1#ifndef _DCCP_FEAT_H
2#define _DCCP_FEAT_H
3/*
4 *  net/dccp/feat.h
5 *
6 *  An implementation of the DCCP protocol
7 *  Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
8 *
9 *	This program is free software; you can redistribute it and/or modify it
10 *	under the terms of the GNU General Public License version 2 as
11 *	published by the Free Software Foundation.
12 */
13
14#include <linux/types.h>
15#include "dccp.h"
16
17static inline int dccp_feat_is_valid_length(u8 type, u8 feature, u8 len)
18{
19	/* sec. 6.1: Confirm has at least length 3,
20	 * sec. 6.2: Change  has at least length 4 */
21	if (len < 3)
22		return 1;
23	if (len < 4  && (type == DCCPO_CHANGE_L || type == DCCPO_CHANGE_R))
24		return 1;
25	return 0;
26}
27
28static inline int dccp_feat_is_reserved(const u8 feat)
29{
30	return (feat > DCCPF_DATA_CHECKSUM &&
31		feat < DCCPF_MIN_CCID_SPECIFIC) ||
32		feat == DCCPF_RESERVED;
33}
34
35/* feature negotiation knows only these four option types (RFC 4340, sec. 6) */
36static inline int dccp_feat_is_valid_type(const u8 optnum)
37{
38	return optnum >= DCCPO_CHANGE_L && optnum <= DCCPO_CONFIRM_R;
39
40}
41
42#ifdef CONFIG_IP_DCCP_DEBUG
43extern const char *dccp_feat_typename(const u8 type);
44extern const char *dccp_feat_name(const u8 feat);
45
46static inline void dccp_feat_debug(const u8 type, const u8 feat, const u8 val)
47{
48	dccp_pr_debug("%s(%s (%d), %d)\n", dccp_feat_typename(type),
49					   dccp_feat_name(feat), feat, val);
50}
51#else
52#define dccp_feat_debug(type, feat, val)
53#endif /* CONFIG_IP_DCCP_DEBUG */
54
55extern int  dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
56			     u8 *val, u8 len, gfp_t gfp);
57extern int  dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature,
58				  u8 *val, u8 len);
59extern int  dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
60				   u8 *val, u8 len);
61extern void dccp_feat_clean(struct dccp_minisock *dmsk);
62extern int  dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
63extern int  dccp_feat_init(struct dccp_minisock *dmsk);
64
65#endif /* _DCCP_FEAT_H */
66