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authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-13 17:40:34 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-13 17:40:34 +0900
commit42a2d923cc349583ebf6fdd52a7d35e1c2f7e6bd (patch)
tree2b2b0c03b5389c1301800119333967efafd994ca /net/ipv4/udp.c
parent5cbb3d216e2041700231bcfc383ee5f8b7fc8b74 (diff)
parent75ecab1df14d90e86cebef9ec5c76befde46e65f (diff)
downloadlinux-42a2d923cc349583ebf6fdd52a7d35e1c2f7e6bd.tar.bz2
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: 1) The addition of nftables. No longer will we need protocol aware firewall filtering modules, it can all live in userspace. At the core of nftables is a, for lack of a better term, virtual machine that executes byte codes to inspect packet or metadata (arriving interface index, etc.) and make verdict decisions. Besides support for loading packet contents and comparing them, the interpreter supports lookups in various datastructures as fundamental operations. For example sets are supports, and therefore one could create a set of whitelist IP address entries which have ACCEPT verdicts attached to them, and use the appropriate byte codes to do such lookups. Since the interpreted code is composed in userspace, userspace can do things like optimize things before giving it to the kernel. Another major improvement is the capability of atomically updating portions of the ruleset. In the existing netfilter implementation, one has to update the entire rule set in order to make a change and this is very expensive. Userspace tools exist to create nftables rules using existing netfilter rule sets, but both kernel implementations will need to co-exist for quite some time as we transition from the old to the new stuff. Kudos to Patrick McHardy, Pablo Neira Ayuso, and others who have worked so hard on this. 2) Daniel Borkmann and Hannes Frederic Sowa made several improvements to our pseudo-random number generator, mostly used for things like UDP port randomization and netfitler, amongst other things. In particular the taus88 generater is updated to taus113, and test cases are added. 3) Support 64-bit rates in HTB and TBF schedulers, from Eric Dumazet and Yang Yingliang. 4) Add support for new 577xx tigon3 chips to tg3 driver, from Nithin Sujir. 5) Fix two fatal flaws in TCP dynamic right sizing, from Eric Dumazet, Neal Cardwell, and Yuchung Cheng. 6) Allow IP_TOS and IP_TTL to be specified in sendmsg() ancillary control message data, much like other socket option attributes. From Francesco Fusco. 7) Allow applications to specify a cap on the rate computed automatically by the kernel for pacing flows, via a new SO_MAX_PACING_RATE socket option. From Eric Dumazet. 8) Make the initial autotuned send buffer sizing in TCP more closely reflect actual needs, from Eric Dumazet. 9) Currently early socket demux only happens for TCP sockets, but we can do it for connected UDP sockets too. Implementation from Shawn Bohrer. 10) Refactor inet socket demux with the goal of improving hash demux performance for listening sockets. With the main goals being able to use RCU lookups on even request sockets, and eliminating the listening lock contention. From Eric Dumazet. 11) The bonding layer has many demuxes in it's fast path, and an RCU conversion was started back in 3.11, several changes here extend the RCU usage to even more locations. From Ding Tianhong and Wang Yufen, based upon suggestions by Nikolay Aleksandrov and Veaceslav Falico. 12) Allow stackability of segmentation offloads to, in particular, allow segmentation offloading over tunnels. From Eric Dumazet. 13) Significantly improve the handling of secret keys we input into the various hash functions in the inet hashtables, TCP fast open, as well as syncookies. From Hannes Frederic Sowa. The key fundamental operation is "net_get_random_once()" which uses static keys. Hannes even extended this to ipv4/ipv6 fragmentation handling and our generic flow dissector. 