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/* $OpenBSD: invite.c,v 1.15 2013/03/11 17:40:11 deraadt Exp $ */
/* $NetBSD: invite.c,v 1.3 1994/12/09 02:14:18 jtc Exp $ */
/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "talk.h"
#include <arpa/inet.h>
#include <sys/time.h>
#include <netdb.h>
#include <errno.h>
#include <setjmp.h>
#include <unistd.h>
#include "talk_ctl.h"
#define STRING_LENGTH 158
/*
* There wasn't an invitation waiting, so send a request containing
* our sockt address to the remote talk daemon so it can invite
* him
*/
/*
* The msg.id's for the invitations
* on the local and remote machines.
* These are used to delete the
* invitations.
*/
int local_id, remote_id;
jmp_buf invitebuf;
void
invite_remote(void)
{
int new_sockt;
struct itimerval itimer;
CTL_RESPONSE response;
struct sockaddr rp;
socklen_t rplen = sizeof(struct sockaddr);
struct hostent *rphost;
char rname[STRING_LENGTH];
itimer.it_value.tv_sec = RING_WAIT;
itimer.it_value.tv_usec = 0;
itimer.it_interval = itimer.it_value;
if (listen(sockt, 5) != 0)
quit("Error on attempt to listen for caller", 1);
#ifdef MSG_EOR
/* copy new style sockaddr to old, swap family (short in old) */
msg.addr = *(struct osockaddr *)&my_addr; /* XXX new to old style*/
msg.addr.sa_family = htons(my_addr.sin_family);
#else
msg.addr = *(struct sockaddr *)&my_addr;
#endif
msg.id_num = htonl(-1); /* an impossible id_num */
invitation_waiting = 1;
announce_invite();
/*
* Shut off the automatic messages for a while,
* so we can use the interrupt timer to resend the invitation.
* We no longer turn automatic messages back on to avoid a bonus
* message after we've connected; this is okay even though end_msgs()
* gets called again in main().
*/
end_msgs();
setitimer(ITIMER_REAL, &itimer, (struct itimerval *)0);
message("Waiting for your party to respond");
signal(SIGALRM, re_invite);
(void) setjmp(invitebuf);
while ((new_sockt = accept(sockt, &rp, &rplen)) == -1) {
if (errno == EINTR || errno == EWOULDBLOCK ||
errno == ECONNABORTED)
continue;
quit("Unable to connect with your party", 1);
}
close(sockt);
sockt = new_sockt;
/*
* Have the daemons delete the invitations now that we
* have connected.
*/
msg.id_num = htonl(local_id);
ctl_transact(my_machine_addr, msg, DELETE, &response);
msg.id_num = htonl(remote_id);
ctl_transact(his_machine_addr, msg, DELETE, &response);
invitation_waiting = 0;
/*
* Check to see if the other guy is coming from the machine
* we expect.
*/
if (his_machine_addr.s_addr !=
((struct sockaddr_in *)&rp)->sin_addr.s_addr) {
rphost = gethostbyaddr((char *) &((struct sockaddr_in
*)&rp)->sin_addr, sizeof(struct in_addr), AF_INET);
if (rphost)
snprintf(rname, STRING_LENGTH,
"Answering talk request from %s@%s", msg.r_name,
rphost->h_name);
else
snprintf(rname, STRING_LENGTH,
"Answering talk request from %s@%s", msg.r_name,
inet_ntoa(((struct sockaddr_in *)&rp)->sin_addr));
message(rname);
}
}
/*
* Routine called on interrupt to re-invite the callee
*/
void
re_invite(int dummy)
{
message("Ringing your party again");
/* force a re-announce */
msg.id_num = htonl(remote_id + 1);
announce_invite();
longjmp(invitebuf, 1);
}
static char *answers[] = {
"answer #0", /* SUCCESS */
"Your party is not logged on", /* NOT_HERE */
"Target machine is too confused to talk to us", /* FAILED */
"Target machine does not recognize us", /* MACHINE_UNKNOWN */
"Your party is refusing messages", /* PERMISSION_REFUSED */
"Target machine can not handle remote talk", /* UNKNOWN_REQUEST */
"Target machine indicates protocol mismatch", /* BADVERSION */
"Target machine indicates protocol botch (addr)",/* BADADDR */
"Target machine indicates protocol botch (ctl_addr)",/* BADCTLADDR */
};
#define NANSWERS (sizeof (answers) / sizeof (answers[0]))
/*
* Transmit the invitation and process the response
*/
void
announce_invite(void)
{
CTL_RESPONSE response;
current_state = "Trying to connect to your party's talk daemon";
ctl_transact(his_machine_addr, msg, ANNOUNCE, &response);
remote_id = response.id_num;
if (response.answer != SUCCESS)
quit(response.answer < NANSWERS ? answers[response.answer] : NULL, 0);
/* leave the actual invitation on my talk daemon */
ctl_transact(my_machine_addr, msg, LEAVE_INVITE, &response);
local_id = response.id_num;
}
/*
* Tell the daemon to remove your invitation
*/
void
send_delete(void)
{
msg.type = DELETE;
/*
* This is just a extra clean up, so just send it
* and don't wait for an answer
*/
msg.id_num = htonl(remote_id);
daemon_addr.sin_addr = his_machine_addr;
if (sendto(ctl_sockt, &msg, sizeof (msg), 0,
(struct sockaddr *)&daemon_addr,
sizeof (daemon_addr)) != sizeof(msg))
warn("send_delete (remote)");
msg.id_num = htonl(local_id);
daemon_addr.sin_addr = my_machine_addr;
if (sendto(ctl_sockt, &msg, sizeof (msg), 0,
(struct sockaddr *)&daemon_addr,
sizeof (daemon_addr)) != sizeof (msg))
warn("send_delete (local)");
}
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