freebsd/sys/netgraph/netflow/ng_netflow.c

/*-
 * Copyright (c) 2004 Gleb Smirnoff <glebius@FreeBSD.org>
 * Copyright (c) 2001-2003 Roman V. Palagin <romanp@unshadow.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $SourceForge: ng_netflow.c,v 1.30 2004/09/05 11:37:43 glebius Exp $
 */

static const char rcs_id[] =
    "@(#) $FreeBSD$";

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <sys/ctype.h>

#include <net/if.h>
#include <net/ethernet.h>
#include <net/if_arp.h>
#include <net/if_var.h>
#include <net/bpf.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>

#include <netgraph/ng_message.h>
#include <netgraph/ng_parse.h>
#include <netgraph/netgraph.h>
#include <netgraph/netflow/netflow.h>
#include <netgraph/netflow/ng_netflow.h>

/* Netgraph methods */
static ng_constructor_t	ng_netflow_constructor;
static ng_rcvmsg_t	ng_netflow_rcvmsg;
static ng_close_t	ng_netflow_close;
static ng_shutdown_t	ng_netflow_rmnode;
static ng_newhook_t	ng_netflow_newhook;
static ng_rcvdata_t	ng_netflow_rcvdata;
static ng_disconnect_t	ng_netflow_disconnect;

/* Parse type for struct ng_netflow_info */
static const struct ng_parse_struct_field ng_netflow_info_type_fields[]
	= NG_NETFLOW_INFO_TYPE;
static const struct ng_parse_type ng_netflow_info_type = {
	&ng_parse_struct_type,
	&ng_netflow_info_type_fields
};

/*  Parse type for struct ng_netflow_ifinfo */
static const struct ng_parse_struct_field ng_netflow_ifinfo_type_fields[]
	= NG_NETFLOW_IFINFO_TYPE;
static const struct ng_parse_type ng_netflow_ifinfo_type = {
	&ng_parse_struct_type,
	&ng_netflow_ifinfo_type_fields
};

/* Parse type for struct ng_netflow_setdlt */
static const struct ng_parse_struct_field ng_netflow_setdlt_type_fields[]
	= NG_NETFLOW_SETDLT_TYPE;
static const struct ng_parse_type ng_netflow_setdlt_type = {
	&ng_parse_struct_type,
	&ng_netflow_setdlt_type_fields
};

/* Parse type for ng_netflow_setifindex */
static const struct ng_parse_struct_field ng_netflow_setifindex_type_fields[]
	= NG_NETFLOW_SETIFINDEX_TYPE;
static const struct ng_parse_type ng_netflow_setifindex_type = {
	&ng_parse_struct_type,
	&ng_netflow_setifindex_type_fields
};

/* Parse type for ng_netflow_settimeouts */
static const struct ng_parse_struct_field ng_netflow_settimeouts_type_fields[]
	= NG_NETFLOW_SETTIMEOUTS_TYPE;
static const struct ng_parse_type ng_netflow_settimeouts_type = {
	&ng_parse_struct_type,
	&ng_netflow_settimeouts_type_fields
};

/* List of commands and how to convert arguments to/from ASCII */
static const struct ng_cmdlist ng_netflow_cmds[] = {
       {
	 NGM_NETFLOW_COOKIE,
	 NGM_NETFLOW_INFO,
	 "info",
	 NULL,
	 &ng_netflow_info_type
       },
       {
	NGM_NETFLOW_COOKIE,
	NGM_NETFLOW_IFINFO,
	"ifinfo",
	&ng_parse_uint16_type,
	&ng_netflow_ifinfo_type
       },
       {
	NGM_NETFLOW_COOKIE,
	NGM_NETFLOW_SETDLT,
	"setdlt",
	&ng_netflow_setdlt_type,
	NULL
       },
       {
	NGM_NETFLOW_COOKIE,
	NGM_NETFLOW_SETIFINDEX,
	"setifindex",
	&ng_netflow_setifindex_type,
	NULL
       },
       {
	NGM_NETFLOW_COOKIE,
	NGM_NETFLOW_SETTIMEOUTS,
	"settimeouts",
	&ng_netflow_settimeouts_type,
	NULL
       },
       { 0 }
};


/* Netgraph node type descriptor */
static struct ng_type ng_netflow_typestruct = {
	.version =	NG_ABI_VERSION,
	.name =		NG_NETFLOW_NODE_TYPE,
	.constructor =	ng_netflow_constructor,
	.rcvmsg =	ng_netflow_rcvmsg,
	.close =	ng_netflow_close,
	.shutdown =	ng_netflow_rmnode,
	.newhook =	ng_netflow_newhook,
	.rcvdata =	ng_netflow_rcvdata,
	.disconnect =	ng_netflow_disconnect,
	.cmdlist =	ng_netflow_cmds,
};
NETGRAPH_INIT(netflow, &ng_netflow_typestruct);

/* Called at node creation */
static int
ng_netflow_constructor (node_p node)
{
	priv_p priv;
	int error = 0;

	/* Initialize private data */
	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT);
	if (priv == NULL)
		return (ENOMEM);
	bzero(priv, sizeof(*priv));

