xref: /openbmc/linux/net/sctp/primitive.c (revision fb574682)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3  * Copyright (c) 1999-2000 Cisco, Inc.
4  * Copyright (c) 1999-2001 Motorola, Inc.
5  *
6  * This file is part of the SCTP kernel implementation
7  *
8  * These functions implement the SCTP primitive functions from Section 10.
9  *
10  * Note that the descriptions from the specification are USER level
11  * functions--this file is the functions which populate the struct proto
12  * for SCTP which is the BOTTOM of the sockets interface.
13  *
14  * Please send any bug reports or fixes you make to the
15  * email address(es):
16  *    lksctp developers <linux-sctp@vger.kernel.org>
17  *
18  * Written or modified by:
19  *    La Monte H.P. Yarroll <piggy@acm.org>
20  *    Narasimha Budihal     <narasimha@refcode.org>
21  *    Karl Knutson          <karl@athena.chicago.il.us>
22  *    Ardelle Fan	    <ardelle.fan@intel.com>
23  *    Kevin Gao             <kevin.gao@intel.com>
24  */
25 
26 #include <linux/types.h>
27 #include <linux/list.h> /* For struct list_head */
28 #include <linux/socket.h>
29 #include <linux/ip.h>
30 #include <linux/time.h> /* For struct timeval */
31 #include <linux/gfp.h>
32 #include <net/sock.h>
33 #include <net/sctp/sctp.h>
34 #include <net/sctp/sm.h>
35 
36 #define DECLARE_PRIMITIVE(name) \
37 /* This is called in the code as sctp_primitive_ ## name.  */ \
38 int sctp_primitive_ ## name(struct net *net, struct sctp_association *asoc, \
39 			    void *arg) { \
40 	int error = 0; \
41 	enum sctp_event_type event_type; union sctp_subtype subtype; \
42 	enum sctp_state state; \
43 	struct sctp_endpoint *ep; \
44 	\
45 	event_type = SCTP_EVENT_T_PRIMITIVE; \
46 	subtype = SCTP_ST_PRIMITIVE(SCTP_PRIMITIVE_ ## name); \
47 	state = asoc ? asoc->state : SCTP_STATE_CLOSED; \
48 	ep = asoc ? asoc->ep : NULL; \
49 	\
50 	error = sctp_do_sm(net, event_type, subtype, state, ep, asoc,	\
51 			   arg, GFP_KERNEL); \
52 	return error; \
53 }
54 
55 /* 10.1 ULP-to-SCTP
56  * B) Associate
57  *
58  * Format: ASSOCIATE(local SCTP instance name, destination transport addr,
59  *         outbound stream count)
60  * -> association id [,destination transport addr list] [,outbound stream
61  *    count]
62  *
63  * This primitive allows the upper layer to initiate an association to a
64  * specific peer endpoint.
65  *
66  * This version assumes that asoc is fully populated with the initial
67  * parameters.  We then return a traditional kernel indicator of
68  * success or failure.
69  */
70 
71 /* This is called in the code as sctp_primitive_ASSOCIATE.  */
72 
73 DECLARE_PRIMITIVE(ASSOCIATE)
74 
75 /* 10.1 ULP-to-SCTP
76  * C) Shutdown
77  *
78  * Format: SHUTDOWN(association id)
79  * -> result
80  *
81  * Gracefully closes an association. Any locally queued user data
82  * will be delivered to the peer. The association will be terminated only
83  * after the peer acknowledges all the SCTP packets sent.  A success code
84  * will be returned on successful termination of the association. If
85  * attempting to terminate the association results in a failure, an error
86  * code shall be returned.
87  */
88 
89 DECLARE_PRIMITIVE(SHUTDOWN);
90 
91 /* 10.1 ULP-to-SCTP
92  * C) Abort
93  *
94  * Format: Abort(association id [, cause code])
95  * -> result
96  *
97  * Ungracefully closes an association. Any locally queued user data
98  * will be discarded and an ABORT chunk is sent to the peer. A success
99  * code will be returned on successful abortion of the association. If
100  * attempting to abort the association results in a failure, an error
101  * code shall be returned.
