rlm_ippool.c

RADIUS认证协议

/*
 * rlm_ippool.c
 *
 * Version:  $Id: rlm_ippool.c,v 1.31 2004/05/03 10:51:26 kkalev Exp $
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Copyright 2001  The FreeRADIUS server project
 * Copyright 2002  Kostas Kalevras <[e-mail]>
 *
 * March 2002, Kostas Kalevras <[e-mail]>
 * - Initial release
 * April 2002, Kostas Kalevras <[e-mail]>
 * - Add support for the Pool-Name attribute
 * May 2002, Kostas Kalevras <[e-mail]>
 * - Check the return value of a gdbm_fetch() we didn't check
 * - Change the nas entry in the ippool_key structure from uint32 to string[64]
 *   That should allow us to also use the NAS-Identifier attribute
 * Sep 2002, Kostas Kalevras <[e-mail]>
 * - Move from authorize to post-auth
 * - Use mutex locks when accessing the gdbm files
 * - Fail if we don't find nas port information
 * Oct 2002, Kostas Kalevras <[e-mail]>
 * - Do a memset(0) on the key.nas before doing searches. Nusty bug
 * Jul 2003, Kostas Kalevras <[e-mail]>
 * - Make Multilink work this time
 * - Instead of locking file operations, lock transactions. That means we only keep
 *   one big transaction lock instead of per file locks (mutexes).
 * Sep 2003, Kostas Kalevras <[e-mail]>
 * - Fix postauth to not leak ip's
 *   Add an extra attribute in each entry <char extra> signifying if we need to delete this
 *   entry in the accounting phase. This is only true in case we are doing MPPP
 *   Various other code changes. Code comments should explain things
 *   Highly experimental at this phase.
 * Mar 2004, Kostas Kalevras <[e-mail]>
 * - Add a timestamp and a timeout attribute in ippool_info. When we assign an ip we set timestamp
 *   to request->timestamp and timeout to %{Session-Timeout:-0}. When we search for a free entry
 *   we check if timeout has expired. If it has then we free the entry. We also add a maximum
 *   timeout configuration directive. If it is non zero then we also use that one to free entries.
 */

#include "config.h"
#include "autoconf.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif

#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif

#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif

#include "radiusd.h"
#include "modules.h"
#include "conffile.h"

#include <gdbm.h>
#include <time.h>

#ifdef NEEDS_GDBM_SYNC
#	define GDBM_SYNCOPT GDBM_SYNC
#else
#	define GDBM_SYNCOPT 0
#endif

#ifdef GDBM_NOLOCK
#define GDBM_IPPOOL_OPTS (GDBM_SYNCOPT | GDBM_NOLOCK)
#else
#define GDBM_IPPOOL_OPTS (GDBM_SYNCOPT)
#endif

#define MAX_NAS_NAME_SIZE 64

static const char rcsid[] = "$Id: rlm_ippool.c,v 1.31 2004/05/03 10:51:26 kkalev Exp $";

/*
 *	Define a structure for our module configuration.
 *
 *	These variables do not need to be in a structure, but it's
 *	a lot cleaner to do so, and a pointer to the structure can
 *	be used as the instance handle.
 */
typedef struct rlm_ippool_t {
	char *session_db;
	char *ip_index;
	char *name;
	uint32_t range_start;
	uint32_t range_stop;
	uint32_t netmask;
	time_t max_timeout;
	int cache_size;
	int override;
	GDBM_FILE gdbm;
	GDBM_FILE ip;
#ifdef HAVE_PTHREAD_H
	pthread_mutex_t op_mutex;
#endif
} rlm_ippool_t;

