@@ -31,6 +31,19 @@ menuconfig L2TP
If you don't need L2TP, say N. To compile all L2TP code as
modules, choose M here.
+config L2TP_DEBUGFS
+ tristate "L2TP debugfs support"
+ depends on L2TP && DEBUG_FS
+ help
+ Support for l2tp directory in debugfs filesystem. This may be
+ used to dump internal state of the l2tp drivers for problem
+ analysis.
+
+ If unsure, say 'Y'.
+
+ To compile this driver as a module, choose M here. The module
+ will be called l2tp_debugfs.
+
config L2TP_V3
bool "L2TPv3 support (EXPERIMENTAL)"
depends on EXPERIMENTAL && L2TP
@@ -9,3 +9,4 @@ obj-$(subst y,$(CONFIG_L2TP),$(CONFIG_PPPOL2TP)) += l2tp_ppp.o
obj-$(subst y,$(CONFIG_L2TP),$(CONFIG_L2TP_IP)) += l2tp_ip.o
obj-$(subst y,$(CONFIG_L2TP),$(CONFIG_L2TP_V3)) += l2tp_netlink.o
obj-$(subst y,$(CONFIG_L2TP),$(CONFIG_L2TP_ETH)) += l2tp_eth.o
+obj-$(subst y,$(CONFIG_L2TP),$(CONFIG_L2TP_DEBUGFS)) += l2tp_debugfs.o
@@ -133,7 +133,9 @@ struct l2tp_session {
void (*session_close)(struct l2tp_session *session);
void (*ref)(struct l2tp_session *session);
void (*deref)(struct l2tp_session *session);
-
+#ifdef CONFIG_L2TP_DEBUGFS
+ void (*show)(struct seq_file *m, void *priv);
+#endif
uint8_t priv[0]; /* private data */
};
@@ -166,7 +168,9 @@ struct l2tp_tunnel {
struct net *l2tp_net; /* the net we belong to */
atomic_t ref_count;
-
+#ifdef CONFIG_DEBUG_FS
+ void (*show)(struct seq_file *m, void *arg);
+#endif
int (*recv_payload_hook)(struct sk_buff *skb);
void (*old_sk_destruct)(struct sock *);
struct sock *sock; /* Parent socket */
new file mode 100644
@@ -0,0 +1,341 @@
+/*
+ * L2TP subsystem debugfs
+ *
+ * Copyright (c) 2010 Katalix Systems Ltd
+ *
+ * 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/module.h>
+#include <linux/skbuff.h>
+#include <linux/socket.h>
+#include <linux/hash.h>
+#include <linux/l2tp.h>
+#include <linux/in.h>
+#include <linux/etherdevice.h>
+#include <linux/spinlock.h>
+#include <linux/debugfs.h>
+#include <net/sock.h>
+#include <net/ip.h>
+#include <net/icmp.h>
+#include <net/udp.h>
+#include <net/inet_common.h>
+#include <net/inet_hashtables.h>
+#include <net/tcp_states.h>
+#include <net/protocol.h>
+#include <net/xfrm.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+
+#include "l2tp_core.h"
+
+static struct dentry *rootdir;
+static struct dentry *tunnels;
+
+struct l2tp_dfs_seq_data {
+ struct net *net;
+ int tunnel_idx; /* current tunnel */
+ int session_idx; /* index of session within current tunnel */
+ struct l2tp_tunnel *tunnel;
+ struct l2tp_session *session; /* NULL means get next tunnel */
+};
+
+static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd)
+{
+ pd->tunnel = l2tp_tunnel_find_nth(pd->net, pd->tunnel_idx);
+ pd->tunnel_idx++;
+}
+
+static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd)
+{
+ pd->session = l2tp_session_find_nth(pd->tunnel, pd->session_idx);
+ pd->session_idx++;
+
+ if (pd->session == NULL) {
+ pd->session_idx = 0;
+ l2tp_dfs_next_tunnel(pd);
+ }
+
+}
+
