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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
* Copyright 2007 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T
* All Rights Reserved.
*/
/*
* University Copyright- Copyright (c) 1982, 1986, 1988
* The Regents of the University of California.
* All Rights Reserved.
*
* University Acknowledgment- Portions of this document are derived from
* software developed by the University of California, Berkeley, and its
* contributors.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* process.c handles the requests, which can be of three types:
*
* ANNOUNCE - announce to a user that a talk is wanted
*
* LEAVE_INVITE - insert the request into the table
*
* LOOK_UP - look up to see if a request is waiting in
* in the table for the local user
*
* DELETE - delete invitation
*
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <syslog.h>
#include <string.h>
#include <utmpx.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include "talkd_impl.h"
static void do_announce(CTL_MSG *request, CTL_RESPONSE *response);
static int find_user(char *name, char *tty);
void
process_request(CTL_MSG *request, CTL_RESPONSE *response)
{
CTL_MSG *ptr;
response->type = request->type;
response->id_num = 0;
/*
* Check if any of the strings within the request structure aren't
* NUL terminated, and if so don't bother processing the request
* further.
*/
if ((memchr(request->l_name, '\0', sizeof (request->l_name)) == NULL) ||
(memchr(request->r_name, '\0', sizeof (request->r_name)) == NULL) ||
(memchr(request->r_tty, '\0', sizeof (request->r_tty)) == NULL)) {
response->answer = FAILED;
openlog("talk", 0, LOG_AUTH);
syslog(LOG_CRIT, "malformed talk request\n");
closelog();
return;
}
switch (request->type) {
case ANNOUNCE :
do_announce(request, response);
break;
case LEAVE_INVITE :
ptr = find_request(request);
if (ptr != NULL) {
response->id_num = ptr->id_num;
response->answer = SUCCESS;
} else {
insert_table(request, response);
}
break;
case LOOK_UP :
ptr = find_match(request);
if (ptr != NULL) {
response->id_num = ptr->id_num;
response->addr = ptr->addr;
response->answer = SUCCESS;
} else {
response->answer = NOT_HERE;
}
break;
case DELETE :
response->answer = delete_invite(request->id_num);
break;
default :
response->answer = UNKNOWN_REQUEST;
break;
}
}
static void
do_announce(CTL_MSG *request, CTL_RESPONSE *response)
{
struct hostent *hp;
CTL_MSG *ptr;
int result;
/*
* See if the user is logged.
*/
result = find_user(request->r_name, request->r_tty);
if (result != SUCCESS) {
response->answer = result;
return;
}
hp = gethostbyaddr((const char *)&request->ctl_addr.sin_addr,
sizeof (struct in_addr), AF_INET);
if (hp == NULL) {
response->answer = MACHINE_UNKNOWN;
return;
}
ptr = find_request(request);
if (ptr == NULL) {
insert_table(request, response);
response->answer = announce(request, hp->h_name);
} else if (request->id_num > ptr->id_num) {
/*
* This is an explicit re-announce, so update the id_num
* field to avoid duplicates and re-announce the talk.
*/
ptr->id_num = response->id_num = new_id();
response->answer = announce(request, hp->h_name);
} else {
/* a duplicated request, so ignore it */
response->id_num = ptr->id_num;
response->answer = SUCCESS;
}
}
/*
* Search utmp for the local user.
*/
static int
find_user(char *name, char *tty)
{
struct utmpx *ubuf;
int tfd;
char dev[MAXPATHLEN];
struct stat stbuf;
int problem = NOT_HERE;
setutxent(); /* reset the utmpx file */
while (ubuf = getutxent()) {
if (ubuf->ut_type == USER_PROCESS &&
strncmp(ubuf->ut_user, name, sizeof (ubuf->ut_user)) == 0) {
/*
* Check if this entry is really a tty.
*/
(void) snprintf(dev, sizeof (dev), "/dev/%.*s",
sizeof (ubuf->ut_line), ubuf->ut_line);
if ((tfd = open(dev, O_WRONLY|O_NOCTTY)) == -1) {
continue;
}
if (!isatty(tfd)) {
(void) close(tfd);
openlog("talk", 0, LOG_AUTH);
syslog(LOG_CRIT, "%.*s in utmp is not a tty\n",
sizeof (ubuf->ut_line), ubuf->ut_line);
closelog();
continue;
}
if (*tty == '\0') {
/*
* No particular tty was requested.
*/
if (fstat(tfd, &stbuf) < 0 ||
(stbuf.st_mode&020) == 0) {
(void) close(tfd);
problem = PERMISSION_DENIED;
continue;
}
(void) close(tfd);
(void) strlcpy(tty, ubuf->ut_line, TTY_SIZE);
endutxent(); /* close the utmpx file */
return (SUCCESS);
}
(void) close(tfd);
if (strcmp(ubuf->ut_line, tty) == 0) {
endutxent(); /* close the utmpx file */
return (SUCCESS);
}
}
}
endutxent(); /* close the utmpx file */
return (problem);
}
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