/*
 * Copyright (c) 2000-2021 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * Copyright 1996 Massachusetts Institute of Technology
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby
 * granted, provided that both the above copyright notice and this
 * permission notice appear in all copies, that both the above
 * copyright notice and this permission notice appear in all
 * supporting documentation, and that the name of M.I.T. not be used
 * in advertising or publicity pertaining to distribution of the
 * software without specific, written prior permission.  M.I.T. makes
 * no representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied
 * warranty.
 *
 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
 * SHALL M.I.T. 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.
 *
 * $FreeBSD: src/sys/net/if_mib.c,v 1.8.2.1 2000/08/03 00:09:34 ps Exp $
 */

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

#include <net/if.h>
#include <net/if_mib.h>
#include <net/if_var.h>
#include <net/net_sysctl.h>

#include <os/log.h>

/*
 * A sysctl(3) MIB for generic interface information.  This information
 * is exported in the net.link.generic branch, which has the following
 * structure:
 *
 * net.link.generic	.system			- system-wide control variables
 *						  and statistics (node)
 *			.ifdata.<ifindex>.general
 *						- what's in `struct ifdata'
 *						  plus some other info
 *			.ifdata.<ifindex>.linkspecific
 *						- a link-type-specific data
 *						  structure (as might be used
 *						  by an SNMP agent
 *
 * Perhaps someday we will make addresses accessible via this interface
 * as well (then there will be four such...).  The reason that the
 * index comes before the last element in the name is because it
 * seems more orthogonal that way, particularly with the possibility
 * of other per-interface data living down here as well (e.g., integrated
 * services stuff).
 */

SYSCTL_DECL(_net_link_generic);

SYSCTL_NODE(_net_link_generic, IFMIB_SYSTEM, system, CTLFLAG_RD | CTLFLAG_LOCKED, 0,
    "Variables global to all interfaces");

static int sysctl_ifdata SYSCTL_HANDLER_ARGS;
SYSCTL_NODE(_net_link_generic, IFMIB_IFDATA, ifdata, CTLFLAG_RD | CTLFLAG_LOCKED,
    sysctl_ifdata, "Interface table");

static int sysctl_ifalldata SYSCTL_HANDLER_ARGS;
SYSCTL_NODE(_net_link_generic, IFMIB_IFALLDATA, ifalldata, CTLFLAG_RD | CTLFLAG_LOCKED,
    sysctl_ifalldata, "Interface table");

static int make_ifmibdata(struct ifnet *, int *__counted_by(2), struct sysctl_req *);
int
make_ifmibdata(struct ifnet *ifp, int *__counted_by(2) name, struct sysctl_req *req)
{
	struct ifmibdata        ifmd;
	int error = 0;

	switch (name[1]) {
	default:
		error = ENOENT;
		break;

	case IFDATA_GENERAL:
		bzero(&ifmd, sizeof(ifmd));
		/*
		 * Make sure the interface is in use
		 */
		if (ifnet_is_fully_attached(ifp)) {
			snprintf(ifmd.ifmd_name, sizeof(ifmd.ifmd_name), "%s",
			    if_name(ifp));

#define COPY(fld) ifmd.ifmd_##fld = ifp->if_##fld
			COPY(pcount);
			COPY(flags);
			if_data_internal_to_if_data64(ifp, &ifp->if_data, &ifmd.ifmd_data);
#undef COPY
			ifmd.ifmd_snd_len = IFCQ_LEN(ifp->if_snd);
			ifmd.ifmd_snd_maxlen = IFCQ_MAXLEN(ifp->if_snd);
			ifmd.ifmd_snd_drops =
			    (unsigned int)ifp->if_snd->ifcq_dropcnt.packets;
		}
		error = SYSCTL_OUT(req, &ifmd, sizeof ifmd);
		if (error || !req->newptr) {
			break;
		}

#ifdef IF_MIB_WR
		error = SYSCTL_IN(req, &ifmd, sizeof ifmd);
		if (error) {
			break;
		}

#define DONTCOPY(fld) ifmd.ifmd_data.ifi_##fld = ifp->if_data.ifi_##fld
		DONTCOPY(type);
		DONTCOPY(physical);
		DONTCOPY(addrlen);
		DONTCOPY(hdrlen);
		DONTCOPY(mtu);
		DONTCOPY(metric);
		DONTCOPY(baudrate);
#undef DONTCOPY
#define COPY(fld) ifp->if_##fld = ifmd.ifmd_##fld
		COPY(data);
		ifp->if_snd->ifq_maxlen = ifmd.ifmd_snd_maxlen;
		ifp->if_snd->ifq_drops = ifmd.ifmd_snd_drops;
#undef COPY
#endif /* IF_MIB_WR */
		break;

	case IFDATA_LINKSPECIFIC:
		error = SYSCTL_OUT(req, ifp->if_linkmib, ifp->if_linkmiblen);
		if (error || !req->newptr) {
			break;
		}

