#include <sys/cdefs.h>
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_tcpdebug.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/eventhandler.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/systm.h>
#include <vm/uma.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/ip_options.h>
#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h>
#include <netinet6/nd6.h>
#include <netinet/tcp.h>
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h>
#include <netinet/tcp_var.h>
#include <netinet6/tcp6_var.h>
#include <netinet/tcpip.h>

Include dependency graph for tcp_reass.c:

Macros
#define	TCP_R_LOG_ADD 1

#define	TCP_R_LOG_LIMIT_REACHED 2

#define	TCP_R_LOG_APPEND 3

#define	TCP_R_LOG_PREPEND 4

#define	TCP_R_LOG_REPLACE 5

#define	TCP_R_LOG_MERGE_INTO 6

#define	TCP_R_LOG_NEW_ENTRY 7

#define	TCP_R_LOG_READ 8

#define	TCP_R_LOG_ZERO 9

#define	TCP_R_LOG_DUMP 10

#define	TCP_R_LOG_TRIM 11

Functions
	__FBSDID ("$FreeBSD$")

static	SYSCTL_NODE (_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW\|CTLFLAG_MPSAFE, 0, "TCP Segment Reassembly Queue")

static	SYSCTL_NODE (_net_inet_tcp_reass, OID_AUTO, stats, CTLFLAG_RW\|CTLFLAG_MPSAFE, 0, "TCP Segment Reassembly stats")

	SYSCTL_INT (_net_inet_tcp_reass, OID_AUTO, maxsegments, CTLFLAG_RDTUN, &tcp_reass_maxseg, 0, "Global maximum number of TCP Segments in Reassembly Queue")

	SYSCTL_UMA_CUR (_net_inet_tcp_reass, OID_AUTO, cursegments, 0, &tcp_reass_zone, "Global number of TCP Segments currently in Reassembly Queue")

	SYSCTL_UINT (_net_inet_tcp_reass, OID_AUTO, maxqueuelen, CTLFLAG_RWTUN, &tcp_reass_maxqueuelen, 0, "Maximum number of TCP Segments per Reassembly Queue")

	SYSCTL_INT (_net_inet_tcp_reass, OID_AUTO, new_limit, CTLFLAG_RWTUN, &tcp_new_limits, 0, "Do we use the new limit method we are discussing?")

	SYSCTL_UINT (_net_inet_tcp_reass, OID_AUTO, queueguard, CTLFLAG_RWTUN, &tcp_reass_queue_guard, 16, "Number of TCP Segments in Reassembly Queue where we flip over to guard mode")

static void	tcp_reass_zone_change (void *tag)

void	tcp_reass_global_init (void)

void	tcp_reass_flush (struct tcpcb *tp)

static void	tcp_reass_append (struct tcpcb tp, struct tseg_qent last, struct mbuf m, struct tcphdr th, int tlen, struct mbuf *mlast, int lenofoh)

static void	tcp_reass_prepend (struct tcpcb tp, struct tseg_qent first, struct mbuf m, struct tcphdr th, int tlen, struct mbuf *mlast, int lenofoh)

static void	tcp_reass_replace (struct tcpcb tp, struct tseg_qent q, struct mbuf m, tcp_seq seq, int len, struct mbuf mlast, int mbufoh, uint16_t flags)

static void	tcp_reass_merge_into (struct tcpcb tp, struct tseg_qent ent, struct tseg_qent *q)

static void	tcp_reass_merge_forward (struct tcpcb tp, struct tseg_qent ent)

static int	tcp_reass_overhead_of_chain (struct mbuf m, struct mbuf *mlast)

int	tcp_reass (struct tcpcb tp, struct tcphdr th, tcp_seq seq_start, int tlenp, struct mbuf *m)

Variables
static int	tcp_reass_maxseg = 0

static uma_zone_t	tcp_reass_zone

static u_int	tcp_reass_maxqueuelen = 100

static int	tcp_new_limits = 0

static u_int	tcp_reass_queue_guard = 16

Macro Definition Documentation

◆ TCP_R_LOG_ADD

#define TCP_R_LOG_ADD 1

Definition at line 89 of file tcp_reass.c.

◆ TCP_R_LOG_APPEND

#define TCP_R_LOG_APPEND 3

Definition at line 91 of file tcp_reass.c.

◆ TCP_R_LOG_DUMP

#define TCP_R_LOG_DUMP 10

Definition at line 98 of file tcp_reass.c.

◆ TCP_R_LOG_LIMIT_REACHED

#define TCP_R_LOG_LIMIT_REACHED 2

Definition at line 90 of file tcp_reass.c.

