[PATCH 3/3] net: ipv6: Implement /proc/net/icmp6.

[PATCH 3/3] net: ipv6: Implement /proc/net/icmp6.

[Lorenzo Colitti]

The format is based on /proc/net/icmp and /proc/net/{udp,raw}6.

Compiles and displays reasonable results with CONFIG_IPV6={n,m,y}
Couldn't figure out how to test without CONFIG_PROC_FS enabled.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
---
 include/net/ping.h |   8 +++++
 net/ipv4/ping.c    |  21 ++++++-----
 net/ipv6/ping.c    | 103 +++++++++++++++++++++++++++++++++++++++++------------
 3 files changed, 100 insertions(+), 32 deletions(-)

diff --git a/include/net/ping.h b/include/net/ping.h
index b9282f0..db04802 100644
--- a/include/net/ping.h
+++ b/include/net/ping.h
@@ -95,6 +95,14 @@ struct ping_seq_afinfo {
 	const struct seq_operations	seq_ops;
 };
 
+extern const struct file_operations ping_seq_fops;
+
+void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family);
+void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos);
+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);
+
 extern int __init ping_proc_init(void);
 extern void ping_proc_exit(void);
 #endif
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 8c2da9b..3552a45 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -1035,8 +1035,7 @@ static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
 	return pos ? NULL : sk;
 }
 
-static void *ping_seq_start(struct seq_file *seq, loff_t *pos,
-			    sa_family_t family)
+void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
 {
 	struct ping_iter_state *state = seq->private;
 	state->bucket = 0;
@@ -1046,13 +1045,14 @@ static void *ping_seq_start(struct seq_file *seq, loff_t *pos,
 
 	return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
 }
+EXPORT_SYMBOL_GPL(ping_seq_start);
 
 static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
 {
 	return ping_seq_start(seq, pos, AF_INET);
 }
 
-static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	struct sock *sk;
 
@@ -1064,11 +1064,13 @@ static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 	++*pos;
 	return sk;
 }
+EXPORT_SYMBOL_GPL(ping_seq_next);
 
-static void ping_seq_stop(struct seq_file *seq, void *v)
+void ping_seq_stop(struct seq_file *seq, void *v)
 {
 	read_unlock_bh(&ping_table.lock);
 }
+EXPORT_SYMBOL_GPL(ping_seq_stop);
 
 static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
 		int bucket, int *len)
@@ -1122,12 +1124,13 @@ static int ping_seq_open(struct inode *inode, struct file *file)
 			   sizeof(struct ping_iter_state));
 }
 
-static const struct file_operations ping_seq_fops = {
+const struct file_operations ping_seq_fops = {
 	.open		= ping_seq_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= seq_release_net,
 };
+EXPORT_SYMBOL_GPL(ping_seq_fops);
 
 static struct ping_seq_afinfo ping_v4_seq_afinfo = {
 	.name		= "icmp",
@@ -1141,7 +1144,7 @@ static struct ping_seq_afinfo ping_v4_seq_afinfo = {
 	},
 };
 
-static int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
+int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
 {
 	struct proc_dir_entry *p;
 	p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
@@ -1150,13 +1153,13 @@ static int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
 		return -ENOMEM;
 	return 0;
 }
+EXPORT_SYMBOL_GPL(ping_proc_register);
 
-static void ping_proc_unregister(struct net *net,
-				 struct ping_seq_afinfo *afinfo)
+void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
 {
 	remove_proc_entry(afinfo->name, net->proc_net);
 }
-
+EXPORT_SYMBOL_GPL(ping_proc_unregister);
 
 static int __net_init ping_v4_proc_init_net(struct net *net)
 {
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index a6462d6..46461b0 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -78,29 +78,6 @@ int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
 	return 0;
 }
 
