1 | #include <assert.h> |
---|
2 | #include <stdlib.h> |
---|
3 | #include <stdio.h> |
---|
4 | #include <string.h> |
---|
5 | |
---|
6 | #include "abac.h" |
---|
7 | #include "abac_util.h" |
---|
8 | |
---|
9 | // typedef'd in role.h |
---|
10 | struct _abac_role_t { |
---|
11 | char *principal; |
---|
12 | char *linked_role; |
---|
13 | char *abac_role_name; |
---|
14 | |
---|
15 | char *string; |
---|
16 | char *linked; |
---|
17 | |
---|
18 | int refcount; |
---|
19 | }; |
---|
20 | |
---|
21 | /** |
---|
22 | * Create a new principal and initialize it. |
---|
23 | */ |
---|
24 | abac_role_t *abac_role_principal_new(char *principal) { |
---|
25 | assert(principal != NULL); |
---|
26 | |
---|
27 | abac_role_t *role; |
---|
28 | |
---|
29 | if (strlen(principal) == 0) |
---|
30 | return NULL; |
---|
31 | |
---|
32 | role = abac_xmalloc(sizeof(abac_role_t)); |
---|
33 | |
---|
34 | role->principal = abac_xstrdup(principal); |
---|
35 | role->abac_role_name = NULL; |
---|
36 | role->linked_role = NULL; |
---|
37 | |
---|
38 | role->string = abac_xstrdup(principal); |
---|
39 | role->linked = NULL; |
---|
40 | |
---|
41 | role->refcount = 1; |
---|
42 | |
---|
43 | return role; |
---|
44 | } |
---|
45 | |
---|
46 | /** |
---|
47 | * Create a new role and initialize it. |
---|
48 | */ |
---|
49 | abac_role_t *abac_role_role_new(char *principal, char *abac_role_name) { |
---|
50 | assert(principal != NULL); |
---|
51 | assert(abac_role_name != NULL); |
---|
52 | |
---|
53 | abac_role_t *role; |
---|
54 | |
---|
55 | if (strlen(principal) == 0 || strlen(abac_role_name) == 0) |
---|
56 | return NULL; |
---|
57 | |
---|
58 | role = abac_xmalloc(sizeof(abac_role_t)); |
---|
59 | |
---|
60 | role->principal = abac_xstrdup(principal); |
---|
61 | role->abac_role_name = abac_xstrdup(abac_role_name); |
---|
62 | role->linked_role = NULL; |
---|
63 | |
---|
64 | int prin_len = strlen(principal); |
---|
65 | int abac_role_len = strlen(abac_role_name); |
---|
66 | |
---|
67 | role->string = abac_xmalloc(prin_len + 1 + abac_role_len + 1); |
---|
68 | memcpy(role->string, principal, prin_len); |
---|
69 | role->string[prin_len] = '.'; |
---|
70 | memcpy(role->string + prin_len + 1, abac_role_name, abac_role_len); |
---|
71 | role->string[prin_len + 1 + abac_role_len] = 0; |
---|
72 | |
---|
73 | role->linked = NULL; |
---|
74 | |
---|
75 | role->refcount = 1; |
---|
76 | |
---|
77 | return role; |
---|
78 | } |
---|
79 | |
---|
80 | /** |
---|
81 | * Created a new linking role and initialize it. |
---|
82 | */ |
---|
83 | abac_role_t *abac_role_linking_new(char *principal, char *linked, char *abac_role_name) { |
---|
84 | assert(principal != NULL); |
---|
85 | assert(linked != NULL); |
---|
86 | assert(abac_role_name != NULL); |
---|
87 | |
---|
88 | abac_role_t *role; |
---|
89 | |
---|
90 | if (strlen(principal) == 0 || strlen(linked) == 0 || strlen(abac_role_name) == 0) |
---|
91 | return NULL; |
---|
92 | |
---|
93 | role = abac_xmalloc(sizeof(abac_role_t)); |
---|
94 | |
---|
95 | role->principal = abac_xstrdup(principal); |
---|
96 | role->linked_role = abac_xstrdup(linked); |
---|
97 | role->abac_role_name = abac_xstrdup(abac_role_name); |
---|
98 | |
---|
99 | int prin_len = strlen(principal); |
---|
100 | int link_len = strlen(linked); |
---|
