net/sctp/primitive.c

   1 /* SCTP kernel implementation
   2  * Copyright (c) 1999-2000 Cisco, Inc.
   3  * Copyright (c) 1999-2001 Motorola, Inc.
   4  *
   5  * This file is part of the SCTP kernel implementation
   6  *
   7  * These functions implement the SCTP primitive functions from Section 10.
   8  *
   9  * Note that the descriptions from the specification are USER level
  10  * functions--this file is the functions which populate the struct proto
  11  * for SCTP which is the BOTTOM of the sockets interface.
  12  *
  13  * This SCTP implementation is free software;
  14  * you can redistribute it and/or modify it under the terms of
  15  * the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  * This SCTP implementation is distributed in the hope that it
  20  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  21  *                 ************************
  22  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  23  * See the GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License
  26  * along with GNU CC; see the file COPYING.  If not, see
  27  * <http://www.gnu.org/licenses/>.
  28  *
  29  * Please send any bug reports or fixes you make to the
  30  * email address(es):
  31  *    lksctp developers <linux-sctp@vger.kernel.org>
  32  *
  33  * Written or modified by:
  34  *    La Monte H.P. Yarroll <piggy@acm.org>
  35  *    Narasimha Budihal     <narasimha@refcode.org>
  36  *    Karl Knutson          <karl@athena.chicago.il.us>
  37  *    Ardelle Fan           <ardelle.fan@intel.com>
  38  *    Kevin Gao             <kevin.gao@intel.com>
  39  */
  40
  41 #include <linux/types.h>
  42 #include <linux/list.h> /* For struct list_head */
  43 #include <linux/socket.h>
  44 #include <linux/ip.h>
  45 #include <linux/time.h> /* For struct timeval */
  46 #include <linux/gfp.h>
  47 #include <net/sock.h>
  48 #include <net/sctp/sctp.h>
  49 #include <net/sctp/sm.h>
  50
  51 #define DECLARE_PRIMITIVE(name) \
  52 /* This is called in the code as sctp_primitive_ ## name.  */ \
  53 int sctp_primitive_ ## name(struct net *net, struct sctp_association *asoc, \
  54                             void *arg) { \
  55         int error = 0; \
  56         sctp_event_t event_type; sctp_subtype_t subtype; \
  57         sctp_state_t state; \
  58         struct sctp_endpoint *ep; \
  59         \
  60         event_type = SCTP_EVENT_T_PRIMITIVE; \
  61         subtype = SCTP_ST_PRIMITIVE(SCTP_PRIMITIVE_ ## name); \
  62         state = asoc ? asoc->state : SCTP_STATE_CLOSED; \
  63         ep = asoc ? asoc->ep : NULL; \
  64         \
  65         error = sctp_do_sm(net, event_type, subtype, state, ep, asoc,   \
  66                            arg, GFP_KERNEL); \
  67         return error; \
  68 }
  69
  70 /* 10.1 ULP-to-SCTP
  71  * B) Associate
  72  *
  73  * Format: ASSOCIATE(local SCTP instance name, destination transport addr,
  74  *         outbound stream count)
  75  * -> association id [,destination transport addr list] [,outbound stream
  76  *    count]
  77  *
  78  * This primitive allows the upper layer to initiate an association to a
  79  * specific peer endpoint.
  80  *
  81  * This version assumes that asoc is fully populated with the initial
  82  * parameters.  We then return a traditional kernel indicator of
  83  * success or failure.
  84  */
  85
  86 /* This is called in the code as sctp_primitive_ASSOCIATE.  */
  87
  88 DECLARE_PRIMITIVE(ASSOCIATE)
  89
  90 /* 10.1 ULP-to-SCTP
  91  * C) Shutdown
  92  *
  93  * Format: SHUTDOWN(association id)
  94  * -> result
  95  *
  96  * Gracefully closes an association. Any locally queued user data
  97  * will be delivered to the peer. The association will be terminated only
  98  * after the peer acknowledges all the SCTP packets sent.  A success code
  99  * will be returned on successful termination of the association. If
 100  * attempting to terminate the association results in a failure, an error
 101  * code shall be returned.
 102  */
 103
 104 DECLARE_PRIMITIVE(SHUTDOWN);
 105
 106 /* 10.1 ULP-to-SCTP
 107  * C) Abort
 108  *
 109  * Format: Abort(association id [, cause code])
 110  * -> result
 111  *
 112  * Ungracefully closes an association. Any locally queued user data
 113  * will be discarded and an ABORT chunk is sent to the peer. A success
 114  * code will be returned on successful abortion of the association. If
 115  * attempting to abort the association results in a failure, an error
 116  * code shall be returned.
 117  */
 118
 119 DECLARE_PRIMITIVE(ABORT);
 120
 121 /* 10.1 ULP-to-SCTP
 122  * E) Send
 123  *
 124  * Format: SEND(association id, buffer address, byte count [,context]
 125  *         [,stream id] [,life time] [,destination transport address]
 126  *         [,unorder flag] [,no-bundle flag] [,payload protocol-id] )
 127  * -> result
 128  *
 129  * This is the main method to send user data via SCTP.
 130  *
 131  * Mandatory attributes:
 132  *
 133  *  o association id - local handle to the SCTP association
 134  *
 135  *  o buffer address - the location where the user message to be
 136  *    transmitted is stored;
 137  *
 138  *  o byte count - The size of the user data in number of bytes;
 139  *
 140  * Optional attributes:
 141  *
 142  *  o context - an optional 32 bit integer that will be carried in the
 143  *    sending failure notification to the ULP if the transportation of
 144  *    this User Message fails.
 145  *
 146  *  o stream id - to indicate which stream to send the data on. If not
 147  *    specified, stream 0 will be used.
 148  *
 149  *  o life time - specifies the life time of the user data. The user data
 150  *    will not be sent by SCTP after the life time expires. This
 151  *    parameter can be used to avoid efforts to transmit stale
 152  *    user messages. SCTP notifies the ULP if the data cannot be
 153  *    initiated to transport (i.e. sent to the destination via SCTP's
 154  *    send primitive) within the life time variable. However, the
 155  *    user data will be transmitted if SCTP has attempted to transmit a
 156  *    chunk before the life time expired.
 157  *
 158  *  o destination transport address - specified as one of the destination
 159  *    transport addresses of the peer endpoint to which this packet
 160  *    should be sent. Whenever possible, SCTP should use this destination
 161  *    transport address for sending the packets, instead of the current
 162  *    primary path.
 163  *
 164  *  o unorder flag - this flag, if present, indicates that the user
 165  *    would like the data delivered in an unordered fashion to the peer
 166  *    (i.e., the U flag is set to 1 on all DATA chunks carrying this
 167  *    message).
 168  *
 169  *  o no-bundle flag - instructs SCTP not to bundle this user data with
 170  *    other outbound DATA chunks. SCTP MAY still bundle even when
 171  *    this flag is present, when faced with network congestion.
 172  *
 173  *  o payload protocol-id - A 32 bit unsigned integer that is to be
 174  *    passed to the peer indicating the type of payload protocol data
 175  *    being transmitted. This value is passed as opaque data by SCTP.
 176  */
 177
 178 DECLARE_PRIMITIVE(SEND);
 179
 180 /* 10.1 ULP-to-SCTP
 181  * J) Request Heartbeat
 182  *
 183  * Format: REQUESTHEARTBEAT(association id, destination transport address)
 184  *
 185  * -> result
 186  *
 187  * Instructs the local endpoint to perform a HeartBeat on the specified
 188  * destination transport address of the given association. The returned
 189  * result should indicate whether the transmission of the HEARTBEAT
 190  * chunk to the destination address is successful.
 191  *
 192  * Mandatory attributes:
 193  *
 194  * o association id - local handle to the SCTP association
 195  *
 196  * o destination transport address - the transport address of the
 197  *   association on which a heartbeat should be issued.
 198  */
 199
 200 DECLARE_PRIMITIVE(REQUESTHEARTBEAT);
 201
 202 /* ADDIP
 203 * 3.1.1 Address Configuration Change Chunk (ASCONF)
 204 *
 205 * This chunk is used to communicate to the remote endpoint one of the
 206 * configuration change requests that MUST be acknowledged.  The
 207 * information carried in the ASCONF Chunk uses the form of a
 208 * Type-Length-Value (TLV), as described in "3.2.1 Optional/
 209 * Variable-length Parameter Format" in RFC2960 [5], forall variable
 210 * parameters.
 211 */
 212
 213 DECLARE_PRIMITIVE(ASCONF);