freebsd-skq/sys/netinet/tcp_usrreq.c
John Baldwin 82334850ea Add an external mbuf buffer type that holds multiple unmapped pages.
Unmapped mbufs allow sendfile to carry multiple pages of data in a
single mbuf, without mapping those pages.  It is a requirement for
Netflix's in-kernel TLS, and provides a 5-10% CPU savings on heavy web
serving workloads when used by sendfile, due to effectively
compressing socket buffers by an order of magnitude, and hence
reducing cache misses.

For this new external mbuf buffer type (EXT_PGS), the ext_buf pointer
now points to a struct mbuf_ext_pgs structure instead of a data
buffer.  This structure contains an array of physical addresses (this
reduces cache misses compared to an earlier version that stored an
array of vm_page_t pointers).  It also stores additional fields needed
for in-kernel TLS such as the TLS header and trailer data that are
currently unused.  To more easily detect these mbufs, the M_NOMAP flag
is set in m_flags in addition to M_EXT.

Various functions like m_copydata() have been updated to safely access
packet contents (using uiomove_fromphys()), to make things like BPF
safe.

NIC drivers advertise support for unmapped mbufs on transmit via a new
IFCAP_NOMAP capability.  This capability can be toggled via the new
'nomap' and '-nomap' ifconfig(8) commands.  For NIC drivers that only
transmit packet contents via DMA and use bus_dma, adding the
capability to if_capabilities and if_capenable should be all that is
required.

If a NIC does not support unmapped mbufs, they are converted to a
chain of mapped mbufs (using sf_bufs to provide the mapping) in
ip_output or ip6_output.  If an unmapped mbuf requires software
checksums, it is also converted to a chain of mapped mbufs before
computing the checksum.

Submitted by:	gallatin (earlier version)
Reviewed by:	gallatin, hselasky, rrs
Discussed with:	ae, kp (firewalls)
Relnotes:	yes
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D20616
2019-06-29 00:48:33 +00:00

2678 lines
65 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1982, 1986, 1988, 1993
* The Regents of the University of California.
* Copyright (c) 2006-2007 Robert N. M. Watson
* Copyright (c) 2010-2011 Juniper Networks, Inc.
* All rights reserved.
*
* Portions of this software were developed by Robert N. M. Watson under
* contract to Juniper Networks, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* From: @(#)tcp_usrreq.c 8.2 (Berkeley) 1/3/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ddb.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include "opt_tcpdebug.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/limits.h>
#include <sys/malloc.h>
#include <sys/refcount.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#ifdef INET6
#include <sys/domain.h>
#endif /* INET6 */
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/protosw.h>
#include <sys/proc.h>
#include <sys/jail.h>
#include <sys/syslog.h>
#ifdef DDB
#include <ddb/ddb.h>
#endif
#include <net/if.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_kdtrace.h>
#include <netinet/in_pcb.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h>
#include <netinet6/scope6_var.h>
#endif
#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 <netinet/tcp_log_buf.h>
#include <netinet/tcpip.h>
#include <netinet/cc/cc.h>
#include <netinet/tcp_fastopen.h>
#include <netinet/tcp_hpts.h>
#ifdef TCPPCAP
#include <netinet/tcp_pcap.h>
#endif
#ifdef TCPDEBUG
#include <netinet/tcp_debug.h>
#endif
#ifdef TCP_OFFLOAD
#include <netinet/tcp_offload.h>
#endif
#include <netipsec/ipsec_support.h>
/*
* TCP protocol interface to socket abstraction.
*/
static int tcp_attach(struct socket *);
#ifdef INET
static int tcp_connect(struct tcpcb *, struct sockaddr *,
struct thread *td);
#endif /* INET */
#ifdef INET6
static int tcp6_connect(struct tcpcb *, struct sockaddr *,
struct thread *td);
#endif /* INET6 */
static void tcp_disconnect(struct tcpcb *);
static void tcp_usrclosed(struct tcpcb *);
static void tcp_fill_info(struct tcpcb *, struct tcp_info *);
#ifdef TCPDEBUG
#define TCPDEBUG0 int ostate = 0
#define TCPDEBUG1() ostate = tp ? tp->t_state : 0
#define TCPDEBUG2(req) if (tp && (so->so_options & SO_DEBUG)) \
tcp_trace(TA_USER, ostate, tp, 0, 0, req)
#else
#define TCPDEBUG0
#define TCPDEBUG1()
#define TCPDEBUG2(req)
#endif
/*
* TCP attaches to socket via pru_attach(), reserving space,
* and an internet control block.
*/
static int
tcp_usr_attach(struct socket *so, int proto, struct thread *td)
{
struct inpcb *inp;
struct tcpcb *tp = NULL;
int error;
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp == NULL, ("tcp_usr_attach: inp != NULL"));
TCPDEBUG1();
error = tcp_attach(so);
if (error)
goto out;
if ((so->so_options & SO_LINGER) && so->so_linger == 0)
so->so_linger = TCP_LINGERTIME;
inp = sotoinpcb(so);
tp = intotcpcb(inp);
out:
TCPDEBUG2(PRU_ATTACH);
TCP_PROBE2(debug__user, tp, PRU_ATTACH);
return error;
}
/*
* tcp_detach is called when the socket layer loses its final reference
* to the socket, be it a file descriptor reference, a reference from TCP,
* etc. At this point, there is only one case in which we will keep around
* inpcb state: time wait.
*
* This function can probably be re-absorbed back into tcp_usr_detach() now
* that there is a single detach path.
*/
static void
tcp_detach(struct socket *so, struct inpcb *inp)
{
struct tcpcb *tp;
INP_INFO_LOCK_ASSERT(&V_tcbinfo);
INP_WLOCK_ASSERT(inp);
KASSERT(so->so_pcb == inp, ("tcp_detach: so_pcb != inp"));
KASSERT(inp->inp_socket == so, ("tcp_detach: inp_socket != so"));
tp = intotcpcb(inp);
if (inp->inp_flags & INP_TIMEWAIT) {
/*
* There are two cases to handle: one in which the time wait
* state is being discarded (INP_DROPPED), and one in which
* this connection will remain in timewait. In the former,
* it is time to discard all state (except tcptw, which has
* already been discarded by the timewait close code, which
* should be further up the call stack somewhere). In the
* latter case, we detach from the socket, but leave the pcb
* present until timewait ends.
*
* XXXRW: Would it be cleaner to free the tcptw here?
*
* Astute question indeed, from twtcp perspective there are
* four cases to consider:
*
* #1 tcp_detach is called at tcptw creation time by
* tcp_twstart, then do not discard the newly created tcptw
* and leave inpcb present until timewait ends
* #2 tcp_detach is called at tcptw creation time by
* tcp_twstart, but connection is local and tw will be
* discarded immediately
* #3 tcp_detach is called at timewait end (or reuse) by
* tcp_twclose, then the tcptw has already been discarded
* (or reused) and inpcb is freed here
* #4 tcp_detach is called() after timewait ends (or reuse)
* (e.g. by soclose), then tcptw has already been discarded
* (or reused) and inpcb is freed here
*
* In all three cases the tcptw should not be freed here.
*/
if (inp->inp_flags & INP_DROPPED) {
in_pcbdetach(inp);
if (__predict_true(tp == NULL)) {
in_pcbfree(inp);
} else {
/*
* This case should not happen as in TIMEWAIT
* state the inp should not be destroyed before
* its tcptw. If INVARIANTS is defined, panic.
*/
#ifdef INVARIANTS
panic("%s: Panic before an inp double-free: "
"INP_TIMEWAIT && INP_DROPPED && tp != NULL"
, __func__);
#else
log(LOG_ERR, "%s: Avoid an inp double-free: "
"INP_TIMEWAIT && INP_DROPPED && tp != NULL"
, __func__);
#endif
INP_WUNLOCK(inp);
}
} else {
in_pcbdetach(inp);
INP_WUNLOCK(inp);
}
} else {
/*
* If the connection is not in timewait, we consider two
* two conditions: one in which no further processing is
* necessary (dropped || embryonic), and one in which TCP is
* not yet done, but no longer requires the socket, so the
* pcb will persist for the time being.
*
* XXXRW: Does the second case still occur?
*/
if (inp->inp_flags & INP_DROPPED ||
tp->t_state < TCPS_SYN_SENT) {
tcp_discardcb(tp);
in_pcbdetach(inp);
in_pcbfree(inp);
} else {
in_pcbdetach(inp);
INP_WUNLOCK(inp);
}
}
}
/*
* pru_detach() detaches the TCP protocol from the socket.
* If the protocol state is non-embryonic, then can't
* do this directly: have to initiate a pru_disconnect(),
* which may finish later; embryonic TCB's can just
* be discarded here.
*/
static void
tcp_usr_detach(struct socket *so)
{
struct inpcb *inp;
int rlock = 0;
struct epoch_tracker et;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_detach: inp == NULL"));
if (!INP_INFO_WLOCKED(&V_tcbinfo)) {
INP_INFO_RLOCK_ET(&V_tcbinfo, et);
rlock = 1;
}
INP_WLOCK(inp);
KASSERT(inp->inp_socket != NULL,
("tcp_usr_detach: inp_socket == NULL"));
tcp_detach(so, inp);
if (rlock)
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
}
#ifdef INET
/*
* Give the socket an address.
*/
static int
tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct sockaddr_in *sinp;
sinp = (struct sockaddr_in *)nam;
if (nam->sa_len != sizeof (*sinp))
return (EINVAL);
/*
* Must check for multicast addresses and disallow binding
* to them.
