net/ipv6/xfrm6_policy.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * xfrm6_policy.c: based on xfrm4_policy.c
  *
  * Authors:
  *	Mitsuru KANDA @USAGI
  *	Kazunori MIYAZAWA @USAGI
  *	Kunihiro Ishiguro <kunihiro@ipinfusion.com>
  *		IPv6 support
  *	YOSHIFUJI Hideaki
  *		Split up af-specific portion
  *
  */

 #include <linux/err.h>
 #include <linux/kernel.h>
 #include <linux/netdevice.h>
 #include <net/addrconf.h>
 #include <net/dst.h>
 #include <net/xfrm.h>
 #include <net/ip.h>
 #include <net/ipv6.h>
 #include <net/ip6_route.h>
 #include <net/l3mdev.h>

 static struct dst_entry *xfrm6_dst_lookup(const struct xfrm_dst_lookup_params *params)
 {
 	struct flowi6 fl6;
 	struct dst_entry *dst;
 	int err;

 	memset(&fl6, 0, sizeof(fl6));
 	fl6.flowi6_l3mdev = l3mdev_master_ifindex_by_index(params->net,
 							   params->oif);
 	fl6.flowi6_mark = params->mark;
 	memcpy(&fl6.daddr, params->daddr, sizeof(fl6.daddr));
 	if (params->saddr)
 		memcpy(&fl6.saddr, params->saddr, sizeof(fl6.saddr));

 	fl6.flowi4_proto = params->ipproto;
 	fl6.uli = params->uli;

 	dst = ip6_route_output(params->net, NULL, &fl6);

 	err = dst->error;
 	if (dst->error) {
 		dst_release(dst);
 		dst = ERR_PTR(err);
 	}

 	return dst;
 }

 static int xfrm6_get_saddr(xfrm_address_t *saddr,
 			   const struct xfrm_dst_lookup_params *params)
 {
 	struct dst_entry *dst;
 	struct net_device *dev;
 	struct inet6_dev *idev;

 	dst = xfrm6_dst_lookup(params);
 	if (IS_ERR(dst))
 		return -EHOSTUNREACH;

 	idev = ip6_dst_idev(dst);
 	if (!idev) {
 		dst_release(dst);
 		return -EHOSTUNREACH;
 	}
 	dev = idev->dev;
 	ipv6_dev_get_saddr(dev_net(dev), dev, &params->daddr->in6, 0,
 			   &saddr->in6);
 	dst_release(dst);
 	return 0;
 }

 static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
 			  const struct flowi *fl)
 {
 	struct rt6_info *rt = dst_rt6_info(xdst->route);

 	xdst->u.dst.dev = dev;
 	netdev_hold(dev, &xdst->u.dst.dev_tracker, GFP_ATOMIC);

 	xdst->u.rt6.rt6i_idev = in6_dev_get(dev);
 	if (!xdst->u.rt6.rt6i_idev) {
 		netdev_put(dev, &xdst->u.dst.dev_tracker);
 		return -ENODEV;
 	}

 	/* Sheit... I remember I did this right. Apparently,
 	 * it was magically lost, so this code needs audit */
 	xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST |
 						   RTF_LOCAL);
 	xdst->route_cookie = rt6_get_cookie(rt);
 	xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway;
 	xdst->u.rt6.rt6i_dst = rt->rt6i_dst;
 	xdst->u.rt6.rt6i_src = rt->rt6i_src;
 	rt6_uncached_list_add(&xdst->u.rt6);

 	return 0;
 }

 static void xfrm6_update_pmtu(struct dst_entry *dst, struct sock *sk,
 			      struct sk_buff *skb, u32 mtu,
 			      bool confirm_neigh)
 {
 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
 	struct dst_entry *path = xdst->route;

 	path->ops->update_pmtu(path, sk, skb, mtu, confirm_neigh);
 }

 static void xfrm6_redirect(struct dst_entry *dst, struct sock *sk,
 			   struct sk_buff *skb)
 {
 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
 	struct dst_entry *path = xdst->route;

