1/* SCTP kernel Implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (C) 1999-2001 Cisco, Motorola
4 *
5 * This file is part of the SCTP kernel implementation
6 *
7 * These are the definitions needed for the command object.
8 *
9 * This SCTP implementation  is free software;
10 * you can redistribute it and/or modify it under the terms of
11 * the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
13 * any later version.
14 *
15 * This SCTP implementation  is distributed in the hope that it
16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
17 *                 ************************
18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19 * See the GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with GNU CC; see the file COPYING.  If not, see
23 * <http://www.gnu.org/licenses/>.
24 *
25 * Please send any bug reports or fixes you make to the
26 * email address(es):
27 *    lksctp developers <linux-sctp@vger.kernel.org>
28 *
29 * Written or modified by:
30 *   La Monte H.P. Yarroll <piggy@acm.org>
31 *   Karl Knutson <karl@athena.chicago.il.us>
32 *   Ardelle Fan <ardelle.fan@intel.com>
33 *   Sridhar Samudrala <sri@us.ibm.com>
34 */
35
36#ifndef __net_sctp_command_h__
37#define __net_sctp_command_h__
38
39#include <net/sctp/constants.h>
40#include <net/sctp/structs.h>
41
42
43typedef enum {
44	SCTP_CMD_NOP = 0,	/* Do nothing. */
45	SCTP_CMD_NEW_ASOC,	/* Register a new association.  */
46	SCTP_CMD_DELETE_TCB,	/* Delete the current association. */
47	SCTP_CMD_NEW_STATE,	/* Enter a new state.  */
48	SCTP_CMD_REPORT_TSN,	/* Record the arrival of a TSN.  */
49	SCTP_CMD_GEN_SACK,	/* Send a Selective ACK (maybe).  */
50	SCTP_CMD_PROCESS_SACK,	/* Process an inbound SACK.  */
51	SCTP_CMD_GEN_INIT_ACK,	/* Generate an INIT ACK chunk.  */
52	SCTP_CMD_PEER_INIT,	/* Process a INIT from the peer.  */
53	SCTP_CMD_GEN_COOKIE_ECHO, /* Generate a COOKIE ECHO chunk. */
54	SCTP_CMD_CHUNK_ULP,	/* Send a chunk to the sockets layer.  */
55	SCTP_CMD_EVENT_ULP,	/* Send a notification to the sockets layer. */
56	SCTP_CMD_REPLY,		/* Send a chunk to our peer.  */
57	SCTP_CMD_SEND_PKT,	/* Send a full packet to our peer.  */
58	SCTP_CMD_RETRAN,	/* Mark a transport for retransmission.  */
59	SCTP_CMD_ECN_CE,        /* Do delayed CE processing.   */
60	SCTP_CMD_ECN_ECNE,	/* Do delayed ECNE processing. */
61	SCTP_CMD_ECN_CWR,	/* Do delayed CWR processing.  */
62	SCTP_CMD_TIMER_START,	/* Start a timer.  */
63	SCTP_CMD_TIMER_START_ONCE, /* Start a timer once */
64	SCTP_CMD_TIMER_RESTART,	/* Restart a timer. */
65	SCTP_CMD_TIMER_STOP,	/* Stop a timer. */
66	SCTP_CMD_INIT_CHOOSE_TRANSPORT, /* Choose transport for an INIT. */
67	SCTP_CMD_INIT_COUNTER_RESET, /* Reset init counter. */
68	SCTP_CMD_INIT_COUNTER_INC,   /* Increment init counter. */
69	SCTP_CMD_INIT_RESTART,  /* High level, do init timer work. */
70	SCTP_CMD_COOKIEECHO_RESTART,  /* High level, do cookie-echo timer work. */
71	SCTP_CMD_INIT_FAILED,   /* High level, do init failure work. */
72	SCTP_CMD_REPORT_DUP,	/* Report a duplicate TSN.  */
73	SCTP_CMD_STRIKE,	/* Mark a strike against a transport.  */
74	SCTP_CMD_HB_TIMERS_START,    /* Start the heartbeat timers. */
75	SCTP_CMD_HB_TIMER_UPDATE,    /* Update a heartbeat timers.  */
76	SCTP_CMD_HB_TIMERS_STOP,     /* Stop the heartbeat timers.  */
77	SCTP_CMD_TRANSPORT_HB_SENT,  /* Reset the status of a transport. */
78	SCTP_CMD_TRANSPORT_IDLE,     /* Do manipulations on idle transport */
