linux/include/net/x25.h
Shaun Pereira ebc3f64b86 [X25]: Fast select with no restriction on response
This patch is a follow up to patch 1 regarding "Selective Sub Address
matching with call user data".  It allows use of the Fast-Select-Acceptance
optional user facility for X.25.

This patch just implements fast select with no restriction on response
(NRR).  What this means (according to ITU-T Recomendation 10/96 section
6.16) is that if in an incoming call packet, the relevant facility bits are
set for fast-select-NRR, then the called DTE can issue a direct response to
the incoming packet using a call-accepted packet that contains
call-user-data.  This patch allows such a response.  

The called DTE can also respond with a clear-request packet that contains
call-user-data.  However, this feature is currently not implemented by the
patch.

How is Fast Select Acceptance used?
By default, the system does not allow fast select acceptance (as before).
To enable a response to fast select acceptance,  
After a listen socket in created and bound as follows
	socket(AF_X25, SOCK_SEQPACKET, 0);
	bind(call_soc, (struct sockaddr *)&locl_addr, sizeof(locl_addr));
but before a listen system call is made, the following ioctl should be used.
	ioctl(call_soc,SIOCX25CALLACCPTAPPRV);
Now the listen system call can be made
	listen(call_soc, 4);
After this, an incoming-call packet will be accepted, but no call-accepted 
packet will be sent back until the following system call is made on the socket
that accepts the call
	ioctl(vc_soc,SIOCX25SENDCALLACCPT);
The network (or cisco xot router used for testing here) will allow the 
application server's call-user-data in the call-accepted packet, 
provided the call-request was made with Fast-select NRR.

Signed-off-by: Shaun Pereira <spereira@tusc.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:16:17 -07:00

