]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/netinet/tcp_usrreq.c
xnu-7195.101.1.tar.gz
[apple/xnu.git] / bsd / netinet / tcp_usrreq.c
index d68e6f45d5b21048fb9a9a2a6b2b91866e5bdf6b..861c9f71da92bd040980b634d88f920f44d446d2 100644 (file)
@@ -1,23 +1,29 @@
 /*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2020 Apple Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /*
  * Copyright (c) 1982, 1986, 1988, 1993
 #include <sys/kernel.h>
 #include <sys/sysctl.h>
 #include <sys/mbuf.h>
-#if INET6
 #include <sys/domain.h>
-#endif /* INET6 */
+#if XNU_TARGET_OS_OSX
+#include <sys/kasl.h>
+#endif /* XNU_TARGET_OS_OSX */
+#include <sys/priv.h>
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/protosw.h>
+#include <sys/syslog.h>
 
 #include <net/if.h>
 #include <net/route.h>
+#include <net/ntstat.h>
+#include <net/content_filter.h>
+#include <net/multi_layer_pkt_log.h>
 
 #include <netinet/in.h>
 #include <netinet/in_systm.h>
-#if INET6
 #include <netinet/ip6.h>
-#endif
 #include <netinet/in_pcb.h>
-#if INET6
 #include <netinet6/in6_pcb.h>
-#endif
 #include <netinet/in_var.h>
 #include <netinet/ip_var.h>
-#if INET6
 #include <netinet6/ip6_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/tcpip.h>
+#include <netinet/tcp_cc.h>
+#include <netinet/tcp_log.h>
+#include <mach/sdt.h>
 #if TCPDEBUG
 #include <netinet/tcp_debug.h>
 #endif
+#if MPTCP
+#include <netinet/mptcp_var.h>
+#endif /* MPTCP */
 
 #if IPSEC
 #include <netinet6/ipsec.h>
 #endif /*IPSEC*/
 
+#if FLOW_DIVERT
+#include <netinet/flow_divert.h>
+#endif /* FLOW_DIVERT */
+
+errno_t tcp_fill_info_for_info_tuple(struct info_tuple *, struct tcp_info *);
+
+int tcp_sysctl_info(struct sysctl_oid *, void *, int, struct sysctl_req *);
+static void tcp_connection_fill_info(struct tcpcb *tp,
+    struct tcp_connection_info *tci);
+static int tcp_get_mpkl_send_info(struct mbuf *, struct so_mpkl_send_info *);
+
 /*
  * TCP protocol interface to socket abstraction.
  */
-extern char *tcpstates[];      /* XXX ??? */
-
-static int     tcp_attach __P((struct socket *, struct proc *));
-static int     tcp_connect __P((struct tcpcb *, struct sockaddr *, 
-                                struct proc *));
-#if INET6
-static int     tcp6_connect __P((struct tcpcb *, struct sockaddr *,
-                                struct proc *));
-#endif /* INET6 */
-static struct tcpcb *
-               tcp_disconnect __P((struct tcpcb *));
-static struct tcpcb *
-               tcp_usrclosed __P((struct tcpcb *));
+static int      tcp_attach(struct socket *, struct proc *);
+static int      tcp_connect(struct tcpcb *, struct sockaddr *, struct proc *);
+static int      tcp6_connect(struct tcpcb *, struct sockaddr *, struct proc *);
+static int      tcp6_usr_connect(struct socket *, struct sockaddr *,
+    struct proc *);
+static struct tcpcb *tcp_disconnect(struct tcpcb *);
+static struct tcpcb *tcp_usrclosed(struct tcpcb *);
+extern void tcp_sbrcv_trim(struct tcpcb *tp, struct sockbuf *sb);
 
 #if 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)
+#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)
+#define TCPDEBUG0
+#define TCPDEBUG1()
+#define TCPDEBUG2(req)
 #endif
 
+SYSCTL_PROC(_net_inet_tcp, OID_AUTO, info,
+    CTLFLAG_RW | CTLFLAG_LOCKED | CTLFLAG_ANYBODY | CTLFLAG_KERN,
+    0, 0, tcp_sysctl_info, "S", "TCP info per tuple");
+
 /*
  * TCP attaches to socket via pru_attach(), reserving space,
  * and an internet control block.
+ *
+ * Returns:    0                       Success
+ *             EISCONN
+ *     tcp_attach:ENOBUFS
+ *     tcp_attach:ENOMEM
+ *     tcp_attach:???                  [IPSEC specific]
  */
 static int
-tcp_usr_attach(struct socket *so, int proto, struct proc *p)
+tcp_usr_attach(struct socket *so, __unused int proto, struct proc *p)
 {
-       int s = splnet();
        int error;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp = 0;
@@ -147,15 +174,16 @@ tcp_usr_attach(struct socket *so, int proto, struct proc *p)
        }
 
        error = tcp_attach(so, p);
-       if (error)
+       if (error) {
                goto out;
+       }
 
-       if ((so->so_options & SO_LINGER) && so->so_linger == 0)
-               so->so_linger = TCP_LINGERTIME * hz;
+       if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
+               so->so_linger = (short)(TCP_LINGERTIME * hz);
+       }
        tp = sototcpcb(so);
 out:
        TCPDEBUG2(PRU_ATTACH);
-       splx(s);
        return error;
 }
 
@@ -169,89 +197,133 @@ out:
 static int
 tcp_usr_detach(struct socket *so)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
        TCPDEBUG0;
 
-       if (inp == 0) {
-               splx(s);
-               return EINVAL;  /* XXX */
+       if (inp == 0 || (inp->inp_state == INPCB_STATE_DEAD)) {
+               return EINVAL;  /* XXX */
        }
+       socket_lock_assert_owned(so);
        tp = intotcpcb(inp);
        /* In case we got disconnected from the peer */
-        if (tp == 0) 
-           goto out;
+       if (tp == NULL) {
+               goto out;
+       }
        TCPDEBUG1();
+
+       calculate_tcp_clock();
+
        tp = tcp_disconnect(tp);
 out:
        TCPDEBUG2(PRU_DETACH);
-       splx(s);
        return error;
 }
 
-#define        COMMON_START()  TCPDEBUG0; \
-                       do { \
-                                    if (inp == 0) { \
-                                            splx(s); \
-                                            return EINVAL; \
-                                    } \
-                                    tp = intotcpcb(inp); \
-                                    TCPDEBUG1(); \
-                    } while(0)
-                            
-#define COMMON_END(req)        out: TCPDEBUG2(req); splx(s); return error; goto out
+#if NECP
+#define COMMON_START_ALLOW_FLOW_DIVERT(allow)  TCPDEBUG0;               \
+do {                                                                    \
+       if (inp == NULL || inp->inp_state == INPCB_STATE_DEAD)          \
+               return (EINVAL);                                        \
+       if (!(allow) && necp_socket_should_use_flow_divert(inp))        \
+               return (EPROTOTYPE);                                    \
+       tp = intotcpcb(inp);                                            \
+       TCPDEBUG1();                                                    \
+       calculate_tcp_clock();                                          \
+} while (0)
+#else /* NECP */
+#define COMMON_START_ALLOW_FLOW_DIVERT(allow)  TCPDEBUG0;               \
+do {                                                                    \
+       if (inp == NULL || inp->inp_state == INPCB_STATE_DEAD)          \
+               return (EINVAL);                                        \
+       tp = intotcpcb(inp);                                            \
+       TCPDEBUG1();                                                    \
+       calculate_tcp_clock();                                          \
+} while (0)
+#endif /* !NECP */
+
+#define COMMON_START() COMMON_START_ALLOW_FLOW_DIVERT(false)
+#define COMMON_END(req) out: TCPDEBUG2(req); return error; goto out
 
 
 /*
  * Give the socket an address.
+ *
+ * Returns:    0                       Success
+ *             EINVAL                  Invalid argument [COMMON_START]
+ *             EAFNOSUPPORT            Address family not supported
+ *     in_pcbbind:EADDRNOTAVAIL        Address not available.
+ *     in_pcbbind:EINVAL               Invalid argument
+ *     in_pcbbind:EAFNOSUPPORT         Address family not supported [notdef]
+ *     in_pcbbind:EACCES               Permission denied
+ *     in_pcbbind:EADDRINUSE           Address in use
+ *     in_pcbbind:EAGAIN               Resource unavailable, try again
+ *     in_pcbbind:EPERM                Operation not permitted
  */
 static int
 tcp_usr_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
        struct sockaddr_in *sinp;
 
-       COMMON_START();
+       COMMON_START_ALLOW_FLOW_DIVERT(true);
+
+       if (nam->sa_family != 0 && nam->sa_family != AF_INET) {
+               error = EAFNOSUPPORT;
+               goto out;
+       }
 
        /*
         * Must check for multicast addresses and disallow binding
         * to them.
         */
-       sinp = (struct sockaddr_in *)nam;
+       sinp = (struct sockaddr_in *)(void *)nam;
        if (sinp->sin_family == AF_INET &&
            IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
                error = EAFNOSUPPORT;
                goto out;
        }
        error = in_pcbbind(inp, nam, p);
-       if (error)
+       if (error) {
                goto out;
-       COMMON_END(PRU_BIND);
+       }
 
+#if NECP
+       /* Update NECP client with bind result if not in middle of connect */
+       if ((inp->inp_flags2 & INP2_CONNECT_IN_PROGRESS) &&
+           !uuid_is_null(inp->necp_client_uuid)) {
+               socket_unlock(so, 0);
+               necp_client_assign_from_socket(so->last_pid, inp->necp_client_uuid, inp);
+               socket_lock(so, 0);
+       }
+#endif /* NECP */
+
+       COMMON_END(PRU_BIND);
 }
 
-#if INET6
 static int
 tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
        struct sockaddr_in6 *sin6p;
 
-       COMMON_START();
+       COMMON_START_ALLOW_FLOW_DIVERT(true);
+
+       if (nam->sa_family != 0 && nam->sa_family != AF_INET6) {
+               error = EAFNOSUPPORT;
+               goto out;
+       }
 
        /*
         * Must check for multicast addresses and disallow binding
         * to them.
         */
-       sin6p = (struct sockaddr_in6 *)nam;
+       sin6p = (struct sockaddr_in6 *)(void *)nam;
        if (sin6p->sin6_family == AF_INET6 &&
            IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
                error = EAFNOSUPPORT;
@@ -259,10 +331,10 @@ tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
        }
        inp->inp_vflag &= ~INP_IPV4;
        inp->inp_vflag |= INP_IPV6;
-       if (ip6_mapped_addr_on && (inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
-               if (IN6_IS_ADDR_UNSPECIFIED(&sin6p->sin6_addr))
+       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)) {
+               else if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
                        struct sockaddr_in sin;
 
                        in6_sin6_2_sin(&sin, sin6p);
@@ -273,53 +345,98 @@ tcp6_usr_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
                }
        }
        error = in6_pcbbind(inp, nam, p);
-       if (error)
+       if (error) {
                goto out;
+       }
        COMMON_END(PRU_BIND);
 }
-#endif /* INET6 */
 
 /*
  * Prepare to accept connections.
+ *
+ * Returns:    0                       Success
+ *             EINVAL [COMMON_START]
+ *     in_pcbbind:EADDRNOTAVAIL        Address not available.
+ *     in_pcbbind:EINVAL               Invalid argument
+ *     in_pcbbind:EAFNOSUPPORT         Address family not supported [notdef]
+ *     in_pcbbind:EACCES               Permission denied
+ *     in_pcbbind:EADDRINUSE           Address in use
+ *     in_pcbbind:EAGAIN               Resource unavailable, try again
+ *     in_pcbbind:EPERM                Operation not permitted
  */
 static int
 tcp_usr_listen(struct socket *so, struct proc *p)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
 
-       COMMON_START();
-       if (inp->inp_lport == 0)
-               error = in_pcbbind(inp, (struct sockaddr *)0, p);
-       if (error == 0)
+       COMMON_START_ALLOW_FLOW_DIVERT(true);
+       if (inp->inp_lport == 0) {
+               error = in_pcbbind(inp, NULL, p);
+       }
+       if (error == 0) {
                tp->t_state = TCPS_LISTEN;
+       }
+       TCP_LOG_LISTEN(tp, error);
        COMMON_END(PRU_LISTEN);
 }
 
-#if INET6
 static int
 tcp6_usr_listen(struct socket *so, struct proc *p)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
 
-       COMMON_START();
+       COMMON_START_ALLOW_FLOW_DIVERT(true);
        if (inp->inp_lport == 0) {
                inp->inp_vflag &= ~INP_IPV4;
-               if (ip6_mapped_addr_on &&
-                   (inp->inp_flags & IN6P_IPV6_V6ONLY) == 0)
+               if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0) {
                        inp->inp_vflag |= INP_IPV4;
-               error = in6_pcbbind(inp, (struct sockaddr *)0, p);
+               }
+               error = in6_pcbbind(inp, NULL, p);
        }
-       if (error == 0)
+       if (error == 0) {
                tp->t_state = TCPS_LISTEN;
+       }
+       TCP_LOG_LISTEN(tp, error);
        COMMON_END(PRU_LISTEN);
 }
-#endif /* INET6 */
+
+static int
+tcp_connect_complete(struct socket *so)
+{
+       struct tcpcb *tp = sototcpcb(so);
+       struct inpcb *inp = sotoinpcb(so);
+       int error = 0;
+
+       /* TFO delays the tcp_output until later, when the app calls write() */
+       if (so->so_flags1 & SOF1_PRECONNECT_DATA) {
+               if (!necp_socket_is_allowed_to_send_recv(sotoinpcb(so), NULL, 0, NULL, NULL, NULL, NULL)) {
+                       TCP_LOG_DROP_NECP(NULL, NULL, tp, true);
+                       return EHOSTUNREACH;
+               }
+
+               /* Initialize enough state so that we can actually send data */
+               tcp_mss(tp, -1, IFSCOPE_NONE);
+               tp->snd_wnd = tp->t_maxseg;
+               tp->max_sndwnd = tp->snd_wnd;
+       } else {
+               error = tcp_output(tp);
+       }
+
+#if NECP
+       /* Update NECP client with connected five-tuple */
+       if (error == 0 && !uuid_is_null(inp->necp_client_uuid)) {
+               socket_unlock(so, 0);
+               necp_client_assign_from_socket(so->last_pid, inp->necp_client_uuid, inp);
+               socket_lock(so, 0);
+       }
+#endif /* NECP */
+
+       return error;
+}
 
 /*
  * Initiate connection to peer.
@@ -331,50 +448,233 @@ tcp6_usr_listen(struct socket *so, struct proc *p)
 static int
 tcp_usr_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
        struct sockaddr_in *sinp;
 
