OpenWrt – Rev 1
?pathlinks?
From: Jonas Gorski <jogo@openwrt.org>
Subject: ipv6: allow rejecting with "source address failed policy"
RFC6204 L-14 requires rejecting traffic from invalid addresses with
ICMPv6 Destination Unreachable, Code 5 (Source address failed ingress/
egress policy) on the LAN side, so add an appropriate rule for that.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
---
include/net/netns/ipv6.h | 1 +
include/uapi/linux/fib_rules.h | 4 +++
include/uapi/linux/rtnetlink.h | 1 +
net/ipv4/fib_semantics.c | 4 +++
net/ipv4/fib_trie.c | 1 +
net/ipv4/ipmr.c | 1 +
net/ipv6/fib6_rules.c | 4 +++
net/ipv6/ip6mr.c | 2 ++
net/ipv6/route.c | 58 +++++++++++++++++++++++++++++++++++++++++-
9 files changed, 75 insertions(+), 1 deletion(-)
--- a/include/net/netns/ipv6.h
+++ b/include/net/netns/ipv6.h
@@ -66,6 +66,7 @@ struct netns_ipv6 {
unsigned long ip6_rt_last_gc;
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
struct rt6_info *ip6_prohibit_entry;
+ struct rt6_info *ip6_policy_failed_entry;
struct rt6_info *ip6_blk_hole_entry;
struct fib6_table *fib6_local_tbl;
struct fib_rules_ops *fib6_rules_ops;
--- a/include/uapi/linux/fib_rules.h
+++ b/include/uapi/linux/fib_rules.h
@@ -66,6 +66,10 @@ enum {
FR_ACT_BLACKHOLE, /* Drop without notification */
FR_ACT_UNREACHABLE, /* Drop with ENETUNREACH */
FR_ACT_PROHIBIT, /* Drop with EACCES */
+ FR_ACT_RES9,
+ FR_ACT_RES10,
+ FR_ACT_RES11,
+ FR_ACT_POLICY_FAILED, /* Drop with EACCES */
__FR_ACT_MAX,
};
--- a/include/uapi/linux/rtnetlink.h
+++ b/include/uapi/linux/rtnetlink.h
@@ -215,6 +215,7 @@ enum {
RTN_THROW, /* Not in this table */
RTN_NAT, /* Translate this address */
RTN_XRESOLVE, /* Use external resolver */
+ RTN_POLICY_FAILED, /* Failed ingress/egress policy */
__RTN_MAX
};
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -138,6 +138,10 @@ const struct fib_prop fib_props[RTN_MAX
.error = -EINVAL,
.scope = RT_SCOPE_NOWHERE,
},
+ [RTN_POLICY_FAILED] = {
+ .error = -EACCES,
+ .scope = RT_SCOPE_UNIVERSE,
+ },
};
static void rt_fibinfo_free(struct rtable __rcu **rtp)
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -2406,6 +2406,7 @@ static const char *const rtn_type_names[
[RTN_THROW] = "THROW",
[RTN_NAT] = "NAT",
[RTN_XRESOLVE] = "XRESOLVE",
+ [RTN_POLICY_FAILED] = "POLICY_FAILED",
};
static inline const char *rtn_type(char *buf, size_t len, unsigned int t)
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -159,6 +159,7 @@ static int ipmr_rule_action(struct fib_r
case FR_ACT_UNREACHABLE:
return -ENETUNREACH;
case FR_ACT_PROHIBIT:
+ case FR_ACT_POLICY_FAILED:
return -EACCES;
case FR_ACT_BLACKHOLE:
default:
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -77,6 +77,10 @@ static int fib6_rule_action(struct fib_r
err = -EACCES;
rt = net->ipv6.ip6_prohibit_entry;
goto discard_pkt;
+ case FR_ACT_POLICY_FAILED:
+ err = -EACCES;
+ rt = net->ipv6.ip6_policy_failed_entry;
+ goto discard_pkt;
}
tb_id = fib_rule_get_table(rule, arg);
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -169,6 +169,8 @@ static int ip6mr_rule_action(struct fib_
return -ENETUNREACH;
case FR_ACT_PROHIBIT:
return -EACCES;
+ case FR_ACT_POLICY_FAILED:
+ return -EACCES;
case FR_ACT_BLACKHOLE:
default:
return -EINVAL;
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -91,6 +91,8 @@ static int ip6_pkt_discard(struct sk_bu
static int ip6_pkt_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
static int ip6_pkt_prohibit(struct sk_buff *skb);
static int ip6_pkt_prohibit_out(struct net *net, struct sock *sk, struct sk_buff *skb);
+static int ip6_pkt_policy_failed(struct sk_buff *skb);
+static int ip6_pkt_policy_failed_out(struct net *net, struct sock *sk, struct sk_buff *skb);
static void ip6_link_failure(struct sk_buff *skb);
static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
struct sk_buff *skb, u32 mtu);
@@ -300,6 +302,21 @@ static const struct rt6_info ip6_prohibi
.rt6i_ref = ATOMIC_INIT(1),
};
+static const struct rt6_info ip6_policy_failed_entry_template = {
+ .dst = {
+ .__refcnt = ATOMIC_INIT(1),
+ .__use = 1,
