1301 lines
34 KiB
C
1301 lines
34 KiB
C
/*
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* Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95
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* $FreeBSD$
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*/
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#include "opt_compat.h"
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#include "opt_inet6.h"
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#include "opt_ipsec.h"
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#include "opt_tcpdebug.h"
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#include <stddef.h>
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/callout.h>
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#include <sys/kernel.h>
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#include <sys/sysctl.h>
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#include <sys/malloc.h>
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#include <sys/mbuf.h>
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#ifdef INET6
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#include <sys/domain.h>
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#endif
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#include <sys/proc.h>
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#include <sys/socket.h>
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#include <sys/socketvar.h>
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#include <sys/protosw.h>
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#include <vm/vm_zone.h>
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#include <net/route.h>
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#include <net/if.h>
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#define _IP_VHL
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/ip.h>
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#ifdef INET6
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#include <netinet/ip6.h>
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#endif
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#include <netinet/in_pcb.h>
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#ifdef INET6
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#include <netinet6/in6_pcb.h>
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#endif
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#include <netinet/in_var.h>
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#include <netinet/ip_var.h>
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#ifdef INET6
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#include <netinet6/ip6_var.h>
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#endif
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#include <netinet/tcp.h>
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#include <netinet/tcp_fsm.h>
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#include <netinet/tcp_seq.h>
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#include <netinet/tcp_timer.h>
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#include <netinet/tcp_var.h>
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#ifdef INET6
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#include <netinet6/tcp6_var.h>
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#endif
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#include <netinet/tcpip.h>
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#ifdef TCPDEBUG
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#include <netinet/tcp_debug.h>
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#endif
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#include <netinet6/ip6protosw.h>
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#ifdef IPSEC
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#include <netinet6/ipsec.h>
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#endif /*IPSEC*/
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#include <machine/in_cksum.h>
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int tcp_mssdflt = TCP_MSS;
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SYSCTL_INT(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, CTLFLAG_RW,
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&tcp_mssdflt , 0, "Default TCP Maximum Segment Size");
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#ifdef INET6
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int tcp_v6mssdflt = TCP6_MSS;
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SYSCTL_INT(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt,
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CTLFLAG_RW, &tcp_v6mssdflt , 0,
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"Default TCP Maximum Segment Size for IPv6");
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#endif
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#if 0
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static int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ;
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SYSCTL_INT(_net_inet_tcp, TCPCTL_RTTDFLT, rttdflt, CTLFLAG_RW,
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&tcp_rttdflt , 0, "Default maximum TCP Round Trip Time");
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#endif
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static int tcp_do_rfc1323 = 1;
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SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW,
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&tcp_do_rfc1323 , 0, "Enable rfc1323 (high performance TCP) extensions");
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static int tcp_do_rfc1644 = 0;
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SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1644, rfc1644, CTLFLAG_RW,
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&tcp_do_rfc1644 , 0, "Enable rfc1644 (TTCP) extensions");
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static int tcp_tcbhashsize = 0;
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SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RD,
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&tcp_tcbhashsize, 0, "Size of TCP control-block hashtable");
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static int do_tcpdrain = 1;
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SYSCTL_INT(_debug, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0,
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"Enable non Net3 compliant tcp_drain");
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SYSCTL_INT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD,
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&tcbinfo.ipi_count, 0, "Number of active PCBs");
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static void tcp_cleartaocache __P((void));
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static void tcp_notify __P((struct inpcb *, int));
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/*
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* Target size of TCP PCB hash tables. Must be a power of two.
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*
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* Note that this can be overridden by the kernel environment
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* variable net.inet.tcp.tcbhashsize
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*/
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#ifndef TCBHASHSIZE
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#define TCBHASHSIZE 512
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#endif
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/*
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* This is the actual shape of what we allocate using the zone
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* allocator. Doing it this way allows us to protect both structures
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* using the same generation count, and also eliminates the overhead
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* of allocating tcpcbs separately. By hiding the structure here,
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* we avoid changing most of the rest of the code (although it needs
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* to be changed, eventually, for greater efficiency).
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*/
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#define ALIGNMENT 32
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#define ALIGNM1 (ALIGNMENT - 1)
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struct inp_tp {
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union {
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struct inpcb inp;
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char align[(sizeof(struct inpcb) + ALIGNM1) & ~ALIGNM1];
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} inp_tp_u;
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struct tcpcb tcb;
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struct callout inp_tp_rexmt, inp_tp_persist, inp_tp_keep, inp_tp_2msl;
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struct callout inp_tp_delack;
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};
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#undef ALIGNMENT
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#undef ALIGNM1
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/*
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* Tcp initialization
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*/
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void
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tcp_init()
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{
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int hashsize;
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tcp_iss = random(); /* wrong, but better than a constant */
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tcp_ccgen = 1;
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tcp_cleartaocache();
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tcp_delacktime = TCPTV_DELACK;
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tcp_keepinit = TCPTV_KEEP_INIT;
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tcp_keepidle = TCPTV_KEEP_IDLE;
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tcp_keepintvl = TCPTV_KEEPINTVL;
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tcp_maxpersistidle = TCPTV_KEEP_IDLE;
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tcp_msl = TCPTV_MSL;
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LIST_INIT(&tcb);
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tcbinfo.listhead = &tcb;
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TUNABLE_INT_FETCH("net.inet.tcp.tcbhashsize", TCBHASHSIZE, hashsize);
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if (!powerof2(hashsize)) {
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printf("WARNING: TCB hash size not a power of 2\n");
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hashsize = 512; /* safe default */
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}
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tcp_tcbhashsize = hashsize;
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tcbinfo.hashbase = hashinit(hashsize, M_PCB, &tcbinfo.hashmask);
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tcbinfo.porthashbase = hashinit(hashsize, M_PCB,
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&tcbinfo.porthashmask);
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tcbinfo.ipi_zone = zinit("tcpcb", sizeof(struct inp_tp), maxsockets,
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ZONE_INTERRUPT, 0);
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#ifdef INET6
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#define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr))
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#else /* INET6 */
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#define TCP_MINPROTOHDR (sizeof(struct tcpiphdr))
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#endif /* INET6 */
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if (max_protohdr < TCP_MINPROTOHDR)
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max_protohdr = TCP_MINPROTOHDR;
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if (max_linkhdr + TCP_MINPROTOHDR > MHLEN)
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panic("tcp_init");
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#undef TCP_MINPROTOHDR
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}
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/*
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* Create template to be used to send tcp packets on a connection.
