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/*
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* Copyright (c) 1982, 1986, 1988, 1990, 1993
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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. 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 8.1 (Berkeley) 6/10/93
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* tcp_subr.c,v 1.5 1994/10/08 22:39:58 phk Exp
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*/
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/*
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* Changes and additions relating to SLiRP
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* Copyright (c) 1995 Danny Gasparovski.
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*
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* Please read the file COPYRIGHT for the
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* terms and conditions of the copyright.
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*/
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#include <slirp.h> |
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/* patchable/settable parameters for tcp */
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/* Don't do rfc1323 performance enhancements */
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#define TCP_DO_RFC1323 0 |
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|
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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(void)
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{
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tcp_iss = 1; /* wrong */ |
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tcb.so_next = tcb.so_prev = &tcb; |
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} |
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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, 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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void
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tcp_template(struct tcpcb *tp)
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{
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struct socket *so = tp->t_socket;
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register struct tcpiphdr *n = &tp->t_template; |
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n->ti_mbuf = NULL;
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n->ti_x1 = 0;
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n->ti_pr = IPPROTO_TCP; |
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n->ti_len = htons(sizeof (struct tcpiphdr) - sizeof (struct ip)); |
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n->ti_src = so->so_faddr; |
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n->ti_dst = so->so_laddr; |
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n->ti_sport = so->so_fport; |
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n->ti_dport = so->so_lport; |
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n->ti_seq = 0;
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n->ti_ack = 0;
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n->ti_x2 = 0;
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n->ti_off = 5;
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n->ti_flags = 0;
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n->ti_win = 0;
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n->ti_sum = 0;
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n->ti_urp = 0;
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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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void
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tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m, |
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tcp_seq ack, tcp_seq seq, int flags)
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{
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register int tlen; |
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int win = 0; |
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DEBUG_CALL("tcp_respond");
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DEBUG_ARG("tp = %lx", (long)tp); |
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DEBUG_ARG("ti = %lx", (long)ti); |
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DEBUG_ARG("m = %lx", (long)m); |
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DEBUG_ARG("ack = %u", ack);
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DEBUG_ARG("seq = %u", seq);
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DEBUG_ARG("flags = %x", flags);
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if (tp)
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win = sbspace(&tp->t_socket->so_rcv); |
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if (m == NULL) { |
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if ((m = m_get()) == NULL) |
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return;
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tlen = 0;
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m->m_data += IF_MAXLINKHDR; |
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*mtod(m, struct tcpiphdr *) = *ti;
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ti = mtod(m, struct tcpiphdr *);
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flags = TH_ACK; |
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} else {
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/*
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* ti points into m so the next line is just making
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* the mbuf point to ti
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*/
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m->m_data = (caddr_t)ti; |
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m->m_len = sizeof (struct tcpiphdr); |
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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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xchg(ti->ti_dst.s_addr, ti->ti_src.s_addr, u_int32_t); |
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xchg(ti->ti_dport, ti->ti_sport, u_int16_t); |
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#undef xchg
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} |
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ti->ti_len = htons((u_short)(sizeof (struct tcphdr) + tlen)); |
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tlen += sizeof (struct tcpiphdr); |
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m->m_len = tlen; |
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ti->ti_mbuf = NULL;
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ti->ti_x1 = 0;
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ti->ti_seq = htonl(seq); |
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ti->ti_ack = htonl(ack); |
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ti->ti_x2 = 0;
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ti->ti_off = sizeof (struct tcphdr) >> 2; |
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ti->ti_flags = flags; |
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if (tp)
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ti->ti_win = htons((u_int16_t) (win >> tp->rcv_scale)); |
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else
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ti->ti_win = htons((u_int16_t)win); |
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ti->ti_urp = 0;
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ti->ti_sum = 0;
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ti->ti_sum = cksum(m, tlen); |
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((struct ip *)ti)->ip_len = tlen;
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if(flags & TH_RST)
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((struct ip *)ti)->ip_ttl = MAXTTL;
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else
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((struct ip *)ti)->ip_ttl = IPDEFTTL;
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(void) ip_output((struct socket *)0, m); |
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} |
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/*
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* Create a new TCP control block, making an
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* empty reassembly queue and hooking it to the argument
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* protocol control block.
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*/
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struct tcpcb *
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tcp_newtcpcb(struct socket *so)
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{
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register struct tcpcb *tp; |
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tp = (struct tcpcb *)malloc(sizeof(*tp)); |
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if (tp == NULL) |
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return ((struct tcpcb *)0); |
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memset((char *) tp, 0, sizeof(struct tcpcb)); |
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tp->seg_next = tp->seg_prev = (struct tcpiphdr*)tp;
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tp->t_maxseg = TCP_MSS; |
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tp->t_flags = TCP_DO_RFC1323 ? (TF_REQ_SCALE|TF_REQ_TSTMP) : 0;
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tp->t_socket = so; |
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/*
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* Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
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* rtt estimate. Set rttvar so that srtt + 2 * rttvar gives
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* reasonable initial retransmit time.
