rlm_ippool.c

使用最广泛的radius的linux的源码

		}
		pthread_mutex_unlock(&data->op_mutex);
	}
	else{
		pthread_mutex_unlock(&data->op_mutex);
		DEBUG("rlm_ippool: Entry not found");
	}

	return RLM_MODULE_OK;
}

static int ippool_postauth(void *instance, REQUEST *request)
{
	rlm_ippool_t *data = (rlm_ippool_t *) instance;
	int delete = 0;
	int found = 0;
	int mppp = 0;
	int extra = 0;
	int rcode;
	int num = 0;
	datum key_datum;
	datum nextkey;
	datum data_datum;
	datum save_datum;
	ippool_key key;
	ippool_info entry;
	VALUE_PAIR *vp;
	char *cli = NULL;
	char str[32];
	uint8_t key_str[17];
	char hex_str[35];
	char xlat_str[MAX_STRING_LEN];
	FR_MD5_CTX md5_context;


	/* quiet the compiler */
	instance = instance;
	request = request;

	/* Check if Pool-Name attribute exists. If it exists check our name and
	 * run only if they match
	 */
	if ((vp = pairfind(request->config_items, PW_POOL_NAME)) != NULL){
		if (data->name == NULL || (strcmp(data->name,vp->vp_strvalue) && strcmp(vp->vp_strvalue,"DEFAULT")))
			return RLM_MODULE_NOOP;
	} else {
		DEBUG("rlm_ippool: Could not find Pool-Name attribute.");
		return RLM_MODULE_NOOP;
	}


	/*
	 * Find the caller id
	 */
	if ((vp = pairfind(request->packet->vps, PW_CALLING_STATION_ID)) != NULL)
		cli = vp->vp_strvalue;


	if (!radius_xlat(xlat_str,MAX_STRING_LEN,data->key, request, NULL)){
		DEBUG("rlm_ippool: xlat on the 'key' directive failed");
		return RLM_MODULE_NOOP;
	}
	fr_MD5Init(&md5_context);
	fr_MD5Update(&md5_context, xlat_str, strlen(xlat_str));
	fr_MD5Final(key_str, &md5_context);
	key_str[16] = '\0';
	fr_bin2hex(key_str,hex_str,16);
	hex_str[32] = '\0';
	DEBUG("rlm_ippool: MD5 on 'key' directive maps to: %s",hex_str);
	memcpy(key.key,key_str,16);

	DEBUG("rlm_ippool: Searching for an entry for key: '%s'",hex_str);
	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 there is a corresponding entry in the database with active=1 it is stale.
		 * Set active to zero
		 */
		found = 1;
		memcpy(&entry, data_datum.dptr, sizeof(ippool_info));
		free(data_datum.dptr);
		if (entry.active){
			DEBUG("rlm_ippool: Found a stale entry for ip: %s",ip_ntoa(str,entry.ipaddr));
			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);

	/*
	 * If there is a Framed-IP-Address attribute in the reply, check for override
	 */
	if (pairfind(request->reply->vps, PW_FRAMED_IP_ADDRESS) != NULL) {
		DEBUG("rlm_ippool: Found Framed-IP-Address attribute in reply attribute list.");
		if (data->override)
		{
			/* Override supplied Framed-IP-Address */
			DEBUG("rlm_ippool: override is set to yes. Override the existing Framed-IP-Address attribute.");
			pairdelete(&request->reply->vps, PW_FRAMED_IP_ADDRESS);
		} else {
			/* Abort */
			DEBUG("rlm_ippool: override is set to no. Return NOOP.");
			return RLM_MODULE_NOOP;
		}
	}