-       COMMON_START();
+       TCPDEBUG0;
+       if (inp == NULL) {
+               return EINVAL;
+       } else if (inp->inp_state == INPCB_STATE_DEAD) {
+               if (so->so_error) {
+                       error = so->so_error;
+                       so->so_error = 0;
+                       return error;
+               } else {
+                       return EINVAL;
+               }
+       }
+#if NECP
+#if CONTENT_FILTER
+       error = cfil_sock_attach(so, NULL, nam, CFS_CONNECTION_DIR_OUT);
+       if (error != 0) {
+               return error;
+       }
+#endif /* CONTENT_FILTER */
+#if FLOW_DIVERT
+       if (necp_socket_should_use_flow_divert(inp)) {
+               error = flow_divert_pcb_init(so);
+               if (error == 0) {
+                       error = flow_divert_connect_out(so, nam, p);
+               }
+               return error;
+       }
+#endif /* FLOW_DIVERT */
+#endif /* NECP */
+       tp = intotcpcb(inp);
+       TCPDEBUG1();
+
+       calculate_tcp_clock();
 
+       if (nam->sa_family != 0 && nam->sa_family != AF_INET) {
+               error = EAFNOSUPPORT;
+               goto out;
+       }
        /*
         * Must disallow TCP ``connections'' to multicast addresses.
         */
-       sinp = (struct sockaddr_in *)nam;
+       sinp = (struct sockaddr_in *)(void *)nam;
        if (sinp->sin_family == AF_INET
            && IN_MULTICAST(ntohl(sinp->sin_addr.s_addr))) {
                error = EAFNOSUPPORT;
                goto out;
        }
 
-#ifndef __APPLE__
-       prison_remote_ip(p, 0, &sinp->sin_addr.s_addr);
-#endif
-
-       if ((error = tcp_connect(tp, nam, p)) != 0)
+       if ((error = tcp_connect(tp, nam, p)) != 0) {
+               TCP_LOG_CONNECT(tp, true, error);
                goto out;
-       error = tcp_output(tp);
+       }
+
+       error = tcp_connect_complete(so);
+
+       TCP_LOG_CONNECT(tp, true, error);
+
        COMMON_END(PRU_CONNECT);
 }
 
-#if INET6
+static int
+tcp_usr_connectx_common(struct socket *so, int af,
+    struct sockaddr *src, struct sockaddr *dst,
+    struct proc *p, uint32_t ifscope, sae_associd_t aid, sae_connid_t *pcid,
+    uint32_t flags, void *arg, uint32_t arglen, struct uio *auio,
+    user_ssize_t *bytes_written)
+{
+#pragma unused(aid, flags, arg, arglen)
+       struct inpcb *inp = sotoinpcb(so);
+       int error = 0;
+       user_ssize_t datalen = 0;
+
+       if (inp == NULL) {
+               return EINVAL;
+       }
+
+       VERIFY(dst != NULL);
+
+       ASSERT(!(inp->inp_flags2 & INP2_CONNECT_IN_PROGRESS));
+       inp->inp_flags2 |= INP2_CONNECT_IN_PROGRESS;
+
+#if NECP
+       inp_update_necp_policy(inp, src, dst, ifscope);
+#endif /* NECP */
+
+       if ((so->so_flags1 & SOF1_DATA_IDEMPOTENT) &&
+           (tcp_fastopen & TCP_FASTOPEN_CLIENT)) {
+               sototcpcb(so)->t_flagsext |= TF_FASTOPEN;
+       }
+
+       /* bind socket to the specified interface, if requested */
+       if (ifscope != IFSCOPE_NONE &&
+           (error = inp_bindif(inp, ifscope, NULL)) != 0) {
+               goto done;
+       }
+
+       /* if source address and/or port is specified, bind to it */
+       if (src != NULL) {
+               error = sobindlock(so, src, 0); /* already locked */
+               if (error != 0) {
+                       goto done;
+               }
+       }
+
+       switch (af) {
+       case AF_INET:
+               error = tcp_usr_connect(so, dst, p);
+               break;
+       case AF_INET6:
+               error = tcp6_usr_connect(so, dst, p);
+               break;
+       default:
+               VERIFY(0);
+               /* NOTREACHED */
+       }
+
+       if (error != 0) {
+               goto done;
+       }
+
+       /* if there is data, copy it */
+       if (auio != NULL) {
+               socket_unlock(so, 0);
+
+               VERIFY(bytes_written != NULL);
+
+               datalen = uio_resid(auio);
+               error = so->so_proto->pr_usrreqs->pru_sosend(so, NULL,
+                   (uio_t)auio, NULL, NULL, 0);
+               socket_lock(so, 0);
+
+               if (error == 0 || error == EWOULDBLOCK) {
+                       *bytes_written = datalen - uio_resid(auio);
+               }
+
+               /*
+                * sosend returns EWOULDBLOCK if it's a non-blocking
+                * socket or a timeout occured (this allows to return
+                * the amount of queued data through sendit()).
+                *
+                * However, connectx() returns EINPROGRESS in case of a
+                * blocking socket. So we change the return value here.
+                */
+               if (error == EWOULDBLOCK) {
+                       error = EINPROGRESS;
+               }
+       }
+
+       if (error == 0 && pcid != NULL) {
+               *pcid = 1; /* there is only one connection in regular TCP */
+       }
+done:
+       if (error && error != EINPROGRESS) {
+               so->so_flags1 &= ~SOF1_PRECONNECT_DATA;
+       }
+
+       inp->inp_flags2 &= ~INP2_CONNECT_IN_PROGRESS;
+       return error;
+}
+
+static int
+tcp_usr_connectx(struct socket *so, struct sockaddr *src,
+    struct sockaddr *dst, struct proc *p, uint32_t ifscope,
+    sae_associd_t aid, sae_connid_t *pcid, uint32_t flags, void *arg,
+    uint32_t arglen, struct uio *uio, user_ssize_t *bytes_written)
+{
+       return tcp_usr_connectx_common(so, AF_INET, src, dst, p, ifscope, aid,
+                  pcid, flags, arg, arglen, uio, bytes_written);
+}
+
 static int
 tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
        struct sockaddr_in6 *sin6p;
 
-       COMMON_START();
+       TCPDEBUG0;
+       if (inp == NULL) {
+               return EINVAL;
+       } else if (inp->inp_state == INPCB_STATE_DEAD) {
+               if (so->so_error) {
+                       error = so->so_error;
+                       so->so_error = 0;
+                       return error;
+               } else {
+                       return EINVAL;
+               }
+       }
+#if NECP
+#if CONTENT_FILTER
+       error = cfil_sock_attach(so, NULL, nam, CFS_CONNECTION_DIR_OUT);
+       if (error != 0) {
+               return error;
+       }
+#endif /* CONTENT_FILTER */
+#if FLOW_DIVERT
+       if (necp_socket_should_use_flow_divert(inp)) {
+               error = flow_divert_pcb_init(so);
+               if (error == 0) {
+                       error = flow_divert_connect_out(so, nam, p);
+               }
+               return error;
+       }
+#endif /* FLOW_DIVERT */
+#endif /* NECP */
+
+       tp = intotcpcb(inp);
+       TCPDEBUG1();
+
+       calculate_tcp_clock();
+
+       if (nam->sa_family != 0 && nam->sa_family != AF_INET6) {
+               error = EAFNOSUPPORT;
+               goto out;
+       }
 
        /*
         * Must disallow TCP ``connections'' to multicast addresses.
         */
-       sin6p = (struct sockaddr_in6 *)nam;
+       sin6p = (struct sockaddr_in6 *)(void *)nam;
        if (sin6p->sin6_family == AF_INET6
            && IN6_IS_ADDR_MULTICAST(&sin6p->sin6_addr)) {
                error = EAFNOSUPPORT;
@@ -384,28 +684,52 @@ tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
        if (IN6_IS_ADDR_V4MAPPED(&sin6p->sin6_addr)) {
                struct sockaddr_in sin;
 
-               if (!ip6_mapped_addr_on ||
-                   (inp->inp_flags & IN6P_IPV6_V6ONLY))
-                       return(EINVAL);
+               if ((inp->inp_flags & IN6P_IPV6_V6ONLY) != 0) {
+                       error = EINVAL;
+                       goto out;
+               }
 
                in6_sin6_2_sin(&sin, sin6p);
+               /*
+                * Must disallow TCP ``connections'' to multicast addresses.
+                */
+               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 = tcp_connect(tp, (struct sockaddr *)&sin, p)) != 0)
+               if ((error = tcp_connect(tp, (struct sockaddr *)&sin, p)) != 0) {
+                       TCP_LOG_CONNECT(tp, true, error);
                        goto out;
-               error = tcp_output(tp);
+               }
+
+               error = tcp_connect_complete(so);
                goto out;
        }
        inp->inp_vflag &= ~INP_IPV4;
        inp->inp_vflag |= INP_IPV6;
-       if ((error = tcp6_connect(tp, nam, p)) != 0)
-               goto out;
-       error = tcp_output(tp);
-       if (error)
+       if ((error = tcp6_connect(tp, nam, p)) != 0) {
+               TCP_LOG_CONNECT(tp, true, error);
                goto out;
+       }
+
+       error = tcp_connect_complete(so);
+
+       TCP_LOG_CONNECT(tp, true, error);
+
        COMMON_END(PRU_CONNECT);
 }
-#endif /* INET6 */
+
+static int
+tcp6_usr_connectx(struct socket *so, struct sockaddr*src,
+    struct sockaddr *dst, struct proc *p, uint32_t ifscope,
+    sae_associd_t aid, sae_connid_t *pcid, uint32_t flags, void *arg,
+    uint32_t arglen, struct uio *uio, user_ssize_t *bytes_written)
+{
+       return tcp_usr_connectx_common(so, AF_INET6, src, dst, p, ifscope, aid,
+                  pcid, flags, arg, arglen, uio, bytes_written);
+}
 
 /*
  * Initiate disconnect from peer.
@@ -421,19 +745,34 @@ tcp6_usr_connect(struct socket *so, struct sockaddr *nam, struct proc *p)
 static int
 tcp_usr_disconnect(struct socket *so)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
 
+       socket_lock_assert_owned(so);
        COMMON_START();
-        /* In case we got disconnected from the peer */
-        if (tp == 0)
-            goto out;
+       /* In case we got disconnected from the peer */
+       if (tp == NULL) {
+               goto out;
+       }
        tp = tcp_disconnect(tp);
        COMMON_END(PRU_DISCONNECT);
 }
 
+/*
+ * User-protocol pru_disconnectx callback.
+ */
+static int
+tcp_usr_disconnectx(struct socket *so, sae_associd_t aid, sae_connid_t cid)
+{
+#pragma unused(cid)
+       if (aid != SAE_ASSOCID_ANY && aid != SAE_ASSOCID_ALL) {
+               return EINVAL;
+       }
+
+       return tcp_usr_disconnect(so);
+}
+
 /*
  * Accept a connection.  Essentially all the work is
  * done at higher levels; just return the address
@@ -442,31 +781,40 @@ tcp_usr_disconnect(struct socket *so)
 static int
 tcp_usr_accept(struct socket *so, struct sockaddr **nam)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp = NULL;
        TCPDEBUG0;
 
+       in_getpeeraddr(so, nam);
+
        if (so->so_state & SS_ISDISCONNECTED) {
                error = ECONNABORTED;
                goto out;
        }
-       if (inp == 0) {
-               splx(s);
-               return (EINVAL);
+       if (inp == NULL || inp->inp_state == INPCB_STATE_DEAD) {
+               return EINVAL;
        }
+#if NECP
+       else if (necp_socket_should_use_flow_divert(inp)) {
+               return EPROTOTYPE;
+       }
+
+#endif /* NECP */
+
        tp = intotcpcb(inp);
        TCPDEBUG1();
-       in_setpeeraddr(so, nam);
+
+       TCP_LOG_ACCEPT(tp, 0);
+
+       calculate_tcp_clock();
+
        COMMON_END(PRU_ACCEPT);
 }
 
-#if INET6
 static int
 tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp = NULL;
@@ -476,35 +824,96 @@ tcp6_usr_accept(struct socket *so, struct sockaddr **nam)
                error = ECONNABORTED;
                goto out;
        }
-       if (inp == 0) {
-               splx(s);
-               return (EINVAL);
+       if (inp == NULL || inp->inp_state == INPCB_STATE_DEAD) {
+               return EINVAL;
        }
+#if NECP
+       else if (necp_socket_should_use_flow_divert(inp)) {
+               return EPROTOTYPE;
+       }
+
+#endif /* NECP */
+
        tp = intotcpcb(inp);
        TCPDEBUG1();
+
+       TCP_LOG_ACCEPT(tp, 0);
+
+       calculate_tcp_clock();
+
        in6_mapped_peeraddr(so, nam);
        COMMON_END(PRU_ACCEPT);
 }
-#endif /* INET6 */
+
 /*
  * Mark the connection as being incapable of further output.
+ *
+ * Returns:    0                       Success
+ *             EINVAL [COMMON_START]
+ *     tcp_output:EADDRNOTAVAIL
+ *     tcp_output:ENOBUFS
+ *     tcp_output:EMSGSIZE
+ *     tcp_output:EHOSTUNREACH
+ *     tcp_output:ENETUNREACH
+ *     tcp_output:ENETDOWN
+ *     tcp_output:ENOMEM
+ *     tcp_output:EACCES
+ *     tcp_output:EMSGSIZE
+ *     tcp_output:ENOBUFS
+ *     tcp_output:???                  [ignorable: mostly IPSEC/firewall/DLIL]
  */
 static int
 tcp_usr_shutdown(struct socket *so)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
 
-       COMMON_START();
+       TCPDEBUG0;
+       if (inp == NULL || inp->inp_state == INPCB_STATE_DEAD) {
+               return EINVAL;
+       }
+
        socantsendmore(so);
-        /* In case we got disconnected from the peer */
-        if (tp == 0)
-            goto out;
+
+       /*
+        * In case we got disconnected from the peer, or if this is
+        * a socket that is to be flow-diverted (but not yet).
+        */
+       tp = intotcpcb(inp);
+       TCPDEBUG1();
+
+       if (tp == NULL
+#if NECP
+           || (necp_socket_should_use_flow_divert(inp))
+#endif /* NECP */
+           ) {
+               if (tp != NULL) {
+                       error = EPROTOTYPE;
+               }
+               goto out;
+       }
+
+       calculate_tcp_clock();
+
        tp = tcp_usrclosed(tp);
-       if (tp)
+#if MPTCP
+       /* A reset has been sent but socket exists, do not send FIN */
+       if ((so->so_flags & SOF_MP_SUBFLOW) &&
+           (tp) && (tp->t_mpflags & TMPF_RESET)) {
+               goto out;
+       }
+#endif
+#if CONTENT_FILTER
+       /* Don't send a FIN yet */
+       if (tp && !(so->so_state & SS_ISDISCONNECTED) &&
+           cfil_sock_data_pending(&so->so_snd)) {
+               goto out;
+       }
+#endif /* CONTENT_FILTER */
+       if (tp) {
                error = tcp_output(tp);
+       }
        COMMON_END(PRU_SHUTDOWN);
 }
 