101 | int abac_role_len = strlen(abac_role_name); |
---|
102 | |
---|
103 | role->string = abac_xmalloc(prin_len + 1 + link_len + 1 + abac_role_len + 1); |
---|
104 | |
---|
105 | memcpy(role->string, principal, prin_len); |
---|
106 | role->string[prin_len] = '.'; |
---|
107 | memcpy(role->string + prin_len + 1, linked, link_len); |
---|
108 | role->string[prin_len + 1 + link_len] = 0; |
---|
109 | |
---|
110 | // hack: linked role is first two parts of full string |
---|
111 | role->linked = abac_xstrdup(role->string); |
---|
112 | |
---|
113 | role->string[prin_len + 1 + link_len] = '.'; |
---|
114 | memcpy(role->string + prin_len + 1 + link_len + 1, abac_role_name, abac_role_len); |
---|
115 | role->string[prin_len + 1 + link_len + 1 + abac_role_len] = 0; |
---|
116 | |
---|
117 | role->refcount = 1; |
---|
118 | |
---|
119 | return role; |
---|
120 | } |
---|
121 | |
---|
122 | /** |
---|
123 | * Decrease a role's reference count, freeing it when it reaches 0. |
---|
124 | */ |
---|
125 | void abac_role_free(abac_role_t *role) { |
---|
126 | if (role == NULL) |
---|
127 | return; |
---|
128 | |
---|
129 | --role->refcount; |
---|
130 | if (role->refcount > 0) |
---|
131 | return; |
---|
132 | |
---|
133 | free(role->principal); |
---|
134 | free(role->linked_role); |
---|
135 | free(role->abac_role_name); |
---|
136 | |
---|
137 | free(role->string); |
---|
138 | free(role->linked); |
---|
139 | |
---|
140 | free(role); |
---|
141 | } |
---|
142 | |
---|
143 | /** |
---|
144 | * Create a role from a string. Handles principals, roles, and linking roles. |
---|
145 | */ |
---|
146 | abac_role_t *abac_role_from_string(char *string) { |
---|
147 | int num_dots = 0; |
---|
148 | char *dot = string; |
---|
149 | |
---|
150 | // count the dots |
---|
151 | while ((dot = strchr(dot, '.')) != NULL) { |
---|
152 | ++num_dots; |
---|
153 | ++dot; |
---|
154 | } |
---|
155 | |
---|
156 | // no dots: easy case, principal |
---|
157 | if (num_dots == 0) |
---|
158 | return abac_role_principal_new(string); |
---|
159 | |
---|
160 | abac_role_t *ret = NULL; |
---|
161 | |
---|
162 | // make a copy so we can mess with it |
---|
163 | string = abac_xstrdup(string); |
---|
164 | |
---|
165 | // a role has exactly 1 dot |
---|
166 | if (num_dots == 1) { |
---|
167 | char *principal = string; |
---|
168 | |
---|
169 | // terminate the principal part |
---|
170 | dot = strchr(principal, '.'); |
---|
171 | *dot = 0; |
---|
172 | |
---|
173 | // role name comes after the dot |
---|
174 | char *abac_role_name = dot + 1; |
---|
175 | |
---|
176 | // create the role (if possible) |
---|
177 | ret = abac_role_role_new(string, abac_role_name); |
---|
178 | } |
---|
179 | |
---|
180 | // a linked role has 2 dots |
---|
181 | else if (num_dots == 2) { |
---|
182 | char *principal = string; |
---|
183 | |
---|
184 | // terminate the principal part |
---|
185 | dot = strchr(principal, '.'); |
---|
186 | *dot = 0; |
---|
187 | |
---|
188 | // linked name is next, terminate it |
---|
189 | char *linked = dot + 1; |
---|
190 | dot = strchr(linked, '.'); |
---|
191 | *dot = 0; |
---|
192 | |
---|
193 | // role name is last, already terminated |
---|
194 | char *abac_role_name = dot + 1; |
---|
195 | |
---|
196 | ret = abac_role_linking_new(principal, linked, abac_role_name); |
---|
197 | } |
---|
198 | |
---|
