[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / dccp / dccp.h

#ifndef _DCCP_H
#define _DCCP_H
/*
 *  net/dccp/dccp.h
 *
 *  An implementation of the DCCP protocol
 *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 *  Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz>
 *
 *	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>
#include "ackvec.h"

/*
 * 	DCCP - specific warning and debugging macros.
 */
#define DCCP_WARN(fmt, a...) LIMIT_NETDEBUG(KERN_WARNING "%s: " fmt,       \
							__FUNCTION__, ##a)
#define DCCP_CRIT(fmt, a...) printk(KERN_CRIT fmt " at %s:%d/%s()\n", ##a, \
					 __FILE__, __LINE__, __FUNCTION__)
#define DCCP_BUG(a...)       do { DCCP_CRIT("BUG: " a); dump_stack(); } while(0)
#define DCCP_BUG_ON(cond)    do { if (unlikely((cond) != 0))		   \
				     DCCP_BUG("\"%s\" holds (exception!)", \
					      __stringify(cond));          \
			     } while (0)

#define DCCP_PRINTK(enable, fmt, args...)	do { if (enable)	     \
							printk(fmt, ##args); \
						} while(0)
#define DCCP_PR_DEBUG(enable, fmt, a...)	DCCP_PRINTK(enable, KERN_DEBUG \
						  "%s: " fmt, __FUNCTION__, ##a)

#ifdef CONFIG_IP_DCCP_DEBUG
extern int dccp_debug;
#define dccp_pr_debug(format, a...)	  DCCP_PR_DEBUG(dccp_debug, format, ##a)
#define dccp_pr_debug_cat(format, a...)   DCCP_PRINTK(dccp_debug, format, ##a)
#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 void dccp_time_wait(struct sock *sk, int state, int timeo);

/*
 *  Set safe upper bounds for header and option length. Since Data Offset is 8
 *  bits (RFC 4340, sec. 5.1), the total header length can never be more than
 *  4 * 255 = 1020 bytes. The largest possible header length is 28 bytes (X=1):
 *    - DCCP-Response with ACK Subheader and 4 bytes of Service code      OR
 *    - DCCP-Reset    with ACK Subheader and 4 bytes of Reset Code fields
 *  Hence a safe upper bound for the maximum option length is 1020-28 = 992
 */
#define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(int))
#define DCCP_MAX_PACKET_HDR 28
#define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR)
#define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER)

#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
				     * state, about 60 seconds */

/* RFC 1122, 4.2.3.1 initial RTO value */
#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))

#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */

/* bounds for sampled RTT values from packet exchanges (in usec) */
#define DCCP_SANE_RTT_MIN	100
#define DCCP_SANE_RTT_MAX	(4 * USEC_PER_SEC)

/* Maximal interval between probes for local resources.  */
#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))

/* sysctl variables for DCCP */
extern int  sysctl_dccp_request_retries;
extern int  sysctl_dccp_retries1;
extern int  sysctl_dccp_retries2;
extern int  sysctl_dccp_feat_sequence_window;
extern int  sysctl_dccp_feat_rx_ccid;
extern int  sysctl_dccp_feat_tx_ccid;
extern int  sysctl_dccp_feat_ack_ratio;
extern int  sysctl_dccp_feat_send_ack_vector;
extern int  sysctl_dccp_feat_send_ndp_count;
extern int  sysctl_dccp_tx_qlen;

/*
 *	48-bit sequence number arithmetic (signed and unsigned)
 */
#define INT48_MIN	  0x800000000000LL		/* 2^47	    */
#define UINT48_MAX	  0xFFFFFFFFFFFFLL		/* 2^48 - 1 */
#define COMPLEMENT48(x)	 (0x1000000000000LL - (x))	/* 2^48 - x */
#define TO_SIGNED48(x)	 (((x) < INT48_MIN)? (x) : -COMPLEMENT48( (x)))
#define TO_UNSIGNED48(x) (((x) >= 0)?	     (x) :  COMPLEMENT48(-(x)))
#define ADD48(a, b)	 (((a) + (b)) & UINT48_MAX)
#define SUB48(a, b)	 ADD48((a), COMPLEMENT48(b))

static inline void dccp_set_seqno(u64 *seqno, u64 value)
{
	*seqno = value & UINT48_MAX;
}

static inline void dccp_inc_seqno(u64 *seqno)
{
	*seqno = ADD48(*seqno, 1);
}

/* signed mod-2^48 distance: pos. if seqno1 < seqno2, neg. if seqno1 > seqno2 */
static inline s64 dccp_delta_seqno(const u64 seqno1, const u64 seqno2)
{
	u64 delta = SUB48(seqno2, seqno1);

	return TO_SIGNED48(delta);
}

/* is seq1 < seq2 ? */
static inline int before48(const u64 seq1, const u64 seq2)
{
	return (s64)((seq2 << 16) - (seq1 << 16)) > 0;
}

