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1/* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2001, 2004
3 * Copyright (c) 1999-2000 Cisco, Inc.
4 * Copyright (c) 1999-2001 Motorola, Inc.
5 * Copyright (c) 2001 Intel Corp.
6 *
7 * This file is part of the SCTP kernel implementation
8 *
9 * These are the definitions needed for the tsnmap type. The tsnmap is used
10 * to track out of order TSNs received.
11 *
12 * This SCTP implementation is free software;
13 * you can redistribute it and/or modify it under the terms of
14 * the GNU General Public License as published by
15 * the Free Software Foundation; either version 2, or (at your option)
16 * any later version.
17 *
18 * This SCTP implementation is distributed in the hope that it
19 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
20 * ************************
21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
22 * See the GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with GNU CC; see the file COPYING. If not, write to
26 * the Free Software Foundation, 59 Temple Place - Suite 330,
27 * Boston, MA 02111-1307, USA.
28 *
29 * Please send any bug reports or fixes you make to the
30 * email address(es):
31 * lksctp developers <lksctp-developers@lists.sourceforge.net>
32 *
33 * Or submit a bug report through the following website:
34 * http://www.sf.net/projects/lksctp
35 *
36 * Written or modified by:
37 * Jon Grimm <jgrimm@us.ibm.com>
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Karl Knutson <karl@athena.chicago.il.us>
40 * Sridhar Samudrala <sri@us.ibm.com>
41 *
42 * Any bugs reported given to us we will try to fix... any fixes shared will
43 * be incorporated into the next SCTP release.
44 */
45#include <net/sctp/constants.h>
46
47#ifndef __sctp_tsnmap_h__
48#define __sctp_tsnmap_h__
49
50/* RFC 2960 12.2 Parameters necessary per association (i.e. the TCB)
51 * Mapping An array of bits or bytes indicating which out of
52 * Array order TSN's have been received (relative to the
53 * Last Rcvd TSN). If no gaps exist, i.e. no out of
54 * order packets have been received, this array
55 * will be set to all zero. This structure may be
56 * in the form of a circular buffer or bit array.
57 */
58struct sctp_tsnmap {
59 /* This array counts the number of chunks with each TSN.
60 * It points at one of the two buffers with which we will
61 * ping-pong between.
62 */
63 unsigned long *tsn_map;
64
65 /* This is the TSN at tsn_map[0]. */
66 __u32 base_tsn;
67
68 /* Last Rcvd : This is the last TSN received in
69 * TSN : sequence. This value is set initially by
70 * : taking the peer's Initial TSN, received in
71 * : the INIT or INIT ACK chunk, and subtracting
72 * : one from it.
73 *
74 * Throughout most of the specification this is called the
75 * "Cumulative TSN ACK Point". In this case, we
76 * ignore the advice in 12.2 in favour of the term
77 * used in the bulk of the text.
78 */
79 __u32 cumulative_tsn_ack_point;
80
81 /* This is the highest TSN we've marked. */
82 __u32 max_tsn_seen;
83
84 /* This is the minimum number of TSNs we can track. This corresponds
85 * to the size of tsn_map. Note: the overflow_map allows us to
86 * potentially track more than this quantity.
87 */
88 __u16 len;
89
90 /* Data chunks pending receipt. used by SCTP_STATUS sockopt */
91 __u16 pending_data;
92
93 /* Record duplicate TSNs here. We clear this after
94 * every SACK. Store up to SCTP_MAX_DUP_TSNS worth of
95 * information.
96 */
97 __u16 num_dup_tsns;
98 __be32 dup_tsns[SCTP_MAX_DUP_TSNS];
99};
100
101struct sctp_tsnmap_iter {
102 __u32 start;
103};
104
105/* Initialize a block of memory as a tsnmap. */
106struct sctp_tsnmap *sctp_tsnmap_init(struct sctp_tsnmap *, __u16 len,
107 __u32 initial_tsn, gfp_t gfp);
108
109void sctp_tsnmap_free(struct sctp_tsnmap *map);
110
111/* Test the tracking state of this TSN.
