Differential D24232 Diff 70089 sys/net/route/route_ctl.c

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sys/net/route/route_ctl.c

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				/*-
				* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
				*
				* Copyright (c) 2020 Alexander V. Chernikov
				*
				* 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.
				*
				* $FreeBSD$
				*/

				#include "opt_inet.h"
				#include "opt_inet6.h"

				#include <sys/param.h>
				#include <sys/systm.h>
				#include <sys/malloc.h>
				#include <sys/mbuf.h>
				#include <sys/socket.h>
				#include <sys/sysctl.h>
				#include <sys/syslog.h>
				#include <sys/kernel.h>
				#include <sys/lock.h>
				#include <sys/rmlock.h>

				#include <net/if.h>
				#include <net/if_var.h>
				#include <net/if_dl.h>
				#include <net/vnet.h>
				#include <net/route.h>
				#include <net/route_var.h>
				#include <net/route/nhop_utils.h>
				#include <net/route/nhop.h>
				#include <net/route/nhop_var.h>
				#include <net/route/shared.h>
				#include <netinet/in.h>

				#include <vm/uma.h>


				/*
				* This file contains control plane routing tables functions.
				*
				* All functions assumes they are called in net epoch.
				*/

				static void set_req_mtu(const struct rt_addrinfo info, struct nhop_request req);

				static void fill_nh_request(struct rib_head rnh, struct rt_addrinfo info,
				struct nhop_request *nh_req);
				static void fill_nh_request_from_nhop(const struct nhop_object *nh,
				struct sockaddr_storage gw_storage, struct nhop_request nh_req);


				/*
				* Sets @nh_req mtu data based on the @info data.
				*/
				static void
				set_req_mtu(const struct rt_addrinfo info, struct nhop_request nh_req)
				{

				if (info->rti_mflags & RTV_MTU) {
				if (info->rti_rmx->rmx_mtu != 0) {

				/*
				* MTU was explicitly provided by user.
				* Keep it.
				*/
				nh_req->rt_flags \|= RTF_FIXEDMTU;
				} else {

				/*
				* User explicitly sets MTU to 0.
				* Assume rollback to default.
				*/
				nh_req->rt_flags &= ~RTF_FIXEDMTU;
				}
				nh_req->mtu = info->rti_rmx->rmx_mtu;
				}
				}


				/*
				* Fills @nh_req based on the data provided in @info.
				*/
				static void
				fill_nh_request(struct rib_head rnh, struct rt_addrinfo info,
				struct nhop_request *nh_req)
				{

				bzero(nh_req, sizeof(struct nhop_request));
				nh_req->ifp = info->rti_ifa->ifa_ifp;
				nh_req->ifa = info->rti_ifa;
				nh_req->gw = info->rti_info[RTAX_GATEWAY];
				nh_req->family = info->rti_info[RTAX_DST]->sa_family;
				nh_req->rt_flags = info->rti_flags; // fill original rt flags
				nh_req->nh_type = 0; // hook responsibility to set nhop type
				set_req_mtu(info, nh_req);
				}

				/*
				* Fill @nh_req based on the real @nh.
				*/
				static void
				fill_nh_request_from_nhop(const struct nhop_object *nh,
				struct sockaddr_storage gw_storage, struct nhop_request nh_req)
				{

				memset(nh_req, 0, sizeof(struct nhop_request));
				aeUnsubmitted Done Inline Actions It would be better use something one - memset or bzero :) ae: It would be better use something one - memset or bzero :)
				nh_req->ifp = nh->nh_ifp;
				nh_req->ifa = nh->nh_ifa;
				nh_req->family = nh->nh_priv->nh_family;
				nh_req->mtu = nh->nh_mtu;
				nh_req->rt_flags = nh->nh_priv->rt_flags;
				nh_req->nh_type = nh->nh_priv->nh_type;

				if (nh_req->rt_flags & RTF_GATEWAY) {
				/* Assume size is already validated */
				memcpy(gw_storage, &nh->gw4_sa, nh->gw4_sa.sin_len);
				aeUnsubmitted Done Inline Actions IMHO, using gw_sa and sa_len is preferable. It mean address family independence. ae: IMHO, using gw_sa and sa_len is preferable. It mean address family independence.
				} else {
				/* Nhop value is largerly ignored, set some random bits */
				gw_storage->ss_len = 0;
				}
				nh_req->gw = (struct sockaddr *)gw_storage;
				}

