_CRED | AA_MAY_CREATE_SQPOLL)
54 
55 #define PERMS_CHRS_MASK (MAY_READ | MAY_WRITE | AA_MAY_CREATE |		\
56 			 AA_MAY_DELETE | AA_MAY_LINK | AA_MAY_LOCK |	\
57 			 AA_MAY_EXEC | AA_EXEC_MMAP | AA_MAY_APPEND)
58 
59 #define PERMS_NAMES_MASK (PERMS_CHRS_MASK | AA_MAY_OPEN | AA_MAY_RENAME |     \
60 			  AA_MAY_SETATTR | AA_MAY_GETATTR | AA_MAY_SETCRED | \
61 			  AA_MAY_GETCRED | AA_MAY_CHMOD | AA_MAY_CHOWN | \
62 			  AA_MAY_CHGRP | AA_MAY_MPROT | AA_MAY_SNAPSHOT | \
63 			  AA_MAY_STACK | AA_MAY_ONEXEC |		\
64 			  AA_MAY_CHANGE_PROFILE | AA_MAY_CHANGEHAT)
65 
66 extern const char aa_file_perm_chrs[];
67 extern const char *aa_file_perm_names[];
68 
69 struct aa_perms {
70 	u32 allow;
71 	u32 deny;	/* explicit deny, or conflict if allow also set */
72 
73 	u32 subtree;	/* allow perm on full subtree only when allow is set */
74 	u32 cond;	/* set only when ~allow and ~deny */
75 
76 	u32 kill;	/* set only when ~allow | deny */
77 	u32 complain;	/* accumulates only used when ~allow & ~deny */
78 	u32 prompt;	/* accumulates only used when ~allow & ~deny */
79 
80 	u32 audit;	/* set only when allow is set */
81 	u32 quiet;	/* set only when ~allow | deny */
82 	u32 hide;	/* set only when  ~allow | deny */
83 
84 
85 	u32 xindex;
86 	u32 tag;	/* tag string index, if present */
87 	u32 label;	/* label string index, if present */
88 };
89 
90 /*
91  * Indexes are broken into a 24 bit index and 8 bit flag.
92  * For the index to be valid there must be a value in the flag
93  */
94 #define AA_INDEX_MASK			0x00ffffff
95 #define AA_INDEX_FLAG_MASK		0xff000000
96 #define AA_INDEX_NONE			0
97 
98 #define ALL_PERMS_MASK 0xffffffff
99 extern struct aa_perms nullperms;
100 extern struct aa_perms allperms;
101 
102 /**
103  * aa_perms_accum_raw - accumulate perms with out masking off overlapping perms
104  * @accum - perms struct to accumulate into
105  * @addend - perms struct to add to @accum
106  */
107 static inline void aa_perms_accum_raw(struct aa_perms *accum,
108 				      struct aa_perms *addend)
109 {
110 	accum->deny |= addend->deny;
111 	accum->allow &= addend->allow & ~addend->deny;
112 	accum->audit |= addend->audit & addend->allow;
113 	accum->quiet &= addend->quiet & ~addend->allow;
114 	accum->kill |= addend->kill & ~addend->allow;
115 	accum->complain |= addend->complain & ~addend->allow & ~addend->deny;
116 	accum->cond |= addend->cond & ~addend->allow & ~addend->deny;
117 	accum->hide &= addend->hide & ~addend->allow;
118 	accum->prompt |= addend->prompt & ~addend->allow & ~addend->deny;
119 	accum->subtree |= addend->subtree & ~addend->deny;
120 
121 	if (!accum->xindex)
122 		accum->xindex = addend->xindex;
123 	if (!accum->tag)
124 		accum->tag = addend->tag;
125 	if (!accum->label)
126 		accum->label = addend->label;
127 }
128 
129 /**
130  * aa_perms_accum - accumulate perms, masking off overlapping perms
131  * @accum - perms struct to accumulate into
132  * @addend - perms struct to add to @accum
133  */
134 static inline void aa_perms_accum(struct aa_perms *accum,
135 				  struct aa_perms *addend)
136 {
137 	accum->deny |= addend->deny;
138 	accum->allow &= addend->allow & ~accum->deny;
