a8e556405f
remote peer will be connected through. This avoids the ``Checking for invitation on caller's machine'' problem for multi-homed hosts. Thanks to: Garrett, for his `find_interface' example
119 lines
3.8 KiB
C
119 lines
3.8 KiB
C
/*
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* Copyright (c) 1983, 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. 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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#ifndef lint
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static char sccsid[] = "@(#)look_up.c 8.1 (Berkeley) 6/6/93";
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#endif /* not lint */
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <netinet/in.h>
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#include <protocols/talkd.h>
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#include <errno.h>
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#include "talk_ctl.h"
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#include "talk.h"
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/*
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* See if the local daemon has an invitation for us.
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*/
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int
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check_local()
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{
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CTL_RESPONSE response;
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register CTL_RESPONSE *rp = &response;
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/* the rest of msg was set up in get_names */
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#ifdef MSG_EOR
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/* copy new style sockaddr to old, swap family (short in old) */
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msg.ctl_addr = *(struct osockaddr *)&ctl_addr;
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msg.ctl_addr.sa_family = htons(ctl_addr.sin_family);
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#else
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msg.ctl_addr = *(struct sockaddr *)&ctl_addr;
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#endif
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/* must be initiating a talk */
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if (!look_for_invite(rp))
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return (0);
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/*
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* There was an invitation waiting for us,
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* so connect with the other (hopefully waiting) party
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*/
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current_state = "Waiting to connect with caller";
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do {
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if (rp->addr.sa_family != AF_INET)
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p_error("Response uses invalid network address");
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errno = 0;
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if (connect(sockt,
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(struct sockaddr *)&rp->addr, sizeof (rp->addr)) != -1)
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return (1);
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} while (errno == EINTR);
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if (errno == ECONNREFUSED) {
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/*
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* The caller gave up, but his invitation somehow
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* was not cleared. Clear it and initiate an
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* invitation. (We know there are no newer invitations,
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* the talkd works LIFO.)
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*/
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ctl_transact(his_machine_addr, msg, DELETE, rp);
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close(sockt);
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open_sockt();
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return (0);
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}
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p_error("Unable to connect with initiator");
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/*NOTREACHED*/
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return (0);
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}
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/*
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* Look for an invitation on 'machine'
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*/
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int
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look_for_invite(rp)
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CTL_RESPONSE *rp;
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{
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struct in_addr machine_addr;
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current_state = "Checking for invitation on caller's machine";
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ctl_transact(his_machine_addr, msg, LOOK_UP, rp);
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/* the switch is for later options, such as multiple invitations */
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switch (rp->answer) {
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case SUCCESS:
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msg.id_num = htonl(rp->id_num);
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return (1);
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default:
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/* there wasn't an invitation waiting for us */
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return (0);
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}
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}
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