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* Call after host entry created, allocates an mbuf and fills
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* in a skeletal tcp/ip header, minimizing the amount of work
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* necessary when the connection is used.
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*/
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struct tcptemp *
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tcp_template(tp)
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struct tcpcb *tp;
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{
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register struct inpcb *inp = tp->t_inpcb;
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register struct mbuf *m;
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register struct tcptemp *n;
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if ((n = tp->t_template) == 0) {
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m = m_get(M_DONTWAIT, MT_HEADER);
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if (m == NULL)
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return (0);
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m->m_len = sizeof (struct tcptemp);
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n = mtod(m, struct tcptemp *);
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}
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#ifdef INET6
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if ((inp->inp_vflag & INP_IPV6) != 0) {
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register struct ip6_hdr *ip6;
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ip6 = (struct ip6_hdr *)n->tt_ipgen;
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ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
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(inp->in6p_flowinfo & IPV6_FLOWINFO_MASK);
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ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
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(IPV6_VERSION & IPV6_VERSION_MASK);
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ip6->ip6_nxt = IPPROTO_TCP;
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ip6->ip6_plen = sizeof(struct tcphdr);
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ip6->ip6_src = inp->in6p_laddr;
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ip6->ip6_dst = inp->in6p_faddr;
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n->tt_t.th_sum = 0;
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} else
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#endif
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{
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struct ip *ip = (struct ip *)n->tt_ipgen;
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bzero(ip, sizeof(struct ip)); /* XXX overkill? */
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ip->ip_vhl = IP_VHL_BORING;
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ip->ip_p = IPPROTO_TCP;
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ip->ip_src = inp->inp_laddr;
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ip->ip_dst = inp->inp_faddr;
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n->tt_t.th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
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htons(sizeof(struct tcphdr) + IPPROTO_TCP));
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}
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n->tt_t.th_sport = inp->inp_lport;
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n->tt_t.th_dport = inp->inp_fport;
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n->tt_t.th_seq = 0;
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n->tt_t.th_ack = 0;
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n->tt_t.th_x2 = 0;
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n->tt_t.th_off = 5;
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n->tt_t.th_flags = 0;
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n->tt_t.th_win = 0;
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n->tt_t.th_urp = 0;
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return (n);
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}
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/*
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* Send a single message to the TCP at address specified by
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* the given TCP/IP header. If m == 0, then we make a copy
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* of the tcpiphdr at ti and send directly to the addressed host.
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* This is used to force keep alive messages out using the TCP
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* template for a connection tp->t_template. If flags are given
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* then we send a message back to the TCP which originated the
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* segment ti, and discard the mbuf containing it and any other
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* attached mbufs.
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*
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* In any case the ack and sequence number of the transmitted
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* segment are as specified by the parameters.
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*
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* NOTE: If m != NULL, then ti must point to *inside* the mbuf.
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*/
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void
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tcp_respond(tp, ipgen, th, m, ack, seq, flags)
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struct tcpcb *tp;
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void *ipgen;
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register struct tcphdr *th;
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register struct mbuf *m;
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tcp_seq ack, seq;
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int flags;
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{
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register int tlen;
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int win = 0;
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struct route *ro = 0;
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struct route sro;
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struct ip *ip;
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struct tcphdr *nth;
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#ifdef INET6
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struct route_in6 *ro6 = 0;
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struct route_in6 sro6;
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struct ip6_hdr *ip6;
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int isipv6;
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#endif /* INET6 */
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int ipflags = 0;
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#ifdef INET6
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isipv6 = IP_VHL_V(((struct ip *)ipgen)->ip_vhl) == 6;
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ip6 = ipgen;
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#endif /* INET6 */
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ip = ipgen;
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if (tp) {
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if (!(flags & TH_RST)) {
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win = sbspace(&tp->t_inpcb->inp_socket->so_rcv);
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if (win > (long)TCP_MAXWIN << tp->rcv_scale)
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win = (long)TCP_MAXWIN << tp->rcv_scale;
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}
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#ifdef INET6
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if (isipv6)
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ro6 = &tp->t_inpcb->in6p_route;
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else
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#endif /* INET6 */
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ro = &tp->t_inpcb->inp_route;
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} else {
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#ifdef INET6
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if (isipv6) {
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ro6 = &sro6;
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bzero(ro6, sizeof *ro6);
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} else
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#endif /* INET6 */
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{
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ro = &sro;
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bzero(ro, sizeof *ro);
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}
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}
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if (m == 0) {
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m = m_gethdr(M_DONTWAIT, MT_HEADER);
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if (m == NULL)
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return;
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#ifdef TCP_COMPAT_42
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tlen = 1;
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#else
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tlen = 0;
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#endif
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m->m_data += max_linkhdr;
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#ifdef INET6
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if (isipv6) {
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bcopy((caddr_t)ip6, mtod(m, caddr_t),
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sizeof(struct ip6_hdr));
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ip6 = mtod(m, struct ip6_hdr *);
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nth = (struct tcphdr *)(ip6 + 1);
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} else
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#endif /* INET6 */
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{
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bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
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ip = mtod(m, struct ip *);
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nth = (struct tcphdr *)(ip + 1);
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}
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bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
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flags = TH_ACK;
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} else {
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m_freem(m->m_next);
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m->m_next = 0;
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m->m_data = (caddr_t)ipgen;
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/* m_len is set later */
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tlen = 0;
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#define xchg(a,b,type) { type t; t=a; a=b; b=t; }
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#ifdef INET6
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if (isipv6) {
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xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
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nth = (struct tcphdr *)(ip6 + 1);
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} else
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#endif /* INET6 */
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{
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xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, n_long);
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nth = (struct tcphdr *)(ip + 1);
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}
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if (th != nth) {
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/*
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* this is usually a case when an extension header
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* exists between the IPv6 header and the
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* TCP header.