275 lines
8.3 KiB
C

/*
* Declarations of X.25 Packet Layer type objects.
*
* History
* nov/17/96 Jonathan Naylor Initial version.
* mar/20/00 Daniela Squassoni Disabling/enabling of facilities
* negotiation.
*/
#ifndef _X25_H
#define _X25_H
#include <linux/x25.h>
#include <net/sock.h>
#define X25_ADDR_LEN 16
#define X25_MAX_L2_LEN 18 /* 802.2 LLC */
#define X25_STD_MIN_LEN 3
#define X25_EXT_MIN_LEN 4
#define X25_GFI_SEQ_MASK 0x30
#define X25_GFI_STDSEQ 0x10
#define X25_GFI_EXTSEQ 0x20
#define X25_Q_BIT 0x80
#define X25_D_BIT 0x40
#define X25_STD_M_BIT 0x10
#define X25_EXT_M_BIT 0x01
#define X25_CALL_REQUEST 0x0B
#define X25_CALL_ACCEPTED 0x0F
#define X25_CLEAR_REQUEST 0x13
#define X25_CLEAR_CONFIRMATION 0x17
#define X25_DATA 0x00
#define X25_INTERRUPT 0x23
#define X25_INTERRUPT_CONFIRMATION 0x27
#define X25_RR 0x01
#define X25_RNR 0x05
#define X25_REJ 0x09
#define X25_RESET_REQUEST 0x1B
#define X25_RESET_CONFIRMATION 0x1F
#define X25_REGISTRATION_REQUEST 0xF3
#define X25_REGISTRATION_CONFIRMATION 0xF7
#define X25_RESTART_REQUEST 0xFB
#define X25_RESTART_CONFIRMATION 0xFF
#define X25_DIAGNOSTIC 0xF1
#define X25_ILLEGAL 0xFD
/* Define the various conditions that may exist */
#define X25_COND_ACK_PENDING 0x01
#define X25_COND_OWN_RX_BUSY 0x02
#define X25_COND_PEER_RX_BUSY 0x04
/* Define Link State constants. */
enum {
X25_STATE_0, /* Ready */
X25_STATE_1, /* Awaiting Call Accepted */
X25_STATE_2, /* Awaiting Clear Confirmation */
X25_STATE_3, /* Data Transfer */
X25_STATE_4 /* Awaiting Reset Confirmation */
};
enum {
X25_LINK_STATE_0,
X25_LINK_STATE_1,
X25_LINK_STATE_2,
X25_LINK_STATE_3
};
#define X25_DEFAULT_T20 (180 * HZ) /* Default T20 value */
#define X25_DEFAULT_T21 (200 * HZ) /* Default T21 value */
#define X25_DEFAULT_T22 (180 * HZ) /* Default T22 value */
#define X25_DEFAULT_T23 (180 * HZ) /* Default T23 value */
#define X25_DEFAULT_T2 (3 * HZ) /* Default ack holdback value */
#define X25_DEFAULT_WINDOW_SIZE 2 /* Default Window Size */
#define X25_DEFAULT_PACKET_SIZE X25_PS128 /* Default Packet Size */
#define X25_DEFAULT_THROUGHPUT 0x0A /* Deafult Throughput */
#define X25_DEFAULT_REVERSE 0x00 /* Default Reverse Charging */
#define X25_DENY_ACCPT_APPRV 0x01 /* Default value */
#define X25_ALLOW_ACCPT_APPRV 0x00 /* Control enabled */
#define X25_SMODULUS 8
#define X25_EMODULUS 128
/*
* X.25 Facilities constants.
*/
#define X25_FAC_CLASS_MASK 0xC0
#define X25_FAC_CLASS_A 0x00
#define X25_FAC_CLASS_B 0x40
#define X25_FAC_CLASS_C 0x80
#define X25_FAC_CLASS_D 0xC0
#define X25_FAC_REVERSE 0x01 /* also fast select */
#define X25_FAC_THROUGHPUT 0x02
#define X25_FAC_PACKET_SIZE 0x42
#define X25_FAC_WINDOW_SIZE 0x43
#define X25_MAX_FAC_LEN 20 /* Plenty to spare */
#define X25_MAX_CUD_LEN 128
/**
* struct x25_route - x25 routing entry
* @node - entry in x25_list_lock
* @address - Start of address range
* @sigdigits - Number of sig digits
* @dev - More than one for MLP
* @refcnt - reference counter
*/
struct x25_route {
struct list_head node;
struct x25_address address;
unsigned int sigdigits;
struct net_device *dev;
atomic_t refcnt;
};
struct x25_neigh {
struct list_head node;
struct net_device *dev;
unsigned int state;
unsigned int extended;
struct sk_buff_head queue;
unsigned long t20;
struct timer_list t20timer;
unsigned long global_facil_mask;
atomic_t refcnt;
};
struct x25_sock {
struct sock sk;
struct x25_address source_addr, dest_addr;
struct x25_neigh *neighbour;
unsigned int lci, cudmatchlength;
unsigned char state, condition, qbitincl, intflag, accptapprv;
unsigned short vs, vr, va, vl;
unsigned long t2, t21, t22, t23;
unsigned short fraglen;
struct sk_buff_head ack_queue;
struct sk_buff_head fragment_queue;
struct sk_buff_head interrupt_in_queue;
struct sk_buff_head interrupt_out_queue;
struct timer_list timer;
struct x25_causediag causediag;
struct x25_facilities facilities;
struct x25_calluserdata calluserdata;
unsigned long vc_facil_mask; /* inc_call facilities mask */
};
static inline struct x25_sock *x25_sk(const struct sock *sk)
{
return (struct x25_sock *)sk;
}
/* af_x25.c */
extern int sysctl_x25_restart_request_timeout;
extern int sysctl_x25_call_request_timeout;
