Phonet: proc interface for port range

Phonet endpoints are bound to individual ports.
This provides a /proc/sys/net/phonet (or sysctl) interface for
selecting the range of automatically allocated ports (much like the
ip_local_port_range with IPv4).

Signed-off-by: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/phonet/phonet.h b/include/net/phonet/phonet.h
index d3957d3..1c6f7e7 100644 (file)
--- a/include/net/phonet/phonet.h
+++ b/include/net/phonet/phonet.h
@@ -47,6 +47,7 @@ static inline struct pn_sock *pn_sk(struct sock *sk)
 extern const struct proto_ops phonet_dgram_ops;
 
 struct sock *pn_find_sock_by_sa(const struct sockaddr_pn *sa);
+void phonet_get_local_port_range(int *min, int *max);
 void pn_sock_hash(struct sock *sk);
 void pn_sock_unhash(struct sock *sk);
 int pn_sock_get_port(struct sock *sk, unsigned short sport);
@@ -97,6 +98,8 @@ struct phonet_protocol {
 int phonet_proto_register(int protocol, struct phonet_protocol *pp);
 void phonet_proto_unregister(int protocol, struct phonet_protocol *pp);
 
+int phonet_sysctl_init(void);
+void phonet_sysctl_exit(void);
 void phonet_netlink_register(void);
 int isi_register(void);
 void isi_unregister(void);

diff --git a/net/phonet/Makefile b/net/phonet/Makefile
index d218abc..ae9c3ed 100644 (file)
--- a/net/phonet/Makefile
+++ b/net/phonet/Makefile
@@ -5,4 +5,5 @@ phonet-objs := \
        pn_netlink.o \
        socket.o \
        datagram.o \
+       sysctl.o \
        af_phonet.o

diff --git a/net/phonet/af_phonet.c b/net/phonet/af_phonet.c
index 51397ff..50dc258 100644 (file)
--- a/net/phonet/af_phonet.c
+++ b/net/phonet/af_phonet.c
@@ -350,6 +350,7 @@ static int __init phonet_init(void)
        phonet_device_init();
        dev_add_pack(&phonet_packet_type);
        phonet_netlink_register();
+       phonet_sysctl_init();
 
        err = isi_register();
        if (err)
@@ -357,6 +358,7 @@ static int __init phonet_init(void)
        return 0;
 
 err:
+       phonet_sysctl_exit();
        sock_unregister(AF_PHONET);
        dev_remove_pack(&phonet_packet_type);
        phonet_device_exit();
@@ -366,6 +368,7 @@ err:
 static void __exit phonet_exit(void)
 {
        isi_unregister();
+       phonet_sysctl_exit();
        sock_unregister(AF_PHONET);
        dev_remove_pack(&phonet_packet_type);
        phonet_device_exit();

diff --git a/net/phonet/socket.c b/net/phonet/socket.c
index 99a4945..dfd4061 100644 (file)
--- a/net/phonet/socket.c
+++ b/net/phonet/socket.c
@@ -273,8 +273,9 @@ int pn_sock_get_port(struct sock *sk, unsigned short sport)
 
        if (!sport) {
                /* search free port */
-               int port, pmin = 0x40, pmax = 0x7f;
+               int port, pmin, pmax;
 
+               phonet_get_local_port_range(&pmin, &pmax);
                for (port = pmin; port <= pmax; port++) {
                        port_cur++;
                        if (port_cur < pmin || port_cur > pmax)

diff --git a/net/phonet/sysctl.c b/net/phonet/sysctl.c
new file mode 100644 (file)
index 0000000..600a430
--- /dev/null
+++ b/net/phonet/sysctl.c
@@ -0,0 +1,113 @@
+/*
+ * File: sysctl.c
+ *
+ * Phonet /proc/sys/net/phonet interface implementation
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ *
+ * Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/seqlock.h>
+#include <linux/sysctl.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+
+#define DYNAMIC_PORT_MIN       0x40
+#define DYNAMIC_PORT_MAX       0x7f
+
+static DEFINE_SEQLOCK(local_port_range_lock);
+static int local_port_range_min[2] = {0, 0};
+static int local_port_range_max[2] = {1023, 1023};
+static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX};
+static struct ctl_table_header *phonet_table_hrd;
+
+static void set_local_port_range(int range[2])
+{
+       write_seqlock(&local_port_range_lock);
+       local_port_range[0] = range[0];
+       local_port_range[1] = range[1];
+       write_sequnlock(&local_port_range_lock);
+}
+
+void phonet_get_local_port_range(int *min, int *max)
+{
+       unsigned seq;
+       do {
+               seq = read_seqbegin(&local_port_range_lock);
+               if (min)
+                       *min = local_port_range[0];
+               if (max)
+                       *max = local_port_range[1];
+       } while (read_seqretry(&local_port_range_lock, seq));
+}
+
+static int proc_local_port_range(ctl_table *table, int write, struct file *filp,
+                               void __user *buffer,
+                               size_t *lenp, loff_t *ppos)
+{
+       int ret;
+       int range[2] = {local_port_range[0], local_port_range[1]};
+       ctl_table tmp = {
+               .data = &range,
+               .maxlen = sizeof(range),
+               .mode = table->mode,
+               .extra1 = &local_port_range_min,
+               .extra2 = &local_port_range_max,
+       };
+
+       ret = proc_dointvec_minmax(&tmp, write, filp, buffer, lenp, ppos);
+
+       if (write && ret == 0) {
+               if (range[1] < range[0])
+                       ret = -EINVAL;
+               else
+                       set_local_port_range(range);
+       }
+
+       return ret;
+}
+
+static struct ctl_table phonet_table[] = {
+       {
+               .ctl_name       = CTL_UNNUMBERED,
+               .procname       = "local_port_range",
+               .data           = &local_port_range,
+               .maxlen         = sizeof(local_port_range),
+               .mode           = 0644,
+               .proc_handler   = &proc_local_port_range,
+               .strategy       = NULL,
+       },
+       { .ctl_name = 0 }
+};
+
+struct ctl_path phonet_ctl_path[] = {
+       { .procname = "net", .ctl_name = CTL_NET, },
+       { .procname = "phonet", .ctl_name = CTL_UNNUMBERED, },
+       { },
+};
+
+int __init phonet_sysctl_init(void)
+{
+       phonet_table_hrd = register_sysctl_paths(phonet_ctl_path, phonet_table);
+       return phonet_table_hrd == NULL ? -ENOMEM : 0;
+}
+
+void phonet_sysctl_exit(void)
+{
+       unregister_sysctl_table(phonet_table_hrd);
+}