include/linux/isdn_ppp.h

   1 /* Linux ISDN subsystem, sync PPP, interface to ipppd
   2  *
   3  * Copyright 1994-1999  by Fritz Elfert (fritz@isdn4linux.de)
   4  * Copyright 1995,96    Thinking Objects Software GmbH Wuerzburg
   5  * Copyright 1995,96    by Michael Hipp (Michael.Hipp@student.uni-tuebingen.de)
   6  * Copyright 2000-2002  by Kai Germaschewski (kai@germaschewski.name)
   7  *
   8  * This software may be used and distributed according to the terms
   9  * of the GNU General Public License, incorporated herein by reference.
  10  *
  11  */
  12 #ifndef _LINUX_ISDN_PPP_H
  13 #define _LINUX_ISDN_PPP_H
  14
  15
  16
  17
  18 #ifdef CONFIG_IPPP_FILTER
  19 #include <linux/filter.h>
  20 #endif
  21 #include <uapi/linux/isdn_ppp.h>
  22
  23 #define DECOMP_ERR_NOMEM        (-10)
  24
  25 #define MP_END_FRAG    0x40
  26 #define MP_BEGIN_FRAG  0x80
  27
  28 #define MP_MAX_QUEUE_LEN        16
  29
  30 /*
  31  * We need a way for the decompressor to influence the generation of CCP
  32  * Reset-Requests in a variety of ways. The decompressor is already returning
  33  * a lot of information (generated skb length, error conditions) so we use
  34  * another parameter. This parameter is a pointer to a structure which is
  35  * to be marked valid by the decompressor and only in this case is ever used.
  36  * Furthermore, the only case where this data is used is when the decom-
  37  * pressor returns DECOMP_ERROR.
  38  *
  39  * We use this same struct for the reset entry of the compressor to commu-
  40  * nicate to its caller how to deal with sending of a Reset Ack. In this
  41  * case, expra is not used, but other options still apply (suppressing
  42  * sending with rsend, appending arbitrary data, etc).
  43  */
  44
  45 #define IPPP_RESET_MAXDATABYTES 32
  46
  47 struct isdn_ppp_resetparams {
  48   unsigned char valid:1;        /* rw Is this structure filled at all ? */
  49   unsigned char rsend:1;        /* rw Should we send one at all ? */
  50   unsigned char idval:1;        /* rw Is the id field valid ? */
  51   unsigned char dtval:1;        /* rw Is the data field valid ? */
  52   unsigned char expra:1;        /* rw Is an Ack expected for this Req ? */
  53   unsigned char id;             /* wo Send CCP ResetReq with this id */
  54   unsigned short maxdlen;       /* ro Max bytes to be stored in data field */
  55   unsigned short dlen;          /* rw Bytes stored in data field */
  56   unsigned char *data;          /* wo Data for ResetReq info field */
  57 };
  58
  59 /*
  60  * this is an 'old friend' from ppp-comp.h under a new name
  61  * check the original include for more information
  62  */
  63 struct isdn_ppp_compressor {
  64   struct isdn_ppp_compressor *next, *prev;
  65   struct module *owner;
  66   int num; /* CCP compression protocol number */
  67
  68   void *(*alloc) (struct isdn_ppp_comp_data *);
  69   void (*free) (void *state);
  70   int  (*init) (void *state, struct isdn_ppp_comp_data *,
  71                 int unit,int debug);
  72
  73   /* The reset entry needs to get more exact information about the
  74      ResetReq or ResetAck it was called with. The parameters are
  75      obvious. If reset is called without a Req or Ack frame which
  76      could be handed into it, code MUST be set to 0. Using rsparm,
  77      the reset entry can control if and how a ResetAck is returned. */
  78
  79   void (*reset) (void *state, unsigned char code, unsigned char id,
  80                  unsigned char *data, unsigned len,
  81                  struct isdn_ppp_resetparams *rsparm);
  82
  83   int  (*compress) (void *state, struct sk_buff *in,
  84                     struct sk_buff *skb_out, int proto);
  85
  86         int  (*decompress) (void *state,struct sk_buff *in,
  87                             struct sk_buff *skb_out,
  88                             struct isdn_ppp_resetparams *rsparm);
  89
  90   void (*incomp) (void *state, struct sk_buff *in,int proto);
  91   void (*stat) (void *state, struct compstat *stats);
  92 };
  93
