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Diffstat (limited to 'net/ipv4/icmp.c')
-rw-r--r--net/ipv4/icmp.c240
1 files changed, 113 insertions, 127 deletions
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 4aa1b7f01ea0..a91dc1611081 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -233,48 +233,11 @@ static inline void icmp_xmit_unlock(struct sock *sk)
* Send an ICMP frame.
*/
-/*
- * Check transmit rate limitation for given message.
- * The rate information is held in the destination cache now.
- * This function is generic and could be used for other purposes
- * too. It uses a Token bucket filter as suggested by Alexey Kuznetsov.
- *
- * Note that the same dst_entry fields are modified by functions in
- * route.c too, but these work for packet destinations while xrlim_allow
- * works for icmp destinations. This means the rate limiting information
- * for one "ip object" is shared - and these ICMPs are twice limited:
- * by source and by destination.
- *
- * RFC 1812: 4.3.2.8 SHOULD be able to limit error message rate
- * SHOULD allow setting of rate limits
- *
- * Shared between ICMPv4 and ICMPv6.
- */
-#define XRLIM_BURST_FACTOR 6
-int xrlim_allow(struct dst_entry *dst, int timeout)
-{
- unsigned long now, token = dst->rate_tokens;
- int rc = 0;
-
- now = jiffies;
- token += now - dst->rate_last;
- dst->rate_last = now;
- if (token > XRLIM_BURST_FACTOR * timeout)
- token = XRLIM_BURST_FACTOR * timeout;
- if (token >= timeout) {
- token -= timeout;
- rc = 1;
- }
- dst->rate_tokens = token;
- return rc;
-}
-EXPORT_SYMBOL(xrlim_allow);
-
-static inline int icmpv4_xrlim_allow(struct net *net, struct rtable *rt,
+static inline bool icmpv4_xrlim_allow(struct net *net, struct rtable *rt,
int type, int code)
{
struct dst_entry *dst = &rt->dst;
- int rc = 1;
+ bool rc = true;
if (type > NR_ICMP_TYPES)
goto out;
@@ -288,8 +251,12 @@ static inline int icmpv4_xrlim_allow(struct net *net, struct rtable *rt,
goto out;
/* Limit if icmp type is enabled in ratemask. */
- if ((1 << type) & net->ipv4.sysctl_icmp_ratemask)
- rc = xrlim_allow(dst, net->ipv4.sysctl_icmp_ratelimit);
+ if ((1 << type) & net->ipv4.sysctl_icmp_ratemask) {
+ if (!rt->peer)
+ rt_bind_peer(rt, 1);
+ rc = inet_peer_xrlim_allow(rt->peer,
+ net->ipv4.sysctl_icmp_ratelimit);
+ }
out:
return rc;
}
@@ -386,12 +353,15 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
daddr = icmp_param->replyopts.faddr;
}
{
- struct flowi fl = { .fl4_dst= daddr,
- .fl4_src = rt->rt_spec_dst,
- .fl4_tos = RT_TOS(ip_hdr(skb)->tos),
- .proto = IPPROTO_ICMP };
- security_skb_classify_flow(skb, &fl);
- if (ip_route_output_key(net, &rt, &fl))
+ struct flowi4 fl4 = {
+ .daddr = daddr,
+ .saddr = rt->rt_spec_dst,
+ .flowi4_tos = RT_TOS(ip_hdr(skb)->tos),
+ .flowi4_proto = IPPROTO_ICMP,
+ };
+ security_skb_classify_flow(skb, flowi4_to_flowi(&fl4));
+ rt = ip_route_output_key(net, &fl4);
+ if (IS_ERR(rt))
goto out_unlock;
}
if (icmpv4_xrlim_allow(net, rt, icmp_param->data.icmph.type,
@@ -402,6 +372,97 @@ out_unlock:
icmp_xmit_unlock(sk);
}
+static struct rtable *icmp_route_lookup(struct net *net, struct sk_buff *skb_in,
+ struct iphdr *iph,
+ __be32 saddr, u8 tos,
+ int type, int code,
+ struct icmp_bxm *param)
+{
+ struct flowi4 fl4 = {
+ .daddr = (param->replyopts.srr ?
