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/* $NetBSD: get_names.c,v 1.16 2014/03/29 20:16:09 dholland Exp $ */
/*
* Copyright (c) 1983-2003, 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:
*
* + Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* + 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.
* + Neither the name of the University of California, San Francisco 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 COPYRIGHT HOLDERS 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 COPYRIGHT
* OWNER 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 <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: get_names.c,v 1.16 2014/03/29 20:16:09 dholland Exp $");
#endif /* not lint */
#if defined(TALK_43) || defined(TALK_42)
#include <sys/param.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <assert.h>
#include "hunt.h"
#include "talk_ctl.h"
static char hostname[MAXHOSTNAMELEN + 1];
char *my_machine_name;
/*
* Determine the local user and machine
*/
void
get_local_name(const char *my_name)
{
struct hostent *hp;
struct servent *sp;
/* Load these useful values into the standard message header */
msg.id_num = 0;
(void) strncpy(msg.l_name, my_name, NAME_SIZE);
msg.l_name[NAME_SIZE - 1] = '\0';
msg.r_tty[0] = '\0';
msg.pid = getpid();
#ifdef TALK_43
msg.vers = TALK_VERSION;
msg.addr.sa_family = htons(AF_INET);
msg.ctl_addr.sa_family = htons(AF_INET);
#else
msg.addr.sin_family = htons(AF_INET);
msg.ctl_addr.sin_family = htons(AF_INET);
#endif
(void)gethostname(hostname, sizeof (hostname));
hostname[sizeof(hostname) - 1] = '\0';
my_machine_name = hostname;
/* look up the address of the local host */
hp = gethostbyname(my_machine_name);
if (hp == (struct hostent *) 0) {
#ifdef LOG
syslog(LOG_ERR,
"This machine doesn't exist. Boy, am I confused!");
#else
perror("This machine doesn't exist. Boy, am I confused!");
#endif
exit(1);
}
memcpy(&my_machine_addr, hp->h_addr, hp->h_length);
/* find the daemon portal */
#ifdef TALK_43
sp = getservbyname("ntalk", "udp");
#else
sp = getservbyname("talk", "udp");
#endif
if (sp == 0) {
#ifdef LOG
syslog(LOG_ERR, "This machine doesn't support talk");
#else
perror("This machine doesn't support talk");
#endif
exit(1);
}
daemon_port = sp->s_port;
}
/*
* Determine the remote user and machine
*/
int
get_remote_name(char *his_address)
{
const char *his_name;
const char *his_machine_name;
char *ptr;
struct addrinfo ai0, *ai;
struct sockaddr_in *sin;
/* check for, and strip out, the machine name of the target */
for (ptr = his_address; *ptr != '\0' && *ptr != '@' && *ptr != ':'
&& *ptr != '!' && *ptr != '.'; ptr++)
continue;
if (*ptr == '\0') {
/* this is a local to local talk */
his_name = his_address;
his_machine_name = my_machine_name;
his_machine_addr = my_machine_addr;
} else {
if (*ptr == '@') {
/* user@host */
his_name = his_address;
his_machine_name = ptr + 1;
} else {
/* host.user or host!user or host:user */
his_name = ptr + 1;
his_machine_name = his_address;
}
*ptr = '\0';
/*
* Look up the address of the recipient's machine.
* Since this is used for sending udp talk packets,
* it has to be AF_INET.
*/
ai0.ai_flags = 0;
ai0.ai_family = AF_INET;
ai0.ai_socktype = SOCK_DGRAM;
ai0.ai_protocol = IPPROTO_UDP;
ai0.ai_addrlen = 0;
ai0.ai_addr = NULL;
ai0.ai_canonname = NULL;
ai0.ai_next = NULL;
if (getaddrinfo(his_machine_name, NULL, &ai0, &ai) != 0) {
return 0;
}
assert(ai->ai_family == AF_INET);
assert(ai->ai_socktype == SOCK_DGRAM);
assert(ai->ai_protocol == IPPROTO_UDP);
assert(ai->ai_addrlen == sizeof(his_machine_addr));
assert(ai->ai_addr != NULL);
sin = (struct sockaddr_in *)ai->ai_addr;
his_machine_addr = sin->sin_addr;
freeaddrinfo(ai);
}
/* Load these useful values into the standard message header */
(void) strncpy(msg.r_name, his_name, NAME_SIZE);
msg.r_name[NAME_SIZE - 1] = '\0';
return 1;
}
#endif
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