LXR linux/net/dccp/feat.h

   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        /* XXX: add per-feature length validation (sec. 6.6.8) */
  26        return 0;
  27}
  28
  29static inline int dccp_feat_is_reserved(const u8 feat)
  30{
  31        return (feat > DCCPF_DATA_CHECKSUM &&
  32                feat < DCCPF_MIN_CCID_SPECIFIC) ||
  33                feat == DCCPF_RESERVED;
  34}
  35
  36/* feature negotiation knows only these four option types (RFC 4340, sec. 6) */
  37static inline int dccp_feat_is_valid_type(const u8 optnum)
  38{
  39        return optnum >= DCCPO_CHANGE_L && optnum <= DCCPO_CONFIRM_R;
  40
  41}
  42
  43#ifdef CONFIG_IP_DCCP_DEBUG
  44extern const char *dccp_feat_typename(const u8 type);
  45extern const char *dccp_feat_name(const u8 feat);
  46
  47static inline void dccp_feat_debug(const u8 type, const u8 feat, const u8 val)
  48{
  49        dccp_pr_debug("%s(%s (%d), %d)\n", dccp_feat_typename(type),
  50                                           dccp_feat_name(feat), feat, val);
  51}
  52#else
  53#define dccp_feat_debug(type, feat, val)
  54#endif /* CONFIG_IP_DCCP_DEBUG */
  55
  56extern int  dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
  57                             u8 *val, u8 len, gfp_t gfp);
  58extern int  dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature,
  59                                  u8 *val, u8 len);
  60extern int  dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
  61                                   u8 *val, u8 len);
  62extern void dccp_feat_clean(struct dccp_minisock *dmsk);
  63extern int  dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
  64extern int  dccp_feat_init(struct dccp_minisock *dmsk);
  65
  66#endif /* _DCCP_FEAT_H */
  67