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*/
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nth->th_sport = th->th_sport;
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nth->th_dport = th->th_dport;
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}
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xchg(nth->th_dport, nth->th_sport, n_short);
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#undef xchg
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}
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#ifdef INET6
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if (isipv6) {
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ip6->ip6_plen = htons((u_short)(sizeof (struct tcphdr) +
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tlen));
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tlen += sizeof (struct ip6_hdr) + sizeof (struct tcphdr);
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} else
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#endif
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{
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tlen += sizeof (struct tcpiphdr);
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ip->ip_len = tlen;
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ip->ip_ttl = ip_defttl;
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}
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m->m_len = tlen;
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m->m_pkthdr.len = tlen;
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m->m_pkthdr.rcvif = (struct ifnet *) 0;
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nth->th_seq = htonl(seq);
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nth->th_ack = htonl(ack);
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nth->th_x2 = 0;
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nth->th_off = sizeof (struct tcphdr) >> 2;
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nth->th_flags = flags;
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if (tp)
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nth->th_win = htons((u_short) (win >> tp->rcv_scale));
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else
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nth->th_win = htons((u_short)win);
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nth->th_urp = 0;
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#ifdef INET6
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if (isipv6) {
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nth->th_sum = in6_cksum(m, IPPROTO_TCP,
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sizeof(struct ip6_hdr),
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tlen - sizeof(struct ip6_hdr));
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ip6->ip6_hlim = in6_selecthlim(tp ? tp->t_inpcb : NULL,
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ro6 && ro6->ro_rt ?
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ro6->ro_rt->rt_ifp :
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NULL);
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} else
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#endif /* INET6 */
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{
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nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
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htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p)));
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m->m_pkthdr.csum_flags = CSUM_TCP;
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m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
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}
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#ifdef TCPDEBUG
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if (tp == NULL || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG))
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tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0);
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#endif
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#ifdef IPSEC
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if (tp != NULL) {
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m->m_pkthdr.rcvif = (struct ifnet *)tp->t_inpcb->inp_socket;
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ipflags |=
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#ifdef INET6
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isipv6 ? IPV6_SOCKINMRCVIF :
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#endif
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IP_SOCKINMRCVIF;
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}
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#endif
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#ifdef INET6
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if (isipv6) {
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(void)ip6_output(m, NULL, ro6, ipflags, NULL, NULL);
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if (ro6 == &sro6 && ro6->ro_rt) {
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RTFREE(ro6->ro_rt);
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ro6->ro_rt = NULL;
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}
|
|
} else
|
|
#endif /* INET6 */
|
|
{
|
|
(void) ip_output(m, NULL, ro, ipflags, NULL);
|
|
if (ro == &sro && ro->ro_rt) {
|
|
RTFREE(ro->ro_rt);
|
|
ro->ro_rt = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Create a new TCP control block, making an
|
|
* empty reassembly queue and hooking it to the argument
|
|
* protocol control block. The `inp' parameter must have
|
|
* come from the zone allocator set up in tcp_init().
|
|
*/
|
|
struct tcpcb *
|
|
tcp_newtcpcb(inp)
|
|
struct inpcb *inp;
|
|
{
|
|
struct inp_tp *it;
|
|
register struct tcpcb *tp;
|
|
#ifdef INET6
|
|
int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
|
|
#endif /* INET6 */
|
|
|
|
it = (struct inp_tp *)inp;
|
|
tp = &it->tcb;
|
|
bzero((char *) tp, sizeof(struct tcpcb));
|
|
LIST_INIT(&tp->t_segq);
|
|
tp->t_maxseg = tp->t_maxopd =
|
|
#ifdef INET6
|
|
isipv6 ? tcp_v6mssdflt :
|
|
#endif /* INET6 */
|
|
tcp_mssdflt;
|
|
|
|
/* Set up our timeouts. */
|
|
callout_init(tp->tt_rexmt = &it->inp_tp_rexmt);
|
|
callout_init(tp->tt_persist = &it->inp_tp_persist);
|
|
callout_init(tp->tt_keep = &it->inp_tp_keep);
|
|
callout_init(tp->tt_2msl = &it->inp_tp_2msl);
|
|
callout_init(tp->tt_delack = &it->inp_tp_delack);
|
|
|
|
if (tcp_do_rfc1323)
|
|
tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
|
|
if (tcp_do_rfc1644)
|
|
tp->t_flags |= TF_REQ_CC;
|
|
tp->t_inpcb = inp; /* XXX */
|
|
/*
|
|
* Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
|
|
* rtt estimate. Set rttvar so that srtt + 4 * rttvar gives
|
|
* reasonable initial retransmit time.
|
|
*/
|
|
tp->t_srtt = TCPTV_SRTTBASE;
|
|
tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
|
|
tp->t_rttmin = TCPTV_MIN;
|
|
tp->t_rxtcur = TCPTV_RTOBASE;
|
|
tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
|
|
tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
|
|
tp->t_rcvtime = ticks;
|
|
/*
|
|
* IPv4 TTL initialization is necessary for an IPv6 socket as well,
|
|
* because the socket may be bound to an IPv6 wildcard address,
|
|
* which may match an IPv4-mapped IPv6 address.
|
|
*/
|
|
inp->inp_ip_ttl = ip_defttl;
|
|
inp->inp_ppcb = (caddr_t)tp;
|
|
return (tp); /* XXX */
|
|
}
|
|
|
|
/*
|
|
* Drop a TCP connection, reporting
|
|
* the specified error. If connection is synchronized,
|
|
* then send a RST to peer.