 	path->ops->redirect(path, sk, skb);
 }

 static void xfrm6_dst_destroy(struct dst_entry *dst)
 {
 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;

 	dst_destroy_metrics_generic(dst);
 	rt6_uncached_list_del(&xdst->u.rt6);
 	if (likely(xdst->u.rt6.rt6i_idev))
 		in6_dev_put(xdst->u.rt6.rt6i_idev);
 	xfrm_dst_destroy(xdst);
 }

 static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
 {
 	struct xfrm_dst *xdst;

 	xdst = (struct xfrm_dst *)dst;
 	if (xdst->u.rt6.rt6i_idev->dev == dev) {
 		struct inet6_dev *loopback_idev =
 			in6_dev_get(dev_net(dev)->loopback_dev);

 		do {
 			in6_dev_put(xdst->u.rt6.rt6i_idev);
 			xdst->u.rt6.rt6i_idev = loopback_idev;
 			in6_dev_hold(loopback_idev);
 			xdst = (struct xfrm_dst *)xfrm_dst_child(&xdst->u.dst);
 		} while (xdst->u.dst.xfrm);

 		__in6_dev_put(loopback_idev);
 	}

 	xfrm_dst_ifdown(dst, dev);
 }

 static struct dst_ops xfrm6_dst_ops_template = {
 	.family =		AF_INET6,
 	.update_pmtu =		xfrm6_update_pmtu,
 	.redirect =		xfrm6_redirect,
 	.cow_metrics =		dst_cow_metrics_generic,
 	.destroy =		xfrm6_dst_destroy,
 	.ifdown =		xfrm6_dst_ifdown,
 	.local_out =		__ip6_local_out,
 	.gc_thresh =		32768,
 };

 static const struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
 	.dst_ops =		&xfrm6_dst_ops_template,
 	.dst_lookup =		xfrm6_dst_lookup,
 	.get_saddr =		xfrm6_get_saddr,
 	.fill_dst =		xfrm6_fill_dst,
 	.blackhole_route =	ip6_blackhole_route,
 };

 static int __init xfrm6_policy_init(void)
 {
 	return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo, AF_INET6);
 }

 static void xfrm6_policy_fini(void)
 {
 	xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
 }

 #ifdef CONFIG_SYSCTL
 static struct ctl_table xfrm6_policy_table[] = {
 	{
 		.procname       = "xfrm6_gc_thresh",
 		.data		= &init_net.xfrm.xfrm6_dst_ops.gc_thresh,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler   = proc_dointvec,
 	},
 };

 static int __net_init xfrm6_net_sysctl_init(struct net *net)
 {
 	struct ctl_table *table;
 	struct ctl_table_header *hdr;

 	table = xfrm6_policy_table;
 	if (!net_eq(net, &init_net)) {
 		table = kmemdup(table, sizeof(xfrm6_policy_table), GFP_KERNEL);
 		if (!table)
 			goto err_alloc;

 		table[0].data = &net->xfrm.xfrm6_dst_ops.gc_thresh;
 	}

 	hdr = register_net_sysctl_sz(net, "net/ipv6", table,
 				     ARRAY_SIZE(xfrm6_policy_table));
 	if (!hdr)
 		goto err_reg;

 	net->ipv6.sysctl.xfrm6_hdr = hdr;
 	return 0;

 err_reg:
 	if (!net_eq(net, &init_net))
 		kfree(table);
 err_alloc:
 	return -ENOMEM;
 }

 static void __net_exit xfrm6_net_sysctl_exit(struct net *net)
 {
 	const struct ctl_table *table;

 	if (!net->ipv6.sysctl.xfrm6_hdr)
 		return;

 	table = net->ipv6.sysctl.xfrm6_hdr->ctl_table_arg;
 	unregister_net_sysctl_table(net->ipv6.sysctl.xfrm6_hdr);
 	if (!net_eq(net, &init_net))
 		kfree(table);
 }
 #else /* CONFIG_SYSCTL */
 static inline int xfrm6_net_sysctl_init(struct net *net)
 {
 	return 0;
 }

 static inline void xfrm6_net_sysctl_exit(struct net *net)
 {
 }
 #endif

 static int __net_init xfrm6_net_init(struct net *net)
 {
 	int ret;