14) The generic driver layer takes care now to set the driver data to NULL on device removal, so it's no longer necessary for drivers to explicitly set it to NULL any more. Many drivers have been cleaned up in this way, from Jingoo Han. 15) Add a BPF based packet scheduler classifier, from Daniel Borkmann. 16) Improve CRC32 interfaces and generic SKB checksum iterators so that SCTP's checksumming can more cleanly be handled. Also from Daniel Borkmann. 17) Add a new PMTU discovery mode, IP_PMTUDISC_INTERFACE, which forces using the interface MTU value. This helps avoid PMTU attacks, particularly on DNS servers. From Hannes Frederic Sowa. 18) Use generic XPS for transmit queue steering rather than internal (re-)implementation in virtio-net. From Jason Wang. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits) random32: add test cases for taus113 implementation random32: upgrade taus88 generator to taus113 from errata paper random32: move rnd_state to linux/random.h random32: add prandom_reseed_late() and call when nonblocking pool becomes initialized random32: add periodic reseeding random32: fix off-by-one in seeding requirement PHY: Add RTL8201CP phy_driver to realtek xtsonic: add missing platform_set_drvdata() in xtsonic_probe() macmace: add missing platform_set_drvdata() in mace_probe() ethernet/arc/arc_emac: add missing platform_set_drvdata() in arc_emac_probe() ipv6: protect for_each_sk_fl_rcu in mem_check with rcu_read_lock_bh vlan: Implement vlan_dev_get_egress_qos_mask as an inline. ixgbe: add warning when max_vfs is out of range. igb: Update link modes display in ethtool netfilter: push reasm skb through instead of original frag skbs ip6_output: fragment outgoing reassembled skb properly MAINTAINERS: mv643xx_eth: take over maintainership from Lennart net_sched: tbf: support of 64bit rates ixgbe: deleting dfwd stations out of order can cause null ptr deref ixgbe: fix build err, num_rx_queues is only available with CONFIG_RPS ...
Diffstat (limited to 'net/ipv4/udp.c')
-rw-r--r--net/ipv4/udp.c235
1 files changed, 208 insertions, 27 deletions
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 0ca44df51ee9..89909dd730dd 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -103,6 +103,7 @@
#include <linux/seq_file.h>
#include <net/net_namespace.h>
#include <net/icmp.h>
+#include <net/inet_hashtables.h>
#include <net/route.h>
#include <net/checksum.h>
#include <net/xfrm.h>
@@ -219,7 +220,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
unsigned short first, last;
DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);
- inet_get_local_port_range(&low, &high);
+ inet_get_local_port_range(net, &low, &high);
remaining = (high - low) + 1;
rand = net_random();
@@ -406,6 +407,18 @@ static inline int compute_score2(struct sock *sk, struct net *net,
return score;
}
+static unsigned int udp_ehashfn(struct net *net, const __be32 laddr,
+ const __u16 lport, const __be32 faddr,
+ const __be16 fport)
+{
+ static u32 udp_ehash_secret __read_mostly;
+
+ net_get_random_once(&udp_ehash_secret, sizeof(udp_ehash_secret));
+
+ return __inet_ehashfn(laddr, lport, faddr, fport,
+ udp_ehash_secret + net_hash_mix(net));
+}
+
/* called with read_rcu_lock() */
static struct sock *udp4_lib_lookup2(struct net *net,
@@ -429,8 +442,8 @@ begin:
badness = score;
reuseport = sk->sk_reuseport;
if (reuseport) {
- hash = inet_ehashfn(net, daddr, hnum,
- saddr, sport);
+ hash = udp_ehashfn(net, daddr, hnum,
+ saddr, sport);
matches = 1;
}
} else if (score == badness && reuseport) {
@@ -510,8 +523,8 @@ begin:
badness = score;
reuseport = sk->sk_reuseport;
if (reuseport) {
- hash = inet_ehashfn(net, daddr, hnum,
- saddr, sport);
+ hash = udp_ehashfn(net, daddr, hnum,
+ saddr, sport);
matches = 1;
}
} else if (score == badness && reuseport) {
@@ -565,6 +578,26 @@ struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
}
