#ifndef _DCCP_H
#define _DCCP_H
/*
* net/dccp/dccp.h
*
* An implementation of the DCCP protocol
* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* 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 <net/snmp.h>
#include <net/sock.h>
#include <net/tcp.h>
#define DCCP_DEBUG
#ifdef DCCP_DEBUG
extern int dccp_debug;
#define dccp_pr_debug(format, a...) \
do { if (dccp_debug) \
printk(KERN_DEBUG "%s: " format, __FUNCTION__ , ##a); \
} while (0)
#define dccp_pr_debug_cat(format, a...) do { if (dccp_debug) printk(format, ##a); } while (0)
#else
#define dccp_pr_debug(format, a...)
#define dccp_pr_debug_cat(format, a...)
#endif
extern struct inet_hashinfo dccp_hashinfo;
extern atomic_t dccp_orphan_count;
extern int dccp_tw_count;
extern void dccp_tw_deschedule(struct inet_timewait_sock *tw);
extern void dccp_time_wait(struct sock *sk, int state, int timeo);
/* FIXME: Right size this */
#define DCCP_MAX_OPT_LEN 128
#define DCCP_MAX_PACKET_HDR 32
#define MAX_DCCP_HEADER (DCCP_MAX_PACKET_HDR + DCCP_MAX_OPT_LEN + MAX_HEADER)
#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
* state, about 60 seconds */
/* draft-ietf-dccp-spec-11.txt initial RTO value */
#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))
/* Maximal interval between probes for local resources. */
#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))
#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */
extern struct proto dccp_v4_prot;
/* is seq1 < seq2 ? */
static inline const int before48(const u64 seq1, const u64 seq2)
{
return (const s64)((seq1 << 16) - (seq2 << 16)) < 0;
}
/* is seq1 > seq2 ? */
static inline const int after48(const u64 seq1, const u64 seq2)
{
return (const s64)((seq2 << 16) - (seq1 << 16)) < 0;
}
/* is seq2 <= seq1 <= seq3 ? */
static inline const int between48(const u64 seq1, const u64 seq2, const u64 seq3)
{
return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16);
}
static inline u64 max48(const u64 seq1, const u64 seq2)
{
return after48(seq1, seq2) ? seq1 : seq2;
}
enum {
DCCP_MIB_NUM = 0,
DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */
DCCP_MIB_ESTABRESETS, /* EstabResets */
DCCP_MIB_CURRESTAB, /* CurrEstab */
DCCP_MIB_OUTSEGS, /* OutSegs */
DCCP_MIB_OUTRSTS,
DCCP_MIB_ABORTONTIMEOUT,
DCCP_MIB_TIMEOUTS,
DCCP_MIB_ABORTFAILED,
DCCP_MIB_PASSIVEOPENS,
DCCP_MIB_ATTEMPTFAILS,
DCCP_MIB_OUTDATAGRAMS,
DCCP_MIB_INERRS,
DCCP_MIB_OPTMANDATORYERROR,
DCCP_MIB_INVALIDOPT,
__DCCP_MIB_MAX
};
#define DCCP_MIB_MAX __DCCP_MIB_MAX
struct dccp_mib {
unsigned long mibs[DCCP_MIB_MAX];
} __SNMP_MIB_ALIGN__;
DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics);
#define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field)
#define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field)
#define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field)
#define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field)
#define DCCP_ADD_STATS_BH(field, val) SNMP_ADD_STATS_BH(dccp_statistics, field, val)
#define DCCP_ADD_STATS_USER(field, val) SNMP_ADD_STATS_USER(dccp_statistics, field, val)
extern int dccp_transmit_skb(struct sock *sk, struct sk_buff *skb);
extern int dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb);
extern int dccp_send_response(struct sock *sk);
extern void dccp_send_ack(struct sock *sk);
extern void dccp_send_delayed_ack(struct sock *sk);
extern void dccp_send_sync(struct sock *sk, u64 seq);
extern int dccp_write_xmit(struct sock *sk, struct sk_buff *skb,
const int len);
extern void dccp_init_xmit_timers(struct sock *sk);
static inline void dccp_clear_xmit_timers(struct sock *sk)
{
inet_csk_clear_xmit_timers(sk);
}
extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu);
extern const char *dccp_packet_name(const int type);
extern const char *dccp_state_name(const int state);
static inline void dccp_set_state(struct sock *sk, const int state)
{
const int oldstate = sk->sk_state;
dccp_pr_debug("%s(%p) %-10.10s -> %s\n",
dccp_role(sk), sk,
dccp_state_name(oldstate), dccp_state_name(state));
WARN_ON(state == oldstate);
switch (state) {
case DCCP_OPEN:
if (oldstate != DCCP_OPEN)
DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
break;
case DCCP_CLOSED:
if (oldstate == DCCP_CLOSING || oldstate == DCCP_OPEN)
DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
sk->sk_prot->unhash(sk);
if (inet_csk(sk)->icsk_bind_hash != NULL &&
!(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
inet_put_port(&dccp_hashinfo, sk);
/* fall through */
default:
if (oldstate == DCCP_OPEN)
DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
}
/* Change state AFTER socket is unhashed to avoid closed
* socket sitting in hash tables.