				/*
				* Update @nh_req request data based on the parameters supplied in @info.
				* This is a helper function to support route changes.
				*
				* It limits the changes that can be done to the route to the following:
				* 1) all combination of gateway changes (gw, interface, blackhole/reject)
				* 2) route flags (FLAG[123],STATIC,BLACKHOLE,REJECT)
				* 3) route MTU
				*
				* Assumes nh_req gw pointer has sockaddr_storage-sized pointer supplied
				*
				* Returns:
				* 0 on success
				*/
				static int
				alter_nh_request(struct rt_addrinfo info, u_int fibnum, struct nhop_request nh_req)
				{

				/* Update MTU if set in the request*/
				set_req_mtu(info, nh_req);

				/* XXX: allow only one of BLACKHOLE,REJECT,GATEWAY */

				/* Allow some flags (FLAG1,STATIC,BLACKHOLE,REJECT) to be toggled on change. */
				nh_req->rt_flags &= ~RTF_FMASK;
				nh_req->rt_flags \|= info->rti_flags & RTF_FMASK;

				/* Consider gateway change */
				struct sockaddr *info_gw = info->rti_info[RTAX_GATEWAY];
				if (info_gw != NULL) {
				nh_req->gw = info_gw;
				/* Update RTF_GATEWAY flag status */
				nh_req->rt_flags &= ~RTF_GATEWAY;
				nh_req->rt_flags \|= (RTF_GATEWAY & info->rti_flags);
				}

				if (info->rti_ifa != NULL)
				nh_req->ifa = info->rti_ifa;
				if (info->rti_ifp != NULL)
				nh_req->ifp = info->rti_ifp;

				return (0);
				}

				/*
				* Creates a new nexthop based on the information in @info.
				*
				* Returns:
				* 0 on success, filling @nh_ret with the desired nexthop object ptr
				* errno otherwise
				*/
				int
				create_nhop_from_info(struct rib_head rnh, struct rt_addrinfo info,
				struct nhop_object **nh_ret)
				{
				struct sockaddr gateway, dst, *netmask;
				struct nhop_request nh_req;
				int error;

				NET_EPOCH_ASSERT();

				fill_nh_request(rnh, info, &nh_req);

				/* Give the protocols chance to augment the request data */
				dst = info->rti_info[RTAX_DST];
				netmask = info->rti_info[RTAX_NETMASK];
				gateway = info->rti_info[RTAX_GATEWAY];

				if (rnh->rnh_preadd != NULL) {
				error = rnh->rnh_preadd(rnh->rib_fibnum, dst, netmask, &nh_req);
				if (error != 0)
				return (error);
				}

				*nh_ret = nhop_get(rnh, &nh_req);
				if (*nh_ret == NULL) {
				DPRINTF("failed to get the nexthop from req");
				return (ENOBUFS);
				}

				return (0);
				}

				/*
				* Creates new nexthop based on @nh_old and augmentation data from @info.
				* Helper function used in the route changes, please see
				* alter_nh_request() comments for more details.
				*
				* Returns:
				* 0 on success, filling @nh_ret with the desired nexthop object
				* errno otherwise
				*/
				int
				create_nhop_from_nhop(struct rib_head rnh, const struct nhop_object nh_old,
				struct rt_addrinfo info, struct nhop_object *nh_ret)
				{
				struct nhop_request nh_req;
				struct sockaddr_storage gw_storage;
				int error;

				NET_EPOCH_ASSERT();

				/* Start with copying data from original nexthop */
				fill_nh_request_from_nhop(nh_old, &gw_storage, &nh_req);

				error = alter_nh_request(info, rnh->rib_fibnum, &nh_req);
				if (error != 0)
				return (error);

				/* Give protocol chance to alter the nexthop request */
				if (rnh->rnh_preadd != NULL) {
				error = rnh->rnh_preadd(rnh->rib_fibnum, info->rti_info[RTAX_DST],
				info->rti_info[RTAX_NETMASK], &nh_req);
				if (error != 0) {
				DPRINTF("failed to create nhop: prehook returned %d",
				error);
				return (error);
				}
				}

				*nh_ret = nhop_get(rnh, &nh_req);
				if (*nh_ret == NULL) {
				DPRINTF("failed to create nhop: nhop_get() failed");
				return (EAGAIN);
				}

				return (0);
				}