ax25.h

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/*
 *  Declarations of AX.25 type objects.
 *
 *  Alan Cox (GW4PTS)   10/11/93
 */
#ifndef _AX25_H
#define _AX25_H 

#include <linux/ax25.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/atomic.h>

#define AX25_T1CLAMPLO          1
#define AX25_T1CLAMPHI          (30 * HZ)

#define AX25_BPQ_HEADER_LEN     16
#define AX25_KISS_HEADER_LEN        1

#define AX25_HEADER_LEN         17
#define AX25_ADDR_LEN           7
#define AX25_DIGI_HEADER_LEN        (AX25_MAX_DIGIS * AX25_ADDR_LEN)
#define AX25_MAX_HEADER_LEN     (AX25_HEADER_LEN + AX25_DIGI_HEADER_LEN)

/* AX.25 Protocol IDs */
#define AX25_P_ROSE         0x01
#define AX25_P_VJCOMP           0x06    /* Compressed TCP/IP packet   */
                        /* Van Jacobsen (RFC 1144)    */
#define AX25_P_VJUNCOMP         0x07    /* Uncompressed TCP/IP packet */
                        /* Van Jacobsen (RFC 1144)    */
#define AX25_P_SEGMENT          0x08    /* Segmentation fragment      */
#define AX25_P_TEXNET           0xc3    /* TEXTNET datagram protocol  */
#define AX25_P_LQ           0xc4    /* Link Quality Protocol      */
#define AX25_P_ATALK            0xca    /* Appletalk                  */
#define AX25_P_ATALK_ARP        0xcb    /* Appletalk ARP              */
#define AX25_P_IP           0xcc    /* ARPA Internet Protocol     */
#define AX25_P_ARP          0xcd    /* ARPA Address Resolution    */
#define AX25_P_FLEXNET          0xce    /* FlexNet                    */
#define AX25_P_NETROM           0xcf    /* NET/ROM                    */
#define AX25_P_TEXT             0xF0    /* No layer 3 protocol impl.  */

/* AX.25 Segment control values */
#define AX25_SEG_REM            0x7F
#define AX25_SEG_FIRST          0x80

#define AX25_CBIT           0x80    /* Command/Response bit */
#define AX25_EBIT           0x01    /* HDLC Address Extension bit */
#define AX25_HBIT           0x80    /* Has been repeated bit */

#define AX25_SSSID_SPARE        0x60    /* Unused bits in SSID for standard AX.25 */
#define AX25_ESSID_SPARE        0x20    /* Unused bits in SSID for extended AX.25 */
#define AX25_DAMA_FLAG          0x20    /* Well, it is *NOT* unused! (dl1bke 951121 */

#define AX25_COND_ACK_PENDING       0x01
#define AX25_COND_REJECT        0x02
#define AX25_COND_PEER_RX_BUSY      0x04
#define AX25_COND_OWN_RX_BUSY       0x08
#define AX25_COND_DAMA_MODE     0x10

#ifndef _LINUX_NETDEVICE_H
#include <linux/netdevice.h>
#endif

/* Upper sub-layer (LAPB) definitions */

/* Control field templates */
#define AX25_I          0x00    /* Information frames */
#define AX25_S          0x01    /* Supervisory frames */
#define AX25_RR         0x01    /* Receiver ready */
#define AX25_RNR        0x05    /* Receiver not ready */
#define AX25_REJ        0x09    /* Reject */
#define AX25_U          0x03    /* Unnumbered frames */
#define AX25_SABM       0x2f    /* Set Asynchronous Balanced Mode */
#define AX25_SABME      0x6f    /* Set Asynchronous Balanced Mode Extended */
#define AX25_DISC       0x43    /* Disconnect */
#define AX25_DM         0x0f    /* Disconnected mode */
#define AX25_UA         0x63    /* Unnumbered acknowledge */
#define AX25_FRMR       0x87    /* Frame reject */
#define AX25_UI         0x03    /* Unnumbered information */
#define AX25_XID        0xaf    /* Exchange information */
#define AX25_TEST       0xe3    /* Test */

#define AX25_PF         0x10    /* Poll/final bit for standard AX.25 */
#define AX25_EPF        0x01    /* Poll/final bit for extended AX.25 */