@@ -514,16 +923,34 @@ tcp_usr_shutdown(struct socket *so)
 static int
 tcp_usr_rcvd(struct socket *so, int flags)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
 
        COMMON_START();
-        /* In case we got disconnected from the peer */
-        if (tp == 0)
-            goto out;
-       tcp_output(tp);
+       /* In case we got disconnected from the peer */
+       if (tp == NULL) {
+               goto out;
+       }
+       tcp_sbrcv_trim(tp, &so->so_rcv);
+
+       if (flags & MSG_WAITALL) {
+               tp->t_flags |= TF_ACKNOW;
+       }
+
+       /*
+        * This tcp_output is solely there to trigger window-updates.
+        * However, we really do not want these window-updates while we
+        * are still in SYN_SENT or SYN_RECEIVED.
+        */
+       if (TCPS_HAVEESTABLISHED(tp->t_state)) {
+               tcp_output(tp);
+       }
+
+#if CONTENT_FILTER
+       cfil_sock_buf_update(&so->so_rcv);
+#endif /* CONTENT_FILTER */
+
        COMMON_END(PRU_RCVD);
 }
 
@@ -533,53 +960,122 @@ tcp_usr_rcvd(struct socket *so, int flags)
  * pru_*() routines, the mbuf chains are our responsibility.  We
  * must either enqueue them or free them.  The other pru_* routines
  * generally are caller-frees.
+ *
+ * Returns:    0                       Success
+ *             ECONNRESET
+ *             EINVAL
+ *             ENOBUFS
+ *     tcp_connect:EADDRINUSE          Address in use
+ *     tcp_connect:EADDRNOTAVAIL       Address not available.
+ *     tcp_connect:EINVAL              Invalid argument
+ *     tcp_connect:EAFNOSUPPORT        Address family not supported [notdef]
+ *     tcp_connect:EACCES              Permission denied
+ *     tcp_connect:EAGAIN              Resource unavailable, try again
+ *     tcp_connect:EPERM               Operation not permitted
+ *     tcp_output:EADDRNOTAVAIL
+ *     tcp_output:ENOBUFS
+ *     tcp_output:EMSGSIZE
+ *     tcp_output:EHOSTUNREACH
+ *     tcp_output:ENETUNREACH
+ *     tcp_output:ENETDOWN
+ *     tcp_output:ENOMEM
+ *     tcp_output:EACCES
+ *     tcp_output:EMSGSIZE
+ *     tcp_output:ENOBUFS
+ *     tcp_output:???                  [ignorable: mostly IPSEC/firewall/DLIL]
+ *     tcp6_connect:???                [IPV6 only]
  */
 static int
-tcp_usr_send(struct socket *so, int flags, struct mbuf *m, 
-            struct sockaddr *nam, struct mbuf *control, struct proc *p)
+tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
+    struct sockaddr *nam, struct mbuf *control, struct proc *p)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
-#if INET6
+       uint32_t mpkl_len = 0; /* length of mbuf chain */
+       uint32_t mpkl_seq; /* sequence number where new data is added */
+       struct so_mpkl_send_info mpkl_send_info = {};
+
        int isipv6;
-#endif
        TCPDEBUG0;
 
-       if (inp == NULL) {
+       if (inp == NULL || inp->inp_state == INPCB_STATE_DEAD
+#if NECP
+           || (necp_socket_should_use_flow_divert(inp))
+#endif /* NECP */
+           ) {
                /*
                 * OOPS! we lost a race, the TCP session got reset after
                 * we checked SS_CANTSENDMORE, eg: while doing uiomove or a
                 * network interrupt in the non-splnet() section of sosend().
                 */
-               if (m)
+               if (m != NULL) {
                        m_freem(m);
-               if (control)
+               }
+               if (control != NULL) {
                        m_freem(control);
-               error = ECONNRESET;     /* XXX EPIPE? */
+                       control = NULL;
+               }
+
+               if (inp == NULL) {
+                       error = ECONNRESET;     /* XXX EPIPE? */
+               } else {
+                       error = EPROTOTYPE;
+               }
                tp = NULL;
                TCPDEBUG1();
                goto out;
        }
-#if INET6
        isipv6 = nam && nam->sa_family == AF_INET6;
-#endif /* INET6 */
        tp = intotcpcb(inp);
        TCPDEBUG1();
-       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;
+
+       calculate_tcp_clock();
+
+       if (net_mpklog_enabled) {
+               mpkl_seq = tp->snd_una + so->so_snd.sb_cc;
+               if (m) {
+                       mpkl_len = m_length(m);
                }
-               m_freem(control);       /* empty control, just free it */
+               if (so->so_flags1 & SOF1_MPKL_SEND_INFO) {
+                       uuid_copy(mpkl_send_info.mpkl_uuid, so->so_mpkl_send_uuid);
+                       mpkl_send_info.mpkl_proto = so->so_mpkl_send_proto;
+               }
+       }
+
+       if (control != NULL) {
+               if (control->m_len > 0 && net_mpklog_enabled) {
+                       error = tcp_get_mpkl_send_info(control, &mpkl_send_info);
+                       /*
+                        * Intepretation of the returned code:
+                        *  0: client wants us to use value passed in SCM_MPKL_SEND_INFO
+                        *  1: SCM_MPKL_SEND_INFO was not present
+                        *  other: failure
+                        */
+                       if (error != 0 && error != ENOMSG) {
+                               m_freem(control);
+                               if (m != NULL) {
+                                       m_freem(m);
+                               }
+                               control = NULL;
+                               m = NULL;
+                               goto out;
+                       }
+               }
+               /*
+                * Silently drop unsupported ancillary data messages
+                */
+               m_freem(control);
+               control = NULL;
        }
-       if(!(flags & PRUS_OOB)) {
-               sbappend(&so->so_snd, m);
+
+       /* MPTCP sublow socket buffers must not be compressed */
+       VERIFY(!(so->so_flags & SOF_MP_SUBFLOW) ||
+           (so->so_snd.sb_flags & SB_NOCOMPRESS));
+
+       if (!(flags & PRUS_OOB) || (so->so_flags1 & SOF1_PRECONNECT_DATA)) {
+               sbappendstream(&so->so_snd, m);
+
                if (nam && tp->t_state < TCPS_SYN_SENT) {
                        /*
                         * Do implied connect if not yet connected,
@@ -587,17 +1083,24 @@ tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
                         * initialize maxseg/maxopd using peer's cached
                         * MSS.
                         */
-#if INET6
-                       if (isipv6)
+                       if (isipv6) {
                                error = tcp6_connect(tp, nam, p);
-                       else
-#endif /* INET6 */
-                       error = tcp_connect(tp, nam, p);
-                       if (error)
+                       } else {
+                               error = tcp_connect(tp, nam, p);
+                       }
+                       if (error) {
+                               TCP_LOG_CONNECT(tp, true, error);
                                goto out;
+                       }
                        tp->snd_wnd = TTCP_CLIENT_SND_WND;
-                       tcp_mss(tp, -1);
-               }
+                       tp->max_sndwnd = tp->snd_wnd;
+                       tcp_mss(tp, -1, IFSCOPE_NONE);
+
+                       TCP_LOG_CONNECT(tp, true, error);
+
+                       /* The sequence number of the data is past the SYN */
+                       mpkl_seq = tp->iss + 1;
+               }
 
                if (flags & PRUS_EOF) {
                        /*
@@ -608,14 +1111,18 @@ tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
                        tp = tcp_usrclosed(tp);
                }
                if (tp != NULL) {
-                       if (flags & PRUS_MORETOCOME)
+                       if (flags & PRUS_MORETOCOME) {
                                tp->t_flags |= TF_MORETOCOME;
+                       }
                        error = tcp_output(tp);
-                       if (flags & PRUS_MORETOCOME)
+                       if (flags & PRUS_MORETOCOME) {
                                tp->t_flags &= ~TF_MORETOCOME;
+                       }
                }
        } else {
-               if (sbspace(&so->so_snd) < -512) {
+               if (sbspace(&so->so_snd) == 0) {
+                       /* if no space is left in sockbuf,
+                        * do not try to squeeze in OOB traffic */
                        m_freem(m);
                        error = ENOBUFS;
                        goto out;
@@ -628,7 +1135,7 @@ tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
                 * of data past the urgent section.
                 * Otherwise, snd_up should be one lower.
                 */
-               sbappend(&so->so_snd, m);
+               sbappendstream(&so->so_snd, m);
                if (nam && tp->t_state < TCPS_SYN_SENT) {
                        /*
                         * Do implied connect if not yet connected,
@@ -636,24 +1143,53 @@ tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
                         * initialize maxseg/maxopd using peer's cached
                         * MSS.
                         */
-#if INET6
-                       if (isipv6)
+                       if (isipv6) {
                                error = tcp6_connect(tp, nam, p);
-                       else
-#endif /* INET6 */
-                       error = tcp_connect(tp, nam, p);
-                       if (error)
+                       } else {
+                               error = tcp_connect(tp, nam, p);
+                       }
+                       if (error) {
+                               TCP_LOG_CONNECT(tp, true, error);
                                goto out;
+                       }
                        tp->snd_wnd = TTCP_CLIENT_SND_WND;
-                       tcp_mss(tp, -1);
+                       tp->max_sndwnd = tp->snd_wnd;
+                       tcp_mss(tp, -1, IFSCOPE_NONE);
+
+                       TCP_LOG_CONNECT(tp, true, error);
                }
                tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
-               tp->t_force = 1;
+               tp->t_flagsext |= TF_FORCE;
                error = tcp_output(tp);
-               tp->t_force = 0;
+               tp->t_flagsext &= ~TF_FORCE;
        }
-       COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB : 
-                  ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
+
+       if (net_mpklog_enabled && (inp = tp->t_inpcb) != NULL &&
+           ((inp->inp_last_outifp != NULL &&
+           (inp->inp_last_outifp->if_xflags & IFXF_MPK_LOG)) ||
+           (inp->inp_boundifp != NULL &&
+           (inp->inp_boundifp->if_xflags & IFXF_MPK_LOG)))) {
+               MPKL_TCP_SEND(tcp_mpkl_log_object,
+                   mpkl_send_info.mpkl_proto, mpkl_send_info.mpkl_uuid,
+                   ntohs(inp->inp_lport), ntohs(inp->inp_fport),
+                   mpkl_seq, mpkl_len,
+                   so->last_pid, so->so_log_seqn++);
+       }
+
+       /*
+        * We wait for the socket to successfully connect before returning.
+        * This allows us to signal a timeout to the application.
+        */
+       if (so->so_state & SS_ISCONNECTING) {
+               if (so->so_state & SS_NBIO) {
+                       error = EWOULDBLOCK;
+               } else {
+                       error = sbwait(&so->so_snd);
+               }
+       }
+
+       COMMON_END((flags & PRUS_OOB) ? PRU_SENDOOB :
+           ((flags & PRUS_EOF) ? PRU_SEND_EOF : PRU_SEND));
 }
 
 /*
@@ -662,33 +1198,39 @@ tcp_usr_send(struct socket *so, int flags, struct mbuf *m,
 static int
 tcp_usr_abort(struct socket *so)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
 
        COMMON_START();
-        /* In case we got disconnected from the peer */
-        if (tp == 0)
-            goto out;
+       /* In case we got disconnected from the peer */
+       if (tp == NULL) {
+               goto out;
+       }
        tp = tcp_drop(tp, ECONNABORTED);
+       VERIFY(so->so_usecount > 0);
+       so->so_usecount--;
        COMMON_END(PRU_ABORT);
 }
 
 /*
  * Receive out-of-band data.
+ *
+ * Returns:    0                       Success
+ *             EINVAL [COMMON_START]
+ *             EINVAL
+ *             EWOULDBLOCK
  */
 static int
 tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
 {
-       int s = splnet();
        int error = 0;
        struct inpcb *inp = sotoinpcb(so);
        struct tcpcb *tp;
 
        COMMON_START();
        if ((so->so_oobmark == 0 &&
-            (so->so_state & SS_RCVATMARK) == 0) ||
+           (so->so_state & SS_RCVATMARK) == 0) ||
            so->so_options & SO_OOBINLINE ||
            tp->t_oobflags & TCPOOB_HADDATA) {
                error = EINVAL;
@@ -700,29 +1242,82 @@ tcp_usr_rcvoob(struct socket *so, struct mbuf *m, int flags)
        }
        m->m_len = 1;
        *mtod(m, caddr_t) = tp->t_iobc;
-       if ((flags & MSG_PEEK) == 0)
+       so->so_state &= ~SS_RCVATMARK;
+       if ((flags & MSG_PEEK) == 0) {
                tp->t_oobflags ^= (TCPOOB_HAVEDATA | TCPOOB_HADDATA);
+       }
        COMMON_END(PRU_RCVOOB);
 }
 
+static int
+tcp_usr_preconnect(struct socket *so)
+{
+       struct inpcb *inp = sotoinpcb(so);
+       int error = 0;
+
+#if NECP
+       if (necp_socket_should_use_flow_divert(inp)) {
+               /* May happen, if in tcp_usr_connect we did not had a chance
+                * to set the usrreqs (due to some error). So, let's get out
+                * of here.
+                */
+               goto out;
+       }
+#endif /* NECP */
+
+       error = tcp_output(sototcpcb(so));
+
+       soclearfastopen(so);
+
+       COMMON_END(PRU_PRECONNECT);
+}
+
 /* xxx - should be const */
 struct pr_usrreqs tcp_usrreqs = {
-       tcp_usr_abort, tcp_usr_accept, tcp_usr_attach, tcp_usr_bind,
-       tcp_usr_connect, pru_connect2_notsupp, in_control, tcp_usr_detach,
-       tcp_usr_disconnect, tcp_usr_listen, in_setpeeraddr, tcp_usr_rcvd,
-       tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown,
-       in_setsockaddr, sosend, soreceive, sopoll
+       .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_connectx =         tcp_usr_connectx,
+       .pru_control =          in_control,
+       .pru_detach =           tcp_usr_detach,
+       .pru_disconnect =       tcp_usr_disconnect,
+       .pru_disconnectx =      tcp_usr_disconnectx,
+       .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_shutdown =         tcp_usr_shutdown,
+       .pru_sockaddr =         in_getsockaddr,
+       .pru_sosend =           sosend,
+       .pru_soreceive =        soreceive,
+       .pru_preconnect =       tcp_usr_preconnect,
 };
 