|
|
*/
|
|
struct tcpcb *
|
|
tcp_drop(tp, errno)
|
|
register struct tcpcb *tp;
|
|
int errno;
|
|
{
|
|
struct socket *so = tp->t_inpcb->inp_socket;
|
|
|
|
if (TCPS_HAVERCVDSYN(tp->t_state)) {
|
|
tp->t_state = TCPS_CLOSED;
|
|
(void) tcp_output(tp);
|
|
tcpstat.tcps_drops++;
|
|
} else
|
|
tcpstat.tcps_conndrops++;
|
|
if (errno == ETIMEDOUT && tp->t_softerror)
|
|
errno = tp->t_softerror;
|
|
so->so_error = errno;
|
|
return (tcp_close(tp));
|
|
}
|
|
|
|
/*
|
|
* Close a TCP control block:
|
|
* discard all space held by the tcp
|
|
* discard internet protocol block
|
|
* wake up any sleepers
|
|
*/
|
|
struct tcpcb *
|
|
tcp_close(tp)
|
|
register struct tcpcb *tp;
|
|
{
|
|
register struct tseg_qent *q;
|
|
struct inpcb *inp = tp->t_inpcb;
|
|
struct socket *so = inp->inp_socket;
|
|
#ifdef INET6
|
|
int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
|
|
#endif /* INET6 */
|
|
register struct rtentry *rt;
|
|
int dosavessthresh;
|
|
|
|
/*
|
|
* Make sure that all of our timers are stopped before we
|
|
* delete the PCB.
|
|
*/
|
|
callout_stop(tp->tt_rexmt);
|
|
callout_stop(tp->tt_persist);
|
|
callout_stop(tp->tt_keep);
|
|
callout_stop(tp->tt_2msl);
|
|
callout_stop(tp->tt_delack);
|
|
|
|
/*
|
|
* If we got enough samples through the srtt filter,
|
|
* save the rtt and rttvar in the routing entry.
|
|
* 'Enough' is arbitrarily defined as the 16 samples.
|
|
* 16 samples is enough for the srtt filter to converge
|
|
* to within 5% of the correct value; fewer samples and
|
|
* we could save a very bogus rtt.
|
|
*
|
|
* Don't update the default route's characteristics and don't
|
|
* update anything that the user "locked".
|
|
*/
|
|
if (tp->t_rttupdated >= 16) {
|
|
register u_long i = 0;
|
|
#ifdef INET6
|
|
if (isipv6) {
|
|
struct sockaddr_in6 *sin6;
|
|
|
|
if ((rt = inp->in6p_route.ro_rt) == NULL)
|
|
goto no_valid_rt;
|
|
sin6 = (struct sockaddr_in6 *)rt_key(rt);
|
|
if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
|
|
goto no_valid_rt;
|
|
}
|
|
else
|
|
#endif /* INET6 */
|
|
if ((rt = inp->inp_route.ro_rt) == NULL ||
|
|
((struct sockaddr_in *)rt_key(rt))->sin_addr.s_addr
|
|
== INADDR_ANY)
|
|
goto no_valid_rt;
|
|
|
|
if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) {
|
|
i = tp->t_srtt *
|
|
(RTM_RTTUNIT / (hz * TCP_RTT_SCALE));
|
|
if (rt->rt_rmx.rmx_rtt && i)
|
|
/*
|
|
* filter this update to half the old & half
|
|
* the new values, converting scale.
|
|
* See route.h and tcp_var.h for a
|
|
* description of the scaling constants.
|
|
*/
|
|
rt->rt_rmx.rmx_rtt =
|
|
(rt->rt_rmx.rmx_rtt + i) / 2;
|
|
else
|
|
rt->rt_rmx.rmx_rtt = i;
|
|
tcpstat.tcps_cachedrtt++;
|
|
}
|
|
if ((rt->rt_rmx.rmx_locks & RTV_RTTVAR) == 0) {
|
|
i = tp->t_rttvar *
|
|
(RTM_RTTUNIT / (hz * TCP_RTTVAR_SCALE));
|
|
if (rt->rt_rmx.rmx_rttvar && i)
|
|
rt->rt_rmx.rmx_rttvar =
|
|
(rt->rt_rmx.rmx_rttvar + i) / 2;
|
|
else
|
|
rt->rt_rmx.rmx_rttvar = i;
|
|
tcpstat.tcps_cachedrttvar++;
|
|
}
|
|
/*
|
|
* The old comment here said:
|
|
* update the pipelimit (ssthresh) if it has been updated
|
|
* already or if a pipesize was specified & the threshhold
|
|
* got below half the pipesize. I.e., wait for bad news
|
|
* before we start updating, then update on both good
|
|
* and bad news.
|
|
*
|
|
* But we want to save the ssthresh even if no pipesize is
|
|
* specified explicitly in the route, because such
|
|
* connections still have an implicit pipesize specified
|
|
* by the global tcp_sendspace. In the absence of a reliable
|
|
* way to calculate the pipesize, it will have to do.
|
|
*/
|
|
i = tp->snd_ssthresh;
|
|
if (rt->rt_rmx.rmx_sendpipe != 0)
|
|
dosavessthresh = (i < rt->rt_rmx.rmx_sendpipe / 2);
|
|
else
|
|
dosavessthresh = (i < so->so_snd.sb_hiwat / 2);
|
|
if (((rt->rt_rmx.rmx_locks & RTV_SSTHRESH) == 0 &&
|
|
i != 0 && rt->rt_rmx.rmx_ssthresh != 0)
|
|
|| dosavessthresh) {
|
|
/*
|
|
* convert the limit from user data bytes to
|
|
* packets then to packet data bytes.