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*/
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tp->t_srtt = TCPTV_SRTTBASE; |
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tp->t_rttvar = TCPTV_SRTTDFLT << 2;
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tp->t_rttmin = TCPTV_MIN; |
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TCPT_RANGESET(tp->t_rxtcur, |
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((TCPTV_SRTTBASE >> 2) + (TCPTV_SRTTDFLT << 2)) >> 1, |
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TCPTV_MIN, TCPTV_REXMTMAX); |
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tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; |
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tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; |
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tp->t_state = TCPS_CLOSED; |
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so->so_tcpcb = tp; |
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return (tp);
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} |
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/*
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* Drop a TCP connection, reporting
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* the specified error. If connection is synchronized,
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* then send a RST to peer.
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*/
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struct tcpcb *tcp_drop(struct tcpcb *tp, int err) |
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{
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DEBUG_CALL("tcp_drop");
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DEBUG_ARG("tp = %lx", (long)tp); |
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DEBUG_ARG("errno = %d", errno);
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if (TCPS_HAVERCVDSYN(tp->t_state)) {
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tp->t_state = TCPS_CLOSED; |
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(void) tcp_output(tp);
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STAT(tcpstat.tcps_drops++); |
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} else
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STAT(tcpstat.tcps_conndrops++); |
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return (tcp_close(tp));
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} |
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/*
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* Close a TCP control block:
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* discard all space held by the tcp
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* discard internet protocol block
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* wake up any sleepers
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*/
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struct tcpcb *
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tcp_close(struct tcpcb *tp)
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{
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register struct tcpiphdr *t; |
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struct socket *so = tp->t_socket;
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register struct mbuf *m; |
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DEBUG_CALL("tcp_close");
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DEBUG_ARG("tp = %lx", (long )tp); |
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/* free the reassembly queue, if any */
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t = tcpfrag_list_first(tp); |
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while (!tcpfrag_list_end(t, tp)) {
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t = tcpiphdr_next(t); |
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m = tcpiphdr_prev(t)->ti_mbuf; |
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remque(tcpiphdr2qlink(tcpiphdr_prev(t))); |
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m_freem(m); |
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} |
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free(tp); |
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so->so_tcpcb = NULL;
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/* clobber input socket cache if we're closing the cached connection */
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if (so == tcp_last_so)
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tcp_last_so = &tcb; |
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closesocket(so->s); |
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sbfree(&so->so_rcv); |
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sbfree(&so->so_snd); |
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sofree(so); |
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STAT(tcpstat.tcps_closed++); |
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return ((struct tcpcb *)0); |
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} |
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/*
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* TCP protocol interface to socket abstraction.
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*/
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/*
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* User issued close, and wish to trail through shutdown states:
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* if never received SYN, just forget it. If got a SYN from peer,
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* but haven't sent FIN, then go to FIN_WAIT_1 state to send peer a FIN.
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* If already got a FIN from peer, then almost done; go to LAST_ACK
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* state. In all other cases, have already sent FIN to peer (e.g.
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* after PRU_SHUTDOWN), and just have to play tedious game waiting
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* for peer to send FIN or not respond to keep-alives, etc.
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* We can let the user exit from the close as soon as the FIN is acked.
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*/
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void
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tcp_sockclosed(struct tcpcb *tp)
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{
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DEBUG_CALL("tcp_sockclosed");
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DEBUG_ARG("tp = %lx", (long)tp); |
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switch (tp->t_state) {
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case TCPS_CLOSED:
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case TCPS_LISTEN:
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case TCPS_SYN_SENT:
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tp->t_state = TCPS_CLOSED; |
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tp = tcp_close(tp); |
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break;
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case TCPS_SYN_RECEIVED:
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case TCPS_ESTABLISHED:
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tp->t_state = TCPS_FIN_WAIT_1; |
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break;
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case TCPS_CLOSE_WAIT:
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tp->t_state = TCPS_LAST_ACK; |
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break;
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} |
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if (tp)
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tcp_output(tp); |
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} |
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/*
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* Connect to a host on the Internet
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* Called by tcp_input
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* Only do a connect, the tcp fields will be set in tcp_input
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* return 0 if there's a result of the connect,
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* else return -1 means we're still connecting
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* The return value is almost always -1 since the socket is
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* nonblocking. Connect returns after the SYN is sent, and does
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* not wait for ACK+SYN.
