1 /*
2 * EAP peer: Method registration
3 * Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10 #ifdef CONFIG_DYNAMIC_EAP_METHODS
11 #include <dlfcn.h>
12 #endif /* CONFIG_DYNAMIC_EAP_METHODS */
13
14 #include "common.h"
15 #include "eap_i.h"
16 #include "eap_methods.h"
17
18
19 static struct eap_method *eap_methods = NULL;
20
21 static void eap_peer_method_free(struct eap_method *method);
22
23
24 /**
25 * eap_peer_get_eap_method - Get EAP method based on type number
26 * @vendor: EAP Vendor-Id (0 = IETF)
27 * @method: EAP type number
28 * Returns: Pointer to EAP method or %NULL if not found
29 */
eap_peer_get_eap_method(int vendor,EapType method)30 const struct eap_method * eap_peer_get_eap_method(int vendor, EapType method)
31 {
32 struct eap_method *m;
33 for (m = eap_methods; m; m = m->next) {
34 if (m->vendor == vendor && m->method == method)
35 return m;
36 }
37 return NULL;
38 }
39
40
41 /**
42 * eap_peer_get_type - Get EAP type for the given EAP method name
43 * @name: EAP method name, e.g., TLS
44 * @vendor: Buffer for returning EAP Vendor-Id
45 * Returns: EAP method type or %EAP_TYPE_NONE if not found
46 *
47 * This function maps EAP type names into EAP type numbers based on the list of
48 * EAP methods included in the build.
49 */
eap_peer_get_type(const char * name,int * vendor)50 EapType eap_peer_get_type(const char *name, int *vendor)
51 {
52 struct eap_method *m;
53 for (m = eap_methods; m; m = m->next) {
54 if (os_strcmp(m->name, name) == 0) {
55 *vendor = m->vendor;
56 return m->method;
57 }
58 }
59 *vendor = EAP_VENDOR_IETF;
60 return EAP_TYPE_NONE;
61 }
62
63
64 /**
65 * eap_get_name - Get EAP method name for the given EAP type
66 * @vendor: EAP Vendor-Id (0 = IETF)
67 * @type: EAP method type
68 * Returns: EAP method name, e.g., TLS, or %NULL if not found
69 *
70 * This function maps EAP type numbers into EAP type names based on the list of
71 * EAP methods included in the build.
72 */
eap_get_name(int vendor,EapType type)73 const char * eap_get_name(int vendor, EapType type)
74 {
75 struct eap_method *m;
76 if (vendor == EAP_VENDOR_IETF && type == EAP_TYPE_EXPANDED)
77 return "expanded";
78 for (m = eap_methods; m; m = m->next) {
79 if (m->vendor == vendor && m->method == type)
80 return m->name;
81 }
82 return NULL;
83 }
84
85
86 /**
87 * eap_get_names - Get space separated list of names for supported EAP methods
88 * @buf: Buffer for names
89 * @buflen: Buffer length
90 * Returns: Number of characters written into buf (not including nul
91 * termination)
92 */
eap_get_names(char * buf,size_t buflen)93 size_t eap_get_names(char *buf, size_t buflen)
94 {
95 char *pos, *end;
96 struct eap_method *m;
97 int ret;
98
99 if (buflen == 0)
100 return 0;
101
102 pos = buf;
103 end = pos + buflen;
104
105 for (m = eap_methods; m; m = m->next) {
106 ret = os_snprintf(pos, end - pos, "%s%s",
107 m == eap_methods ? "" : " ", m->name);
108 if (os_snprintf_error(end - pos, ret))
109 break;
110 pos += ret;
111 }
112 buf[buflen - 1] = '\0';
113
114 return pos - buf;
115 }
116
117
118 /**
119 * eap_get_names_as_string_array - Get supported EAP methods as string array
120 * @num: Buffer for returning the number of items in array, not including %NULL
121 * terminator. This parameter can be %NULL if the length is not needed.
122 * Returns: A %NULL-terminated array of strings, or %NULL on error.