/* is seq1 > seq2 ? */
#define after48(seq1, seq2)	before48(seq2, seq1)

/* is seq2 <= seq1 <= seq3 ? */
static inline 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;
}

/* is seq1 next seqno after seq2 */
static inline int follows48(const u64 seq1, const u64 seq2)
{
	return dccp_delta_seqno(seq2, seq1) == 1;
}

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)

/*
 * 	Checksumming routines
 */
static inline unsigned int dccp_csum_coverage(const struct sk_buff *skb)
{
	const struct dccp_hdr* dh = dccp_hdr(skb);

	if (dh->dccph_cscov == 0)
		return skb->len;
	return (dh->dccph_doff + dh->dccph_cscov - 1) * sizeof(u32);
}

static inline void dccp_csum_outgoing(struct sk_buff *skb)
{
	unsigned int cov = dccp_csum_coverage(skb);

	if (cov >= skb->len)
		dccp_hdr(skb)->dccph_cscov = 0;

	skb->csum = skb_checksum(skb, 0, (cov > skb->len)? skb->len : cov, 0);
}

extern void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb);

extern int  dccp_retransmit_skb(struct sock *sk, struct sk_buff *skb);

extern void dccp_send_ack(struct sock *sk);
extern void dccp_send_delayed_ack(struct sock *sk);
extern void dccp_reqsk_send_ack(struct sk_buff *sk, struct request_sock *rsk);

extern void dccp_send_sync(struct sock *sk, const u64 seq,
			   const enum dccp_pkt_type pkt_type);

extern void dccp_write_xmit(struct sock *sk, int block);
extern void dccp_write_space(struct sock *sk);

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);

extern void dccp_set_state(struct sock *sk, const int state);
extern void dccp_done(struct sock *sk);

extern void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb);

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 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 int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized);
extern int dccp_destroy_sock(struct sock *sk);

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 void	   dccp_hash(struct sock *sk);
extern void	   dccp_unhash(struct sock *sk);
extern int	   dccp_getsockopt(struct sock *sk, int level, int optname,
				   char __user *optval, int __user *optlen);
extern int	   dccp_setsockopt(struct sock *sk, int level, int optname,
				   char __user *optval, int optlen);
#ifdef CONFIG_COMPAT
extern int	   compat_dccp_getsockopt(struct sock *sk,
				int level, int optname,
				char __user *optval, int __user *optlen);
extern int	   compat_dccp_setsockopt(struct sock *sk,
				int level, int optname,
				char __user *optval, int optlen);
#endif
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 void	   dccp_shutdown(struct sock *sk, int how);
extern int	   inet_dccp_listen(struct socket *sock, int backlog);
extern unsigned int dccp_poll(struct file *file, struct socket *sock,
			     poll_table *wait);
extern int	   dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr,
				   int addr_len);

extern int	   dccp_send_reset(struct sock *sk, enum dccp_reset_codes code);
extern void	   dccp_send_close(struct sock *sk, const int active);
extern int	   dccp_invalid_packet(struct sk_buff *skb);
extern u32	   dccp_sample_rtt(struct sock *sk, struct timeval *t_recv,
						    struct timeval *t_history);

static inline int dccp_bad_service_code(const struct sock *sk,
					const __be32 service)
{
	const struct dccp_sock *dp = dccp_sk(sk);

	if (dp->dccps_service == service)
		return 0;
	return !dccp_list_has_service(dp->dccps_service_list, service);
}

struct dccp_skb_cb {
	__u8  dccpd_type:4;
	__u8  dccpd_ccval:4;
	__u8  dccpd_reset_code;
	__u16 dccpd_opt_len;
	__u64 dccpd_seq;
	__u64 dccpd_ack_seq;
};

#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_PKT_WITHOUT_ACK_SEQ (UINT48_MAX << 2)