79	SCTP_CMD_TRANSPORT_ON,       /* Mark the transport as active. */
80	SCTP_CMD_REPORT_ERROR,   /* Pass this error back out of the sm. */
81	SCTP_CMD_REPORT_BAD_TAG, /* Verification tags didn't match. */
82	SCTP_CMD_PROCESS_CTSN,   /* Sideeffect from shutdown. */
83	SCTP_CMD_ASSOC_FAILED,	 /* Handle association failure. */
84	SCTP_CMD_DISCARD_PACKET, /* Discard the whole packet. */
85	SCTP_CMD_GEN_SHUTDOWN,   /* Generate a SHUTDOWN chunk. */
86	SCTP_CMD_UPDATE_ASSOC,   /* Update association information. */
87	SCTP_CMD_PURGE_OUTQUEUE, /* Purge all data waiting to be sent. */
88	SCTP_CMD_SETUP_T2,       /* Hi-level, setup T2-shutdown parms.  */
89	SCTP_CMD_RTO_PENDING,	 /* Set transport's rto_pending. */
90	SCTP_CMD_PART_DELIVER,	 /* Partial data delivery considerations. */
91	SCTP_CMD_RENEGE,         /* Renege data on an association. */
92	SCTP_CMD_SETUP_T4,	 /* ADDIP, setup T4 RTO timer parms. */
93	SCTP_CMD_PROCESS_OPERR,  /* Process an ERROR chunk. */
94	SCTP_CMD_REPORT_FWDTSN,	 /* Report new cumulative TSN Ack. */
95	SCTP_CMD_PROCESS_FWDTSN, /* Skips were reported, so process further. */
96	SCTP_CMD_CLEAR_INIT_TAG, /* Clears association peer's inittag. */
97	SCTP_CMD_DEL_NON_PRIMARY, /* Removes non-primary peer transports. */
98	SCTP_CMD_T3_RTX_TIMERS_STOP, /* Stops T3-rtx pending timers */
99	SCTP_CMD_FORCE_PRIM_RETRAN,  /* Forces retrans. over primary path. */
100	SCTP_CMD_SET_SK_ERR,	 /* Set sk_err */
101	SCTP_CMD_ASSOC_CHANGE,	 /* generate and send assoc_change event */
102	SCTP_CMD_ADAPTATION_IND, /* generate and send adaptation event */
103	SCTP_CMD_ASSOC_SHKEY,    /* generate the association shared keys */
104	SCTP_CMD_T1_RETRAN,	 /* Mark for retransmission after T1 timeout  */
105	SCTP_CMD_UPDATE_INITTAG, /* Update peer inittag */
106	SCTP_CMD_SEND_MSG,	 /* Send the whole use message */
107	SCTP_CMD_SEND_NEXT_ASCONF, /* Send the next ASCONF after ACK */
108	SCTP_CMD_PURGE_ASCONF_QUEUE, /* Purge all asconf queues.*/
109	SCTP_CMD_SET_ASOC,	 /* Restore association context */
110	SCTP_CMD_LAST
111} sctp_verb_t;
112
113/* How many commands can you put in an sctp_cmd_seq_t?
114 * This is a rather arbitrary number, ideally derived from a careful
115 * analysis of the state functions, but in reality just taken from
116 * thin air in the hopes othat we don't trigger a kernel panic.
117 */
118#define SCTP_MAX_NUM_COMMANDS 20
119
120typedef union {
121	void *zero_all;	/* Set to NULL to clear the entire union */
122	__s32 i32;
123	__u32 u32;
124	__be32 be32;
125	__u16 u16;
126	__u8 u8;
127	int error;
128	__be16 err;
129	sctp_state_t state;
130	sctp_event_timeout_t to;
131	struct sctp_chunk *chunk;
132	struct sctp_association *asoc;
133	struct sctp_transport *transport;
134	struct sctp_bind_addr *bp;
135	sctp_init_chunk_t *init;
136	struct sctp_ulpevent *ulpevent;
137	struct sctp_packet *packet;
138	sctp_sackhdr_t *sackh;
139	struct sctp_datamsg *msg;
140} sctp_arg_t;
141
142/* We are simulating ML type constructors here.
143 *
144 * SCTP_ARG_CONSTRUCTOR(NAME, TYPE, ELT) builds a function called
145 * SCTP_NAME() which takes an argument of type TYPE and returns an
146 * sctp_arg_t.  It does this by inserting the sole argument into the
147 * ELT union element of a local sctp_arg_t.
148 *
149 * E.g., SCTP_ARG_CONSTRUCTOR(I32, __s32, i32) builds SCTP_I32(arg),
150 * which takes an __s32 and returns a sctp_arg_t containing the
151 * __s32.  So, after foo = SCTP_I32(arg), foo.i32 == arg.