+static void *l2tp_dfs_seq_start(struct seq_file *m, loff_t *offs)
+{
+ struct l2tp_dfs_seq_data *pd = SEQ_START_TOKEN;
+ loff_t pos = *offs;
+
+ if (!pos)
+ goto out;
+
+ BUG_ON(m->private == NULL);
+ pd = m->private;
+
+ if (pd->tunnel == NULL)
+ l2tp_dfs_next_tunnel(pd);
+ else
+ l2tp_dfs_next_session(pd);
+
+ /* NULL tunnel and session indicates end of list */
+ if ((pd->tunnel == NULL) && (pd->session == NULL))
+ pd = NULL;
+
+out:
+ return pd;
+}
+
+
+static void *l2tp_dfs_seq_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ (*pos)++;
+ return NULL;
+}
+
+static void l2tp_dfs_seq_stop(struct seq_file *p, void *v)
+{
+ /* nothing to do */
+}
+
+static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v)
+{
+ struct l2tp_tunnel *tunnel = v;
+ int session_count = 0;
+ int hash;
+ struct hlist_node *walk;
+ struct hlist_node *tmp;
+
+ read_lock_bh(&tunnel->hlist_lock);
+ for (hash = 0; hash < L2TP_HASH_SIZE; hash++) {
+ hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) {
+ struct l2tp_session *session;
+
+ session = hlist_entry(walk, struct l2tp_session, hlist);
+ if (session->session_id == 0)
+ continue;
+
+ session_count++;
+ }
+ }
+ read_unlock_bh(&tunnel->hlist_lock);
+
+ seq_printf(m, "\nTUNNEL %u peer %u", tunnel->tunnel_id, tunnel->peer_tunnel_id);
+ if (tunnel->sock) {
+ struct inet_sock *inet = inet_sk(tunnel->sock);
+ seq_printf(m, " from " NIPQUAD_FMT " to " NIPQUAD_FMT "\n",
+ NIPQUAD(inet->inet_saddr), NIPQUAD(inet->inet_daddr));
+ if (tunnel->encap == L2TP_ENCAPTYPE_UDP)
+ seq_printf(m, " source port %hu, dest port %hu\n",
+ ntohs(inet->inet_sport), ntohs(inet->inet_dport));
+ }
+ seq_printf(m, " L2TPv%d, %s\n", tunnel->version,
+ tunnel->encap == L2TP_ENCAPTYPE_UDP ? "UDP" :
+ tunnel->encap == L2TP_ENCAPTYPE_IP ? "IP" :
+ "");
+ seq_printf(m, " %d sessions, refcnt %d/%d\n", session_count,
+ tunnel->sock ? atomic_read(&tunnel->sock->sk_refcnt) : 0,
+ atomic_read(&tunnel->ref_count));
+
+ seq_printf(m, " %08x rx %llu/%llu/%llu rx %llu/%llu/%llu\n",
+ tunnel->debug,
+ (unsigned long long)tunnel->stats.tx_packets,
+ (unsigned long long)tunnel->stats.tx_bytes,
+ (unsigned long long)tunnel->stats.tx_errors,
+ (unsigned long long)tunnel->stats.rx_packets,
+ (unsigned long long)tunnel->stats.rx_bytes,
+ (unsigned long long)tunnel->stats.rx_errors);
+
+ if (tunnel->show != NULL)
+ tunnel->show(m, tunnel);
+}
+
+static void l2tp_dfs_seq_session_show(struct seq_file *m, void *v)
+{
+ struct l2tp_session *session = v;
+
+ seq_printf(m, " SESSION %u, peer %u, %s\n", session->session_id,
+ session->peer_session_id,
+ session->pwtype == L2TP_PWTYPE_ETH ? "ETH" :
+ session->pwtype == L2TP_PWTYPE_PPP ? "PPP" :
+ "");
+ if (session->send_seq || session->recv_seq)
+ seq_printf(m, " nr %hu, ns %hu\n", session->nr, session->ns);
+ seq_printf(m, " refcnt %d\n", atomic_read(&session->ref_count));
+ seq_printf(m, " config %d/%d/%c/%c/%s/%s %08x %u\n",
+ session->mtu, session->mru,
+ session->recv_seq ? 'R' : '-',