123 *
124 * This function returns the list of names for all supported EAP methods as an
125 * array of strings. The caller must free the returned array items and the
126 * array.
127 */
eap_get_names_as_string_array(size_t * num)128 char ** eap_get_names_as_string_array(size_t *num)
129 {
130 struct eap_method *m;
131 size_t array_len = 0;
132 char **array;
133 int i = 0, j;
134
135 for (m = eap_methods; m; m = m->next)
136 array_len++;
137
138 array = os_calloc(array_len + 1, sizeof(char *));
139 if (array == NULL)
140 return NULL;
141
142 for (m = eap_methods; m; m = m->next) {
143 array[i++] = os_strdup(m->name);
144 if (array[i - 1] == NULL) {
145 for (j = 0; j < i; j++)
146 os_free(array[j]);
147 os_free(array);
148 return NULL;
149 }
150 }
151 array[i] = NULL;
152
153 if (num)
154 *num = array_len;
155
156 return array;
157 }
158
159
160 /**
161 * eap_peer_get_methods - Get a list of enabled EAP peer methods
162 * @count: Set to number of available methods
163 * Returns: List of enabled EAP peer methods
164 */
eap_peer_get_methods(size_t * count)165 const struct eap_method * eap_peer_get_methods(size_t *count)
166 {
167 int c = 0;
168 struct eap_method *m;
169
170 for (m = eap_methods; m; m = m->next)
171 c++;
172
173 *count = c;
174 return eap_methods;
175 }
176
177
178 #ifdef CONFIG_DYNAMIC_EAP_METHODS
179 /**
180 * eap_peer_method_load - Load a dynamic EAP method library (shared object)
181 * @so: File path for the shared object file to load
182 * Returns: 0 on success, -1 on failure
183 */
eap_peer_method_load(const char * so)184 int eap_peer_method_load(const char *so)
185 {
186 void *handle;
187 int (*dyn_init)(void);
188 int ret;
189
190 handle = dlopen(so, RTLD_LAZY);
191 if (handle == NULL) {
192 wpa_printf(MSG_ERROR, "EAP: Failed to open dynamic EAP method "
193 "'%s': %s", so, dlerror());
194 return -1;
195 }
196
197 dyn_init = dlsym(handle, "eap_peer_method_dynamic_init");
198 if (dyn_init == NULL) {
199 dlclose(handle);
200 wpa_printf(MSG_ERROR, "EAP: Invalid EAP method '%s' - no "
201 "eap_peer_method_dynamic_init()", so);
202 return -1;
203 }
204
205 ret = dyn_init();
206 if (ret) {
207 dlclose(handle);
208 wpa_printf(MSG_ERROR, "EAP: Failed to add EAP method '%s' - "
209 "ret %d", so, ret);
210 return ret;
211 }
212
213 /* Store the handle for this shared object. It will be freed with
214 * dlclose() when the EAP method is unregistered. */
215 eap_methods->dl_handle = handle;
216
217 wpa_printf(MSG_DEBUG, "EAP: Loaded dynamic EAP method: '%s'", so);
218
219 return 0;
220 }
221
222
223 /**
224 * eap_peer_method_unload - Unload a dynamic EAP method library (shared object)
225 * @method: Pointer to the dynamically loaded EAP method
226 * Returns: 0 on success, -1 on failure
227 *
228 * This function can be used to unload EAP methods that have been previously
229 * loaded with eap_peer_method_load(). Before unloading the method, all
230 * references to the method must be removed to make sure that no dereferences
231 * of freed memory will occur after unloading.
