mirror of
https://github.com/torvalds/linux.git
synced 2024-11-14 08:02:07 +00:00
f726214d9b
Use l2tp_tunnel_get_nth() instead of l2tp_tunnel_find_nth(), to be safe
against concurrent tunnel deletion.
Use the same mechanism as in l2tp_ppp.c for dropping the reference
taken by l2tp_tunnel_get_nth(). That is, drop the reference just
before looking up the next tunnel. In case of error, drop the last
accessed tunnel in l2tp_dfs_seq_stop().
That was the last use of l2tp_tunnel_find_nth().
Fixes: 0ad6614048
("l2tp: Add debugfs files for dumping l2tp debug info")
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
312 lines
9.3 KiB
C
312 lines
9.3 KiB
C
/*
|
|
* L2TP internal definitions.
|
|
*
|
|
* Copyright (c) 2008,2009 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 version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#include <linux/refcount.h>
|
|
|
|
#ifndef _L2TP_CORE_H_
|
|
#define _L2TP_CORE_H_
|
|
|
|
/* Just some random numbers */
|
|
#define L2TP_TUNNEL_MAGIC 0x42114DDA
|
|
#define L2TP_SESSION_MAGIC 0x0C04EB7D
|
|
|
|
/* Per tunnel, session hash table size */
|
|
#define L2TP_HASH_BITS 4
|
|
#define L2TP_HASH_SIZE (1 << L2TP_HASH_BITS)
|
|
|
|
/* System-wide, session hash table size */
|
|
#define L2TP_HASH_BITS_2 8
|
|
#define L2TP_HASH_SIZE_2 (1 << L2TP_HASH_BITS_2)
|
|
|
|
struct sk_buff;
|
|
|
|
struct l2tp_stats {
|
|
atomic_long_t tx_packets;
|
|
atomic_long_t tx_bytes;
|
|
atomic_long_t tx_errors;
|
|
atomic_long_t rx_packets;
|
|
atomic_long_t rx_bytes;
|
|
atomic_long_t rx_seq_discards;
|
|
atomic_long_t rx_oos_packets;
|
|
atomic_long_t rx_errors;
|
|
atomic_long_t rx_cookie_discards;
|
|
};
|
|
|
|
struct l2tp_tunnel;
|
|
|
|
/* Describes a session. Contains information to determine incoming
|
|
* packets and transmit outgoing ones.
|
|
*/
|
|
struct l2tp_session_cfg {
|
|
enum l2tp_pwtype pw_type;
|
|
unsigned int data_seq:2; /* data sequencing level
|
|
* 0 => none, 1 => IP only,
|
|
* 2 => all
|
|
*/
|
|
unsigned int recv_seq:1; /* expect receive packets with
|
|
* sequence numbers? */
|
|
unsigned int send_seq:1; /* send packets with sequence
|
|
* numbers? */
|
|
unsigned int lns_mode:1; /* behave as LNS? LAC enables
|
|
* sequence numbers under
|
|
* control of LNS. */
|
|
int debug; /* bitmask of debug message
|
|
* categories */
|
|
u16 vlan_id; /* VLAN pseudowire only */
|
|
u16 l2specific_type; /* Layer 2 specific type */
|
|
u8 cookie[8]; /* optional cookie */
|
|
int cookie_len; /* 0, 4 or 8 bytes */
|
|
u8 peer_cookie[8]; /* peer's cookie */
|
|
int peer_cookie_len; /* 0, 4 or 8 bytes */
|
|
int reorder_timeout; /* configured reorder timeout
|
|
* (in jiffies) */
|
|
int mtu;
|
|
int mru;
|
|
char *ifname;
|
|
};
|
|
|
|
struct l2tp_session {
|
|
int magic; /* should be
|
|
* L2TP_SESSION_MAGIC */
|
|
long dead;
|
|
|
|
struct l2tp_tunnel *tunnel; /* back pointer to tunnel
|
|
* context */
|
|
u32 session_id;
|
|
u32 peer_session_id;
|
|
u8 cookie[8];
|
|
int cookie_len;
|
|
u8 peer_cookie[8];
|
|
int peer_cookie_len;
|
|
u16 l2specific_type;
|
|
u16 hdr_len;
|
|
u32 nr; /* session NR state (receive) */
|
|
u32 ns; /* session NR state (send) */
|
|
struct sk_buff_head reorder_q; /* receive reorder queue */
|
|
u32 nr_max; /* max NR. Depends on tunnel */
|
|
u32 nr_window_size; /* NR window size */
|
|
u32 nr_oos; /* NR of last OOS packet */
|
|
int nr_oos_count; /* For OOS recovery */
|
|
int nr_oos_count_max;
|
|
struct hlist_node hlist; /* Hash list node */
|
|