|
|
*/
|
|
i = (i + tp->t_maxseg / 2) / tp->t_maxseg;
|
|
if (i < 2)
|
|
i = 2;
|
|
i *= (u_long)(tp->t_maxseg +
|
|
#ifdef INET6
|
|
(isipv6 ? sizeof (struct ip6_hdr) +
|
|
sizeof (struct tcphdr) :
|
|
#endif
|
|
sizeof (struct tcpiphdr)
|
|
#ifdef INET6
|
|
)
|
|
#endif
|
|
);
|
|
if (rt->rt_rmx.rmx_ssthresh)
|
|
rt->rt_rmx.rmx_ssthresh =
|
|
(rt->rt_rmx.rmx_ssthresh + i) / 2;
|
|
else
|
|
rt->rt_rmx.rmx_ssthresh = i;
|
|
tcpstat.tcps_cachedssthresh++;
|
|
}
|
|
}
|
|
no_valid_rt:
|
|
/* free the reassembly queue, if any */
|
|
while((q = LIST_FIRST(&tp->t_segq)) != NULL) {
|
|
LIST_REMOVE(q, tqe_q);
|
|
m_freem(q->tqe_m);
|
|
FREE(q, M_TSEGQ);
|
|
}
|
|
if (tp->t_template)
|
|
(void) m_free(dtom(tp->t_template));
|
|
inp->inp_ppcb = NULL;
|
|
soisdisconnected(so);
|
|
#ifdef INET6
|
|
if (INP_CHECK_SOCKAF(so, AF_INET6))
|
|
in6_pcbdetach(inp);
|
|
else
|
|
#endif /* INET6 */
|
|
in_pcbdetach(inp);
|
|
tcpstat.tcps_closed++;
|
|
return ((struct tcpcb *)0);
|
|
}
|
|
|
|
void
|
|
tcp_drain()
|
|
{
|
|
if (do_tcpdrain)
|
|
{
|
|
struct inpcb *inpb;
|
|
struct tcpcb *tcpb;
|
|
struct tseg_qent *te;
|
|
|
|
/*
|
|
* Walk the tcpbs, if existing, and flush the reassembly queue,
|
|
* if there is one...
|
|
* XXX: The "Net/3" implementation doesn't imply that the TCP
|
|
* reassembly queue should be flushed, but in a situation
|
|
* where we're really low on mbufs, this is potentially
|
|
* usefull.
|
|
*/
|
|
for (inpb = tcbinfo.listhead->lh_first; inpb;
|
|
inpb = inpb->inp_list.le_next) {
|
|
if ((tcpb = intotcpcb(inpb))) {
|
|
while ((te = LIST_FIRST(&tcpb->t_segq))
|
|
!= NULL) {
|
|
LIST_REMOVE(te, tqe_q);
|
|
m_freem(te->tqe_m);
|
|
FREE(te, M_TSEGQ);
|
|
}
|
|
}
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Notify a tcp user of an asynchronous error;
|
|
* store error as soft error, but wake up user
|
|
* (for now, won't do anything until can select for soft error).
|
|
*/
|
|
static void
|
|
tcp_notify(inp, error)
|
|
struct inpcb *inp;
|
|
int error;
|
|
{
|
|
register struct tcpcb *tp = (struct tcpcb *)inp->inp_ppcb;
|
|
register struct socket *so = inp->inp_socket;
|
|
|
|
/*
|
|
* Ignore some errors if we are hooked up.
|
|
* If connection hasn't completed, has retransmitted several times,
|
|
* and receives a second error, give up now. This is better
|
|
* than waiting a long time to establish a connection that
|
|
* can never complete.
|
|
*/
|
|
if (tp->t_state == TCPS_ESTABLISHED &&
|
|
(error == EHOSTUNREACH || error == ENETUNREACH ||
|
|
error == EHOSTDOWN)) {
|
|
return;
|
|
} else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
|
|
tp->t_softerror)
|
|
so->so_error = error;
|
|
else
|
|
tp->t_softerror = error;
|
|
wakeup((caddr_t) &so->so_timeo);
|
|
sorwakeup(so);
|
|
sowwakeup(so);
|
|
}
|
|
|
|
static int
|
|
tcp_pcblist SYSCTL_HANDLER_ARGS
|
|
{
|
|
int error, i, n, s;
|
|
struct inpcb *inp, **inp_list;
|
|
inp_gen_t gencnt;
|
|
struct xinpgen xig;
|
|
|
|
/*
|
|
* The process of preparing the TCB list is too time-consuming and
|
|
* resource-intensive to repeat twice on every request.
|
|
*/
|
|
if (req->oldptr == 0) {
|
|
n = tcbinfo.ipi_count;
|
|
req->oldidx = 2 * (sizeof xig)
|
|
+ (n + n/8) * sizeof(struct xtcpcb);
|
|
return 0;
|
|
}
|
|
|
|
if (req->newptr != 0)
|
|
return EPERM;
|
|
|
|
/*
|
|
* OK, now we're committed to doing something.
|
|
*/
|
|
s = splnet();
|
|
gencnt = tcbinfo.ipi_gencnt;
|
|
n = tcbinfo.ipi_count;
|
|
splx(s);
|
|
|
|
xig.xig_len = sizeof xig;
|
|
xig.xig_count = n;
|
|
xig.xig_gen = gencnt;
|
|
xig.xig_sogen = so_gencnt;
|
|
error = SYSCTL_OUT(req, &xig, sizeof xig);
|
|
if (error)
|
|
return error;
|
|
|
|
inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
|
|
if (inp_list == 0)
|
|
return ENOMEM;
|
|
|
|
s = splnet();
|
|
for (inp = tcbinfo.listhead->lh_first, i = 0; inp && i < n;
|
|
inp = inp->inp_list.le_next) {
|
|
if (inp->inp_gencnt <= gencnt && !prison_xinpcb(req->p, inp))
|
|
inp_list[i++] = inp;
|
|
}
|
|
splx(s);
|
|
n = i;
|
|
|
|
error = 0;
|
|
for (i = 0; i < n; i++) {
|
|
inp = inp_list[i];
|
|
if (inp->inp_gencnt <= gencnt) {
|
|
struct xtcpcb xt;
|
|
caddr_t inp_ppcb;
|
|
xt.xt_len = sizeof xt;
|
|
/* XXX should avoid extra copy */
|
|
bcopy(inp, &xt.xt_inp, sizeof *inp);
|
|
inp_ppcb = inp->inp_ppcb;
|
|
if (inp_ppcb != NULL)
|
|
bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp);
|
|
else
|
|
bzero((char *) &xt.xt_tp, sizeof xt.xt_tp);
|
|
if (inp->inp_socket)
|
|
sotoxsocket(inp->inp_socket, &xt.xt_socket);
|
|
error = SYSCTL_OUT(req, &xt, sizeof xt);
|
|
}
|
|
}
|
|
if (!error) {
|
|
/*
|
|
* Give the user an updated idea of our state.