112 * Returns:
113 * 0 if the TSN has not yet been seen
114 * >0 if the TSN has been seen (duplicate)
115 * <0 if the TSN is invalid (too large to track)
116 */
117int sctp_tsnmap_check(const struct sctp_tsnmap *, __u32 tsn);
118
119/* Mark this TSN as seen. */
120int sctp_tsnmap_mark(struct sctp_tsnmap *, __u32 tsn);
121
122/* Mark this TSN and all lower as seen. */
123void sctp_tsnmap_skip(struct sctp_tsnmap *map, __u32 tsn);
124
125/* Retrieve the Cumulative TSN ACK Point. */
126static inline __u32 sctp_tsnmap_get_ctsn(const struct sctp_tsnmap *map)
127{
128 return map->cumulative_tsn_ack_point;
129}
130
131/* Retrieve the highest TSN we've seen. */
132static inline __u32 sctp_tsnmap_get_max_tsn_seen(const struct sctp_tsnmap *map)
133{
134 return map->max_tsn_seen;
135}
136
137/* How many duplicate TSNs are stored? */
138static inline __u16 sctp_tsnmap_num_dups(struct sctp_tsnmap *map)
139{
140 return map->num_dup_tsns;
141}
142
143/* Return pointer to duplicate tsn array as needed by SACK. */
144static inline __be32 *sctp_tsnmap_get_dups(struct sctp_tsnmap *map)
145{
146 map->num_dup_tsns = 0;
147 return map->dup_tsns;
148}
149
150/* How many gap ack blocks do we have recorded? */
151__u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map,
152 struct sctp_gap_ack_block *gabs);
153
154/* Refresh the count on pending data. */
155__u16 sctp_tsnmap_pending(struct sctp_tsnmap *map);
156
157/* Is there a gap in the TSN map? */
158static inline int sctp_tsnmap_has_gap(const struct sctp_tsnmap *map)
159{
160 return map->cumulative_tsn_ack_point != map->max_tsn_seen;
161}
162
163/* Mark a duplicate TSN. Note: limit the storage of duplicate TSN
164 * information.
165 */
166static inline void sctp_tsnmap_mark_dup(struct sctp_tsnmap *map, __u32 tsn)
167{
168 if (map->num_dup_tsns < SCTP_MAX_DUP_TSNS)
169 map->dup_tsns[map->num_dup_tsns++] = htonl(tsn);
170}
171
172/* Renege a TSN that was seen. */
173void sctp_tsnmap_renege(struct sctp_tsnmap *, __u32 tsn);
174
175/* Is there a gap in the TSN map? */
176int sctp_tsnmap_has_gap(const struct sctp_tsnmap *);
177
178#endif /* __sctp_tsnmap_h__ */
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/* SCTP kernel implementation
3 * (C) Copyright IBM Corp. 2001, 2004
4 * Copyright (c) 1999-2000 Cisco, Inc.
5 * Copyright (c) 1999-2001 Motorola, Inc.
6 * Copyright (c) 2001 Intel Corp.
7 *
8 * This file is part of the SCTP kernel implementation
9 *
10 * These are the definitions needed for the tsnmap type. The tsnmap is used
11 * to track out of order TSNs received.
12 *
13 * Please send any bug reports or fixes you make to the
14 * email address(es):
15 * lksctp developers <linux-sctp@vger.kernel.org>
16 *
17 * Written or modified by:
18 * Jon Grimm <jgrimm@us.ibm.com>
19 * La Monte H.P. Yarroll <piggy@acm.org>
20 * Karl Knutson <karl@athena.chicago.il.us>
21 * Sridhar Samudrala <sri@us.ibm.com>
22 */
23#include <net/sctp/constants.h>
24
25#ifndef __sctp_tsnmap_h__
26#define __sctp_tsnmap_h__
27
28/* RFC 2960 12.2 Parameters necessary per association (i.e. the TCB)
29 * Mapping An array of bits or bytes indicating which out of
30 * Array order TSN's have been received (relative to the
31 * Last Rcvd TSN). If no gaps exist, i.e. no out of
32 * order packets have been received, this array
33 * will be set to all zero. This structure may be
34 * in the form of a circular buffer or bit array.
35 */
36struct sctp_tsnmap {
37 /* This array counts the number of chunks with each TSN.
38 * It points at one of the two buffers with which we will
39 * ping-pong between.
40 */
41 unsigned long *tsn_map;
42
43 /* This is the TSN at tsn_map[0]. */
44 __u32 base_tsn;
45
46 /* Last Rcvd : This is the last TSN received in
47 * TSN : sequence. This value is set initially by
48 * : taking the peer's Initial TSN, received in
49 * : the INIT or INIT ACK chunk, and subtracting
50 * : one from it.