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*/
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int tcp_fconnect(struct socket *so) |
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{
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int ret=0; |
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DEBUG_CALL("tcp_fconnect");
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DEBUG_ARG("so = %lx", (long )so); |
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|
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if( (ret=so->s=socket(AF_INET,SOCK_STREAM,0)) >= 0) { |
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int opt, s=so->s;
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struct sockaddr_in addr;
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fd_nonblock(s); |
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opt = 1;
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setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(opt )); |
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opt = 1;
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setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(opt )); |
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|
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addr.sin_family = AF_INET; |
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if ((so->so_faddr.s_addr & vnetwork_mask.s_addr) == vnetwork_addr.s_addr) {
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/* It's an alias */
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if (so->so_faddr.s_addr == vnameserver_addr.s_addr) {
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addr.sin_addr = dns_addr; |
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} else {
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addr.sin_addr = loopback_addr; |
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} |
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} else
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addr.sin_addr = so->so_faddr; |
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addr.sin_port = so->so_fport; |
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|
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DEBUG_MISC((dfd, " connect()ing, addr.sin_port=%d, "
|
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"addr.sin_addr.s_addr=%.16s\n",
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ntohs(addr.sin_port), inet_ntoa(addr.sin_addr))); |
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/* We don't care what port we get */
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ret = connect(s,(struct sockaddr *)&addr,sizeof (addr)); |
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|
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/*
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* If it's not in progress, it failed, so we just return 0,
|
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* without clearing SS_NOFDREF
|
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*/
|
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soisfconnecting(so); |
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} |
| 362 |
|
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return(ret);
|
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} |
| 365 |
|
| 366 |
/*
|
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* Accept the socket and connect to the local-host
|
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*
|
| 369 |
* We have a problem. The correct thing to do would be
|
| 370 |
* to first connect to the local-host, and only if the
|
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* connection is accepted, then do an accept() here.
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| 372 |
* But, a) we need to know who's trying to connect
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| 373 |
* to the socket to be able to SYN the local-host, and
|
| 374 |
* b) we are already connected to the foreign host by
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* the time it gets to accept(), so... We simply accept
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* here and SYN the local-host.
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*/
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void
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tcp_connect(struct socket *inso)
|
| 380 |
{
|
| 381 |
struct socket *so;
|
| 382 |
struct sockaddr_in addr;
|
| 383 |
socklen_t addrlen = sizeof(struct sockaddr_in); |
| 384 |
struct tcpcb *tp;
|
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int s, opt;
|
| 386 |
|
| 387 |
DEBUG_CALL("tcp_connect");
|
| 388 |
DEBUG_ARG("inso = %lx", (long)inso); |
| 389 |
|
| 390 |
/*
|
| 391 |
* If it's an SS_ACCEPTONCE socket, no need to socreate()
|
| 392 |
* another socket, just use the accept() socket.
|
| 393 |
*/
|
| 394 |
if (inso->so_state & SS_FACCEPTONCE) {
|
| 395 |
/* FACCEPTONCE already have a tcpcb */
|
| 396 |
so = inso; |
| 397 |
} else {
|
| 398 |
if ((so = socreate()) == NULL) { |
| 399 |
/* If it failed, get rid of the pending connection */
|
| 400 |
closesocket(accept(inso->s,(struct sockaddr *)&addr,&addrlen));
|
| 401 |
return;
|
| 402 |
} |
| 403 |
if (tcp_attach(so) < 0) { |
| 404 |
free(so); /* NOT sofree */
|
| 405 |
return;
|
| 406 |
} |
| 407 |
so->so_laddr = inso->so_laddr; |
| 408 |
so->so_lport = inso->so_lport; |
| 409 |
} |
| 410 |
|
| 411 |
(void) tcp_mss(sototcpcb(so), 0); |
| 412 |
|
| 413 |
if ((s = accept(inso->s,(struct sockaddr *)&addr,&addrlen)) < 0) { |
| 414 |
tcp_close(sototcpcb(so)); /* This will sofree() as well */
|
| 415 |
return;
|
| 416 |
} |
| 417 |
fd_nonblock(s); |
| 418 |
opt = 1;
|
| 419 |
setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int)); |
| 420 |
opt = 1;
|
| 421 |
setsockopt(s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int)); |
| 422 |
opt = 1;
|
| 423 |
setsockopt(s,IPPROTO_TCP,TCP_NODELAY,(char *)&opt,sizeof(int)); |
| 424 |
|
| 425 |
so->so_fport = addr.sin_port; |
| 426 |
so->so_faddr = addr.sin_addr; |
| 427 |
/* Translate connections from localhost to the real hostname */
|
| 428 |
if (so->so_faddr.s_addr == 0 || so->so_faddr.s_addr == loopback_addr.s_addr) |
| 429 |
so->so_faddr = vhost_addr; |
| 430 |
|
| 431 |
/* Close the accept() socket, set right state */
|
| 432 |
if (inso->so_state & SS_FACCEPTONCE) {
|
| 433 |
closesocket(so->s); /* If we only accept once, close the accept() socket */
|
| 434 |
so->so_state = SS_NOFDREF; /* Don't select it yet, even though we have an FD */
|
| 435 |
/* if it's not FACCEPTONCE, it's already NOFDREF */
|
| 436 |
} |
| 437 |
so->s = s; |
| 438 |
so->so_state |= SS_INCOMING; |
| 439 |
|
| 440 |
so->so_iptos = tcp_tos(so); |
| 441 |
tp = sototcpcb(so); |
| 442 |
|
| 443 |
tcp_template(tp); |
| 444 |
|
| 445 |
STAT(tcpstat.tcps_connattempt++); |
| 446 |
|
| 447 |
tp->t_state = TCPS_SYN_SENT; |
| 448 |
tp->t_timer[TCPT_KEEP] = TCPTV_KEEP_INIT; |
| 449 |
tp->iss = tcp_iss; |
| 450 |
tcp_iss += TCP_ISSINCR/2;
|
| 451 |
tcp_sendseqinit(tp); |
| 452 |
tcp_output(tp); |
| 453 |
} |
| 454 |
|
| 455 |
/*
|
| 456 |
* Attach a TCPCB to a socket.