152 */
153
154#define SCTP_ARG_CONSTRUCTOR(name, type, elt) \
155static inline sctp_arg_t	\
156SCTP_## name (type arg)		\
157{ sctp_arg_t retval;\
158  retval.zero_all = NULL;\
159  retval.elt = arg;\
160  return retval;\
161}
162
163SCTP_ARG_CONSTRUCTOR(I32,	__s32, i32)
164SCTP_ARG_CONSTRUCTOR(U32,	__u32, u32)
165SCTP_ARG_CONSTRUCTOR(BE32,	__be32, be32)
166SCTP_ARG_CONSTRUCTOR(U16,	__u16, u16)
167SCTP_ARG_CONSTRUCTOR(U8,	__u8, u8)
168SCTP_ARG_CONSTRUCTOR(ERROR,     int, error)
169SCTP_ARG_CONSTRUCTOR(PERR,      __be16, err)	/* protocol error */
170SCTP_ARG_CONSTRUCTOR(STATE,	sctp_state_t, state)
171SCTP_ARG_CONSTRUCTOR(TO,	sctp_event_timeout_t, to)
172SCTP_ARG_CONSTRUCTOR(CHUNK,	struct sctp_chunk *, chunk)
173SCTP_ARG_CONSTRUCTOR(ASOC,	struct sctp_association *, asoc)
174SCTP_ARG_CONSTRUCTOR(TRANSPORT,	struct sctp_transport *, transport)
175SCTP_ARG_CONSTRUCTOR(BA,	struct sctp_bind_addr *, bp)
176SCTP_ARG_CONSTRUCTOR(PEER_INIT,	sctp_init_chunk_t *, init)
177SCTP_ARG_CONSTRUCTOR(ULPEVENT,  struct sctp_ulpevent *, ulpevent)
178SCTP_ARG_CONSTRUCTOR(PACKET,	struct sctp_packet *, packet)
179SCTP_ARG_CONSTRUCTOR(SACKH,	sctp_sackhdr_t *, sackh)
180SCTP_ARG_CONSTRUCTOR(DATAMSG,	struct sctp_datamsg *, msg)
181
182static inline sctp_arg_t SCTP_FORCE(void)
183{
184	return SCTP_I32(1);
185}
186
187static inline sctp_arg_t SCTP_NOFORCE(void)
188{
189	return SCTP_I32(0);
190}
191
192static inline sctp_arg_t SCTP_NULL(void)
193{
194	sctp_arg_t retval;
195	retval.zero_all = NULL;
196	return retval;
197}
198
199typedef struct {
200	sctp_arg_t obj;
201	sctp_verb_t verb;
202} sctp_cmd_t;
203
204typedef struct {
205	sctp_cmd_t cmds[SCTP_MAX_NUM_COMMANDS];
206	sctp_cmd_t *last_used_slot;
207	sctp_cmd_t *next_cmd;
208} sctp_cmd_seq_t;
209
210
211/* Initialize a block of memory as a command sequence.
212 * Return 0 if the initialization fails.
213 */
214static inline int sctp_init_cmd_seq(sctp_cmd_seq_t *seq)
215{
216	/* cmds[] is filled backwards to simplify the overflow BUG() check */
217	seq->last_used_slot = seq->cmds + SCTP_MAX_NUM_COMMANDS;
218	seq->next_cmd = seq->last_used_slot;
219	return 1;		/* We always succeed.  */
220}
221
222
223/* Add a command to an sctp_cmd_seq_t.
224 *
225 * Use the SCTP_* constructors defined by SCTP_ARG_CONSTRUCTOR() above
226 * to wrap data which goes in the obj argument.
227 */
228static inline void sctp_add_cmd_sf(sctp_cmd_seq_t *seq, sctp_verb_t verb,
229				   sctp_arg_t obj)
230{
231	sctp_cmd_t *cmd = seq->last_used_slot - 1;
232
233	BUG_ON(cmd < seq->cmds);
234
235	cmd->verb = verb;
236	cmd->obj = obj;
237	seq->last_used_slot = cmd;
238}
239
240/* Return the next command structure in an sctp_cmd_seq.
241 * Return NULL at the end of the sequence.
242 */
243static inline sctp_cmd_t *sctp_next_cmd(sctp_cmd_seq_t *seq)
244{
245	if (seq->next_cmd <= seq->last_used_slot)
246		return NULL;
247
248	return --seq->next_cmd;
249}
250
251#endif /* __net_sctp_command_h__ */
252