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));
	dh->dccph_seq2 = 0;
	dh->dccph_seq = htons((gss >> 32) & 0xfffff);
	dhx->dccph_seq_low = htonl(gss & 0xffffffff);
}

static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack,
				    const u64 gsr)
{
	dhack->dccph_reserved1 = 0;
	dhack->dccph_ack_nr_high = htons(gsr >> 32);
	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);
	const struct dccp_minisock *dmsk = dccp_msk(sk);

	dp->dccps_gsr = seq;
	dccp_set_seqno(&dp->dccps_swl,
		       dp->dccps_gsr + 1 - (dmsk->dccpms_sequence_window / 4));
	dccp_set_seqno(&dp->dccps_swh,
		       dp->dccps_gsr + (3 * dmsk->dccpms_sequence_window) / 4);
}

static inline void dccp_update_gss(struct sock *sk, u64 seq)
{
	struct dccp_sock *dp = dccp_sk(sk);

	dp->dccps_awh = dp->dccps_gss = seq;
	dccp_set_seqno(&dp->dccps_awl,
		       (dp->dccps_gss -
			dccp_msk(sk)->dccpms_sequence_window + 1));
}

static inline int dccp_ack_pending(const struct sock *sk)
{
	const struct dccp_sock *dp = dccp_sk(sk);
	return dp->dccps_timestamp_echo != 0 ||
#ifdef CONFIG_IP_DCCP_ACKVEC
	       (dccp_msk(sk)->dccpms_send_ack_vector &&
		dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) ||
#endif
	       inet_csk_ack_scheduled(sk);
}

extern int dccp_insert_options(struct sock *sk, struct sk_buff *skb);
extern int dccp_insert_option_elapsed_time(struct sock *sk,
					    struct sk_buff *skb,
					    u32 elapsed_time);
extern int dccp_insert_option_timestamp(struct sock *sk,
					 struct sk_buff *skb);
extern int dccp_insert_option(struct sock *sk, struct sk_buff *skb,
			       unsigned char option,
			       const void *value, unsigned char len);

extern void dccp_timestamp(const struct sock *sk, struct timeval *tv);

static inline suseconds_t timeval_usecs(const struct timeval *tv)
{
	return tv->tv_sec * USEC_PER_SEC + tv->tv_usec;
}

static inline suseconds_t timeval_delta(const struct timeval *large,
					const struct timeval *small)
{
	time_t	    secs  = large->tv_sec  - small->tv_sec;
	suseconds_t usecs = large->tv_usec - small->tv_usec;

	if (usecs < 0) {
		secs--;
		usecs += USEC_PER_SEC;
	}
	return secs * USEC_PER_SEC + usecs;
}

static inline void timeval_add_usecs(struct timeval *tv,
				     const suseconds_t usecs)
{
	tv->tv_usec += usecs;
	while (tv->tv_usec >= USEC_PER_SEC) {
		tv->tv_sec++;
		tv->tv_usec -= USEC_PER_SEC;
	}
}

static inline void timeval_sub_usecs(struct timeval *tv,
				     const suseconds_t usecs)
{
	tv->tv_usec -= usecs;
	while (tv->tv_usec < 0) {
		tv->tv_sec--;
		tv->tv_usec += USEC_PER_SEC;
	}
	DCCP_BUG_ON(tv->tv_sec < 0);
}

#ifdef CONFIG_SYSCTL
extern int dccp_sysctl_init(void);
extern void dccp_sysctl_exit(void);
#else
static inline int dccp_sysctl_init(void)
{
	return 0;
}