	/* Make node and its data point at each other */
	NG_NODE_SET_PRIVATE(node, priv);
	priv->node = node;

	/* Initialize timeouts to default values */
	priv->info.nfinfo_inact_t = INACTIVE_TIMEOUT;
	priv->info.nfinfo_act_t = ACTIVE_TIMEOUT;

	/* Initialize callout handle */
	callout_init(&priv->exp_callout, 1);

	/* Allocate memory and set up flow cache */
	if ((error = ng_netflow_cache_init(priv)))
		return (error);

	priv->dgram.header.version = htons(NETFLOW_V5);

	return (0);
}

/*
 * ng_netflow supports two hooks: data and export.
 * Incoming traffic is expected on data, and expired
 * netflow datagrams are sent to export.
 */
static int
ng_netflow_newhook(node_p node, hook_p hook, const char *name)
{
	const priv_p priv = NG_NODE_PRIVATE(node);

	if (strncmp(name, NG_NETFLOW_HOOK_DATA,	/* an iface hook? */
	    strlen(NG_NETFLOW_HOOK_DATA)) == 0) {
		iface_p iface;
		int ifnum = -1;
		const char *cp;
		char *eptr;

		cp = name + strlen(NG_NETFLOW_HOOK_DATA);
		if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
			return (EINVAL);

		ifnum = (int)strtoul(cp, &eptr, 10);
		if (*eptr != '\0' || ifnum < 0 || ifnum >= NG_NETFLOW_MAXIFACES)
			return (EINVAL);

		/* See if hook is already connected */
		if (priv->ifaces[ifnum].hook != NULL)
			return (EISCONN);

		iface = &priv->ifaces[ifnum];

		/* Link private info and hook together */
		NG_HOOK_SET_PRIVATE(hook, iface);
		iface->hook = hook;

		/*
		 * In most cases traffic accounting is done on an
		 * Ethernet interface, so default data link type
		 * will be DLT_EN10MB.
		 */
		iface->info.ifinfo_dlt = DLT_EN10MB;

	} else if (strcmp(name, NG_NETFLOW_HOOK_EXPORT) == 0) {

		if (priv->export != NULL)
			return (EISCONN);

		priv->export = hook;

		/* Exporter is ready. Let's schedule expiry. */
		callout_reset(&priv->exp_callout, (1*hz), &ng_netflow_expire,
		    (void *)priv);
	} else
		return (EINVAL);

	return (0);
}

/* Get a netgraph control message. */
static int
ng_netflow_rcvmsg (node_p node, item_p item, hook_p lasthook)
{
	const priv_p priv = NG_NODE_PRIVATE(node);
	struct ng_mesg *resp = NULL;
	int error = 0;
	struct ng_mesg *msg;

	NGI_GET_MSG(item, msg);

	/* Deal with message according to cookie and command */
	switch (msg->header.typecookie) {
	case NGM_NETFLOW_COOKIE:
		switch (msg->header.cmd) {
		case NGM_NETFLOW_INFO:
		{
			struct ng_netflow_info *i;

			NG_MKRESPONSE(resp, msg, sizeof(struct ng_netflow_info),
			    M_NOWAIT);
			i = (struct ng_netflow_info *)resp->data;
			ng_netflow_copyinfo(priv, i);

			break;
		}
		case NGM_NETFLOW_IFINFO:
		{
			struct ng_netflow_ifinfo *i;
			const uint16_t *index;

			if (msg->header.arglen != sizeof(uint16_t))
				 ERROUT(EINVAL);

			index  = (uint16_t *)msg->data;
			if (*index > NG_NETFLOW_MAXIFACES)
				ERROUT(EINVAL);

			/* connected iface? */
			if (priv->ifaces[*index].hook == NULL)
				 ERROUT(EINVAL);

			NG_MKRESPONSE(resp, msg,
			     sizeof(struct ng_netflow_ifinfo), M_NOWAIT);
			i = (struct ng_netflow_ifinfo *)resp->data;
			memcpy((void *)i, (void *)&priv->ifaces[*index].info,
			    sizeof(priv->ifaces[*index].info));

			break;
		}
		case NGM_NETFLOW_SETDLT:
		{
			struct ng_netflow_setdlt *set;
			struct ng_netflow_iface *iface;

			if (msg->header.arglen != sizeof(struct ng_netflow_setdlt))
				ERROUT(EINVAL);

			set = (struct ng_netflow_setdlt *)msg->data;
			if (set->iface > NG_NETFLOW_MAXIFACES)
				ERROUT(EINVAL);
			iface = &priv->ifaces[set->iface];

			/* connected iface? */
			if (iface->hook == NULL)
				ERROUT(EINVAL);

			switch (set->dlt) {
			case	DLT_EN10MB:
				iface->info.ifinfo_dlt = DLT_EN10MB;
				break;
			case	DLT_RAW:
				iface->info.ifinfo_dlt = DLT_RAW;
				break;
			default:
				ERROUT(EINVAL);
			}
			break;
		}
		case NGM_NETFLOW_SETIFINDEX:
		{
			struct ng_netflow_setifindex *set;
			struct ng_netflow_iface *iface;

			if (msg->header.arglen != sizeof(struct ng_netflow_setifindex))
				ERROUT(EINVAL);

			set = (struct ng_netflow_setifindex *)msg->data;
			if (set->iface > NG_NETFLOW_MAXIFACES)
				ERROUT(EINVAL);
			iface = &priv->ifaces[set->iface];