|
| 457 |
*/
|
| 458 |
int
|
| 459 |
tcp_attach(struct socket *so)
|
| 460 |
{
|
| 461 |
if ((so->so_tcpcb = tcp_newtcpcb(so)) == NULL) |
| 462 |
return -1; |
| 463 |
|
| 464 |
insque(so, &tcb); |
| 465 |
|
| 466 |
return 0; |
| 467 |
} |
| 468 |
|
| 469 |
/*
|
| 470 |
* Set the socket's type of service field
|
| 471 |
*/
|
| 472 |
static const struct tos_t tcptos[] = { |
| 473 |
{0, 20, IPTOS_THROUGHPUT, 0}, /* ftp data */
|
| 474 |
{21, 21, IPTOS_LOWDELAY, EMU_FTP}, /* ftp control */
|
| 475 |
{0, 23, IPTOS_LOWDELAY, 0}, /* telnet */
|
| 476 |
{0, 80, IPTOS_THROUGHPUT, 0}, /* WWW */
|
| 477 |
{0, 513, IPTOS_LOWDELAY, EMU_RLOGIN|EMU_NOCONNECT}, /* rlogin */
|
| 478 |
{0, 514, IPTOS_LOWDELAY, EMU_RSH|EMU_NOCONNECT}, /* shell */
|
| 479 |
{0, 544, IPTOS_LOWDELAY, EMU_KSH}, /* kshell */
|
| 480 |
{0, 543, IPTOS_LOWDELAY, 0}, /* klogin */
|
| 481 |
{0, 6667, IPTOS_THROUGHPUT, EMU_IRC}, /* IRC */
|
| 482 |
{0, 6668, IPTOS_THROUGHPUT, EMU_IRC}, /* IRC undernet */
|
| 483 |
{0, 7070, IPTOS_LOWDELAY, EMU_REALAUDIO }, /* RealAudio control */
|
| 484 |
{0, 113, IPTOS_LOWDELAY, EMU_IDENT }, /* identd protocol */
|
| 485 |
{0, 0, 0, 0}
|
| 486 |
}; |
| 487 |
|
| 488 |
static struct emu_t *tcpemu = NULL; |
| 489 |
|
| 490 |
/*
|
| 491 |
* Return TOS according to the above table
|
| 492 |
*/
|
| 493 |
u_int8_t |
| 494 |
tcp_tos(struct socket *so)
|
| 495 |
{
|
| 496 |
int i = 0; |
| 497 |
struct emu_t *emup;
|
| 498 |
|
| 499 |
while(tcptos[i].tos) {
|
| 500 |
if ((tcptos[i].fport && (ntohs(so->so_fport) == tcptos[i].fport)) ||
|
| 501 |
(tcptos[i].lport && (ntohs(so->so_lport) == tcptos[i].lport))) {
|
| 502 |
so->so_emu = tcptos[i].emu; |
| 503 |
return tcptos[i].tos;
|
| 504 |
} |
| 505 |
i++; |
| 506 |
} |
| 507 |
|
| 508 |
/* Nope, lets see if there's a user-added one */
|
| 509 |
for (emup = tcpemu; emup; emup = emup->next) {
|
| 510 |
if ((emup->fport && (ntohs(so->so_fport) == emup->fport)) ||
|
| 511 |
(emup->lport && (ntohs(so->so_lport) == emup->lport))) {
|
| 512 |
so->so_emu = emup->emu; |
| 513 |
return emup->tos;
|
| 514 |
} |
| 515 |
} |
| 516 |
|
| 517 |
return 0; |
| 518 |
} |
| 519 |
|
| 520 |
/*
|
| 521 |
* Emulate programs that try and connect to us
|
| 522 |
* This includes ftp (the data connection is
|
| 523 |
* initiated by the server) and IRC (DCC CHAT and
|
| 524 |
* DCC SEND) for now
|
| 525 |
*
|
| 526 |
* NOTE: It's possible to crash SLiRP by sending it
|
| 527 |
* unstandard strings to emulate... if this is a problem,
|
| 528 |
* more checks are needed here
|
| 529 |
*
|
| 530 |
* XXX Assumes the whole command came in one packet
|
| 531 |
*
|
| 532 |
* XXX Some ftp clients will have their TOS set to
|
| 533 |
* LOWDELAY and so Nagel will kick in. Because of this,
|
| 534 |
* we'll get the first letter, followed by the rest, so
|
| 535 |
* we simply scan for ORT instead of PORT...
|
| 536 |
* DCC doesn't have this problem because there's other stuff
|
| 537 |
* in the packet before the DCC command.