static inline void dccp_sysctl_exit(void)
{
}
#endif

#endif /* _DCCP_H */
Commit	Line	Data
7c657876 ACM	1	#ifndef _DCCP_H
	2	#define _DCCP_H
	3	/*
	4	* net/dccp/dccp.h
	5	*
	6	* An implementation of the DCCP protocol
1bc09869	7	* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
e6bccd35	8	* Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz>
7c657876 ACM	9	*
	10	* This program is free software; you can redistribute it and/or modify it
	11	* under the terms of the GNU General Public License version 2 as
	12	* published by the Free Software Foundation.
	13	*/
	14
	15	#include <linux/dccp.h>
	16	#include <net/snmp.h>
	17	#include <net/sock.h>
	18	#include <net/tcp.h>
ae31c339	19	#include "ackvec.h"
7c657876	20
59348b19 GR	21	/*
	22	* DCCP - specific warning and debugging macros.
	23	*/
	24	#define DCCP_WARN(fmt, a...) LIMIT_NETDEBUG(KERN_WARNING "%s: " fmt, \
c9eaf173	25	__FUNCTION__, ##a)
59348b19 GR	26	#define DCCP_CRIT(fmt, a...) printk(KERN_CRIT fmt " at %s:%d/%s()\n", ##a, \
	27	__FILE__, __LINE__, __FUNCTION__)
	28	#define DCCP_BUG(a...) do { DCCP_CRIT("BUG: " a); dump_stack(); } while(0)
	29	#define DCCP_BUG_ON(cond) do { if (unlikely((cond) != 0)) \
	30	DCCP_BUG("\"%s\" holds (exception!)", \
	31	__stringify(cond)); \
3c695262 GR	32	} while (0)
3c695262 GR	33
84116716 GR	34	#define DCCP_PRINTK(enable, fmt, args...) do { if (enable) \
84116716 GR	35	printk(fmt, ##args); \
c9eaf173	36	} while(0)
84116716 GR	37	#define DCCP_PR_DEBUG(enable, fmt, a...) DCCP_PRINTK(enable, KERN_DEBUG \
	38	"%s: " fmt, __FUNCTION__, ##a)
	39
725ba8ee	40	#ifdef CONFIG_IP_DCCP_DEBUG
7c657876	41	extern int dccp_debug;
84116716 GR	42	#define dccp_pr_debug(format, a...) DCCP_PR_DEBUG(dccp_debug, format, ##a)
84116716 GR	43	#define dccp_pr_debug_cat(format, a...) DCCP_PRINTK(dccp_debug, format, ##a)
7c657876 ACM	44	#else
	45	#define dccp_pr_debug(format, a...)
	46	#define dccp_pr_debug_cat(format, a...)
	47	#endif
	48
	49	extern struct inet_hashinfo dccp_hashinfo;
	50
	51	extern atomic_t dccp_orphan_count;
7c657876 ACM	52
	53	extern void dccp_time_wait(struct sock *sk, int state, int timeo);
	54
60361be1 GR	55	/*
	56	* Set safe upper bounds for header and option length. Since Data Offset is 8
	57	* bits (RFC 4340, sec. 5.1), the total header length can never be more than
	58	* 4 * 255 = 1020 bytes. The largest possible header length is 28 bytes (X=1):
	59	* - DCCP-Response with ACK Subheader and 4 bytes of Service code OR
	60	* - DCCP-Reset with ACK Subheader and 4 bytes of Reset Code fields
	61	* Hence a safe upper bound for the maximum option length is 1020-28 = 992
	62	*/
	63	#define MAX_DCCP_SPECIFIC_HEADER (255 * sizeof(int))
	64	#define DCCP_MAX_PACKET_HDR 28
	65	#define DCCP_MAX_OPT_LEN (MAX_DCCP_SPECIFIC_HEADER - DCCP_MAX_PACKET_HDR)
	66	#define MAX_DCCP_HEADER (MAX_DCCP_SPECIFIC_HEADER + MAX_HEADER)
7c657876 ACM	67
	68	#define DCCP_TIMEWAIT_LEN (60 * HZ) /* how long to wait to destroy TIME-WAIT
	69	* state, about 60 seconds */
	70
0e64e94e	71	/* RFC 1122, 4.2.3.1 initial RTO value */
7c657876 ACM	72	#define DCCP_TIMEOUT_INIT ((unsigned)(3 * HZ))
7c657876 ACM	73
4712a792 GR	74	#define DCCP_RTO_MAX ((unsigned)(120 * HZ)) /* FIXME: using TCP value */
	75
	76	/* bounds for sampled RTT values from packet exchanges (in usec) */
	77	#define DCCP_SANE_RTT_MIN 100
	78	#define DCCP_SANE_RTT_MAX (4 * USEC_PER_SEC)
	79
7c657876 ACM	80	/* Maximal interval between probes for local resources. */
	81	#define DCCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ / 2U))
	82