*/
if (sinp->sin_family == AF_INET &&
IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
return (EAFNOSUPPORT);
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_bind: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = EINVAL;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
INP_HASH_WLOCK(&V_tcbinfo);
error = in_pcbbind(inp, nam, td->td_ucred);
INP_HASH_WUNLOCK(&V_tcbinfo);
out:
TCPDEBUG2(PRU_BIND);
TCP_PROBE2(debug__user, tp, PRU_BIND);
INP_WUNLOCK(inp);
return (error);
}
#endif /* INET */
#ifdef INET6
static int
tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct sockaddr_in6 *sin6p;
sin6p = (struct sockaddr_in6 *)nam;
if (nam->sa_len != sizeof (*sin6p))
return (EINVAL);
/*
* Must check for multicast addresses and disallow binding
* to them.
*/
if (sin6p->sin6_family == AF_INET6 &&
IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
return (EAFNOSUPPORT);
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp6_usr_bind: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = EINVAL;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
INP_HASH_WLOCK(&V_tcbinfo);
inp->inp_vflag &= ~INP_IPV4;
inp->inp_vflag |= INP_IPV6;
#ifdef INET
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
inp->inp_vflag |= INP_IPV4;
else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
struct sockaddr_in sin;
in6_sin6_2_sin(&sin, sin6p);
if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
error = EAFNOSUPPORT;
INP_HASH_WUNLOCK(&V_tcbinfo);
goto out;
}
inp->inp_vflag |= INP_IPV4;
inp->inp_vflag &= ~INP_IPV6;
error = in_pcbbind(inp, (struct sockaddr *)&sin,
td->td_ucred);
INP_HASH_WUNLOCK(&V_tcbinfo);
goto out;
}
}
#endif
error = in6_pcbbind(inp, nam, td->td_ucred);
INP_HASH_WUNLOCK(&V_tcbinfo);
out:
TCPDEBUG2(PRU_BIND);
TCP_PROBE2(debug__user, tp, PRU_BIND);
INP_WUNLOCK(inp);
return (error);
}
#endif /* INET6 */
#ifdef INET
/*
* Prepare to accept connections.
*/
static int
tcp_usr_listen(struct socket *so, int backlog, struct thread *td)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_listen: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = EINVAL;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
SOCK_LOCK(so);
error = solisten_proto_check(so);
INP_HASH_WLOCK(&V_tcbinfo);
if (error == 0 && inp->inp_lport == 0)
error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
INP_HASH_WUNLOCK(&V_tcbinfo);
if (error == 0) {
tcp_state_change(tp, TCPS_LISTEN);
solisten_proto(so, backlog);
#ifdef TCP_OFFLOAD
if ((so->so_options & SO_NO_OFFLOAD) == 0)
tcp_offload_listen_start(tp);
#endif
}
SOCK_UNLOCK(so);
if (IS_FASTOPEN(tp->t_flags))
tp->t_tfo_pending = tcp_fastopen_alloc_counter();
out:
TCPDEBUG2(PRU_LISTEN);
TCP_PROBE2(debug__user, tp, PRU_LISTEN);
INP_WUNLOCK(inp);
return (error);
}
#endif /* INET */
#ifdef INET6
static int
tcp6_usr_listen(struct socket *so, int backlog, struct thread *td)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp6_usr_listen: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = EINVAL;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
SOCK_LOCK(so);
error = solisten_proto_check(so);
INP_HASH_WLOCK(&V_tcbinfo);
if (error == 0 && inp->inp_lport == 0) {
inp->inp_vflag &= ~INP_IPV4;
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
inp->inp_vflag |= INP_IPV4;
error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
}
INP_HASH_WUNLOCK(&V_tcbinfo);
if (error == 0) {
tcp_state_change(tp, TCPS_LISTEN);
solisten_proto(so, backlog);
#ifdef TCP_OFFLOAD
if ((so->so_options & SO_NO_OFFLOAD) == 0)
tcp_offload_listen_start(tp);
#endif
}
SOCK_UNLOCK(so);
if (IS_FASTOPEN(tp->t_flags))
tp->t_tfo_pending = tcp_fastopen_alloc_counter();
out:
TCPDEBUG2(PRU_LISTEN);
TCP_PROBE2(debug__user, tp, PRU_LISTEN);
INP_WUNLOCK(inp);
return (error);
}
#endif /* INET6 */
#ifdef INET
/*
* Initiate connection to peer.
* Create a template for use in transmissions on this connection.
* Enter SYN_SENT state, and mark socket as connecting.
* Start keep-alive timer, and seed output sequence space.
* Send initial segment on connection.
*/
static int
tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct sockaddr_in *sinp;
sinp = (struct sockaddr_in *)nam;
if (nam->sa_len != sizeof (*sinp))
return (EINVAL);
/*
* Must disallow TCP ``connections'' to multicast addresses.
*/
if (sinp->sin_family == AF_INET
&& IN_MULTICAST(ntohl(sinp->sin_addr.s_addr)))
return (EAFNOSUPPORT);
if ((error = prison_remote_ip4(td->td_ucred, &sinp->sin_addr)) != 0)
return (error);
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_connect: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & INP_TIMEWAIT) {
error = EADDRINUSE;
goto out;
}
if (inp->inp_flags & INP_DROPPED) {
error = ECONNREFUSED;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
if ((error = tcp_connect(tp, nam, td)) != 0)
goto out;
#ifdef TCP_OFFLOAD
if (registered_toedevs > 0 &&
(so->so_options & SO_NO_OFFLOAD) == 0 &&
(error = tcp_offload_connect(so, nam)) == 0)
goto out;
#endif
tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
error = tp->t_fb->tfb_tcp_output(tp);
out:
TCPDEBUG2(PRU_CONNECT);
TCP_PROBE2(debug__user, tp, PRU_CONNECT);
INP_WUNLOCK(inp);
return (error);
}
#endif /* INET */
#ifdef INET6
static int
tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct sockaddr_in6 *sin6p;
TCPDEBUG0;
sin6p = (struct sockaddr_in6 *)nam;
if (nam->sa_len != sizeof (*sin6p))
return (EINVAL);
/*
* Must disallow TCP ``connections'' to multicast addresses.
*/
if (sin6p->sin6_family == AF_INET6
&& IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr))
return (EAFNOSUPPORT);
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp6_usr_connect: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & INP_TIMEWAIT) {
error = EADDRINUSE;
goto out;
}
if (inp->inp_flags & INP_DROPPED) {
error = ECONNREFUSED;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
#ifdef INET
/*
* XXXRW: Some confusion: V4/V6 flags relate to binding, and
* therefore probably require the hash lock, which isn't held here.
* Is this a significant problem?
*/
if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
struct sockaddr_in sin;
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
error = EINVAL;
goto out;
}
if ((inp->inp_vflag & INP_IPV4) == 0) {
error = EAFNOSUPPORT;
goto out;
}
in6_sin6_2_sin(&sin, sin6p);
if (IN_MULTICAST(ntohl(sin.sin_addr.s_addr))) {
error = EAFNOSUPPORT;
goto out;
}
inp->inp_vflag |= INP_IPV4;
inp->inp_vflag &= ~INP_IPV6;
if ((error = prison_remote_ip4(td->td_ucred,
&sin.sin_addr)) != 0)
goto out;
if ((error = tcp_connect(tp, (struct sockaddr *)&sin, td)) != 0)
goto out;
#ifdef TCP_OFFLOAD
if (registered_toedevs > 0 &&
(so->so_options & SO_NO_OFFLOAD) == 0 &&
(error = tcp_offload_connect(so, nam)) == 0)
goto out;
#endif
error = tp->t_fb->tfb_tcp_output(tp);
goto out;
} else {
if ((inp->inp_vflag & INP_IPV6) == 0) {
error = EAFNOSUPPORT;
goto out;
}
}
#endif
inp->inp_vflag &= ~INP_IPV4;
inp->inp_vflag |= INP_IPV6;
inp->inp_inc.inc_flags |= INC_ISIPV6;
if ((error = prison_remote_ip6(td->td_ucred, &sin6p->sin6_addr)) != 0)
goto out;
if ((error = tcp6_connect(tp, nam, td)) != 0)
goto out;
#ifdef TCP_OFFLOAD
if (registered_toedevs > 0 &&
(so->so_options & SO_NO_OFFLOAD) == 0 &&
(error = tcp_offload_connect(so, nam)) == 0)
goto out;
#endif
tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
error = tp->t_fb->tfb_tcp_output(tp);
out:
TCPDEBUG2(PRU_CONNECT);
TCP_PROBE2(debug__user, tp, PRU_CONNECT);
INP_WUNLOCK(inp);
return (error);
}
#endif /* INET6 */
/*
* Initiate disconnect from peer.
* If connection never passed embryonic stage, just drop;
* else if don't need to let data drain, then can just drop anyways,
* else have to begin TCP shutdown process: mark socket disconnecting,
* drain unread data, state switch to reflect user close, and
* send segment (e.g. FIN) to peer. Socket will be really disconnected
* when peer sends FIN and acks ours.
*
* SHOULD IMPLEMENT LATER PRU_CONNECT VIA REALLOC TCPCB.