+ .obsolete = DST_OBSOLETE_FORCE_CHK,
+ .error = -EACCES,
+ .input = ip6_pkt_policy_failed,
+ .output = ip6_pkt_policy_failed_out,
+ },
+ .rt6i_flags = (RTF_REJECT | RTF_NONEXTHOP),
+ .rt6i_protocol = RTPROT_KERNEL,
+ .rt6i_metric = ~(u32) 0,
+ .rt6i_ref = ATOMIC_INIT(1),
+};
+
static const struct rt6_info ip6_blk_hole_entry_template = {
.dst = {
.__refcnt = ATOMIC_INIT(1),
@@ -1970,6 +1987,11 @@ static struct rt6_info *ip6_route_info_c
rt->dst.output = ip6_pkt_prohibit_out;
rt->dst.input = ip6_pkt_prohibit;
break;
+ case RTN_POLICY_FAILED:
+ rt->dst.error = -EACCES;
+ rt->dst.output = ip6_pkt_policy_failed_out;
+ rt->dst.input = ip6_pkt_policy_failed;
+ break;
case RTN_THROW:
case RTN_UNREACHABLE:
default:
@@ -2613,6 +2635,17 @@ static int ip6_pkt_prohibit_out(struct n
return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
}
+static int ip6_pkt_policy_failed(struct sk_buff *skb)
+{
+ return ip6_pkt_drop(skb, ICMPV6_POLICY_FAIL, IPSTATS_MIB_INNOROUTES);
+}
+
+static int ip6_pkt_policy_failed_out(struct net *net, struct sock *sk, struct sk_buff *skb)
+{
+ skb->dev = skb_dst(skb)->dev;
+ return ip6_pkt_drop(skb, ICMPV6_POLICY_FAIL, IPSTATS_MIB_OUTNOROUTES);
+}
+
/*
* Allocate a dst for local (unicast / anycast) address.
*/
@@ -2850,7 +2883,8 @@ static int rtm_to_fib6_config(struct sk_
if (rtm->rtm_type == RTN_UNREACHABLE ||
rtm->rtm_type == RTN_BLACKHOLE ||
rtm->rtm_type == RTN_PROHIBIT ||
- rtm->rtm_type == RTN_THROW)
+ rtm->rtm_type == RTN_THROW ||
+ rtm->rtm_type == RTN_POLICY_FAILED)
cfg->fc_flags |= RTF_REJECT;
if (rtm->rtm_type == RTN_LOCAL)
@@ -3222,6 +3256,9 @@ static int rt6_fill_node(struct net *net
case -EACCES:
rtm->rtm_type = RTN_PROHIBIT;
break;
+ case -EPERM:
+ rtm->rtm_type = RTN_POLICY_FAILED;
+ break;
case -EAGAIN:
rtm->rtm_type = RTN_THROW;
break;
@@ -3498,6 +3535,8 @@ static int ip6_route_dev_notify(struct n
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
net->ipv6.ip6_prohibit_entry->dst.dev = dev;
net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
+ net->ipv6.ip6_policy_failed_entry->dst.dev = dev;
+ net->ipv6.ip6_policy_failed_entry->rt6i_idev = in6_dev_get(dev);
net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
#endif
@@ -3509,6 +3548,7 @@ static int ip6_route_dev_notify(struct n
in6_dev_put(net->ipv6.ip6_null_entry->rt6i_idev);
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
in6_dev_put(net->ipv6.ip6_prohibit_entry->rt6i_idev);
+ in6_dev_put(net->ipv6.ip6_policy_failed_entry->rt6i_idev);
in6_dev_put(net->ipv6.ip6_blk_hole_entry->rt6i_idev);
#endif
}
@@ -3724,6 +3764,17 @@ static int __net_init ip6_route_net_init
net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
ip6_template_metrics, true);
+
+ net->ipv6.ip6_policy_failed_entry =
+ kmemdup(&ip6_policy_failed_entry_template,
+ sizeof(*net->ipv6.ip6_policy_failed_entry), GFP_KERNEL);
+ if (!net->ipv6.ip6_policy_failed_entry)
+ goto out_ip6_blk_hole_entry;
+ net->ipv6.ip6_policy_failed_entry->dst.path =
+ (struct dst_entry *)net->ipv6.ip6_policy_failed_entry;
+ net->ipv6.ip6_policy_failed_entry->dst.ops = &net->ipv6.ip6_dst_ops;
+ dst_init_metrics(&net->ipv6.ip6_policy_failed_entry->dst,
+ ip6_template_metrics, true);
#endif
net->ipv6.sysctl.flush_delay = 0;
@@ -3742,6 +3793,8 @@ out:
return ret;
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
+out_ip6_blk_hole_entry:
+ kfree(net->ipv6.ip6_blk_hole_entry);
out_ip6_prohibit_entry:
kfree(net->ipv6.ip6_prohibit_entry);
out_ip6_null_entry:
@@ -3759,6 +3812,7 @@ static void __net_exit ip6_route_net_exi
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
kfree(net->ipv6.ip6_prohibit_entry);
kfree(net->ipv6.ip6_blk_hole_entry);
+ kfree(net->ipv6.ip6_policy_failed_entry);
#endif
dst_entries_destroy(&net->ipv6.ip6_dst_ops);
}
@@ -3832,6 +3886,9 @@ void __init ip6_route_init_special_entri
init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
+ init_net.ipv6.ip6_policy_failed_entry->dst.dev = init_net.loopback_dev;
+ init_net.ipv6.ip6_policy_failed_entry->rt6i_idev =
+ in6_dev_get(init_net.loopback_dev);
#endif
}