#define AX25_ILLEGAL        0x100   /* Impossible to be a real frame type */

#define AX25_POLLOFF        0
#define AX25_POLLON     1

/* AX25 L2 C-bit */
#define AX25_COMMAND        1
#define AX25_RESPONSE       2

/* Define Link State constants. */

enum { 
    AX25_STATE_0,           /* Listening */
    AX25_STATE_1,           /* SABM sent */
    AX25_STATE_2,           /* DISC sent */
    AX25_STATE_3,           /* Established */
    AX25_STATE_4            /* Recovery */
};

#define AX25_MODULUS        8   /*  Standard AX.25 modulus */
#define AX25_EMODULUS       128 /*  Extended AX.25 modulus */

enum {
    AX25_PROTO_STD_SIMPLEX,
    AX25_PROTO_STD_DUPLEX,
#ifdef CONFIG_AX25_DAMA_SLAVE
    AX25_PROTO_DAMA_SLAVE,
#ifdef CONFIG_AX25_DAMA_MASTER
    AX25_PROTO_DAMA_MASTER,
#define AX25_PROTO_MAX AX25_PROTO_DAMA_MASTER
#endif
#endif
    __AX25_PROTO_MAX,
    AX25_PROTO_MAX = __AX25_PROTO_MAX -1
};

enum {
    AX25_VALUES_IPDEFMODE,  /* 0=DG 1=VC */
    AX25_VALUES_AXDEFMODE,  /* 0=Normal 1=Extended Seq Nos */
    AX25_VALUES_BACKOFF,    /* 0=None 1=Linear 2=Exponential */
    AX25_VALUES_CONMODE,    /* Allow connected modes - 0=No 1=no "PID text" 2=all PIDs */
    AX25_VALUES_WINDOW, /* Default window size for standard AX.25 */
    AX25_VALUES_EWINDOW,    /* Default window size for extended AX.25 */
    AX25_VALUES_T1,     /* Default T1 timeout value */
    AX25_VALUES_T2,     /* Default T2 timeout value */
    AX25_VALUES_T3,     /* Default T3 timeout value */
    AX25_VALUES_IDLE,   /* Connected mode idle timer */
    AX25_VALUES_N2,     /* Default N2 value */
    AX25_VALUES_PACLEN, /* AX.25 MTU */
    AX25_VALUES_PROTOCOL,   /* Std AX.25, DAMA Slave, DAMA Master */
    AX25_VALUES_DS_TIMEOUT, /* DAMA Slave timeout */
    AX25_MAX_VALUES     /* THIS MUST REMAIN THE LAST ENTRY OF THIS LIST */
};

#define AX25_DEF_IPDEFMODE  0           /* Datagram */
#define AX25_DEF_AXDEFMODE  0           /* Normal */
#define AX25_DEF_BACKOFF    1           /* Linear backoff */
#define AX25_DEF_CONMODE    2           /* Connected mode allowed */
#define AX25_DEF_WINDOW     2           /* Window=2 */
#define AX25_DEF_EWINDOW    32          /* Module-128 Window=32 */
#define AX25_DEF_T1     10000           /* T1=10s */
#define AX25_DEF_T2     3000            /* T2=3s  */
#define AX25_DEF_T3     300000          /* T3=300s */
#define AX25_DEF_N2     10          /* N2=10 */
#define AX25_DEF_IDLE       0           /* Idle=None */
#define AX25_DEF_PACLEN     256         /* Paclen=256 */
#define AX25_DEF_PROTOCOL   AX25_PROTO_STD_SIMPLEX  /* Standard AX.25 */
#define AX25_DEF_DS_TIMEOUT 180000          /* DAMA timeout 3 minutes */

typedef struct ax25_uid_assoc {
    struct hlist_node   uid_node;
    atomic_t        refcount;
    kuid_t          uid;
    ax25_address        call;
} ax25_uid_assoc;

#define ax25_uid_for_each(__ax25, node, list) \
    hlist_for_each_entry(__ax25, node, list, uid_node)