*/
static int
tcp_usr_disconnect(struct socket *so)
{
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct epoch_tracker et;
int error = 0;
TCPDEBUG0;
INP_INFO_RLOCK_ET(&V_tcbinfo, et);
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_disconnect: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & INP_TIMEWAIT)
goto out;
if (inp->inp_flags & INP_DROPPED) {
error = ECONNRESET;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
tcp_disconnect(tp);
out:
TCPDEBUG2(PRU_DISCONNECT);
TCP_PROBE2(debug__user, tp, PRU_DISCONNECT);
INP_WUNLOCK(inp);
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
return (error);
}
#ifdef INET
/*
* Accept a connection. Essentially all the work is done at higher levels;
* just return the address of the peer, storing through addr.
*/
static int
tcp_usr_accept(struct socket *so, struct sockaddr **nam)
{
int error = 0;
struct inpcb *inp = NULL;
struct tcpcb *tp = NULL;
struct in_addr addr;
in_port_t port = 0;
TCPDEBUG0;
if (so->so_state & SS_ISDISCONNECTED)
return (ECONNABORTED);
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_accept: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = ECONNABORTED;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
/*
* We inline in_getpeeraddr and COMMON_END here, so that we can
* copy the data of interest and defer the malloc until after we
* release the lock.
*/
port = inp->inp_fport;
addr = inp->inp_faddr;
out:
TCPDEBUG2(PRU_ACCEPT);
TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
INP_WUNLOCK(inp);
if (error == 0)
*nam = in_sockaddr(port, &addr);
return error;
}
#endif /* INET */
#ifdef INET6
static int
tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
{
struct inpcb *inp = NULL;
int error = 0;
struct tcpcb *tp = NULL;
struct in_addr addr;
struct in6_addr addr6;
struct epoch_tracker et;
in_port_t port = 0;
int v4 = 0;
TCPDEBUG0;
if (so->so_state & SS_ISDISCONNECTED)
return (ECONNABORTED);
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp6_usr_accept: inp == NULL"));
INP_INFO_RLOCK_ET(&V_tcbinfo, et);
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = ECONNABORTED;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
/*
* We inline in6_mapped_peeraddr and COMMON_END here, so that we can
* copy the data of interest and defer the malloc until after we
* release the lock.
*/
if (inp->inp_vflag & INP_IPV4) {
v4 = 1;
port = inp->inp_fport;
addr = inp->inp_faddr;
} else {
port = inp->inp_fport;
addr6 = inp->in6p_faddr;
}
out:
TCPDEBUG2(PRU_ACCEPT);
TCP_PROBE2(debug__user, tp, PRU_ACCEPT);
INP_WUNLOCK(inp);
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
if (error == 0) {
if (v4)
*nam = in6_v4mapsin6_sockaddr(port, &addr);
else
*nam = in6_sockaddr(port, &addr6);
}
return error;
}
#endif /* INET6 */
/*
* Mark the connection as being incapable of further output.
*/
static int
tcp_usr_shutdown(struct socket *so)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct epoch_tracker et;
TCPDEBUG0;
INP_INFO_RLOCK_ET(&V_tcbinfo, et);
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = ECONNRESET;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
socantsendmore(so);
tcp_usrclosed(tp);
if (!(inp->inp_flags & INP_DROPPED))
error = tp->t_fb->tfb_tcp_output(tp);
out:
TCPDEBUG2(PRU_SHUTDOWN);
TCP_PROBE2(debug__user, tp, PRU_SHUTDOWN);
INP_WUNLOCK(inp);
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
return (error);
}
/*
* After a receive, possibly send window update to peer.
*/
static int
tcp_usr_rcvd(struct socket *so, int flags)
{
struct inpcb *inp;
struct tcpcb *tp = NULL;
int error = 0;
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_rcvd: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = ECONNRESET;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
/*
* For passively-created TFO connections, don't attempt a window
* update while still in SYN_RECEIVED as this may trigger an early
* SYN|ACK. It is preferable to have the SYN|ACK be sent along with
* application response data, or failing that, when the DELACK timer
* expires.
*/
if (IS_FASTOPEN(tp->t_flags) &&
(tp->t_state == TCPS_SYN_RECEIVED))
goto out;
#ifdef TCP_OFFLOAD
if (tp->t_flags & TF_TOE)
tcp_offload_rcvd(tp);
else
#endif
tp->t_fb->tfb_tcp_output(tp);
out:
TCPDEBUG2(PRU_RCVD);
TCP_PROBE2(debug__user, tp, PRU_RCVD);
INP_WUNLOCK(inp);
return (error);
}
/*
* Do a send by putting data in output queue and updating urgent
* marker if URG set. Possibly send more data. Unlike the other
* pru_*() routines, the mbuf chains are our responsibility. We
* must either enqueue them or free them. The other pru_* routines
* generally are caller-frees.
*/
static int
tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
struct sockaddr *nam, struct mbuf *control, struct thread *td)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct epoch_tracker net_et;
#ifdef INET
#ifdef INET6
struct sockaddr_in sin;
#endif
struct sockaddr_in *sinp;
#endif
#ifdef INET6
int isipv6;
#endif
TCPDEBUG0;
/*
* We require the pcbinfo lock if we will close the socket as part of
* this call.
*/
if (flags & PRUS_EOF)
INP_INFO_RLOCK_ET(&V_tcbinfo, net_et);
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_send: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
if (control)
m_freem(control);
/*
* In case of PRUS_NOTREADY, tcp_usr_ready() is responsible
* for freeing memory.
*/
if (m && (flags & PRUS_NOTREADY) == 0)
m_freem(m);
error = ECONNRESET;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
if (nam != NULL && tp->t_state < TCPS_SYN_SENT) {
switch (nam->sa_family) {
#ifdef INET
case AF_INET:
sinp = (struct sockaddr_in *)nam;
if (sinp->sin_len != sizeof(struct sockaddr_in)) {
if (m)
m_freem(m);
error = EINVAL;
goto out;
}
if ((inp->inp_vflag & INP_IPV6) != 0) {
if (m)
m_freem(m);
error = EAFNOSUPPORT;
goto out;
}
if (IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
if (m)
m_freem(m);
error = EAFNOSUPPORT;
goto out;
}
if ((error = prison_remote_ip4(td->td_ucred,
&sinp->sin_addr))) {
if (m)
m_freem(m);
goto out;
}
#ifdef INET6
isipv6 = 0;
#endif
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
{
struct sockaddr_in6 *sin6p;
sin6p = (struct sockaddr_in6 *)nam;
if (sin6p->sin6_len != sizeof(struct sockaddr_in6)) {
if (m)
m_freem(m);
error = EINVAL;
goto out;
}
if (IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
if (m)
m_freem(m);
error = EAFNOSUPPORT;
goto out;
}
if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
#ifdef INET
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
error = EINVAL;
if (m)
m_freem(m);
goto out;
}
if ((inp->inp_vflag & INP_IPV4) == 0) {
error = EAFNOSUPPORT;
if (m)
m_freem(m);
goto out;
}
inp->inp_vflag &= ~INP_IPV6;
sinp = &sin;
in6_sin6_2_sin(sinp, sin6p);
if (IN_MULTICAST(
ntohl(sinp->sin_addr.s_addr))) {
error = EAFNOSUPPORT;
if (m)
m_freem(m);
goto out;
}
if ((error = prison_remote_ip4(td->td_ucred,
&sinp->sin_addr))) {
if (m)
m_freem(m);
goto out;
}
isipv6 = 0;
#else /* !INET */
error = EAFNOSUPPORT;
if (m)
m_freem(m);
goto out;
#endif /* INET */
} else {
if ((inp->inp_vflag & INP_IPV6) == 0) {
if (m)
m_freem(m);
error = EAFNOSUPPORT;
goto out;
}
inp->inp_vflag &= ~INP_IPV4;
inp->inp_inc.inc_flags |= INC_ISIPV6;
if ((error = prison_remote_ip6(td->td_ucred,
&sin6p->sin6_addr))) {
if (m)
m_freem(m);
goto out;
}
isipv6 = 1;
}
break;
}
#endif /* INET6 */
default:
if (m)
m_freem(m);
error = EAFNOSUPPORT;
goto out;
}
}
if (control) {
/* TCP doesn't do control messages (rights, creds, etc) */
if (control->m_len) {
m_freem(control);
if (m)
m_freem(m);
error = EINVAL;
goto out;
}
m_freem(control); /* empty control, just free it */
}
if (!(flags & PRUS_OOB)) {
sbappendstream(&so->so_snd, m, flags);
if (nam && tp->t_state < TCPS_SYN_SENT) {
/*
* Do implied connect if not yet connected,
* initialize window to default value, and
* initialize maxseg using peer's cached MSS.
*/
#ifdef INET6
if (isipv6)
error = tcp6_connect(tp, nam, td);
#endif /* INET6 */
#if defined(INET6) && defined(INET)
else
#endif
#ifdef INET
error = tcp_connect(tp,
(struct sockaddr *)sinp, td);
#endif
if (error)
goto out;
if (IS_FASTOPEN(tp->t_flags))
tcp_fastopen_connect(tp);
else {
tp->snd_wnd = TTCP_CLIENT_SND_WND;
tcp_mss(tp, -1);
}
}
if (flags & PRUS_EOF) {
/*
* Close the send side of the connection after
* the data is sent.
*/
INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
socantsendmore(so);
tcp_usrclosed(tp);
}
if (!(inp->inp_flags & INP_DROPPED) &&
!(flags & PRUS_NOTREADY)) {
if (flags & PRUS_MORETOCOME)
tp->t_flags |= TF_MORETOCOME;
error = tp->t_fb->tfb_tcp_output(tp);
if (flags & PRUS_MORETOCOME)
tp->t_flags &= ~TF_MORETOCOME;
}
} else {
/*
* XXXRW: PRUS_EOF not implemented with PRUS_OOB?
