diff options
Diffstat (limited to 'net/ipv4/xfrm4_policy.c')
| -rw-r--r-- | net/ipv4/xfrm4_policy.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c new file mode 100644 index 000000000..3d0dfa6cf --- /dev/null +++ b/net/ipv4/xfrm4_policy.c @@ -0,0 +1,259 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * xfrm4_policy.c + * + * Changes: + * Kazunori MIYAZAWA @USAGI + * YOSHIFUJI Hideaki @USAGI + * Split up af-specific portion + * + */ + +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/inetdevice.h> +#include <net/dst.h> +#include <net/xfrm.h> +#include <net/ip.h> +#include <net/l3mdev.h> + +static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4, + int tos, int oif, + const xfrm_address_t *saddr, + const xfrm_address_t *daddr, + u32 mark) +{ + struct rtable *rt; + + memset(fl4, 0, sizeof(*fl4)); + fl4->daddr = daddr->a4; + fl4->flowi4_tos = tos; + fl4->flowi4_l3mdev = l3mdev_master_ifindex_by_index(net, oif); + fl4->flowi4_mark = mark; + if (saddr) + fl4->saddr = saddr->a4; + + rt = __ip_route_output_key(net, fl4); + if (!IS_ERR(rt)) + return &rt->dst; + + return ERR_CAST(rt); +} + +static struct dst_entry *xfrm4_dst_lookup(struct net *net, int tos, int oif, + const xfrm_address_t *saddr, + const xfrm_address_t *daddr, + u32 mark) +{ + struct flowi4 fl4; + + return __xfrm4_dst_lookup(net, &fl4, tos, oif, saddr, daddr, mark); +} + +static int xfrm4_get_saddr(struct net *net, int oif, + xfrm_address_t *saddr, xfrm_address_t *daddr, + u32 mark) +{ + struct dst_entry *dst; + struct flowi4 fl4; + + dst = __xfrm4_dst_lookup(net, &fl4, 0, oif, NULL, daddr, mark); + if (IS_ERR(dst)) + return -EHOSTUNREACH; + + saddr->a4 = fl4.saddr; + dst_release(dst); + return 0; +} + +static int xfrm4_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, + const struct flowi *fl) +{ + struct rtable *rt = (struct rtable *)xdst->route; + const struct flowi4 *fl4 = &fl->u.ip4; + + xdst->u.rt.rt_iif = fl4->flowi4_iif; + + xdst->u.dst.dev = dev; + netdev_hold(dev, &xdst->u.dst.dev_tracker, GFP_ATOMIC); + + /* Sheit... I remember I did this right. Apparently, + * it was magically lost, so this code needs audit */ + xdst->u.rt.rt_is_input = rt->rt_is_input; + xdst->u.rt.rt_flags = rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | + RTCF_LOCAL); + xdst->u.rt.rt_type = rt->rt_type; + xdst->u.rt.rt_uses_gateway = rt->rt_uses_gateway; + xdst->u.rt.rt_gw_family = rt->rt_gw_family; + if (rt->rt_gw_family == AF_INET) + xdst->u.rt.rt_gw4 = rt->rt_gw4; + else if (rt->rt_gw_family == AF_INET6) + xdst->u.rt.rt_gw6 = rt->rt_gw6; + xdst->u.rt.rt_pmtu = rt->rt_pmtu; + xdst->u.rt.rt_mtu_locked = rt->rt_mtu_locked; + INIT_LIST_HEAD(&xdst->u.rt.rt_uncached); + rt_add_uncached_list(&xdst->u.rt); + + return 0; +} + +static void xfrm4_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 xfrm4_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 xfrm4_dst_destroy(struct dst_entry *dst) +{ + struct xfrm_dst *xdst = (struct xfrm_dst *)dst; + + dst_destroy_metrics_generic(dst); + if (xdst->u.rt.rt_uncached_list) + rt_del_uncached_list(&xdst->u.rt); + xfrm_dst_destroy(xdst); +} + +static void xfrm4_dst_ifdown(struct dst_entry *dst, struct net_device *dev, + int unregister) +{ + if (!unregister) + return; + + xfrm_dst_ifdown(dst, dev); +} + +static struct dst_ops xfrm4_dst_ops_template = { + .family = AF_INET, + .update_pmtu = xfrm4_update_pmtu, + .redirect = xfrm4_redirect, + .cow_metrics = dst_cow_metrics_generic, + .destroy = xfrm4_dst_destroy, + .ifdown = xfrm4_dst_ifdown, + .local_out = __ip_local_out, + .gc_thresh = 32768, +}; + +static const struct xfrm_policy_afinfo xfrm4_policy_afinfo = { + .dst_ops = &xfrm4_dst_ops_template, + .dst_lookup = xfrm4_dst_lookup, + .get_saddr = xfrm4_get_saddr, + .fill_dst = xfrm4_fill_dst, + .blackhole_route = ipv4_blackhole_route, +}; + +#ifdef CONFIG_SYSCTL +static struct ctl_table xfrm4_policy_table[] = { + { + .procname = "xfrm4_gc_thresh", + .data = &init_net.xfrm.xfrm4_dst_ops.gc_thresh, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { } +}; + +static __net_init int xfrm4_net_sysctl_init(struct net *net) +{ + struct ctl_table *table; + struct ctl_table_header *hdr; + + table = xfrm4_policy_table; + if (!net_eq(net, &init_net)) { + table = kmemdup(table, sizeof(xfrm4_policy_table), GFP_KERNEL); + if (!table) + goto err_alloc; + + table[0].data = &net->xfrm.xfrm4_dst_ops.gc_thresh; + } + + hdr = register_net_sysctl(net, "net/ipv4", table); + if (!hdr) + goto err_reg; + + net->ipv4.xfrm4_hdr = hdr; + return 0; + +err_reg: + if (!net_eq(net, &init_net)) + kfree(table); +err_alloc: + return -ENOMEM; +} + +static __net_exit void xfrm4_net_sysctl_exit(struct net *net) +{ + struct ctl_table *table; + + if (!net->ipv4.xfrm4_hdr) + return; + + table = net->ipv4.xfrm4_hdr->ctl_table_arg; + unregister_net_sysctl_table(net->ipv4.xfrm4_hdr); + if (!net_eq(net, &init_net)) + kfree(table); +} +#else /* CONFIG_SYSCTL */ +static inline int xfrm4_net_sysctl_init(struct net *net) +{ + return 0; +} + +static inline void xfrm4_net_sysctl_exit(struct net *net) +{ +} +#endif + +static int __net_init xfrm4_net_init(struct net *net) +{ + int ret; + + memcpy(&net->xfrm.xfrm4_dst_ops, &xfrm4_dst_ops_template, + sizeof(xfrm4_dst_ops_template)); + ret = dst_entries_init(&net->xfrm.xfrm4_dst_ops); + if (ret) + return ret; + + ret = xfrm4_net_sysctl_init(net); + if (ret) + dst_entries_destroy(&net->xfrm.xfrm4_dst_ops); + + return ret; +} + +static void __net_exit xfrm4_net_exit(struct net *net) +{ + xfrm4_net_sysctl_exit(net); + dst_entries_destroy(&net->xfrm.xfrm4_dst_ops); +} + +static struct pernet_operations __net_initdata xfrm4_net_ops = { + .init = xfrm4_net_init, + .exit = xfrm4_net_exit, +}; + +static void __init xfrm4_policy_init(void) +{ + xfrm_policy_register_afinfo(&xfrm4_policy_afinfo, AF_INET); +} + +void __init xfrm4_init(void) +{ + xfrm4_state_init(); + xfrm4_policy_init(); + xfrm4_protocol_init(); + register_pernet_subsys(&xfrm4_net_ops); +} |