1 /*
2  * EAP server method registration
3  * Copyright (c) 2004-2009, 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 
11 #include "common.h"
12 #include "eap_i.h"
13 #include "eap_methods.h"
14 
15 
16 static struct eap_method *eap_methods;
17 
18 
19 /**
20  * eap_server_get_eap_method - Get EAP method based on type number
21  * @vendor: EAP Vendor-Id (0 = IETF)
22  * @method: EAP type number
23  * Returns: Pointer to EAP method or %NULL if not found
24  */
25 const struct eap_method * eap_server_get_eap_method(int vendor, EapType method)
26 {
27 	struct eap_method *m;
28 	for (m = eap_methods; m; m = m->next) {
29 		if (m->vendor == vendor && m->method == method)
30 			return m;
31 	}
32 	return NULL;
33 }
34 
35 
36 /**
37  * eap_server_get_type - Get EAP type for the given EAP method name
38  * @name: EAP method name, e.g., TLS
39  * @vendor: Buffer for returning EAP Vendor-Id
40  * Returns: EAP method type or %EAP_TYPE_NONE if not found
41  *
42  * This function maps EAP type names into EAP type numbers based on the list of
43  * EAP methods included in the build.
44  */
45 EapType eap_server_get_type(const char *name, int *vendor)
46 {
47 	struct eap_method *m;
48 	for (m = eap_methods; m; m = m->next) {
49 		if (os_strcmp(m->name, name) == 0) {
50 			*vendor = m->vendor;
51 			return m->method;
52 		}
53 	}
54 	*vendor = EAP_VENDOR_IETF;
55 	return EAP_TYPE_NONE;
56 }
57 
58 
59 /**
60  * eap_server_method_alloc - Allocate EAP server method structure
61  * @version: Version of the EAP server method interface (set to
62  * EAP_SERVER_METHOD_INTERFACE_VERSION)
63  * @vendor: EAP Vendor-ID (EAP_VENDOR_*) (0 = IETF)
64  * @method: EAP type number (EAP_TYPE_*)
65  * @name: Name of the method (e.g., "TLS")
66  * Returns: Allocated EAP method structure or %NULL on failure
67  *
68  * The returned structure should be freed with eap_server_method_free() when it
69  * is not needed anymore.
70  */
71 struct eap_method * eap_server_method_alloc(int version, int vendor,
72 					    EapType method, const char *name)
73 {
74 	struct eap_method *eap;
75 	eap = os_zalloc(sizeof(*eap));
76 	if (eap == NULL)
77 		return NULL;
78 	eap->version = version;
79 	eap->vendor = vendor;
80 	eap->method = method;
81 	eap->name = name;
82 	return eap;
83 }
84 
85 
86 /**
87  * eap_server_method_free - Free EAP server method structure
88  * @method: Method structure allocated with eap_server_method_alloc()
89  */
90 static void eap_server_method_free(struct eap_method *method)
91 {
92 	os_free(method);
93 }
94 
95 
96 /**
97  * eap_server_method_register - Register an EAP server method
98  * @method: EAP method to register from eap_server_method_alloc()
99  * Returns: 0 on success, -1 on invalid method, or -2 if a matching EAP method
100  * has already been registered
101  *
102  * Each EAP server method needs to call this function to register itself as a
103  * supported EAP method. The caller must not free the allocated method data
104  * regardless of the return value.
105  */
106 int eap_server_method_register(struct eap_method *method)
107 {
108 	struct eap_method *m, *last = NULL;
109 
110 	if (method == NULL || method->name == NULL ||
111 	    method->version != EAP_SERVER_METHOD_INTERFACE_VERSION) {
112 		eap_server_method_free(method);
113 		return -1;
114 	}
115 
116 	for (m = eap_methods; m; m = m->next) {
117 		if ((m->vendor == method->vendor &&
118 		     m->method == method->method) ||
119 		    os_strcmp(m->name, method->name) == 0) {
120 			eap_server_method_free(method);
121 			return -2;
122 		}
123 		last = m;
124 	}
125 
126 	if (last)
127 		last->next = method;
128 	else
129 		eap_methods = method;
130 
131 	return 0;
132 }
133 
134 
135 /**
136  * eap_server_unregister_methods - Unregister EAP server methods
137  *
138  * This function is called at program termination to unregister all EAP server
139  * methods.
140  */
141 void eap_server_unregister_methods(void)
142 {
143 	struct eap_method *m;
144 
145 	while (eap_methods) {
146 		m = eap_methods;
147 		eap_methods = eap_methods->next;
148 
149 		if (m->free)
150 			m->free(m);
151 		else
152 			eap_server_method_free(m);
153 	}
154 }
155 
156 
157 /**
158  * eap_server_get_name - Get EAP method name for the given EAP type
159  * @vendor: EAP Vendor-Id (0 = IETF)
160  * @type: EAP method type
161  * Returns: EAP method name, e.g., TLS, or "unknown" if not found
162  *
163  * This function maps EAP type numbers into EAP type names based on the list of
164  * EAP methods included in the build.
165  */
166 const char * eap_server_get_name(int vendor, EapType type)
167 {
168 	struct eap_method *m;
169 	if (vendor == EAP_VENDOR_IETF && type == EAP_TYPE_EXPANDED)
170 		return "expanded";
171 	for (m = eap_methods; m; m = m->next) {
172 		if (m->vendor == vendor && m->method == type)
173 			return m->name;
174 	}
175 	return "unknown";
176 }
177