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1/*
2 * A security context is a set of security attributes
3 * associated with each subject and object controlled
4 * by the security policy. Security contexts are
5 * externally represented as variable-length strings
6 * that can be interpreted by a user or application
7 * with an understanding of the security policy.
8 * Internally, the security server uses a simple
9 * structure. This structure is private to the
10 * security server and can be changed without affecting
11 * clients of the security server.
12 *
13 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
14 */
15#ifndef _SS_CONTEXT_H_
16#define _SS_CONTEXT_H_
17
18#include "ebitmap.h"
19#include "mls_types.h"
20#include "security.h"
21
22/*
23 * A security context consists of an authenticated user
24 * identity, a role, a type and a MLS range.
25 */
26struct context {
27 u32 user;
28 u32 role;
29 u32 type;
30 u32 len; /* length of string in bytes */
31 struct mls_range range;
32 char *str; /* string representation if context cannot be mapped. */
33};
34
35static inline void mls_context_init(struct context *c)
36{
37 memset(&c->range, 0, sizeof(c->range));
38}
39
40static inline int mls_context_cpy(struct context *dst, struct context *src)
41{
42 int rc;
43
44 dst->range.level[0].sens = src->range.level[0].sens;
45 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
46 if (rc)
47 goto out;
48
49 dst->range.level[1].sens = src->range.level[1].sens;
50 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
51 if (rc)
52 ebitmap_destroy(&dst->range.level[0].cat);
53out:
54 return rc;
55}
56
57/*
58 * Sets both levels in the MLS range of 'dst' to the low level of 'src'.
59 */
60static inline int mls_context_cpy_low(struct context *dst, struct context *src)
61{
62 int rc;
63
64 dst->range.level[0].sens = src->range.level[0].sens;
65 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
66 if (rc)
67 goto out;
68
69 dst->range.level[1].sens = src->range.level[0].sens;
70 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[0].cat);
71 if (rc)
72 ebitmap_destroy(&dst->range.level[0].cat);
73out:
74 return rc;
75}
76
77/*
78 * Sets both levels in the MLS range of 'dst' to the high level of 'src'.
79 */
80static inline int mls_context_cpy_high(struct context *dst, struct context *src)
81{
82 int rc;
83
84 dst->range.level[0].sens = src->range.level[1].sens;
85 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[1].cat);
86 if (rc)
87 goto out;
88
89 dst->range.level[1].sens = src->range.level[1].sens;
90 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
91 if (rc)
92 ebitmap_destroy(&dst->range.level[0].cat);
93out:
94 return rc;
95}
96
97static inline int mls_context_cmp(struct context *c1, struct context *c2)
98{
99 return ((c1->range.level[0].sens == c2->range.level[0].sens) &&
100 ebitmap_cmp(&c1->range.level[0].cat, &c2->range.level[0].cat) &&
101 (c1->range.level[1].sens == c2->range.level[1].sens) &&
102 ebitmap_cmp(&c1->range.level[1].cat, &c2->range.level[1].cat));
103}
104
105static inline void mls_context_destroy(struct context *c)
106{
107 ebitmap_destroy(&c->range.level[0].cat);
108 ebitmap_destroy(&c->range.level[1].cat);
109 mls_context_init(c);
110}
111
112static inline void context_init(struct context *c)
113{
114 memset(c, 0, sizeof(*c));
115}
116
117static inline int context_cpy(struct context *dst, struct context *src)
118{
119 int rc;
120
121 dst->user = src->user;
122 dst->role = src->role;
123 dst->type = src->type;
124 if (src->str) {
125 dst->str = kstrdup(src->str, GFP_ATOMIC);
126 if (!dst->str)
127 return -ENOMEM;
128 dst->len = src->len;
129 } else {
130 dst->str = NULL;
131 dst->len = 0;
132 }
133 rc = mls_context_cpy(dst, src);
134 if (rc) {
135 kfree(dst->str);
136 return rc;
137 }
138 return 0;
139}
140
141static inline void context_destroy(struct context *c)
142{
143 c->user = c->role = c->type = 0;
144 kfree(c->str);
145 c->str = NULL;
146 c->len = 0;
147 mls_context_destroy(c);
148}
149
150static inline int context_cmp(struct context *c1, struct context *c2)
151{
152 if (c1->len && c2->len)
153 return (c1->len == c2->len && !strcmp(c1->str, c2->str));
154 if (c1->len || c2->len)
155 return 0;
156 return ((c1->user == c2->user) &&
157 (c1->role == c2->role) &&
158 (c1->type == c2->type) &&
159 mls_context_cmp(c1, c2));
160}
161
162#endif /* _SS_CONTEXT_H_ */
163
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * A security context is a set of security attributes
4 * associated with each subject and object controlled
5 * by the security policy. Security contexts are
6 * externally represented as variable-length strings
7 * that can be interpreted by a user or application
8 * with an understanding of the security policy.
9 * Internally, the security server uses a simple
10 * structure. This structure is private to the
11 * security server and can be changed without affecting
12 * clients of the security server.
13 *
14 * Author : Stephen Smalley, <sds@tycho.nsa.gov>
15 */
16#ifndef _SS_CONTEXT_H_
17#define _SS_CONTEXT_H_
18
19#include "ebitmap.h"
20#include "mls_types.h"
21#include "security.h"
22
23/*
24 * A security context consists of an authenticated user
25 * identity, a role, a type and a MLS range.
