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/*
* net/ipv6/fib6_rules.c IPv6 Routing Policy Rules
*
* Copyright (C)2003-2006 Helsinki University of Technology
* Copyright (C)2003-2006 USAGI/WIDE Project
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2.
*
* Authors
* Thomas Graf <tgraf@suug.ch>
* Ville Nuorvala <vnuorval@tcs.hut.fi>
*/
#include <linux/netdevice.h>
#include <net/fib_rules.h>
#include <net/ipv6.h>
#include <net/addrconf.h>
#include <net/ip6_route.h>
#include <net/netlink.h>
struct fib6_rule
{
struct fib_rule common;
struct rt6key src;
struct rt6key dst;
u8 tclass;
};
static struct fib_rules_ops fib6_rules_ops;
static struct fib6_rule main_rule = {
.common = {
.refcnt = ATOMIC_INIT(2),
.pref = 0x7FFE,
.action = FR_ACT_TO_TBL,
.table = RT6_TABLE_MAIN,
},
};
static struct fib6_rule local_rule = {
.common = {
.refcnt = ATOMIC_INIT(2),
.pref = 0,
.action = FR_ACT_TO_TBL,
.table = RT6_TABLE_LOCAL,
.flags = FIB_RULE_PERMANENT,
},
};
struct dst_entry *fib6_rule_lookup(struct flowi *fl, int flags,
pol_lookup_t lookup)
{
struct fib_lookup_arg arg = {
.lookup_ptr = lookup,
};
fib_rules_lookup(&fib6_rules_ops, fl, flags, &arg);
if (arg.rule)
fib_rule_put(arg.rule);
if (arg.result)
return arg.result;
dst_hold(&ip6_null_entry.u.dst);
return &ip6_null_entry.u.dst;
}
static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
int flags, struct fib_lookup_arg *arg)
{
struct rt6_info *rt = NULL;
struct fib6_table *table;
pol_lookup_t lookup = arg->lookup_ptr;
switch (rule->action) {
case FR_ACT_TO_TBL:
break;
case FR_ACT_UNREACHABLE:
rt = &ip6_null_entry;
goto discard_pkt;
default:
case FR_ACT_BLACKHOLE:
rt = &ip6_blk_hole_entry;
goto discard_pkt;
case FR_ACT_PROHIBIT:
rt = &ip6_prohibit_entry;
goto discard_pkt;
}
table = fib6_get_table(rule->table);
if (table)
rt = lookup(table, flp, flags);
if (rt != &ip6_null_entry) {
struct fib6_rule *r = (struct fib6_rule *)rule;
/*
* If we need to find a source address for this traffic,
* we check the result if it meets requirement of the rule.
*/
if ((rule->flags & FIB_RULE_FIND_SADDR) &&
r->src.plen && !(flags & RT6_LOOKUP_F_HAS_SADDR)) {
struct in6_addr saddr;
if (ipv6_get_saddr(&rt->u.dst, &flp->fl6_dst,
&saddr))
goto again;
if (!ipv6_prefix_equal(&saddr, &r->src.addr,
r->src.plen))
goto again;
ipv6_addr_copy(&flp->fl6_src, &saddr);
}
goto out;
}
again:
dst_release(&rt->u.dst);
rt = NULL;
goto out;
discard_pkt:
dst_hold(&rt->u.dst);
out:
arg->result = rt;
return rt == NULL ? -EAGAIN : 0;
}
static int fib6_rule_match(struct fib_rule *rule, struct flowi *fl, int flags)
{
struct fib6_rule *r = (struct fib6_rule *) rule;
if (r->dst.plen &&
!ipv6_prefix_equal(&fl->fl6_dst, &r->dst.addr, r->dst.plen))
return 0;
/*
* If FIB_RULE_FIND_SADDR is set and we do not have a
* source address for the traffic, we defer check for
* source address.