-#if INET6
 struct pr_usrreqs tcp6_usrreqs = {
-       tcp_usr_abort, tcp6_usr_accept, tcp_usr_attach, tcp6_usr_bind,
-       tcp6_usr_connect, pru_connect2_notsupp, in6_control, tcp_usr_detach,
-       tcp_usr_disconnect, tcp6_usr_listen, in6_mapped_peeraddr, tcp_usr_rcvd,
-       tcp_usr_rcvoob, tcp_usr_send, pru_sense_null, tcp_usr_shutdown,
-       in6_mapped_sockaddr, sosend, soreceive, sopoll
+       .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_connectx =         tcp6_usr_connectx,
+       .pru_control =          in6_control,
+       .pru_detach =           tcp_usr_detach,
+       .pru_disconnect =       tcp_usr_disconnect,
+       .pru_disconnectx =      tcp_usr_disconnectx,
+       .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_shutdown =         tcp_usr_shutdown,
+       .pru_sockaddr =         in6_mapped_sockaddr,
+       .pru_sosend =           sosend,
+       .pru_soreceive =        soreceive,
+       .pru_preconnect =       tcp_usr_preconnect,
 };
-#endif /* INET6 */
 
 /*
  * Common subroutine to open a TCP connection to remote host specified
@@ -733,26 +1328,37 @@ struct pr_usrreqs tcp6_usrreqs = {
  * 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.
+ *
+ * Returns:    0                       Success
+ *             EADDRINUSE
+ *             EINVAL
+ *     in_pcbbind:EADDRNOTAVAIL        Address not available.
+ *     in_pcbbind:EINVAL               Invalid argument
+ *     in_pcbbind:EAFNOSUPPORT         Address family not supported [notdef]
+ *     in_pcbbind:EACCES               Permission denied
+ *     in_pcbbind:EADDRINUSE           Address in use
+ *     in_pcbbind:EAGAIN               Resource unavailable, try again
+ *     in_pcbbind:EPERM                Operation not permitted
+ *     in_pcbladdr:EINVAL              Invalid argument
+ *     in_pcbladdr:EAFNOSUPPORT        Address family not supported
+ *     in_pcbladdr:EADDRNOTAVAIL       Address not available
  */
 static int
-tcp_connect(tp, nam, p)
-       register struct tcpcb *tp;
-       struct sockaddr *nam;
-       struct proc *p;
+tcp_connect(struct tcpcb *tp, struct sockaddr *nam, struct proc *p)
 {
        struct inpcb *inp = tp->t_inpcb, *oinp;
        struct socket *so = inp->inp_socket;
        struct tcpcb *otp;
-       struct sockaddr_in *sin = (struct sockaddr_in *)nam;
-       struct sockaddr_in *ifaddr;
-       struct rmxp_tao *taop;
-       struct rmxp_tao tao_noncached;
-       int error;
+       struct sockaddr_in *sin = (struct sockaddr_in *)(void *)nam;
+       struct in_addr laddr;
+       int error = 0;
+       struct ifnet *outif = NULL;
 
        if (inp->inp_lport == 0) {
-               error = in_pcbbind(inp, (struct sockaddr *)0, p);
-               if (error)
-                       return error;
+               error = in_pcbbind(inp, NULL, p);
+               if (error) {
+                       goto done;
+               }
        }
 
        /*
@@ -760,152 +1366,653 @@ tcp_connect(tp, nam, p)
         * earlier incarnation of this same connection still in
         * TIME_WAIT state, creating an ADDRINUSE error.
         */
-       error = in_pcbladdr(inp, nam, &ifaddr);
-       if (error)
-               return error;
+       error = in_pcbladdr(inp, nam, &laddr, IFSCOPE_NONE, &outif, 0);
+       if (error) {
+               goto done;
+       }
+
+       socket_unlock(inp->inp_socket, 0);
        oinp = in_pcblookup_hash(inp->inp_pcbinfo,
            sin->sin_addr, sin->sin_port,
-           inp->inp_laddr.s_addr != INADDR_ANY ? inp->inp_laddr
-                                               : ifaddr->sin_addr,
-           inp->inp_lport,  0, NULL);
+           inp->inp_laddr.s_addr != INADDR_ANY ? inp->inp_laddr : laddr,
+           inp->inp_lport, 0, NULL);
+
+       socket_lock(inp->inp_socket, 0);
        if (oinp) {
+               if (oinp != inp) { /* 4143933: avoid deadlock if inp == oinp */
+                       socket_lock(oinp->inp_socket, 1);
+               }
+               if (in_pcb_checkstate(oinp, WNT_RELEASE, 1) == WNT_STOPUSING) {
+                       if (oinp != inp) {
+                               socket_unlock(oinp->inp_socket, 1);
+                       }
+                       goto skip_oinp;
+               }
+
                if (oinp != inp && (otp = intotcpcb(oinp)) != NULL &&
-               otp->t_state == TCPS_TIME_WAIT &&
-                   otp->t_starttime < tcp_msl &&
-                   (otp->t_flags & TF_RCVD_CC))
+                   otp->t_state == TCPS_TIME_WAIT &&
+                   ((int)(tcp_now - otp->t_starttime)) < tcp_msl &&
+                   (otp->t_flags & TF_RCVD_CC)) {
                        otp = tcp_close(otp);
-               else
-                       return EADDRINUSE;
+               } else {
+                       printf("tcp_connect: inp=0x%llx err=EADDRINUSE\n",
+                           (uint64_t)VM_KERNEL_ADDRPERM(inp));
+                       if (oinp != inp) {
+                               socket_unlock(oinp->inp_socket, 1);
+                       }
+                       error = EADDRINUSE;
+                       goto done;
+               }
+               if (oinp != inp) {
+                       socket_unlock(oinp->inp_socket, 1);
+               }
+       }
+skip_oinp:
+       if ((inp->inp_laddr.s_addr == INADDR_ANY ? laddr.s_addr :
+           inp->inp_laddr.s_addr) == sin->sin_addr.s_addr &&
+           inp->inp_lport == sin->sin_port) {
+               error = EINVAL;
+               goto done;
+       }
+       if (!lck_rw_try_lock_exclusive(inp->inp_pcbinfo->ipi_lock)) {
+               /*lock inversion issue, mostly with udp multicast packets */
+               socket_unlock(inp->inp_socket, 0);
+               lck_rw_lock_exclusive(inp->inp_pcbinfo->ipi_lock);
+               socket_lock(inp->inp_socket, 0);
+       }
+       if (inp->inp_laddr.s_addr == INADDR_ANY) {
+               inp->inp_laddr = laddr;
+               /* no reference needed */
+               inp->inp_last_outifp = outif;
+
+               inp->inp_flags |= INP_INADDR_ANY;
        }
-       if ((inp->inp_laddr.s_addr == INADDR_ANY ? ifaddr->sin_addr.s_addr :
-                inp->inp_laddr.s_addr) == sin->sin_addr.s_addr &&
-           inp->inp_lport == sin->sin_port)
-                       return EINVAL;
-       if (inp->inp_laddr.s_addr == INADDR_ANY)
-               inp->inp_laddr = ifaddr->sin_addr;
        inp->inp_faddr = sin->sin_addr;
        inp->inp_fport = sin->sin_port;
        in_pcbrehash(inp);
+       lck_rw_done(inp->inp_pcbinfo->ipi_lock);
+
+       if (inp->inp_flowhash == 0) {
+               inp->inp_flowhash = inp_calc_flowhash(inp);
+       }
 
-       /* Compute window scaling to request.  */
-       while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
-           (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
-               tp->request_r_scale++;
+       tcp_set_max_rwinscale(tp, so);
 
        soisconnecting(so);
        tcpstat.tcps_connattempt++;
        tp->t_state = TCPS_SYN_SENT;
-       tp->t_timer[TCPT_KEEP] = tcp_keepinit;
+       tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, TCP_CONN_KEEPINIT(tp));
        tp->iss = tcp_new_isn(tp);
        tcp_sendseqinit(tp);
-
-       /*
-        * Generate a CC value for this connection and
-        * check whether CC or CCnew should be used.
-        */
-       if ((taop = tcp_gettaocache(tp->t_inpcb)) == NULL) {
-               taop = &tao_noncached;
-               bzero(taop, sizeof(*taop));
+       tp->t_connect_time = tcp_now;
+       if (nstat_collect) {
+               nstat_route_connect_attempt(inp->inp_route.ro_rt);
        }
 
-       tp->cc_send = CC_INC(tcp_ccgen);
-       if (taop->tao_ccsent != 0 &&
-           CC_GEQ(tp->cc_send, taop->tao_ccsent)) {
-               taop->tao_ccsent = tp->cc_send;
-       } else {
-               taop->tao_ccsent = 0;
-               tp->t_flags |= TF_SENDCCNEW;
+       tcp_add_fsw_flow(tp, outif);
+
+done:
+       if (outif != NULL) {
+               ifnet_release(outif);
        }
 
-       return 0;
+       return error;
 }
 
-#if INET6
 static int
-tcp6_connect(tp, nam, p)
-       register struct tcpcb *tp;
-       struct sockaddr *nam;
-       struct proc *p;
+tcp6_connect(struct tcpcb *tp, struct sockaddr *nam, struct proc *p)
 {
        struct inpcb *inp = tp->t_inpcb, *oinp;
        struct socket *so = inp->inp_socket;
        struct tcpcb *otp;
-       struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
-       struct in6_addr *addr6;
-       struct rmxp_tao *taop;
-       struct rmxp_tao tao_noncached;
-       int error;
+       struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)(void *)nam;
+       struct in6_addr addr6;
+       int error = 0;
+       struct ifnet *outif = NULL;
 
        if (inp->inp_lport == 0) {
-               error = in6_pcbbind(inp, (struct sockaddr *)0, p);
-               if (error)
-                       return error;
+               error = in6_pcbbind(inp, NULL, p);
+               if (error) {
+                       goto done;
+               }
        }
 
        /*
         * 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.
+        *
+        * in6_pcbladdr() might return an ifp with its reference held
+        * even in the error case, so make sure that it's released
+        * whenever it's non-NULL.
         */
-       error = in6_pcbladdr(inp, nam, &addr6);
-       if (error)
-               return error;
+       error = in6_pcbladdr(inp, nam, &addr6, &outif);
+       if (error) {
+               goto done;
+       }
+       socket_unlock(inp->inp_socket, 0);
        oinp = in6_pcblookup_hash(inp->inp_pcbinfo,
-                                 &sin6->sin6_addr, sin6->sin6_port,
-                                 IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
-                                 ? addr6
-                                 : &inp->in6p_laddr,
-                                 inp->inp_lport,  0, NULL);
+           &sin6->sin6_addr, sin6->sin6_port,
+           IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
+           ? &addr6
+           : &inp->in6p_laddr,
+           inp->inp_lport, 0, NULL);
+       socket_lock(inp->inp_socket, 0);
        if (oinp) {
                if (oinp != inp && (otp = intotcpcb(oinp)) != NULL &&
                    otp->t_state == TCPS_TIME_WAIT &&
-                   otp->t_starttime < tcp_msl &&
-                   (otp->t_flags & TF_RCVD_CC))
+                   ((int)(tcp_now - otp->t_starttime)) < tcp_msl &&
+                   (otp->t_flags & TF_RCVD_CC)) {
                        otp = tcp_close(otp);
-               else
-                       return EADDRINUSE;
+               } else {
+                       error = EADDRINUSE;
+                       goto done;
+               }
+       }
+       if (!lck_rw_try_lock_exclusive(inp->inp_pcbinfo->ipi_lock)) {
+               /*lock inversion issue, mostly with udp multicast packets */
+               socket_unlock(inp->inp_socket, 0);
+               lck_rw_lock_exclusive(inp->inp_pcbinfo->ipi_lock);
+               socket_lock(inp->inp_socket, 0);
+       }
+       if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
+               inp->in6p_laddr = addr6;
+               inp->in6p_last_outifp = outif;  /* no reference needed */
+               inp->in6p_flags |= INP_IN6ADDR_ANY;
        }
-       if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
-               inp->in6p_laddr = *addr6;
        inp->in6p_faddr = sin6->sin6_addr;
        inp->inp_fport = sin6->sin6_port;
-       if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != NULL)
-               inp->in6p_flowinfo = sin6->sin6_flowinfo;
+       if ((sin6->sin6_flowinfo & IPV6_FLOWINFO_MASK) != 0) {
+               inp->inp_flow = sin6->sin6_flowinfo;
+       }
        in_pcbrehash(inp);
+       lck_rw_done(inp->inp_pcbinfo->ipi_lock);
 
-       /* Compute window scaling to request.  */
-       while (tp->request_r_scale < TCP_MAX_WINSHIFT &&
-           (TCP_MAXWIN << tp->request_r_scale) < so->so_rcv.sb_hiwat)
-               tp->request_r_scale++;
+       if (inp->inp_flowhash == 0) {
+               inp->inp_flowhash = inp_calc_flowhash(inp);
+       }
+       /* update flowinfo - RFC 6437 */
+       if (inp->inp_flow == 0 && inp->in6p_flags & IN6P_AUTOFLOWLABEL) {
+               inp->inp_flow &= ~IPV6_FLOWLABEL_MASK;
+               inp->inp_flow |=
+                   (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK);
+       }
+
+       tcp_set_max_rwinscale(tp, so);
 
        soisconnecting(so);
        tcpstat.tcps_connattempt++;
        tp->t_state = TCPS_SYN_SENT;
-       tp->t_timer[TCPT_KEEP] = tcp_keepinit;
+       tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp,
+           TCP_CONN_KEEPINIT(tp));
        tp->iss = tcp_new_isn(tp);
        tcp_sendseqinit(tp);
+       tp->t_connect_time = tcp_now;
+       if (nstat_collect) {
+               nstat_route_connect_attempt(inp->inp_route.ro_rt);
+       }
 
