hostapd/src/eap_peer/eap_methods.c
Jouni Malinen 127608152e Move EAP method registration away from src/eap_{peer,server}
This makes it easier to make a library out of EAP methods without
losing possiblity of binary size optimization by linker dropping
unreferenced code.
2009-12-06 11:28:41 +02:00

373 lines
8.5 KiB
C

/*
* EAP peer: Method registration
* Copyright (c) 2004-2007, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "includes.h"
#ifdef CONFIG_DYNAMIC_EAP_METHODS
#include <dlfcn.h>
#endif /* CONFIG_DYNAMIC_EAP_METHODS */
#include "common.h"
#include "eap_i.h"
#include "eap_methods.h"
static struct eap_method *eap_methods = NULL;
/**
* eap_peer_get_eap_method - Get EAP method based on type number
* @vendor: EAP Vendor-Id (0 = IETF)
* @method: EAP type number
* Returns: Pointer to EAP method or %NULL if not found
*/
const struct eap_method * eap_peer_get_eap_method(int vendor, EapType method)
{
struct eap_method *m;
for (m = eap_methods; m; m = m->next) {
if (m->vendor == vendor && m->method == method)
return m;
}
return NULL;
}
/**
* eap_peer_get_type - Get EAP type for the given EAP method name
* @name: EAP method name, e.g., TLS
* @vendor: Buffer for returning EAP Vendor-Id
* Returns: EAP method type or %EAP_TYPE_NONE if not found
*
* This function maps EAP type names into EAP type numbers based on the list of
* EAP methods included in the build.
*/
EapType eap_peer_get_type(const char *name, int *vendor)
{
struct eap_method *m;
for (m = eap_methods; m; m = m->next) {
if (os_strcmp(m->name, name) == 0) {
*vendor = m->vendor;
return m->method;
}
}
*vendor = EAP_VENDOR_IETF;
return EAP_TYPE_NONE;
}
/**
* eap_get_name - Get EAP method name for the given EAP type
* @vendor: EAP Vendor-Id (0 = IETF)
* @type: EAP method type
* Returns: EAP method name, e.g., TLS, or %NULL if not found
*
* This function maps EAP type numbers into EAP type names based on the list of
* EAP methods included in the build.
*/
const char * eap_get_name(int vendor, EapType type)
{
struct eap_method *m;
for (m = eap_methods; m; m = m->next) {
if (m->vendor == vendor && m->method == type)
return m->name;
}
return NULL;
}
/**
* eap_get_names - Get space separated list of names for supported EAP methods
* @buf: Buffer for names
* @buflen: Buffer length
* Returns: Number of characters written into buf (not including nul
* termination)
*/
size_t eap_get_names(char *buf, size_t buflen)
{
char *pos, *end;
struct eap_method *m;
int ret;
if (buflen == 0)
return 0;
pos = buf;
end = pos + buflen;
for (m = eap_methods; m; m = m->next) {
ret = os_snprintf(pos, end - pos, "%s%s",
m == eap_methods ? "" : " ", m->name);
if (ret < 0 || ret >= end - pos)
break;
pos += ret;
}
buf[buflen - 1] = '\0';
return pos - buf;
}
/**
* eap_get_names_as_string_array - Get supported EAP methods as string array
* @num: Buffer for returning the number of items in array, not including %NULL
* terminator. This parameter can be %NULL if the length is not needed.
* Returns: A %NULL-terminated array of strings, or %NULL on error.
*
* This function returns the list of names for all supported EAP methods as an
* array of strings. The caller must free the returned array items and the
* array.
