[INET6_HASHTABLES]: Move inet6_lookup functions to net/ipv6/inet6_hashtables.c

Doing this we allow tcp_diag to support IPV6 even if tcp_diag is compiled
statically and IPV6 is compiled as a module, removing the previous restriction
while not building any IPV6 code if it is not selected.

Now to work on the tcpdiag_register infrastructure and then to rename the whole
thing to inetdiag, reflecting its by then completely generic nature.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 190 insertions, 157 deletions

diff --git a/include/net/inet6_hashtables.h b/include/net/inet6_hashtables.h
index 297c2b16967a..03df3b157960 100644
--- a/include/net/inet6_hashtables.h
+++ b/include/net/inet6_hashtables.h
@@ -14,13 +14,117 @@
 #ifndef _INET6_HASHTABLES_H
 #define _INET6_HASHTABLES_H
 
+#include <linux/config.h>
+
+#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
+#include <linux/in6.h>
+#include <linux/ipv6.h>
 #include <linux/types.h>
 
-struct in6_addr;
+#include <net/ipv6.h>
+
 struct inet_hashinfo;
 
+/* I have no idea if this is a good hash for v6 or not. -DaveM */
+static inline int inet6_ehashfn(const struct in6_addr *laddr, const u16 lport,
+                                const struct in6_addr *faddr, const u16 fport,
+                                const int ehash_size)
+{
+        int hashent = (lport ^ fport);
+
+        hashent ^= (laddr->s6_addr32[3] ^ faddr->s6_addr32[3]);
+        hashent ^= hashent >> 16;
+        hashent ^= hashent >> 8;
+        return (hashent & (ehash_size - 1));
+}
+
+static inline int inet6_sk_ehashfn(const struct sock *sk, const int ehash_size)
+{
+        const struct inet_sock *inet = inet_sk(sk);
+        const struct ipv6_pinfo *np = inet6_sk(sk);
+        const struct in6_addr *laddr = &np->rcv_saddr;
+        const struct in6_addr *faddr = &np->daddr;
+        const __u16 lport = inet->num;
+        const __u16 fport = inet->dport;
+        return inet6_ehashfn(laddr, lport, faddr, fport, ehash_size);
+}
+
+/*
+ * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
+ * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
+ *
+ * The sockhash lock must be held as a reader here.
+ */
+static inline struct sock *
+                __inet6_lookup_established(struct inet_hashinfo *hashinfo,
+                                           const struct in6_addr *saddr,
+                                           const u16 sport,
+                                           const struct in6_addr *daddr,
+                                           const u16 hnum,
+                                           const int dif)
+{
+        struct sock *sk;
+        const struct hlist_node *node;
+        const __u32 ports = INET_COMBINED_PORTS(sport, hnum);
+        /* Optimize here for direct hit, only listening connections can
+         * have wildcards anyways.
+         */
+        const int hash = inet6_ehashfn(daddr, hnum, saddr, sport,
+                                       hashinfo->ehash_size);
+        struct inet_ehash_bucket *head = &hashinfo->ehash[hash];
+
+        read_lock(&head->lock);
+        sk_for_each(sk, node, &head->chain) {
+                /* For IPV6 do the cheaper port and family tests first. */
+                if (INET6_MATCH(sk, saddr, daddr, ports, dif))
+                        goto hit; /* You sunk my battleship! */
+        }
+        /* Must check for a TIME_WAIT'er before going to listener hash. */
+        sk_for_each(sk, node, &(head + hashinfo->ehash_size)->chain) {
+                const struct inet_timewait_sock *tw = inet_twsk(sk);
+
+                if(*((__u32 *)&(tw->tw_dport))  == ports        &&
+                   sk->sk_family                == PF_INET6) {
+                        const struct tcp6_timewait_sock *tcp6tw = tcp6_twsk(sk);
+
+                        if (ipv6_addr_equal(&tcp6tw->tw_v6_daddr, saddr)        &&
+                            ipv6_addr_equal(&tcp6tw->tw_v6_rcv_saddr, daddr)    &&
+                            (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif))
+                                goto hit;
+                }
+        }
+        read_unlock(&head->lock);
+        return NULL;
+
+hit:
+        sock_hold(sk);
+        read_unlock(&head->lock);
+        return sk;
+}
+
+extern struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
+                                          const struct in6_addr *daddr,
+                                          const unsigned short hnum,
+                                          const int dif);
+
+static inline struct sock *__inet6_lookup(struct inet_hashinfo *hashinfo,
+                                          const struct in6_addr *saddr,
+                                          const u16 sport,
+                                          const struct in6_addr *daddr,
+                                          const u16 hnum,
+                                          const int dif)
+{
+        struct sock *sk = __inet6_lookup_established(hashinfo, saddr, sport,
+                                                     daddr, hnum, dif);
+        if (sk)
+                return sk;
+
+        return inet6_lookup_listener(hashinfo, daddr, hnum, dif);
+}
+
 extern struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
                                  const struct in6_addr *saddr, const u16 sport,
                                  const struct in6_addr *daddr, const u16 dport,
                                  const int dif);
+#endif /* defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE) */
 #endif /* _INET6_HASHTABLES_H */
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index a79b4f9c10c5..960c02faf440 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -419,9 +419,7 @@ config IP_TCPDIAG
         ---help---
           Support for TCP socket monitoring interface used by native Linux
           tools such as ss. ss is included in iproute2, currently downloadable
-          at <http://developer.osdl.org/dev/iproute2>. If you want IPv6 or DCCP
-          support and have selected IPv6 or DCCP as a module, you need to build
-          this as a module too.
+          at <http://developer.osdl.org/dev/iproute2>. 
           