|
| 538 |
*
|
| 539 |
* Return 1 if the mbuf m is still valid and should be
|
| 540 |
* sbappend()ed
|
| 541 |
*
|
| 542 |
* NOTE: if you return 0 you MUST m_free() the mbuf!
|
| 543 |
*/
|
| 544 |
int
|
| 545 |
tcp_emu(struct socket *so, struct mbuf *m) |
| 546 |
{
|
| 547 |
u_int n1, n2, n3, n4, n5, n6; |
| 548 |
char buff[257]; |
| 549 |
u_int32_t laddr; |
| 550 |
u_int lport; |
| 551 |
char *bptr;
|
| 552 |
|
| 553 |
DEBUG_CALL("tcp_emu");
|
| 554 |
DEBUG_ARG("so = %lx", (long)so); |
| 555 |
DEBUG_ARG("m = %lx", (long)m); |
| 556 |
|
| 557 |
switch(so->so_emu) {
|
| 558 |
int x, i;
|
| 559 |
|
| 560 |
case EMU_IDENT:
|
| 561 |
/*
|
| 562 |
* Identification protocol as per rfc-1413
|
| 563 |
*/
|
| 564 |
|
| 565 |
{
|
| 566 |
struct socket *tmpso;
|
| 567 |
struct sockaddr_in addr;
|
| 568 |
socklen_t addrlen = sizeof(struct sockaddr_in); |
| 569 |
struct sbuf *so_rcv = &so->so_rcv;
|
| 570 |
|
| 571 |
memcpy(so_rcv->sb_wptr, m->m_data, m->m_len); |
| 572 |
so_rcv->sb_wptr += m->m_len; |
| 573 |
so_rcv->sb_rptr += m->m_len; |
| 574 |
m->m_data[m->m_len] = 0; /* NULL terminate */ |
| 575 |
if (strchr(m->m_data, '\r') || strchr(m->m_data, '\n')) { |
| 576 |
if (sscanf(so_rcv->sb_data, "%u%*[ ,]%u", &n1, &n2) == 2) { |
| 577 |
HTONS(n1); |
| 578 |
HTONS(n2); |
| 579 |
/* n2 is the one on our host */
|
| 580 |
for (tmpso = tcb.so_next; tmpso != &tcb; tmpso = tmpso->so_next) {
|
| 581 |
if (tmpso->so_laddr.s_addr == so->so_laddr.s_addr &&
|
| 582 |
tmpso->so_lport == n2 && |
| 583 |
tmpso->so_faddr.s_addr == so->so_faddr.s_addr && |
| 584 |
tmpso->so_fport == n1) {
|
| 585 |
if (getsockname(tmpso->s,
|
| 586 |
(struct sockaddr *)&addr, &addrlen) == 0) |
| 587 |
n2 = ntohs(addr.sin_port); |
| 588 |
break;
|
| 589 |
} |
| 590 |
} |
| 591 |
} |
| 592 |
so_rcv->sb_cc = snprintf(so_rcv->sb_data, |
| 593 |
so_rcv->sb_datalen, |
| 594 |
"%d,%d\r\n", n1, n2);
|
| 595 |
so_rcv->sb_rptr = so_rcv->sb_data; |
| 596 |
so_rcv->sb_wptr = so_rcv->sb_data + so_rcv->sb_cc; |
| 597 |
} |
| 598 |
m_free(m); |
| 599 |
return 0; |
| 600 |
} |
| 601 |
|
| 602 |
case EMU_FTP: /* ftp */ |
| 603 |
*(m->m_data+m->m_len) = 0; /* NUL terminate for strstr */ |
| 604 |
if ((bptr = (char *)strstr(m->m_data, "ORT")) != NULL) { |
| 605 |
/*
|
| 606 |
* Need to emulate the PORT command
|
| 607 |
*/
|
| 608 |
x = sscanf(bptr, "ORT %u,%u,%u,%u,%u,%u\r\n%256[^\177]",
|
| 609 |
&n1, &n2, &n3, &n4, &n5, &n6, buff); |
| 610 |
if (x < 6) |
| 611 |
return 1; |
| 612 |
|
| 613 |
laddr = htonl((n1 << 24) | (n2 << 16) | (n3 << 8) | (n4)); |
| 614 |
lport = htons((n5 << 8) | (n6));
|
| 615 |
|
| 616 |
if ((so = tcp_listen(INADDR_ANY, 0, laddr, lport, SS_FACCEPTONCE)) == NULL) |
| 617 |
return 1; |
| 618 |
|
| 619 |
n6 = ntohs(so->so_fport); |
| 620 |
|
| 621 |
n5 = (n6 >> 8) & 0xff; |
| 622 |
n6 &= 0xff;
|
| 623 |
|
| 624 |
laddr = ntohl(so->so_faddr.s_addr); |
| 625 |
|
| 626 |
n1 = ((laddr >> 24) & 0xff); |
| 627 |
n2 = ((laddr >> 16) & 0xff); |
| 628 |
n3 = ((laddr >> 8) & 0xff); |
