[PATCH 07/24] net, diet: Make ping sockets optional

[Andi Kleen <andi@firstfloor.org>]

From: Andi Kleen <ak@linux.intel.com>

This saves about 6k text/data. ping still works fine using raw
sockets like it always did.

   text	   data	    bss	    dec	    hex	filename
 268128	  11555	   7872	 287555	  46343	net/ipv4/built-in.o-noping
 273610	  11843	   8176	 293629	  47afd	net/ipv4/built-in.o-ping

Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 include/net/ping.h      | 15 +++++++++++----
 include/net/transp_v6.h |  2 --
 net/ipv4/Kconfig        |  5 +++++
 net/ipv4/Makefile       |  3 ++-
 net/ipv4/af_inet.c      |  9 ++++-----
 net/ipv4/icmp.c         |  1 +
 net/ipv4/ping.c         |  3 +++
 net/ipv6/Makefile       |  3 ++-
 net/ipv6/af_inet6.c     |  8 ++++++--
 9 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/include/net/ping.h b/include/net/ping.h
index 026479b..ca6b89d 100644
--- a/include/net/ping.h
+++ b/include/net/ping.h
@@ -71,7 +71,6 @@ void ping_unhash(struct sock *sk);
 int  ping_init_sock(struct sock *sk);
 void ping_close(struct sock *sk, long timeout);
 int  ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len);
-void ping_err(struct sk_buff *skb, int offset, u32 info);
 int  ping_getfrag(void *from, char *to, int offset, int fraglen, int odd,
 		  struct sk_buff *);
 
@@ -82,7 +81,6 @@ int  ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
 int  ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		     size_t len);
 int  ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
-void ping_rcv(struct sk_buff *skb);
 
 #ifdef CONFIG_PROC_FS
 struct ping_seq_afinfo {
@@ -100,12 +98,21 @@ void ping_seq_stop(struct seq_file *seq, void *v);
 int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo);
 void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo);
 
-int __init ping_proc_init(void);
-void ping_proc_exit(void);
 #endif
 
+#ifdef CONFIG_IP_PING
+void ping_rcv(struct sk_buff *skb);
+void ping_err(struct sk_buff *skb, int offset, u32 info);
 void __init ping_init(void);
 int  __init pingv6_init(void);
 void pingv6_exit(void);
+#else
+static inline void ping_init(void) {}
+static inline int pingv6_init(void) { return 0; }
+static inline void pingv6_exit(void) { }
+static inline void ping_err(struct sk_buff *skb, int offset, u32 info) {}
+static inline void ping_rcv(struct sk_buff *skb) {}
+#endif
+
 
 #endif /* _PING_H */
diff --git a/include/net/transp_v6.h b/include/net/transp_v6.h
index b927413..7a0e229 100644
--- a/include/net/transp_v6.h
+++ b/include/net/transp_v6.h
@@ -19,8 +19,6 @@ int ipv6_frag_init(void);
 void ipv6_frag_exit(void);
 
 /* transport protocols */
-int pingv6_init(void);
-void pingv6_exit(void);
 int rawv6_init(void);
 void rawv6_exit(void);
 int udpv6_init(void);
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 05c57f0..6146b1b 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -52,6 +52,11 @@ config IP_ADVANCED_ROUTER
 
 	  If unsure, say N here.
 
+config IP_PING
+	bool "IP: ping sockets"
+	---help---
+	  Enable ping sockets to enable suid-less ping.
+
 config IP_FIB_TRIE_STATS
 	bool "FIB TRIE statistics"
 	depends on IP_ADVANCED_ROUTER
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index f032688..756855c 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -11,9 +11,10 @@ obj-y     := route.o inetpeer.o protocol.o \
 	     tcp_offload.o datagram.o raw.o udp.o udplite.o \
 	     udp_offload.o arp.o icmp.o devinet.o af_inet.o igmp.o \
 	     fib_frontend.o fib_semantics.o fib_trie.o \
-	     inet_fragment.o ping.o ip_tunnel_core.o gre_offload.o
+	     inet_fragment.o ip_tunnel_core.o gre_offload.o
 
