text: /*
   * External password backend
   * Copyright (c) 2012, Jouni Malinen <j@w1.fi>
   *
   * This software may be distributed under the terms of the BSD license.
   * See README for more details.
   */
  
  #include "includes.h"
  
  #ifdef __linux__
  #include <sys/mman.h>
  #endif /* __linux__ */
  
  #include "common.h"
  #include "ext_password_i.h"
  
  
  #ifdef CONFIG_EXT_PASSWORD_TEST
  extern struct ext_password_backend ext_password_test;
  #endif /* CONFIG_EXT_PASSWORD_TEST */
  
  static const struct ext_password_backend *backends[] = {
  #ifdef CONFIG_EXT_PASSWORD_TEST
  	&ext_password_test,
  #endif /* CONFIG_EXT_PASSWORD_TEST */
  	NULL
  };
  
  struct ext_password_data {
  	const struct ext_password_backend *backend;
  	void *priv;
  };
  
  
  struct ext_password_data * ext_password_init(const char *backend,
  					     const char *params)
  {
  	struct ext_password_data *data;
  	int i;
  
  	data = os_zalloc(sizeof(*data));
  	if (data == NULL)
  		return NULL;
  
  	for (i = 0; backends[i]; i++) {
  		if (os_strcmp(backends[i]->name, backend) == 0) {
  			data->backend = backends[i];
  			break;
  		}
  	}
  
  	if (!data->backend) {
  		os_free(data);
  		return NULL;
  	}
  
  	data->priv = data->backend->init(params);
  	if (data->priv == NULL) {
  		os_free(data);
  		return NULL;
  	}
  
  	return data;
  }
  
  
  void ext_password_deinit(struct ext_password_data *data)
  {
  	if (data && data->backend && data->priv)
  		data->backend->deinit(data->priv);
  	os_free(data);
  }
  
  
  struct wpabuf * ext_password_get(struct ext_password_data *data,
  				 const char *name)
  {
  	if (data == NULL)
  		return NULL;
  	return data->backend->get(data->priv, name);
  }
  
  
  struct wpabuf * ext_password_alloc(size_t len)
  {
  	struct wpabuf *buf;
  
  	buf = wpabuf_alloc(len);
  	if (buf == NULL)
  		return NULL;
  
  #ifdef __linux__
  	if (mlock(wpabuf_head(buf), wpabuf_len(buf)) < 0) {
  		wpa_printf(MSG_ERROR, "EXT PW: mlock failed: %s",
  			   strerror(errno));
  	}
  #endif /* __linux__ */
  
  	return buf;
  }
  
  
  void ext_password_free(struct wpabuf *pw)
  {
  	if (pw == NULL)
  		return;
  	os_memset(wpabuf_mhead(pw), 0, wpabuf_len(pw));
  #ifdef __linux__
  	if (munlock(wpabuf_head(pw), wpabuf_len(pw)) < 0) {
  		wpa_printf(MSG_ERROR, "EXT PW: munlock failed: %s",
  			   strerror(errno));
  	}
  #endif /* __linux__ */
  	wpabuf_free(pw);
  }
  