*/
SOCKBUF_LOCK(&so->so_snd);
if (sbspace(&so->so_snd) < -512) {
SOCKBUF_UNLOCK(&so->so_snd);
m_freem(m);
error = ENOBUFS;
goto out;
}
/*
* According to RFC961 (Assigned Protocols),
* the urgent pointer points to the last octet
* of urgent data. We continue, however,
* to consider it to indicate the first octet
* of data past the urgent section.
* Otherwise, snd_up should be one lower.
*/
sbappendstream_locked(&so->so_snd, m, flags);
SOCKBUF_UNLOCK(&so->so_snd);
if (nam && tp->t_state < TCPS_SYN_SENT) {
/*
* Do implied connect if not yet connected,
* initialize window to default value, and
* initialize maxseg using peer's cached MSS.
*/
/*
* Not going to contemplate SYN|URG
*/
if (IS_FASTOPEN(tp->t_flags))
tp->t_flags &= ~TF_FASTOPEN;
#ifdef INET6
if (isipv6)
error = tcp6_connect(tp, nam, td);
#endif /* INET6 */
#if defined(INET6) && defined(INET)
else
#endif
#ifdef INET
error = tcp_connect(tp,
(struct sockaddr *)sinp, td);
#endif
if (error)
goto out;
tp->snd_wnd = TTCP_CLIENT_SND_WND;
tcp_mss(tp, -1);
}
tp->snd_up = tp->snd_una + sbavail(&so->so_snd);
if (!(flags & PRUS_NOTREADY)) {
tp->t_flags |= TF_FORCEDATA;
error = tp->t_fb->tfb_tcp_output(tp);
tp->t_flags &= ~TF_FORCEDATA;
}
}
TCP_LOG_EVENT(tp, NULL,
&inp->inp_socket->so_rcv,
&inp->inp_socket->so_snd,
TCP_LOG_USERSEND, error,
0, NULL, false);
out:
TCPDEBUG2((flags & PRUS_OOB) ? PRU_SENDOOB :
((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
TCP_PROBE2(debug__user, tp, (flags & PRUS_OOB) ? PRU_SENDOOB :
((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
INP_WUNLOCK(inp);
if (flags & PRUS_EOF)
INP_INFO_RUNLOCK_ET(&V_tcbinfo, net_et);
return (error);
}
static int
tcp_usr_ready(struct socket *so, struct mbuf *m, int count)
{
struct inpcb *inp;
struct tcpcb *tp;
int error;
inp = sotoinpcb(so);
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
INP_WUNLOCK(inp);
mb_free_notready(m, count);
return (ECONNRESET);
}
tp = intotcpcb(inp);
SOCKBUF_LOCK(&so->so_snd);
error = sbready(&so->so_snd, m, count);
SOCKBUF_UNLOCK(&so->so_snd);
if (error == 0)
error = tp->t_fb->tfb_tcp_output(tp);
INP_WUNLOCK(inp);
return (error);
}
/*
* Abort the TCP. Drop the connection abruptly.
*/
static void
tcp_usr_abort(struct socket *so)
{
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct epoch_tracker et;
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_abort: inp == NULL"));
INP_INFO_RLOCK_ET(&V_tcbinfo, et);
INP_WLOCK(inp);
KASSERT(inp->inp_socket != NULL,
("tcp_usr_abort: inp_socket == NULL"));
/*
* If we still have full TCP state, and we're not dropped, drop.
*/
if (!(inp->inp_flags & INP_TIMEWAIT) &&
!(inp->inp_flags & INP_DROPPED)) {
tp = intotcpcb(inp);
TCPDEBUG1();
tp = tcp_drop(tp, ECONNABORTED);
if (tp == NULL)
goto dropped;
TCPDEBUG2(PRU_ABORT);
TCP_PROBE2(debug__user, tp, PRU_ABORT);
}
if (!(inp->inp_flags & INP_DROPPED)) {
SOCK_LOCK(so);
so->so_state |= SS_PROTOREF;
SOCK_UNLOCK(so);
inp->inp_flags |= INP_SOCKREF;
}
INP_WUNLOCK(inp);
dropped:
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
}
/*
* TCP socket is closed. Start friendly disconnect.
*/
static void
tcp_usr_close(struct socket *so)
{
struct inpcb *inp;
struct tcpcb *tp = NULL;
struct epoch_tracker et;
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_close: inp == NULL"));
INP_INFO_RLOCK_ET(&V_tcbinfo, et);
INP_WLOCK(inp);
KASSERT(inp->inp_socket != NULL,
("tcp_usr_close: inp_socket == NULL"));
/*
* If we still have full TCP state, and we're not dropped, initiate
* a disconnect.
*/
if (!(inp->inp_flags & INP_TIMEWAIT) &&
!(inp->inp_flags & INP_DROPPED)) {
tp = intotcpcb(inp);
TCPDEBUG1();
tcp_disconnect(tp);
TCPDEBUG2(PRU_CLOSE);
TCP_PROBE2(debug__user, tp, PRU_CLOSE);
}
if (!(inp->inp_flags & INP_DROPPED)) {
SOCK_LOCK(so);
so->so_state |= SS_PROTOREF;
SOCK_UNLOCK(so);
inp->inp_flags |= INP_SOCKREF;
}
INP_WUNLOCK(inp);
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
}
/*
* Receive out-of-band data.
*/
static int
tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
{
int error = 0;
struct inpcb *inp;
struct tcpcb *tp = NULL;
TCPDEBUG0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_usr_rcvoob: inp == NULL"));
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
error = ECONNRESET;
goto out;
}
tp = intotcpcb(inp);
TCPDEBUG1();
if ((so->so_oobmark == 0 &&
(so->so_rcv.sb_state & SBS_RCVATMARK) == 0) ||
so->so_options & SO_OOBINLINE ||
tp->t_oobflags & TCPOOB_HADDATA) {
error = EINVAL;
goto out;
}
if ((tp->t_oobflags & TCPOOB_HAVEDATA) == 0) {
error = EWOULDBLOCK;
goto out;
}
m->m_len = 1;
*mtod(m, caddr_t) = tp->t_iobc;
if ((flags & MSG_PEEK) == 0)
tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
out:
TCPDEBUG2(PRU_RCVOOB);
TCP_PROBE2(debug__user, tp, PRU_RCVOOB);
INP_WUNLOCK(inp);
return (error);
}
#ifdef INET
struct pr_usrreqs tcp_usrreqs = {
.pru_abort = tcp_usr_abort,
.pru_accept = tcp_usr_accept,
.pru_attach = tcp_usr_attach,
.pru_bind = tcp_usr_bind,
.pru_connect = tcp_usr_connect,
.pru_control = in_control,
.pru_detach = tcp_usr_detach,
.pru_disconnect = tcp_usr_disconnect,
.pru_listen = tcp_usr_listen,
.pru_peeraddr = in_getpeeraddr,
.pru_rcvd = tcp_usr_rcvd,
.pru_rcvoob = tcp_usr_rcvoob,
.pru_send = tcp_usr_send,
.pru_ready = tcp_usr_ready,
.pru_shutdown = tcp_usr_shutdown,
.pru_sockaddr = in_getsockaddr,
.pru_sosetlabel = in_pcbsosetlabel,
.pru_close = tcp_usr_close,
};
#endif /* INET */
#ifdef INET6
struct pr_usrreqs tcp6_usrreqs = {
.pru_abort = tcp_usr_abort,
.pru_accept = tcp6_usr_accept,
.pru_attach = tcp_usr_attach,
.pru_bind = tcp6_usr_bind,
.pru_connect = tcp6_usr_connect,
.pru_control = in6_control,
.pru_detach = tcp_usr_detach,
.pru_disconnect = tcp_usr_disconnect,
.pru_listen = tcp6_usr_listen,
.pru_peeraddr = in6_mapped_peeraddr,
.pru_rcvd = tcp_usr_rcvd,
.pru_rcvoob = tcp_usr_rcvoob,
.pru_send = tcp_usr_send,
.pru_ready = tcp_usr_ready,
.pru_shutdown = tcp_usr_shutdown,
.pru_sockaddr = in6_mapped_sockaddr,
.pru_sosetlabel = in_pcbsosetlabel,
.pru_close = tcp_usr_close,
};
#endif /* INET6 */
#ifdef INET
/*
* Common subroutine to open a TCP connection to remote host specified
* by struct sockaddr_in in mbuf *nam. Call in_pcbbind to assign a local
* port number if needed. Call in_pcbconnect_setup to do the routing and
* to choose a local host address (interface). If there is an existing
* incarnation of the same connection in TIME-WAIT state and if the remote
* host was sending CC options and if the connection duration was < MSL, then
* truncate the previous TIME-WAIT state and proceed.
* Initialize connection parameters and enter SYN-SENT state.
*/
static int
tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
{
struct inpcb *inp = tp->t_inpcb, *oinp;
struct socket *so = inp->inp_socket;
struct in_addr laddr;
u_short lport;
int error;
INP_WLOCK_ASSERT(inp);
INP_HASH_WLOCK(&V_tcbinfo);
if (inp->inp_lport == 0) {
error = in_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
if (error)
goto out;
}
/*
* Cannot simply call in_pcbconnect, because there might be an
* earlier incarnation of this same connection still in
* TIME_WAIT state, creating an ADDRINUSE error.
