xref: /openbmc/linux/net/sctp/primitive.c (revision 2572f00d)
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);
214