#ifndef HAVE_PTHREAD_H
/*
 *	This is easier than ifdef's throughout the code.
 */
#define pthread_mutex_init(_x, _y)
#define pthread_mutex_destroy(_x)
#define pthread_mutex_lock(_x)
#define pthread_mutex_unlock(_x)
#endif

typedef struct ippool_info {
	uint32_t	ipaddr;
	char		active;
	char		cli[32];
	char		extra;
	time_t		timestamp;
	time_t		timeout;
} ippool_info;

typedef struct ippool_key {
	char nas[MAX_NAS_NAME_SIZE];
	unsigned int port;
} ippool_key;

/*
 *	A mapping of configuration file names to internal variables.
 *
 *	Note that the string is dynamically allocated, so it MUST
 *	be freed.  When the configuration file parse re-reads the string,
 *	it free's the old one, and strdup's the new one, placing the pointer
 *	to the strdup'd string into 'config.string'.  This gets around
 *	buffer over-flows.
 */
static CONF_PARSER module_config[] = {
  { "session-db", PW_TYPE_STRING_PTR, offsetof(rlm_ippool_t,session_db), NULL, NULL },
  { "ip-index", PW_TYPE_STRING_PTR, offsetof(rlm_ippool_t,ip_index), NULL, NULL },
  { "range-start", PW_TYPE_IPADDR, offsetof(rlm_ippool_t,range_start), NULL, "0" },
  { "range-stop", PW_TYPE_IPADDR, offsetof(rlm_ippool_t,range_stop), NULL, "0" },
  { "netmask", PW_TYPE_IPADDR, offsetof(rlm_ippool_t,netmask), NULL, "0" },
  { "cache-size", PW_TYPE_INTEGER, offsetof(rlm_ippool_t,cache_size), NULL, "1000" },
  { "override", PW_TYPE_BOOLEAN, offsetof(rlm_ippool_t,override), NULL, "no" },
  { "maximum-timeout", PW_TYPE_INTEGER, offsetof(rlm_ippool_t,max_timeout), NULL, "0" },
  { NULL, -1, 0, NULL, NULL }
};


/*
 *	Do any per-module initialization that is separate to each
 *	configured instance of the module.  e.g. set up connections
 *	to external databases, read configuration files, set up
 *	dictionary entries, etc.
 *
 *	If configuration information is given in the config section
 *	that must be referenced in later calls, store a handle to it
 *	in *instance otherwise put a null pointer there.
 */
static int ippool_instantiate(CONF_SECTION *conf, void **instance)
{
	rlm_ippool_t *data;
	int cache_size;
	ippool_info entry;
	ippool_key key;
	datum key_datum;
	datum data_datum;
	int i;
	unsigned j;
	const char *cli = "0";
	char *pool_name = NULL;

	/*
	 *	Set up a storage area for instance data
	 */
	data = rad_malloc(sizeof(*data));
	if (!data) {
		return -1;
	}
	memset(data, 0, sizeof(*data));

	/*
	 *	If the configuration parameters can't be parsed, then
	 *	fail.
	 */
	if (cf_section_parse(conf, data, module_config) < 0) {
		free(data);
		return -1;
	}
	cache_size = data->cache_size;

	if (data->session_db == NULL) {
		radlog(L_ERR, "rlm_ippool: 'session-db' must be set.");
		free(data);
		return -1;
	}
	if (data->ip_index == NULL) {
		radlog(L_ERR, "rlm_ippool: 'ip-index' must be set.");
		free(data);
		return -1;
	}
	data->range_start = htonl(data->range_start);
	data->range_stop = htonl(data->range_stop);
	data->netmask = htonl(data->netmask);
	if (data->range_start == 0 || data->range_stop == 0 || \
			 data->range_start >= data->range_stop ) {
		radlog(L_ERR, "rlm_ippool: Invalid configuration data given.");
		free(data);
		return -1;
	}