 obj-$(CONFIG_NET_IP_TUNNEL) += ip_tunnel.o
+obj-$(CONFIG_IP_PING) += ping.o
 obj-$(CONFIG_SYSCTL) += sysctl_net_ipv4.o
 obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_IP_MULTIPLE_TABLES) += fib_rules.o
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 8c54870..c275ce5 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1015,7 +1015,7 @@ static struct inet_protosw inetsw_array[] =
 		.no_check =   UDP_CSUM_DEFAULT,
 		.flags =      INET_PROTOSW_PERMANENT,
        },
-
+#ifdef CONFIG_IP_PING
        {
 		.type =       SOCK_DGRAM,
 		.protocol =   IPPROTO_ICMP,
@@ -1024,6 +1024,7 @@ static struct inet_protosw inetsw_array[] =
 		.no_check =   UDP_CSUM_DEFAULT,
 		.flags =      INET_PROTOSW_REUSE,
        },
+#endif
 
        {
 	       .type =       SOCK_RAW,
@@ -1719,7 +1720,9 @@ static int __init inet_init(void)
 	if (rc)
 		goto out_unregister_udp_proto;
 
+#ifdef CONFIG_IP_PING
 	rc = proto_register(&ping_prot, 1);
+#endif
 	if (rc)
 		goto out_unregister_raw_proto;
 
@@ -1836,15 +1839,11 @@ static int __init ipv4_proc_init(void)
 		goto out_tcp;
 	if (udp4_proc_init())
 		goto out_udp;
-	if (ping_proc_init())
-		goto out_ping;
 	if (ip_misc_proc_init())
 		goto out_misc;
 out:
 	return rc;
 out_misc:
-	ping_proc_exit();
-out_ping:
 	udp4_proc_exit();
 out_udp:
 	tcp4_proc_exit();
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 0134663..df3872b 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -989,6 +989,7 @@ void icmp_err(struct sk_buff *skb, u32 info)
 		return;
 	}
 
+	/* RED-PEN dead code? the if above will eat all. */
 	if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)
 		ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ICMP, 0);
 	else if (type == ICMP_REDIRECT)
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 8210964..3f79243 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -1206,6 +1206,9 @@ void ping_proc_exit(void)
 	unregister_pernet_subsys(&ping_v4_net_ops);
 }
 
+module_init(ping_proc_init);
+module_exit(ping_proc_init);
+
 #endif
 
 void __init ping_init(void)
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 2fe6836..6ff7cfd 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -7,13 +7,14 @@ obj-$(CONFIG_IPV6) += ipv6.o
 ipv6-objs :=	af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o \
 		addrlabel.o \
 		route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o udplite.o \
-		raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o ping.o \
+		raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o \
 		exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o
 
 ipv6-offload :=	ip6_offload.o tcpv6_offload.o udp_offload.o exthdrs_offload.o
 
 ipv6-$(CONFIG_SYSCTL) = sysctl_net_ipv6.o
 ipv6-$(CONFIG_IPV6_MROUTE) += ip6mr.o
+ipv6-$(CONFIG_IP_PING) += ping.o
 
 ipv6-$(CONFIG_XFRM) += xfrm6_policy.o xfrm6_state.o xfrm6_input.o \
 	xfrm6_output.o xfrm6_protocol.o
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index d935889..68ac214 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -861,16 +861,18 @@ static int __init inet6_init(void)
 	if (err)
 		goto out_unregister_udplite_proto;
 
+#ifdef CONFIG_IP_PING
 	err = proto_register(&pingv6_prot, 1);
 	if (err)
-		goto out_unregister_ping_proto;
+		goto out_unregister_raw_proto;
+#endif
 
 	/* We MUST register RAW sockets before we create the ICMP6,
 	 * IGMP6, or NDISC control sockets.
 	 */
 	err = rawv6_init();
 	if (err)
-		goto out_unregister_raw_proto;
+		goto out_unregister_ping_proto;
 
 	/* Register the family here so that the init calls below will
 	 * be able to create sockets. (?? is this dangerous ??)
@@ -1022,8 +1024,10 @@ register_pernet_fail:
 out_sock_register_fail:
 	rawv6_exit();
 out_unregister_ping_proto:
+#ifdef CONFIG_IP_PING
 	proto_unregister(&pingv6_prot);
 out_unregister_raw_proto:
+#endif
 	proto_unregister(&rawv6_prot);
 out_unregister_udplite_proto:
 	proto_unregister(&udplitev6_prot);
-- 
1.9.0