*/
if (r->src.plen) {
if (flags & RT6_LOOKUP_F_HAS_SADDR) {
if (!ipv6_prefix_equal(&fl->fl6_src, &r->src.addr,
r->src.plen))
return 0;
} else if (!(r->common.flags & FIB_RULE_FIND_SADDR))
return 0;
}
if (r->tclass && r->tclass != ((ntohl(fl->fl6_flowlabel) >> 20) & 0xff))
return 0;
return 1;
}
static const struct nla_policy fib6_rule_policy[FRA_MAX+1] = {
FRA_GENERIC_POLICY,
};
static int fib6_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
struct nlmsghdr *nlh, struct fib_rule_hdr *frh,
struct nlattr **tb)
{
int err = -EINVAL;
struct fib6_rule *rule6 = (struct fib6_rule *) rule;
if (rule->action == FR_ACT_TO_TBL) {
if (rule->table == RT6_TABLE_UNSPEC)
goto errout;
if (fib6_new_table(rule->table) == NULL) {
err = -ENOBUFS;
goto errout;
}
}
if (frh->src_len)
nla_memcpy(&rule6->src.addr, tb[FRA_SRC],
sizeof(struct in6_addr));
if (frh->dst_len)
nla_memcpy(&rule6->dst.addr, tb[FRA_DST],
sizeof(struct in6_addr));
rule6->src.plen = frh->src_len;
rule6->dst.plen = frh->dst_len;
rule6->tclass = frh->tos;
err = 0;
errout:
return err;
}
static int fib6_rule_compare(struct fib_rule *rule, struct fib_rule_hdr *frh,
struct nlattr **tb)
{
struct fib6_rule *rule6 = (struct fib6_rule *) rule;
if (frh->src_len && (rule6->src.plen != frh->src_len))
return 0;
if (frh->dst_len && (rule6->dst.plen != frh->dst_len))
return 0;
if (frh->tos && (rule6->tclass != frh->tos))
return 0;
if (frh->src_len &&
nla_memcmp(tb[FRA_SRC], &rule6->src.addr, sizeof(struct in6_addr)))
return 0;
if (frh->dst_len &&
nla_memcmp(tb[FRA_DST], &rule6->dst.addr, sizeof(struct in6_addr)))
return 0;
return 1;
}
static int fib6_rule_fill(struct fib_rule *rule, struct sk_buff *skb,
struct nlmsghdr *nlh, struct fib_rule_hdr *frh)
{
struct fib6_rule *rule6 = (struct fib6_rule *) rule;
frh->family = AF_INET6;
frh->dst_len = rule6->dst.plen;
frh->src_len = rule6->src.plen;
frh->tos = rule6->tclass;
if (rule6->dst.plen)
NLA_PUT(skb, FRA_DST, sizeof(struct in6_addr),
&rule6->dst.addr);
if (rule6->src.plen)
NLA_PUT(skb, FRA_SRC, sizeof(struct in6_addr),
&rule6->src.addr);
return 0;
nla_put_failure:
return -ENOBUFS;
}
static u32 fib6_rule_default_pref(void)
{
return 0x3FFF;
}
static size_t fib6_rule_nlmsg_payload(struct fib_rule *rule)
{
return nla_total_size(16) /* dst */
+ nla_total_size(16); /* src */
}
static struct fib_rules_ops fib6_rules_ops = {
.family = AF_INET6,
.rule_size = sizeof(struct fib6_rule),
.addr_size = sizeof(struct in6_addr),
.action = fib6_rule_action,
.match = fib6_rule_match,
.configure = fib6_rule_configure,
.compare = fib6_rule_compare,
.fill = fib6_rule_fill,
.default_pref = fib6_rule_default_pref,
.nlmsg_payload = fib6_rule_nlmsg_payload,
.nlgroup = RTNLGRP_IPV6_RULE,
.policy = fib6_rule_policy,
.rules_list = LIST_HEAD_INIT(fib6_rules_ops.rules_list),
.owner = THIS_MODULE,
};
void __init fib6_rules_init(void)
{
list_add_tail(&local_rule.common.list, &fib6_rules_ops.rules_list);
list_add_tail(&main_rule.common.list, &fib6_rules_ops.rules_list);
fib_rules_register(&fib6_rules_ops);
}
void fib6_rules_cleanup(void)
{
fib_rules_unregister(&fib6_rules_ops);
}
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