extern int sysctl_x25_reset_request_timeout;
extern int sysctl_x25_clear_request_timeout;
extern int sysctl_x25_ack_holdback_timeout;
extern int x25_addr_ntoa(unsigned char *, struct x25_address *,
struct x25_address *);
extern int x25_addr_aton(unsigned char *, struct x25_address *,
struct x25_address *);
extern struct sock *x25_find_socket(unsigned int, struct x25_neigh *);
extern void x25_destroy_socket(struct sock *);
extern int x25_rx_call_request(struct sk_buff *, struct x25_neigh *, unsigned int);
extern void x25_kill_by_neigh(struct x25_neigh *);
/* x25_dev.c */
extern void x25_send_frame(struct sk_buff *, struct x25_neigh *);
extern int x25_lapb_receive_frame(struct sk_buff *, struct net_device *, struct packet_type *);
extern void x25_establish_link(struct x25_neigh *);
extern void x25_terminate_link(struct x25_neigh *);
/* x25_facilities.c */
extern int x25_parse_facilities(struct sk_buff *, struct x25_facilities *, unsigned long *);
extern int x25_create_facilities(unsigned char *, struct x25_facilities *, unsigned long);
extern int x25_negotiate_facilities(struct sk_buff *, struct sock *, struct x25_facilities *);
extern void x25_limit_facilities(struct x25_facilities *, struct x25_neigh *);
/* x25_in.c */
extern int x25_process_rx_frame(struct sock *, struct sk_buff *);
extern int x25_backlog_rcv(struct sock *, struct sk_buff *);
/* x25_link.c */
extern void x25_link_control(struct sk_buff *, struct x25_neigh *, unsigned short);
extern void x25_link_device_up(struct net_device *);
extern void x25_link_device_down(struct net_device *);
extern void x25_link_established(struct x25_neigh *);
extern void x25_link_terminated(struct x25_neigh *);
extern void x25_transmit_clear_request(struct x25_neigh *, unsigned int, unsigned char);
extern void x25_transmit_link(struct sk_buff *, struct x25_neigh *);
extern int x25_subscr_ioctl(unsigned int, void __user *);
extern struct x25_neigh *x25_get_neigh(struct net_device *);
extern void x25_link_free(void);
/* x25_neigh.c */
static __inline__ void x25_neigh_hold(struct x25_neigh *nb)
{
atomic_inc(&nb->refcnt);
}
static __inline__ void x25_neigh_put(struct x25_neigh *nb)
{
if (atomic_dec_and_test(&nb->refcnt))
kfree(nb);
}
/* x25_out.c */
extern int x25_output(struct sock *, struct sk_buff *);
extern void x25_kick(struct sock *);
extern void x25_enquiry_response(struct sock *);
/* x25_route.c */
extern struct x25_route *x25_get_route(struct x25_address *addr);
extern struct net_device *x25_dev_get(char *);
extern void x25_route_device_down(struct net_device *dev);
extern int x25_route_ioctl(unsigned int, void __user *);
extern void x25_route_free(void);
static __inline__ void x25_route_hold(struct x25_route *rt)
{
atomic_inc(&rt->refcnt);
}
static __inline__ void x25_route_put(struct x25_route *rt)
{
if (atomic_dec_and_test(&rt->refcnt))
kfree(rt);
}
/* x25_subr.c */
extern void x25_clear_queues(struct sock *);
extern void x25_frames_acked(struct sock *, unsigned short);
extern void x25_requeue_frames(struct sock *);
extern int x25_validate_nr(struct sock *, unsigned short);
extern void x25_write_internal(struct sock *, int);
extern int x25_decode(struct sock *, struct sk_buff *, int *, int *, int *, int *, int *);
extern void x25_disconnect(struct sock *, int, unsigned char, unsigned char);
/* x25_timer.c */
extern void x25_start_heartbeat(struct sock *);
extern void x25_start_t2timer(struct sock *);
extern void x25_start_t21timer(struct sock *);
extern void x25_start_t22timer(struct sock *);
extern void x25_start_t23timer(struct sock *);
extern void x25_stop_heartbeat(struct sock *);
extern void x25_stop_timer(struct sock *);
extern unsigned long x25_display_timer(struct sock *);
extern void x25_check_rbuf(struct sock *);
/* sysctl_net_x25.c */
extern void x25_register_sysctl(void);
extern void x25_unregister_sysctl(void);
struct x25_skb_cb {
unsigned flags;
};
#define X25_SKB_CB(s) ((struct x25_skb_cb *) ((s)->cb))
extern struct hlist_head x25_list;
extern rwlock_t x25_list_lock;
extern struct list_head x25_route_list;
extern rwlock_t x25_route_list_lock;
extern int x25_proc_init(void);
extern void x25_proc_exit(void);
#endif