*/
laddr = inp->inp_laddr;
lport = inp->inp_lport;
error = in_pcbconnect_setup(inp, nam, &laddr.s_addr, &lport,
&inp->inp_faddr.s_addr, &inp->inp_fport, &oinp, td->td_ucred);
if (error && oinp == NULL)
goto out;
if (oinp) {
error = EADDRINUSE;
goto out;
}
inp->inp_laddr = laddr;
in_pcbrehash(inp);
INP_HASH_WUNLOCK(&V_tcbinfo);
/*
* Compute window scaling to request:
* Scale to fit into sweet spot. See tcp_syncache.c.
* XXX: This should move to tcp_output().
*/
while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
(TCP_MAXWIN << tp->request_r_scale) < sb_max)
tp->request_r_scale++;
soisconnecting(so);
TCPSTAT_INC(tcps_connattempt);
tcp_state_change(tp, TCPS_SYN_SENT);
tp->iss = tcp_new_isn(&inp->inp_inc);
if (tp->t_flags & TF_REQ_TSTMP)
tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc);
tcp_sendseqinit(tp);
return 0;
out:
INP_HASH_WUNLOCK(&V_tcbinfo);
return (error);
}
#endif /* INET */
#ifdef INET6
static int
tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct thread *td)
{
struct inpcb *inp = tp->t_inpcb;
int error;
INP_WLOCK_ASSERT(inp);
INP_HASH_WLOCK(&V_tcbinfo);
if (inp->inp_lport == 0) {
error = in6_pcbbind(inp, (struct sockaddr *)0, td->td_ucred);
if (error)
goto out;
}
error = in6_pcbconnect(inp, nam, td->td_ucred);
if (error != 0)
goto out;
INP_HASH_WUNLOCK(&V_tcbinfo);
/* Compute window scaling to request. */
while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
(TCP_MAXWIN << tp->request_r_scale) < sb_max)
tp->request_r_scale++;
soisconnecting(inp->inp_socket);
TCPSTAT_INC(tcps_connattempt);
tcp_state_change(tp, TCPS_SYN_SENT);
tp->iss = tcp_new_isn(&inp->inp_inc);
if (tp->t_flags & TF_REQ_TSTMP)
tp->ts_offset = tcp_new_ts_offset(&inp->inp_inc);
tcp_sendseqinit(tp);
return 0;
out:
INP_HASH_WUNLOCK(&V_tcbinfo);
return error;
}
#endif /* INET6 */
/*
* Export TCP internal state information via a struct tcp_info, based on the
* Linux 2.6 API. Not ABI compatible as our constants are mapped differently
* (TCP state machine, etc). We export all information using FreeBSD-native
* constants -- for example, the numeric values for tcpi_state will differ
* from Linux.
*/
static void
tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
{
INP_WLOCK_ASSERT(tp->t_inpcb);
bzero(ti, sizeof(*ti));
ti->tcpi_state = tp->t_state;
if ((tp->t_flags & TF_REQ_TSTMP) && (tp->t_flags & TF_RCVD_TSTMP))
ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
if (tp->t_flags & TF_SACK_PERMIT)
ti->tcpi_options |= TCPI_OPT_SACK;
if ((tp->t_flags & TF_REQ_SCALE) && (tp->t_flags & TF_RCVD_SCALE)) {
ti->tcpi_options |= TCPI_OPT_WSCALE;
ti->tcpi_snd_wscale = tp->snd_scale;
ti->tcpi_rcv_wscale = tp->rcv_scale;
}
if (tp->t_flags & TF_ECN_PERMIT)
ti->tcpi_options |= TCPI_OPT_ECN;
ti->tcpi_rto = tp->t_rxtcur * tick;
ti->tcpi_last_data_recv = ((uint32_t)ticks - tp->t_rcvtime) * tick;
ti->tcpi_rtt = ((u_int64_t)tp->t_srtt * tick) >> TCP_RTT_SHIFT;
ti->tcpi_rttvar = ((u_int64_t)tp->t_rttvar * tick) >> TCP_RTTVAR_SHIFT;
ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
ti->tcpi_snd_cwnd = tp->snd_cwnd;
/*
* FreeBSD-specific extension fields for tcp_info.
*/
ti->tcpi_rcv_space = tp->rcv_wnd;
ti->tcpi_rcv_nxt = tp->rcv_nxt;
ti->tcpi_snd_wnd = tp->snd_wnd;
ti->tcpi_snd_bwnd = 0; /* Unused, kept for compat. */
ti->tcpi_snd_nxt = tp->snd_nxt;
ti->tcpi_snd_mss = tp->t_maxseg;
ti->tcpi_rcv_mss = tp->t_maxseg;
ti->tcpi_snd_rexmitpack = tp->t_sndrexmitpack;
ti->tcpi_rcv_ooopack = tp->t_rcvoopack;
ti->tcpi_snd_zerowin = tp->t_sndzerowin;
#ifdef TCP_OFFLOAD
if (tp->t_flags & TF_TOE) {
ti->tcpi_options |= TCPI_OPT_TOE;
tcp_offload_tcp_info(tp, ti);
}
#endif
}
/*
* tcp_ctloutput() must drop the inpcb lock before performing copyin on
* socket option arguments. When it re-acquires the lock after the copy, it
* has to revalidate that the connection is still valid for the socket
* option.
*/
#define INP_WLOCK_RECHECK_CLEANUP(inp, cleanup) do { \
INP_WLOCK(inp); \
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) { \
INP_WUNLOCK(inp); \
cleanup; \
return (ECONNRESET); \
} \
tp = intotcpcb(inp); \
} while(0)
#define INP_WLOCK_RECHECK(inp) INP_WLOCK_RECHECK_CLEANUP((inp), /* noop */)
int
tcp_ctloutput(struct socket *so, struct sockopt *sopt)
{
int error;
struct inpcb *inp;
struct tcpcb *tp;
struct tcp_function_block *blk;
struct tcp_function_set fsn;
error = 0;
inp = sotoinpcb(so);
KASSERT(inp != NULL, ("tcp_ctloutput: inp == NULL"));
if (sopt->sopt_level != IPPROTO_TCP) {
#ifdef INET6
if (inp->inp_vflag & INP_IPV6PROTO) {
error = ip6_ctloutput(so, sopt);
/*
* In case of the IPV6_USE_MIN_MTU socket option,
* the INC_IPV6MINMTU flag to announce a corresponding
* MSS during the initial handshake.
* If the TCP connection is not in the front states,
* just reduce the MSS being used.
* This avoids the sending of TCP segments which will
* be fragmented at the IPv6 layer.
*/
if ((error == 0) &&
(sopt->sopt_dir == SOPT_SET) &&
(sopt->sopt_level == IPPROTO_IPV6) &&
(sopt->sopt_name == IPV6_USE_MIN_MTU)) {
INP_WLOCK(inp);
if ((inp->inp_flags &
(INP_TIMEWAIT | INP_DROPPED))) {
INP_WUNLOCK(inp);
return (ECONNRESET);
}
inp->inp_inc.inc_flags |= INC_IPV6MINMTU;
tp = intotcpcb(inp);
if ((tp->t_state >= TCPS_SYN_SENT) &&
(inp->inp_inc.inc_flags & INC_ISIPV6)) {
struct ip6_pktopts *opt;
opt = inp->in6p_outputopts;
if ((opt != NULL) &&
(opt->ip6po_minmtu ==
IP6PO_MINMTU_ALL)) {
if (tp->t_maxseg > TCP6_MSS) {
tp->t_maxseg = TCP6_MSS;
}
}
}
INP_WUNLOCK(inp);
}
}
#endif /* INET6 */
#if defined(INET6) && defined(INET)
else
#endif
#ifdef INET
{
error = ip_ctloutput(so, sopt);
}
#endif
return (error);
}
INP_WLOCK(inp);
if (inp->inp_flags & (INP_TIMEWAIT | INP_DROPPED)) {
INP_WUNLOCK(inp);
return (ECONNRESET);
}
tp = intotcpcb(inp);
/*
* Protect the TCP option TCP_FUNCTION_BLK so
* that a sub-function can *never* overwrite this.
*/
if ((sopt->sopt_dir == SOPT_SET) &&
(sopt->sopt_name == TCP_FUNCTION_BLK)) {
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &fsn, sizeof fsn,
sizeof fsn);
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
blk = find_and_ref_tcp_functions(&fsn);
if (blk == NULL) {
INP_WUNLOCK(inp);
return (ENOENT);
}
if (tp->t_fb == blk) {
/* You already have this */
refcount_release(&blk->tfb_refcnt);
INP_WUNLOCK(inp);
return (0);
}
if (tp->t_state != TCPS_CLOSED) {
/*
* The user has advanced the state
* past the initial point, we may not
* be able to switch.
*/
if (blk->tfb_tcp_handoff_ok != NULL) {
/*
* Does the stack provide a
* query mechanism, if so it may
* still be possible?
*/
error = (*blk->tfb_tcp_handoff_ok)(tp);
} else
error = EINVAL;
if (error) {
refcount_release(&blk->tfb_refcnt);
INP_WUNLOCK(inp);
return(error);
}
}
if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
refcount_release(&blk->tfb_refcnt);
INP_WUNLOCK(inp);
return (ENOENT);
}
/*
* Release the old refcnt, the
* lookup acquired a ref on the
* new one already.