	/*
	 * Walk through the database searching for an active=0 entry.
	 * We search twice. Once to see if we have an active entry with the same callerid
	 * so that MPPP can work ok and then once again to find a free entry.
	 */

	pthread_mutex_lock(&data->op_mutex);

	key_datum.dptr = NULL;
	if (cli != NULL){
		key_datum = gdbm_firstkey(data->gdbm);
		while(key_datum.dptr){
			data_datum = gdbm_fetch(data->gdbm, key_datum);
			if (data_datum.dptr){
				memcpy(&entry,data_datum.dptr, sizeof(ippool_info));
				free(data_datum.dptr);
				/*
		 		* If we find an entry for the same caller-id with active=1
		 		* then we use that for multilink (MPPP) to work properly.
		 		*/
				if (strcmp(entry.cli,cli) == 0 && entry.active){
					mppp = 1;
					break;
				}
			}
			nextkey = gdbm_nextkey(data->gdbm, key_datum);
			free(key_datum.dptr);
			key_datum = nextkey;
		}
	}

	if (key_datum.dptr == NULL){
		key_datum = gdbm_firstkey(data->gdbm);
		while(key_datum.dptr){
			data_datum = gdbm_fetch(data->gdbm, key_datum);
			if (data_datum.dptr){
				memcpy(&entry,data_datum.dptr, sizeof(ippool_info));
				free(data_datum.dptr);

				/*
				 * Find an entry with active == 0
				 * or an entry that has expired
				 */
				if (entry.active == 0 || (entry.timestamp && ((entry.timeout &&
				request->timestamp >= (entry.timestamp + entry.timeout)) ||
				(data->max_timeout && request->timestamp >= (entry.timestamp + data->max_timeout))))){
					datum tmp;

					tmp.dptr = (char *) &entry.ipaddr;
					tmp.dsize = sizeof(uint32_t);
					data_datum = gdbm_fetch(data->ip, tmp);

					/*
					 * If we find an entry in the ip index and the number is zero (meaning
					 * that we haven't allocated the same ip address to another nas/port pair)
					 * or if we don't find an entry then delete the session entry so
					 * that we can change the key
					 * Else we don't delete the session entry since we haven't yet deallocated the
					 * corresponding ip address and we continue our search.
					 */

					if (data_datum.dptr){
						memcpy(&num,data_datum.dptr, sizeof(int));
						free(data_datum.dptr);
						if (num == 0){
							delete = 1;
							break;
						}
					}
					else{
						delete = 1;
						break;
					}
				}
			}
			nextkey = gdbm_nextkey(data->gdbm, key_datum);
			free(key_datum.dptr);
			key_datum = nextkey;
		}
	}
	/*
	 * If we have found a free entry set active to 1 then add a Framed-IP-Address attribute to
	 * the reply
	 * We keep the operation mutex locked until after we have set the corresponding entry active
	 */
	if (key_datum.dptr){
		if (found && !mppp){
			/*
			 * Found == 1 means we have the nas/port combination entry in our database
			 * We exchange the ip address between the nas/port entry and the free entry
			 * Afterwards we will save the free ip address to the nas/port entry.
			 * That is:
			 *  ---------------------------------------------
			 *  - NAS/PORT Entry  |||| Free Entry  ||| Time
			 *  -    IP1                 IP2(Free)    BEFORE
			 *  -    IP2(Free)           IP1          AFTER
			 *  ---------------------------------------------
			 *
			 * We only do this if we are NOT doing MPPP
			 *
			 */
			datum key_datum_tmp;
			datum data_datum_tmp;
			ippool_key key_tmp;

			memcpy(key_tmp.key,key_str,16);
			key_datum_tmp.dptr = (char *) &key_tmp;
			key_datum_tmp.dsize = sizeof(ippool_key);

			data_datum_tmp = gdbm_fetch(data->gdbm, key_datum_tmp);
			if (data_datum_tmp.dptr != NULL){