EXPORT_SYMBOL_GPL(udp4_lib_lookup);
+static inline bool __udp_is_mcast_sock(struct net *net, struct sock *sk,
+ __be16 loc_port, __be32 loc_addr,
+ __be16 rmt_port, __be32 rmt_addr,
+ int dif, unsigned short hnum)
+{
+ struct inet_sock *inet = inet_sk(sk);
+
+ if (!net_eq(sock_net(sk), net) ||
+ udp_sk(sk)->udp_port_hash != hnum ||
+ (inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
+ (inet->inet_dport != rmt_port && inet->inet_dport) ||
+ (inet->inet_rcv_saddr && inet->inet_rcv_saddr != loc_addr) ||
+ ipv6_only_sock(sk) ||
+ (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
+ return false;
+ if (!ip_mc_sf_allow(sk, loc_addr, rmt_addr, dif))
+ return false;
+ return true;
+}
+
static inline struct sock *udp_v4_mcast_next(struct net *net, struct sock *sk,
__be16 loc_port, __be32 loc_addr,
__be16 rmt_port, __be32 rmt_addr,
@@ -575,20 +608,11 @@ static inline struct sock *udp_v4_mcast_next(struct net *net, struct sock *sk,
unsigned short hnum = ntohs(loc_port);
sk_nulls_for_each_from(s, node) {
- struct inet_sock *inet = inet_sk(s);
-
- if (!net_eq(sock_net(s), net) ||
- udp_sk(s)->udp_port_hash != hnum ||
- (inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
- (inet->inet_dport != rmt_port && inet->inet_dport) ||
- (inet->inet_rcv_saddr &&
- inet->inet_rcv_saddr != loc_addr) ||
- ipv6_only_sock(s) ||
- (s->sk_bound_dev_if && s->sk_bound_dev_if != dif))
- continue;
- if (!ip_mc_sf_allow(s, loc_addr, rmt_addr, dif))
- continue;
- goto found;
+ if (__udp_is_mcast_sock(net, s,
+ loc_port, loc_addr,
+ rmt_port, rmt_addr,
+ dif, hnum))
+ goto found;
}
s = NULL;
found:
@@ -855,6 +879,8 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
ipc.opt = NULL;
ipc.tx_flags = 0;
+ ipc.ttl = 0;
+ ipc.tos = -1;
getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
@@ -938,7 +964,7 @@ int udp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
faddr = ipc.opt->opt.faddr;
connected = 0;
}
- tos = RT_TOS(inet->tos);
+ tos = get_rttos(&ipc, inet);
if (sock_flag(sk, SOCK_LOCALROUTE) ||
(msg->msg_flags & MSG_DONTROUTE) ||
(ipc.opt && ipc.opt->opt.is_strictroute)) {
@@ -1403,8 +1429,10 @@ static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
int rc;
- if (inet_sk(sk)->inet_daddr)
+ if (inet_sk(sk)->inet_daddr) {
sock_rps_save_rxhash(sk, skb);
+ sk_mark_napi_id(sk, skb);
+ }
rc = sock_queue_rcv_skb(sk, skb);
if (rc < 0) {
@@ -1528,7 +1556,7 @@ int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
rc = 0;
- ipv4_pktinfo_prepare(skb);
+ ipv4_pktinfo_prepare(sk, skb);
bh_lock_sock(sk);
if (!sock_owned_by_user(sk))
rc = __udp_queue_rcv_skb(sk, skb);
@@ -1577,6 +1605,14 @@ static void flush_stack(struct sock **stack, unsigned int count,
kfree_skb(skb1);
}
+static void udp_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb_dst(skb);
+
+ dst_hold(dst);
+ sk->sk_rx_dst = dst;
+}
+
/*
* Multicasts and broadcasts go to each listener.
*
@@ -1705,16 +1741,32 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
if (udp4_csum_init(skb, uh, proto))
goto csum_error;
- if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
- return __udp4_lib_mcast_deliver(net, skb, uh,
- saddr, daddr, udptable);
+ if (skb->sk) {
+ int ret;
+ sk = skb->sk;
+
+ if (unlikely(sk->sk_rx_dst == NULL))
+ udp_sk_rx_dst_set(sk, skb);
- sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
+ ret = udp_queue_rcv_skb(sk, skb);
+
+ /* a return value > 0 means to resubmit the input, but
+ * it wants the return to be -protocol, or 0
+ */
+ if (ret > 0)
+ return -ret;
+ return 0;
+ } else {
+ if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
+ return __udp4_lib_mcast_deliver(net, skb, uh,
+ saddr, daddr, udptable);
+
+ sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
+ }
if (sk != NULL) {
int ret;
- sk_mark_napi_id(sk, skb);
ret = udp_queue_rcv_skb(sk, skb);
sock_put(sk);
@@ -1768,6 +1820,135 @@ drop:
return 0;
}
+/* We can only early demux multicast if there is a single matching socket.