199 | // more than two dots: return NULL |
---|
200 | |
---|
201 | free(string); |
---|
202 | |
---|
203 | return ret; |
---|
204 | } |
---|
205 | |
---|
206 | /** |
---|
207 | * Increase a role's reference count. |
---|
208 | */ |
---|
209 | abac_role_t *abac_role_dup(abac_role_t *role) { |
---|
210 | assert(role != NULL); |
---|
211 | |
---|
212 | ++role->refcount; |
---|
213 | return role; |
---|
214 | } |
---|
215 | |
---|
216 | /** |
---|
217 | * True if a role is a principal. |
---|
218 | */ |
---|
219 | int abac_role_is_principal(abac_role_t *role) { |
---|
220 | assert(role != NULL); |
---|
221 | return role->abac_role_name == NULL && role->linked_role == NULL; |
---|
222 | } |
---|
223 | |
---|
224 | /** |
---|
225 | * True if a role is a role. |
---|
226 | */ |
---|
227 | int abac_role_is_role(abac_role_t *role) { |
---|
228 | assert(role != NULL); |
---|
229 | return role->abac_role_name != NULL && role->linked_role == NULL; |
---|
230 | } |
---|
231 | |
---|
232 | /** |
---|
233 | * True if a role is a linked role. |
---|
234 | */ |
---|
235 | int abac_role_is_linking(abac_role_t *role) { |
---|
236 | assert(role != NULL); |
---|
237 | return role->linked_role != NULL; |
---|
238 | } |
---|
239 | |
---|
240 | /** |
---|
241 | * Returns the string representation of the role. |
---|
242 | */ |
---|
243 | char *abac_role_string(abac_role_t *role) { |
---|
244 | assert(role != NULL); |
---|
245 | return role->string; |
---|
246 | } |
---|
247 | |
---|
248 | /** |
---|
249 | * Returns the name of a role. If the role is A.r1 then return r1. If the role |
---|
250 | * is A.r1.r2 then return r2. |
---|
251 | */ |
---|
252 | char *abac_role_role_name(abac_role_t *role) { |
---|
253 | assert(role != NULL); |
---|
254 | return role->abac_role_name; |
---|
255 | } |
---|
256 | |
---|
257 | /** |
---|
258 | * Returns the linked part of a linking role. For instance, if the role is |
---|
259 | * A.r1.r2, this returns A.r1. |
---|
260 | */ |
---|
261 | char *abac_role_linked_role(abac_role_t *role) { |
---|
262 | assert(role != NULL); |
---|
263 | return role->linked; |
---|
264 | } |
---|
265 | |
---|
266 | /** |
---|
267 | * Returns the principal part of a role. The stuff before the first dot. |
---|
268 | */ |
---|
269 | char *abac_role_principal(abac_role_t *role) { |
---|
270 | assert(role != NULL); |
---|
271 | return role->principal; |
---|
272 | } |
---|
273 | |
---|
274 | /** |
---|
275 | * Build an attribute key from head and tail roles. Static. |
---|
276 | */ |
---|
277 | #define ROLE_SEPARATOR " <- " |
---|
278 | char *abac_role_attr_key(abac_role_t *head_role, abac_role_t *tail_role) { |
---|
279 | char *head = abac_role_string(head_role); |
---|
280 | int head_len = strlen(head); |
---|
281 | |
---|
282 | char *tail = abac_role_string(tail_role); |
---|
283 | int tail_len = strlen(tail); |
---|
284 | |
---|
285 | int sep_len = sizeof(ROLE_SEPARATOR) - 1; |
---|
286 | |
---|
287 | // "head <- tail" |
---|
288 | char *ret = abac_xmalloc(head_len + tail_len + sep_len + 1); |
---|
289 | memcpy(ret, head, head_len); |
---|
290 | memcpy(ret + head_len, ROLE_SEPARATOR, sep_len); |
---|
291 | memcpy(ret + head_len + sep_len, tail, tail_len); |
---|
292 | ret[head_len + sep_len + tail_len] = 0; |
---|
293 | |
---|
294 | return ret; |
---|
295 | } |
---|