refcount_t ref_count;
|
|
|
|
char name[32]; /* for logging */
|
|
char ifname[IFNAMSIZ];
|
|
unsigned int data_seq:2; /* data sequencing level
|
|
* 0 => none, 1 => IP only,
|
|
* 2 => all
|
|
*/
|
|
unsigned int recv_seq:1; /* expect receive packets with
|
|
* sequence numbers? */
|
|
unsigned int send_seq:1; /* send packets with sequence
|
|
* numbers? */
|
|
unsigned int lns_mode:1; /* behave as LNS? LAC enables
|
|
* sequence numbers under
|
|
* control of LNS. */
|
|
int debug; /* bitmask of debug message
|
|
* categories */
|
|
int reorder_timeout; /* configured reorder timeout
|
|
* (in jiffies) */
|
|
int reorder_skip; /* set if skip to next nr */
|
|
int mtu;
|
|
int mru;
|
|
enum l2tp_pwtype pwtype;
|
|
struct l2tp_stats stats;
|
|
struct hlist_node global_hlist; /* Global hash list node */
|
|
|
|
int (*build_header)(struct l2tp_session *session, void *buf);
|
|
void (*recv_skb)(struct l2tp_session *session, struct sk_buff *skb, int data_len);
|
|
void (*session_close)(struct l2tp_session *session);
|
|
#if IS_ENABLED(CONFIG_L2TP_DEBUGFS)
|
|
void (*show)(struct seq_file *m, void *priv);
|
|
#endif
|
|
uint8_t priv[0]; /* private data */
|
|
};
|
|
|
|
/* Describes the tunnel. It contains info to track all the associated
|
|
* sessions so incoming packets can be sorted out
|
|
*/
|
|
struct l2tp_tunnel_cfg {
|
|
int debug; /* bitmask of debug message
|
|
* categories */
|
|
enum l2tp_encap_type encap;
|
|
|
|
/* Used only for kernel-created sockets */
|
|
struct in_addr local_ip;
|
|
struct in_addr peer_ip;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
struct in6_addr *local_ip6;
|
|
struct in6_addr *peer_ip6;
|
|
#endif
|
|
u16 local_udp_port;
|
|
u16 peer_udp_port;
|
|
unsigned int use_udp_checksums:1,
|
|
udp6_zero_tx_checksums:1,
|
|
udp6_zero_rx_checksums:1;
|
|
};
|
|
|
|
struct l2tp_tunnel {
|
|
int magic; /* Should be L2TP_TUNNEL_MAGIC */
|
|
|
|
unsigned long dead;
|
|
|
|
struct rcu_head rcu;
|
|
rwlock_t hlist_lock; /* protect session_hlist */
|
|
bool acpt_newsess; /* Indicates whether this
|
|
* tunnel accepts new sessions.
|
|
* Protected by hlist_lock.
|
|
*/
|
|
struct hlist_head session_hlist[L2TP_HASH_SIZE];
|
|
/* hashed list of sessions,
|
|
* hashed by id */
|
|
u32 tunnel_id;
|
|
u32 peer_tunnel_id;
|
|
int version; /* 2=>L2TPv2, 3=>L2TPv3 */
|
|
|
|
char name[20]; /* for logging */
|
|
int debug; /* bitmask of debug message
|
|
* categories */
|
|
enum l2tp_encap_type encap;
|
|
struct l2tp_stats stats;
|
|
|
|
struct list_head list; /* Keep a list of all tunnels */
|
|
struct net *l2tp_net; /* the net we belong to */
|
|
|
|
refcount_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 */
|
|
int fd; /* Parent fd, if tunnel socket
|
|
* was created by userspace */
|
|
|
|
struct work_struct del_work;
|
|
|
|
uint8_t priv[0]; /* private data */
|
|
};
|
|
|
|
struct l2tp_nl_cmd_ops {
|
|
int (*session_create)(struct net *net, struct l2tp_tunnel *tunnel,
|
|
u32 session_id, u32 peer_session_id,
|
|
struct l2tp_session_cfg *cfg);
|
|
int (*session_delete)(struct l2tp_session *session);
|
|
};
|
|
|
|
static inline void *l2tp_tunnel_priv(struct l2tp_tunnel *tunnel)
|
|
{
|
|
return &tunnel->priv[0];
|
|
}
|
|
|
|
static inline void *l2tp_session_priv(struct l2tp_session *session)
|
|
{
|
|
return &session->priv[0];
|
|
}
|
|
|
|
struct l2tp_tunnel *l2tp_tunnel_get(const struct net *net, u32 tunnel_id);
|
|
struct l2tp_tunnel *l2tp_tunnel_get_nth(const struct net *net, int nth);