#define ax25_uid_hold(ax25) \
    atomic_inc(&((ax25)->refcount))

static inline void ax25_uid_put(ax25_uid_assoc *assoc)
{
    if (atomic_dec_and_test(&assoc->refcount)) {
        kfree(assoc);
    }
}

typedef struct {
    ax25_address        calls[AX25_MAX_DIGIS];
    unsigned char       repeated[AX25_MAX_DIGIS];
    unsigned char       ndigi;
    signed char     lastrepeat;
} ax25_digi;

typedef struct ax25_route {
    struct ax25_route   *next;
    atomic_t        refcount;
    ax25_address        callsign;
    struct net_device   *dev;
    ax25_digi       *digipeat;
    char            ip_mode;
} ax25_route;

static inline void ax25_hold_route(ax25_route *ax25_rt)
{
    atomic_inc(&ax25_rt->refcount);
}

extern void __ax25_put_route(ax25_route *ax25_rt);

static inline void ax25_put_route(ax25_route *ax25_rt)
{
    if (atomic_dec_and_test(&ax25_rt->refcount))
        __ax25_put_route(ax25_rt);
}

typedef struct {
    char            slave;          /* slave_mode?   */
    struct timer_list   slave_timer;        /* timeout timer */
    unsigned short      slave_timeout;      /* when? */
} ax25_dama_info;

struct ctl_table;

typedef struct ax25_dev {
    struct ax25_dev     *next;
    struct net_device   *dev;
    struct net_device   *forward;
    struct ctl_table_header *sysheader;
    int         values[AX25_MAX_VALUES];
#if defined(CONFIG_AX25_DAMA_SLAVE) || defined(CONFIG_AX25_DAMA_MASTER)
    ax25_dama_info      dama;
#endif
} ax25_dev;

typedef struct ax25_cb {
    struct hlist_node   ax25_node;
    ax25_address        source_addr, dest_addr;
    ax25_digi       *digipeat;
    ax25_dev        *ax25_dev;
    unsigned char       iamdigi;
    unsigned char       state, modulus, pidincl;
    unsigned short      vs, vr, va;
    unsigned char       condition, backoff;
    unsigned char       n2, n2count;
    struct timer_list   t1timer, t2timer, t3timer, idletimer;
    unsigned long       t1, t2, t3, idle, rtt;
    unsigned short      paclen, fragno, fraglen;
    struct sk_buff_head write_queue;
    struct sk_buff_head reseq_queue;
    struct sk_buff_head ack_queue;
    struct sk_buff_head frag_queue;
    unsigned char       window;
    struct timer_list   timer, dtimer;
    struct sock     *sk;        /* Backlink to socket */
    atomic_t        refcount;
} ax25_cb;

#define ax25_sk(__sk) ((ax25_cb *)(__sk)->sk_protinfo)

#define ax25_for_each(__ax25, node, list) \
    hlist_for_each_entry(__ax25, node, list, ax25_node)

#define ax25_cb_hold(__ax25) \
    atomic_inc(&((__ax25)->refcount))

static __inline__ void ax25_cb_put(ax25_cb *ax25)
{
    if (atomic_dec_and_test(&ax25->refcount)) {
        kfree(ax25->digipeat);
        kfree(ax25);
    }
}

static inline __be16 ax25_type_trans(struct sk_buff *skb, struct net_device *dev)
{
    skb->dev      = dev;
    skb_reset_mac_header(skb);
    skb->pkt_type = PACKET_HOST;
    return htons(ETH_P_AX25);
}

/* af_ax25.c */
extern struct hlist_head ax25_list;
extern spinlock_t ax25_list_lock;
extern void ax25_cb_add(ax25_cb *);
struct sock *ax25_find_listener(ax25_address *, int, struct net_device *, int);
struct sock *ax25_get_socket(ax25_address *, ax25_address *, int);
extern ax25_cb *ax25_find_cb(ax25_address *, ax25_address *, ax25_digi *, struct net_device *);
extern void ax25_send_to_raw(ax25_address *, struct sk_buff *, int);
extern void ax25_destroy_socket(ax25_cb *);
extern ax25_cb * __must_check ax25_create_cb(void);
extern void ax25_fillin_cb(ax25_cb *, ax25_dev *);
extern struct sock *ax25_make_new(struct sock *, struct ax25_dev *);