-int __init pingv6_init(void)
-{
-	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
-	pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
-	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
-	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
-	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
-	return inet6_register_protosw(&pingv6_protosw);
-}
-
-/* This never gets called because it's not possible to unload the ipv6 module,
- * but just in case.
- */
-void pingv6_exit(void)
-{
-	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
-	pingv6_ops.ip6_datagram_recv_ctl = dummy_ip6_datagram_recv_ctl;
-	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
-	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
-	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
-	inet6_unregister_protosw(&pingv6_protosw);
-}
-
 int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		    size_t len)
 {
@@ -214,3 +191,83 @@ int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
 	return err;
 }
+
+#ifdef CONFIG_PROC_FS
+static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	return ping_seq_start(seq, pos, AF_INET6);
+}
+
+int ping_v6_seq_show(struct seq_file *seq, void *v)
+{
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
+	} else {
+		int bucket = ((struct ping_iter_state *) seq->private)->bucket;
+		struct inet_sock *inet = inet_sk(v);
+		__u16 srcp = ntohs(inet->inet_sport);
+		__u16 destp = ntohs(inet->inet_dport);
+		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
+	}
+	return 0;
+}
+
+static struct ping_seq_afinfo ping_v6_seq_afinfo = {
+	.name		= "icmp6",
+	.family		= AF_INET6,
+	.seq_fops       = &ping_seq_fops,
+	.seq_ops	= {
+		.start		= ping_v6_seq_start,
+		.show		= ping_v6_seq_show,
+		.next		= ping_seq_next,
+		.stop		= ping_seq_stop,
+	},
+};
+
+static int __net_init ping_v6_proc_init_net(struct net *net)
+{
+	return ping_proc_register(net, &ping_v6_seq_afinfo);
+}
+
+static void __net_init ping_v6_proc_exit_net(struct net *net)
+{
+	return ping_proc_unregister(net, &ping_v6_seq_afinfo);
+}
+
+static struct pernet_operations ping_v6_net_ops = {
+	.init = ping_v6_proc_init_net,
+	.exit = ping_v6_proc_exit_net,
+};
+#endif
+
+int __init pingv6_init(void)
+{
+	int ret;
+	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
+	pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
+	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
+	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
+	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
+#ifdef CONFIG_PROC_FS
+	ret = register_pernet_subsys(&ping_v6_net_ops);
+	if (ret)
+		return ret;
+#endif
+	return inet6_register_protosw(&pingv6_protosw);
+}
+
+/* This never gets called because it's not possible to unload the ipv6 module,
+ * but just in case.
+ */
+void pingv6_exit(void)
+{
+	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
+	pingv6_ops.ip6_datagram_recv_ctl = dummy_ip6_datagram_recv_ctl;
+	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
+	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
+	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
+#ifdef CONFIG_PROC_FS
+	unregister_pernet_subsys(&ping_v6_net_ops);
+#endif
+	inet6_unregister_protosw(&pingv6_protosw);
+}
-- 
1.8.2.1

Re: [PATCH 3/3] net: ipv6: Implement /proc/net/icmp6.

[Lorenzo Colitti]

On Tue, May 28, 2013 at 11:45 PM, Lorenzo Colitti <lorenzo@google.com> wrote:
> +int __init pingv6_init(void)
> +{
> +       int ret;
> +       pingv6_ops.ipv6_recv_error = ipv6_recv_error;
> +       pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
> +       pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
> +       pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
> +       pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
> +#ifdef CONFIG_PROC_FS
> +       ret = register_pernet_subsys(&ping_v6_net_ops);
> +       if (ret)
> +               return ret;

Nit: if register_pernet_subsys fails (ENOMEM?) then we return failure
and stop the IPv6 module from loading, but the function pointers
inside pingv6_ops are never cleared.

I don't think this has any impact, because if this happens, the proto
isn't registered, so there's no way to create an IPv6 socket and call
these function pointers. Still, for completeness' sake I'll shortly
send out another patch 3/3 that checks the result of
register_pernet_subsys before updating the function pointers. The
other two patches in the set don't need to change.

[PATCH 3/3] net: ipv6: Implement /proc/net/icmp6.

[Lorenzo Colitti]

The format is based on /proc/net/icmp and /proc/net/{udp,raw}6.

Compiles and displays reasonable results with CONFIG_IPV6={n,m,y}
Couldn't figure out how to test without CONFIG_PROC_FS enabled.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
---
 include/net/ping.h |   8 +++++
 net/ipv4/ping.c    |  21 ++++++-----
 net/ipv6/ping.c    | 102 +++++++++++++++++++++++++++++++++++++++++------------
 3 files changed, 99 insertions(+), 32 deletions(-)

diff --git a/include/net/ping.h b/include/net/ping.h
index b9282f0..db04802 100644
--- a/include/net/ping.h
+++ b/include/net/ping.h
@@ -95,6 +95,14 @@ struct ping_seq_afinfo {
 	const struct seq_operations	seq_ops;
 };
 
+extern const struct file_operations ping_seq_fops;
+
+void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family);
+void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos);
+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);
+
 extern int __init ping_proc_init(void);
 extern void ping_proc_exit(void);
 #endif
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 8c2da9b..3552a45 100644
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -1035,8 +1035,7 @@ static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
 	return pos ? NULL : sk;
 }
 
-static void *ping_seq_start(struct seq_file *seq, loff_t *pos,
-			    sa_family_t family)
+void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
 {
 	struct ping_iter_state *state = seq->private;
 	state->bucket = 0;
@@ -1046,13 +1045,14 @@ static void *ping_seq_start(struct seq_file *seq, loff_t *pos,
 
 	return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
 }
+EXPORT_SYMBOL_GPL(ping_seq_start);
 
 static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
 {
 	return ping_seq_start(seq, pos, AF_INET);
 }
 
-static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
 	struct sock *sk;
 
@@ -1064,11 +1064,13 @@ static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 	++*pos;
 	return sk;
 }
+EXPORT_SYMBOL_GPL(ping_seq_next);
 
-static void ping_seq_stop(struct seq_file *seq, void *v)
+void ping_seq_stop(struct seq_file *seq, void *v)
 {
 	read_unlock_bh(&ping_table.lock);
 }
+EXPORT_SYMBOL_GPL(ping_seq_stop);
 
 static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
 		int bucket, int *len)
@@ -1122,12 +1124,13 @@ static int ping_seq_open(struct inode *inode, struct file *file)
 			   sizeof(struct ping_iter_state));
 }
 