2e2e9e92 GR	83	/* sysctl variables for DCCP */
	84	extern int sysctl_dccp_request_retries;
	85	extern int sysctl_dccp_retries1;
	86	extern int sysctl_dccp_retries2;
afb0a34d GR	87	extern int sysctl_dccp_feat_sequence_window;
	88	extern int sysctl_dccp_feat_rx_ccid;
	89	extern int sysctl_dccp_feat_tx_ccid;
	90	extern int sysctl_dccp_feat_ack_ratio;
	91	extern int sysctl_dccp_feat_send_ack_vector;
	92	extern int sysctl_dccp_feat_send_ndp_count;
b1308dc0	93	extern int sysctl_dccp_tx_qlen;
2e2e9e92	94
6b811d43 GR	95	/*
	96	* 48-bit sequence number arithmetic (signed and unsigned)
	97	*/
	98	#define INT48_MIN 0x800000000000LL /* 2^47 */
	99	#define UINT48_MAX 0xFFFFFFFFFFFFLL /* 2^48 - 1 */
	100	#define COMPLEMENT48(x) (0x1000000000000LL - (x)) /* 2^48 - x */
	101	#define TO_SIGNED48(x) (((x) < INT48_MIN)? (x) : -COMPLEMENT48( (x)))
	102	#define TO_UNSIGNED48(x) (((x) >= 0)? (x) : COMPLEMENT48(-(x)))
	103	#define ADD48(a, b) (((a) + (b)) & UINT48_MAX)
	104	#define SUB48(a, b) ADD48((a), COMPLEMENT48(b))
	105
	106	static inline void dccp_set_seqno(u64 *seqno, u64 value)
	107	{
	108	*seqno = value & UINT48_MAX;
	109	}
	110
	111	static inline void dccp_inc_seqno(u64 *seqno)
	112	{
	113	seqno = ADD48(seqno, 1);
	114	}
	115
0aec51c8 GR	116	/* signed mod-2^48 distance: pos. if seqno1 < seqno2, neg. if seqno1 > seqno2 */
0aec51c8 GR	117	static inline s64 dccp_delta_seqno(const u64 seqno1, const u64 seqno2)
6b811d43	118	{
0aec51c8 GR	119	u64 delta = SUB48(seqno2, seqno1);
	120
	121	return TO_SIGNED48(delta);
6b811d43 GR	122	}
6b811d43 GR	123
7c657876	124	/* is seq1 < seq2 ? */
a10cedd4	125	static inline int before48(const u64 seq1, const u64 seq2)
7c657876	126	{
d52de17b	127	return (s64)((seq2 << 16) - (seq1 << 16)) > 0;
7c657876 ACM	128	}
	129
	130	/* is seq1 > seq2 ? */
d52de17b	131	#define after48(seq1, seq2) before48(seq2, seq1)
7c657876 ACM	132
7c657876 ACM	133	/* is seq2 <= seq1 <= seq3 ? */
a10cedd4	134	static inline int between48(const u64 seq1, const u64 seq2, const u64 seq3)
7c657876 ACM	135	{
	136	return (seq3 << 16) - (seq2 << 16) >= (seq1 << 16) - (seq2 << 16);
	137	}
	138
	139	static inline u64 max48(const u64 seq1, const u64 seq2)
	140	{
	141	return after48(seq1, seq2) ? seq1 : seq2;
	142	}
	143
837d107c IM	144	/* is seq1 next seqno after seq2 */
	145	static inline int follows48(const u64 seq1, const u64 seq2)
	146	{
b16be51b	147	return dccp_delta_seqno(seq2, seq1) == 1;
837d107c IM	148	}
837d107c IM	149
7c657876 ACM	150	enum {
	151	DCCP_MIB_NUM = 0,
	152	DCCP_MIB_ACTIVEOPENS, /* ActiveOpens */
	153	DCCP_MIB_ESTABRESETS, /* EstabResets */
	154	DCCP_MIB_CURRESTAB, /* CurrEstab */
c9eaf173	155	DCCP_MIB_OUTSEGS, /* OutSegs */
7c657876 ACM	156	DCCP_MIB_OUTRSTS,
	157	DCCP_MIB_ABORTONTIMEOUT,
	158	DCCP_MIB_TIMEOUTS,
	159	DCCP_MIB_ABORTFAILED,
	160	DCCP_MIB_PASSIVEOPENS,
	161	DCCP_MIB_ATTEMPTFAILS,
	162	DCCP_MIB_OUTDATAGRAMS,
	163	DCCP_MIB_INERRS,
	164	DCCP_MIB_OPTMANDATORYERROR,
	165	DCCP_MIB_INVALIDOPT,
	166	__DCCP_MIB_MAX
	167	};
	168
	169	#define DCCP_MIB_MAX __DCCP_MIB_MAX
	170	struct dccp_mib {
	171	unsigned long mibs[DCCP_MIB_MAX];
	172	} __SNMP_MIB_ALIGN__;
	173
	174	DECLARE_SNMP_STAT(struct dccp_mib, dccp_statistics);
7690af3f ACM	175	#define DCCP_INC_STATS(field) SNMP_INC_STATS(dccp_statistics, field)
	176	#define DCCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(dccp_statistics, field)
	177	#define DCCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(dccp_statistics, field)
	178	#define DCCP_DEC_STATS(field) SNMP_DEC_STATS(dccp_statistics, field)