26 */
27struct context {
28 u32 user;
29 u32 role;
30 u32 type;
31 u32 len; /* length of string in bytes */
32 struct mls_range range;
33 char *str; /* string representation if context cannot be mapped. */
34};
35
36static inline void mls_context_init(struct context *c)
37{
38 memset(&c->range, 0, sizeof(c->range));
39}
40
41static inline int mls_context_cpy(struct context *dst, struct context *src)
42{
43 int rc;
44
45 dst->range.level[0].sens = src->range.level[0].sens;
46 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
47 if (rc)
48 goto out;
49
50 dst->range.level[1].sens = src->range.level[1].sens;
51 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
52 if (rc)
53 ebitmap_destroy(&dst->range.level[0].cat);
54out:
55 return rc;
56}
57
58/*
59 * Sets both levels in the MLS range of 'dst' to the low level of 'src'.
60 */
61static inline int mls_context_cpy_low(struct context *dst, struct context *src)
62{
63 int rc;
64
65 dst->range.level[0].sens = src->range.level[0].sens;
66 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
67 if (rc)
68 goto out;
69
70 dst->range.level[1].sens = src->range.level[0].sens;
71 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[0].cat);
72 if (rc)
73 ebitmap_destroy(&dst->range.level[0].cat);
74out:
75 return rc;
76}
77
78/*
79 * Sets both levels in the MLS range of 'dst' to the high level of 'src'.
80 */
81static inline int mls_context_cpy_high(struct context *dst, struct context *src)
82{
83 int rc;
84
85 dst->range.level[0].sens = src->range.level[1].sens;
86 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[1].cat);
87 if (rc)
88 goto out;
89
90 dst->range.level[1].sens = src->range.level[1].sens;
91 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
92 if (rc)
93 ebitmap_destroy(&dst->range.level[0].cat);
94out:
95 return rc;
96}
97
98
99static inline int mls_context_glblub(struct context *dst,
100 struct context *c1, struct context *c2)
101{
102 struct mls_range *dr = &dst->range, *r1 = &c1->range, *r2 = &c2->range;
103 int rc = 0;
104
105 if (r1->level[1].sens < r2->level[0].sens ||
106 r2->level[1].sens < r1->level[0].sens)
107 /* These ranges have no common sensitivities */
108 return -EINVAL;
109
110 /* Take the greatest of the low */
111 dr->level[0].sens = max(r1->level[0].sens, r2->level[0].sens);
112
113 /* Take the least of the high */
114 dr->level[1].sens = min(r1->level[1].sens, r2->level[1].sens);
115
116 rc = ebitmap_and(&dr->level[0].cat,
117 &r1->level[0].cat, &r2->level[0].cat);
118 if (rc)
119 goto out;
120
121 rc = ebitmap_and(&dr->level[1].cat,
122 &r1->level[1].cat, &r2->level[1].cat);
123 if (rc)
124 goto out;
125
126out:
127 return rc;
128}
129
130static inline int mls_context_cmp(struct context *c1, struct context *c2)
131{
132 return ((c1->range.level[0].sens == c2->range.level[0].sens) &&
133 ebitmap_cmp(&c1->range.level[0].cat, &c2->range.level[0].cat) &&
134 (c1->range.level[1].sens == c2->range.level[1].sens) &&
135 ebitmap_cmp(&c1->range.level[1].cat, &c2->range.level[1].cat));
136}
137
138static inline void mls_context_destroy(struct context *c)
139{
140 ebitmap_destroy(&c->range.level[0].cat);
141 ebitmap_destroy(&c->range.level[1].cat);
142 mls_context_init(c);
143}
144
145static inline void context_init(struct context *c)
146{
147 memset(c, 0, sizeof(*c));
148}
149
150static inline int context_cpy(struct context *dst, struct context *src)
151{
152 int rc;
153
154 dst->user = src->user;
155 dst->role = src->role;
156 dst->type = src->type;
157 if (src->str) {
158 dst->str = kstrdup(src->str, GFP_ATOMIC);
159 if (!dst->str)
160 return -ENOMEM;
161 dst->len = src->len;
162 } else {
163 dst->str = NULL;
164 dst->len = 0;
165 }
166 rc = mls_context_cpy(dst, src);
167 if (rc) {
168 kfree(dst->str);
169 return rc;
170 }
171 return 0;
172}
173
174static inline void context_destroy(struct context *c)
175{
176 c->user = c->role = c->type = 0;
177 kfree(c->str);
178 c->str = NULL;
179 c->len = 0;
180 mls_context_destroy(c);
181}
182
183static inline int context_cmp(struct context *c1, struct context *c2)
184{
185 if (c1->len && c2->len)
186 return (c1->len == c2->len && !strcmp(c1->str, c2->str));
187 if (c1->len || c2->len)
188 return 0;
189 return ((c1->user == c2->user) &&
190 (c1->role == c2->role) &&
191 (c1->type == c2->type) &&
192 mls_context_cmp(c1, c2));
193}
194
195u32 context_compute_hash(const struct context *c);
196
197#endif /* _SS_CONTEXT_H_ */
198