-       /*
-        * Generate a CC value for this connection and
-        * check whether CC or CCnew should be used.
-        */
-       if ((taop = tcp_gettaocache(tp->t_inpcb)) == NULL) {
-               taop = &tao_noncached;
-               bzero(taop, sizeof(*taop));
+       tcp_add_fsw_flow(tp, outif);
+
+done:
+       if (outif != NULL) {
+               ifnet_release(outif);
+       }
+
+       return error;
+}
+
+/*
+ * Export TCP internal state information via a struct tcp_info
+ */
+void
+tcp_fill_info(struct tcpcb *tp, struct tcp_info *ti)
+{
+       struct inpcb *inp = tp->t_inpcb;
+
+       bzero(ti, sizeof(*ti));
+
+       ti->tcpi_state = (uint8_t)tp->t_state;
+       ti->tcpi_flowhash = inp->inp_flowhash;
+
+       if (tp->t_state > TCPS_LISTEN) {
+               if (TSTMP_SUPPORTED(tp)) {
+                       ti->tcpi_options |= TCPI_OPT_TIMESTAMPS;
+               }
+               if (SACK_ENABLED(tp)) {
+                       ti->tcpi_options |= TCPI_OPT_SACK;
+               }
+               if (TCP_WINDOW_SCALE_ENABLED(tp)) {
+                       ti->tcpi_options |= TCPI_OPT_WSCALE;
+                       ti->tcpi_snd_wscale = tp->snd_scale;
+                       ti->tcpi_rcv_wscale = tp->rcv_scale;
+               }
+               if (TCP_ECN_ENABLED(tp)) {
+                       ti->tcpi_options |= TCPI_OPT_ECN;
+               }
+
+               /* Are we in retranmission episode */
+               if (IN_FASTRECOVERY(tp) || tp->t_rxtshift > 0) {
+                       ti->tcpi_flags |= TCPI_FLAG_LOSSRECOVERY;
+               }
+
+               if (tp->t_flags & TF_STREAMING_ON) {
+                       ti->tcpi_flags |= TCPI_FLAG_STREAMING_ON;
+               }
+
+               ti->tcpi_rto = tp->t_timer[TCPT_REXMT] ? tp->t_rxtcur : 0;
+               ti->tcpi_snd_mss = tp->t_maxseg;
+               ti->tcpi_rcv_mss = tp->t_maxseg;
+
+               ti->tcpi_rttcur = tp->t_rttcur;
+               ti->tcpi_srtt = tp->t_srtt >> TCP_RTT_SHIFT;
+               ti->tcpi_rttvar = tp->t_rttvar >> TCP_RTTVAR_SHIFT;
+               ti->tcpi_rttbest = tp->t_rttbest >> TCP_RTT_SHIFT;
+
+               ti->tcpi_snd_ssthresh = tp->snd_ssthresh;
+               ti->tcpi_snd_cwnd = tp->snd_cwnd;
+               ti->tcpi_snd_sbbytes = inp->inp_socket->so_snd.sb_cc;
+
+               ti->tcpi_rcv_space = tp->rcv_wnd;
+
+               ti->tcpi_snd_wnd = tp->snd_wnd;
+               ti->tcpi_snd_nxt = tp->snd_nxt;
+               ti->tcpi_rcv_nxt = tp->rcv_nxt;
+
+               /* convert bytes/msec to bits/sec */
+               if ((tp->t_flagsext & TF_MEASURESNDBW) != 0 &&
+                   tp->t_bwmeas != NULL) {
+                       ti->tcpi_snd_bw = (tp->t_bwmeas->bw_sndbw * 8000);
+               }
+
+               ti->tcpi_last_outif = (tp->t_inpcb->inp_last_outifp == NULL) ? 0 :
+                   tp->t_inpcb->inp_last_outifp->if_index;
+
+               //atomic_get_64(ti->tcpi_txbytes, &inp->inp_stat->txbytes);
+               ti->tcpi_txpackets = inp->inp_stat->txpackets;
+               ti->tcpi_txbytes = inp->inp_stat->txbytes;
+               ti->tcpi_txretransmitbytes = tp->t_stat.txretransmitbytes;
+               ti->tcpi_txretransmitpackets = tp->t_stat.rxmitpkts;
+               ti->tcpi_txunacked = tp->snd_max - tp->snd_una;
+
+               //atomic_get_64(ti->tcpi_rxbytes, &inp->inp_stat->rxbytes);
+               ti->tcpi_rxpackets = inp->inp_stat->rxpackets;
+               ti->tcpi_rxbytes = inp->inp_stat->rxbytes;
+               ti->tcpi_rxduplicatebytes = tp->t_stat.rxduplicatebytes;
+               ti->tcpi_rxoutoforderbytes = tp->t_stat.rxoutoforderbytes;
+
+               if (tp->t_state > TCPS_LISTEN) {
+                       ti->tcpi_synrexmits = (uint8_t)tp->t_stat.rxmitsyns;
+               }
+               ti->tcpi_cell_rxpackets = inp->inp_cstat->rxpackets;
+               ti->tcpi_cell_rxbytes = inp->inp_cstat->rxbytes;
+               ti->tcpi_cell_txpackets = inp->inp_cstat->txpackets;
+               ti->tcpi_cell_txbytes = inp->inp_cstat->txbytes;
+
+               ti->tcpi_wifi_rxpackets = inp->inp_wstat->rxpackets;
+               ti->tcpi_wifi_rxbytes = inp->inp_wstat->rxbytes;
+               ti->tcpi_wifi_txpackets = inp->inp_wstat->txpackets;
+               ti->tcpi_wifi_txbytes = inp->inp_wstat->txbytes;
+
+               ti->tcpi_wired_rxpackets = inp->inp_Wstat->rxpackets;
+               ti->tcpi_wired_rxbytes = inp->inp_Wstat->rxbytes;
+               ti->tcpi_wired_txpackets = inp->inp_Wstat->txpackets;
+               ti->tcpi_wired_txbytes = inp->inp_Wstat->txbytes;
+               tcp_get_connectivity_status(tp, &ti->tcpi_connstatus);
+
+               ti->tcpi_tfo_syn_data_rcv = !!(tp->t_tfo_stats & TFO_S_SYNDATA_RCV);
+               ti->tcpi_tfo_cookie_req_rcv = !!(tp->t_tfo_stats & TFO_S_COOKIEREQ_RECV);
+               ti->tcpi_tfo_cookie_sent = !!(tp->t_tfo_stats & TFO_S_COOKIE_SENT);
+               ti->tcpi_tfo_cookie_invalid = !!(tp->t_tfo_stats & TFO_S_COOKIE_INVALID);
+
+               ti->tcpi_tfo_cookie_req = !!(tp->t_tfo_stats & TFO_S_COOKIE_REQ);
+               ti->tcpi_tfo_cookie_rcv = !!(tp->t_tfo_stats & TFO_S_COOKIE_RCV);
+               ti->tcpi_tfo_syn_data_sent = !!(tp->t_tfo_stats & TFO_S_SYN_DATA_SENT);
+               ti->tcpi_tfo_syn_data_acked = !!(tp->t_tfo_stats & TFO_S_SYN_DATA_ACKED);
+               ti->tcpi_tfo_syn_loss = !!(tp->t_tfo_stats & TFO_S_SYN_LOSS);
+               ti->tcpi_tfo_cookie_wrong = !!(tp->t_tfo_stats & TFO_S_COOKIE_WRONG);
+               ti->tcpi_tfo_no_cookie_rcv = !!(tp->t_tfo_stats & TFO_S_NO_COOKIE_RCV);
+               ti->tcpi_tfo_heuristics_disable = !!(tp->t_tfo_stats & TFO_S_HEURISTICS_DISABLE);
+               ti->tcpi_tfo_send_blackhole = !!(tp->t_tfo_stats & TFO_S_SEND_BLACKHOLE);
+               ti->tcpi_tfo_recv_blackhole = !!(tp->t_tfo_stats & TFO_S_RECV_BLACKHOLE);
+               ti->tcpi_tfo_onebyte_proxy = !!(tp->t_tfo_stats & TFO_S_ONE_BYTE_PROXY);
+
+               ti->tcpi_ecn_client_setup = !!(tp->ecn_flags & TE_SETUPSENT);
+               ti->tcpi_ecn_server_setup = !!(tp->ecn_flags & TE_SETUPRECEIVED);
+               ti->tcpi_ecn_success = (tp->ecn_flags & TE_ECN_ON) == TE_ECN_ON ? 1 : 0;
+               ti->tcpi_ecn_lost_syn = !!(tp->ecn_flags & TE_LOST_SYN);
+               ti->tcpi_ecn_lost_synack = !!(tp->ecn_flags & TE_LOST_SYNACK);
+
+               ti->tcpi_local_peer = !!(tp->t_flags & TF_LOCAL);
+
+               if (tp->t_inpcb->inp_last_outifp != NULL) {
+                       if (IFNET_IS_CELLULAR(tp->t_inpcb->inp_last_outifp)) {
+                               ti->tcpi_if_cell = 1;
+                       }
+                       if (IFNET_IS_WIFI(tp->t_inpcb->inp_last_outifp)) {
+                               ti->tcpi_if_wifi = 1;
+                       }
+                       if (IFNET_IS_WIRED(tp->t_inpcb->inp_last_outifp)) {
+                               ti->tcpi_if_wired = 1;
+                       }
+                       if (IFNET_IS_WIFI_INFRA(tp->t_inpcb->inp_last_outifp)) {
+                               ti->tcpi_if_wifi_infra = 1;
+                       }
+                       if (tp->t_inpcb->inp_last_outifp->if_eflags & IFEF_AWDL) {
+                               ti->tcpi_if_wifi_awdl = 1;
+                       }
+               }
+               if (tp->tcp_cc_index == TCP_CC_ALGO_BACKGROUND_INDEX) {
+                       ti->tcpi_snd_background = 1;
+               }
+               if (tcp_recv_bg == 1 ||
+                   IS_TCP_RECV_BG(tp->t_inpcb->inp_socket)) {
+                       ti->tcpi_rcv_background = 1;
+               }
+
+               ti->tcpi_ecn_recv_ce = tp->t_ecn_recv_ce;
+               ti->tcpi_ecn_recv_cwr = tp->t_ecn_recv_cwr;
+
+               ti->tcpi_rcvoopack = tp->t_rcvoopack;
+               ti->tcpi_pawsdrop = tp->t_pawsdrop;
+               ti->tcpi_sack_recovery_episode = tp->t_sack_recovery_episode;
+               ti->tcpi_reordered_pkts = tp->t_reordered_pkts;
+               ti->tcpi_dsack_sent = tp->t_dsack_sent;
+               ti->tcpi_dsack_recvd = tp->t_dsack_recvd;
+       }
+}
+
+__private_extern__ errno_t
+tcp_fill_info_for_info_tuple(struct info_tuple *itpl, struct tcp_info *ti)
+{
+       struct inpcbinfo *pcbinfo = NULL;
+       struct inpcb *inp = NULL;
+       struct socket *so;
+       struct tcpcb *tp;
+
+       if (itpl->itpl_proto == IPPROTO_TCP) {
+               pcbinfo = &tcbinfo;
+       } else {
+               return EINVAL;
        }
 
-       tp->cc_send = CC_INC(tcp_ccgen);
-       if (taop->tao_ccsent != 0 &&
-           CC_GEQ(tp->cc_send, taop->tao_ccsent)) {
-               taop->tao_ccsent = tp->cc_send;
+       if (itpl->itpl_local_sa.sa_family == AF_INET &&
+           itpl->itpl_remote_sa.sa_family == AF_INET) {
+               inp = in_pcblookup_hash(pcbinfo,
+                   itpl->itpl_remote_sin.sin_addr,
+                   itpl->itpl_remote_sin.sin_port,
+                   itpl->itpl_local_sin.sin_addr,
+                   itpl->itpl_local_sin.sin_port,
+                   0, NULL);
+       } else if (itpl->itpl_local_sa.sa_family == AF_INET6 &&
+           itpl->itpl_remote_sa.sa_family == AF_INET6) {
+               struct in6_addr ina6_local;
+               struct in6_addr ina6_remote;
+
+               ina6_local = itpl->itpl_local_sin6.sin6_addr;
+               if (IN6_IS_SCOPE_LINKLOCAL(&ina6_local) &&
+                   itpl->itpl_local_sin6.sin6_scope_id) {
+                       ina6_local.s6_addr16[1] = htons((uint16_t)itpl->itpl_local_sin6.sin6_scope_id);
+               }
+
+               ina6_remote = itpl->itpl_remote_sin6.sin6_addr;
+               if (IN6_IS_SCOPE_LINKLOCAL(&ina6_remote) &&
+                   itpl->itpl_remote_sin6.sin6_scope_id) {
+                       ina6_remote.s6_addr16[1] = htons((uint16_t)itpl->itpl_remote_sin6.sin6_scope_id);
+               }
+
+               inp = in6_pcblookup_hash(pcbinfo,
+                   &ina6_remote,
+                   itpl->itpl_remote_sin6.sin6_port,
+                   &ina6_local,
+                   itpl->itpl_local_sin6.sin6_port,
+                   0, NULL);
        } else {
-               taop->tao_ccsent = 0;
-               tp->t_flags |= TF_SENDCCNEW;
+               return EINVAL;
+       }
+       if (inp == NULL || (so = inp->inp_socket) == NULL) {
+               return ENOENT;
+       }
+
+       socket_lock(so, 0);
+       if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) {
+               socket_unlock(so, 0);
+               return ENOENT;
+       }
+       tp = intotcpcb(inp);
+
+       tcp_fill_info(tp, ti);
+       socket_unlock(so, 0);
+
+       return 0;
+}
+
+static void
+tcp_connection_fill_info(struct tcpcb *tp, struct tcp_connection_info *tci)
+{
+       struct inpcb *inp = tp->t_inpcb;
+
+       bzero(tci, sizeof(*tci));
+       tci->tcpi_state = (uint8_t)tp->t_state;
+       if (tp->t_state > TCPS_LISTEN) {
+               if (TSTMP_SUPPORTED(tp)) {
+                       tci->tcpi_options |= TCPCI_OPT_TIMESTAMPS;
+               }
+               if (SACK_ENABLED(tp)) {
+                       tci->tcpi_options |= TCPCI_OPT_SACK;
+               }
+               if (TCP_WINDOW_SCALE_ENABLED(tp)) {
+                       tci->tcpi_options |= TCPCI_OPT_WSCALE;
+                       tci->tcpi_snd_wscale = tp->snd_scale;
+                       tci->tcpi_rcv_wscale = tp->rcv_scale;
+               }
+               if (TCP_ECN_ENABLED(tp)) {
+                       tci->tcpi_options |= TCPCI_OPT_ECN;
+               }
+               if (IN_FASTRECOVERY(tp) || tp->t_rxtshift > 0) {
+                       tci->tcpi_flags |= TCPCI_FLAG_LOSSRECOVERY;
+               }
+               if (tp->t_flagsext & TF_PKTS_REORDERED) {
+                       tci->tcpi_flags |= TCPCI_FLAG_REORDERING_DETECTED;
+               }
+               tci->tcpi_rto = (tp->t_timer[TCPT_REXMT] > 0) ?
+                   tp->t_rxtcur : 0;
+               tci->tcpi_maxseg = tp->t_maxseg;
+               tci->tcpi_snd_ssthresh = tp->snd_ssthresh;
+               tci->tcpi_snd_cwnd = tp->snd_cwnd;
+               tci->tcpi_snd_wnd = tp->snd_wnd;
+               tci->tcpi_snd_sbbytes = inp->inp_socket->so_snd.sb_cc;
+               tci->tcpi_rcv_wnd = tp->rcv_wnd;
+               tci->tcpi_rttcur = tp->t_rttcur;
+               tci->tcpi_srtt = (tp->t_srtt >> TCP_RTT_SHIFT);
+               tci->tcpi_rttvar = (tp->t_rttvar >> TCP_RTTVAR_SHIFT);
+               tci->tcpi_txpackets = inp->inp_stat->txpackets;
+               tci->tcpi_txbytes = inp->inp_stat->txbytes;
+               tci->tcpi_txretransmitbytes = tp->t_stat.txretransmitbytes;
+               tci->tcpi_txretransmitpackets = tp->t_stat.rxmitpkts;
+               tci->tcpi_rxpackets = inp->inp_stat->rxpackets;
+               tci->tcpi_rxbytes = inp->inp_stat->rxbytes;
+               tci->tcpi_rxoutoforderbytes = tp->t_stat.rxoutoforderbytes;
+
+               tci->tcpi_tfo_syn_data_rcv = !!(tp->t_tfo_stats & TFO_S_SYNDATA_RCV);
+               tci->tcpi_tfo_cookie_req_rcv = !!(tp->t_tfo_stats & TFO_S_COOKIEREQ_RECV);
+               tci->tcpi_tfo_cookie_sent = !!(tp->t_tfo_stats & TFO_S_COOKIE_SENT);
+               tci->tcpi_tfo_cookie_invalid = !!(tp->t_tfo_stats & TFO_S_COOKIE_INVALID);
+               tci->tcpi_tfo_cookie_req = !!(tp->t_tfo_stats & TFO_S_COOKIE_REQ);
+               tci->tcpi_tfo_cookie_rcv = !!(tp->t_tfo_stats & TFO_S_COOKIE_RCV);
+               tci->tcpi_tfo_syn_data_sent = !!(tp->t_tfo_stats & TFO_S_SYN_DATA_SENT);
+               tci->tcpi_tfo_syn_data_acked = !!(tp->t_tfo_stats & TFO_S_SYN_DATA_ACKED);
+               tci->tcpi_tfo_syn_loss = !!(tp->t_tfo_stats & TFO_S_SYN_LOSS);
+               tci->tcpi_tfo_cookie_wrong = !!(tp->t_tfo_stats & TFO_S_COOKIE_WRONG);
+               tci->tcpi_tfo_no_cookie_rcv = !!(tp->t_tfo_stats & TFO_S_NO_COOKIE_RCV);
+               tci->tcpi_tfo_heuristics_disable = !!(tp->t_tfo_stats & TFO_S_HEURISTICS_DISABLE);
+               tci->tcpi_tfo_send_blackhole = !!(tp->t_tfo_stats & TFO_S_SEND_BLACKHOLE);
+               tci->tcpi_tfo_recv_blackhole = !!(tp->t_tfo_stats & TFO_S_RECV_BLACKHOLE);
+               tci->tcpi_tfo_onebyte_proxy = !!(tp->t_tfo_stats & TFO_S_ONE_BYTE_PROXY);
+       }
+}
+
+
+__private_extern__ int
+tcp_sysctl_info(__unused struct sysctl_oid *oidp, __unused void *arg1, __unused int arg2, struct sysctl_req *req)
+{
+       int error;
+       struct tcp_info ti = {};
+       struct info_tuple itpl;
+
+       if (req->newptr == USER_ADDR_NULL) {
+               return EINVAL;
+       }
+       if (req->newlen < sizeof(struct info_tuple)) {
+               return EINVAL;
+       }
+       error = SYSCTL_IN(req, &itpl, sizeof(struct info_tuple));
+       if (error != 0) {
+               return error;
+       }
+       error = tcp_fill_info_for_info_tuple(&itpl, &ti);
+       if (error != 0) {
+               return error;
+       }
+       error = SYSCTL_OUT(req, &ti, sizeof(struct tcp_info));
+       if (error != 0) {
+               return error;
        }
 