|
|
|
|
void l2tp_tunnel_free(struct l2tp_tunnel *tunnel);
|
|
|
|
struct l2tp_session *l2tp_session_get(const struct net *net,
|
|
struct l2tp_tunnel *tunnel,
|
|
u32 session_id);
|
|
struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth);
|
|
struct l2tp_session *l2tp_session_get_by_ifname(const struct net *net,
|
|
const char *ifname);
|
|
|
|
int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id,
|
|
u32 peer_tunnel_id, struct l2tp_tunnel_cfg *cfg,
|
|
struct l2tp_tunnel **tunnelp);
|
|
int l2tp_tunnel_register(struct l2tp_tunnel *tunnel, struct net *net,
|
|
struct l2tp_tunnel_cfg *cfg);
|
|
|
|
void l2tp_tunnel_closeall(struct l2tp_tunnel *tunnel);
|
|
void l2tp_tunnel_delete(struct l2tp_tunnel *tunnel);
|
|
struct l2tp_session *l2tp_session_create(int priv_size,
|
|
struct l2tp_tunnel *tunnel,
|
|
u32 session_id, u32 peer_session_id,
|
|
struct l2tp_session_cfg *cfg);
|
|
int l2tp_session_register(struct l2tp_session *session,
|
|
struct l2tp_tunnel *tunnel);
|
|
|
|
void __l2tp_session_unhash(struct l2tp_session *session);
|
|
int l2tp_session_delete(struct l2tp_session *session);
|
|
void l2tp_session_free(struct l2tp_session *session);
|
|
void l2tp_recv_common(struct l2tp_session *session, struct sk_buff *skb,
|
|
unsigned char *ptr, unsigned char *optr, u16 hdrflags,
|
|
int length, int (*payload_hook)(struct sk_buff *skb));
|
|
int l2tp_session_queue_purge(struct l2tp_session *session);
|
|
int l2tp_udp_encap_recv(struct sock *sk, struct sk_buff *skb);
|
|
void l2tp_session_set_header_len(struct l2tp_session *session, int version);
|
|
|
|
int l2tp_xmit_skb(struct l2tp_session *session, struct sk_buff *skb,
|
|
int hdr_len);
|
|
|
|
int l2tp_nl_register_ops(enum l2tp_pwtype pw_type,
|
|
const struct l2tp_nl_cmd_ops *ops);
|
|
void l2tp_nl_unregister_ops(enum l2tp_pwtype pw_type);
|
|
int l2tp_ioctl(struct sock *sk, int cmd, unsigned long arg);
|
|
|
|
static inline void l2tp_tunnel_inc_refcount(struct l2tp_tunnel *tunnel)
|
|
{
|
|
refcount_inc(&tunnel->ref_count);
|
|
}
|
|
|
|
static inline void l2tp_tunnel_dec_refcount(struct l2tp_tunnel *tunnel)
|
|
{
|
|
if (refcount_dec_and_test(&tunnel->ref_count))
|
|
l2tp_tunnel_free(tunnel);
|
|
}
|
|
|
|
/* Session reference counts. Incremented when code obtains a reference
|
|
* to a session.
|
|
*/
|
|
static inline void l2tp_session_inc_refcount(struct l2tp_session *session)
|
|
{
|
|
refcount_inc(&session->ref_count);
|
|
}
|
|
|
|
static inline void l2tp_session_dec_refcount(struct l2tp_session *session)
|
|
{
|
|
if (refcount_dec_and_test(&session->ref_count))
|
|
l2tp_session_free(session);
|
|
}
|
|
|
|
static inline int l2tp_get_l2specific_len(struct l2tp_session *session)
|
|
{
|
|
switch (session->l2specific_type) {
|
|
case L2TP_L2SPECTYPE_DEFAULT:
|
|
return 4;
|
|
case L2TP_L2SPECTYPE_NONE:
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
#define l2tp_printk(ptr, type, func, fmt, ...) \
|
|
do { \
|
|
if (((ptr)->debug) & (type)) \
|
|
func(fmt, ##__VA_ARGS__); \
|
|
} while (0)
|
|
|
|
#define l2tp_warn(ptr, type, fmt, ...) \
|
|
l2tp_printk(ptr, type, pr_warn, fmt, ##__VA_ARGS__)
|
|
#define l2tp_info(ptr, type, fmt, ...) \
|
|
l2tp_printk(ptr, type, pr_info, fmt, ##__VA_ARGS__)
|
|
#define l2tp_dbg(ptr, type, fmt, ...) \
|
|
l2tp_printk(ptr, type, pr_debug, fmt, ##__VA_ARGS__)
|
|
|
|
#define MODULE_ALIAS_L2TP_PWTYPE(type) \
|
|
MODULE_ALIAS("net-l2tp-type-" __stringify(type))
|
|
|
|
#endif /* _L2TP_CORE_H_ */
|