From 92d8682926342d2b6aa5b2ecc02221e00e1573a0 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Fri, 4 Feb 2011 15:55:25 -0800 Subject: inetpeer: Move ICMP rate limiting state into inet_peer entries. Like metrics, the ICMP rate limiting bits are cached state about a destination. So move it into the inet_peer entries. If an inet_peer cannot be bound (the reason is memory allocation failure or similar), the policy is to allow. Signed-off-by: David S. Miller --- net/ipv4/icmp.c | 49 ++++++++----------------------------------------- 1 file changed, 8 insertions(+), 41 deletions(-) (limited to 'net/ipv4/icmp.c') diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 4aa1b7f01ea0..ad2bcf1b69ae 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; } -- cgit v1.2.3-70-g09d2