           If unsure, say Y.
 
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 5bccea2d81b4..6460eec834b7 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -23,3 +23,5 @@ obj-$(CONFIG_NETFILTER)	+= netfilter/
 obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
 
 obj-y += exthdrs_core.o
+
+obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
new file mode 100644
index 000000000000..01d5f46d4e40
--- /dev/null
+++ b/net/ipv6/inet6_hashtables.c
@@ -0,0 +1,81 @@
+/*
+ * INET         An implementation of the TCP/IP protocol suite for the LINUX
+ *              operating system.  INET is implemented using the BSD Socket
+ *              interface as the means of communication with the user level.
+ *
+ *              Generic INET6 transport hashtables
+ *
+ * Authors:     Lotsa people, from code originally in tcp
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+
+#include <linux/module.h>
+
+#include <net/inet_connection_sock.h>
+#include <net/inet_hashtables.h>
+#include <net/inet6_hashtables.h>
+
+struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
+                                   const struct in6_addr *daddr,
+                                   const unsigned short hnum, const int dif)
+{
+        struct sock *sk;
+        const struct hlist_node *node;
+        struct sock *result = NULL;
+        int score, hiscore = 0;
+
+        read_lock(&hashinfo->lhash_lock);
+        sk_for_each(sk, node, &hashinfo->listening_hash[inet_lhashfn(hnum)]) {
+                if (inet_sk(sk)->num == hnum && sk->sk_family == PF_INET6) {
+                        const struct ipv6_pinfo *np = inet6_sk(sk);
+                        
+                        score = 1;
+                        if (!ipv6_addr_any(&np->rcv_saddr)) {
+                                if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
+                                        continue;
+                                score++;
+                        }
+                        if (sk->sk_bound_dev_if) {
+                                if (sk->sk_bound_dev_if != dif)
+                                        continue;
+                                score++;
+                        }
+                        if (score == 3) {
+                                result = sk;
+                                break;
+                        }
+                        if (score > hiscore) {
+                                hiscore = score;
+                                result = sk;
+                        }
+                }
+        }
+        if (result)
+                sock_hold(result);
+        read_unlock(&hashinfo->lhash_lock);
+        return result;
+}
+
+EXPORT_SYMBOL_GPL(inet6_lookup_listener);
+
+struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
+                          const struct in6_addr *saddr, const u16 sport,
+                          const struct in6_addr *daddr, const u16 dport,
+                          const int dif)
+{
+        struct sock *sk;
+
+        local_bh_disable();
+        sk = __inet6_lookup(hashinfo, saddr, sport, daddr, ntohs(dport), dif);
+        local_bh_enable();
+
+        return sk;
+}
+
+EXPORT_SYMBOL_GPL(inet6_lookup);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 2bc7fafe7668..fb291b81cf63 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -47,6 +47,7 @@
 
 #include <net/tcp.h>
 #include <net/ndisc.h>
+#include <net/inet6_hashtables.h>
 #include <net/ipv6.h>
 #include <net/transp_v6.h>
 #include <net/addrconf.h>
@@ -75,30 +76,6 @@ static int	tcp_v6_xmit(struct sk_buff *skb, int ipfragok);
 static struct tcp_func ipv6_mapped;
 static struct tcp_func ipv6_specific;
 
-/* I have no idea if this is a good hash for v6 or not. -DaveM */
-static inline int inet6_ehashfn(const struct in6_addr *laddr, const u16 lport,
-                                const struct in6_addr *faddr, const u16 fport,
-                                const int ehash_size)
-{
-        int hashent = (lport ^ fport);
-
-        hashent ^= (laddr->s6_addr32[3] ^ faddr->s6_addr32[3]);
-        hashent ^= hashent>>16;
-        hashent ^= hashent>>8;
-        return (hashent & (ehash_size - 1));
-}
-
-static inline int inet6_sk_ehashfn(const struct sock *sk, const int ehash_size)
-{
-        const struct inet_sock *inet = inet_sk(sk);
-        const struct ipv6_pinfo *np = inet6_sk(sk);
-        const struct in6_addr *laddr = &np->rcv_saddr;
-        const struct in6_addr *faddr = &np->daddr;
-        const __u16 lport = inet->num;
-        const __u16 fport = inet->dport;
-        return inet6_ehashfn(laddr, lport, faddr, fport, ehash_size);
-}
-
 static inline int tcp_v6_bind_conflict(const struct sock *sk,
                                        const struct inet_bind_bucket *tb)
 {
@@ -259,135 +236,6 @@ static void tcp_v6_hash(struct sock *sk)
         }
 }
 
