include/net/sctp/command.h

   1 /* SCTP kernel Implementation
   2  * (C) Copyright IBM Corp. 2001, 2004
   3  * Copyright (C) 1999-2001 Cisco, Motorola
   4  *
   5  * This file is part of the SCTP kernel implementation
   6  *
   7  * These are the definitions needed for the command object.
   8  *
   9  * This SCTP implementation  is free software;
  10  * you can redistribute it and/or modify it under the terms of
  11  * the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2, or (at your option)
  13  * any later version.
  14  *
  15  * This SCTP implementation  is distributed in the hope that it
  16  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  17  *                 ************************
  18  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  19  * See the GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with GNU CC; see the file COPYING.  If not, see
  23  * <http://www.gnu.org/licenses/>.
  24  *
  25  * Please send any bug reports or fixes you make to the
  26  * email address(es):
  27  *    lksctp developers <linux-sctp@vger.kernel.org>
  28  *
  29  * Written or modified by:
  30  *   La Monte H.P. Yarroll <piggy@acm.org>
  31  *   Karl Knutson <karl@athena.chicago.il.us>
  32  *   Ardelle Fan <ardelle.fan@intel.com>
  33  *   Sridhar Samudrala <sri@us.ibm.com>
  34  */
  35
  36 #ifndef __net_sctp_command_h__
  37 #define __net_sctp_command_h__
  38
  39 #include <net/sctp/constants.h>
  40 #include <net/sctp/structs.h>
  41
  42
  43 enum sctp_verb {
  44         SCTP_CMD_NOP = 0,       /* Do nothing. */
  45         SCTP_CMD_NEW_ASOC,      /* Register a new association.  */
  46         SCTP_CMD_DELETE_TCB,    /* Delete the current association. */
  47         SCTP_CMD_NEW_STATE,     /* Enter a new state.  */
  48         SCTP_CMD_REPORT_TSN,    /* Record the arrival of a TSN.  */
  49         SCTP_CMD_GEN_SACK,      /* Send a Selective ACK (maybe).  */
  50         SCTP_CMD_PROCESS_SACK,  /* Process an inbound SACK.  */
  51         SCTP_CMD_GEN_INIT_ACK,  /* Generate an INIT ACK chunk.  */
  52         SCTP_CMD_PEER_INIT,     /* Process a INIT from the peer.  */
  53         SCTP_CMD_GEN_COOKIE_ECHO, /* Generate a COOKIE ECHO chunk. */
  54         SCTP_CMD_CHUNK_ULP,     /* Send a chunk to the sockets layer.  */
  55         SCTP_CMD_EVENT_ULP,     /* Send a notification to the sockets layer. */
  56         SCTP_CMD_REPLY,         /* Send a chunk to our peer.  */
  57         SCTP_CMD_SEND_PKT,      /* Send a full packet to our peer.  */
  58         SCTP_CMD_RETRAN,        /* Mark a transport for retransmission.  */
  59         SCTP_CMD_ECN_CE,        /* Do delayed CE processing.   */
  60         SCTP_CMD_ECN_ECNE,      /* Do delayed ECNE processing. */
  61         SCTP_CMD_ECN_CWR,       /* Do delayed CWR processing.  */
  62         SCTP_CMD_TIMER_START,   /* Start a timer.  */
  63         SCTP_CMD_TIMER_START_ONCE, /* Start a timer once */
  64         SCTP_CMD_TIMER_RESTART, /* Restart a timer. */
  65         SCTP_CMD_TIMER_STOP,    /* Stop a timer. */
  66         SCTP_CMD_INIT_CHOOSE_TRANSPORT, /* Choose transport for an INIT. */
  67         SCTP_CMD_INIT_COUNTER_RESET, /* Reset init counter. */
  68         SCTP_CMD_INIT_COUNTER_INC,   /* Increment init counter. */
  69         SCTP_CMD_INIT_RESTART,  /* High level, do init timer work. */
  70         SCTP_CMD_COOKIEECHO_RESTART,  /* High level, do cookie-echo timer work. */
  71         SCTP_CMD_INIT_FAILED,   /* High level, do init failure work. */
  72         SCTP_CMD_REPORT_DUP,    /* Report a duplicate TSN.  */
  73         SCTP_CMD_STRIKE,        /* Mark a strike against a transport.  */
  74         SCTP_CMD_HB_TIMERS_START,    /* Start the heartbeat timers. */
  75         SCTP_CMD_HB_TIMER_UPDATE,    /* Update a heartbeat timers.  */
  76         SCTP_CMD_HB_TIMERS_STOP,     /* Stop the heartbeat timers.  */
  77         SCTP_CMD_TRANSPORT_HB_SENT,  /* Reset the status of a transport. */