232 */
eap_peer_method_unload(struct eap_method * method)233 int eap_peer_method_unload(struct eap_method *method)
234 {
235 struct eap_method *m, *prev;
236 void *handle;
237
238 m = eap_methods;
239 prev = NULL;
240 while (m) {
241 if (m == method)
242 break;
243 prev = m;
244 m = m->next;
245 }
246
247 if (m == NULL || m->dl_handle == NULL)
248 return -1;
249
250 if (prev)
251 prev->next = m->next;
252 else
253 eap_methods = m->next;
254
255 handle = m->dl_handle;
256
257 if (m->free)
258 m->free(m);
259 else
260 eap_peer_method_free(m);
261
262 dlclose(handle);
263
264 return 0;
265 }
266 #endif /* CONFIG_DYNAMIC_EAP_METHODS */
267
268
269 /**
270 * eap_peer_method_alloc - Allocate EAP peer method structure
271 * @version: Version of the EAP peer method interface (set to
272 * EAP_PEER_METHOD_INTERFACE_VERSION)
273 * @vendor: EAP Vendor-ID (EAP_VENDOR_*) (0 = IETF)
274 * @method: EAP type number (EAP_TYPE_*)
275 * @name: Name of the method (e.g., "TLS")
276 * Returns: Allocated EAP method structure or %NULL on failure
277 *
278 * The returned structure should be freed with eap_peer_method_free() when it
279 * is not needed anymore.
280 */
eap_peer_method_alloc(int version,int vendor,EapType method,const char * name)281 struct eap_method * eap_peer_method_alloc(int version, int vendor,
282 EapType method, const char *name)
283 {
284 struct eap_method *eap;
285 eap = os_zalloc(sizeof(*eap));
286 if (eap == NULL)
287 return NULL;
288 eap->version = version;
289 eap->vendor = vendor;
290 eap->method = method;
291 eap->name = name;
292 return eap;
293 }
294
295
296 /**
297 * eap_peer_method_free - Free EAP peer method structure
298 * @method: Method structure allocated with eap_peer_method_alloc()
299 */
eap_peer_method_free(struct eap_method * method)300 static void eap_peer_method_free(struct eap_method *method)
301 {
302 os_free(method);
303 }
304
305
306 /**
307 * eap_peer_method_register - Register an EAP peer method
308 * @method: EAP method to register from eap_peer_method_alloc()
309 * Returns: 0 on success, -1 on invalid method, or -2 if a matching EAP method
310 * has already been registered
311 *
312 * Each EAP peer method needs to call this function to register itself as a
313 * supported EAP method. The caller must not free the allocated method data
314 * regardless of the return value.
315 */
eap_peer_method_register(struct eap_method * method)316 int eap_peer_method_register(struct eap_method *method)
317 {
318 struct eap_method *m, *last = NULL;
319
320 if (method == NULL || method->name == NULL ||
321 method->version != EAP_PEER_METHOD_INTERFACE_VERSION) {
322 eap_peer_method_free(method);
323 return -1;
324 }
325
326 for (m = eap_methods; m; m = m->next) {
327 if ((m->vendor == method->vendor &&
328 m->method == method->method) ||
329 os_strcmp(m->name, method->name) == 0) {
330 eap_peer_method_free(method);
331 return -2;
332 }
333 last = m;
334 }
335
336 if (last)
337 last->next = method;
338 else
339 eap_methods = method;
340
341 return 0;
342 }
343
344
345 /**
346 * eap_peer_unregister_methods - Unregister EAP peer methods
347 *
348 * This function is called at program termination to unregister all EAP peer
349 * methods.
350 */
eap_peer_unregister_methods(void)351 void eap_peer_unregister_methods(void)
352 {
353 struct eap_method *m;
354 #ifdef CONFIG_DYNAMIC_EAP_METHODS
355 void *handle;
356 #endif /* CONFIG_DYNAMIC_EAP_METHODS */
357
358 while (eap_methods) {
359 m = eap_methods;
360 eap_methods = eap_methods->next;
361
362 #ifdef CONFIG_DYNAMIC_EAP_METHODS
363 handle = m->dl_handle;
364 #endif /* CONFIG_DYNAMIC_EAP_METHODS */
365
366 if (m->free)
367 m->free(m);
368 else
369 eap_peer_method_free(m);
370
371 #ifdef CONFIG_DYNAMIC_EAP_METHODS
372 if (handle)
373 dlclose(handle);
374 #endif /* CONFIG_DYNAMIC_EAP_METHODS */
375 }
376 }
377