+ session->send_seq ? 'S' : '-',
+ session->data_seq == 1 ? "IPSEQ" :
+ session->data_seq == 2 ? "DATASEQ" : "-",
+ session->lns_mode ? "LNS" : "LAC",
+ session->debug,
+ jiffies_to_msecs(session->reorder_timeout));
+ seq_printf(m, " offset %hu l2specific %hu/%hu\n",
+ session->offset, session->l2specific_type, session->l2specific_len);
+ if (session->cookie_len) {
+ seq_printf(m, " cookie %02x%02x%02x%02x",
+ session->cookie[0], session->cookie[1],
+ session->cookie[2], session->cookie[3]);
+ if (session->cookie_len == 8)
+ seq_printf(m, "%02x%02x%02x%02x",
+ session->cookie[4], session->cookie[5],
+ session->cookie[6], session->cookie[7]);
+ seq_printf(m, "\n");
+ }
+ if (session->peer_cookie_len) {
+ seq_printf(m, " peer cookie %02x%02x%02x%02x",
+ session->peer_cookie[0], session->peer_cookie[1],
+ session->peer_cookie[2], session->peer_cookie[3]);
+ if (session->peer_cookie_len == 8)
+ seq_printf(m, "%02x%02x%02x%02x",
+ session->peer_cookie[4], session->peer_cookie[5],
+ session->peer_cookie[6], session->peer_cookie[7]);
+ seq_printf(m, "\n");
+ }
+
+ seq_printf(m, " %hu/%hu tx %llu/%llu/%llu rx %llu/%llu/%llu\n",
+ session->nr, session->ns,
+ (unsigned long long)session->stats.tx_packets,
+ (unsigned long long)session->stats.tx_bytes,
+ (unsigned long long)session->stats.tx_errors,
+ (unsigned long long)session->stats.rx_packets,
+ (unsigned long long)session->stats.rx_bytes,
+ (unsigned long long)session->stats.rx_errors);
+
+ if (session->show != NULL)
+ session->show(m, session);
+}
+
+static int l2tp_dfs_seq_show(struct seq_file *m, void *v)
+{
+ struct l2tp_dfs_seq_data *pd = v;
+
+ /* display header on line 1 */
+ if (v == SEQ_START_TOKEN) {
+ seq_puts(m, "TUNNEL ID, peer ID from IP to IP\n");
+ seq_puts(m, " L2TPv2/L2TPv3, UDP/IP\n");
+ seq_puts(m, " sessions session-count, refcnt refcnt/sk->refcnt\n");
+ seq_puts(m, " debug tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
+ seq_puts(m, " SESSION ID, peer ID, PWTYPE\n");
+ seq_puts(m, " refcnt cnt\n");
+ seq_puts(m, " offset OFFSET l2specific TYPE/LEN\n");
+ seq_puts(m, " [ cookie ]\n");
+ seq_puts(m, " [ peer cookie ]\n");
+ seq_puts(m, " config mtu/mru/rcvseq/sendseq/dataseq/lns debug reorderto\n");
+ seq_puts(m, " nr/ns tx-pkts/bytes/errs rx-pkts/bytes/errs\n");
+ goto out;
+ }
+
+ /* Show the tunnel or session context */
+ if (pd->session == NULL)
+ l2tp_dfs_seq_tunnel_show(m, pd->tunnel);
+ else
+ l2tp_dfs_seq_session_show(m, pd->session);
+
+out:
+ return 0;
+}
+
+static const struct seq_operations l2tp_dfs_seq_ops = {
+ .start = l2tp_dfs_seq_start,
+ .next = l2tp_dfs_seq_next,
+ .stop = l2tp_dfs_seq_stop,
+ .show = l2tp_dfs_seq_show,
+};
+
+static int l2tp_dfs_seq_open(struct inode *inode, struct file *file)
+{
+ struct l2tp_dfs_seq_data *pd;
+ struct seq_file *seq;
+ int rc = -ENOMEM;
+
+ pd = kzalloc(GFP_KERNEL, sizeof(*pd));
+ if (pd == NULL)
+ goto out;
+
+ /* Derive the network namespace from the pid opening the
+ * file.