	data->gdbm = gdbm_open(data->session_db, sizeof(int),
			GDBM_WRCREAT | GDBM_IPPOOL_OPTS, 0600, NULL);
	if (data->gdbm == NULL) {
		radlog(L_ERR, "rlm_ippool: Failed to open file %s: %s",
				data->session_db, strerror(errno));
		return -1;
	}
	data->ip = gdbm_open(data->ip_index, sizeof(int),
			GDBM_WRCREAT | GDBM_IPPOOL_OPTS, 0600, NULL);
	if (data->ip == NULL) {
		radlog(L_ERR, "rlm_ippool: Failed to open file %s: %s",
				data->ip_index, strerror(errno));
		return -1;
	}
	if (gdbm_setopt(data->gdbm, GDBM_CACHESIZE, &cache_size, sizeof(int)) == -1)
		radlog(L_ERR, "rlm_ippool: Failed to set cache size");
	if (gdbm_setopt(data->ip, GDBM_CACHESIZE, &cache_size, sizeof(int)) == -1)
		radlog(L_ERR, "rlm_ippool: Failed to set cache size");

	key_datum = gdbm_firstkey(data->gdbm);
	if (key_datum.dptr == NULL){
			/*
			 * If the database does not exist initialize it.
			 * We set the nas/port pairs to not existent values and
			 * active = 0
			 */
		int rcode;
		uint32_t or_result;
		char str[32];
		const char *nas_init = "NOT_EXIST";

		DEBUG("rlm_ippool: Initializing database");
		for(i=data->range_start,j=~0;i<=data->range_stop;i++,j--){

			/*
			 * Net and Broadcast addresses are excluded
			 */
			or_result = i | data->netmask;
			if (~data->netmask != 0 &&
				(or_result == data->netmask ||
			    (~or_result == 0))) {
				DEBUG("rlm_ippool: IP %s excluded",
				      ip_ntoa(str, ntohl(i)));
				continue;
			}

			strcpy(key.nas, nas_init);
			key.port = j;
			key_datum.dptr = (char *) &key;
			key_datum.dsize = sizeof(ippool_key);

			entry.ipaddr = ntohl(i);
			entry.active = 0;
			entry.extra = 0;
			entry.timestamp = 0;
			entry.timeout = 0;
			strcpy(entry.cli,cli);

			data_datum.dptr = (char *) &entry;
			data_datum.dsize = sizeof(ippool_info);

			rcode = gdbm_store(data->gdbm, key_datum, data_datum, GDBM_REPLACE);
			if (rcode < 0) {
				radlog(L_ERR, "rlm_ippool: Failed storing data to %s: %s",
						data->session_db, gdbm_strerror(gdbm_errno));
				free(data);
				gdbm_close(data->gdbm);
				gdbm_close(data->ip);
				return -1;
			}
		}
	}
	else
		free(key_datum.dptr);

	/* Add the ip pool name */
	data->name = NULL;
	pool_name = cf_section_name2(conf);
	if (pool_name != NULL)
		data->name = strdup(pool_name);

	pthread_mutex_init(&data->op_mutex, NULL);
	*instance = data;

	return 0;
}


/*
 *	Check for an Accounting-Stop
 *	If we find one and we have allocated an IP to this nas/port combination, deallocate it.
 */
static int ippool_accounting(void *instance, REQUEST *request)
{
	rlm_ippool_t *data = (rlm_ippool_t *)instance;
	datum key_datum;
	datum data_datum;
	datum save_datum;
	int acctstatustype = 0;
	unsigned int port = ~0;
	int rcode;
	char nas[MAX_NAS_NAME_SIZE];
	ippool_info entry;
	ippool_key key;
	int num = 0;
	VALUE_PAIR *vp;
	char str[32];