+ param->replyopts.faddr : iph->saddr),
+ .saddr = saddr,
+ .flowi4_tos = RT_TOS(tos),
+ .flowi4_proto = IPPROTO_ICMP,
+ .fl4_icmp_type = type,
+ .fl4_icmp_code = code,
+ };
+ struct rtable *rt, *rt2;
+ int err;
+
+ security_skb_classify_flow(skb_in, flowi4_to_flowi(&fl4));
+ rt = __ip_route_output_key(net, &fl4);
+ if (IS_ERR(rt))
+ return rt;
+
+ /* No need to clone since we're just using its address. */
+ rt2 = rt;
+
+ if (!fl4.saddr)
+ fl4.saddr = rt->rt_src;
+
+ rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
+ flowi4_to_flowi(&fl4), NULL, 0);
+ if (!IS_ERR(rt)) {
+ if (rt != rt2)
+ return rt;
+ } else if (PTR_ERR(rt) == -EPERM) {
+ rt = NULL;
+ } else
+ return rt;
+
+ err = xfrm_decode_session_reverse(skb_in, flowi4_to_flowi(&fl4), AF_INET);
+ if (err)
+ goto relookup_failed;
+
+ if (inet_addr_type(net, fl4.saddr) == RTN_LOCAL) {
+ rt2 = __ip_route_output_key(net, &fl4);
+ if (IS_ERR(rt2))
+ err = PTR_ERR(rt2);
+ } else {
+ struct flowi4 fl4_2 = {};
+ unsigned long orefdst;
+
+ fl4_2.daddr = fl4.saddr;
+ rt2 = ip_route_output_key(net, &fl4_2);
+ if (IS_ERR(rt2)) {
+ err = PTR_ERR(rt2);
+ goto relookup_failed;
+ }
+ /* Ugh! */
+ orefdst = skb_in->_skb_refdst; /* save old refdst */
+ err = ip_route_input(skb_in, fl4.daddr, fl4.saddr,
+ RT_TOS(tos), rt2->dst.dev);
+
+ dst_release(&rt2->dst);
+ rt2 = skb_rtable(skb_in);
+ skb_in->_skb_refdst = orefdst; /* restore old refdst */
+ }
+
+ if (err)
+ goto relookup_failed;
+
+ rt2 = (struct rtable *) xfrm_lookup(net, &rt2->dst,
+ flowi4_to_flowi(&fl4), NULL,
+ XFRM_LOOKUP_ICMP);
+ if (!IS_ERR(rt2)) {
+ dst_release(&rt->dst);
+ rt = rt2;
+ } else if (PTR_ERR(rt2) == -EPERM) {
+ if (rt)
+ dst_release(&rt->dst);
+ return rt2;
+ } else {
+ err = PTR_ERR(rt2);
+ goto relookup_failed;
+ }
+ return rt;
+
+relookup_failed:
+ if (rt)
+ return rt;
+ return ERR_PTR(err);
+}
/*
* Send an ICMP message in response to a situation
@@ -507,7 +568,7 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
rcu_read_lock();
if (rt_is_input_route(rt) &&
net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr)
- dev = dev_get_by_index_rcu(net, rt->fl.iif);
+ dev = dev_get_by_index_rcu(net, rt->rt_iif);
if (dev)
saddr = inet_select_addr(dev, 0, RT_SCOPE_LINK);
@@ -539,86 +600,11 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)
ipc.opt = &icmp_param.replyopts;
ipc.tx_flags = 0;
- {
- struct flowi fl = {
- .fl4_dst = icmp_param.replyopts.srr ?
- icmp_param.replyopts.faddr : iph->saddr,
- .fl4_src = saddr,
- .fl4_tos = RT_TOS(tos),
- .proto = IPPROTO_ICMP,
- .fl_icmp_type = type,
- .fl_icmp_code = code,
- };
- int err;
- struct rtable *rt2;
-
- security_skb_classify_flow(skb_in, &fl);
- if (__ip_route_output_key(net, &rt, &fl))
- goto out_unlock;
-
- /* No need to clone since we're just using its address. */
- rt2 = rt;
-
- if (!fl.nl_u.ip4_u.saddr)
- fl.nl_u.ip4_u.saddr = rt->rt_src;
-
- err = xfrm_lookup(net, (struct dst_entry **)&rt, &fl, NULL, 0);
- switch (err) {
- case 0:
- if (rt != rt2)
- goto route_done;
- break;
- case -EPERM:
- rt = NULL;
- break;
- default:
- goto out_unlock;
- }
-
- if (xfrm_decode_session_reverse(skb_in, &fl, AF_INET))
- goto relookup_failed;
-
- if (inet_addr_type(net, fl.fl4_src) == RTN_LOCAL)
- err = __ip_route_output_key(net, &rt2, &fl);
- else {
- struct flowi fl2 = {};
- unsigned long orefdst;
-
- fl2.fl4_dst = fl.fl4_src;
- if (ip_route_output_key(net, &rt2, &fl2))
- goto relookup_failed;
-
- /* Ugh! */
- orefdst = skb_in->_skb_refdst; /* save old refdst */
- err = ip_route_input(skb_in, fl.fl4_dst, fl.fl4_src,
- RT_TOS(tos), rt2->dst.dev);
-
- dst_release(&rt2->dst);
- rt2 = skb_rtable(skb_in);
- skb_in->_skb_refdst = orefdst; /* restore old refdst */
- }
-
- if (err)
- goto relookup_failed;
-
- err = xfrm_lookup(net, (struct dst_entry **)&rt2, &fl, NULL,
- XFRM_LOOKUP_ICMP);
- switch (err) {
- case 0:
- dst_release(&rt->dst);
- rt = rt2;
- break;
- case -EPERM:
- goto ende;
- default:
-relookup_failed:
- if (!rt)
- goto out_unlock;
- break;
- }
- }
+ rt = icmp_route_lookup(net, skb_in, iph, saddr, tos,
+ type, code, &icmp_param);
+ if (IS_ERR(rt))
+ goto out_unlock;
-route_done:
if (!icmpv4_xrlim_allow(net, rt, type, code))
goto ende;