LXR linux/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
  43enum 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_PEER_NO_AUTH,   /* generate and send authentication event */
 104        SCTP_CMD_ASSOC_SHKEY,    /* generate the association shared keys */
 105        SCTP_CMD_T1_RETRAN,      /* Mark for retransmission after T1 timeout  */
 106        SCTP_CMD_UPDATE_INITTAG, /* Update peer inittag */
 107        SCTP_CMD_SEND_MSG,       /* Send the whole use message */
 108        SCTP_CMD_SEND_NEXT_ASCONF, /* Send the next ASCONF after ACK */
 109        SCTP_CMD_PURGE_ASCONF_QUEUE, /* Purge all asconf queues.*/
 110        SCTP_CMD_SET_ASOC,       /* Restore association context */
 111        SCTP_CMD_LAST
 112};
 113
 114/* How many commands can you put in an struct sctp_cmd_seq?
 115 * This is a rather arbitrary number, ideally derived from a careful
 116 * analysis of the state functions, but in reality just taken from
 117 * thin air in the hopes othat we don't trigger a kernel panic.
 118 */
 119#define SCTP_MAX_NUM_COMMANDS 20
 120
 121union sctp_arg {
 122        void *zero_all; /* Set to NULL to clear the entire union */
 123        __s32 i32;
 124        __u32 u32;
 125        __be32 be32;
 126        __u16 u16;
 127        __u8 u8;
 128        int error;
 129        __be16 err;
 130        enum sctp_state state;
 131        enum sctp_event_timeout to;
 132        struct sctp_chunk *chunk;
 133        struct sctp_association *asoc;
 134        struct sctp_transport *transport;
 135        struct sctp_bind_addr *bp;
 136        struct sctp_init_chunk *init;
 137        struct sctp_ulpevent *ulpevent;
 138        struct sctp_packet *packet;
 139        struct sctp_sackhdr *sackh;
 140        struct sctp_datamsg *msg;
 141};
 142
 143/* We are simulating ML type constructors here.
 144 *
 145 * SCTP_ARG_CONSTRUCTOR(NAME, TYPE, ELT) builds a function called
 146 * SCTP_NAME() which takes an argument of type TYPE and returns an
 147 * union sctp_arg.  It does this by inserting the sole argument into
 148 * the ELT union element of a local union sctp_arg.
 149 *
 150 * E.g., SCTP_ARG_CONSTRUCTOR(I32, __s32, i32) builds SCTP_I32(arg),
 151 * which takes an __s32 and returns a union sctp_arg containing the
 152 * __s32.  So, after foo = SCTP_I32(arg), foo.i32 == arg.
 153 */
 154
 155#define SCTP_ARG_CONSTRUCTOR(name, type, elt) \
 156static inline union sctp_arg    \
 157SCTP_## name (type arg)         \
 158{ union sctp_arg retval;\
 159  retval.zero_all = NULL;\
 160  retval.elt = arg;\
 161  return retval;\
 162}
 163
 164SCTP_ARG_CONSTRUCTOR(I32,       __s32, i32)
 165SCTP_ARG_CONSTRUCTOR(U32,       __u32, u32)
 166SCTP_ARG_CONSTRUCTOR(BE32,      __be32, be32)
 167SCTP_ARG_CONSTRUCTOR(U16,       __u16, u16)
 168SCTP_ARG_CONSTRUCTOR(U8,        __u8, u8)
 169SCTP_ARG_CONSTRUCTOR(ERROR,     int, error)
 170SCTP_ARG_CONSTRUCTOR(PERR,      __be16, err)    /* protocol error */
 171SCTP_ARG_CONSTRUCTOR(STATE,     enum sctp_state, state)
 172SCTP_ARG_CONSTRUCTOR(TO,        enum sctp_event_timeout, to)
 173SCTP_ARG_CONSTRUCTOR(CHUNK,     struct sctp_chunk *, chunk)
 174SCTP_ARG_CONSTRUCTOR(ASOC,      struct sctp_association *, asoc)
 175SCTP_ARG_CONSTRUCTOR(TRANSPORT, struct sctp_transport *, transport)
 176SCTP_ARG_CONSTRUCTOR(BA,        struct sctp_bind_addr *, bp)
 177SCTP_ARG_CONSTRUCTOR(PEER_INIT, struct sctp_init_chunk *, init)
 178SCTP_ARG_CONSTRUCTOR(ULPEVENT,  struct sctp_ulpevent *, ulpevent)
 179SCTP_ARG_CONSTRUCTOR(PACKET,    struct sctp_packet *, packet)
 180SCTP_ARG_CONSTRUCTOR(SACKH,     struct sctp_sackhdr *, sackh)
 181SCTP_ARG_CONSTRUCTOR(DATAMSG,   struct sctp_datamsg *, msg)
 182
 183static inline union sctp_arg SCTP_FORCE(void)
 184{
 185        return SCTP_I32(1);
 186}
 187
 188static inline union sctp_arg SCTP_NOFORCE(void)
 189{
 190        return SCTP_I32(0);
 191}
 192
 193static inline union sctp_arg SCTP_NULL(void)
 194{
 195        union sctp_arg retval;
 196        retval.zero_all = NULL;
 197        return retval;
 198}
 199
 200struct sctp_cmd {
 201        union sctp_arg obj;
 202        enum sctp_verb verb;
 203};
 204
 205struct sctp_cmd_seq {
 206        struct sctp_cmd cmds[SCTP_MAX_NUM_COMMANDS];
 207        struct sctp_cmd *last_used_slot;
 208        struct sctp_cmd *next_cmd;
 209};
 210
 211
 212/* Initialize a block of memory as a command sequence.
 213 * Return 0 if the initialization fails.
 214 */
 215static inline int sctp_init_cmd_seq(struct sctp_cmd_seq *seq)
 216{
 217        /* cmds[] is filled backwards to simplify the overflow BUG() check */
 218        seq->last_used_slot = seq->cmds + SCTP_MAX_NUM_COMMANDS;
 219        seq->next_cmd = seq->last_used_slot;
 220        return 1;               /* We always succeed.  */
 221}
 222
 223
 224/* Add a command to an struct sctp_cmd_seq.
 225 *
 226 * Use the SCTP_* constructors defined by SCTP_ARG_CONSTRUCTOR() above
 227 * to wrap data which goes in the obj argument.
 228 */
 229static inline void sctp_add_cmd_sf(struct sctp_cmd_seq *seq,
 230                                   enum sctp_verb verb, union sctp_arg obj)
 231{
 232        struct sctp_cmd *cmd = seq->last_used_slot - 1;
 233
 234        BUG_ON(cmd < seq->cmds);
 235
 236        cmd->verb = verb;
 237        cmd->obj = obj;
 238        seq->last_used_slot = cmd;
 239}
 240
 241/* Return the next command structure in an sctp_cmd_seq.
 242 * Return NULL at the end of the sequence.
 243 */
 244static inline struct sctp_cmd *sctp_next_cmd(struct sctp_cmd_seq *seq)
 245{
 246        if (seq->next_cmd <= seq->last_used_slot)
 247                return NULL;
 248
 249        return --seq->next_cmd;
 250}
 251
 252#endif /* __net_sctp_command_h__ */
 253