*/
if (tp->t_fb->tfb_tcp_fb_fini) {
/*
* Tell the stack to cleanup with 0 i.e.
* the tcb is not going away.
*/
(*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
}
#ifdef TCPHPTS
/* Assure that we are not on any hpts */
tcp_hpts_remove(tp->t_inpcb, HPTS_REMOVE_ALL);
#endif
if (blk->tfb_tcp_fb_init) {
error = (*blk->tfb_tcp_fb_init)(tp);
if (error) {
refcount_release(&blk->tfb_refcnt);
if (tp->t_fb->tfb_tcp_fb_init) {
if((*tp->t_fb->tfb_tcp_fb_init)(tp) != 0) {
/* Fall back failed, drop the connection */
INP_WUNLOCK(inp);
soabort(so);
return(error);
}
}
goto err_out;
}
}
refcount_release(&tp->t_fb->tfb_refcnt);
tp->t_fb = blk;
#ifdef TCP_OFFLOAD
if (tp->t_flags & TF_TOE) {
tcp_offload_ctloutput(tp, sopt->sopt_dir,
sopt->sopt_name);
}
#endif
err_out:
INP_WUNLOCK(inp);
return (error);
} else if ((sopt->sopt_dir == SOPT_GET) &&
(sopt->sopt_name == TCP_FUNCTION_BLK)) {
strncpy(fsn.function_set_name, tp->t_fb->tfb_tcp_block_name,
TCP_FUNCTION_NAME_LEN_MAX);
fsn.function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
fsn.pcbcnt = tp->t_fb->tfb_refcnt;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &fsn, sizeof fsn);
return (error);
}
/* Pass in the INP locked, called must unlock it */
return (tp->t_fb->tfb_tcp_ctloutput(so, sopt, inp, tp));
}
/*
* If this assert becomes untrue, we need to change the size of the buf
* variable in tcp_default_ctloutput().
*/
#ifdef CTASSERT
CTASSERT(TCP_CA_NAME_MAX <= TCP_LOG_ID_LEN);
CTASSERT(TCP_LOG_REASON_LEN <= TCP_LOG_ID_LEN);
#endif
int
tcp_default_ctloutput(struct socket *so, struct sockopt *sopt, struct inpcb *inp, struct tcpcb *tp)
{
int error, opt, optval;
u_int ui;
struct tcp_info ti;
struct cc_algo *algo;
char *pbuf, buf[TCP_LOG_ID_LEN];
size_t len;
/*
* For TCP_CCALGOOPT forward the control to CC module, for both
* SOPT_SET and SOPT_GET.
*/
switch (sopt->sopt_name) {
case TCP_CCALGOOPT:
INP_WUNLOCK(inp);
if (sopt->sopt_valsize > CC_ALGOOPT_LIMIT)
return (EINVAL);
pbuf = malloc(sopt->sopt_valsize, M_TEMP, M_WAITOK | M_ZERO);
error = sooptcopyin(sopt, pbuf, sopt->sopt_valsize,
sopt->sopt_valsize);
if (error) {
free(pbuf, M_TEMP);
return (error);
}
INP_WLOCK_RECHECK_CLEANUP(inp, free(pbuf, M_TEMP));
if (CC_ALGO(tp)->ctl_output != NULL)
error = CC_ALGO(tp)->ctl_output(tp->ccv, sopt, pbuf);
else
error = ENOENT;
INP_WUNLOCK(inp);
if (error == 0 && sopt->sopt_dir == SOPT_GET)
error = sooptcopyout(sopt, pbuf, sopt->sopt_valsize);
free(pbuf, M_TEMP);
return (error);
}
switch (sopt->sopt_dir) {
case SOPT_SET:
switch (sopt->sopt_name) {
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
case TCP_MD5SIG:
if (!TCPMD5_ENABLED()) {
INP_WUNLOCK(inp);
return (ENOPROTOOPT);
}
error = TCPMD5_PCBCTL(inp, sopt);
if (error)
return (error);
goto unlock_and_done;
#endif /* IPSEC */
case TCP_NODELAY:
case TCP_NOOPT:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &optval, sizeof optval,
sizeof optval);
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
switch (sopt->sopt_name) {
case TCP_NODELAY:
opt = TF_NODELAY;
break;
case TCP_NOOPT:
opt = TF_NOOPT;
break;
default:
opt = 0; /* dead code to fool gcc */
break;
}
if (optval)
tp->t_flags |= opt;
else
tp->t_flags &= ~opt;
unlock_and_done:
#ifdef TCP_OFFLOAD
if (tp->t_flags & TF_TOE) {
tcp_offload_ctloutput(tp, sopt->sopt_dir,
sopt->sopt_name);
}
#endif
INP_WUNLOCK(inp);
break;
case TCP_NOPUSH:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &optval, sizeof optval,
sizeof optval);
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
if (optval)
tp->t_flags |= TF_NOPUSH;
else if (tp->t_flags & TF_NOPUSH) {
tp->t_flags &= ~TF_NOPUSH;
if (TCPS_HAVEESTABLISHED(tp->t_state))
error = tp->t_fb->tfb_tcp_output(tp);
}
goto unlock_and_done;
case TCP_MAXSEG:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &optval, sizeof optval,
sizeof optval);
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
if (optval > 0 && optval <= tp->t_maxseg &&
optval + 40 >= V_tcp_minmss)
tp->t_maxseg = optval;
else
error = EINVAL;
goto unlock_and_done;
case TCP_INFO:
INP_WUNLOCK(inp);
error = EINVAL;
break;
case TCP_CONGESTION:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, buf, TCP_CA_NAME_MAX - 1, 1);
if (error)
break;
buf[sopt->sopt_valsize] = '\0';
INP_WLOCK_RECHECK(inp);
CC_LIST_RLOCK();
STAILQ_FOREACH(algo, &cc_list, entries)
if (strncmp(buf, algo->name,
TCP_CA_NAME_MAX) == 0)
break;
CC_LIST_RUNLOCK();
if (algo == NULL) {
INP_WUNLOCK(inp);
error = EINVAL;
break;
}
/*
* We hold a write lock over the tcb so it's safe to
* do these things without ordering concerns.
*/
if (CC_ALGO(tp)->cb_destroy != NULL)
CC_ALGO(tp)->cb_destroy(tp->ccv);
CC_DATA(tp) = NULL;
CC_ALGO(tp) = algo;
/*
* If something goes pear shaped initialising the new
* algo, fall back to newreno (which does not
* require initialisation).
*/
if (algo->cb_init != NULL &&
algo->cb_init(tp->ccv) != 0) {
CC_ALGO(tp) = &newreno_cc_algo;
/*
* The only reason init should fail is
* because of malloc.
*/
error = ENOMEM;
}
INP_WUNLOCK(inp);
break;
case TCP_KEEPIDLE:
case TCP_KEEPINTVL:
case TCP_KEEPINIT:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
if (error)
return (error);
if (ui > (UINT_MAX / hz)) {
error = EINVAL;
break;
}
ui *= hz;
INP_WLOCK_RECHECK(inp);
switch (sopt->sopt_name) {
case TCP_KEEPIDLE:
tp->t_keepidle = ui;
/*
* XXX: better check current remaining
* timeout and "merge" it with new value.
*/
if ((tp->t_state > TCPS_LISTEN) &&
(tp->t_state <= TCPS_CLOSING))
tcp_timer_activate(tp, TT_KEEP,
TP_KEEPIDLE(tp));
break;
case TCP_KEEPINTVL:
tp->t_keepintvl = ui;
if ((tp->t_state == TCPS_FIN_WAIT_2) &&
(TP_MAXIDLE(tp) > 0))
tcp_timer_activate(tp, TT_2MSL,
TP_MAXIDLE(tp));
break;
case TCP_KEEPINIT:
tp->t_keepinit = ui;
if (tp->t_state == TCPS_SYN_RECEIVED ||
tp->t_state == TCPS_SYN_SENT)
tcp_timer_activate(tp, TT_KEEP,
TP_KEEPINIT(tp));
break;
}
goto unlock_and_done;
case TCP_KEEPCNT:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &ui, sizeof(ui), sizeof(ui));
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
tp->t_keepcnt = ui;
if ((tp->t_state == TCPS_FIN_WAIT_2) &&
(TP_MAXIDLE(tp) > 0))
tcp_timer_activate(tp, TT_2MSL,
TP_MAXIDLE(tp));
goto unlock_and_done;
#ifdef TCPPCAP
case TCP_PCAP_OUT:
case TCP_PCAP_IN:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &optval, sizeof optval,
sizeof optval);
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
if (optval >= 0)
tcp_pcap_set_sock_max(TCP_PCAP_OUT ?
&(tp->t_outpkts) : &(tp->t_inpkts),
optval);
else
error = EINVAL;
goto unlock_and_done;
#endif
case TCP_FASTOPEN: {
struct tcp_fastopen tfo_optval;
INP_WUNLOCK(inp);
if (!V_tcp_fastopen_client_enable &&
!V_tcp_fastopen_server_enable)
return (EPERM);
error = sooptcopyin(sopt, &tfo_optval,
sizeof(tfo_optval), sizeof(int));
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
if (tfo_optval.enable) {
if (tp->t_state == TCPS_LISTEN) {
if (!V_tcp_fastopen_server_enable) {
error = EPERM;
goto unlock_and_done;
}
tp->t_flags |= TF_FASTOPEN;
if (tp->t_tfo_pending == NULL)
tp->t_tfo_pending =
tcp_fastopen_alloc_counter();
} else {
/*
* If a pre-shared key was provided,
* stash it in the client cookie
* field of the tcpcb for use during
* connect.