◆ TCP_R_LOG_MERGE_INTO

#define TCP_R_LOG_MERGE_INTO 6

Definition at line 94 of file tcp_reass.c.

◆ TCP_R_LOG_NEW_ENTRY

#define TCP_R_LOG_NEW_ENTRY 7

Definition at line 95 of file tcp_reass.c.

◆ TCP_R_LOG_PREPEND

#define TCP_R_LOG_PREPEND 4

Definition at line 92 of file tcp_reass.c.

◆ TCP_R_LOG_READ

#define TCP_R_LOG_READ 8

Definition at line 96 of file tcp_reass.c.

◆ TCP_R_LOG_REPLACE

#define TCP_R_LOG_REPLACE 5

Definition at line 93 of file tcp_reass.c.

◆ TCP_R_LOG_TRIM

#define TCP_R_LOG_TRIM 11

Definition at line 99 of file tcp_reass.c.

◆ TCP_R_LOG_ZERO

#define TCP_R_LOG_ZERO 9

Definition at line 97 of file tcp_reass.c.

Function Documentation

◆ __FBSDID()

__FBSDID ( "$FreeBSD$" )

◆ SYSCTL_INT() [1/2]

SYSCTL_INT	(	_net_inet_tcp_reass	,
		OID_AUTO	,
		maxsegments	,
		CTLFLAG_RDTUN	,
		&	tcp_reass_maxseg,
		0	,
		"Global maximum number of TCP Segments in Reassembly Queue"
	)

◆ SYSCTL_INT() [2/2]

SYSCTL_INT	(	_net_inet_tcp_reass	,
		OID_AUTO	,
		new_limit	,
		CTLFLAG_RWTUN	,
		&	tcp_new_limits,
		0	,
		"Do we use the new limit method we are discussing?"
	)

◆ SYSCTL_NODE() [1/2]

static SYSCTL_NODE	(	_net_inet_tcp	,
		OID_AUTO	,
		reass	,
		CTLFLAG_RW\|	CTLFLAG_MPSAFE,
		0	,
		"TCP Segment Reassembly Queue"
	)

static

◆ SYSCTL_NODE() [2/2]

static SYSCTL_NODE	(	_net_inet_tcp_reass	,
		OID_AUTO	,
		stats	,
		CTLFLAG_RW\|	CTLFLAG_MPSAFE,
		0	,
		"TCP Segment Reassembly stats"
	)

static

◆ SYSCTL_UINT() [1/2]

SYSCTL_UINT	(	_net_inet_tcp_reass	,
		OID_AUTO	,
		maxqueuelen	,
		CTLFLAG_RWTUN	,
		&	tcp_reass_maxqueuelen,
		0	,
		"Maximum number of TCP Segments per Reassembly Queue"
	)

◆ SYSCTL_UINT() [2/2]

SYSCTL_UINT	(	_net_inet_tcp_reass	,
		OID_AUTO	,
		queueguard	,
		CTLFLAG_RWTUN	,
		&	tcp_reass_queue_guard,
		16	,
		"Number of TCP Segments in Reassembly Queue where we flip over to guard mode"
	)

◆ SYSCTL_UMA_CUR()

SYSCTL_UMA_CUR	(	_net_inet_tcp_reass	,
		OID_AUTO	,
		cursegments	,
		0	,
		&	tcp_reass_zone,
		"Global number of TCP Segments currently in Reassembly Queue"
	)

◆ tcp_reass()

int tcp_reass	(	struct tcpcb *	tp,
		struct tcphdr *	th,
		tcp_seq *	seq_start,
		int *	tlenp,
		struct mbuf *	m
	)

                           +--last
                           v

reassembly buffer |—| |—| |—| new segment |—|

                           +--last
                           v

reassembly buffer |—| |—| |—| new segment |—|

  first-------+
              v

rea: |—| |—| |—| new: |—| Note the case we do not deal with here is: rea= |—| |—| |—| new= |-—| Due to the fact that it could be new |-----------------—| And we might need to merge forward.

     first---->+
                v

rea= |—| .... new" |—|

Now is this fit just in-between only? i.e.: p—+ +-—q v v res= |–| |–| |–| nee |-|

If we reach here we have some (possibly all) overlap such as: res= |–| |–| |–| new= |-—| or new= |--------------—| or new= |-----—| or new= |—| or new= |--------—|

 prev seg---->+
              v

reassembly buffer |—| new segment |-|

 prev seg---->+
              v

reassembly buffer |—| new segment |--—|

  prev seg---->+
               v

reassembly buffer |–| |—| new segment |–| (note: it was trimmed above if it overlapped)

       next seg---->+
                    v

reassembly buffer |–| |—| new segment |-------—|

          next seg---->+
                       v

reassembly buffer |–| |—| new segment |-------—|

Definition at line 526 of file tcp_reass.c.