-static struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
-                                          const struct in6_addr *daddr,
-                                          const unsigned short hnum,
-                                          const int dif)
-{
-        struct sock *sk;
-        struct hlist_node *node;
-        struct sock *result = NULL;
-        int score, hiscore;
-
-        hiscore=0;
-        read_lock(&hashinfo->lhash_lock);
-        sk_for_each(sk, node, &hashinfo->listening_hash[inet_lhashfn(hnum)]) {
-                if (inet_sk(sk)->num == hnum && sk->sk_family == PF_INET6) {
-                        struct ipv6_pinfo *np = inet6_sk(sk);
-                        
-                        score = 1;
-                        if (!ipv6_addr_any(&np->rcv_saddr)) {
-                                if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
-                                        continue;
-                                score++;
-                        }
-                        if (sk->sk_bound_dev_if) {
-                                if (sk->sk_bound_dev_if != dif)
-                                        continue;
-                                score++;
-                        }
-                        if (score == 3) {
-                                result = sk;
-                                break;
-                        }
-                        if (score > hiscore) {
-                                hiscore = score;
-                                result = sk;
-                        }
-                }
-        }
-        if (result)
-                sock_hold(result);
-        read_unlock(&hashinfo->lhash_lock);
-        return result;
-}
-
-/* Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
- * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
- *
- * The sockhash lock must be held as a reader here.
- */
-
-static inline struct sock *
-                __inet6_lookup_established(struct inet_hashinfo *hashinfo,
-                                           const struct in6_addr *saddr,
-                                           const u16 sport,
-                                           const struct in6_addr *daddr,
-                                           const u16 hnum,
-                                           const int dif)
-{
-        struct sock *sk;
-        const struct hlist_node *node;
-        const __u32 ports = INET_COMBINED_PORTS(sport, hnum);
-        /* Optimize here for direct hit, only listening connections can
-         * have wildcards anyways.
-         */
-        const int hash = inet6_ehashfn(daddr, hnum, saddr, sport,
-                                       hashinfo->ehash_size);
-        struct inet_ehash_bucket *head = &hashinfo->ehash[hash];
-
-        read_lock(&head->lock);
-        sk_for_each(sk, node, &head->chain) {
-                /* For IPV6 do the cheaper port and family tests first. */
-                if (INET6_MATCH(sk, saddr, daddr, ports, dif))
-                        goto hit; /* You sunk my battleship! */
-        }
-        /* Must check for a TIME_WAIT'er before going to listener hash. */
-        sk_for_each(sk, node, &(head + hashinfo->ehash_size)->chain) {
-                const struct inet_timewait_sock *tw = inet_twsk(sk);
-
-                if(*((__u32 *)&(tw->tw_dport))  == ports        &&
-                   sk->sk_family                == PF_INET6) {
-                        const struct tcp6_timewait_sock *tcp6tw = tcp6_twsk(sk);
-
-                        if (ipv6_addr_equal(&tcp6tw->tw_v6_daddr, saddr)        &&
-                            ipv6_addr_equal(&tcp6tw->tw_v6_rcv_saddr, daddr)    &&
-                            (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif))
-                                goto hit;
-                }
-        }
-        read_unlock(&head->lock);
-        return NULL;
-
-hit:
-        sock_hold(sk);
-        read_unlock(&head->lock);
-        return sk;
-}
-
-
-static inline struct sock *__inet6_lookup(struct inet_hashinfo *hashinfo,
-                                          const struct in6_addr *saddr,
-                                          const u16 sport,
-                                          const struct in6_addr *daddr,
-                                          const u16 hnum,
-                                          const int dif)
-{
-        struct sock *sk = __inet6_lookup_established(hashinfo, saddr, sport,
-                                                     daddr, hnum, dif);
-        if (sk)
-                return sk;
-
-        return inet6_lookup_listener(hashinfo, daddr, hnum, dif);
-}
-
-inline struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
-                                 const struct in6_addr *saddr, const u16 sport,
-                                 const struct in6_addr *daddr, const u16 dport,
-                                 const int dif)
-{
-        struct sock *sk;
-
-        local_bh_disable();
-        sk = __inet6_lookup(hashinfo, saddr, sport, daddr, ntohs(dport), dif);
-        local_bh_enable();
-
-        return sk;
-}
-
-EXPORT_SYMBOL_GPL(inet6_lookup);
-
-
 /*
  * Open request hash tables.
  */