diff options
Diffstat (limited to 'net/ipv4/ip_input.c')
-rw-r--r-- | net/ipv4/ip_input.c | 141 |
1 files changed, 77 insertions, 64 deletions
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index c703528e0bcd..473d0f2b2e0d 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -150,7 +150,7 @@ * SNMP management statistics */ -DEFINE_SNMP_STAT(struct ipstats_mib, ip_statistics); +DEFINE_SNMP_STAT(struct ipstats_mib, ip_statistics) __read_mostly; /* * Process Router Attention IP option @@ -225,8 +225,8 @@ static inline int ip_local_deliver_finish(struct sk_buff *skb) /* If there maybe a raw socket we must check - if not we * don't care less */ - if (raw_sk) - raw_v4_input(skb, skb->nh.iph, hash); + if (raw_sk && !raw_v4_input(skb, skb->nh.iph, hash)) + raw_sk = NULL; if ((ipprot = rcu_dereference(inet_protos[hash])) != NULL) { int ret; @@ -279,18 +279,70 @@ int ip_local_deliver(struct sk_buff *skb) ip_local_deliver_finish); } -static inline int ip_rcv_finish(struct sk_buff *skb) +static inline int ip_rcv_options(struct sk_buff *skb) { + struct ip_options *opt; + struct iphdr *iph; struct net_device *dev = skb->dev; + + /* It looks as overkill, because not all + IP options require packet mangling. + But it is the easiest for now, especially taking + into account that combination of IP options + and running sniffer is extremely rare condition. + --ANK (980813) + */ + if (skb_cow(skb, skb_headroom(skb))) { + IP_INC_STATS_BH(IPSTATS_MIB_INDISCARDS); + goto drop; + } + + iph = skb->nh.iph; + + if (ip_options_compile(NULL, skb)) { + IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); + goto drop; + } + + opt = &(IPCB(skb)->opt); + if (unlikely(opt->srr)) { + struct in_device *in_dev = in_dev_get(dev); + if (in_dev) { + if (!IN_DEV_SOURCE_ROUTE(in_dev)) { + if (IN_DEV_LOG_MARTIANS(in_dev) && + net_ratelimit()) + printk(KERN_INFO "source route option " + "%u.%u.%u.%u -> %u.%u.%u.%u\n", + NIPQUAD(iph->saddr), + NIPQUAD(iph->daddr)); + in_dev_put(in_dev); + goto drop; + } + + in_dev_put(in_dev); + } + + if (ip_options_rcv_srr(skb)) + goto drop; + } + + return 0; +drop: + return -1; +} + +static inline int ip_rcv_finish(struct sk_buff *skb) +{ struct iphdr *iph = skb->nh.iph; - int err; /* * Initialise the virtual path cache for the packet. It describes * how the packet travels inside Linux networking. */ - if (skb->dst == NULL) { - if ((err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev))) { + if (likely(skb->dst == NULL)) { + int err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, + skb->dev); + if (unlikely(err)) { if (err == -EHOSTUNREACH) IP_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); goto drop; @@ -298,7 +350,7 @@ static inline int ip_rcv_finish(struct sk_buff *skb) } #ifdef CONFIG_NET_CLS_ROUTE - if (skb->dst->tclassid) { + if (unlikely(skb->dst->tclassid)) { struct ip_rt_acct *st = ip_rt_acct + 256*smp_processor_id(); u32 idx = skb->dst->tclassid; st[idx&0xFF].o_packets++; @@ -308,48 +360,11 @@ static inline int ip_rcv_finish(struct sk_buff *skb) } #endif - if (iph->ihl > 5) { - struct ip_options *opt; - - /* It looks as overkill, because not all - IP options require packet mangling. - But it is the easiest for now, especially taking - into account that combination of IP options - and running sniffer is extremely rare condition. - --ANK (980813) - */ - - if (skb_cow(skb, skb_headroom(skb))) { - IP_INC_STATS_BH(IPSTATS_MIB_INDISCARDS); - goto drop; - } - iph = skb->nh.iph; - - if (ip_options_compile(NULL, skb)) - goto inhdr_error; - - opt = &(IPCB(skb)->opt); - if (opt->srr) { - struct in_device *in_dev = in_dev_get(dev); - if (in_dev) { - if (!IN_DEV_SOURCE_ROUTE(in_dev)) { - if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) - printk(KERN_INFO "source route option %u.%u.%u.%u -> %u.%u.%u.%u\n", - NIPQUAD(iph->saddr), NIPQUAD(iph->daddr)); - in_dev_put(in_dev); - goto drop; - } - in_dev_put(in_dev); - } - if (ip_options_rcv_srr(skb)) - goto drop; - } - } + if (iph->ihl > 5 && ip_rcv_options(skb)) + goto drop; return dst_input(skb); -inhdr_error: - IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); drop: kfree_skb(skb); return NET_RX_DROP; @@ -358,9 +373,10 @@ drop: /* * Main IP Receive routine. */ -int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt) +int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { struct iphdr *iph; + u32 len; /* When the interface is in promisc. mode, drop all the crap * that it receives, do not try to analyse it. @@ -392,29 +408,27 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt) */ if (iph->ihl < 5 || iph->version != 4) - goto inhdr_error; + goto inhdr_error; if (!pskb_may_pull(skb, iph->ihl*4)) goto inhdr_error; iph = skb->nh.iph; - if (ip_fast_csum((u8 *)iph, iph->ihl) != 0) - goto inhdr_error; + if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) + goto inhdr_error; - { - __u32 len = ntohs(iph->tot_len); - if (skb->len < len || len < (iph->ihl<<2)) - goto inhdr_error; + len = ntohs(iph->tot_len); + if (skb->len < len || len < (iph->ihl*4)) + goto inhdr_error; - /* Our transport medium may have padded the buffer out. Now we know it - * is IP we can trim to the true length of the frame. - * Note this now means skb->len holds ntohs(iph->tot_len). - */ - if (pskb_trim_rcsum(skb, len)) { - IP_INC_STATS_BH(IPSTATS_MIB_INDISCARDS); - goto drop; - } + /* Our transport medium may have padded the buffer out. Now we know it + * is IP we can trim to the true length of the frame. + * Note this now means skb->len holds ntohs(iph->tot_len). + */ + if (pskb_trim_rcsum(skb, len)) { + IP_INC_STATS_BH(IPSTATS_MIB_INDISCARDS); + goto drop; } return NF_HOOK(PF_INET, NF_IP_PRE_ROUTING, skb, dev, NULL, @@ -428,5 +442,4 @@ out: return NET_RX_DROP; } -EXPORT_SYMBOL(ip_rcv); EXPORT_SYMBOL(ip_statistics); |