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 __FBSDID("$FreeBSD$"); 37 38 #ifndef lint 39 static const char sccsid[] = "@(#)look_up.c 8.1 (Berkeley) 6/6/93"; 40 #endif 41 42 #include <sys/types.h> 43 #include <sys/socket.h> 44 #include <protocols/talkd.h> 45 46 #include <errno.h> 47 48 #include "talk_ctl.h" 49 #include "talk.h" 50 51 /* 52 * See if the local daemon has an invitation for us. 53 */ 54 int 55 check_local() 56 { 57 CTL_RESPONSE response; 58 CTL_RESPONSE *rp = &response; 59 60 /* the rest of msg was set up in get_names */ 61 #ifdef MSG_EOR 62 /* copy new style sockaddr to old, swap family (short in old) */ 63 msg.ctl_addr = *(struct osockaddr *)&ctl_addr; 64 msg.ctl_addr.sa_family = htons(ctl_addr.sin_family); 65 #else 66 msg.ctl_addr = *(struct sockaddr *)&ctl_addr; 67 #endif 68 /* must be initiating a talk */ 69 if (!look_for_invite(rp)) 70 return (0); 71 /* 72 * There was an invitation waiting for us, 73 * so connect with the other (hopefully waiting) party 74 */ 75 current_state = "Waiting to connect with caller"; 76 do { 77 if (rp->addr.sa_family != AF_INET) 78 p_error("Response uses invalid network address"); 79 errno = 0; 80 if (connect(sockt, 81 (struct sockaddr *)&rp->addr, sizeof (rp->addr)) != -1) 82 return (1); 83 } while (errno == EINTR); 84 if (errno == ECONNREFUSED) { 85 /* 86 * The caller gave up, but his invitation somehow 87 * was not cleared. Clear it and initiate an 88 * invitation. (We know there are no newer invitations, 89 * the talkd works LIFO.) 90 */ 91 ctl_transact(his_machine_addr, msg, DELETE, rp); 92 close(sockt); 93 open_sockt(); 94 return (0); 95 } 96 p_error("Unable to connect with initiator"); 97 /*NOTREACHED*/ 98 return (0); 99 } 100 101 /* 102 * Look for an invitation on 'machine' 103 */ 104 int 105 look_for_invite(rp) 106 CTL_RESPONSE *rp; 107 { 108 current_state = "Checking for invitation on caller's machine"; 109 ctl_transact(his_machine_addr, msg, LOOK_UP, rp); 110 /* the switch is for later options, such as multiple invitations */ 111 switch (rp->answer) { 112 113 case SUCCESS: 114 msg.id_num = htonl(rp->id_num); 115 return (1); 116 117 default: 118 /* there wasn't an invitation waiting for us */ 119 return (0); 120 } 121 } 122