1 /* 2 * Copyright (c) 1983 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 * 17 * @(#)talkd.h 5.4 (Berkeley) 08/16/89 18 */ 19 20 #include <sys/types.h> 21 #include <sys/socket.h> 22 /* 23 * This describes the protocol used by the talk server and clients. 24 * 25 * The talk server acts a repository of invitations, responding to 26 * requests by clients wishing to rendezvous for the purpose of 27 * holding a conversation. In normal operation, a client, the caller, 28 * initiates a rendezvous by sending a CTL_MSG to the server of 29 * type LOOK_UP. This causes the server to search its invitation 30 * tables to check if an invitation currently exists for the caller 31 * (to speak to the callee specified in the message). If the lookup 32 * fails, the caller then sends an ANNOUNCE message causing the server 33 * to broadcast an announcement on the callee's login ports requesting 34 * contact. When the callee responds, the local server uses the 35 * recorded invitation to respond with the appropriate rendezvous 36 * address and the caller and callee client programs establish a 37 * stream connection through which the conversation takes place. 38 */ 39 40 /* 41 * Client->server request message format. 42 */ 43 typedef struct { 44 u_char vers; /* protocol version */ 45 u_char type; /* request type, see below */ 46 u_char answer; /* not used */ 47 u_char pad; 48 u_long id_num; /* message id */ 49 struct osockaddr addr; /* old (4.3) style */ 50 struct osockaddr ctl_addr; /* old (4.3) style */ 51 long pid; /* caller's process id */ 52 #define NAME_SIZE 12 53 char l_name[NAME_SIZE];/* caller's name */ 54 char r_name[NAME_SIZE];/* callee's name */ 55 #define TTY_SIZE 16 56 char r_tty[TTY_SIZE];/* callee's tty name */ 57 } CTL_MSG; 58 59 /* 60 * Server->client response message format. 61 */ 62 typedef struct { 63 u_char vers; /* protocol version */ 64 u_char type; /* type of request message, see below */ 65 u_char answer; /* respose to request message, see below */ 66 u_char pad; 67 u_long id_num; /* message id */ 68 struct osockaddr addr; /* address for establishing conversation */ 69 } CTL_RESPONSE; 70 71 #define TALK_VERSION 1 /* protocol version */ 72 73 /* message type values */ 74 #define LEAVE_INVITE 0 /* leave invitation with server */ 75 #define LOOK_UP 1 /* check for invitation by callee */ 76 #define DELETE 2 /* delete invitation by caller */ 77 #define ANNOUNCE 3 /* announce invitation by caller */ 78 79 /* answer values */ 80 #define SUCCESS 0 /* operation completed properly */ 81 #define NOT_HERE 1 /* callee not logged in */ 82 #define FAILED 2 /* operation failed for unexplained reason */ 83 #define MACHINE_UNKNOWN 3 /* caller's machine name unknown */ 84 #define PERMISSION_DENIED 4 /* callee's tty doesn't permit announce */ 85 #define UNKNOWN_REQUEST 5 /* request has invalid type value */ 86 #define BADVERSION 6 /* request has invalid protocol version */ 87 #define BADADDR 7 /* request has invalid addr value */ 88 #define BADCTLADDR 8 /* request has invalid ctl_addr value */ 89 90 /* 91 * Operational parameters. 92 */ 93 #define MAX_LIFE 60 /* max time daemon saves invitations */ 94 /* RING_WAIT should be 10's of seconds less than MAX_LIFE */ 95 #define RING_WAIT 30 /* time to wait before resending invitation */ 96