1/* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#include <sys/cdefs.h> 35 36#ifndef __APPLE__ 37__FBSDID("$FreeBSD: src/usr.bin/talk/look_up.c,v 1.8 2005/02/09 09:13:36 stefanf Exp $"); 38 39#ifndef lint 40static const char sccsid[] = "@(#)look_up.c 8.1 (Berkeley) 6/6/93"; 41#endif 42#endif /* __APPLE__ */ 43 44#include <sys/types.h> 45#include <sys/socket.h> 46#include <protocols/talkd.h> 47 48#include <errno.h> 49#include <string.h> 50 51#include "talk_ctl.h" 52#include "talk.h" 53 54/* 55 * See if the local daemon has an invitation for us. 56 */ 57int 58check_local() 59{ 60 CTL_RESPONSE response; 61 CTL_RESPONSE *rp = &response; 62 struct sockaddr addr; 63 64 /* the rest of msg was set up in get_names */ 65#ifdef MSG_EOR 66 /* copy new style sockaddr to old, swap family (short in old) */ 67 msg.ctl_addr = *(struct osockaddr *)&ctl_addr; 68 msg.ctl_addr.sa_family = htons(ctl_addr.sin_family); 69#else 70 msg.ctl_addr = *(struct sockaddr *)&ctl_addr; 71#endif 72 /* must be initiating a talk */ 73 if (!look_for_invite(rp)) 74 return (0); 75 /* 76 * There was an invitation waiting for us, 77 * so connect with the other (hopefully waiting) party 78 */ 79 current_state = "Waiting to connect with caller"; 80 do { 81 if (rp->addr.sa_family != AF_INET) 82 p_error("Response uses invalid network address"); 83 (void)memcpy(&addr, &rp->addr.sa_family, sizeof(addr)); 84 addr.sa_family = rp->addr.sa_family; 85 addr.sa_len = sizeof(addr); 86 errno = 0; 87 if (connect(sockt, &addr, sizeof(addr)) != -1) 88 return (1); 89 } while (errno == EINTR); 90 if (errno == ECONNREFUSED) { 91 /* 92 * The caller gave up, but his invitation somehow 93 * was not cleared. Clear it and initiate an 94 * invitation. (We know there are no newer invitations, 95 * the talkd works LIFO.) 96 */ 97 ctl_transact(his_machine_addr, msg, DELETE, rp); 98 close(sockt); 99 open_sockt(); 100 return (0); 101 } 102 p_error("Unable to connect with initiator"); 103 /*NOTREACHED*/ 104 return (0); 105} 106 107/* 108 * Look for an invitation on 'machine' 109 */ 110int 111look_for_invite(rp) 112 CTL_RESPONSE *rp; 113{ 114 current_state = "Checking for invitation on caller's machine"; 115 ctl_transact(his_machine_addr, msg, LOOK_UP, rp); 116 /* the switch is for later options, such as multiple invitations */ 117 switch (rp->answer) { 118 119 case SUCCESS: 120 msg.id_num = htonl(rp->id_num); 121 return (1); 122 123 default: 124 /* there wasn't an invitation waiting for us */ 125 return (0); 126 } 127} 128