1: /* 2: * Copyright (c) 1983 Regents of the University of California. 3: * All rights reserved. The Berkeley software License Agreement 4: * specifies the terms and conditions for redistribution. 5: * 6: * @(#)talkd.h 5.2 (Berkeley) 3/13/86 7: */ 8: 9: #include <sys/types.h> 10: #include <sys/socket.h> 11: /* 12: * This describes the protocol used by the talk server and clients. 13: * 14: * The talk server acts a repository of invitations, responding to 15: * requests by clients wishing to rendezvous for the purpose of 16: * holding a conversation. In normal operation, a client, the caller, 17: * initiates a rendezvous by sending a CTL_MSG to the server of 18: * type LOOK_UP. This causes the server to search its invitation 19: * tables to check if an invitation currently exists for the caller 20: * (to speak to the callee specified in the message). If the lookup 21: * fails, the caller then sends an ANNOUNCE message causing the server 22: * to broadcast an announcement on the callee's login ports requesting 23: * contact. When the callee responds, the local server uses the 24: * recorded invitation to respond with the appropriate rendezvous 25: * address and the caller and callee client programs establish a 26: * stream connection through which the conversation takes place. 27: */ 28: 29: /* 30: * Client->server request message format. 31: */ 32: typedef struct { 33: u_char vers; /* protocol version */ 34: u_char type; /* request type, see below */ 35: u_char answer; /* not used */ 36: u_char pad; 37: u_long id_num; /* message id */ 38: struct sockaddr addr; 39: struct sockaddr ctl_addr; 40: long pid; /* caller's process id */ 41: #define NAME_SIZE 12 42: char l_name[NAME_SIZE];/* caller's name */ 43: char r_name[NAME_SIZE];/* callee's name */ 44: #define TTY_SIZE 16 45: char r_tty[TTY_SIZE];/* callee's tty name */ 46: } CTL_MSG; 47: 48: /* 49: * Server->client response message format. 50: */ 51: typedef struct { 52: u_char vers; /* protocol version */ 53: u_char type; /* type of request message, see below */ 54: u_char answer; /* respose to request message, see below */ 55: u_char pad; 56: u_long id_num; /* message id */ 57: struct sockaddr addr; /* address for establishing conversation */ 58: } CTL_RESPONSE; 59: 60: #define TALK_VERSION 1 /* protocol version */ 61: 62: /* message type values */ 63: #define LEAVE_INVITE 0 /* leave invitation with server */ 64: #define LOOK_UP 1 /* check for invitation by callee */ 65: #define DELETE 2 /* delete invitation by caller */ 66: #define ANNOUNCE 3 /* announce invitation by caller */ 67: 68: /* answer values */ 69: #define SUCCESS 0 /* operation completed properly */ 70: #define NOT_HERE 1 /* callee not logged in */ 71: #define FAILED 2 /* operation failed for unexplained reason */ 72: #define MACHINE_UNKNOWN 3 /* caller's machine name unknown */ 73: #define PERMISSION_DENIED 4 /* callee's tty doesn't permit announce */ 74: #define UNKNOWN_REQUEST 5 /* request has invalid type value */ 75: #define BADVERSION 6 /* request has invalid protocol version */ 76: #define BADADDR 7 /* request has invalid addr value */ 77: #define BADCTLADDR 8 /* request has invalid ctl_addr value */ 78: 79: /* 80: * Operational parameters. 81: */ 82: #define MAX_LIFE 60 /* max time daemon saves invitations */ 83: /* RING_WAIT should be 10's of seconds less than MAX_LIFE */ 84: #define RING_WAIT 30 /* time to wait before resending invitation */