+ * If more than one socket found returns NULL
+ */
+static struct sock *__udp4_lib_mcast_demux_lookup(struct net *net,
+ __be16 loc_port, __be32 loc_addr,
+ __be16 rmt_port, __be32 rmt_addr,
+ int dif)
+{
+ struct sock *sk, *result;
+ struct hlist_nulls_node *node;
+ unsigned short hnum = ntohs(loc_port);
+ unsigned int count, slot = udp_hashfn(net, hnum, udp_table.mask);
+ struct udp_hslot *hslot = &udp_table.hash[slot];
+
+ rcu_read_lock();
+begin:
+ count = 0;
+ result = NULL;
+ sk_nulls_for_each_rcu(sk, node, &hslot->head) {
+ if (__udp_is_mcast_sock(net, sk,
+ loc_port, loc_addr,
+ rmt_port, rmt_addr,
+ dif, hnum)) {
+ result = sk;
+ ++count;
+ }
+ }
+ /*
+ * if the nulls value we got at the end of this lookup is
+ * not the expected one, we must restart lookup.
+ * We probably met an item that was moved to another chain.
+ */
+ if (get_nulls_value(node) != slot)
+ goto begin;
+
+ if (result) {
+ if (count != 1 ||
+ unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
+ result = NULL;
+ else if (unlikely(!__udp_is_mcast_sock(net, result,
+ loc_port, loc_addr,
+ rmt_port, rmt_addr,
+ dif, hnum))) {
+ sock_put(result);
+ result = NULL;
+ }
+ }
+ rcu_read_unlock();
+ return result;
+}
+
+/* For unicast we should only early demux connected sockets or we can
+ * break forwarding setups. The chains here can be long so only check
+ * if the first socket is an exact match and if not move on.
+ */
+static struct sock *__udp4_lib_demux_lookup(struct net *net,
+ __be16 loc_port, __be32 loc_addr,
+ __be16 rmt_port, __be32 rmt_addr,
+ int dif)
+{
+ struct sock *sk, *result;
+ struct hlist_nulls_node *node;
+ unsigned short hnum = ntohs(loc_port);
+ unsigned int hash2 = udp4_portaddr_hash(net, loc_addr, hnum);
+ unsigned int slot2 = hash2 & udp_table.mask;
+ struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
+ INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr)
+ const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
+
+ rcu_read_lock();
+ result = NULL;
+ udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
+ if (INET_MATCH(sk, net, acookie,
+ rmt_addr, loc_addr, ports, dif))
+ result = sk;
+ /* Only check first socket in chain */
+ break;
+ }
+
+ if (result) {
+ if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
+ result = NULL;
+ else if (unlikely(!INET_MATCH(sk, net, acookie,
+ rmt_addr, loc_addr,
+ ports, dif))) {
+ sock_put(result);
+ result = NULL;
+ }
+ }
+ rcu_read_unlock();
+ return result;
+}
+
+void udp_v4_early_demux(struct sk_buff *skb)
+{
+ const struct iphdr *iph = ip_hdr(skb);
+ const struct udphdr *uh = udp_hdr(skb);
+ struct sock *sk;
+ struct dst_entry *dst;
+ struct net *net = dev_net(skb->dev);
+ int dif = skb->dev->ifindex;
+
+ /* validate the packet */
+ if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct udphdr)))
+ return;
+
+ if (skb->pkt_type == PACKET_BROADCAST ||
+ skb->pkt_type == PACKET_MULTICAST)
+ sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr,
+ uh->source, iph->saddr, dif);
+ else if (skb->pkt_type == PACKET_HOST)
+ sk = __udp4_lib_demux_lookup(net, uh->dest, iph->daddr,
+ uh->source, iph->saddr, dif);
+ else
+ return;
+
+ if (!sk)
+ return;
+
+ skb->sk = sk;
+ skb->destructor = sock_edemux;
+ dst = sk->sk_rx_dst;
+
+ if (dst)
+ dst = dst_check(dst, 0);
+ if (dst)
+ skb_dst_set_noref(skb, dst);
+}
+
int udp_rcv(struct sk_buff *skb)
{
return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP);