net/sctp/primitive.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /* SCTP kernel implementation
0003  * Copyright (c) 1999-2000 Cisco, Inc.
0004  * Copyright (c) 1999-2001 Motorola, Inc.
0005  *
0006  * This file is part of the SCTP kernel implementation
0007  *
0008  * These functions implement the SCTP primitive functions from Section 10.
0009  *
0010  * Note that the descriptions from the specification are USER level
0011  * functions--this file is the functions which populate the struct proto
0012  * for SCTP which is the BOTTOM of the sockets interface.
0013  *
0014  * Please send any bug reports or fixes you make to the
0015  * email address(es):
0016  *    lksctp developers <linux-sctp@vger.kernel.org>
0017  *
0018  * Written or modified by:
0019  *    La Monte H.P. Yarroll <piggy@acm.org>
0020  *    Narasimha Budihal     <narasimha@refcode.org>
0021  *    Karl Knutson          <karl@athena.chicago.il.us>
0022  *    Ardelle Fan       <ardelle.fan@intel.com>
0023  *    Kevin Gao             <kevin.gao@intel.com>
0024  */
0025
0026 #include <linux/types.h>
0027 #include <linux/list.h> /* For struct list_head */
0028 #include <linux/socket.h>
0029 #include <linux/ip.h>
0030 #include <linux/time.h> /* For struct timeval */
0031 #include <linux/gfp.h>
0032 #include <net/sock.h>
0033 #include <net/sctp/sctp.h>
0034 #include <net/sctp/sm.h>
0035
0036 #define DECLARE_PRIMITIVE(name) \
0037 /* This is called in the code as sctp_primitive_ ## name.  */ \
0038 int sctp_primitive_ ## name(struct net *net, struct sctp_association *asoc, \
0039                 void *arg) { \
0040     int error = 0; \
0041     enum sctp_event_type event_type; union sctp_subtype subtype; \
0042     enum sctp_state state; \
0043     struct sctp_endpoint *ep; \
0044     \
0045     event_type = SCTP_EVENT_T_PRIMITIVE; \
0046     subtype = SCTP_ST_PRIMITIVE(SCTP_PRIMITIVE_ ## name); \
0047     state = asoc ? asoc->state : SCTP_STATE_CLOSED; \
0048     ep = asoc ? asoc->ep : NULL; \
0049     \
0050     error = sctp_do_sm(net, event_type, subtype, state, ep, asoc,   \
0051                arg, GFP_KERNEL); \
0052     return error; \
0053 }
0054
0055 /* 10.1 ULP-to-SCTP
0056  * B) Associate
0057  *
0058  * Format: ASSOCIATE(local SCTP instance name, destination transport addr,
0059  *         outbound stream count)
0060  * -> association id [,destination transport addr list] [,outbound stream
0061  *    count]
0062  *
0063  * This primitive allows the upper layer to initiate an association to a
0064  * specific peer endpoint.
0065  *
0066  * This version assumes that asoc is fully populated with the initial
0067  * parameters.  We then return a traditional kernel indicator of
0068  * success or failure.
0069  */
0070
0071 /* This is called in the code as sctp_primitive_ASSOCIATE.  */
0072
0073 DECLARE_PRIMITIVE(ASSOCIATE)
0074
0075 /* 10.1 ULP-to-SCTP
0076  * C) Shutdown
0077  *
0078  * Format: SHUTDOWN(association id)
0079  * -> result
0080  *
0081  * Gracefully closes an association. Any locally queued user data
0082  * will be delivered to the peer. The association will be terminated only
0083  * after the peer acknowledges all the SCTP packets sent.  A success code
0084  * will be returned on successful termination of the association. If
0085  * attempting to terminate the association results in a failure, an error
0086  * code shall be returned.
0087  */
0088
0089 DECLARE_PRIMITIVE(SHUTDOWN);
0090
0091 /* 10.1 ULP-to-SCTP
0092  * C) Abort
0093  *
0094  * Format: Abort(association id [, cause code])
0095  * -> result
0096  *
0097  * Ungracefully closes an association. Any locally queued user data
0098  * will be discarded and an ABORT chunk is sent to the peer. A success
0099  * code will be returned on successful abortion of the association. If
0100  * attempting to abort the association results in a failure, an error
0101  * code shall be returned.
0102  */
0103
0104 DECLARE_PRIMITIVE(ABORT);
0105
0106 /* 10.1 ULP-to-SCTP
0107  * E) Send
0108  *
0109  * Format: SEND(association id, buffer address, byte count [,context]
0110  *         [,stream id] [,life time] [,destination transport address]
0111  *         [,unorder flag] [,no-bundle flag] [,payload protocol-id] )
0112  * -> result
0113  *
0114  * This is the main method to send user data via SCTP.
0115  *
0116  * Mandatory attributes:
0117  *
0118  *  o association id - local handle to the SCTP association
0119  *
0120  *  o buffer address - the location where the user message to be
0121  *    transmitted is stored;
0122  *
0123  *  o byte count - The size of the user data in number of bytes;
0124  *
0125  * Optional attributes:
0126  *
0127  *  o context - an optional 32 bit integer that will be carried in the
0128  *    sending failure notification to the ULP if the transportation of
0129  *    this User Message fails.
0130  *
0131  *  o stream id - to indicate which stream to send the data on. If not
0132  *    specified, stream 0 will be used.
0133  *
0134  *  o life time - specifies the life time of the user data. The user data
0135  *    will not be sent by SCTP after the life time expires. This
0136  *    parameter can be used to avoid efforts to transmit stale
0137  *    user messages. SCTP notifies the ULP if the data cannot be
0138  *    initiated to transport (i.e. sent to the destination via SCTP's
0139  *    send primitive) within the life time variable. However, the
0140  *    user data will be transmitted if SCTP has attempted to transmit a
0141  *    chunk before the life time expired.
0142  *
0143  *  o destination transport address - specified as one of the destination
0144  *    transport addresses of the peer endpoint to which this packet
0145  *    should be sent. Whenever possible, SCTP should use this destination
0146  *    transport address for sending the packets, instead of the current
0147  *    primary path.
0148  *
0149  *  o unorder flag - this flag, if present, indicates that the user
0150  *    would like the data delivered in an unordered fashion to the peer
0151  *    (i.e., the U flag is set to 1 on all DATA chunks carrying this
0152  *    message).
0153  *
0154  *  o no-bundle flag - instructs SCTP not to bundle this user data with
0155  *    other outbound DATA chunks. SCTP MAY still bundle even when
0156  *    this flag is present, when faced with network congestion.
0157  *
0158  *  o payload protocol-id - A 32 bit unsigned integer that is to be
0159  *    passed to the peer indicating the type of payload protocol data
0160  *    being transmitted. This value is passed as opaque data by SCTP.
0161  */
0162
0163 DECLARE_PRIMITIVE(SEND);
0164
0165 /* 10.1 ULP-to-SCTP
0166  * J) Request Heartbeat
0167  *
0168  * Format: REQUESTHEARTBEAT(association id, destination transport address)
0169  *
0170  * -> result
0171  *
0172  * Instructs the local endpoint to perform a HeartBeat on the specified
0173  * destination transport address of the given association. The returned
0174  * result should indicate whether the transmission of the HEARTBEAT
0175  * chunk to the destination address is successful.
0176  *
0177  * Mandatory attributes:
0178  *
0179  * o association id - local handle to the SCTP association
0180  *
0181  * o destination transport address - the transport address of the
0182  *   association on which a heartbeat should be issued.
0183  */
0184
0185 DECLARE_PRIMITIVE(REQUESTHEARTBEAT);
0186
0187 /* ADDIP
0188 * 3.1.1 Address Configuration Change Chunk (ASCONF)
0189 *
0190 * This chunk is used to communicate to the remote endpoint one of the
0191 * configuration change requests that MUST be acknowledged.  The
0192 * information carried in the ASCONF Chunk uses the form of a
0193 * Type-Length-Value (TLV), as described in "3.2.1 Optional/
0194 * Variable-length Parameter Format" in RFC2960 [5], forall variable
0195 * parameters.
0196 */
0197
0198 DECLARE_PRIMITIVE(ASCONF);
0199
0200 /* RE-CONFIG 5.1 */
0201 DECLARE_PRIMITIVE(RECONF);