+ */
+ pd->net = get_net_ns_by_pid(current->pid);
+ if (IS_ERR(pd->net)) {
+ rc = -PTR_ERR(pd->net);
+ goto err_free_pd;
+ }
+
+ rc = seq_open(file, &l2tp_dfs_seq_ops);
+ if (rc)
+ goto err_free_net;
+
+ seq = file->private_data;
+ seq->private = pd;
+
+out:
+ return rc;
+
+err_free_net:
+ put_net(pd->net);
+err_free_pd:
+ kfree(pd);
+ goto out;
+}
+
+static int l2tp_dfs_seq_release(struct inode *inode, struct file *file)
+{
+ struct l2tp_dfs_seq_data *pd;
+ struct seq_file *seq;
+
+ seq = file->private_data;
+ pd = seq->private;
+ if (pd->net)
+ put_net(pd->net);
+ kfree(pd);
+ seq_release(inode, file);
+
+ return 0;
+}
+
+static const struct file_operations l2tp_dfs_fops = {
+ .owner = THIS_MODULE,
+ .open = l2tp_dfs_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = l2tp_dfs_seq_release,
+};
+
+static int __init l2tp_debugfs_init(void)
+{
+ int rc = 0;
+
+ rootdir = debugfs_create_dir("l2tp", NULL);
+ if (IS_ERR(rootdir)) {
+ rc = PTR_ERR(rootdir);
+ rootdir = NULL;
+ goto out;
+ }
+
+ tunnels = debugfs_create_file("tunnels", 0600, rootdir, NULL, &l2tp_dfs_fops);
+ if (tunnels == NULL)
+ rc = -EIO;
+
+ printk(KERN_INFO "L2TP debugfs support\n");
+
+out:
+ if (rc)
+ printk(KERN_WARNING "l2tp debugfs: unable to init\n");
+
+ return rc;
+}
+
+static void __exit l2tp_debugfs_exit(void)
+{
+ debugfs_remove(tunnels);
+ debugfs_remove(rootdir);
+}
+
+module_init(l2tp_debugfs_init);
+module_exit(l2tp_debugfs_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("James Chapman <jchapman@katalix.com>");
+MODULE_DESCRIPTION("L2TP debugfs driver");
+MODULE_VERSION("1.0");
@@ -172,6 +172,17 @@ static void l2tp_eth_delete(struct l2tp_session *session)
}
}
+#ifdef CONFIG_L2TP_DEBUGFS
+static void l2tp_eth_show(struct seq_file *m, void *arg)
+{
+ struct l2tp_session *session = arg;
+ struct l2tp_eth_sess *spriv = l2tp_session_priv(session);
+ struct net_device *dev = spriv->dev;
+
+ seq_printf(m, " interface %s\n", dev->name);
+}
+#endif
+
static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 peer_session_id, struct l2tp_session_cfg *cfg)
{
struct net_device *dev;
@@ -233,6 +244,9 @@ static int l2tp_eth_create(struct net *net, u32 tunnel_id, u32 session_id, u32 p
priv->tunnel_sock = tunnel->sock;
session->recv_skb = l2tp_eth_dev_recv;
session->session_close = l2tp_eth_delete;
+#ifdef CONFIG_L2TP_DEBUGFS
+ session->show = l2tp_eth_show;
+#endif
spriv = l2tp_session_priv(session);
spriv->dev = dev;
@@ -597,6 +597,20 @@ out:
return error;
}
+#ifdef CONFIG_L2TP_DEBUGFS
+static void pppol2tp_show(struct seq_file *m, void *arg)
+{
+ struct l2tp_session *session = arg;
+ struct pppol2tp_session *ps = l2tp_session_priv(session);
+
+ if (ps) {
+ struct pppox_sock *po = pppox_sk(ps->sock);
+ if (po)
+ seq_printf(m, " interface %s\n", ppp_dev_name(&po->chan));
+ }
+}
+#endif
+
/* connect() handler. Attach a PPPoX socket to a tunnel UDP socket
*/
static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
@@ -734,6 +748,9 @@ static int pppol2tp_connect(struct socket *sock, struct sockaddr *uservaddr,
session->recv_skb = pppol2tp_recv;
session->session_close = pppol2tp_session_close;
+#ifdef CONFIG_L2TP_DEBUGFS
+ session->show = pppol2tp_show;
+#endif
/* We need to know each time a skb is dropped from the reorder
* queue.
The existing pppol2tp driver exports debug info to /proc/net/pppol2tp. Rather than adding info to that file for the new functionality added in this patch series, we add new files in debugfs, leaving the old /proc file for backwards compatibility (L2TPv2 only). Currently only one file is provided: l2tp/tunnels, which lists internal debug info for all l2tp tunnels and sessions. More files may be added later. The info is for debug and problem analysis only - userspace apps should use netlink to obtain status about l2tp tunnels and sessions. Although debugfs does not support net namespaces, the tunnels and sessions dumped in l2tp/tunnels are only those in the net namespace of the process reading the file. Signed-off-by: James Chapman <jchapman@katalix.com> --- net/l2tp/Kconfig | 13 ++ net/l2tp/Makefile | 1 net/l2tp/l2tp_core.h | 8 + net/l2tp/l2tp_debugfs.c | 341 +++++++++++++++++++++++++++++++++++++++++++++++ net/l2tp/l2tp_eth.c | 14 ++ net/l2tp/l2tp_ppp.c | 17 ++ 6 files changed, 392 insertions(+), 2 deletions(-) create mode 100644 net/l2tp/l2tp_debugfs.c -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html