#ifdef IF_MIB_WR
		error = SYSCTL_IN(req, ifp->if_linkmib, ifp->if_linkmiblen);
		if (error) {
			break;
		}
#endif /* IF_MIB_WR */
		break;

	case IFDATA_SUPPLEMENTAL: {
		struct ifmibdata_supplemental *ifmd_supp;

		ifmd_supp = kalloc_type(struct ifmibdata_supplemental,
		    Z_WAITOK_ZERO_NOFAIL);
		if_copy_traffic_class(ifp, &ifmd_supp->ifmd_traffic_class);
		if_copy_data_extended(ifp, &ifmd_supp->ifmd_data_extended);
		if_copy_packet_stats(ifp, &ifmd_supp->ifmd_packet_stats);
		if_copy_rxpoll_stats(ifp, &ifmd_supp->ifmd_rxpoll_stats);
		if_copy_netif_stats(ifp, &ifmd_supp->ifmd_netif_stats);

		if (req->oldptr == USER_ADDR_NULL) {
			req->oldlen = sizeof(*ifmd_supp);
		}

		error = SYSCTL_OUT(req, ifmd_supp, MIN(sizeof(*ifmd_supp),
		    req->oldlen));
#if DEVELOPMENT || DEBUG
		if (error != 0) {
			os_log(OS_LOG_DEFAULT, "%s: IFDATA_SUPPLEMENTAL SYSCTL_OUT(MIN(%lu, %lu) failed with error %d",
			    __func__, sizeof(*ifmd_supp), req->oldlen, error);
		}
#endif /* DEVELOPMENT || DEBUG */

		kfree_type(struct ifmibdata_supplemental, ifmd_supp);
		break;
	}

	case IFDATA_LINKHEURISTICS: {
		struct if_linkheuristics *ifmd_lh;

		ifmd_lh = kalloc_type(struct if_linkheuristics,
		    Z_WAITOK_ZERO_NOFAIL);

		if_copy_link_heuristics_stats(ifp, ifmd_lh);

		if (req->oldptr == USER_ADDR_NULL) {
			req->oldlen = sizeof(struct if_linkheuristics);
		}

		error = SYSCTL_OUT(req, ifmd_lh, MIN(sizeof(struct if_linkheuristics),
		    req->oldlen));

		kfree_type(struct if_linkheuristics, ifmd_lh);
		break;
	}
	}

	return error;
}

int
sysctl_ifdata SYSCTL_HANDLER_ARGS /* XXX bad syntax! */
{
#pragma unused(oidp)
	DECLARE_SYSCTL_HANDLER_ARG_ARRAY(int, 2, name, namelen);
	int error = 0;
	struct ifnet *ifp;

	ifnet_head_lock_shared();
	if (name[0] <= 0 || name[0] > if_index ||
	    (ifp = ifindex2ifnet[name[0]]) == NULL) {
		ifnet_head_done();
		return ENOENT;
	}
	ifnet_reference(ifp);
	ifnet_head_done();

	ifnet_lock_shared(ifp);
	error = make_ifmibdata(ifp, name, req);
	ifnet_lock_done(ifp);

	ifnet_release(ifp);

	return error;
}

int
sysctl_ifalldata SYSCTL_HANDLER_ARGS /* XXX bad syntax! */
{
#pragma unused(oidp)
	DECLARE_SYSCTL_HANDLER_ARG_ARRAY(int, 2, name, namelen);
	int error = 0;
	struct ifnet *ifp;

	ifnet_head_lock_shared();
	TAILQ_FOREACH(ifp, &ifnet_head, if_link) {
		ifnet_lock_shared(ifp);

		error = make_ifmibdata(ifp, name, req);

		ifnet_lock_done(ifp);
		if (error != 0) {
			break;
		}
	}
	ifnet_head_done();
	return error;
}

static int
sysctl_ifindex SYSCTL_HANDLER_ARGS
{
	int error, val = if_index;

	error = sysctl_handle_int(oidp, &val, 0, req);
	if (error || !req->newptr) {
		return error;
	}

	return 0;
}

SYSCTL_PROC( _net_link_generic_system, IFMIB_IFCOUNT, ifcount,
    CTLFLAG_RD | CTLFLAG_LOCKED,
    NULL, 0, sysctl_ifindex, "Number of configured interfaces",
    "");