/* ax25_addr.c */
extern const ax25_address ax25_bcast;
extern const ax25_address ax25_defaddr;
extern const ax25_address null_ax25_address;
extern char *ax2asc(char *buf, const ax25_address *);
extern void asc2ax(ax25_address *addr, const char *callsign);
extern int ax25cmp(const ax25_address *, const ax25_address *);
extern int ax25digicmp(const ax25_digi *, const ax25_digi *);
extern const unsigned char *ax25_addr_parse(const unsigned char *, int,
    ax25_address *, ax25_address *, ax25_digi *, int *, int *);
extern int  ax25_addr_build(unsigned char *, const ax25_address *,
    const ax25_address *, const ax25_digi *, int, int);
extern int  ax25_addr_size(const ax25_digi *);
extern void ax25_digi_invert(const ax25_digi *, ax25_digi *);

/* ax25_dev.c */
extern ax25_dev *ax25_dev_list;
extern spinlock_t ax25_dev_lock;

static inline ax25_dev *ax25_dev_ax25dev(struct net_device *dev)
{
    return dev->ax25_ptr;
}

extern ax25_dev *ax25_addr_ax25dev(ax25_address *);
extern void ax25_dev_device_up(struct net_device *);
extern void ax25_dev_device_down(struct net_device *);
extern int  ax25_fwd_ioctl(unsigned int, struct ax25_fwd_struct *);
extern struct net_device *ax25_fwd_dev(struct net_device *);
extern void ax25_dev_free(void);

/* ax25_ds_in.c */
extern int  ax25_ds_frame_in(ax25_cb *, struct sk_buff *, int);

/* ax25_ds_subr.c */
extern void ax25_ds_nr_error_recovery(ax25_cb *);
extern void ax25_ds_enquiry_response(ax25_cb *);
extern void ax25_ds_establish_data_link(ax25_cb *);
extern void ax25_dev_dama_off(ax25_dev *);
extern void ax25_dama_on(ax25_cb *);
extern void ax25_dama_off(ax25_cb *);

/* ax25_ds_timer.c */
extern void ax25_ds_setup_timer(ax25_dev *);
extern void ax25_ds_set_timer(ax25_dev *);
extern void ax25_ds_del_timer(ax25_dev *);
extern void ax25_ds_timer(ax25_cb *);
extern void ax25_ds_t1_timeout(ax25_cb *);
extern void ax25_ds_heartbeat_expiry(ax25_cb *);
extern void ax25_ds_t3timer_expiry(ax25_cb *);
extern void ax25_ds_idletimer_expiry(ax25_cb *);

/* ax25_iface.c */

struct ax25_protocol {
    struct ax25_protocol *next;
    unsigned int pid;
    int (*func)(struct sk_buff *, ax25_cb *);
};

extern void ax25_register_pid(struct ax25_protocol *ap);
extern void ax25_protocol_release(unsigned int);

struct ax25_linkfail {
    struct hlist_node lf_node;
    void (*func)(ax25_cb *, int);
};

extern void ax25_linkfail_register(struct ax25_linkfail *lf);
extern void ax25_linkfail_release(struct ax25_linkfail *lf);
extern int __must_check ax25_listen_register(ax25_address *,
    struct net_device *);
extern void ax25_listen_release(ax25_address *, struct net_device *);
extern int  (*ax25_protocol_function(unsigned int))(struct sk_buff *, ax25_cb *);
extern int  ax25_listen_mine(ax25_address *, struct net_device *);
extern void ax25_link_failed(ax25_cb *, int);
extern int  ax25_protocol_is_registered(unsigned int);

/* ax25_in.c */
extern int  ax25_rx_iframe(ax25_cb *, struct sk_buff *);
extern int  ax25_kiss_rcv(struct sk_buff *, struct net_device *, struct packet_type *, struct net_device *);

/* ax25_ip.c */
extern int ax25_hard_header(struct sk_buff *, struct net_device *,
                unsigned short, const void *,
                const void *, unsigned int);
extern int  ax25_rebuild_header(struct sk_buff *);
extern const struct header_ops ax25_header_ops;