139 	accum->audit |= addend->audit & accum->allow;
140 	accum->quiet &= addend->quiet & ~accum->allow;
141 	accum->kill |= addend->kill & ~accum->allow;
142 	accum->complain |= addend->complain & ~accum->allow & ~accum->deny;
143 	accum->cond |= addend->cond & ~accum->allow & ~accum->deny;
144 	accum->hide &= addend->hide & ~accum->allow;
145 	accum->prompt |= addend->prompt & ~accum->allow & ~accum->deny;
146 	accum->subtree &= addend->subtree & ~accum->deny;
147 
148 	if (!accum->xindex)
149 		accum->xindex = addend->xindex;
150 	if (!accum->tag)
151 		accum->tag = addend->tag;
152 	if (!accum->label)
153 		accum->label = addend->label;
154 }
155 
156 #define xcheck(FN1, FN2)	\
157 ({				\
158 	int e, error = FN1;	\
159 	e = FN2;		\
160 	if (e)			\
161 		error = e;	\
162 	error;			\
163 })
164 
165 
166 /*
167  * TODO: update for labels pointing to labels instead of profiles
168  * TODO: optimize the walk, currently does subwalk of L2 for each P in L1
169  * gah this doesn't allow for label compound check!!!!
170  */
171 #define xcheck_ns_profile_profile(P1, P2, FN, args...)		\
172 ({								\
173 	int ____e = 0;						\
174 	if (P1->ns == P2->ns)					\
175 		____e = FN((P1), (P2), args);			\
176 	(____e);						\
177 })
178 
179 #define xcheck_ns_profile_label(P, L, FN, args...)		\
180 ({								\
181 	struct aa_profile *__p2;				\
182 	fn_for_each((L), __p2,					\
183 		    xcheck_ns_profile_profile((P), __p2, (FN), args));	\
184 })
185 
186 #define xcheck_ns_labels(L1, L2, FN, args...)			\
187 ({								\
188 	struct aa_profile *__p1;				\
189 	fn_for_each((L1), __p1, FN(__p1, (L2), args));		\
190 })
191 
192 /* Do the cross check but applying FN at the profiles level */
193 #define xcheck_labels_profiles(L1, L2, FN, args...)		\
194 	xcheck_ns_labels((L1), (L2), xcheck_ns_profile_label, (FN), args)
195 
196 #define xcheck_labels(L1, L2, P, FN1, FN2)			\
197 	xcheck(fn_for_each((L1), (P), (FN1)), fn_for_each((L2), (P), (FN2)))
198 
199 
200 extern struct aa_perms default_perms;
201 
202 
203 void aa_perm_mask_to_str(char *str, size_t str_size, const char *chrs,
204 			 u32 mask);
205 void aa_audit_perm_names(struct audit_buffer *ab, const char * const *names,
206 			 u32 mask);
207 void aa_audit_perm_mask(struct audit_buffer *ab, u32 mask, const char *chrs,
208 			u32 chrsmask, const char * const *names, u32 namesmask);
209 void aa_apply_modes_to_perms(struct aa_profile *profile,
210 			     struct aa_perms *perms);
211 void aa_perms_accum(struct aa_perms *accum, struct aa_perms *addend);
212 void aa_perms_accum_raw(struct aa_perms *accum, struct aa_perms *addend);
213 void aa_profile_match_label(struct aa_profile *profile,
214 			    struct aa_ruleset *rules, struct aa_label *label,
215 			    int type, u32 request, struct aa_perms *perms);
216 int aa_profile_label_perm(struct aa_profile *profile, struct aa_profile *target,
217 			  u32 request, int type, u32 *deny,
218 			  struct apparmor_audit_data *ad);
219 int aa_check_perms(struct aa_profile *profile, struct aa_perms *perms,
220 		   u32 request, struct apparmor_audit_data *ad,
221 		   void (*cb)(struct audit_buffer *, void *));
222 #endif /* __AA_PERM_H */
223