        return 0;
 }
-#endif /* INET6 */
+
+static int
+tcp_lookup_peer_pid_locked(struct socket *so, pid_t *out_pid)
+{
+       int error = EHOSTUNREACH;
+       *out_pid = -1;
+       if ((so->so_state & SS_ISCONNECTED) == 0) {
+               return ENOTCONN;
+       }
+
+       struct inpcb    *inp = (struct inpcb*)so->so_pcb;
+       uint16_t                lport = inp->inp_lport;
+       uint16_t                fport = inp->inp_fport;
+       struct inpcb    *finp = NULL;
+       struct  in6_addr laddr6, faddr6;
+       struct in_addr laddr4, faddr4;
+
+       if (inp->inp_vflag & INP_IPV6) {
+               laddr6 = inp->in6p_laddr;
+               faddr6 = inp->in6p_faddr;
+       } else if (inp->inp_vflag & INP_IPV4) {
+               laddr4 = inp->inp_laddr;
+               faddr4 = inp->inp_faddr;
+       }
+
+       socket_unlock(so, 0);
+       if (inp->inp_vflag & INP_IPV6) {
+               finp = in6_pcblookup_hash(&tcbinfo, &laddr6, lport, &faddr6, fport, 0, NULL);
+       } else if (inp->inp_vflag & INP_IPV4) {
+               finp = in_pcblookup_hash(&tcbinfo, laddr4, lport, faddr4, fport, 0, NULL);
+       }
+
+       if (finp) {
+               *out_pid = finp->inp_socket->last_pid;
+               error = 0;
+               in_pcb_checkstate(finp, WNT_RELEASE, 0);
+       }
+       socket_lock(so, 0);
+
+       return error;
+}
+
+void
+tcp_getconninfo(struct socket *so, struct conninfo_tcp *tcp_ci)
+{
+       (void) tcp_lookup_peer_pid_locked(so, &tcp_ci->tcpci_peer_pid);
+       tcp_fill_info(sototcpcb(so), &tcp_ci->tcpci_tcp_info);
+}
+
+void
+tcp_clear_keep_alive_offload(struct socket *so)
+{
+       struct inpcb *inp;
+       struct ifnet *ifp;
+
+       inp = sotoinpcb(so);
+       if (inp == NULL) {
+               return;
+       }
+
+       if ((inp->inp_flags2 & INP2_KEEPALIVE_OFFLOAD) == 0) {
+               return;
+       }
+
+       ifp = inp->inp_boundifp != NULL ? inp->inp_boundifp :
+           inp->inp_last_outifp;
+       if (ifp == NULL) {
+               panic("%s: so %p inp %p ifp NULL",
+                   __func__, so, inp);
+       }
+
+       ifnet_lock_exclusive(ifp);
+
+       if (ifp->if_tcp_kao_cnt == 0) {
+               panic("%s: so %p inp %p ifp %p if_tcp_kao_cnt == 0",
+                   __func__, so, inp, ifp);
+       }
+       ifp->if_tcp_kao_cnt--;
+       inp->inp_flags2 &= ~INP2_KEEPALIVE_OFFLOAD;
+
+       ifnet_lock_done(ifp);
+}
+
+static int
+tcp_set_keep_alive_offload(struct socket *so, struct proc *proc)
+{
+       int error = 0;
+       struct inpcb *inp;
+       struct ifnet *ifp;
+
+       inp = sotoinpcb(so);
+       if (inp == NULL) {
+               return ECONNRESET;
+       }
+       if ((inp->inp_flags2 & INP2_KEEPALIVE_OFFLOAD) != 0) {
+               return 0;
+       }
+
+       ifp = inp->inp_boundifp != NULL ? inp->inp_boundifp :
+           inp->inp_last_outifp;
+       if (ifp == NULL) {
+               error = ENXIO;
+               os_log_info(OS_LOG_DEFAULT,
+                   "%s: error %d for proc %s[%u] out ifp is not set\n",
+                   __func__, error,
+                   proc != NULL ? proc->p_comm : "kernel",
+                   proc != NULL ? proc->p_pid : 0);
+               return ENXIO;
+       }
+
+       error = if_get_tcp_kao_max(ifp);
+       if (error != 0) {
+               return error;
+       }
+
+       ifnet_lock_exclusive(ifp);
+       if (ifp->if_tcp_kao_cnt < ifp->if_tcp_kao_max) {
+               ifp->if_tcp_kao_cnt++;
+               inp->inp_flags2 |= INP2_KEEPALIVE_OFFLOAD;
+       } else {
+               error = ETOOMANYREFS;
+               os_log_info(OS_LOG_DEFAULT,
+                   "%s: error %d for proc %s[%u] if_tcp_kao_max %u\n",
+                   __func__, error,
+                   proc != NULL ? proc->p_comm : "kernel",
+                   proc != NULL ? proc->p_pid : 0,
+                   ifp->if_tcp_kao_max);
+       }
+       ifnet_lock_done(ifp);
+
+       return error;
+}
 
 /*
  * The new sockopt interface makes it possible for us to block in the
@@ -915,36 +2022,33 @@ tcp6_connect(tp, nam, p)
  * splnet() any more.  This needs more examination.)
  */
 int
-tcp_ctloutput(so, sopt)
-       struct socket *so;
-       struct sockopt *sopt;
+tcp_ctloutput(struct socket *so, struct sockopt *sopt)
 {
-       int     error, opt, optval, s;
-       struct  inpcb *inp;
-       struct  tcpcb *tp;
+       int     error = 0, opt = 0, optval = 0;
+       struct  inpcb *inp;
+       struct  tcpcb *tp;
 
-       error = 0;
-       s = splnet();           /* XXX */
        inp = sotoinpcb(so);
        if (inp == NULL) {
-               splx(s);
-               return (ECONNRESET);
+               return ECONNRESET;
        }
-       if (sopt->sopt_level != IPPROTO_TCP) {
-#if INET6
-               if (INP_CHECK_SOCKAF(so, AF_INET6))
+       /* Allow <SOL_SOCKET,SO_FLUSH/SO_TRAFFIC_MGT_BACKGROUND> at this level */
+       if (sopt->sopt_level != IPPROTO_TCP &&
+           !(sopt->sopt_level == SOL_SOCKET && (sopt->sopt_name == SO_FLUSH ||
+           sopt->sopt_name == SO_TRAFFIC_MGT_BACKGROUND))) {
+               if (SOCK_CHECK_DOM(so, PF_INET6)) {
                        error = ip6_ctloutput(so, sopt);
-               else
-#endif /* INET6 */
-               error = ip_ctloutput(so, sopt);
-               splx(s);
-               return (error);
+               } else {
+                       error = ip_ctloutput(so, sopt);
+               }
+               return error;
        }
        tp = intotcpcb(inp);
-        if (tp == NULL) {
-                splx(s);
-                return (ECONNRESET);
-        }
+       if (tp == NULL) {
+               return ECONNRESET;
+       }
+
+       calculate_tcp_clock();
 
        switch (sopt->sopt_dir) {
        case SOPT_SET:
@@ -953,9 +2057,10 @@ tcp_ctloutput(so, sopt)
                case TCP_NOOPT:
                case TCP_NOPUSH:
                        error = sooptcopyin(sopt, &optval, sizeof optval,
-                                           sizeof optval);
-                       if (error)
+                           sizeof optval);
+                       if (error) {
                                break;
+                       }
 
                        switch (sopt->sopt_name) {
                        case TCP_NODELAY:
@@ -972,24 +2077,462 @@ tcp_ctloutput(so, sopt)
                                break;
                        }
 
-                       if (optval)
+                       if (optval) {
                                tp->t_flags |= opt;
-                       else
+                       } else {
                                tp->t_flags &= ~opt;
+                       }
                        break;
-
+               case TCP_RXT_FINDROP:
+               case TCP_NOTIMEWAIT:
+                       error = sooptcopyin(sopt, &optval, sizeof optval,
+                           sizeof optval);
+                       if (error) {
+                               break;
+                       }
+                       switch (sopt->sopt_name) {
+                       case TCP_RXT_FINDROP:
+                               opt = TF_RXTFINDROP;
+                               break;
+                       case TCP_NOTIMEWAIT:
+                               opt = TF_NOTIMEWAIT;
+                               break;
+                       default:
+                               opt = 0;
+                               break;
+                       }
+                       if (optval) {
+                               tp->t_flagsext |= opt;
+                       } else {
+                               tp->t_flagsext &= ~opt;
+                       }
+                       break;
+               case TCP_MEASURE_SND_BW:
+                       error = sooptcopyin(sopt, &optval, sizeof optval,
+                           sizeof optval);
+                       if (error) {
+                               break;
+                       }
+                       opt = TF_MEASURESNDBW;
+                       if (optval) {
+                               if (tp->t_bwmeas == NULL) {
+                                       tp->t_bwmeas = tcp_bwmeas_alloc(tp);
+                                       if (tp->t_bwmeas == NULL) {
+                                               error = ENOMEM;
+                                               break;
+                                       }
+                               }
+                               tp->t_flagsext |= opt;
+                       } else {
+                               tp->t_flagsext &= ~opt;
+                               /* Reset snd bw measurement state */
+                               tp->t_flagsext &= ~(TF_BWMEAS_INPROGRESS);
+                               if (tp->t_bwmeas != NULL) {
+                                       tcp_bwmeas_free(tp);
+                               }
+                       }
+                       break;
+               case TCP_MEASURE_BW_BURST: {
+                       struct tcp_measure_bw_burst in;
+                       uint32_t minpkts, maxpkts;
+                       bzero(&in, sizeof(in));
+
+                       error = sooptcopyin(sopt, &in, sizeof(in),
+                           sizeof(in));
+                       if (error) {
+                               break;
+                       }
+                       if ((tp->t_flagsext & TF_MEASURESNDBW) == 0 ||
+                           tp->t_bwmeas == NULL) {
+                               error = EINVAL;
+                               break;
+                       }
+                       minpkts = (in.min_burst_size != 0) ? in.min_burst_size :
+                           tp->t_bwmeas->bw_minsizepkts;
+                       maxpkts = (in.max_burst_size != 0) ? in.max_burst_size :
+                           tp->t_bwmeas->bw_maxsizepkts;
+                       if (minpkts > maxpkts) {
+                               error = EINVAL;
+                               break;
+                       }
+                       tp->t_bwmeas->bw_minsizepkts = minpkts;
+                       tp->t_bwmeas->bw_maxsizepkts = maxpkts;
+                       tp->t_bwmeas->bw_minsize = (minpkts * tp->t_maxseg);
+                       tp->t_bwmeas->bw_maxsize = (maxpkts * tp->t_maxseg);
+                       break;
+               }
                case TCP_MAXSEG:
                        error = sooptcopyin(sopt, &optval, sizeof optval,
-                                           sizeof optval);
-                       if (error)
+                           sizeof optval);
+                       if (error) {
                                break;
+                       }
 
