sctp: add sctp/remaddr table to complete RFC remote address table OID

Add support for RFC3873 remote address table OID.

      +--(5) sctpAssocRemAddrTable
      |   |
      |   |--(-) sctpAssocId (shared index)
      |   |
      |   +--(1) sctpAssocRemAddrType (index)
      .   |
      .   +--(2) sctpAssocRemAddr (index)
      .   |
          +--(3) sctpAssocRemAddrActive
          |
          +--(4) sctpAssocRemAddrHBActive
          |
          +--(5) sctpAssocRemAddrRTO
          |
          +--(6) sctpAssocRemAddrMaxPathRtx
          |
          +--(7) sctpAssocRemAddrRtx
          |
          +--(8) sctpAssocRemAddrStartTime

This patch places all the requsite data in /proc/net/sctp/remaddr.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 146 insertions, 0 deletions

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 90b1e8d23b16..5672d489e924 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -179,6 +179,8 @@ int sctp_eps_proc_init(void);
 void sctp_eps_proc_exit(void);
 int sctp_assocs_proc_init(void);
 void sctp_assocs_proc_exit(void);
+int sctp_remaddr_proc_init(void);
+void sctp_remaddr_proc_exit(void);
 
 
 /*
diff --git a/net/sctp/proc.c b/net/sctp/proc.c
index 0aba759cb9b7..5dd89831eceb 100644
--- a/net/sctp/proc.c
+++ b/net/sctp/proc.c
@@ -383,3 +383,144 @@ void sctp_assocs_proc_exit(void)
 {
         remove_proc_entry("assocs", proc_net_sctp);
 }
+
+static void *sctp_remaddr_seq_start(struct seq_file *seq, loff_t *pos)
+{
+        if (*pos >= sctp_assoc_hashsize)
+                return NULL;
+
+        if (*pos < 0)
+                *pos = 0;
+
+        if (*pos == 0)
+                seq_printf(seq, "ADDR ASSOC_ID HB_ACT RTO MAX_PATH_RTX "
+                                "REM_ADDR_RTX  START\n");
+
+        return (void *)pos;
+}
+
+static void *sctp_remaddr_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+        if (++*pos >= sctp_assoc_hashsize)
+                return NULL;
+
+        return pos;
+}
+
+static void sctp_remaddr_seq_stop(struct seq_file *seq, void *v)
+{
+        return;
+}
+
+static int sctp_remaddr_seq_show(struct seq_file *seq, void *v)
+{
+        struct sctp_hashbucket *head;
+        struct sctp_ep_common *epb;
+        struct sctp_association *assoc;
+        struct hlist_node *node;
+        struct sctp_transport *tsp;
+        int    hash = *(loff_t *)v;
+
+        if (hash >= sctp_assoc_hashsize)
+                return -ENOMEM;
+
+        head = &sctp_assoc_hashtable[hash];
+        sctp_local_bh_disable();
+        read_lock(&head->lock);
+        sctp_for_each_hentry(epb, node, &head->chain) {
+                assoc = sctp_assoc(epb);
+                list_for_each_entry(tsp, &assoc->peer.transport_addr_list,
+                                        transports) {
+                        /*
+                         * The remote address (ADDR)
+                         */
+                        tsp->af_specific->seq_dump_addr(seq, &tsp->ipaddr);
+                        seq_printf(seq, " ");
+
+                        /*
+                         * The association ID (ASSOC_ID)
+                         */
+                        seq_printf(seq, "%d ", tsp->asoc->assoc_id);
+
+                        /*
+                         * If the Heartbeat is active (HB_ACT)
+                         * Note: 1 = Active, 0 = Inactive
+                         */
+                        seq_printf(seq, "%d ", timer_pending(&tsp->hb_timer));
+
+                        /*
+                         * Retransmit time out (RTO)
+                         */
+                        seq_printf(seq, "%lu ", tsp->rto);
+
+                        /*
+                         * Maximum path retransmit count (PATH_MAX_RTX)
+                         */
+                        seq_printf(seq, "%d ", tsp->pathmaxrxt);
+
+                        /*
+                         * remote address retransmit count (REM_ADDR_RTX)
+                         * Note: We don't have a way to tally this at the moment
+                         * so lets just leave it as zero for the moment
+                         */
+                        seq_printf(seq, "0 ");
+
+                        /*
+                         * remote address start time (START).  This is also not
+                         * currently implemented, but we can record it with a
+                         * jiffies marker in a subsequent patch
+                         */
+                        seq_printf(seq, "0");
+
+                        seq_printf(seq, "\n");
+                }
+        }
+
+        read_unlock(&head->lock);
+        sctp_local_bh_enable();
+
+        return 0;
+
+}
+
+static const struct seq_operations sctp_remaddr_ops = {
+        .start = sctp_remaddr_seq_start,
+        .next  = sctp_remaddr_seq_next,
+        .stop  = sctp_remaddr_seq_stop,
+        .show  = sctp_remaddr_seq_show,
+};
+
+/* Cleanup the proc fs entry for 'remaddr' object. */
+void sctp_remaddr_proc_exit(void)
+{
+        remove_proc_entry("remaddr", proc_net_sctp);
+}
+
+static int sctp_remaddr_seq_open(struct inode *inode, struct file *file)
+{
+        return seq_open(file, &sctp_remaddr_ops);
+}
+
+static const struct file_operations sctp_remaddr_seq_fops = {
+        .open = sctp_remaddr_seq_open,
+        .read = seq_read,
+        .llseek = seq_lseek,
+        .release = seq_release,
+};
+
+int __init sctp_remaddr_proc_init(void)
+{
+        struct proc_dir_entry *p;
+
+        p = create_proc_entry("remaddr", S_IRUGO, proc_net_sctp);
+        if (!p)
+                return -ENOMEM;
+        p->proc_fops = &sctp_remaddr_seq_fops;
+
+        return 0;
+}
+
+void sctp_assoc_proc_exit(void)
+{
+        remove_proc_entry("remaddr", proc_net_sctp);
+}
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 0ec234b762c2..b8bd9e014498 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -113,6 +113,8 @@ static __init int sctp_proc_init(void)
                 goto out_nomem;
         if (sctp_assocs_proc_init())
                 goto out_nomem;
+        if (sctp_remaddr_proc_init())
+                goto out_nomem;
 
         return 0;
 
@@ -129,6 +131,7 @@ static void sctp_proc_exit(void)
         sctp_snmp_proc_exit();
         sctp_eps_proc_exit();
         sctp_assocs_proc_exit();
+        sctp_remaddr_proc_exit();
 
         if (proc_net_sctp) {
                 proc_net_sctp = NULL;