|
|
* If the generation differs from what we told
|
|
* her before, she knows that something happened
|
|
* while we were processing this request, and it
|
|
* might be necessary to retry.
|
|
*/
|
|
s = splnet();
|
|
xig.xig_gen = tcbinfo.ipi_gencnt;
|
|
xig.xig_sogen = so_gencnt;
|
|
xig.xig_count = tcbinfo.ipi_count;
|
|
splx(s);
|
|
error = SYSCTL_OUT(req, &xig, sizeof xig);
|
|
}
|
|
free(inp_list, M_TEMP);
|
|
return error;
|
|
}
|
|
|
|
SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0,
|
|
tcp_pcblist, "S,xtcpcb", "List of active TCP connections");
|
|
|
|
static int
|
|
tcp_getcred SYSCTL_HANDLER_ARGS
|
|
{
|
|
struct sockaddr_in addrs[2];
|
|
struct inpcb *inp;
|
|
int error, s;
|
|
|
|
error = suser(req->p);
|
|
if (error)
|
|
return (error);
|
|
error = SYSCTL_IN(req, addrs, sizeof(addrs));
|
|
if (error)
|
|
return (error);
|
|
s = splnet();
|
|
inp = in_pcblookup_hash(&tcbinfo, addrs[1].sin_addr, addrs[1].sin_port,
|
|
addrs[0].sin_addr, addrs[0].sin_port, 0, NULL);
|
|
if (inp == NULL || inp->inp_socket == NULL) {
|
|
error = ENOENT;
|
|
goto out;
|
|
}
|
|
error = SYSCTL_OUT(req, inp->inp_socket->so_cred, sizeof(struct ucred));
|
|
out:
|
|
splx(s);
|
|
return (error);
|
|
}
|
|
|
|
SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW,
|
|
0, 0, tcp_getcred, "S,ucred", "Get the ucred of a TCP connection");
|
|
|
|
#ifdef INET6
|
|
static int
|
|
tcp6_getcred SYSCTL_HANDLER_ARGS
|
|
{
|
|
struct sockaddr_in6 addrs[2];
|
|
struct inpcb *inp;
|
|
int error, s, mapped = 0;
|
|
|
|
error = suser(req->p);
|
|
if (error)
|
|
return (error);
|
|
error = SYSCTL_IN(req, addrs, sizeof(addrs));
|
|
if (error)
|
|
return (error);
|
|
if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
|
|
if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
|
|
mapped = 1;
|
|
else
|
|
return (EINVAL);
|
|
}
|
|
s = splnet();
|
|
if (mapped == 1)
|
|
inp = in_pcblookup_hash(&tcbinfo,
|
|
*(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12],
|
|
addrs[1].sin6_port,
|
|
*(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12],
|
|
addrs[0].sin6_port,
|
|
0, NULL);
|
|
else
|
|
inp = in6_pcblookup_hash(&tcbinfo, &addrs[1].sin6_addr,
|
|
addrs[1].sin6_port,
|
|
&addrs[0].sin6_addr, addrs[0].sin6_port,
|
|
0, NULL);
|
|
if (inp == NULL || inp->inp_socket == NULL) {
|
|
error = ENOENT;
|
|
goto out;
|
|
}
|
|
error = SYSCTL_OUT(req, inp->inp_socket->so_cred,
|
|
sizeof(struct ucred));
|
|
out:
|
|
splx(s);
|
|
return (error);
|
|
}
|
|
|
|
SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW,
|
|
0, 0,
|
|
tcp6_getcred, "S,ucred", "Get the ucred of a TCP6 connection");
|
|
#endif
|
|
|
|
|
|
void
|
|
tcp_ctlinput(cmd, sa, vip)
|
|
int cmd;
|
|
struct sockaddr *sa;
|
|
void *vip;
|
|
{
|
|
register struct ip *ip = vip;
|
|
register struct tcphdr *th;
|
|
void (*notify) __P((struct inpcb *, int)) = tcp_notify;
|
|
|
|
if (cmd == PRC_QUENCH)
|
|
notify = tcp_quench;
|
|
else if (cmd == PRC_MSGSIZE)
|
|
notify = tcp_mtudisc;
|
|
else if (!PRC_IS_REDIRECT(cmd) &&
|
|
((unsigned)cmd > PRC_NCMDS || inetctlerrmap[cmd] == 0))
|
|
return;
|
|
if (ip) {
|
|
th = (struct tcphdr *)((caddr_t)ip
|
|
+ (IP_VHL_HL(ip->ip_vhl) << 2));
|
|
in_pcbnotify(&tcb, sa, th->th_dport, ip->ip_src, th->th_sport,
|
|
cmd, notify);
|
|
} else
|
|
in_pcbnotify(&tcb, sa, 0, zeroin_addr, 0, cmd, notify);
|
|
}
|
|
|
|
#ifdef INET6
|
|
void
|
|
tcp6_ctlinput(cmd, sa, d)
|
|
int cmd;
|
|
struct sockaddr *sa;
|
|
void *d;
|
|
{
|
|
register struct tcphdr *thp;
|
|
struct tcphdr th;
|
|
void (*notify) __P((struct inpcb *, int)) = tcp_notify;
|
|
struct sockaddr_in6 sa6;
|
|
struct ip6_hdr *ip6;
|
|
struct mbuf *m;
|
|
int off;
|
|
|
|
if (sa->sa_family != AF_INET6 ||
|
|
sa->sa_len != sizeof(struct sockaddr_in6))
|
|
return;
|
|
|
|
if (cmd == PRC_QUENCH)
|
|
notify = tcp_quench;
|
|
else if (cmd == PRC_MSGSIZE)
|
|
notify = tcp_mtudisc;
|
|
else if (!PRC_IS_REDIRECT(cmd) &&
|
|
((unsigned)cmd > PRC_NCMDS || inet6ctlerrmap[cmd] == 0))
|
|
return;
|
|
|
|
/* if the parameter is from icmp6, decode it. */
|
|
if (d != NULL) {
|
|
struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d;
|
|
m = ip6cp->ip6c_m;
|
|
ip6 = ip6cp->ip6c_ip6;
|
|
off = ip6cp->ip6c_off;
|
|
} else {
|
|
m = NULL;
|
|
ip6 = NULL;
|
|
}
|
|
|
|
/*
|
|
* Translate addresses into internal form.