/* ax25_out.c */
extern ax25_cb *ax25_send_frame(struct sk_buff *, int, ax25_address *, ax25_address *, ax25_digi *, struct net_device *);
extern void ax25_output(ax25_cb *, int, struct sk_buff *);
extern void ax25_kick(ax25_cb *);
extern void ax25_transmit_buffer(ax25_cb *, struct sk_buff *, int);
extern void ax25_queue_xmit(struct sk_buff *skb, struct net_device *dev);
extern int  ax25_check_iframes_acked(ax25_cb *, unsigned short);

/* ax25_route.c */
extern void ax25_rt_device_down(struct net_device *);
extern int  ax25_rt_ioctl(unsigned int, void __user *);
extern const struct file_operations ax25_route_fops;
extern ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev);
extern int  ax25_rt_autobind(ax25_cb *, ax25_address *);
extern struct sk_buff *ax25_rt_build_path(struct sk_buff *, ax25_address *, ax25_address *, ax25_digi *);
extern void ax25_rt_free(void);

/* ax25_std_in.c */
extern int  ax25_std_frame_in(ax25_cb *, struct sk_buff *, int);

/* ax25_std_subr.c */
extern void ax25_std_nr_error_recovery(ax25_cb *);
extern void ax25_std_establish_data_link(ax25_cb *);
extern void ax25_std_transmit_enquiry(ax25_cb *);
extern void ax25_std_enquiry_response(ax25_cb *);
extern void ax25_std_timeout_response(ax25_cb *);

/* ax25_std_timer.c */
extern void ax25_std_heartbeat_expiry(ax25_cb *);
extern void ax25_std_t1timer_expiry(ax25_cb *);
extern void ax25_std_t2timer_expiry(ax25_cb *);
extern void ax25_std_t3timer_expiry(ax25_cb *);
extern void ax25_std_idletimer_expiry(ax25_cb *);

/* ax25_subr.c */
extern void ax25_clear_queues(ax25_cb *);
extern void ax25_frames_acked(ax25_cb *, unsigned short);
extern void ax25_requeue_frames(ax25_cb *);
extern int  ax25_validate_nr(ax25_cb *, unsigned short);
extern int  ax25_decode(ax25_cb *, struct sk_buff *, int *, int *, int *);
extern void ax25_send_control(ax25_cb *, int, int, int);
extern void ax25_return_dm(struct net_device *, ax25_address *, ax25_address *, ax25_digi *);
extern void ax25_calculate_t1(ax25_cb *);
extern void ax25_calculate_rtt(ax25_cb *);
extern void ax25_disconnect(ax25_cb *, int);

/* ax25_timer.c */
extern void ax25_setup_timers(ax25_cb *);
extern void ax25_start_heartbeat(ax25_cb *);
extern void ax25_start_t1timer(ax25_cb *);
extern void ax25_start_t2timer(ax25_cb *);
extern void ax25_start_t3timer(ax25_cb *);
extern void ax25_start_idletimer(ax25_cb *);
extern void ax25_stop_heartbeat(ax25_cb *);
extern void ax25_stop_t1timer(ax25_cb *);
extern void ax25_stop_t2timer(ax25_cb *);
extern void ax25_stop_t3timer(ax25_cb *);
extern void ax25_stop_idletimer(ax25_cb *);
extern int  ax25_t1timer_running(ax25_cb *);
extern unsigned long ax25_display_timer(struct timer_list *);

/* ax25_uid.c */
extern int  ax25_uid_policy;
extern ax25_uid_assoc *ax25_findbyuid(kuid_t);
extern int __must_check ax25_uid_ioctl(int, struct sockaddr_ax25 *);
extern const struct file_operations ax25_uid_fops;
extern void ax25_uid_free(void);

/* sysctl_net_ax25.c */
#ifdef CONFIG_SYSCTL
extern int ax25_register_dev_sysctl(ax25_dev *ax25_dev);
extern void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev);
#else
static inline int ax25_register_dev_sysctl(ax25_dev *ax25_dev) { return 0; }
static inline void ax25_unregister_dev_sysctl(ax25_dev *ax25_dev) {}
#endif /* CONFIG_SYSCTL */

#endif