*/
sk->sk_state = state;
}
static inline void dccp_done(struct sock *sk)
{
dccp_set_state(sk, DCCP_CLOSED);
dccp_clear_xmit_timers(sk);
sk->sk_shutdown = SHUTDOWN_MASK;
if (!sock_flag(sk, SOCK_DEAD))
sk->sk_state_change(sk);
else
inet_csk_destroy_sock(sk);
}
static inline void dccp_openreq_init(struct request_sock *req,
struct dccp_sock *dp,
struct sk_buff *skb)
{
/*
* FIXME: fill in the other req fields from the DCCP options
* received
*/
inet_rsk(req)->rmt_port = dccp_hdr(skb)->dccph_sport;
inet_rsk(req)->acked = 0;
req->rcv_wnd = 0;
}
extern int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb);
extern struct sock *dccp_create_openreq_child(struct sock *sk,
const struct request_sock *req,
const struct sk_buff *skb);
extern int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb);
extern void dccp_v4_err(struct sk_buff *skb, u32);
extern int dccp_v4_rcv(struct sk_buff *skb);
extern struct sock *dccp_v4_request_recv_sock(struct sock *sk,
struct sk_buff *skb,
struct request_sock *req,
struct dst_entry *dst);
extern struct sock *dccp_check_req(struct sock *sk, struct sk_buff *skb,
struct request_sock *req,
struct request_sock **prev);
extern int dccp_child_process(struct sock *parent, struct sock *child,
struct sk_buff *skb);
extern int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
struct dccp_hdr *dh, unsigned len);
extern int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
const struct dccp_hdr *dh, const unsigned len);
extern void dccp_close(struct sock *sk, long timeout);
extern struct sk_buff *dccp_make_response(struct sock *sk,
struct dst_entry *dst,
struct request_sock *req);
extern int dccp_connect(struct sock *sk);
extern int dccp_disconnect(struct sock *sk, int flags);
extern int dccp_getsockopt(struct sock *sk, int level, int optname,
char *optval, int *optlen);
extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg);
extern int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
size_t size);
extern int dccp_recvmsg(struct kiocb *iocb, struct sock *sk,
struct msghdr *msg, size_t len, int nonblock,
int flags, int *addr_len);
extern int dccp_setsockopt(struct sock *sk, int level, int optname,
char *optval, int optlen);
extern void dccp_shutdown(struct sock *sk, int how);
extern int dccp_v4_checksum(const struct sk_buff *skb,
const u32 saddr, const u32 daddr);
extern int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code);
extern void dccp_send_close(struct sock *sk);
struct dccp_skb_cb {
__u8 dccpd_type;
__u8 dccpd_reset_code;
__u8 dccpd_service;
__u8 dccpd_ccval;
__u64 dccpd_seq;
__u64 dccpd_ack_seq;
int dccpd_opt_len;
};
#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
static inline int dccp_non_data_packet(const struct sk_buff *skb)
{
const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
return type == DCCP_PKT_ACK ||
type == DCCP_PKT_CLOSE ||
type == DCCP_PKT_CLOSEREQ ||
type == DCCP_PKT_RESET ||
type == DCCP_PKT_SYNC ||
type == DCCP_PKT_SYNCACK;
}
static inline int dccp_packet_without_ack(const struct sk_buff *skb)
{
const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
return type == DCCP_PKT_DATA || type == DCCP_PKT_REQUEST;
}
#define DCCP_MAX_SEQNO ((((u64)1) << 48) - 1)
#define DCCP_PKT_WITHOUT_ACK_SEQ (DCCP_MAX_SEQNO << 2)
static inline void dccp_set_seqno(u64 *seqno, u64 value)
{
if (value > DCCP_MAX_SEQNO)
value -= DCCP_MAX_SEQNO + 1;
*seqno = value;
}
static inline u64 dccp_delta_seqno(u64 seqno1, u64 seqno2)
{
return ((seqno2 << 16) - (seqno1 << 16)) >> 16;
}
static inline void dccp_inc_seqno(u64 *seqno)
{
if (++*seqno > DCCP_MAX_SEQNO)
*seqno = 0;
}
static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
{
struct dccp_hdr_ext *dhx = (struct dccp_hdr_ext *)((void *)dh + sizeof(*dh));