 	memcpy(&net->xfrm.xfrm6_dst_ops, &xfrm6_dst_ops_template,
 	       sizeof(xfrm6_dst_ops_template));
 	ret = dst_entries_init(&net->xfrm.xfrm6_dst_ops);
 	if (ret)
 		return ret;

 	ret = xfrm6_net_sysctl_init(net);
 	if (ret)
 		dst_entries_destroy(&net->xfrm.xfrm6_dst_ops);

 	return ret;
 }

 static void __net_exit xfrm6_net_exit(struct net *net)
 {
 	xfrm6_net_sysctl_exit(net);
 	dst_entries_destroy(&net->xfrm.xfrm6_dst_ops);
 }

 static struct pernet_operations xfrm6_net_ops = {
 	.init	= xfrm6_net_init,
 	.exit	= xfrm6_net_exit,
 };

 int __init xfrm6_init(void)
 {
 	int ret;

 	ret = xfrm6_policy_init();
 	if (ret)
 		goto out;
 	ret = xfrm6_state_init();
 	if (ret)
 		goto out_policy;

 	ret = xfrm6_protocol_init();
 	if (ret)
 		goto out_state;

 	ret = register_pernet_subsys(&xfrm6_net_ops);
 	if (ret)
 		goto out_protocol;

 	ret = xfrm_nat_keepalive_init(AF_INET6);
 	if (ret)
 		goto out_nat_keepalive;
 out:
 	return ret;
 out_nat_keepalive:
 	unregister_pernet_subsys(&xfrm6_net_ops);
 out_protocol:
 	xfrm6_protocol_fini();
 out_state:
 	xfrm6_state_fini();
 out_policy:
 	xfrm6_policy_fini();
 	goto out;
 }

 void xfrm6_fini(void)
 {
 	xfrm_nat_keepalive_fini(AF_INET6);
 	unregister_pernet_subsys(&xfrm6_net_ops);
 	xfrm6_protocol_fini();
 	xfrm6_policy_fini();
 	xfrm6_state_fini();
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* xfrm6_policy.c: based on xfrm4_policy.c
	*
	* Authors:
	* Mitsuru KANDA @USAGI
	* Kazunori MIYAZAWA @USAGI
	* Kunihiro Ishiguro <kunihiro@ipinfusion.com>
	* IPv6 support
	* YOSHIFUJI Hideaki
	* Split up af-specific portion
	*
	*/

	#include <linux/err.h>
	#include <linux/kernel.h>
	#include <linux/netdevice.h>
	#include <net/addrconf.h>
	#include <net/dst.h>
	#include <net/xfrm.h>
	#include <net/ip.h>
	#include <net/ipv6.h>
	#include <net/ip6_route.h>
	#include <net/l3mdev.h>

	static struct dst_entry xfrm6_dst_lookup(const struct xfrm_dst_lookup_params params)
	{
	struct flowi6 fl6;
	struct dst_entry *dst;
	int err;

	memset(&fl6, 0, sizeof(fl6));
	fl6.flowi6_l3mdev = l3mdev_master_ifindex_by_index(params->net,
	params->oif);
	fl6.flowi6_mark = params->mark;
	memcpy(&fl6.daddr, params->daddr, sizeof(fl6.daddr));
	if (params->saddr)
	memcpy(&fl6.saddr, params->saddr, sizeof(fl6.saddr));

	fl6.flowi4_proto = params->ipproto;
	fl6.uli = params->uli;

	dst = ip6_route_output(params->net, NULL, &fl6);

	err = dst->error;
	if (dst->error) {
	dst_release(dst);
	dst = ERR_PTR(err);
	}

	return dst;
	}

	static int xfrm6_get_saddr(xfrm_address_t *saddr,
	const struct xfrm_dst_lookup_params *params)
	{
	struct dst_entry *dst;
	struct net_device *dev;
	struct inet6_dev *idev;

	dst = xfrm6_dst_lookup(params);
	if (IS_ERR(dst))
	return -EHOSTUNREACH;