  78         SCTP_CMD_TRANSPORT_IDLE,     /* Do manipulations on idle transport */
  79         SCTP_CMD_TRANSPORT_ON,       /* Mark the transport as active. */
  80         SCTP_CMD_REPORT_ERROR,   /* Pass this error back out of the sm. */
  81         SCTP_CMD_REPORT_BAD_TAG, /* Verification tags didn't match. */
  82         SCTP_CMD_PROCESS_CTSN,   /* Sideeffect from shutdown. */
  83         SCTP_CMD_ASSOC_FAILED,   /* Handle association failure. */
  84         SCTP_CMD_DISCARD_PACKET, /* Discard the whole packet. */
  85         SCTP_CMD_GEN_SHUTDOWN,   /* Generate a SHUTDOWN chunk. */
  86         SCTP_CMD_UPDATE_ASSOC,   /* Update association information. */
  87         SCTP_CMD_PURGE_OUTQUEUE, /* Purge all data waiting to be sent. */
  88         SCTP_CMD_SETUP_T2,       /* Hi-level, setup T2-shutdown parms.  */
  89         SCTP_CMD_RTO_PENDING,    /* Set transport's rto_pending. */
  90         SCTP_CMD_PART_DELIVER,   /* Partial data delivery considerations. */
  91         SCTP_CMD_RENEGE,         /* Renege data on an association. */
  92         SCTP_CMD_SETUP_T4,       /* ADDIP, setup T4 RTO timer parms. */
  93         SCTP_CMD_PROCESS_OPERR,  /* Process an ERROR chunk. */
  94         SCTP_CMD_REPORT_FWDTSN,  /* Report new cumulative TSN Ack. */
  95         SCTP_CMD_PROCESS_FWDTSN, /* Skips were reported, so process further. */
  96         SCTP_CMD_CLEAR_INIT_TAG, /* Clears association peer's inittag. */
  97         SCTP_CMD_DEL_NON_PRIMARY, /* Removes non-primary peer transports. */
  98         SCTP_CMD_T3_RTX_TIMERS_STOP, /* Stops T3-rtx pending timers */
  99         SCTP_CMD_FORCE_PRIM_RETRAN,  /* Forces retrans. over primary path. */
 100         SCTP_CMD_SET_SK_ERR,     /* Set sk_err */
 101         SCTP_CMD_ASSOC_CHANGE,   /* generate and send assoc_change event */
 102         SCTP_CMD_ADAPTATION_IND, /* generate and send adaptation event */
 103         SCTP_CMD_ASSOC_SHKEY,    /* generate the association shared keys */
 104         SCTP_CMD_T1_RETRAN,      /* Mark for retransmission after T1 timeout  */
 105         SCTP_CMD_UPDATE_INITTAG, /* Update peer inittag */
 106         SCTP_CMD_SEND_MSG,       /* Send the whole use message */
 107         SCTP_CMD_PURGE_ASCONF_QUEUE, /* Purge all asconf queues.*/
 108         SCTP_CMD_SET_ASOC,       /* Restore association context */
 109         SCTP_CMD_LAST
 110 };
 111
 112 /* How many commands can you put in an struct sctp_cmd_seq?
 113  * This is a rather arbitrary number, ideally derived from a careful
 114  * analysis of the state functions, but in reality just taken from
 115  * thin air in the hopes othat we don't trigger a kernel panic.
 116  */
 117 #define SCTP_MAX_NUM_COMMANDS 20
 118
 119 union sctp_arg {
 120         void *zero_all; /* Set to NULL to clear the entire union */
 121         __s32 i32;
 122         __u32 u32;
 123         __be32 be32;
 124         __u16 u16;
 125         __u8 u8;
 126         int error;
 127         __be16 err;
 128         enum sctp_state state;
 129         enum sctp_event_timeout to;
 130         struct sctp_chunk *chunk;
 131         struct sctp_association *asoc;
 132         struct sctp_transport *transport;
 133         struct sctp_bind_addr *bp;
 134         struct sctp_init_chunk *init;
 135         struct sctp_ulpevent *ulpevent;
 136         struct sctp_packet *packet;
 137         struct sctp_sackhdr *sackh;
 138         struct sctp_datamsg *msg;
 139 };
 140
 141 /* We are simulating ML type constructors here.
 142  *
 143  * SCTP_ARG_CONSTRUCTOR(NAME, TYPE, ELT) builds a function called
 144  * SCTP_NAME() which takes an argument of type TYPE and returns an
 145  * union sctp_arg.  It does this by inserting the sole argument into
 146  * the ELT union element of a local union sctp_arg.
 147  *
 148  * E.g., SCTP_ARG_CONSTRUCTOR(I32, __s32, i32) builds SCTP_I32(arg),
 149  * which takes an __s32 and returns a union sctp_arg containing the
 150  * __s32.  So, after foo = SCTP_I32(arg), foo.i32 == arg.