|
|
* Sa check if it is AF_INET6 is done at the top of this funciton.
|
|
*/
|
|
sa6 = *(struct sockaddr_in6 *)sa;
|
|
if (IN6_IS_ADDR_LINKLOCAL(&sa6.sin6_addr) != 0 && m != NULL &&
|
|
m->m_pkthdr.rcvif != NULL)
|
|
sa6.sin6_addr.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
|
|
|
|
if (ip6) {
|
|
/*
|
|
* XXX: We assume that when IPV6 is non NULL,
|
|
* M and OFF are valid.
|
|
*/
|
|
struct in6_addr s;
|
|
|
|
/* translate addresses into internal form */
|
|
memcpy(&s, &ip6->ip6_src, sizeof(s));
|
|
if (IN6_IS_ADDR_LINKLOCAL(&s) != 0 && m != NULL &&
|
|
m->m_pkthdr.rcvif != NULL)
|
|
s.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index);
|
|
|
|
if (m->m_len < off + sizeof(*thp)) {
|
|
/*
|
|
* this should be rare case
|
|
* because now MINCLSIZE is "(MHLEN + 1)",
|
|
* so we compromise on this copy...
|
|
*/
|
|
m_copydata(m, off, sizeof(th), (caddr_t)&th);
|
|
thp = &th;
|
|
} else
|
|
thp = (struct tcphdr *)(mtod(m, caddr_t) + off);
|
|
in6_pcbnotify(&tcb, (struct sockaddr *)&sa6, thp->th_dport,
|
|
&s, thp->th_sport, cmd, notify);
|
|
} else
|
|
in6_pcbnotify(&tcb, (struct sockaddr *)&sa6, 0, &zeroin6_addr,
|
|
0, cmd, notify);
|
|
}
|
|
#endif /* INET6 */
|
|
|
|
/*
|
|
* When a source quench is received, close congestion window
|
|
* to one segment. We will gradually open it again as we proceed.
|
|
*/
|
|
void
|
|
tcp_quench(inp, errno)
|
|
struct inpcb *inp;
|
|
int errno;
|
|
{
|
|
struct tcpcb *tp = intotcpcb(inp);
|
|
|
|
if (tp)
|
|
tp->snd_cwnd = tp->t_maxseg;
|
|
}
|
|
|
|
/*
|
|
* When `need fragmentation' ICMP is received, update our idea of the MSS
|
|
* based on the new value in the route. Also nudge TCP to send something,
|
|
* since we know the packet we just sent was dropped.
|
|
* This duplicates some code in the tcp_mss() function in tcp_input.c.
|
|
*/
|
|
void
|
|
tcp_mtudisc(inp, errno)
|
|
struct inpcb *inp;
|
|
int errno;
|
|
{
|
|
struct tcpcb *tp = intotcpcb(inp);
|
|
struct rtentry *rt;
|
|
struct rmxp_tao *taop;
|
|
struct socket *so = inp->inp_socket;
|
|
int offered;
|
|
int mss;
|
|
#ifdef INET6
|
|
int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) != 0;
|
|
#endif /* INET6 */
|
|
|
|
if (tp) {
|
|
#ifdef INET6
|
|
if (isipv6)
|
|
rt = tcp_rtlookup6(inp);
|
|
else
|
|
#endif /* INET6 */
|
|
rt = tcp_rtlookup(inp);
|
|
if (!rt || !rt->rt_rmx.rmx_mtu) {
|
|
tp->t_maxopd = tp->t_maxseg =
|
|
#ifdef INET6
|
|
isipv6 ? tcp_v6mssdflt :
|
|
#endif /* INET6 */
|
|
tcp_mssdflt;
|
|
return;
|
|
}
|
|
taop = rmx_taop(rt->rt_rmx);
|
|
offered = taop->tao_mssopt;
|
|
mss = rt->rt_rmx.rmx_mtu -
|
|
#ifdef INET6
|
|
(isipv6 ?
|
|
sizeof(struct ip6_hdr) + sizeof(struct tcphdr) :
|
|
#endif /* INET6 */
|
|
sizeof(struct tcpiphdr)
|
|
#ifdef INET6
|
|
)
|
|
#endif /* INET6 */
|
|
;
|
|
|
|
if (offered)
|
|
mss = min(mss, offered);
|
|
/*
|
|
* XXX - The above conditional probably violates the TCP
|
|
* spec. The problem is that, since we don't know the
|
|
* other end's MSS, we are supposed to use a conservative
|
|
* default. But, if we do that, then MTU discovery will
|
|
* never actually take place, because the conservative
|
|
* default is much less than the MTUs typically seen
|
|
* on the Internet today. For the moment, we'll sweep
|
|
* this under the carpet.
|
|
*
|
|
* The conservative default might not actually be a problem
|
|
* if the only case this occurs is when sending an initial
|
|
* SYN with options and data to a host we've never talked
|
|
* to before. Then, they will reply with an MSS value which
|
|
* will get recorded and the new parameters should get
|
|
* recomputed. For Further Study.