	if ((vp = pairfind(request->packet->vps, PW_ACCT_STATUS_TYPE)) != NULL)
		acctstatustype = vp->lvalue;
	else {
		DEBUG("rlm_ippool: Could not find account status type in packet. Return NOOP.");
		return RLM_MODULE_NOOP;
	}
	switch(acctstatustype){
		case PW_STATUS_STOP:
			if ((vp = pairfind(request->packet->vps, PW_NAS_PORT)) != NULL)
				port = vp->lvalue;
			else {
				DEBUG("rlm_ippool: Could not find port number in packet. Return NOOP.");
				return RLM_MODULE_NOOP;
			}
			if ((vp = pairfind(request->packet->vps, PW_NAS_IP_ADDRESS)) != NULL)
				strncpy(nas, vp->strvalue, MAX_NAS_NAME_SIZE - 1);
			else {
				if ((vp = pairfind(request->packet->vps, PW_NAS_IDENTIFIER)) != NULL)
					strncpy(nas, vp->strvalue, MAX_NAS_NAME_SIZE - 1);
				else {
					DEBUG("rlm_ippool: Could not find nas information in packet. Return NOOP.");
					return RLM_MODULE_NOOP;
				}
			}
			break;
		default:
			/* We don't care about any other accounting packet */
			DEBUG("rlm_ippool: This is not an Accounting-Stop. Return NOOP.");

			return RLM_MODULE_NOOP;
	}

	memset(key.nas,0,MAX_NAS_NAME_SIZE);
	strncpy(key.nas,nas,MAX_NAS_NAME_SIZE -1 );
	key.port = port;
	DEBUG("rlm_ippool: Searching for an entry for nas/port: %s/%u",key.nas,key.port);
	key_datum.dptr = (char *) &key;
	key_datum.dsize = sizeof(ippool_key);

	pthread_mutex_lock(&data->op_mutex);
	data_datum = gdbm_fetch(data->gdbm, key_datum);
	if (data_datum.dptr != NULL){

		/*
		 * If the entry was found set active to zero
		 */
		memcpy(&entry, data_datum.dptr, sizeof(ippool_info));
		free(data_datum.dptr);
		DEBUG("rlm_ippool: Deallocated entry for ip/port: %s/%u",ip_ntoa(str,entry.ipaddr),port);
		entry.active = 0;
		entry.timestamp = 0;
		entry.timeout = 0;

		/*
		 * Save the reference to the entry
		 */
		save_datum.dptr = key_datum.dptr;
		save_datum.dsize = key_datum.dsize;

		data_datum.dptr = (char *) &entry;
		data_datum.dsize = sizeof(ippool_info);

		rcode = gdbm_store(data->gdbm, key_datum, data_datum, GDBM_REPLACE);
		if (rcode < 0) {
			radlog(L_ERR, "rlm_ippool: Failed storing data to %s: %s",
					data->session_db, gdbm_strerror(gdbm_errno));
			pthread_mutex_unlock(&data->op_mutex);
			return RLM_MODULE_FAIL;
		}

		/*
		 * Decrease allocated count from the ip index
		 */
		key_datum.dptr = (char *) &entry.ipaddr;
		key_datum.dsize = sizeof(uint32_t);
		data_datum = gdbm_fetch(data->ip, key_datum);
		if (data_datum.dptr != NULL){
			memcpy(&num, data_datum.dptr, sizeof(int));
			free(data_datum.dptr);
			if (num >0){
				num--;
				DEBUG("rlm_ippool: num: %d",num);
				data_datum.dptr = (char *) &num;
				data_datum.dsize = sizeof(int);
				rcode = gdbm_store(data->ip, key_datum, data_datum, GDBM_REPLACE);
				if (rcode < 0) {
					radlog(L_ERR, "rlm_ippool: Failed storing data to %s: %s",
							data->ip_index, gdbm_strerror(gdbm_errno));
					pthread_mutex_unlock(&data->op_mutex);
					return RLM_MODULE_FAIL;
				}
				if (num >0 && entry.extra == 1){
					/*
					 * We are doing MPPP and we still have nas/port entries referencing
					 * this ip. Delete this entry so that eventually we only keep one
					 * reference to this ip.
					 */
					gdbm_delete(data->gdbm,save_datum);
				}
			}
		}
		pthread_mutex_unlock(&data->op_mutex);
	}
	else{
		pthread_mutex_unlock(&data->op_mutex);