-                       if (optval > 0 && optval <= tp->t_maxseg)
+                       if (optval > 0 && optval <= tp->t_maxseg &&
+                           optval + 40 >= tcp_minmss) {
                                tp->t_maxseg = optval;
-                       else
+                       } else {
                                error = EINVAL;
+                       }
+                       break;
+
+               case TCP_KEEPALIVE:
+                       error = sooptcopyin(sopt, &optval, sizeof optval,
+                           sizeof optval);
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > UINT32_MAX / TCP_RETRANSHZ) {
+                               error = EINVAL;
+                       } else {
+                               tp->t_keepidle = optval * TCP_RETRANSHZ;
+                               /* reset the timer to new value */
+                               tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp,
+                                   TCP_CONN_KEEPIDLE(tp));
+                               tcp_check_timer_state(tp);
+                       }
+                       break;
+
+               case TCP_CONNECTIONTIMEOUT:
+                       error = sooptcopyin(sopt, &optval, sizeof optval,
+                           sizeof optval);
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > UINT32_MAX / TCP_RETRANSHZ) {
+                               error = EINVAL;
+                       } else {
+                               tp->t_keepinit = optval * TCP_RETRANSHZ;
+                               if (tp->t_state == TCPS_SYN_RECEIVED ||
+                                   tp->t_state == TCPS_SYN_SENT) {
+                                       tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp,
+                                           TCP_CONN_KEEPINIT(tp));
+                                       tcp_check_timer_state(tp);
+                               }
+                       }
+                       break;
+
+               case TCP_KEEPINTVL:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > UINT32_MAX / TCP_RETRANSHZ) {
+                               error = EINVAL;
+                       } else {
+                               tp->t_keepintvl = optval * TCP_RETRANSHZ;
+                               if (tp->t_state == TCPS_FIN_WAIT_2 &&
+                                   TCP_CONN_MAXIDLE(tp) > 0) {
+                                       tp->t_timer[TCPT_2MSL] = OFFSET_FROM_START(tp,
+                                           TCP_CONN_MAXIDLE(tp));
+                                       tcp_check_timer_state(tp);
+                               }
+                       }
+                       break;
+
+               case TCP_KEEPCNT:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > INT32_MAX) {
+                               error = EINVAL;
+                       } else {
+                               tp->t_keepcnt = optval;
+                               if (tp->t_state == TCPS_FIN_WAIT_2 &&
+                                   TCP_CONN_MAXIDLE(tp) > 0) {
+                                       tp->t_timer[TCPT_2MSL] = OFFSET_FROM_START(tp,
+                                           TCP_CONN_MAXIDLE(tp));
+                                       tcp_check_timer_state(tp);
+                               }
+                       }
+                       break;
+
+               case TCP_KEEPALIVE_OFFLOAD:
+                       if ((error = priv_check_cred(kauth_cred_get(),
+                           PRIV_NETINET_TCP_KA_OFFLOAD, 0)) != 0) {
+                               break;
+                       }
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > INT32_MAX) {
+                               error = EINVAL;
+                               break;
+                       }
+                       if (optval != 0) {
+                               error = tcp_set_keep_alive_offload(so,
+                                   sopt->sopt_p);
+                       } else {
+                               tcp_clear_keep_alive_offload(so);
+                       }
+                       break;
+
+               case PERSIST_TIMEOUT:
+                       error = sooptcopyin(sopt, &optval, sizeof optval,
+                           sizeof optval);
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0) {
+                               error = EINVAL;
+                       } else {
+                               tp->t_persist_timeout = optval * TCP_RETRANSHZ;
+                       }
+                       break;
+               case TCP_RXT_CONNDROPTIME:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0) {
+                               error = EINVAL;
+                       } else {
+                               tp->t_rxt_conndroptime = optval * TCP_RETRANSHZ;
+                       }
+                       break;
+               case TCP_NOTSENT_LOWAT:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0) {
+                               error = EINVAL;
+                               break;
+                       } else {
+                               if (optval == 0) {
+                                       so->so_flags &= ~(SOF_NOTSENT_LOWAT);
+                                       tp->t_notsent_lowat = 0;
+                               } else {
+                                       so->so_flags |= SOF_NOTSENT_LOWAT;
+                                       tp->t_notsent_lowat = optval;
+                               }
+                       }
+                       break;
+               case TCP_ADAPTIVE_READ_TIMEOUT:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 ||
+                           optval > TCP_ADAPTIVE_TIMEOUT_MAX) {
+                               error = EINVAL;
+                               break;
+                       } else if (optval == 0) {
+                               tp->t_adaptive_rtimo = 0;
+                               tcp_keepalive_reset(tp);
+
+                               if (tp->t_mpsub) {
+                                       mptcp_reset_keepalive(tp);
+                               }
+                       } else {
+                               tp->t_adaptive_rtimo = (uint8_t)optval;
+                       }
+                       break;
+               case TCP_ADAPTIVE_WRITE_TIMEOUT:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 ||
+                           optval > TCP_ADAPTIVE_TIMEOUT_MAX) {
+                               error = EINVAL;
+                               break;
+                       } else {
+                               tp->t_adaptive_wtimo = (uint8_t)optval;
+                       }
+                       break;
+               case TCP_SENDMOREACKS:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > 1) {
+                               error = EINVAL;
+                       } else if (optval == 0) {
+                               tp->t_flagsext &= ~(TF_NOSTRETCHACK);
+                       } else {
+                               tp->t_flagsext |= TF_NOSTRETCHACK;
+                       }
+                       break;
+               case TCP_DISABLE_BLACKHOLE_DETECTION:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > 1) {
+                               error = EINVAL;
+                       } else if (optval == 0) {
+                               tp->t_flagsext &= ~TF_NOBLACKHOLE_DETECTION;
+                       } else {
+                               tp->t_flagsext |= TF_NOBLACKHOLE_DETECTION;
+                               if ((tp->t_flags & TF_BLACKHOLE) &&
+                                   tp->t_pmtud_saved_maxopd > 0) {
+                                       tcp_pmtud_revert_segment_size(tp);
+                               }
+                       }
+                       break;
+               case TCP_FASTOPEN:
+                       if (!(tcp_fastopen & TCP_FASTOPEN_SERVER)) {
+                               error = ENOTSUP;
+                               break;
+                       }
+
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > 1) {
+                               error = EINVAL;
+                               break;
+                       }
+                       if (tp->t_state != TCPS_LISTEN) {
+                               error =  EINVAL;
+                               break;
+                       }
+                       if (optval) {
+                               tp->t_flagsext |= TF_FASTOPEN;
+                       } else {
+                               tcp_disable_tfo(tp);
+                       }
+                       break;
+               case TCP_FASTOPEN_FORCE_HEURISTICS:
+
+                       break;
+               case TCP_FASTOPEN_FORCE_ENABLE:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0 || optval > 1) {
+                               error = EINVAL;
+                               break;
+                       }
+
+                       if (tp->t_state != TCPS_CLOSED) {
+                               error =  EINVAL;
+                               break;
+                       }
+                       if (optval) {
+                               tp->t_flagsext |= TF_FASTOPEN_FORCE_ENABLE;
+                       } else {
+                               tp->t_flagsext &= ~TF_FASTOPEN_FORCE_ENABLE;
+                       }
+
+                       break;
+               case TCP_ENABLE_ECN:
+                       error = sooptcopyin(sopt, &optval, sizeof optval,
+                           sizeof optval);
+                       if (error) {
+                               break;
+                       }
+                       if (optval) {
+                               tp->ecn_flags |= TE_ECN_MODE_ENABLE;
+                               tp->ecn_flags &= ~TE_ECN_MODE_DISABLE;
+                       } else {
+                               tp->ecn_flags &= ~TE_ECN_MODE_ENABLE;
+                               tp->ecn_flags |= TE_ECN_MODE_DISABLE;
+                       }
                        break;
+               case TCP_ECN_MODE:
+                       error = sooptcopyin(sopt, &optval, sizeof optval,
+                           sizeof optval);
+                       if (error) {
+                               break;
+                       }
+                       if (optval == ECN_MODE_DEFAULT) {
+                               tp->ecn_flags &= ~TE_ECN_MODE_ENABLE;
+                               tp->ecn_flags &= ~TE_ECN_MODE_DISABLE;
+                       } else if (optval == ECN_MODE_ENABLE) {
+                               tp->ecn_flags |= TE_ECN_MODE_ENABLE;
+                               tp->ecn_flags &= ~TE_ECN_MODE_DISABLE;
+                       } else if (optval == ECN_MODE_DISABLE) {
+                               tp->ecn_flags &= ~TE_ECN_MODE_ENABLE;
+                               tp->ecn_flags |= TE_ECN_MODE_DISABLE;
+                       } else {
+                               error = EINVAL;
+                       }
+                       break;
+               case TCP_NOTIFY_ACKNOWLEDGEMENT:
+                       error = sooptcopyin(sopt, &optval,
+                           sizeof(optval), sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval <= 0) {
+                               error = EINVAL;
+                               break;
+                       }
+                       if (tp->t_notify_ack_count >= TCP_MAX_NOTIFY_ACK) {
+                               error = ETOOMANYREFS;
+                               break;
+                       }
+
+                       /*
+                        * validate that the given marker id is not
+                        * a duplicate to avoid ambiguity
+                        */
+                       if ((error = tcp_notify_ack_id_valid(tp, so,
+                           optval)) != 0) {
+                               break;
+                       }
+                       error = tcp_add_notify_ack_marker(tp, optval);
+                       break;
+               case SO_FLUSH:
+                       if ((error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval))) != 0) {
+                               break;
+                       }
+
+                       error = inp_flush(inp, optval);
+                       break;
+
+               case SO_TRAFFIC_MGT_BACKGROUND:
+                       if ((error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval))) != 0) {
+                               break;
+                       }
 
+                       if (optval) {
+                               socket_set_traffic_mgt_flags_locked(so,
+                                   TRAFFIC_MGT_SO_BACKGROUND);
+                       } else {
+                               socket_clear_traffic_mgt_flags_locked(so,
+                                   TRAFFIC_MGT_SO_BACKGROUND);
+                       }
+                       break;
+               case TCP_RXT_MINIMUM_TIMEOUT:
+                       error = sooptcopyin(sopt, &optval, sizeof(optval),
+                           sizeof(optval));
+                       if (error) {
+                               break;
+                       }
+                       if (optval < 0) {
+                               error = EINVAL;
+                               break;
+                       }
+                       if (optval == 0) {
+                               tp->t_rxt_minimum_timeout = 0;
+                       } else {
+                               tp->t_rxt_minimum_timeout = min(optval,
+                                   TCP_RXT_MINIMUM_TIMEOUT_LIMIT);
+                               /* convert to milliseconds */
+                               tp->t_rxt_minimum_timeout *= TCP_RETRANSHZ;
+                       }
+                       break;
                default:
                        error = ENOPROTOOPT;
                        break;
@@ -1004,22 +2547,176 @@ tcp_ctloutput(so, sopt)
                case TCP_MAXSEG:
                        optval = tp->t_maxseg;
                        break;
+               case TCP_KEEPALIVE:
+                       if (tp->t_keepidle > 0) {
+                               optval = tp->t_keepidle / TCP_RETRANSHZ;
+                       } else {
+                               optval = tcp_keepidle  / TCP_RETRANSHZ;
+                       }
+                       break;
+               case TCP_KEEPINTVL:
+                       if (tp->t_keepintvl > 0) {
+                               optval = tp->t_keepintvl / TCP_RETRANSHZ;
+                       } else {
+                               optval = tcp_keepintvl / TCP_RETRANSHZ;
+                       }
+                       break;
+               case TCP_KEEPCNT:
+                       if (tp->t_keepcnt > 0) {
+                               optval = tp->t_keepcnt;
+                       } else {
+                               optval = tcp_keepcnt;
+                       }
+                       break;
+               case TCP_KEEPALIVE_OFFLOAD:
+                       optval = !!(inp->inp_flags2 & INP2_KEEPALIVE_OFFLOAD);
+                       break;
                case TCP_NOOPT:
                        optval = tp->t_flags & TF_NOOPT;
                        break;
                case TCP_NOPUSH:
                        optval = tp->t_flags & TF_NOPUSH;
                        break;
+               case TCP_ENABLE_ECN:
+                       optval = (tp->ecn_flags & TE_ECN_MODE_ENABLE) ? 1 : 0;
+                       break;
+               case TCP_ECN_MODE:
+                       if (tp->ecn_flags & TE_ECN_MODE_ENABLE) {
+                               optval = ECN_MODE_ENABLE;
+                       } else if (tp->ecn_flags & TE_ECN_MODE_DISABLE) {
+                               optval = ECN_MODE_DISABLE;
+                       } else {
+                               optval = ECN_MODE_DEFAULT;
+                       }
+                       break;
+               case TCP_CONNECTIONTIMEOUT:
+                       optval = tp->t_keepinit / TCP_RETRANSHZ;
+                       break;
+               case PERSIST_TIMEOUT:
+                       optval = tp->t_persist_timeout / TCP_RETRANSHZ;
+                       break;
+               case TCP_RXT_CONNDROPTIME:
+                       optval = tp->t_rxt_conndroptime / TCP_RETRANSHZ;
+                       break;
+               case TCP_RXT_FINDROP:
+                       optval = tp->t_flagsext & TF_RXTFINDROP;
+                       break;
+               case TCP_NOTIMEWAIT:
+                       optval = (tp->t_flagsext & TF_NOTIMEWAIT) ? 1 : 0;
+                       break;
+               case TCP_FASTOPEN:
+                       if (tp->t_state != TCPS_LISTEN ||
+                           !(tcp_fastopen & TCP_FASTOPEN_SERVER)) {
+                               error = ENOTSUP;
+                               break;
+                       }
+                       optval = tfo_enabled(tp);
+                       break;
+               case TCP_FASTOPEN_FORCE_HEURISTICS:
+                       optval = 0;
+                       break;
+               case TCP_FASTOPEN_FORCE_ENABLE:
+                       optval = (tp->t_flagsext & TF_FASTOPEN_FORCE_ENABLE) ? 1 : 0;
+                       break;
+               case TCP_MEASURE_SND_BW:
+                       optval = tp->t_flagsext & TF_MEASURESNDBW;
+                       break;
+               case TCP_INFO: {
+                       struct tcp_info ti;
+
+                       tcp_fill_info(tp, &ti);
+                       error = sooptcopyout(sopt, &ti, sizeof(struct tcp_info));
+                       goto done;
+                       /* NOT REACHED */
+               }
+               case TCP_CONNECTION_INFO: {
+                       struct tcp_connection_info tci;
+                       tcp_connection_fill_info(tp, &tci);
+                       error = sooptcopyout(sopt, &tci,
+                           sizeof(struct tcp_connection_info));
+                       goto done;
+               }
+               case TCP_MEASURE_BW_BURST: {
+                       struct tcp_measure_bw_burst out = {};
+                       if ((tp->t_flagsext & TF_MEASURESNDBW) == 0 ||
+                           tp->t_bwmeas == NULL) {
+                               error = EINVAL;
+                               break;
+                       }
+                       out.min_burst_size = tp->t_bwmeas->bw_minsizepkts;
+                       out.max_burst_size = tp->t_bwmeas->bw_maxsizepkts;
+                       error = sooptcopyout(sopt, &out, sizeof(out));
+                       goto done;
+               }
+               case TCP_NOTSENT_LOWAT:
+                       if ((so->so_flags & SOF_NOTSENT_LOWAT) != 0) {
+                               optval = tp->t_notsent_lowat;
+                       } else {
+                               optval = 0;
+                       }
+                       break;
+               case TCP_SENDMOREACKS:
+                       if (tp->t_flagsext & TF_NOSTRETCHACK) {
+                               optval = 1;
+                       } else {
+                               optval = 0;
+                       }
+                       break;
+               case TCP_DISABLE_BLACKHOLE_DETECTION:
+                       if (tp->t_flagsext & TF_NOBLACKHOLE_DETECTION) {
+                               optval = 1;
+                       } else {
+                               optval = 0;
+                       }
+                       break;
+               case TCP_PEER_PID: {
+                       pid_t   pid;
+                       error = tcp_lookup_peer_pid_locked(so, &pid);
+                       if (error == 0) {
+                               error = sooptcopyout(sopt, &pid, sizeof(pid));
+                       }
+                       goto done;
+               }
+               case TCP_ADAPTIVE_READ_TIMEOUT:
+                       optval = tp->t_adaptive_rtimo;
+                       break;
+               case TCP_ADAPTIVE_WRITE_TIMEOUT:
+                       optval = tp->t_adaptive_wtimo;
+                       break;
+               case SO_TRAFFIC_MGT_BACKGROUND:
+                       optval = (so->so_flags1 &
+                           SOF1_TRAFFIC_MGT_SO_BACKGROUND) ? 1 : 0;
+                       break;
+               case TCP_NOTIFY_ACKNOWLEDGEMENT: {
+                       struct tcp_notify_ack_complete retid;
+
+                       if (sopt->sopt_valsize != sizeof(retid)) {
+                               error = EINVAL;
+                               break;
+                       }
+                       bzero(&retid, sizeof(retid));
+                       tcp_get_notify_ack_count(tp, &retid);
+                       if (retid.notify_complete_count > 0) {
+                               tcp_get_notify_ack_ids(tp, &retid);
+                       }
+
+                       error = sooptcopyout(sopt, &retid, sizeof(retid));
+                       goto done;
+               }
+               case TCP_RXT_MINIMUM_TIMEOUT:
+                       optval = tp->t_rxt_minimum_timeout / TCP_RETRANSHZ;
+                       break;
                default:
                        error = ENOPROTOOPT;
                        break;
                }
-               if (error == 0)
+               if (error == 0) {
                        error = sooptcopyout(sopt, &optval, sizeof optval);
+               }
                break;
        }
-       splx(s);
-       return (error);
+done:
+       return error;
 }
 