51 *
52 * Throughout most of the specification this is called the
53 * "Cumulative TSN ACK Point". In this case, we
54 * ignore the advice in 12.2 in favour of the term
55 * used in the bulk of the text.
56 */
57 __u32 cumulative_tsn_ack_point;
58
59 /* This is the highest TSN we've marked. */
60 __u32 max_tsn_seen;
61
62 /* This is the minimum number of TSNs we can track. This corresponds
63 * to the size of tsn_map. Note: the overflow_map allows us to
64 * potentially track more than this quantity.
65 */
66 __u16 len;
67
68 /* Data chunks pending receipt. used by SCTP_STATUS sockopt */
69 __u16 pending_data;
70
71 /* Record duplicate TSNs here. We clear this after
72 * every SACK. Store up to SCTP_MAX_DUP_TSNS worth of
73 * information.
74 */
75 __u16 num_dup_tsns;
76 __be32 dup_tsns[SCTP_MAX_DUP_TSNS];
77};
78
79struct sctp_tsnmap_iter {
80 __u32 start;
81};
82
83/* Initialize a block of memory as a tsnmap. */
84struct sctp_tsnmap *sctp_tsnmap_init(struct sctp_tsnmap *, __u16 len,
85 __u32 initial_tsn, gfp_t gfp);
86
87void sctp_tsnmap_free(struct sctp_tsnmap *map);
88
89/* Test the tracking state of this TSN.
90 * Returns:
91 * 0 if the TSN has not yet been seen
92 * >0 if the TSN has been seen (duplicate)
93 * <0 if the TSN is invalid (too large to track)
94 */
95int sctp_tsnmap_check(const struct sctp_tsnmap *, __u32 tsn);
96
97/* Mark this TSN as seen. */
98int sctp_tsnmap_mark(struct sctp_tsnmap *, __u32 tsn,
99 struct sctp_transport *trans);
100
101/* Mark this TSN and all lower as seen. */
102void sctp_tsnmap_skip(struct sctp_tsnmap *map, __u32 tsn);
103
104/* Retrieve the Cumulative TSN ACK Point. */
105static inline __u32 sctp_tsnmap_get_ctsn(const struct sctp_tsnmap *map)
106{
107 return map->cumulative_tsn_ack_point;
108}
109
110/* Retrieve the highest TSN we've seen. */
111static inline __u32 sctp_tsnmap_get_max_tsn_seen(const struct sctp_tsnmap *map)
112{
113 return map->max_tsn_seen;
114}
115
116/* How many duplicate TSNs are stored? */
117static inline __u16 sctp_tsnmap_num_dups(struct sctp_tsnmap *map)
118{
119 return map->num_dup_tsns;
120}
121
122/* Return pointer to duplicate tsn array as needed by SACK. */
123static inline __be32 *sctp_tsnmap_get_dups(struct sctp_tsnmap *map)
124{
125 map->num_dup_tsns = 0;
126 return map->dup_tsns;
127}
128
129/* How many gap ack blocks do we have recorded? */
130__u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map,
131 struct sctp_gap_ack_block *gabs);
132
133/* Refresh the count on pending data. */
134__u16 sctp_tsnmap_pending(struct sctp_tsnmap *map);
135
136/* Is there a gap in the TSN map? */
137static inline int sctp_tsnmap_has_gap(const struct sctp_tsnmap *map)
138{
139 return map->cumulative_tsn_ack_point != map->max_tsn_seen;
140}
141
142/* Mark a duplicate TSN. Note: limit the storage of duplicate TSN
143 * information.
144 */
145static inline void sctp_tsnmap_mark_dup(struct sctp_tsnmap *map, __u32 tsn)
146{
147 if (map->num_dup_tsns < SCTP_MAX_DUP_TSNS)
148 map->dup_tsns[map->num_dup_tsns++] = htonl(tsn);
149}
150
151/* Renege a TSN that was seen. */
152void sctp_tsnmap_renege(struct sctp_tsnmap *, __u32 tsn);
153
154/* Is there a gap in the TSN map? */
155int sctp_tsnmap_has_gap(const struct sctp_tsnmap *);
156
157#endif /* __sctp_tsnmap_h__ */