	idev = ip6_dst_idev(dst);
	if (!idev) {
	dst_release(dst);
	return -EHOSTUNREACH;
	}
	dev = idev->dev;
	ipv6_dev_get_saddr(dev_net(dev), dev, &params->daddr->in6, 0,
	&saddr->in6);
	dst_release(dst);
	return 0;
	}

	static int xfrm6_fill_dst(struct xfrm_dst xdst, struct net_device dev,
	const struct flowi *fl)
	{
	struct rt6_info *rt = dst_rt6_info(xdst->route);

	xdst->u.dst.dev = dev;
	netdev_hold(dev, &xdst->u.dst.dev_tracker, GFP_ATOMIC);

	xdst->u.rt6.rt6i_idev = in6_dev_get(dev);
	if (!xdst->u.rt6.rt6i_idev) {
	netdev_put(dev, &xdst->u.dst.dev_tracker);
	return -ENODEV;
	}

	/* Sheit... I remember I did this right. Apparently,
	* it was magically lost, so this code needs audit */
	xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST \|
	RTF_LOCAL);
	xdst->route_cookie = rt6_get_cookie(rt);
	xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway;
	xdst->u.rt6.rt6i_dst = rt->rt6i_dst;
	xdst->u.rt6.rt6i_src = rt->rt6i_src;
	rt6_uncached_list_add(&xdst->u.rt6);

	return 0;
	}

	static void xfrm6_update_pmtu(struct dst_entry dst, struct sock sk,
	struct sk_buff *skb, u32 mtu,
	bool confirm_neigh)
	{
	struct xfrm_dst xdst = (struct xfrm_dst )dst;
	struct dst_entry *path = xdst->route;

	path->ops->update_pmtu(path, sk, skb, mtu, confirm_neigh);
	}

	static void xfrm6_redirect(struct dst_entry dst, struct sock sk,
	struct sk_buff *skb)
	{
	struct xfrm_dst xdst = (struct xfrm_dst )dst;
	struct dst_entry *path = xdst->route;

	path->ops->redirect(path, sk, skb);
	}

	static void xfrm6_dst_destroy(struct dst_entry *dst)
	{
	struct xfrm_dst xdst = (struct xfrm_dst )dst;

	dst_destroy_metrics_generic(dst);
	rt6_uncached_list_del(&xdst->u.rt6);
	if (likely(xdst->u.rt6.rt6i_idev))
	in6_dev_put(xdst->u.rt6.rt6i_idev);
	xfrm_dst_destroy(xdst);
	}

	static void xfrm6_dst_ifdown(struct dst_entry dst, struct net_device dev)
	{
	struct xfrm_dst *xdst;

	xdst = (struct xfrm_dst *)dst;
	if (xdst->u.rt6.rt6i_idev->dev == dev) {
	struct inet6_dev *loopback_idev =
	in6_dev_get(dev_net(dev)->loopback_dev);

	do {
	in6_dev_put(xdst->u.rt6.rt6i_idev);
	xdst->u.rt6.rt6i_idev = loopback_idev;
	in6_dev_hold(loopback_idev);
	xdst = (struct xfrm_dst *)xfrm_dst_child(&xdst->u.dst);
	} while (xdst->u.dst.xfrm);

	__in6_dev_put(loopback_idev);
	}

	xfrm_dst_ifdown(dst, dev);
	}

	static struct dst_ops xfrm6_dst_ops_template = {
	.family = AF_INET6,
	.update_pmtu = xfrm6_update_pmtu,
	.redirect = xfrm6_redirect,
	.cow_metrics = dst_cow_metrics_generic,
	.destroy = xfrm6_dst_destroy,
	.ifdown = xfrm6_dst_ifdown,
	.local_out = __ip6_local_out,
	.gc_thresh = 32768,
	};

	static const struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
	.dst_ops = &xfrm6_dst_ops_template,
	.dst_lookup = xfrm6_dst_lookup,
	.get_saddr = xfrm6_get_saddr,
	.fill_dst = xfrm6_fill_dst,
	.blackhole_route = ip6_blackhole_route,
	};

	static int __init xfrm6_policy_init(void)
	{
	return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo, AF_INET6);
	}

	static void xfrm6_policy_fini(void)
	{
	xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
	}