	179	#define DCCP_ADD_STATS_BH(field, val) \
	180	SNMP_ADD_STATS_BH(dccp_statistics, field, val)
	181	#define DCCP_ADD_STATS_USER(field, val) \
	182	SNMP_ADD_STATS_USER(dccp_statistics, field, val)
7c657876	183
6f4e5fff GR	184	/*
	185	* Checksumming routines
	186	*/
e961811f	187	static inline unsigned int dccp_csum_coverage(const struct sk_buff *skb)
6f4e5fff GR	188	{
	189	const struct dccp_hdr* dh = dccp_hdr(skb);
	190
	191	if (dh->dccph_cscov == 0)
	192	return skb->len;
	193	return (dh->dccph_doff + dh->dccph_cscov - 1) * sizeof(u32);
	194	}
	195
	196	static inline void dccp_csum_outgoing(struct sk_buff *skb)
	197	{
e961811f	198	unsigned int cov = dccp_csum_coverage(skb);
6f4e5fff GR	199
	200	if (cov >= skb->len)
	201	dccp_hdr(skb)->dccph_cscov = 0;
	202
	203	skb->csum = skb_checksum(skb, 0, (cov > skb->len)? skb->len : cov, 0);
	204	}
	205
	206	extern void dccp_v4_send_check(struct sock sk, int len, struct sk_buff skb);
	207
7c657876 ACM	208	extern int dccp_retransmit_skb(struct sock sk, struct sk_buff skb);
7c657876 ACM	209
7c657876 ACM	210	extern void dccp_send_ack(struct sock *sk);
7c657876 ACM	211	extern void dccp_send_delayed_ack(struct sock *sk);
8a73cd09 GR	212	extern void dccp_reqsk_send_ack(struct sk_buff sk, struct request_sock rsk);
8a73cd09 GR	213
e92ae93a ACM	214	extern void dccp_send_sync(struct sock *sk, const u64 seq,
e92ae93a ACM	215	const enum dccp_pkt_type pkt_type);
7c657876	216
97e5848d	217	extern void dccp_write_xmit(struct sock *sk, int block);
c530cfb1	218	extern void dccp_write_space(struct sock *sk);
27258ee5	219
7c657876 ACM	220	extern void dccp_init_xmit_timers(struct sock *sk);
	221	static inline void dccp_clear_xmit_timers(struct sock *sk)
	222	{
	223	inet_csk_clear_xmit_timers(sk);
	224	}
	225
	226	extern unsigned int dccp_sync_mss(struct sock *sk, u32 pmtu);
	227
	228	extern const char *dccp_packet_name(const int type);
	229	extern const char *dccp_state_name(const int state);
	230
c25a18ba ACM	231	extern void dccp_set_state(struct sock *sk, const int state);
c25a18ba ACM	232	extern void dccp_done(struct sock *sk);
7c657876	233
cf557926	234	extern void dccp_reqsk_init(struct request_sock req, struct sk_buff skb);
7c657876	235
7c657876 ACM	236	extern int dccp_v4_conn_request(struct sock sk, struct sk_buff skb);
	237
	238	extern struct sock dccp_create_openreq_child(struct sock sk,
	239	const struct request_sock *req,
	240	const struct sk_buff *skb);
	241
	242	extern int dccp_v4_do_rcv(struct sock sk, struct sk_buff skb);
	243
7c657876 ACM	244	extern struct sock dccp_v4_request_recv_sock(struct sock sk,
	245	struct sk_buff *skb,
	246	struct request_sock *req,
	247	struct dst_entry *dst);
	248	extern struct sock dccp_check_req(struct sock sk, struct sk_buff *skb,
	249	struct request_sock *req,
	250	struct request_sock **prev);
	251
	252	extern int dccp_child_process(struct sock parent, struct sock child,
	253	struct sk_buff *skb);
	254	extern int dccp_rcv_state_process(struct sock sk, struct sk_buff skb,
	255	struct dccp_hdr *dh, unsigned len);
	256	extern int dccp_rcv_established(struct sock sk, struct sk_buff skb,
	257	const struct dccp_hdr *dh, const unsigned len);
	258
72478873	259	extern int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized);
3e0fadc5	260	extern int dccp_destroy_sock(struct sock *sk);
f21e68ca	261
7c657876 ACM	262	extern void dccp_close(struct sock *sk, long timeout);
	263	extern struct sk_buff dccp_make_response(struct sock sk,
	264	struct dst_entry *dst,
	265	struct request_sock *req);
	266
	267	extern int dccp_connect(struct sock *sk);