-static const struct file_operations ping_seq_fops = {
+const struct file_operations ping_seq_fops = {
 	.open		= ping_seq_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= seq_release_net,
 };
+EXPORT_SYMBOL_GPL(ping_seq_fops);
 
 static struct ping_seq_afinfo ping_v4_seq_afinfo = {
 	.name		= "icmp",
@@ -1141,7 +1144,7 @@ static struct ping_seq_afinfo ping_v4_seq_afinfo = {
 	},
 };
 
-static int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
+int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
 {
 	struct proc_dir_entry *p;
 	p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
@@ -1150,13 +1153,13 @@ static int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
 		return -ENOMEM;
 	return 0;
 }
+EXPORT_SYMBOL_GPL(ping_proc_register);
 
-static void ping_proc_unregister(struct net *net,
-				 struct ping_seq_afinfo *afinfo)
+void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
 {
 	remove_proc_entry(afinfo->name, net->proc_net);
 }
-
+EXPORT_SYMBOL_GPL(ping_proc_unregister);
 
 static int __net_init ping_v4_proc_init_net(struct net *net)
 {
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
index a6462d6..62ac5f2 100644
--- a/net/ipv6/ping.c
+++ b/net/ipv6/ping.c
@@ -78,29 +78,6 @@ int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
 	return 0;
 }
 
-int __init pingv6_init(void)
-{
-	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
-	pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
-	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
-	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
-	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
-	return inet6_register_protosw(&pingv6_protosw);
-}
-
-/* This never gets called because it's not possible to unload the ipv6 module,
- * but just in case.
- */
-void pingv6_exit(void)
-{
-	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
-	pingv6_ops.ip6_datagram_recv_ctl = dummy_ip6_datagram_recv_ctl;
-	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
-	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
-	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
-	inet6_unregister_protosw(&pingv6_protosw);
-}
-
 int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		    size_t len)
 {
@@ -214,3 +191,82 @@ int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
 	return err;
 }
+
+#ifdef CONFIG_PROC_FS
+static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
+{
+	return ping_seq_start(seq, pos, AF_INET6);
+}
+
+int ping_v6_seq_show(struct seq_file *seq, void *v)
+{
+	if (v == SEQ_START_TOKEN) {
+		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
+	} else {
+		int bucket = ((struct ping_iter_state *) seq->private)->bucket;
+		struct inet_sock *inet = inet_sk(v);
+		__u16 srcp = ntohs(inet->inet_sport);
+		__u16 destp = ntohs(inet->inet_dport);
+		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
+	}
+	return 0;
+}
+
+static struct ping_seq_afinfo ping_v6_seq_afinfo = {
+	.name		= "icmp6",
+	.family		= AF_INET6,
+	.seq_fops       = &ping_seq_fops,
+	.seq_ops	= {
+		.start		= ping_v6_seq_start,
+		.show		= ping_v6_seq_show,
+		.next		= ping_seq_next,
+		.stop		= ping_seq_stop,
+	},
+};
+
+static int __net_init ping_v6_proc_init_net(struct net *net)
+{
+	return ping_proc_register(net, &ping_v6_seq_afinfo);
+}
+
+static void __net_init ping_v6_proc_exit_net(struct net *net)
+{
+	return ping_proc_unregister(net, &ping_v6_seq_afinfo);
+}
+
+static struct pernet_operations ping_v6_net_ops = {
+	.init = ping_v6_proc_init_net,
+	.exit = ping_v6_proc_exit_net,
+};
+#endif
+
+int __init pingv6_init(void)
+{
+#ifdef CONFIG_PROC_FS
+	int ret = register_pernet_subsys(&ping_v6_net_ops);
+	if (ret)
+		return ret;
+#endif
+	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
+	pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
+	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
+	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
+	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
+	return inet6_register_protosw(&pingv6_protosw);
+}
+
+/* This never gets called because it's not possible to unload the ipv6 module,
+ * but just in case.
+ */
+void pingv6_exit(void)
+{
+	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
+	pingv6_ops.ip6_datagram_recv_ctl = dummy_ip6_datagram_recv_ctl;
+	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
+	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
+	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
+#ifdef CONFIG_PROC_FS
+	unregister_pernet_subsys(&ping_v6_net_ops);
+#endif
+	inet6_unregister_protosw(&pingv6_protosw);
+}
-- 
1.8.2.1

Re: [PATCH 3/3] net: ipv6: Implement /proc/net/icmp6.

[Cong Wang]

On Wed, 29 May 2013 at 02:31 GMT, Lorenzo Colitti <lorenzo@google.com> wrote:
> I don't think this has any impact, because if this happens, the proto
> isn't registered, so there's no way to create an IPv6 socket and call
> these function pointers. Still, for completeness' sake I'll shortly
> send out another patch 3/3 that checks the result of
> register_pernet_subsys before updating the function pointers. The
> other two patches in the set don't need to change.

You have to resend all of them, not just one, per netdev rules.

Re: [PATCH 3/3] net: ipv6: Implement /proc/net/icmp6.

[Lorenzo Colitti]

Ok, here's a new complete patchset.