				rcode = gdbm_store(data->gdbm, key_datum, data_datum_tmp, GDBM_REPLACE);
				free(data_datum_tmp.dptr);
				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;
				}
			}
		}
		else{
			/*
			 * We have not found the nas/port combination
			 */
			if (delete){
				/*
		 	  	 * Delete the entry so that we can change the key
			 	 * All is well. We delete one entry and we add one entry
		 	 	 */
				gdbm_delete(data->gdbm, key_datum);
			}
			else{
				/*
				 * We are doing MPPP. (mppp should be 1)
				 * We don't do anything.
				 * We will create an extra not needed entry in the database in this case
				 * but we don't really care since we always also use the ip_index database
				 * when we search for a free entry.
				 * We will also delete that entry on the accounting section so that we only
				 * have one nas/port entry referencing each ip
				 */
				if (mppp)
					extra = 1;
				if (!mppp)
					radlog(L_ERR, "rlm_ippool: mppp is not one. Please report this behaviour.");
			}
		}
		free(key_datum.dptr);
		entry.active = 1;
		entry.timestamp = request->timestamp;
		if ((vp = pairfind(request->reply->vps, PW_SESSION_TIMEOUT)) != NULL)
			entry.timeout = (time_t) vp->vp_integer;
		else
			entry.timeout = 0;
		if (extra)
			entry.extra = 1;
		data_datum.dptr = (char *) &entry;
		data_datum.dsize = sizeof(ippool_info);
		memcpy(key.key, key_str, 16);
		key_datum.dptr = (char *) &key;
		key_datum.dsize = sizeof(ippool_key);

		DEBUG2("rlm_ippool: Allocating ip to key: '%s'",hex_str);
		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;
		}

		/* Increase the ip index count */
		key_datum.dptr = (char *) &entry.ipaddr;
		key_datum.dsize = sizeof(uint32_t);
		data_datum = gdbm_fetch(data->ip, key_datum);
		if (data_datum.dptr){
			memcpy(&num,data_datum.dptr,sizeof(int));
			free(data_datum.dptr);
		} else
			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;
		}
		pthread_mutex_unlock(&data->op_mutex);


		DEBUG("rlm_ippool: Allocated ip %s to client key: %s",ip_ntoa(str,entry.ipaddr),hex_str);
		vp = radius_paircreate(request, &request->reply->vps,
				       PW_FRAMED_IP_ADDRESS, PW_TYPE_IPADDR);
		vp->vp_ipaddr = entry.ipaddr;

		/*
		 *	If there is no Framed-Netmask attribute in the
		 *	reply, add one
		 */
		if (pairfind(request->reply->vps, PW_FRAMED_IP_NETMASK) == NULL) {
			vp = radius_paircreate(request, &request->reply->vps,
					       PW_FRAMED_IP_NETMASK,
					       PW_TYPE_IPADDR);
			vp->vp_ipaddr = ntohl(data->netmask);
		}

	}
	else{
		pthread_mutex_unlock(&data->op_mutex);
		DEBUG("rlm_ippool: No available ip addresses in pool.");
		return RLM_MODULE_NOTFOUND;
	}

	return RLM_MODULE_OK;
}

static int ippool_detach(void *instance)
{
	rlm_ippool_t *data = (rlm_ippool_t *) instance;

	gdbm_close(data->gdbm);
	gdbm_close(data->ip);
	pthread_mutex_destroy(&data->op_mutex);

	free(instance);
	return 0;
}

/*
 *	The module name should be the only globally exported symbol.
 *	That is, everything else should be 'static'.
 *
 *	If the module needs to temporarily modify it's instantiation
 *	data, the type should be changed to RLM_TYPE_THREAD_UNSAFE.
 *	The server will then take care of ensuring that the module
 *	is single-threaded.
 */
module_t rlm_ippool = {
	RLM_MODULE_INIT,
	"ippool",
	RLM_TYPE_THREAD_SAFE,		/* type */
	ippool_instantiate,		/* instantiation */
	ippool_detach,			/* detach */
	{
		NULL,			/* authentication */
		NULL,		 	/* authorization */
		NULL,			/* preaccounting */
		ippool_accounting,	/* accounting */
		NULL,			/* checksimul */
		NULL,			/* pre-proxy */
		NULL,			/* post-proxy */
		ippool_postauth		/* post-auth */
	},
};