1 /* $OpenBSD: invite.c,v 1.17 2016/03/16 15:41:11 krw Exp $ */ 2 /* $NetBSD: invite.c,v 1.3 1994/12/09 02:14:18 jtc Exp $ */ 3 4 /* 5 * Copyright (c) 1983, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <sys/socket.h> 34 #include <arpa/inet.h> 35 36 #include <err.h> 37 #include <errno.h> 38 #include <netdb.h> 39 #include <setjmp.h> 40 #include <unistd.h> 41 42 #include "talk.h" 43 #include "talk_ctl.h" 44 45 #define STRING_LENGTH 158 46 47 /* 48 * There wasn't an invitation waiting, so send a request containing 49 * our sockt address to the remote talk daemon so it can invite 50 * him 51 */ 52 53 /* 54 * The msg.id's for the invitations 55 * on the local and remote machines. 56 * These are used to delete the 57 * invitations. 58 */ 59 int local_id, remote_id; 60 jmp_buf invitebuf; 61 62 void 63 invite_remote(void) 64 { 65 int new_sockt; 66 struct itimerval itimer; 67 CTL_RESPONSE response; 68 struct sockaddr rp; 69 socklen_t rplen = sizeof(struct sockaddr); 70 struct hostent *rphost; 71 char rname[STRING_LENGTH]; 72 73 itimer.it_value.tv_sec = RING_WAIT; 74 itimer.it_value.tv_usec = 0; 75 itimer.it_interval = itimer.it_value; 76 if (listen(sockt, 5) != 0) 77 quit("Error on attempt to listen for caller", 1); 78 #ifdef MSG_EOR 79 /* copy new style sockaddr to old, swap family (short in old) */ 80 msg.addr = *(struct osockaddr *)&my_addr; /* XXX new to old style*/ 81 msg.addr.sa_family = htons(my_addr.sin_family); 82 #else 83 msg.addr = *(struct sockaddr *)&my_addr; 84 #endif 85 msg.id_num = htonl(-1); /* an impossible id_num */ 86 invitation_waiting = 1; 87 announce_invite(); 88 /* 89 * Shut off the automatic messages for a while, 90 * so we can use the interrupt timer to resend the invitation. 91 * We no longer turn automatic messages back on to avoid a bonus 92 * message after we've connected; this is okay even though end_msgs() 93 * gets called again in main(). 94 */ 95 end_msgs(); 96 setitimer(ITIMER_REAL, &itimer, NULL); 97 message("Waiting for your party to respond"); 98 signal(SIGALRM, re_invite); 99 (void) setjmp(invitebuf); 100 while ((new_sockt = accept(sockt, &rp, &rplen)) == -1) { 101 if (errno == EINTR || errno == EWOULDBLOCK || 102 errno == ECONNABORTED) 103 continue; 104 quit("Unable to connect with your party", 1); 105 } 106 close(sockt); 107 sockt = new_sockt; 108 109 /* 110 * Have the daemons delete the invitations now that we 111 * have connected. 112 */ 113 msg.id_num = htonl(local_id); 114 ctl_transact(my_machine_addr, msg, DELETE, &response); 115 msg.id_num = htonl(remote_id); 116 ctl_transact(his_machine_addr, msg, DELETE, &response); 117 invitation_waiting = 0; 118 119 /* 120 * Check to see if the other guy is coming from the machine 121 * we expect. 122 */ 123 if (his_machine_addr.s_addr != 124 ((struct sockaddr_in *)&rp)->sin_addr.s_addr) { 125 rphost = gethostbyaddr((char *) &((struct sockaddr_in 126 *)&rp)->sin_addr, sizeof(struct in_addr), AF_INET); 127 if (rphost) 128 snprintf(rname, STRING_LENGTH, 129 "Answering talk request from %s@%s", msg.r_name, 130 rphost->h_name); 131 else 132 snprintf(rname, STRING_LENGTH, 133 "Answering talk request from %s@%s", msg.r_name, 134 inet_ntoa(((struct sockaddr_in *)&rp)->sin_addr)); 135 message(rname); 136 } 137 } 138 139 /* 140 * Routine called on interrupt to re-invite the callee 141 */ 142 void 143 re_invite(int dummy) 144 { 145 message("Ringing your party again"); 146 /* force a re-announce */ 147 msg.id_num = htonl(remote_id + 1); 148 announce_invite(); 149 longjmp(invitebuf, 1); 150 } 151 152 static char *answers[] = { 153 "answer #0", /* SUCCESS */ 154 "Your party is not logged on", /* NOT_HERE */ 155 "Target machine is too confused to talk to us", /* FAILED */ 156 "Target machine does not recognize us", /* MACHINE_UNKNOWN */ 157 "Your party is refusing messages", /* PERMISSION_REFUSED */ 158 "Target machine can not handle remote talk", /* UNKNOWN_REQUEST */ 159 "Target machine indicates protocol mismatch", /* BADVERSION */ 160 "Target machine indicates protocol botch (addr)",/* BADADDR */ 161 "Target machine indicates protocol botch (ctl_addr)",/* BADCTLADDR */ 162 }; 163 #define NANSWERS (sizeof (answers) / sizeof (answers[0])) 164 165 /* 166 * Transmit the invitation and process the response 167 */ 168 void 169 announce_invite(void) 170 { 171 CTL_RESPONSE response; 172 173 current_state = "Trying to connect to your party's talk daemon"; 174 ctl_transact(his_machine_addr, msg, ANNOUNCE, &response); 175 remote_id = response.id_num; 176 if (response.answer != SUCCESS) 177 quit(response.answer < NANSWERS ? answers[response.answer] : NULL, 0); 178 /* leave the actual invitation on my talk daemon */ 179 ctl_transact(my_machine_addr, msg, LEAVE_INVITE, &response); 180 local_id = response.id_num; 181 } 182 183 /* 184 * Tell the daemon to remove your invitation 185 */ 186 void 187 send_delete(void) 188 { 189 190 msg.type = DELETE; 191 /* 192 * This is just a extra clean up, so just send it 193 * and don't wait for an answer 194 */ 195 msg.id_num = htonl(remote_id); 196 daemon_addr.sin_addr = his_machine_addr; 197 if (sendto(ctl_sockt, &msg, sizeof (msg), 0, 198 (struct sockaddr *)&daemon_addr, 199 sizeof (daemon_addr)) != sizeof(msg)) 200 warn("send_delete (remote)"); 201 msg.id_num = htonl(local_id); 202 daemon_addr.sin_addr = my_machine_addr; 203 if (sendto(ctl_sockt, &msg, sizeof (msg), 0, 204 (struct sockaddr *)&daemon_addr, 205 sizeof (daemon_addr)) != sizeof (msg)) 206 warn("send_delete (local)"); 207 } 208