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