*/
if (sopt->sopt_valsize ==
sizeof(tfo_optval)) {
memcpy(tp->t_tfo_cookie.client,
tfo_optval.psk,
TCP_FASTOPEN_PSK_LEN);
tp->t_tfo_client_cookie_len =
TCP_FASTOPEN_PSK_LEN;
}
tp->t_flags |= TF_FASTOPEN;
}
} else
tp->t_flags &= ~TF_FASTOPEN;
goto unlock_and_done;
}
#ifdef TCP_BLACKBOX
case TCP_LOG:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, &optval, sizeof optval,
sizeof optval);
if (error)
return (error);
INP_WLOCK_RECHECK(inp);
error = tcp_log_state_change(tp, optval);
goto unlock_and_done;
case TCP_LOGBUF:
INP_WUNLOCK(inp);
error = EINVAL;
break;
case TCP_LOGID:
INP_WUNLOCK(inp);
error = sooptcopyin(sopt, buf, TCP_LOG_ID_LEN - 1, 0);
if (error)
break;
buf[sopt->sopt_valsize] = '\0';
INP_WLOCK_RECHECK(inp);
error = tcp_log_set_id(tp, buf);
/* tcp_log_set_id() unlocks the INP. */
break;
case TCP_LOGDUMP:
case TCP_LOGDUMPID:
INP_WUNLOCK(inp);
error =
sooptcopyin(sopt, buf, TCP_LOG_REASON_LEN - 1, 0);
if (error)
break;
buf[sopt->sopt_valsize] = '\0';
INP_WLOCK_RECHECK(inp);
if (sopt->sopt_name == TCP_LOGDUMP) {
error = tcp_log_dump_tp_logbuf(tp, buf,
M_WAITOK, true);
INP_WUNLOCK(inp);
} else {
tcp_log_dump_tp_bucket_logbufs(tp, buf);
/*
* tcp_log_dump_tp_bucket_logbufs() drops the
* INP lock.
*/
}
break;
#endif
default:
INP_WUNLOCK(inp);
error = ENOPROTOOPT;
break;
}
break;
case SOPT_GET:
tp = intotcpcb(inp);
switch (sopt->sopt_name) {
#if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
case TCP_MD5SIG:
if (!TCPMD5_ENABLED()) {
INP_WUNLOCK(inp);
return (ENOPROTOOPT);
}
error = TCPMD5_PCBCTL(inp, sopt);
break;
#endif
case TCP_NODELAY:
optval = tp->t_flags & TF_NODELAY;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof optval);
break;
case TCP_MAXSEG:
optval = tp->t_maxseg;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof optval);
break;
case TCP_NOOPT:
optval = tp->t_flags & TF_NOOPT;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof optval);
break;
case TCP_NOPUSH:
optval = tp->t_flags & TF_NOPUSH;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof optval);
break;
case TCP_INFO:
tcp_fill_info(tp, &ti);
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &ti, sizeof ti);
break;
case TCP_CONGESTION:
len = strlcpy(buf, CC_ALGO(tp)->name, TCP_CA_NAME_MAX);
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, buf, len + 1);
break;
case TCP_KEEPIDLE:
case TCP_KEEPINTVL:
case TCP_KEEPINIT:
case TCP_KEEPCNT:
switch (sopt->sopt_name) {
case TCP_KEEPIDLE:
ui = TP_KEEPIDLE(tp) / hz;
break;
case TCP_KEEPINTVL:
ui = TP_KEEPINTVL(tp) / hz;
break;
case TCP_KEEPINIT:
ui = TP_KEEPINIT(tp) / hz;
break;
case TCP_KEEPCNT:
ui = TP_KEEPCNT(tp);
break;
}
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &ui, sizeof(ui));
break;
#ifdef TCPPCAP
case TCP_PCAP_OUT:
case TCP_PCAP_IN:
optval = tcp_pcap_get_sock_max(TCP_PCAP_OUT ?
&(tp->t_outpkts) : &(tp->t_inpkts));
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof optval);
break;
#endif
case TCP_FASTOPEN:
optval = tp->t_flags & TF_FASTOPEN;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof optval);
break;
#ifdef TCP_BLACKBOX
case TCP_LOG:
optval = tp->t_logstate;
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, &optval, sizeof(optval));
break;
case TCP_LOGBUF:
/* tcp_log_getlogbuf() does INP_WUNLOCK(inp) */
error = tcp_log_getlogbuf(sopt, tp);
break;
case TCP_LOGID:
len = tcp_log_get_id(tp, buf);
INP_WUNLOCK(inp);
error = sooptcopyout(sopt, buf, len + 1);
break;
case TCP_LOGDUMP:
case TCP_LOGDUMPID:
INP_WUNLOCK(inp);
error = EINVAL;
break;
#endif
default:
INP_WUNLOCK(inp);
error = ENOPROTOOPT;
break;
}
break;
}
return (error);
}
#undef INP_WLOCK_RECHECK
#undef INP_WLOCK_RECHECK_CLEANUP
/*
* Attach TCP protocol to socket, allocating
* internet protocol control block, tcp control block,
* bufer space, and entering LISTEN state if to accept connections.
*/
static int
tcp_attach(struct socket *so)
{
struct tcpcb *tp;
struct inpcb *inp;
struct epoch_tracker et;
int error;
if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
error = soreserve(so, V_tcp_sendspace, V_tcp_recvspace);
if (error)
return (error);
}
so->so_rcv.sb_flags |= SB_AUTOSIZE;
so->so_snd.sb_flags |= SB_AUTOSIZE;
INP_INFO_RLOCK_ET(&V_tcbinfo, et);
error = in_pcballoc(so, &V_tcbinfo);
if (error) {
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
return (error);
}
inp = sotoinpcb(so);
#ifdef INET6
if (inp->inp_vflag & INP_IPV6PROTO) {
inp->inp_vflag |= INP_IPV6;
if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
inp->inp_vflag |= INP_IPV4;
inp->in6p_hops = -1; /* use kernel default */
}
else
#endif
inp->inp_vflag |= INP_IPV4;
tp = tcp_newtcpcb(inp);
if (tp == NULL) {
in_pcbdetach(inp);
in_pcbfree(inp);
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
return (ENOBUFS);
}
tp->t_state = TCPS_CLOSED;
INP_WUNLOCK(inp);
INP_INFO_RUNLOCK_ET(&V_tcbinfo, et);
TCPSTATES_INC(TCPS_CLOSED);
return (0);
}
/*
* Initiate (or continue) disconnect.
* If embryonic state, just send reset (once).
* If in ``let data drain'' option and linger null, just drop.
* Otherwise (hard), mark socket disconnecting and drop
* current input data; switch states based on user close, and
* send segment to peer (with FIN).
*/
static void
tcp_disconnect(struct tcpcb *tp)
{
struct inpcb *inp = tp->t_inpcb;
struct socket *so = inp->inp_socket;
INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
INP_WLOCK_ASSERT(inp);
/*
* Neither tcp_close() nor tcp_drop() should return NULL, as the
* socket is still open.
*/
if (tp->t_state < TCPS_ESTABLISHED &&
!(tp->t_state > TCPS_LISTEN && IS_FASTOPEN(tp->t_flags))) {
tp = tcp_close(tp);
KASSERT(tp != NULL,
("tcp_disconnect: tcp_close() returned NULL"));
} else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
tp = tcp_drop(tp, 0);
KASSERT(tp != NULL,
("tcp_disconnect: tcp_drop() returned NULL"));
} else {
soisdisconnecting(so);
sbflush(&so->so_rcv);
tcp_usrclosed(tp);
if (!(inp->inp_flags & INP_DROPPED))
tp->t_fb->tfb_tcp_output(tp);
}
}
/*
* User issued close, and wish to trail through shutdown states:
* if never received SYN, just forget it. If got a SYN from peer,
* but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
* If already got a FIN from peer, then almost done; go to LAST_ACK
* state. In all other cases, have already sent FIN to peer (e.g.
* after PRU_SHUTDOWN), and just have to play tedious game waiting
* for peer to send FIN or not respond to keep-alives, etc.
* We can let the user exit from the close as soon as the FIN is acked.
*/
static void
tcp_usrclosed(struct tcpcb *tp)
{
INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
INP_WLOCK_ASSERT(tp->t_inpcb);
switch (tp->t_state) {
case TCPS_LISTEN:
#ifdef TCP_OFFLOAD
tcp_offload_listen_stop(tp);
#endif
tcp_state_change(tp, TCPS_CLOSED);
/* FALLTHROUGH */
case TCPS_CLOSED:
tp = tcp_close(tp);
/*
* tcp_close() should never return NULL here as the socket is
* still open.