	268	extern int dccp_disconnect(struct sock *sk, int flags);
c985ed70	269	extern void dccp_hash(struct sock *sk);
f21e68ca	270	extern void dccp_unhash(struct sock *sk);
7c657876	271	extern int dccp_getsockopt(struct sock *sk, int level, int optname,
a1d3a355 ACM	272	char __user optval, int __user optlen);
	273	extern int dccp_setsockopt(struct sock *sk, int level, int optname,
	274	char __user *optval, int optlen);
3fdadf7d DM	275	#ifdef CONFIG_COMPAT
	276	extern int compat_dccp_getsockopt(struct sock *sk,
	277	int level, int optname,
	278	char __user optval, int __user optlen);
	279	extern int compat_dccp_setsockopt(struct sock *sk,
	280	int level, int optname,
	281	char __user *optval, int optlen);
	282	#endif
7c657876	283	extern int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg);
7690af3f ACM	284	extern int dccp_sendmsg(struct kiocb iocb, struct sock sk,
7690af3f ACM	285	struct msghdr *msg, size_t size);
7c657876 ACM	286	extern int dccp_recvmsg(struct kiocb iocb, struct sock sk,
	287	struct msghdr *msg, size_t len, int nonblock,
	288	int flags, int *addr_len);
7c657876	289	extern void dccp_shutdown(struct sock *sk, int how);
f21e68ca ACM	290	extern int inet_dccp_listen(struct socket *sock, int backlog);
	291	extern unsigned int dccp_poll(struct file file, struct socket sock,
	292	poll_table *wait);
f21e68ca ACM	293	extern int dccp_v4_connect(struct sock sk, struct sockaddr uaddr,
f21e68ca ACM	294	int addr_len);
7c657876	295
017487d7	296	extern int dccp_send_reset(struct sock *sk, enum dccp_reset_codes code);
7ad07e7c	297	extern void dccp_send_close(struct sock *sk, const int active);
f21e68ca	298	extern int dccp_invalid_packet(struct sk_buff *skb);
4712a792 GR	299	extern u32 dccp_sample_rtt(struct sock sk, struct timeval t_recv,
4712a792 GR	300	struct timeval *t_history);
f21e68ca ACM	301
f21e68ca ACM	302	static inline int dccp_bad_service_code(const struct sock *sk,
60fe62e7	303	const __be32 service)
f21e68ca ACM	304	{
	305	const struct dccp_sock *dp = dccp_sk(sk);
	306
	307	if (dp->dccps_service == service)
	308	return 0;
	309	return !dccp_list_has_service(dp->dccps_service_list, service);
	310	}
7c657876 ACM	311
7c657876 ACM	312	struct dccp_skb_cb {
67e6b629 ACM	313	__u8 dccpd_type:4;
	314	__u8 dccpd_ccval:4;
	315	__u8 dccpd_reset_code;
	316	__u16 dccpd_opt_len;
7c657876 ACM	317	__u64 dccpd_seq;
7c657876 ACM	318	__u64 dccpd_ack_seq;
7c657876 ACM	319	};
	320
	321	#define DCCP_SKB_CB(__skb) ((struct dccp_skb_cb *)&((__skb)->cb[0]))
	322
	323	static inline int dccp_non_data_packet(const struct sk_buff *skb)
	324	{
	325	const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
	326
	327	return type == DCCP_PKT_ACK \|\|
	328	type == DCCP_PKT_CLOSE \|\|
	329	type == DCCP_PKT_CLOSEREQ \|\|
	330	type == DCCP_PKT_RESET \|\|
	331	type == DCCP_PKT_SYNC \|\|
	332	type == DCCP_PKT_SYNCACK;
	333	}
	334
	335	static inline int dccp_packet_without_ack(const struct sk_buff *skb)
	336	{
	337	const __u8 type = DCCP_SKB_CB(skb)->dccpd_type;
	338
	339	return type == DCCP_PKT_DATA \|\| type == DCCP_PKT_REQUEST;
	340	}
	341
6b811d43	342	#define DCCP_PKT_WITHOUT_ACK_SEQ (UINT48_MAX << 2)
7c657876 ACM	343
	344	static inline void dccp_hdr_set_seq(struct dccp_hdr *dh, const u64 gss)
	345	{
7690af3f ACM	346	struct dccp_hdr_ext dhx = (struct dccp_hdr_ext )((void *)dh +
7690af3f ACM	347	sizeof(*dh));
60fe62e7 AB	348	dh->dccph_seq2 = 0;
60fe62e7 AB	349	dh->dccph_seq = htons((gss >> 32) & 0xfffff);
7c657876 ACM	350	dhx->dccph_seq_low = htonl(gss & 0xffffffff);