References inpcb::inp_inc, inpcb::inp_socket, INP_WLOCK_ASSERT, tcpcb::rcv_nxt, SEQ_GEQ, SEQ_GT, SEQ_LEQ, SEQ_LT, tcpcb::t_flags, tcpcb::t_inpcb, tcpcb::t_maxseg, tcpcb::t_rcvoopack, tcpcb::t_segq, tcpcb::t_segqlen, tcpcb::t_segqmbuflen, tcpcb::t_state, tcp_get_flags(), tcp_log_addrs(), tcp_new_limits, TCP_R_LOG_ADD, TCP_R_LOG_LIMIT_REACHED, TCP_R_LOG_NEW_ENTRY, TCP_R_LOG_READ, TCP_R_LOG_TRIM, TCP_R_LOG_ZERO, tcp_reass_append(), tcp_reass_maxqueuelen, tcp_reass_merge_forward(), tcp_reass_overhead_of_chain(), tcp_reass_prepend(), tcp_reass_queue_guard, tcp_reass_replace(), tcp_reass_zone, TCPS_HAVEESTABLISHED, tcps_rcvmemdrop, TCPSTAT_ADD, TCPSTAT_INC, TF_WAKESOR, tseg_qent::tqe_flags, tseg_qent::tqe_last, tseg_qent::tqe_len, tseg_qent::tqe_m, tseg_qent::tqe_mbuf_cnt, and tseg_qent::tqe_start.

Referenced by bbr_do_syn_recv(), bbr_process_data(), rack_do_syn_recv(), rack_process_data(), and tcp_do_segment().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ tcp_reass_append()

static void tcp_reass_append	(	struct tcpcb *	tp,
		struct tseg_qent *	last,
		struct mbuf *	m,
		struct tcphdr *	th,
		int	tlen,
		struct mbuf *	mlast,
		int	lenofoh
	)

static

Definition at line 324 of file tcp_reass.c.

References tcpcb::t_rcvoopack, tcp_get_flags(), TCP_R_LOG_APPEND, TCPSTAT_ADD, TCPSTAT_INC, tseg_qent::tqe_flags, tseg_qent::tqe_last, tseg_qent::tqe_len, tseg_qent::tqe_m, tseg_qent::tqe_mbuf_cnt, and tseg_qent::tqe_start.

Referenced by tcp_reass().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ tcp_reass_flush()

void tcp_reass_flush ( struct tcpcb * tp )

Definition at line 305 of file tcp_reass.c.

References INP_WLOCK_ASSERT, tcpcb::t_inpcb, tcpcb::t_segq, tcpcb::t_segqlen, tcpcb::t_segqmbuflen, tcp_reass_zone, and tseg_qent::tqe_m.

Referenced by tcp_discardcb(), and tcp_drain().

Here is the caller graph for this function:

◆ tcp_reass_global_init()

void tcp_reass_global_init ( void )

Definition at line 273 of file tcp_reass.c.

References tcp_reass_maxseg, tcp_reass_zone, and tcp_reass_zone_change().

Referenced by tcp_init().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ tcp_reass_merge_forward()

static void tcp_reass_merge_forward	(	struct tcpcb *	tp,
		struct tseg_qent *	ent
	)

static

Definition at line 446 of file tcp_reass.c.

References SEQ_GEQ, SEQ_GT, tcpcb::t_segq, tcpcb::t_segqlen, tcpcb::t_segqmbuflen, TCP_R_LOG_TRIM, tcp_reass_merge_into(), tcp_reass_zone, tseg_qent::tqe_len, tseg_qent::tqe_m, tseg_qent::tqe_mbuf_cnt, and tseg_qent::tqe_start.

Referenced by tcp_reass().

Here is the call graph for this function:

Here is the caller graph for this function:

◆ tcp_reass_merge_into()

static void tcp_reass_merge_into	(	struct tcpcb *	tp,
		struct tseg_qent *	ent,
		struct tseg_qent *	q
	)

static

Definition at line 421 of file tcp_reass.c.

References tcpcb::t_segq, tcpcb::t_segqlen, TCP_R_LOG_MERGE_INTO, tcp_reass_zone, tseg_qent::tqe_flags, tseg_qent::tqe_last, tseg_qent::tqe_len, tseg_qent::tqe_m, and tseg_qent::tqe_mbuf_cnt.

Referenced by tcp_reass_merge_forward().

Here is the caller graph for this function:

◆ tcp_reass_overhead_of_chain()

static int tcp_reass_overhead_of_chain	(	struct mbuf *	m,
		struct mbuf **	mlast
	)

static

Definition at line 498 of file tcp_reass.c.