			/* connected iface? */
			if (iface->hook == NULL)
				ERROUT(EINVAL);

			iface->info.ifinfo_index = set->index;

			break;
		}
		case NGM_NETFLOW_SETTIMEOUTS:
		{
			struct ng_netflow_settimeouts *set;

			if (msg->header.arglen != sizeof(struct ng_netflow_settimeouts))
				ERROUT(EINVAL);

			set = (struct ng_netflow_settimeouts *)msg->data;

			priv->info.nfinfo_inact_t = set->inactive_timeout;
			priv->info.nfinfo_act_t = set->active_timeout;

			break;
		}
		case NGM_NETFLOW_SHOW:
		{
			uint32_t *last;

			if (msg->header.arglen != sizeof(uint32_t))
				ERROUT(EINVAL);

			last = (uint32_t *)msg->data;

			NG_MKRESPONSE(resp, msg, NGRESP_SIZE, M_NOWAIT);

			if (!resp)
				ERROUT(ENOMEM);

			error = ng_netflow_flow_show(priv, *last, resp);

			break;
		}
		default:
			ERROUT(EINVAL);		/* unknown command */
			break;
		}
		break;
	default:
		ERROUT(EINVAL);		/* incorrect cookie */
		break;
	}

	/*
	 * Take care of synchronous response, if any.
	 * Free memory and return.
	 */
done:
	NG_RESPOND_MSG(error, node, item, resp);
	NG_FREE_MSG(msg);

	return (error);
}

/* Receive data on hook. */
static int
ng_netflow_rcvdata (hook_p hook, item_p item)
{
	const node_p node = NG_HOOK_NODE(hook);
	const priv_p priv = NG_NODE_PRIVATE(node);
	const iface_p iface = NG_HOOK_PRIVATE(hook);
	struct mbuf *m;
	int error = 0;

	NGI_GET_M(item, m);
	if (hook == priv->export) {
		/*
		 * Data arrived on export hook.
		 * This must not happen.
		 */
		log(LOG_ERR, "ng_netflow: incoming data on export hook!\n");
		ERROUT(EINVAL);
	};

	/* increase counters */
	iface->info.ifinfo_packets++;

	switch (iface->info.ifinfo_dlt) {
	case DLT_EN10MB:	/* Ethernet */
	{
		struct ether_header *eh;
		uint16_t etype;

		if (CHECK_MLEN(m, (sizeof(struct ether_header))))
			ERROUT(EINVAL);

		if (CHECK_PULLUP(m, (sizeof(struct ether_header))))
			ERROUT(ENOBUFS);

		eh = mtod(m, struct ether_header *);

		/* make sure this is IP frame */
		etype = ntohs(eh->ether_type);
		switch (etype) {
		case ETHERTYPE_IP:
			m_adj(m, sizeof(struct ether_header));
			break;
		default:
			ERROUT(EINVAL);	/* ignore this frame */
		}

		break;
	}
	case DLT_RAW:
		break;
	default:
		ERROUT(EINVAL);
		break;
	}

	if (CHECK_MLEN(m, sizeof(struct ip)))
		ERROUT(EINVAL);

	if (CHECK_PULLUP(m, sizeof(struct ip)))
		ERROUT(ENOBUFS);

	error = ng_netflow_flow_add(priv, &m, iface);

done:
	if (m) {
		if (item)
			NG_FREE_ITEM(item);
		NG_FREE_M(m);
	}

	return (error);	
}

/* We will be shut down in a moment */
static int
ng_netflow_close(node_p node)
{
	const priv_p priv = NG_NODE_PRIVATE(node);

	callout_drain(&priv->exp_callout);
	ng_netflow_cache_flush(priv);

	return (0);
}

/* Do local shutdown processing. */
static int
ng_netflow_rmnode(node_p node)
{
	const priv_p priv = NG_NODE_PRIVATE(node);

	NG_NODE_SET_PRIVATE(node, NULL);
	NG_NODE_UNREF(priv->node);

	FREE(priv, M_NETGRAPH);

	return (0);
}

/* Hook disconnection. */
static int
ng_netflow_disconnect(hook_p hook)
{
	node_p node = NG_HOOK_NODE(hook);
	priv_p priv = NG_NODE_PRIVATE(node);
	iface_p iface = NG_HOOK_PRIVATE(hook);

	if (iface != NULL)
		iface->hook = NULL;

	/* if export hook disconnected stop running expire(). */
	if (hook == priv->export) {
		callout_drain(&priv->exp_callout);
		priv->export = NULL;
	}

	/* Removal of the last link destroys the node. */
	if (NG_NODE_NUMHOOKS(node) == 0)
		ng_rmnode_self(node);

	return (0);
}