| 629 |
n4 = (laddr & 0xff);
|
| 630 |
|
| 631 |
m->m_len = bptr - m->m_data; /* Adjust length */
|
| 632 |
m->m_len += snprintf(bptr, m->m_hdr.mh_size - m->m_len, |
| 633 |
"ORT %d,%d,%d,%d,%d,%d\r\n%s",
|
| 634 |
n1, n2, n3, n4, n5, n6, x==7?buff:""); |
| 635 |
return 1; |
| 636 |
} else if ((bptr = (char *)strstr(m->m_data, "27 Entering")) != NULL) { |
| 637 |
/*
|
| 638 |
* Need to emulate the PASV response
|
| 639 |
*/
|
| 640 |
x = sscanf(bptr, "27 Entering Passive Mode (%u,%u,%u,%u,%u,%u)\r\n%256[^\177]",
|
| 641 |
&n1, &n2, &n3, &n4, &n5, &n6, buff); |
| 642 |
if (x < 6) |
| 643 |
return 1; |
| 644 |
|
| 645 |
laddr = htonl((n1 << 24) | (n2 << 16) | (n3 << 8) | (n4)); |
| 646 |
lport = htons((n5 << 8) | (n6));
|
| 647 |
|
| 648 |
if ((so = tcp_listen(INADDR_ANY, 0, laddr, lport, SS_FACCEPTONCE)) == NULL) |
| 649 |
return 1; |
| 650 |
|
| 651 |
n6 = ntohs(so->so_fport); |
| 652 |
|
| 653 |
n5 = (n6 >> 8) & 0xff; |
| 654 |
n6 &= 0xff;
|
| 655 |
|
| 656 |
laddr = ntohl(so->so_faddr.s_addr); |
| 657 |
|
| 658 |
n1 = ((laddr >> 24) & 0xff); |
| 659 |
n2 = ((laddr >> 16) & 0xff); |
| 660 |
n3 = ((laddr >> 8) & 0xff); |
| 661 |
n4 = (laddr & 0xff);
|
| 662 |
|
| 663 |
m->m_len = bptr - m->m_data; /* Adjust length */
|
| 664 |
m->m_len += snprintf(bptr, m->m_hdr.mh_size - m->m_len, |
| 665 |
"27 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n%s",
|
| 666 |
n1, n2, n3, n4, n5, n6, x==7?buff:""); |
| 667 |
|
| 668 |
return 1; |
| 669 |
} |
| 670 |
|
| 671 |
return 1; |
| 672 |
|
| 673 |
case EMU_KSH:
|
| 674 |
/*
|
| 675 |
* The kshell (Kerberos rsh) and shell services both pass
|
| 676 |
* a local port port number to carry signals to the server
|
| 677 |
* and stderr to the client. It is passed at the beginning
|
| 678 |
* of the connection as a NUL-terminated decimal ASCII string.
|
| 679 |
*/
|
| 680 |
so->so_emu = 0;
|
| 681 |
for (lport = 0, i = 0; i < m->m_len-1; ++i) { |
| 682 |
if (m->m_data[i] < '0' || m->m_data[i] > '9') |
| 683 |
return 1; /* invalid number */ |
| 684 |
lport *= 10;
|
| 685 |
lport += m->m_data[i] - '0';
|
| 686 |
} |
| 687 |
if (m->m_data[m->m_len-1] == '\0' && lport != 0 && |
| 688 |
(so = tcp_listen(INADDR_ANY, 0, so->so_laddr.s_addr, htons(lport), SS_FACCEPTONCE)) != NULL) |
| 689 |
m->m_len = snprintf(m->m_data, m->m_hdr.mh_size, "%d",
|
| 690 |
ntohs(so->so_fport)) + 1;
|
| 691 |
return 1; |
| 692 |
|
| 693 |
case EMU_IRC:
|
| 694 |
/*
|
| 695 |
* Need to emulate DCC CHAT, DCC SEND and DCC MOVE
|
| 696 |
*/
|
| 697 |
*(m->m_data+m->m_len) = 0; /* NULL terminate the string for strstr */ |
| 698 |
if ((bptr = (char *)strstr(m->m_data, "DCC")) == NULL) |
| 699 |
return 1; |
| 700 |
|
| 701 |
/* The %256s is for the broken mIRC */
|
| 702 |
if (sscanf(bptr, "DCC CHAT %256s %u %u", buff, &laddr, &lport) == 3) { |
| 703 |
if ((so = tcp_listen(INADDR_ANY, 0, htonl(laddr), htons(lport), SS_FACCEPTONCE)) == NULL) |
| 704 |
return 1; |
| 705 |
|
| 706 |
m->m_len = bptr - m->m_data; /* Adjust length */