  94 extern int isdn_ppp_register_compressor(struct isdn_ppp_compressor *);
  95 extern int isdn_ppp_unregister_compressor(struct isdn_ppp_compressor *);
  96 extern int isdn_ppp_dial_slave(char *);
  97 extern int isdn_ppp_hangup_slave(char *);
  98
  99 typedef struct {
 100   unsigned long seqerrs;
 101   unsigned long frame_drops;
 102   unsigned long overflows;
 103   unsigned long max_queue_len;
 104 } isdn_mppp_stats;
 105
 106 typedef struct {
 107   int mp_mrru;                        /* unused                             */
 108   struct sk_buff * frags;       /* fragments sl list -- use skb->next */
 109   long frames;                  /* number of frames in the frame list */
 110   unsigned int seq;             /* last processed packet seq #: any packets
 111                                  * with smaller seq # will be dropped
 112                                  * unconditionally */
 113   spinlock_t lock;
 114   int ref_ct;
 115   /* statistics */
 116   isdn_mppp_stats stats;
 117 } ippp_bundle;
 118
 119 #define NUM_RCV_BUFFS     64
 120
 121 struct ippp_buf_queue {
 122   struct ippp_buf_queue *next;
 123   struct ippp_buf_queue *last;
 124   char *buf;                 /* NULL here indicates end of queue */
 125   int len;
 126 };
 127
 128 /* The data structure for one CCP reset transaction */
 129 enum ippp_ccp_reset_states {
 130   CCPResetIdle,
 131   CCPResetSentReq,
 132   CCPResetRcvdReq,
 133   CCPResetSentAck,
 134   CCPResetRcvdAck
 135 };
 136
 137 struct ippp_ccp_reset_state {
 138   enum ippp_ccp_reset_states state;     /* State of this transaction */
 139   struct ippp_struct *is;               /* Backlink to device stuff */
 140   unsigned char id;                     /* Backlink id index */
 141   unsigned char ta:1;                   /* The timer is active (flag) */
 142   unsigned char expra:1;                /* We expect a ResetAck at all */
 143   int dlen;                             /* Databytes stored in data */
 144   struct timer_list timer;              /* For timeouts/retries */
 145   /* This is a hack but seems sufficient for the moment. We do not want
 146      to have this be yet another allocation for some bytes, it is more
 147      memory management overhead than the whole mess is worth. */
 148   unsigned char data[IPPP_RESET_MAXDATABYTES];
 149 };
 150
 151 /* The data structure keeping track of the currently outstanding CCP Reset
 152    transactions. */
 153 struct ippp_ccp_reset {
 154   struct ippp_ccp_reset_state *rs[256]; /* One per possible id */
 155   unsigned char lastid;                 /* Last id allocated by the engine */
 156 };
 157
 158 struct ippp_struct {
 159   struct ippp_struct *next_link;
 160   int state;
 161   spinlock_t buflock;
 162   struct ippp_buf_queue rq[NUM_RCV_BUFFS]; /* packet queue for isdn_ppp_read() */
 163   struct ippp_buf_queue *first;  /* pointer to (current) first packet */
 164   struct ippp_buf_queue *last;   /* pointer to (current) last used packet in queue */
 165   wait_queue_head_t wq;
 166   struct task_struct *tk;
 167   unsigned int mpppcfg;
 168   unsigned int pppcfg;
 169   unsigned int mru;
 170   unsigned int mpmru;
 171   unsigned int mpmtu;
 172   unsigned int maxcid;
 173   struct isdn_net_local_s *lp;
 174   int unit;
 175   int minor;
 176   unsigned int last_link_seqno;
 177   long mp_seqno;
 178 #ifdef CONFIG_ISDN_PPP_VJ
 179   unsigned char *cbuf;
 180   struct slcompress *slcomp;
 181 #endif
 182 #ifdef CONFIG_IPPP_FILTER
 183   struct sock_filter *pass_filter;      /* filter for packets to pass */
 184   struct sock_filter *active_filter;    /* filter for pkts to reset idle */
 185   unsigned pass_len, active_len;
 186 #endif
 187   unsigned long debug;
 188   struct isdn_ppp_compressor *compressor,*decompressor;
 189   struct isdn_ppp_compressor *link_compressor,*link_decompressor;
 190   void *decomp_stat,*comp_stat,*link_decomp_stat,*link_comp_stat;
 191   struct ippp_ccp_reset *reset; /* Allocated on demand, may never be needed */
 192   unsigned long compflags;
 193 };
 194
 195 #endif /* _LINUX_ISDN_PPP_H */