*/
KASSERT(tp != NULL,
("tcp_usrclosed: tcp_close() returned NULL"));
break;
case TCPS_SYN_SENT:
case TCPS_SYN_RECEIVED:
tp->t_flags |= TF_NEEDFIN;
break;
case TCPS_ESTABLISHED:
tcp_state_change(tp, TCPS_FIN_WAIT_1);
break;
case TCPS_CLOSE_WAIT:
tcp_state_change(tp, TCPS_LAST_ACK);
break;
}
if (tp->t_state >= TCPS_FIN_WAIT_2) {
soisdisconnected(tp->t_inpcb->inp_socket);
/* Prevent the connection hanging in FIN_WAIT_2 forever. */
if (tp->t_state == TCPS_FIN_WAIT_2) {
int timeout;
timeout = (tcp_fast_finwait2_recycle) ?
tcp_finwait2_timeout : TP_MAXIDLE(tp);
tcp_timer_activate(tp, TT_2MSL, timeout);
}
}
}
#ifdef DDB
static void
db_print_indent(int indent)
{
int i;
for (i = 0; i < indent; i++)
db_printf(" ");
}
static void
db_print_tstate(int t_state)
{
switch (t_state) {
case TCPS_CLOSED:
db_printf("TCPS_CLOSED");
return;
case TCPS_LISTEN:
db_printf("TCPS_LISTEN");
return;
case TCPS_SYN_SENT:
db_printf("TCPS_SYN_SENT");
return;
case TCPS_SYN_RECEIVED:
db_printf("TCPS_SYN_RECEIVED");
return;
case TCPS_ESTABLISHED:
db_printf("TCPS_ESTABLISHED");
return;
case TCPS_CLOSE_WAIT:
db_printf("TCPS_CLOSE_WAIT");
return;
case TCPS_FIN_WAIT_1:
db_printf("TCPS_FIN_WAIT_1");
return;
case TCPS_CLOSING:
db_printf("TCPS_CLOSING");
return;
case TCPS_LAST_ACK:
db_printf("TCPS_LAST_ACK");
return;
case TCPS_FIN_WAIT_2:
db_printf("TCPS_FIN_WAIT_2");
return;
case TCPS_TIME_WAIT:
db_printf("TCPS_TIME_WAIT");
return;
default:
db_printf("unknown");
return;
}
}
static void
db_print_tflags(u_int t_flags)
{
int comma;
comma = 0;
if (t_flags & TF_ACKNOW) {
db_printf("%sTF_ACKNOW", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_DELACK) {
db_printf("%sTF_DELACK", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_NODELAY) {
db_printf("%sTF_NODELAY", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_NOOPT) {
db_printf("%sTF_NOOPT", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_SENTFIN) {
db_printf("%sTF_SENTFIN", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_REQ_SCALE) {
db_printf("%sTF_REQ_SCALE", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_RCVD_SCALE) {
db_printf("%sTF_RECVD_SCALE", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_REQ_TSTMP) {
db_printf("%sTF_REQ_TSTMP", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_RCVD_TSTMP) {
db_printf("%sTF_RCVD_TSTMP", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_SACK_PERMIT) {
db_printf("%sTF_SACK_PERMIT", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_NEEDSYN) {
db_printf("%sTF_NEEDSYN", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_NEEDFIN) {
db_printf("%sTF_NEEDFIN", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_NOPUSH) {
db_printf("%sTF_NOPUSH", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_MORETOCOME) {
db_printf("%sTF_MORETOCOME", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_LQ_OVERFLOW) {
db_printf("%sTF_LQ_OVERFLOW", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_LASTIDLE) {
db_printf("%sTF_LASTIDLE", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_RXWIN0SENT) {
db_printf("%sTF_RXWIN0SENT", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_FASTRECOVERY) {
db_printf("%sTF_FASTRECOVERY", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_CONGRECOVERY) {
db_printf("%sTF_CONGRECOVERY", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_WASFRECOVERY) {
db_printf("%sTF_WASFRECOVERY", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_SIGNATURE) {
db_printf("%sTF_SIGNATURE", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_FORCEDATA) {
db_printf("%sTF_FORCEDATA", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_TSO) {
db_printf("%sTF_TSO", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_ECN_PERMIT) {
db_printf("%sTF_ECN_PERMIT", comma ? ", " : "");
comma = 1;
}
if (t_flags & TF_FASTOPEN) {
db_printf("%sTF_FASTOPEN", comma ? ", " : "");
comma = 1;
}
}
static void
db_print_toobflags(char t_oobflags)
{
int comma;
comma = 0;
if (t_oobflags & TCPOOB_HAVEDATA) {
db_printf("%sTCPOOB_HAVEDATA", comma ? ", " : "");
comma = 1;
}
if (t_oobflags & TCPOOB_HADDATA) {
db_printf("%sTCPOOB_HADDATA", comma ? ", " : "");
comma = 1;
}
}
static void
db_print_tcpcb(struct tcpcb *tp, const char *name, int indent)
{
db_print_indent(indent);
db_printf("%s at %p\n", name, tp);
indent += 2;
db_print_indent(indent);
db_printf("t_segq first: %p t_segqlen: %d t_dupacks: %d\n",
TAILQ_FIRST(&tp->t_segq), tp->t_segqlen, tp->t_dupacks);
db_print_indent(indent);
db_printf("tt_rexmt: %p tt_persist: %p tt_keep: %p\n",
&tp->t_timers->tt_rexmt, &tp->t_timers->tt_persist, &tp->t_timers->tt_keep);
db_print_indent(indent);
db_printf("tt_2msl: %p tt_delack: %p t_inpcb: %p\n", &tp->t_timers->tt_2msl,
&tp->t_timers->tt_delack, tp->t_inpcb);
db_print_indent(indent);
db_printf("t_state: %d (", tp->t_state);
db_print_tstate(tp->t_state);
db_printf(")\n");
db_print_indent(indent);
db_printf("t_flags: 0x%x (", tp->t_flags);
db_print_tflags(tp->t_flags);
db_printf(")\n");
db_print_indent(indent);
db_printf("snd_una: 0x%08x snd_max: 0x%08x snd_nxt: x0%08x\n",
tp->snd_una, tp->snd_max, tp->snd_nxt);
db_print_indent(indent);
db_printf("snd_up: 0x%08x snd_wl1: 0x%08x snd_wl2: 0x%08x\n",
tp->snd_up, tp->snd_wl1, tp->snd_wl2);
db_print_indent(indent);
db_printf("iss: 0x%08x irs: 0x%08x rcv_nxt: 0x%08x\n",
tp->iss, tp->irs, tp->rcv_nxt);
db_print_indent(indent);
db_printf("rcv_adv: 0x%08x rcv_wnd: %u rcv_up: 0x%08x\n",
tp->rcv_adv, tp->rcv_wnd, tp->rcv_up);
db_print_indent(indent);
db_printf("snd_wnd: %u snd_cwnd: %u\n",
tp->snd_wnd, tp->snd_cwnd);
db_print_indent(indent);
db_printf("snd_ssthresh: %u snd_recover: "
"0x%08x\n", tp->snd_ssthresh, tp->snd_recover);
db_print_indent(indent);
db_printf("t_rcvtime: %u t_startime: %u\n",
tp->t_rcvtime, tp->t_starttime);
db_print_indent(indent);
db_printf("t_rttime: %u t_rtsq: 0x%08x\n",
tp->t_rtttime, tp->t_rtseq);
db_print_indent(indent);
db_printf("t_rxtcur: %d t_maxseg: %u t_srtt: %d\n",
tp->t_rxtcur, tp->t_maxseg, tp->t_srtt);
db_print_indent(indent);
db_printf("t_rttvar: %d t_rxtshift: %d t_rttmin: %u "
"t_rttbest: %u\n", tp->t_rttvar, tp->t_rxtshift, tp->t_rttmin,
tp->t_rttbest);
db_print_indent(indent);
db_printf("t_rttupdated: %lu max_sndwnd: %u t_softerror: %d\n",
tp->t_rttupdated, tp->max_sndwnd, tp->t_softerror);
db_print_indent(indent);
db_printf("t_oobflags: 0x%x (", tp->t_oobflags);
db_print_toobflags(tp->t_oobflags);
db_printf(") t_iobc: 0x%02x\n", tp->t_iobc);
db_print_indent(indent);
db_printf("snd_scale: %u rcv_scale: %u request_r_scale: %u\n",
tp->snd_scale, tp->rcv_scale, tp->request_r_scale);
db_print_indent(indent);
db_printf("ts_recent: %u ts_recent_age: %u\n",
tp->ts_recent, tp->ts_recent_age);
db_print_indent(indent);
db_printf("ts_offset: %u last_ack_sent: 0x%08x snd_cwnd_prev: "
"%u\n", tp->ts_offset, tp->last_ack_sent, tp->snd_cwnd_prev);
db_print_indent(indent);
db_printf("snd_ssthresh_prev: %u snd_recover_prev: 0x%08x "
"t_badrxtwin: %u\n", tp->snd_ssthresh_prev,
tp->snd_recover_prev, tp->t_badrxtwin);
db_print_indent(indent);
db_printf("snd_numholes: %d snd_holes first: %p\n",
tp->snd_numholes, TAILQ_FIRST(&tp->snd_holes));
db_print_indent(indent);
db_printf("snd_fack: 0x%08x rcv_numsacks: %d sack_newdata: "
"0x%08x\n", tp->snd_fack, tp->rcv_numsacks, tp->sack_newdata);
/* Skip sackblks, sackhint. */
db_print_indent(indent);
db_printf("t_rttlow: %d rfbuf_ts: %u rfbuf_cnt: %d\n",
tp->t_rttlow, tp->rfbuf_ts, tp->rfbuf_cnt);
}
DB_SHOW_COMMAND(tcpcb, db_show_tcpcb)
{
struct tcpcb *tp;
if (!have_addr) {
db_printf("usage: show tcpcb <addr>\n");
return;
}
tp = (struct tcpcb *)addr;
db_print_tcpcb(tp, "tcpcb", 0);
}
#endif