*/
char ** eap_get_names_as_string_array(size_t *num)
{
struct eap_method *m;
size_t array_len = 0;
char **array;
int i = 0, j;
for (m = eap_methods; m; m = m->next)
array_len++;
array = os_zalloc(sizeof(char *) * (array_len + 1));
if (array == NULL)
return NULL;
for (m = eap_methods; m; m = m->next) {
array[i++] = os_strdup(m->name);
if (array[i - 1] == NULL) {
for (j = 0; j < i; j++)
os_free(array[j]);
os_free(array);
return NULL;
}
}
array[i] = NULL;
if (num)
*num = array_len;
return array;
}
/**
* eap_peer_get_methods - Get a list of enabled EAP peer methods
* @count: Set to number of available methods
* Returns: List of enabled EAP peer methods
*/
const struct eap_method * eap_peer_get_methods(size_t *count)
{
int c = 0;
struct eap_method *m;
for (m = eap_methods; m; m = m->next)
c++;
*count = c;
return eap_methods;
}
#ifdef CONFIG_DYNAMIC_EAP_METHODS
/**
* eap_peer_method_load - Load a dynamic EAP method library (shared object)
* @so: File path for the shared object file to load
* Returns: 0 on success, -1 on failure
*/
int eap_peer_method_load(const char *so)
{
void *handle;
int (*dyn_init)(void);
int ret;
handle = dlopen(so, RTLD_LAZY);
if (handle == NULL) {
wpa_printf(MSG_ERROR, "EAP: Failed to open dynamic EAP method "
"'%s': %s", so, dlerror());
return -1;
}
dyn_init = dlsym(handle, "eap_peer_method_dynamic_init");
if (dyn_init == NULL) {
dlclose(handle);
wpa_printf(MSG_ERROR, "EAP: Invalid EAP method '%s' - no "
"eap_peer_method_dynamic_init()", so);
return -1;
}
ret = dyn_init();
if (ret) {
dlclose(handle);
wpa_printf(MSG_ERROR, "EAP: Failed to add EAP method '%s' - "
"ret %d", so, ret);
return ret;
}
/* Store the handle for this shared object. It will be freed with
* dlclose() when the EAP method is unregistered. */
eap_methods->dl_handle = handle;
wpa_printf(MSG_DEBUG, "EAP: Loaded dynamic EAP method: '%s'", so);
return 0;
}
/**
* eap_peer_method_unload - Unload a dynamic EAP method library (shared object)
* @method: Pointer to the dynamically loaded EAP method
* Returns: 0 on success, -1 on failure
*
* This function can be used to unload EAP methods that have been previously
* loaded with eap_peer_method_load(). Before unloading the method, all
* references to the method must be removed to make sure that no dereferences
* of freed memory will occur after unloading.
*/
int eap_peer_method_unload(struct eap_method *method)
{
struct eap_method *m, *prev;
void *handle;
m = eap_methods;
prev = NULL;
while (m) {
if (m == method)
break;
prev = m;
m = m->next;
}
if (m == NULL || m->dl_handle == NULL)
return -1;
if (prev)
prev->next = m->next;
else
eap_methods = m->next;
handle = m->dl_handle;
if (m->free)
m->free(m);
else
eap_peer_method_free(m);
dlclose(handle);
return 0;
}
#endif /* CONFIG_DYNAMIC_EAP_METHODS */
/**
* eap_peer_method_alloc - Allocate EAP peer method structure
* @version: Version of the EAP peer method interface (set to
* EAP_PEER_METHOD_INTERFACE_VERSION)
* @vendor: EAP Vendor-ID (EAP_VENDOR_*) (0 = IETF)
* @method: EAP type number (EAP_TYPE_*)
* @name: Name of the method (e.g., "TLS")
* Returns: Allocated EAP method structure or %NULL on failure
*
* The returned structure should be freed with eap_peer_method_free() when it
* is not needed anymore.
*/
struct eap_method * eap_peer_method_alloc(int version, int vendor,
EapType method, const char *name)
{
struct eap_method *eap;
eap = os_zalloc(sizeof(*eap));
if (eap == NULL)
return NULL;
eap->version = version;
eap->vendor = vendor;
eap->method = method;
eap->name = name;
return eap;
}
/**
* eap_peer_method_free - Free EAP peer method structure
* @method: Method structure allocated with eap_peer_method_alloc()
*/
void eap_peer_method_free(struct eap_method *method)
{
os_free(method);
}
/**
* eap_peer_method_register - Register an EAP peer method
* @method: EAP method to register
* Returns: 0 on success, -1 on invalid method, or -2 if a matching EAP method
* has already been registered
*
* Each EAP peer method needs to call this function to register itself as a
* supported EAP method.
*/
int eap_peer_method_register(struct eap_method *method)
{
struct eap_method *m, *last = NULL;
if (method == NULL || method->name == NULL ||
method->version != EAP_PEER_METHOD_INTERFACE_VERSION)
return -1;
for (m = eap_methods; m; m = m->next) {
if ((m->vendor == method->vendor &&
m->method == method->method) ||
os_strcmp(m->name, method->name) == 0)
return -2;
last = m;
}
if (last)
last->next = method;
else
eap_methods = method;
return 0;
}
/**
* eap_peer_unregister_methods - Unregister EAP peer methods
*
* This function is called at program termination to unregister all EAP peer
* methods.
*/
void eap_peer_unregister_methods(void)
{
struct eap_method *m;
#ifdef CONFIG_DYNAMIC_EAP_METHODS
void *handle;
#endif /* CONFIG_DYNAMIC_EAP_METHODS */
while (eap_methods) {
m = eap_methods;
eap_methods = eap_methods->next;
#ifdef CONFIG_DYNAMIC_EAP_METHODS
handle = m->dl_handle;
#endif /* CONFIG_DYNAMIC_EAP_METHODS */
if (m->free)
m->free(m);
else
eap_peer_method_free(m);
#ifdef CONFIG_DYNAMIC_EAP_METHODS
if (handle)
dlclose(handle);
#endif /* CONFIG_DYNAMIC_EAP_METHODS */
}
}