#if defined(__LITTLE_ENDIAN_BITFIELD)
dh->dccph_seq = htonl((gss >> 32)) >> 8;
#elif defined(__BIG_ENDIAN_BITFIELD)
dh->dccph_seq = htonl((gss >> 32));
#else
#error "Adjust your <asm/byteorder.h> defines"
#endif
dhx->dccph_seq_low = htonl(gss & 0xffffffff);
}
static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack, const u64 gsr)
{
#if defined(__LITTLE_ENDIAN_BITFIELD)
dhack->dccph_ack_nr_high = htonl((gsr >> 32)) >> 8;
#elif defined(__BIG_ENDIAN_BITFIELD)
dhack->dccph_ack_nr_high = htonl((gsr >> 32));
#else
#error "Adjust your <asm/byteorder.h> defines"
#endif
dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff);
}
static inline void dccp_update_gsr(struct sock *sk, u64 seq)
{
struct dccp_sock *dp = dccp_sk(sk);
u64 tmp_gsr;
dccp_set_seqno(&tmp_gsr, dp->dccps_gsr + 1 - (dp->dccps_options.dccpo_sequence_window / 4));
dp->dccps_gsr = seq;
dccp_set_seqno(&dp->dccps_swl, max48(tmp_gsr, dp->dccps_isr));
dccp_set_seqno(&dp->dccps_swh,
dp->dccps_gsr + (3 * dp->dccps_options.dccpo_sequence_window) / 4);
}
static inline void dccp_update_gss(struct sock *sk, u64 seq)
{
struct dccp_sock *dp = dccp_sk(sk);
u64 tmp_gss;
dccp_set_seqno(&tmp_gss, dp->dccps_gss - dp->dccps_options.dccpo_sequence_window + 1);
dp->dccps_awl = max48(tmp_gss, dp->dccps_iss);
dp->dccps_awh = dp->dccps_gss = seq;
}
extern void dccp_insert_options(struct sock *sk, struct sk_buff *skb);
extern void dccp_insert_option_elapsed_time(struct sock *sk,
struct sk_buff *skb,
u32 elapsed_time);
extern void dccp_insert_option(struct sock *sk, struct sk_buff *skb,
unsigned char option,
const void *value, unsigned char len);
extern struct socket *dccp_ctl_socket;
#define DCCP_ACKPKTS_STATE_RECEIVED 0
#define DCCP_ACKPKTS_STATE_ECN_MARKED (1 << 6)
#define DCCP_ACKPKTS_STATE_NOT_RECEIVED (3 << 6)
#define DCCP_ACKPKTS_STATE_MASK 0xC0 /* 11000000 */
#define DCCP_ACKPKTS_LEN_MASK 0x3F /* 00111111 */
/** struct dccp_ackpkts - acknowledgeable packets
*
* This data structure is the one defined in the DCCP draft
* Appendix A.
*
* @dccpap_buf_head - circular buffer head
* @dccpap_buf_tail - circular buffer tail
* @dccpap_buf_ackno - ack # of the most recent packet acknoldgeable in the buffer (i.e. %dccpap_buf_head)
* @dccpap_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:
*
* @dccpap_ack_seqno - the Sequence Number used for the packet (HC-Receiver seqno)
* @dccpap_ack_ptr - the value of buf_head at the time of acknowledgement.
* @dccpap_ack_ackno - the Acknowledgement Number used for the packet (HC-Sender seqno)
* @dccpap_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
*
* @dccpap_buf_len - circular buffer length
* @dccpap_buf - circular buffer of acknowledgeable packets
*/
struct dccp_ackpkts {
unsigned int dccpap_buf_head;
unsigned int dccpap_buf_tail;
u64 dccpap_buf_ackno;
u64 dccpap_ack_seqno;
u64 dccpap_ack_ackno;
unsigned int dccpap_ack_ptr;
unsigned int dccpap_buf_vector_len;
unsigned int dccpap_ack_vector_len;
unsigned int dccpap_buf_len;
unsigned long dccpap_time;
u8 dccpap_buf_nonce;
u8 dccpap_ack_nonce;
u8 dccpap_buf[0];
};
extern struct dccp_ackpkts *dccp_ackpkts_alloc(unsigned int len, int priority);
extern void dccp_ackpkts_free(struct dccp_ackpkts *ap);
extern int dccp_ackpkts_add(struct dccp_ackpkts *ap, u64 ackno, u8 state);
extern void dccp_ackpkts_check_rcv_ackno(struct dccp_ackpkts *ap,
struct sock *sk, u64 ackno);
#ifdef DCCP_DEBUG
extern void dccp_ackvector_print(const u64 ackno,
const unsigned char *vector, int len);
extern void dccp_ackpkts_print(const struct dccp_ackpkts *ap);
#else
static inline void dccp_ackvector_print(const u64 ackno,
const unsigned char *vector,
int len) { }
static inline void dccp_ackpkts_print(const struct dccp_ackpkts *ap) { }
#endif
#endif /* _DCCP_H */
