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, write to
27  * the Free Software Foundation, 59 Temple Place - Suite 330,
28  * Boston, MA 02111-1307, USA.
29  *
30  * Please send any bug reports or fixes you make to the
31  * email address(es):
32  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
33  *
34  * Or submit a bug report through the following website:
35  *    http://www.sf.net/projects/lksctp
36  *
37  * Written or modified by:
38  *    La Monte H.P. Yarroll <piggy@acm.org>
39  *    Narasimha Budihal     <narasimha@refcode.org>
40  *    Karl Knutson          <karl@athena.chicago.il.us>
41  *    Ardelle Fan	    <ardelle.fan@intel.com>
42  *    Kevin Gao             <kevin.gao@intel.com>
43  *
44  * Any bugs reported given to us we will try to fix... any fixes shared will
45  * be incorporated into the next SCTP release.
46  */
47 
48 #include <linux/types.h>
49 #include <linux/list.h> /* For struct list_head */
50 #include <linux/socket.h>
51 #include <linux/ip.h>
52 #include <linux/time.h> /* For struct timeval */
53 #include <linux/gfp.h>
54 #include <net/sock.h>
55 #include <net/sctp/sctp.h>
56 #include <net/sctp/sm.h>
57 
58 #define DECLARE_PRIMITIVE(name) \
59 /* This is called in the code as sctp_primitive_ ## name.  */ \
60 int sctp_primitive_ ## name(struct sctp_association *asoc, \
61 			    void *arg) { \
62 	int error = 0; \
63 	sctp_event_t event_type; sctp_subtype_t subtype; \
64 	sctp_state_t state; \
65 	struct sctp_endpoint *ep; \
66 	\
67 	event_type = SCTP_EVENT_T_PRIMITIVE; \
68 	subtype = SCTP_ST_PRIMITIVE(SCTP_PRIMITIVE_ ## name); \
69 	state = asoc ? asoc->state : SCTP_STATE_CLOSED; \
70 	ep = asoc ? asoc->ep : NULL; \
71 	\
72 	error = sctp_do_sm(event_type, subtype, state, ep, asoc, \
73 			   arg, GFP_KERNEL); \
74 	return error; \
75 }
76 
77 /* 10.1 ULP-to-SCTP
78  * B) Associate
79  *
80  * Format: ASSOCIATE(local SCTP instance name, destination transport addr,
81  *         outbound stream count)
82  * -> association id [,destination transport addr list] [,outbound stream
83  *    count]
84  *
85  * This primitive allows the upper layer to initiate an association to a
86  * specific peer endpoint.
87  *
88  * This version assumes that asoc is fully populated with the initial
89  * parameters.  We then return a traditional kernel indicator of
90  * success or failure.
91  */
92 
93 /* This is called in the code as sctp_primitive_ASSOCIATE.  */
94 
95 DECLARE_PRIMITIVE(ASSOCIATE)
96 
97 /* 10.1 ULP-to-SCTP
98  * C) Shutdown
99  *
100  * Format: SHUTDOWN(association id)
101  * -> result
102  *
103  * Gracefully closes an association. Any locally queued user data
104  * will be delivered to the peer. The association will be terminated only
105  * after the peer acknowledges all the SCTP packets sent.  A success code
106  * will be returned on successful termination of the association. If
107  * attempting to terminate the association results in a failure, an error
108  * code shall be returned.
109  */
110 
111 DECLARE_PRIMITIVE(SHUTDOWN);
112 
113 /* 10.1 ULP-to-SCTP
114  * C) Abort
115  *
116  * Format: Abort(association id [, cause code])
117  * -> result
118  *
119  * Ungracefully closes an association. Any locally queued user data
120  * will be discarded and an ABORT chunk is sent to the peer. A success
121  * code will be returned on successful abortion of the association. If
122  * attempting to abort the association results in a failure, an error
123  * code shall be returned.
124  */
125 
126 DECLARE_PRIMITIVE(ABORT);
127 
128 /* 10.1 ULP-to-SCTP
129  * E) Send
130  *
131  * Format: SEND(association id, buffer address, byte count [,context]
132  *         [,stream id] [,life time] [,destination transport address]
133  *         [,unorder flag] [,no-bundle flag] [,payload protocol-id] )
134  * -> result
135  *
136  * This is the main method to send user data via SCTP.
137  *
138  * Mandatory attributes:
139  *
140  *  o association id - local handle to the SCTP association
141  *
142  *  o buffer address - the location where the user message to be
143  *    transmitted is stored;
144  *
145  *  o byte count - The size of the user data in number of bytes;
146  *
147  * Optional attributes:
148  *
149  *  o context - an optional 32 bit integer that will be carried in the
150  *    sending failure notification to the ULP if the transportation of
151  *    this User Message fails.
152  *
153  *  o stream id - to indicate which stream to send the data on. If not
154  *    specified, stream 0 will be used.
155  *
156  *  o life time - specifies the life time of the user data. The user data
157  *    will not be sent by SCTP after the life time expires. This
158  *    parameter can be used to avoid efforts to transmit stale
159  *    user messages. SCTP notifies the ULP if the data cannot be
160  *    initiated to transport (i.e. sent to the destination via SCTP's
161  *    send primitive) within the life time variable. However, the
162  *    user data will be transmitted if SCTP has attempted to transmit a
163  *    chunk before the life time expired.
164  *
165  *  o destination transport address - specified as one of the destination
166  *    transport addresses of the peer endpoint to which this packet
167  *    should be sent. Whenever possible, SCTP should use this destination
168  *    transport address for sending the packets, instead of the current
169  *    primary path.
170  *
171  *  o unorder flag - this flag, if present, indicates that the user
172  *    would like the data delivered in an unordered fashion to the peer
173  *    (i.e., the U flag is set to 1 on all DATA chunks carrying this
174  *    message).
175  *
176  *  o no-bundle flag - instructs SCTP not to bundle this user data with
177  *    other outbound DATA chunks. SCTP MAY still bundle even when
178  *    this flag is present, when faced with network congestion.
179  *
180  *  o payload protocol-id - A 32 bit unsigned integer that is to be
181  *    passed to the peer indicating the type of payload protocol data
182  *    being transmitted. This value is passed as opaque data by SCTP.
183  */
184 
185 DECLARE_PRIMITIVE(SEND);
186 
187 /* 10.1 ULP-to-SCTP
188  * J) Request Heartbeat
189  *
190  * Format: REQUESTHEARTBEAT(association id, destination transport address)
191  *
192  * -> result
193  *
194  * Instructs the local endpoint to perform a HeartBeat on the specified
195  * destination transport address of the given association. The returned
196  * result should indicate whether the transmission of the HEARTBEAT
197  * chunk to the destination address is successful.
198  *
199  * Mandatory attributes:
200  *
201  * o association id - local handle to the SCTP association
202  *
203  * o destination transport address - the transport address of the
204  *   association on which a heartbeat should be issued.
205  */
206 
207 DECLARE_PRIMITIVE(REQUESTHEARTBEAT);
208 
209 /* ADDIP
210 * 3.1.1 Address Configuration Change Chunk (ASCONF)
211 *
212 * This chunk is used to communicate to the remote endpoint one of the
213 * configuration change requests that MUST be acknowledged.  The
214 * information carried in the ASCONF Chunk uses the form of a
215 * Type-Length-Value (TLV), as described in "3.2.1 Optional/
216 * Variable-length Parameter Format" in RFC2960 [5], forall variable
217 * parameters.
218 */
219 
220 DECLARE_PRIMITIVE(ASCONF);
221