	351	}
	352
7690af3f ACM	353	static inline void dccp_hdr_set_ack(struct dccp_hdr_ack_bits *dhack,
7690af3f ACM	354	const u64 gsr)
7c657876	355	{
60fe62e7 AB	356	dhack->dccph_reserved1 = 0;
60fe62e7 AB	357	dhack->dccph_ack_nr_high = htons(gsr >> 32);
7c657876 ACM	358	dhack->dccph_ack_nr_low = htonl(gsr & 0xffffffff);
	359	}
	360
	361	static inline void dccp_update_gsr(struct sock *sk, u64 seq)
	362	{
	363	struct dccp_sock *dp = dccp_sk(sk);
a4bf3902	364	const struct dccp_minisock *dmsk = dccp_msk(sk);
7c657876	365
03ace394 ACM	366	dp->dccps_gsr = seq;
03ace394 ACM	367	dccp_set_seqno(&dp->dccps_swl,
a4bf3902	368	dp->dccps_gsr + 1 - (dmsk->dccpms_sequence_window / 4));
7c657876	369	dccp_set_seqno(&dp->dccps_swh,
a4bf3902	370	dp->dccps_gsr + (3 * dmsk->dccpms_sequence_window) / 4);
7c657876 ACM	371	}
	372
	373	static inline void dccp_update_gss(struct sock *sk, u64 seq)
	374	{
	375	struct dccp_sock *dp = dccp_sk(sk);
7c657876	376
03ace394 ACM	377	dp->dccps_awh = dp->dccps_gss = seq;
03ace394 ACM	378	dccp_set_seqno(&dp->dccps_awl,
7690af3f	379	(dp->dccps_gss -
a4bf3902	380	dccp_msk(sk)->dccpms_sequence_window + 1));
7c657876	381	}
c9eaf173	382
ae31c339 ACM	383	static inline int dccp_ack_pending(const struct sock *sk)
	384	{
	385	const struct dccp_sock *dp = dccp_sk(sk);
	386	return dp->dccps_timestamp_echo != 0 \|\|
	387	#ifdef CONFIG_IP_DCCP_ACKVEC
a4bf3902	388	(dccp_msk(sk)->dccpms_send_ack_vector &&
ae31c339 ACM	389	dccp_ackvec_pending(dp->dccps_hc_rx_ackvec)) \|\|
	390	#endif
	391	inet_csk_ack_scheduled(sk);
	392	}
7c657876	393
2d0817d1 ACM	394	extern int dccp_insert_options(struct sock sk, struct sk_buff skb);
2d0817d1 ACM	395	extern int dccp_insert_option_elapsed_time(struct sock *sk,
7c657876 ACM	396	struct sk_buff *skb,
7c657876 ACM	397	u32 elapsed_time);
2d0817d1	398	extern int dccp_insert_option_timestamp(struct sock *sk,
d4b81ff7	399	struct sk_buff *skb);
2d0817d1	400	extern int dccp_insert_option(struct sock sk, struct sk_buff skb,
7c657876 ACM	401	unsigned char option,
	402	const void *value, unsigned char len);
	403
b0e56780 ACM	404	extern void dccp_timestamp(const struct sock sk, struct timeval tv);
b0e56780 ACM	405
b6ee3d4a ACM	406	static inline suseconds_t timeval_usecs(const struct timeval *tv)
	407	{
	408	return tv->tv_sec * USEC_PER_SEC + tv->tv_usec;
	409	}
	410
	411	static inline suseconds_t timeval_delta(const struct timeval *large,
	412	const struct timeval *small)
	413	{
	414	time_t secs = large->tv_sec - small->tv_sec;
	415	suseconds_t usecs = large->tv_usec - small->tv_usec;
	416
	417	if (usecs < 0) {
	418	secs--;
	419	usecs += USEC_PER_SEC;
	420	}
	421	return secs * USEC_PER_SEC + usecs;
	422	}
	423
	424	static inline void timeval_add_usecs(struct timeval *tv,
	425	const suseconds_t usecs)
	426	{
	427	tv->tv_usec += usecs;
	428	while (tv->tv_usec >= USEC_PER_SEC) {
	429	tv->tv_sec++;
	430	tv->tv_usec -= USEC_PER_SEC;
	431	}
	432	}
	433
	434	static inline void timeval_sub_usecs(struct timeval *tv,
	435	const suseconds_t usecs)
	436	{
	437	tv->tv_usec -= usecs;
	438	while (tv->tv_usec < 0) {
	439	tv->tv_sec--;
	440	tv->tv_usec += USEC_PER_SEC;
	441	}
0f9e5b57	442	DCCP_BUG_ON(tv->tv_sec < 0);
b6ee3d4a ACM	443	}
b6ee3d4a ACM	444
e55d912f ACM	445	#ifdef CONFIG_SYSCTL
	446	extern int dccp_sysctl_init(void);
	447	extern void dccp_sysctl_exit(void);
	448	#else
	449	static inline int dccp_sysctl_init(void)
	450	{
	451	return 0;
	452	}
	453
	454	static inline void dccp_sysctl_exit(void)
	455	{
	456	}
	457	#endif
	458
7c657876	459	#endif /* _DCCP_H */