|
| 707 |
m->m_len += snprintf(bptr, m->m_hdr.mh_size, |
| 708 |
"DCC CHAT chat %lu %u%c\n",
|
| 709 |
(unsigned long)ntohl(so->so_faddr.s_addr), |
| 710 |
ntohs(so->so_fport), 1);
|
| 711 |
} else if (sscanf(bptr, "DCC SEND %256s %u %u %u", buff, &laddr, &lport, &n1) == 4) { |
| 712 |
if ((so = tcp_listen(INADDR_ANY, 0, htonl(laddr), htons(lport), SS_FACCEPTONCE)) == NULL) |
| 713 |
return 1; |
| 714 |
|
| 715 |
m->m_len = bptr - m->m_data; /* Adjust length */
|
| 716 |
m->m_len += snprintf(bptr, m->m_hdr.mh_size, |
| 717 |
"DCC SEND %s %lu %u %u%c\n", buff,
|
| 718 |
(unsigned long)ntohl(so->so_faddr.s_addr), |
| 719 |
ntohs(so->so_fport), n1, 1);
|
| 720 |
} else if (sscanf(bptr, "DCC MOVE %256s %u %u %u", buff, &laddr, &lport, &n1) == 4) { |
| 721 |
if ((so = tcp_listen(INADDR_ANY, 0, htonl(laddr), htons(lport), SS_FACCEPTONCE)) == NULL) |
| 722 |
return 1; |
| 723 |
|
| 724 |
m->m_len = bptr - m->m_data; /* Adjust length */
|
| 725 |
m->m_len += snprintf(bptr, m->m_hdr.mh_size, |
| 726 |
"DCC MOVE %s %lu %u %u%c\n", buff,
|
| 727 |
(unsigned long)ntohl(so->so_faddr.s_addr), |
| 728 |
ntohs(so->so_fport), n1, 1);
|
| 729 |
} |
| 730 |
return 1; |
| 731 |
|
| 732 |
case EMU_REALAUDIO:
|
| 733 |
/*
|
| 734 |
* RealAudio emulation - JP. We must try to parse the incoming
|
| 735 |
* data and try to find the two characters that contain the
|
| 736 |
* port number. Then we redirect an udp port and replace the
|
| 737 |
* number with the real port we got.
|
| 738 |
*
|
| 739 |
* The 1.0 beta versions of the player are not supported
|
| 740 |
* any more.
|
| 741 |
*
|
| 742 |
* A typical packet for player version 1.0 (release version):
|
| 743 |
*
|
| 744 |
* 0000:50 4E 41 00 05
|
| 745 |
* 0000:00 01 00 02 1B D7 00 00 67 E6 6C DC 63 00 12 50 ........g.l.c..P
|
| 746 |
* 0010:4E 43 4C 49 45 4E 54 20 31 30 31 20 41 4C 50 48 NCLIENT 101 ALPH
|
| 747 |
* 0020:41 6C 00 00 52 00 17 72 61 66 69 6C 65 73 2F 76 Al..R..rafiles/v
|
| 748 |
* 0030:6F 61 2F 65 6E 67 6C 69 73 68 5F 2E 72 61 79 42 oa/english_.rayB
|
| 749 |
*
|
| 750 |
* Now the port number 0x1BD7 is found at offset 0x04 of the
|
| 751 |
* Now the port number 0x1BD7 is found at offset 0x04 of the
|
| 752 |
* second packet. This time we received five bytes first and
|
| 753 |
* then the rest. You never know how many bytes you get.
|
| 754 |
*
|
| 755 |
* A typical packet for player version 2.0 (beta):
|
| 756 |
*
|
| 757 |
* 0000:50 4E 41 00 06 00 02 00 00 00 01 00 02 1B C1 00 PNA.............
|
| 758 |
* 0010:00 67 75 78 F5 63 00 0A 57 69 6E 32 2E 30 2E 30 .gux.c..Win2.0.0
|
| 759 |
* 0020:2E 35 6C 00 00 52 00 1C 72 61 66 69 6C 65 73 2F .5l..R..rafiles/
|
| 760 |
* 0030:77 65 62 73 69 74 65 2F 32 30 72 65 6C 65 61 73 website/20releas
|
| 761 |
* 0040:65 2E 72 61 79 53 00 00 06 36 42 e.rayS...6B
|
| 762 |
*
|
| 763 |
* Port number 0x1BC1 is found at offset 0x0d.
|
| 764 |
*
|
| 765 |
* This is just a horrible switch statement. Variable ra tells
|
| 766 |
* us where we're going.