102  */
103 
104 DECLARE_PRIMITIVE(ABORT);
105 
106 /* 10.1 ULP-to-SCTP
107  * E) Send
108  *
109  * Format: SEND(association id, buffer address, byte count [,context]
110  *         [,stream id] [,life time] [,destination transport address]
111  *         [,unorder flag] [,no-bundle flag] [,payload protocol-id] )
112  * -> result
113  *
114  * This is the main method to send user data via SCTP.
115  *
116  * Mandatory attributes:
117  *
118  *  o association id - local handle to the SCTP association
119  *
120  *  o buffer address - the location where the user message to be
121  *    transmitted is stored;
122  *
123  *  o byte count - The size of the user data in number of bytes;
124  *
125  * Optional attributes:
126  *
127  *  o context - an optional 32 bit integer that will be carried in the
128  *    sending failure notification to the ULP if the transportation of
129  *    this User Message fails.
130  *
131  *  o stream id - to indicate which stream to send the data on. If not
132  *    specified, stream 0 will be used.
133  *
134  *  o life time - specifies the life time of the user data. The user data
135  *    will not be sent by SCTP after the life time expires. This
136  *    parameter can be used to avoid efforts to transmit stale
137  *    user messages. SCTP notifies the ULP if the data cannot be
138  *    initiated to transport (i.e. sent to the destination via SCTP's
139  *    send primitive) within the life time variable. However, the
140  *    user data will be transmitted if SCTP has attempted to transmit a
141  *    chunk before the life time expired.
142  *
143  *  o destination transport address - specified as one of the destination
144  *    transport addresses of the peer endpoint to which this packet
145  *    should be sent. Whenever possible, SCTP should use this destination
146  *    transport address for sending the packets, instead of the current
147  *    primary path.
148  *
149  *  o unorder flag - this flag, if present, indicates that the user
150  *    would like the data delivered in an unordered fashion to the peer
151  *    (i.e., the U flag is set to 1 on all DATA chunks carrying this
152  *    message).
153  *
154  *  o no-bundle flag - instructs SCTP not to bundle this user data with
155  *    other outbound DATA chunks. SCTP MAY still bundle even when
156  *    this flag is present, when faced with network congestion.
157  *
158  *  o payload protocol-id - A 32 bit unsigned integer that is to be
159  *    passed to the peer indicating the type of payload protocol data
160  *    being transmitted. This value is passed as opaque data by SCTP.
161  */
162 
163 DECLARE_PRIMITIVE(SEND);
164 
165 /* 10.1 ULP-to-SCTP
166  * J) Request Heartbeat
167  *
168  * Format: REQUESTHEARTBEAT(association id, destination transport address)
169  *
170  * -> result
171  *
172  * Instructs the local endpoint to perform a HeartBeat on the specified
173  * destination transport address of the given association. The returned
174  * result should indicate whether the transmission of the HEARTBEAT
175  * chunk to the destination address is successful.
176  *
177  * Mandatory attributes:
178  *
179  * o association id - local handle to the SCTP association
180  *
181  * o destination transport address - the transport address of the
182  *   association on which a heartbeat should be issued.
183  */
184 
185 DECLARE_PRIMITIVE(REQUESTHEARTBEAT);
186 
187 /* ADDIP
188 * 3.1.1 Address Configuration Change Chunk (ASCONF)
189 *
190 * This chunk is used to communicate to the remote endpoint one of the
191 * configuration change requests that MUST be acknowledged.  The
192 * information carried in the ASCONF Chunk uses the form of a
193 * Type-Length-Value (TLV), as described in "3.2.1 Optional/
194 * Variable-length Parameter Format" in RFC2960 [5], forall variable
195 * parameters.
196 */
197 
198 DECLARE_PRIMITIVE(ASCONF);
199 
200 /* RE-CONFIG 5.1 */
201 DECLARE_PRIMITIVE(RECONF);
202