mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-20 08:22:39 +00:00
fade756f18
With this patch, TX/RX CCIDs can now be changed on a per-connection basis, which overrides the defaults set by the global sysctl variables for TX/RX CCIDs. To make full use of this facility, the remaining patches of this patch set are needed, which track dependencies and activate negotiated feature values. Note on the maximum number of CCIDs that can be registered: ----------------------------------------------------------- The maximum number of CCIDs that can be registered on the socket is constrained by the space in a Confirm/Change feature negotiation option. The space in these in turn depends on the size of header options as defined in RFC 4340, 5.8. Since this is a recurring constant, it has been moved from ackvec.h into linux/dccp.h, clarifying its purpose. Relative to this size, the maximum number of CCID identifiers that can be present in a Confirm option (which always consumes 1 byte more than a Change option, cf. 6.1) is 2 bytes less than the maximum TLV size: one for the CCID-feature-type and one for the selected value. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
158 lines
4.2 KiB
C
158 lines
4.2 KiB
C
#ifndef _ACKVEC_H
|
|
#define _ACKVEC_H
|
|
/*
|
|
* net/dccp/ackvec.h
|
|
*
|
|
* An implementation of the DCCP protocol
|
|
* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@mandriva.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/dccp.h>
|
|
#include <linux/compiler.h>
|
|
#include <linux/ktime.h>
|
|
#include <linux/list.h>
|
|
#include <linux/types.h>
|
|
|
|
/* We can spread an ack vector across multiple options */
|
|
#define DCCP_MAX_ACKVEC_LEN (DCCP_SINGLE_OPT_MAXLEN * 2)
|
|
|
|
#define DCCP_ACKVEC_STATE_RECEIVED 0
|
|
#define DCCP_ACKVEC_STATE_ECN_MARKED (1 << 6)
|
|
#define DCCP_ACKVEC_STATE_NOT_RECEIVED (3 << 6)
|
|
|
|
#define DCCP_ACKVEC_STATE_MASK 0xC0 /* 11000000 */
|
|
#define DCCP_ACKVEC_LEN_MASK 0x3F /* 00111111 */
|
|
|
|
/** struct dccp_ackvec - ack vector
|
|
*
|
|
* This data structure is the one defined in RFC 4340, Appendix A.
|
|
*
|
|
* @av_buf_head - circular buffer head
|
|
* @av_buf_tail - circular buffer tail
|
|
* @av_buf_ackno - ack # of the most recent packet acknowledgeable in the
|
|
* buffer (i.e. %av_buf_head)
|
|
* @av_buf_nonce - the one-bit sum of the ECN Nonces on all packets acked
|
|
* by the buffer with State 0
|
|
*
|
|
* Additionally, the HC-Receiver must keep some information about the
|
|
* Ack Vectors it has recently sent. For each packet sent carrying an
|
|
* Ack Vector, it remembers four variables:
|
|
*
|
|
* @av_records - list of dccp_ackvec_record
|
|
* @av_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
|
|
*
|
|
* @av_time - the time in usecs
|
|
* @av_buf - circular buffer of acknowledgeable packets
|
|
*/
|
|
struct dccp_ackvec {
|
|
u64 av_buf_ackno;
|
|
struct list_head av_records;
|
|
ktime_t av_time;
|
|
u16 av_buf_head;
|
|
u16 av_vec_len;
|
|
u8 av_buf_nonce;
|
|
u8 av_ack_nonce;
|
|
u8 av_buf[DCCP_MAX_ACKVEC_LEN];
|
|
};
|
|
|
|
/** struct dccp_ackvec_record - ack vector record
|
|
*
|
|
* ACK vector record as defined in Appendix A of spec.
|
|
*
|
|
* The list is sorted by avr_ack_seqno
|
|
*
|
|
* @avr_node - node in av_records
|
|
* @avr_ack_seqno - sequence number of the packet this record was sent on
|
|
* @avr_ack_ackno - sequence number being acknowledged
|
|
* @avr_ack_ptr - pointer into av_buf where this record starts
|
|
* @avr_ack_nonce - av_ack_nonce at the time this record was sent
|
|
* @avr_sent_len - lenght of the record in av_buf
|
|
*/
|
|
struct dccp_ackvec_record {
|
|
struct list_head avr_node;
|
|
u64 avr_ack_seqno;
|
|
u64 avr_ack_ackno;
|
|
u16 avr_ack_ptr;
|
|
u16 avr_sent_len;
|
|
u8 avr_ack_nonce;
|
|
};
|
|
|
|
struct sock;
|
|
struct sk_buff;
|
|
|
|
#ifdef CONFIG_IP_DCCP_ACKVEC
|
|
extern int dccp_ackvec_init(void);
|
|
extern void dccp_ackvec_exit(void);
|
|
|
|
extern struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority);
|
|
extern void dccp_ackvec_free(struct dccp_ackvec *av);
|
|
|
|
extern int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
|
|
const u64 ackno, const u8 state);
|
|
|
|
extern void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
|
|
struct sock *sk, const u64 ackno);
|
|
extern int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
|
|
u64 *ackno, const u8 opt,
|
|
const u8 *value, const u8 len);
|
|
|
|
extern int dccp_insert_option_ackvec(struct sock *sk, struct sk_buff *skb);
|
|
|
|
static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
|
|
{
|
|
return av->av_vec_len;
|
|
}
|
|
#else /* CONFIG_IP_DCCP_ACKVEC */
|
|
static inline int dccp_ackvec_init(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void dccp_ackvec_exit(void)
|
|
{
|
|
}
|
|
|
|
static inline struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline void dccp_ackvec_free(struct dccp_ackvec *av)
|
|
{
|
|
}
|
|
|
|
static inline int dccp_ackvec_add(struct dccp_ackvec *av, const struct sock *sk,
|
|
const u64 ackno, const u8 state)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
static inline void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec *av,
|
|
struct sock *sk, const u64 ackno)
|
|
{
|
|
}
|
|
|
|
static inline int dccp_ackvec_parse(struct sock *sk, const struct sk_buff *skb,
|
|
const u64 *ackno, const u8 opt,
|
|
const u8 *value, const u8 len)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
static inline int dccp_insert_option_ackvec(const struct sock *sk,
|
|
const struct sk_buff *skb)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_IP_DCCP_ACKVEC */
|
|
#endif /* _ACKVEC_H */
|