	#ifdef CONFIG_SYSCTL
	static struct ctl_table xfrm6_policy_table[] = {
	{
	.procname = "xfrm6_gc_thresh",
	.data = &init_net.xfrm.xfrm6_dst_ops.gc_thresh,
	.maxlen = sizeof(int),
	.mode = 0644,
	.proc_handler = proc_dointvec,
	},
	};

	static int __net_init xfrm6_net_sysctl_init(struct net *net)
	{
	struct ctl_table *table;
	struct ctl_table_header *hdr;

	table = xfrm6_policy_table;
	if (!net_eq(net, &init_net)) {
	table = kmemdup(table, sizeof(xfrm6_policy_table), GFP_KERNEL);
	if (!table)
	goto err_alloc;

	table[0].data = &net->xfrm.xfrm6_dst_ops.gc_thresh;
	}

	hdr = register_net_sysctl_sz(net, "net/ipv6", table,
	ARRAY_SIZE(xfrm6_policy_table));
	if (!hdr)
	goto err_reg;

	net->ipv6.sysctl.xfrm6_hdr = hdr;
	return 0;

	err_reg:
	if (!net_eq(net, &init_net))
	kfree(table);
	err_alloc:
	return -ENOMEM;
	}

	static void __net_exit xfrm6_net_sysctl_exit(struct net *net)
	{
	const struct ctl_table *table;

	if (!net->ipv6.sysctl.xfrm6_hdr)
	return;

	table = net->ipv6.sysctl.xfrm6_hdr->ctl_table_arg;
	unregister_net_sysctl_table(net->ipv6.sysctl.xfrm6_hdr);
	if (!net_eq(net, &init_net))
	kfree(table);
	}
	#else /* CONFIG_SYSCTL */
	static inline int xfrm6_net_sysctl_init(struct net *net)
	{
	return 0;
	}

	static inline void xfrm6_net_sysctl_exit(struct net *net)
	{
	}
	#endif

	static int __net_init xfrm6_net_init(struct net *net)
	{
	int ret;

	memcpy(&net->xfrm.xfrm6_dst_ops, &xfrm6_dst_ops_template,
	sizeof(xfrm6_dst_ops_template));
	ret = dst_entries_init(&net->xfrm.xfrm6_dst_ops);
	if (ret)
	return ret;

	ret = xfrm6_net_sysctl_init(net);
	if (ret)
	dst_entries_destroy(&net->xfrm.xfrm6_dst_ops);

	return ret;
	}

	static void __net_exit xfrm6_net_exit(struct net *net)
	{
	xfrm6_net_sysctl_exit(net);
	dst_entries_destroy(&net->xfrm.xfrm6_dst_ops);
	}

	static struct pernet_operations xfrm6_net_ops = {
	.init = xfrm6_net_init,
	.exit = xfrm6_net_exit,
	};

	int __init xfrm6_init(void)
	{
	int ret;

	ret = xfrm6_policy_init();
	if (ret)
	goto out;
	ret = xfrm6_state_init();
	if (ret)
	goto out_policy;

	ret = xfrm6_protocol_init();
	if (ret)
	goto out_state;

	ret = register_pernet_subsys(&xfrm6_net_ops);
	if (ret)
	goto out_protocol;

	ret = xfrm_nat_keepalive_init(AF_INET6);
	if (ret)
	goto out_nat_keepalive;
	out:
	return ret;
	out_nat_keepalive:
	unregister_pernet_subsys(&xfrm6_net_ops);
	out_protocol:
	xfrm6_protocol_fini();
	out_state:
	xfrm6_state_fini();
	out_policy:
	xfrm6_policy_fini();
	goto out;
	}

	void xfrm6_fini(void)
	{
	xfrm_nat_keepalive_fini(AF_INET6);
	unregister_pernet_subsys(&xfrm6_net_ops);
	xfrm6_protocol_fini();
	xfrm6_policy_fini();
	xfrm6_state_fini();
	}