 151  */
 152
 153 #define SCTP_ARG_CONSTRUCTOR(name, type, elt) \
 154 static inline union sctp_arg    \
 155 SCTP_## name (type arg)         \
 156 { union sctp_arg retval;\
 157   retval.zero_all = NULL;\
 158   retval.elt = arg;\
 159   return retval;\
 160 }
 161
 162 SCTP_ARG_CONSTRUCTOR(I32,       __s32, i32)
 163 SCTP_ARG_CONSTRUCTOR(U32,       __u32, u32)
 164 SCTP_ARG_CONSTRUCTOR(BE32,      __be32, be32)
 165 SCTP_ARG_CONSTRUCTOR(U16,       __u16, u16)
 166 SCTP_ARG_CONSTRUCTOR(U8,        __u8, u8)
 167 SCTP_ARG_CONSTRUCTOR(ERROR,     int, error)
 168 SCTP_ARG_CONSTRUCTOR(PERR,      __be16, err)    /* protocol error */
 169 SCTP_ARG_CONSTRUCTOR(STATE,     enum sctp_state, state)
 170 SCTP_ARG_CONSTRUCTOR(TO,        enum sctp_event_timeout, to)
 171 SCTP_ARG_CONSTRUCTOR(CHUNK,     struct sctp_chunk *, chunk)
 172 SCTP_ARG_CONSTRUCTOR(ASOC,      struct sctp_association *, asoc)
 173 SCTP_ARG_CONSTRUCTOR(TRANSPORT, struct sctp_transport *, transport)
 174 SCTP_ARG_CONSTRUCTOR(BA,        struct sctp_bind_addr *, bp)
 175 SCTP_ARG_CONSTRUCTOR(PEER_INIT, struct sctp_init_chunk *, init)
 176 SCTP_ARG_CONSTRUCTOR(ULPEVENT,  struct sctp_ulpevent *, ulpevent)
 177 SCTP_ARG_CONSTRUCTOR(PACKET,    struct sctp_packet *, packet)
 178 SCTP_ARG_CONSTRUCTOR(SACKH,     struct sctp_sackhdr *, sackh)
 179 SCTP_ARG_CONSTRUCTOR(DATAMSG,   struct sctp_datamsg *, msg)
 180
 181 static inline union sctp_arg SCTP_FORCE(void)
 182 {
 183         return SCTP_I32(1);
 184 }
 185
 186 static inline union sctp_arg SCTP_NOFORCE(void)
 187 {
 188         return SCTP_I32(0);
 189 }
 190
 191 static inline union sctp_arg SCTP_NULL(void)
 192 {
 193         union sctp_arg retval;
 194         retval.zero_all = NULL;
 195         return retval;
 196 }
 197
 198 struct sctp_cmd {
 199         union sctp_arg obj;
 200         enum sctp_verb verb;
 201 };
 202
 203 struct sctp_cmd_seq {
 204         struct sctp_cmd cmds[SCTP_MAX_NUM_COMMANDS];
 205         struct sctp_cmd *last_used_slot;
 206         struct sctp_cmd *next_cmd;
 207 };
 208
 209
 210 /* Initialize a block of memory as a command sequence.
 211  * Return 0 if the initialization fails.
 212  */
 213 static inline int sctp_init_cmd_seq(struct sctp_cmd_seq *seq)
 214 {
 215         /* cmds[] is filled backwards to simplify the overflow BUG() check */
 216         seq->last_used_slot = seq->cmds + SCTP_MAX_NUM_COMMANDS;
 217         seq->next_cmd = seq->last_used_slot;
 218         return 1;               /* We always succeed.  */
 219 }
 220
 221
 222 /* Add a command to an struct sctp_cmd_seq.
 223  *
 224  * Use the SCTP_* constructors defined by SCTP_ARG_CONSTRUCTOR() above
 225  * to wrap data which goes in the obj argument.
 226  */
 227 static inline void sctp_add_cmd_sf(struct sctp_cmd_seq *seq,
 228                                    enum sctp_verb verb, union sctp_arg obj)
 229 {
 230         struct sctp_cmd *cmd = seq->last_used_slot - 1;
 231
 232         BUG_ON(cmd < seq->cmds);
 233
 234         cmd->verb = verb;
 235         cmd->obj = obj;
 236         seq->last_used_slot = cmd;
 237 }
 238
 239 /* Return the next command structure in an sctp_cmd_seq.
 240  * Return NULL at the end of the sequence.
 241  */
 242 static inline struct sctp_cmd *sctp_next_cmd(struct sctp_cmd_seq *seq)
 243 {
 244         if (seq->next_cmd <= seq->last_used_slot)
 245                 return NULL;
 246
 247         return --seq->next_cmd;
 248 }
 249
 250 #endif /* __net_sctp_command_h__ */