|
|
*/
|
|
if (tp->t_maxopd <= mss)
|
|
return;
|
|
tp->t_maxopd = mss;
|
|
|
|
if ((tp->t_flags & (TF_REQ_TSTMP|TF_NOOPT)) == TF_REQ_TSTMP &&
|
|
(tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP)
|
|
mss -= TCPOLEN_TSTAMP_APPA;
|
|
if ((tp->t_flags & (TF_REQ_CC|TF_NOOPT)) == TF_REQ_CC &&
|
|
(tp->t_flags & TF_RCVD_CC) == TF_RCVD_CC)
|
|
mss -= TCPOLEN_CC_APPA;
|
|
#if (MCLBYTES & (MCLBYTES - 1)) == 0
|
|
if (mss > MCLBYTES)
|
|
mss &= ~(MCLBYTES-1);
|
|
#else
|
|
if (mss > MCLBYTES)
|
|
mss = mss / MCLBYTES * MCLBYTES;
|
|
#endif
|
|
if (so->so_snd.sb_hiwat < mss)
|
|
mss = so->so_snd.sb_hiwat;
|
|
|
|
tp->t_maxseg = mss;
|
|
|
|
tcpstat.tcps_mturesent++;
|
|
tp->t_rtttime = 0;
|
|
tp->snd_nxt = tp->snd_una;
|
|
tcp_output(tp);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Look-up the routing entry to the peer of this inpcb. If no route
|
|
* is found and it cannot be allocated the return NULL. This routine
|
|
* is called by TCP routines that access the rmx structure and by tcp_mss
|
|
* to get the interface MTU.
|
|
*/
|
|
struct rtentry *
|
|
tcp_rtlookup(inp)
|
|
struct inpcb *inp;
|
|
{
|
|
struct route *ro;
|
|
struct rtentry *rt;
|
|
|
|
ro = &inp->inp_route;
|
|
rt = ro->ro_rt;
|
|
if (rt == NULL || !(rt->rt_flags & RTF_UP)) {
|
|
/* No route yet, so try to acquire one */
|
|
if (inp->inp_faddr.s_addr != INADDR_ANY) {
|
|
ro->ro_dst.sa_family = AF_INET;
|
|
ro->ro_dst.sa_len = sizeof(ro->ro_dst);
|
|
((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
|
|
inp->inp_faddr;
|
|
rtalloc(ro);
|
|
rt = ro->ro_rt;
|
|
}
|
|
}
|
|
return rt;
|
|
}
|
|
|
|
#ifdef INET6
|
|
struct rtentry *
|
|
tcp_rtlookup6(inp)
|
|
struct inpcb *inp;
|
|
{
|
|
struct route_in6 *ro6;
|
|
struct rtentry *rt;
|
|
|
|
ro6 = &inp->in6p_route;
|
|
rt = ro6->ro_rt;
|
|
if (rt == NULL || !(rt->rt_flags & RTF_UP)) {
|
|
/* No route yet, so try to acquire one */
|
|
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
|
|
ro6->ro_dst.sin6_family = AF_INET6;
|
|
ro6->ro_dst.sin6_len = sizeof(ro6->ro_dst);
|
|
ro6->ro_dst.sin6_addr = inp->in6p_faddr;
|
|
rtalloc((struct route *)ro6);
|
|
rt = ro6->ro_rt;
|
|
}
|
|
}
|
|
return rt;
|
|
}
|
|
#endif /* INET6 */
|
|
|
|
#ifdef IPSEC
|
|
/* compute ESP/AH header size for TCP, including outer IP header. */
|
|
size_t
|
|
ipsec_hdrsiz_tcp(tp)
|
|
struct tcpcb *tp;
|
|
{
|
|
struct inpcb *inp;
|
|
struct mbuf *m;
|
|
size_t hdrsiz;
|
|
struct ip *ip;
|
|
#ifdef INET6
|
|
struct ip6_hdr *ip6;
|
|
#endif /* INET6 */
|
|
struct tcphdr *th;
|
|
|
|
if (!tp || !tp->t_template || !(inp = tp->t_inpcb))
|
|
return 0;
|
|
MGETHDR(m, M_DONTWAIT, MT_DATA);
|
|
if (!m)
|
|
return 0;
|
|
|
|
#ifdef INET6
|
|
if ((inp->inp_vflag & INP_IPV6) != 0) {
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
th = (struct tcphdr *)(ip6 + 1);
|
|
m->m_pkthdr.len = m->m_len =
|
|
sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
|
|
bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip6,
|
|
sizeof(struct ip6_hdr));
|
|
bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th,
|
|
sizeof(struct tcphdr));
|
|
hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
|
|
} else
|
|
#endif /* INET6 */
|
|
{
|
|
ip = mtod(m, struct ip *);
|
|
th = (struct tcphdr *)(ip + 1);
|
|
m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr);
|
|
bcopy((caddr_t)tp->t_template->tt_ipgen, (caddr_t)ip,
|
|
sizeof(struct ip));
|
|
bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th,
|
|
sizeof(struct tcphdr));
|
|
hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
|
|
}
|
|
|
|
m_free(m);
|
|
return hdrsiz;
|
|
}
|
|
#endif /*IPSEC*/
|
|
|
|
/*
|
|
* Return a pointer to the cached information about the remote host.
|
|
* The cached information is stored in the protocol specific part of
|
|
* the route metrics.
|
|
*/
|
|
struct rmxp_tao *
|
|
tcp_gettaocache(inp)
|
|
struct inpcb *inp;
|
|
{
|
|
struct rtentry *rt;
|
|
|
|
#ifdef INET6
|
|
if ((inp->inp_vflag & INP_IPV6) != 0)
|
|
rt = tcp_rtlookup6(inp);
|
|
else
|
|
#endif /* INET6 */
|
|
rt = tcp_rtlookup(inp);
|
|
|
|
/* Make sure this is a host route and is up. */
|
|
if (rt == NULL ||
|
|
(rt->rt_flags & (RTF_UP|RTF_HOST)) != (RTF_UP|RTF_HOST))
|
|
return NULL;
|
|
|
|
return rmx_taop(rt->rt_rmx);
|
|
}
|
|
|
|
/*
|
|
* Clear all the TAO cache entries, called from tcp_init.
|
|
*
|
|
* XXX
|
|
* This routine is just an empty one, because we assume that the routing
|
|
* routing tables are initialized at the same time when TCP, so there is
|
|
* nothing in the cache left over.
|
|
*/
|
|
static void
|
|
tcp_cleartaocache()
|
|
{
|
|
}
|