Referenced by tcp_reass().

Here is the caller graph for this function:

◆ tcp_reass_prepend()

static void tcp_reass_prepend	(	struct tcpcb *	tp,
		struct tseg_qent *	first,
		struct mbuf *	m,
		struct tcphdr *	th,
		int	tlen,
		struct mbuf *	mlast,
		int	lenofoh
	)

static

Definition at line 350 of file tcp_reass.c.

References SEQ_GT, tcpcb::t_rcvoopack, TCP_R_LOG_PREPEND, TCP_R_LOG_TRIM, TCPSTAT_ADD, TCPSTAT_INC, tseg_qent::tqe_len, tseg_qent::tqe_m, tseg_qent::tqe_mbuf_cnt, and tseg_qent::tqe_start.

Referenced by tcp_reass().

Here is the caller graph for this function:

◆ tcp_reass_replace()

static void tcp_reass_replace	(	struct tcpcb *	tp,
		struct tseg_qent *	q,
		struct mbuf *	m,
		tcp_seq	seq,
		int	len,
		struct mbuf *	mlast,
		int	mbufoh,
		uint16_t	flags
	)

static

Definition at line 386 of file tcp_reass.c.

References tcpcb::t_rcvoopack, tcpcb::t_segqmbuflen, TCP_R_LOG_REPLACE, TCPSTAT_ADD, TCPSTAT_INC, tseg_qent::tqe_flags, tseg_qent::tqe_last, tseg_qent::tqe_len, tseg_qent::tqe_m, tseg_qent::tqe_mbuf_cnt, and tseg_qent::tqe_start.

Referenced by tcp_reass().

Here is the caller graph for this function:

◆ tcp_reass_zone_change()

static void tcp_reass_zone_change ( void * tag )

static

Definition at line 192 of file tcp_reass.c.

References tcp_reass_maxseg, and tcp_reass_zone.

Referenced by tcp_reass_global_init().

Here is the caller graph for this function:

Variable Documentation

◆ tcp_new_limits

int tcp_new_limits = 0

static

Definition at line 124 of file tcp_reass.c.

Referenced by tcp_reass().

◆ tcp_reass_maxqueuelen

u_int tcp_reass_maxqueuelen = 100

static

Definition at line 119 of file tcp_reass.c.

Referenced by tcp_reass().

◆ tcp_reass_maxseg

int tcp_reass_maxseg = 0

static

Definition at line 109 of file tcp_reass.c.

Referenced by tcp_reass_global_init(), and tcp_reass_zone_change().

◆ tcp_reass_queue_guard

u_int tcp_reass_queue_guard = 16

static

Definition at line 129 of file tcp_reass.c.

Referenced by tcp_reass().

◆ tcp_reass_zone

uma_zone_t tcp_reass_zone

static

Definition at line 114 of file tcp_reass.c.

Referenced by tcp_reass(), tcp_reass_flush(), tcp_reass_global_init(), tcp_reass_merge_forward(), tcp_reass_merge_into(), and tcp_reass_zone_change().

Macros

Functions

Variables

Macro Definition Documentation

◆ TCP_R_LOG_ADD

◆ TCP_R_LOG_APPEND

◆ TCP_R_LOG_DUMP

◆ TCP_R_LOG_LIMIT_REACHED

◆ TCP_R_LOG_MERGE_INTO

◆ TCP_R_LOG_NEW_ENTRY

◆ TCP_R_LOG_PREPEND

◆ TCP_R_LOG_READ

◆ TCP_R_LOG_REPLACE

◆ TCP_R_LOG_TRIM

◆ TCP_R_LOG_ZERO

Function Documentation

◆ __FBSDID()

◆ SYSCTL_INT() [1/2]

◆ SYSCTL_INT() [2/2]

◆ SYSCTL_NODE() [1/2]

◆ SYSCTL_NODE() [2/2]

◆ SYSCTL_UINT() [1/2]

◆ SYSCTL_UINT() [2/2]

◆ SYSCTL_UMA_CUR()

◆ tcp_reass()

◆ tcp_reass_append()

◆ tcp_reass_flush()

◆ tcp_reass_global_init()

◆ tcp_reass_merge_forward()

◆ tcp_reass_merge_into()

◆ tcp_reass_overhead_of_chain()

◆ tcp_reass_prepend()

◆ tcp_reass_replace()

◆ tcp_reass_zone_change()

Variable Documentation

◆ tcp_new_limits

◆ tcp_reass_maxqueuelen

◆ tcp_reass_maxseg

◆ tcp_reass_queue_guard

◆ tcp_reass_zone