|
| 767 |
*/
|
| 768 |
|
| 769 |
bptr = m->m_data; |
| 770 |
while (bptr < m->m_data + m->m_len) {
|
| 771 |
u_short p; |
| 772 |
static int ra = 0; |
| 773 |
char ra_tbl[4]; |
| 774 |
|
| 775 |
ra_tbl[0] = 0x50; |
| 776 |
ra_tbl[1] = 0x4e; |
| 777 |
ra_tbl[2] = 0x41; |
| 778 |
ra_tbl[3] = 0; |
| 779 |
|
| 780 |
switch (ra) {
|
| 781 |
case 0: |
| 782 |
case 2: |
| 783 |
case 3: |
| 784 |
if (*bptr++ != ra_tbl[ra]) {
|
| 785 |
ra = 0;
|
| 786 |
continue;
|
| 787 |
} |
| 788 |
break;
|
| 789 |
|
| 790 |
case 1: |
| 791 |
/*
|
| 792 |
* We may get 0x50 several times, ignore them
|
| 793 |
*/
|
| 794 |
if (*bptr == 0x50) { |
| 795 |
ra = 1;
|
| 796 |
bptr++; |
| 797 |
continue;
|
| 798 |
} else if (*bptr++ != ra_tbl[ra]) { |
| 799 |
ra = 0;
|
| 800 |
continue;
|
| 801 |
} |
| 802 |
break;
|
| 803 |
|
| 804 |
case 4: |
| 805 |
/*
|
| 806 |
* skip version number
|
| 807 |
*/
|
| 808 |
bptr++; |
| 809 |
break;
|
| 810 |
|
| 811 |
case 5: |
| 812 |
/*
|
| 813 |
* The difference between versions 1.0 and
|
| 814 |
* 2.0 is here. For future versions of
|
| 815 |
* the player this may need to be modified.
|
| 816 |
*/
|
| 817 |
if (*(bptr + 1) == 0x02) |
| 818 |
bptr += 8;
|
| 819 |
else
|
| 820 |
bptr += 4;
|
| 821 |
break;
|
| 822 |
|
| 823 |
case 6: |
| 824 |
/* This is the field containing the port
|
| 825 |
* number that RA-player is listening to.
|
| 826 |
*/
|
| 827 |
lport = (((u_char*)bptr)[0] << 8) |
| 828 |
+ ((u_char *)bptr)[1];
|
| 829 |
if (lport < 6970) |
| 830 |
lport += 256; /* don't know why */ |
| 831 |
if (lport < 6970 || lport > 7170) |
| 832 |
return 1; /* failed */ |
| 833 |
|
| 834 |
/* try to get udp port between 6970 - 7170 */
|
| 835 |
for (p = 6970; p < 7071; p++) { |
| 836 |
if (udp_listen(INADDR_ANY,
|
| 837 |
htons(p), |
| 838 |
so->so_laddr.s_addr, |
| 839 |
htons(lport), |
| 840 |
SS_FACCEPTONCE)) {
|
| 841 |
break;
|
| 842 |
} |
| 843 |
} |
| 844 |
if (p == 7071) |
| 845 |
p = 0;
|
| 846 |
*(u_char *)bptr++ = (p >> 8) & 0xff; |
| 847 |
*(u_char *)bptr++ = p & 0xff;
|
| 848 |
ra = 0;
|
| 849 |
return 1; /* port redirected, we're done */ |
| 850 |
break;
|
| 851 |
|
| 852 |
default:
|
| 853 |
ra = 0;
|
| 854 |
} |
| 855 |
ra++; |
| 856 |
} |
| 857 |
return 1; |
| 858 |
|
| 859 |
default:
|
| 860 |
/* Ooops, not emulated, won't call tcp_emu again */
|
| 861 |
so->so_emu = 0;
|
| 862 |
return 1; |
| 863 |
} |
| 864 |
} |
| 865 |
|
| 866 |
/*
|
| 867 |
* Do misc. config of SLiRP while its running.
|
| 868 |
* Return 0 if this connections is to be closed, 1 otherwise,
|
| 869 |
* return 2 if this is a command-line connection
|
| 870 |
*/
|
| 871 |
int tcp_ctl(struct socket *so) |
| 872 |
{
|
| 873 |
struct sbuf *sb = &so->so_snd;
|
| 874 |
struct ex_list *ex_ptr;
|
| 875 |
int do_pty;
|
| 876 |
|
| 877 |
DEBUG_CALL("tcp_ctl");
|
| 878 |
DEBUG_ARG("so = %lx", (long )so); |
| 879 |
|
| 880 |
if (so->so_faddr.s_addr != vhost_addr.s_addr) {
|
| 881 |
/* Check if it's pty_exec */
|
| 882 |
for (ex_ptr = exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
|
| 883 |
if (ex_ptr->ex_fport == so->so_fport &&
|
| 884 |
so->so_faddr.s_addr == ex_ptr->ex_addr.s_addr) {
|
| 885 |
if (ex_ptr->ex_pty == 3) { |
| 886 |
so->s = -1;
|
| 887 |
so->extra = (void *)ex_ptr->ex_exec;
|
| 888 |
return 1; |
| 889 |
} |
| 890 |
do_pty = ex_ptr->ex_pty; |
| 891 |
DEBUG_MISC((dfd, " executing %s \n",ex_ptr->ex_exec));
|
| 892 |
return fork_exec(so, ex_ptr->ex_exec, do_pty);
|
| 893 |
} |
| 894 |
} |
| 895 |
} |
| 896 |
sb->sb_cc = |
| 897 |
snprintf(sb->sb_wptr, sb->sb_datalen - (sb->sb_wptr - sb->sb_data), |
| 898 |
"Error: No application configured.\r\n");
|
| 899 |
sb->sb_wptr += sb->sb_cc; |
| 900 |
return 0; |
| 901 |
} |