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
16 /* Ported to Xen 3.0, George Coker, <gscoker@alpha.ncsc.mil> */
17
18 #ifndef _SS_CONTEXT_H_
19 #define _SS_CONTEXT_H_
20
21 #include "ebitmap.h"
22 #include "mls_types.h"
23 #include "security.h"
24
25 /*
26 * A security context consists of an authenticated user
27 * identity, a role, a type and a MLS range.
28 */
29 struct context {
30 u32 user;
31 u32 role;
32 u32 type;
33 struct mls_range range;
34 };
35
mls_context_init(struct context * c)36 static inline void mls_context_init(struct context *c)
37 {
38 memset(&c->range, 0, sizeof(c->range));
39 }
40
mls_context_cpy(struct context * dst,struct context * src)41 static inline int mls_context_cpy(struct context *dst, struct context *src)
42 {
43 int rc;
44
45 if ( !flask_mls_enabled )
46 return 0;
47
48 dst->range.level[0].sens = src->range.level[0].sens;
49 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
50 if ( rc )
51 goto out;
52
53 dst->range.level[1].sens = src->range.level[1].sens;
54 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[1].cat);
55 if ( rc )
56 ebitmap_destroy(&dst->range.level[0].cat);
57 out:
58 return rc;
59 }
60
61 /*
62 * Sets both levels in the MLS range of 'dst' to the low level of 'src'.
63 */
mls_context_cpy_low(struct context * dst,struct context * src)64 static inline int mls_context_cpy_low(struct context *dst, struct context *src)
65 {
66 int rc;
67
68 if ( !flask_mls_enabled )
69 return 0;
70
71 dst->range.level[0].sens = src->range.level[0].sens;
72 rc = ebitmap_cpy(&dst->range.level[0].cat, &src->range.level[0].cat);
73 if ( rc )
74 goto out;
75
76 dst->range.level[1].sens = src->range.level[0].sens;
77 rc = ebitmap_cpy(&dst->range.level[1].cat, &src->range.level[0].cat);
78 if ( rc )
79 ebitmap_destroy(&dst->range.level[0].cat);
80 out:
81 return rc;
82 }
83
mls_context_cmp(struct context * c1,struct context * c2)84 static inline int mls_context_cmp(struct context *c1, struct context *c2)
85 {
86 if ( !flask_mls_enabled )
87 return 1;
88
89 return ((c1->range.level[0].sens == c2->range.level[0].sens) &&
90 ebitmap_cmp(&c1->range.level[0].cat,&c2->range.level[0].cat) &&
91 (c1->range.level[1].sens == c2->range.level[1].sens) &&
92 ebitmap_cmp(&c1->range.level[1].cat,&c2->range.level[1].cat));
93 }
94
mls_context_destroy(struct context * c)95 static inline void mls_context_destroy(struct context *c)
96 {
97 if ( !flask_mls_enabled )
98 return;
99
100 ebitmap_destroy(&c->range.level[0].cat);
101 ebitmap_destroy(&c->range.level[1].cat);
102 mls_context_init(c);
103 }
104
context_init(struct context * c)105 static inline void context_init(struct context *c)
106 {
107 memset(c, 0, sizeof(*c));
108 }
109
context_cpy(struct context * dst,struct context * src)110 static inline int context_cpy(struct context *dst, struct context *src)
111 {
112 dst->user = src->user;
113 dst->role = src->role;
114 dst->type = src->type;
115 return mls_context_cpy(dst, src);
116 }
117
context_destroy(struct context * c)118 static inline void context_destroy(struct context *c)
119 {
120 c->user = c->role = c->type = 0;
121 mls_context_destroy(c);
122 }
123
context_cmp(struct context * c1,struct context * c2)124 static inline int context_cmp(struct context *c1, struct context *c2)
125 {
126 return ((c1->user == c2->user) &&
127 (c1->role == c2->role) &&
128 (c1->type == c2->type) &&
129 mls_context_cmp(c1, c2));
130 }
131
132 #endif /* _SS_CONTEXT_H_ */
133
134