 /*
@@ -1027,63 +2724,130 @@ tcp_ctloutput(so, sopt)
  * sizes, respectively.  These are obsolescent (this information should
  * be set by the route).
  */
-u_long tcp_sendspace = 1024*16;
-SYSCTL_INT(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLFLAG_RW, 
-    &tcp_sendspace , 0, "Maximum outgoing TCP datagram size");
-u_long tcp_recvspace = 1024*16;
-SYSCTL_INT(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLFLAG_RW, 
-    &tcp_recvspace , 0, "Maximum incoming TCP datagram size");
+u_int32_t       tcp_sendspace = 1448 * 256;
+u_int32_t       tcp_recvspace = 1448 * 384;
+
+/* During attach, the size of socket buffer allocated is limited to
+ * sb_max in sbreserve. Disallow setting the tcp send and recv space
+ * to be more than sb_max because that will cause tcp_attach to fail
+ * (see radar 5713060)
+ */
+static int
+sysctl_tcp_sospace(struct sysctl_oid *oidp, __unused void *arg1,
+    int arg2, struct sysctl_req *req)
+{
+#pragma unused(arg2)
+       u_int32_t new_value = 0, *space_p = NULL;
+       int changed = 0, error = 0;
+       u_quad_t sb_effective_max = (sb_max / (MSIZE + MCLBYTES)) * MCLBYTES;
+
+       switch (oidp->oid_number) {
+       case TCPCTL_SENDSPACE:
+               space_p = &tcp_sendspace;
+               break;
+       case TCPCTL_RECVSPACE:
+               space_p = &tcp_recvspace;
+               break;
+       default:
+               return EINVAL;
+       }
+       error = sysctl_io_number(req, *space_p, sizeof(u_int32_t),
+           &new_value, &changed);
+       if (changed) {
+               if (new_value > 0 && new_value <= sb_effective_max) {
+                       *space_p = new_value;
+                       SYSCTL_SKMEM_UPDATE_AT_OFFSET(arg2, new_value);
+               } else {
+                       error = ERANGE;
+               }
+       }
+       return error;
+}
+
+#if SYSCTL_SKMEM
+SYSCTL_PROC(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace,
+    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_sendspace,
+    offsetof(skmem_sysctl, tcp.sendspace), sysctl_tcp_sospace,
+    "IU", "Maximum outgoing TCP datagram size");
+SYSCTL_PROC(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace,
+    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_recvspace,
+    offsetof(skmem_sysctl, tcp.recvspace), sysctl_tcp_sospace,
+    "IU", "Maximum incoming TCP datagram size");
+#else /* SYSCTL_SKMEM */
+SYSCTL_PROC(_net_inet_tcp, TCPCTL_SENDSPACE, sendspace, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+    &tcp_sendspace, 0, &sysctl_tcp_sospace, "IU", "Maximum outgoing TCP datagram size");
+SYSCTL_PROC(_net_inet_tcp, TCPCTL_RECVSPACE, recvspace, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
+    &tcp_recvspace, 0, &sysctl_tcp_sospace, "IU", "Maximum incoming TCP datagram size");
+#endif /* SYSCTL_SKMEM */
 
 /*
  * Attach TCP protocol to socket, allocating
  * internet protocol control block, tcp control block,
  * bufer space, and entering LISTEN state if to accept connections.
+ *
+ * Returns:    0                       Success
+ *     in_pcballoc:ENOBUFS
+ *     in_pcballoc:ENOMEM
+ *     in_pcballoc:???                 [IPSEC specific]
+ *     soreserve:ENOBUFS
  */
 static int
-tcp_attach(so, p)
-       struct socket *so;
-       struct proc *p;
+tcp_attach(struct socket *so, struct proc *p)
 {
-       register struct tcpcb *tp;
+       struct tcpcb *tp;
        struct inpcb *inp;
        int error;
-#if INET6
-       int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6) != NULL;
-#endif
+       int isipv6 = SOCK_CHECK_DOM(so, PF_INET6) != 0;
+
+       error = in_pcballoc(so, &tcbinfo, p);
+       if (error) {
+               return error;
+       }
+
+       inp = sotoinpcb(so);
 
        if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
                error = soreserve(so, tcp_sendspace, tcp_recvspace);
-               if (error)
-                       return (error);
+               if (error) {
+                       return error;
+               }
        }
-       error = in_pcballoc(so, &tcbinfo, p);
-       if (error)
-               return (error);
-       inp = sotoinpcb(so);
-#if INET6
+
+       if (so->so_snd.sb_preconn_hiwat == 0) {
+               soreserve_preconnect(so, 2048);
+       }
+
+       if ((so->so_rcv.sb_flags & SB_USRSIZE) == 0) {
+               so->so_rcv.sb_flags |= SB_AUTOSIZE;
+       }
+       if ((so->so_snd.sb_flags & SB_USRSIZE) == 0) {
+               so->so_snd.sb_flags |= SB_AUTOSIZE;
+       }
+
        if (isipv6) {
                inp->inp_vflag |= INP_IPV6;
-               inp->in6p_hops = -1;    /* use kernel default */
+               inp->in6p_hops = -1;    /* use kernel default */
+       } else {
+               inp->inp_vflag |= INP_IPV4;
        }
-       else
-#endif /* INET6 */
-       inp->inp_vflag |= INP_IPV4;
        tp = tcp_newtcpcb(inp);
-       if (tp == 0) {
-               int nofd = so->so_state & SS_NOFDREF;   /* XXX */
+       if (tp == NULL) {
+               int nofd = so->so_state & SS_NOFDREF;   /* XXX */
 
-               so->so_state &= ~SS_NOFDREF;    /* don't free the socket yet */
-#if INET6
-               if (isipv6)
+               so->so_state &= ~SS_NOFDREF;    /* don't free the socket yet */
+               if (isipv6) {
                        in6_pcbdetach(inp);
-               else
-#endif /* INET6 */
-               in_pcbdetach(inp);
+               } else {
+                       in_pcbdetach(inp);
+               }
                so->so_state |= nofd;
-               return (ENOBUFS);
+               return ENOBUFS;
+       }
+       if (nstat_collect) {
+               nstat_tcp_new_pcb(inp);
        }
        tp->t_state = TCPS_CLOSED;
-       return (0);
+       return 0;
 }
 
 /*
@@ -1095,23 +2859,34 @@ tcp_attach(so, p)
  * send segment to peer (with FIN).
  */
 static struct tcpcb *
-tcp_disconnect(tp)
-       register struct tcpcb *tp;
+tcp_disconnect(struct tcpcb *tp)
 {
        struct socket *so = tp->t_inpcb->inp_socket;
 
-       if (tp->t_state < TCPS_ESTABLISHED)
+       if (so->so_rcv.sb_cc != 0 || tp->t_reassqlen != 0) {
+               return tcp_drop(tp, 0);
+       }
+
+       if (tp->t_state < TCPS_ESTABLISHED) {
                tp = tcp_close(tp);
-       else if ((so->so_options & SO_LINGER) && so->so_linger == 0)
+       } else if ((so->so_options & SO_LINGER) && so->so_linger == 0) {
                tp = tcp_drop(tp, 0);
-       else {
+       else {
                soisdisconnecting(so);
                sbflush(&so->so_rcv);
                tp = tcp_usrclosed(tp);
-               if (tp)
+#if MPTCP
+               /* A reset has been sent but socket exists, do not send FIN */
+               if ((so->so_flags & SOF_MP_SUBFLOW) &&
+                   (tp) && (tp->t_mpflags & TMPF_RESET)) {
+                       return tp;
+               }
+#endif
+               if (tp) {
                        (void) tcp_output(tp);
+               }
        }
-       return (tp);
+       return tp;
 }
 
 /*
@@ -1125,37 +2900,102 @@ tcp_disconnect(tp)
  * We can let the user exit from the close as soon as the FIN is acked.
  */
 static struct tcpcb *
-tcp_usrclosed(tp)
-       register struct tcpcb *tp;
+tcp_usrclosed(struct tcpcb *tp)
 {
-
        switch (tp->t_state) {
-
        case TCPS_CLOSED:
        case TCPS_LISTEN:
-               tp->t_state = TCPS_CLOSED;
+       case TCPS_SYN_SENT:
                tp = tcp_close(tp);
                break;
 
-       case TCPS_SYN_SENT:
        case TCPS_SYN_RECEIVED:
                tp->t_flags |= TF_NEEDFIN;
                break;
 
        case TCPS_ESTABLISHED:
+               DTRACE_TCP4(state__change, void, NULL,
+                   struct inpcb *, tp->t_inpcb,
+                   struct tcpcb *, tp,
+                   int32_t, TCPS_FIN_WAIT_1);
                tp->t_state = TCPS_FIN_WAIT_1;
+               TCP_LOG_CONNECTION_SUMMARY(tp);
                break;
 
        case TCPS_CLOSE_WAIT:
+               DTRACE_TCP4(state__change, void, NULL,
+                   struct inpcb *, tp->t_inpcb,
+                   struct tcpcb *, tp,
+                   int32_t, TCPS_LAST_ACK);
                tp->t_state = TCPS_LAST_ACK;
+               TCP_LOG_CONNECTION_SUMMARY(tp);
                break;
        }
        if (tp && tp->t_state >= TCPS_FIN_WAIT_2) {
                soisdisconnected(tp->t_inpcb->inp_socket);
                /* To prevent the connection hanging in FIN_WAIT_2 forever. */
-               if (tp->t_state == TCPS_FIN_WAIT_2)
-                       tp->t_timer[TCPT_2MSL] = tcp_maxidle;
+               if (tp->t_state == TCPS_FIN_WAIT_2) {
+                       tp->t_timer[TCPT_2MSL] = OFFSET_FROM_START(tp,
+                           TCP_CONN_MAXIDLE(tp));
+               }
        }
-       return (tp);
+       return tp;
 }
 
+void
+tcp_in_cksum_stats(u_int32_t len)
+{
+       tcpstat.tcps_rcv_swcsum++;
+       tcpstat.tcps_rcv_swcsum_bytes += len;
+}
+
+void
+tcp_out_cksum_stats(u_int32_t len)
+{
+       tcpstat.tcps_snd_swcsum++;
+       tcpstat.tcps_snd_swcsum_bytes += len;
+}
+
+void
+tcp_in6_cksum_stats(u_int32_t len)
+{
+       tcpstat.tcps_rcv6_swcsum++;
+       tcpstat.tcps_rcv6_swcsum_bytes += len;
+}
+
+void
+tcp_out6_cksum_stats(u_int32_t len)
+{
+       tcpstat.tcps_snd6_swcsum++;
+       tcpstat.tcps_snd6_swcsum_bytes += len;
+}
+
+int
+tcp_get_mpkl_send_info(struct mbuf *control,
+    struct so_mpkl_send_info *mpkl_send_info)
+{
+       struct cmsghdr *cm;
+
+       if (control == NULL || mpkl_send_info == NULL) {
+               return EINVAL;
+       }
+
+       for (cm = M_FIRST_CMSGHDR(control); cm;
+           cm = M_NXT_CMSGHDR(control, cm)) {
+               if (cm->cmsg_len < sizeof(struct cmsghdr) ||
+                   cm->cmsg_len > control->m_len) {
+                       return EINVAL;
+               }
+               if (cm->cmsg_level != SOL_SOCKET ||
+                   cm->cmsg_type != SCM_MPKL_SEND_INFO) {
+                       continue;
+               }
+               if (cm->cmsg_len != CMSG_LEN(sizeof(struct so_mpkl_send_info))) {
+                       return EINVAL;
+               }
+               memcpy(mpkl_send_info, CMSG_DATA(cm),
+                   sizeof(struct so_mpkl_send_info));
+               return 0;
+       }
+       return ENOMSG;
+}