include/protocols/talkd.h

   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  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)talkd.h     8.1 (Berkeley) 6/2/93
  30  */
  31
  32 #ifndef _PROTOCOLS_TALKD_H
  33 #define _PROTOCOLS_TALKD_H 1
  34
  35 /*
  36  * This describes the protocol used by the talk server and clients.
  37  *
  38  * The talk server acts a repository of invitations, responding to
  39  * requests by clients wishing to rendezvous for the purpose of
  40  * holding a conversation.  In normal operation, a client, the caller,
  41  * initiates a rendezvous by sending a CTL_MSG to the server of
  42  * type LOOK_UP.  This causes the server to search its invitation
  43  * tables to check if an invitation currently exists for the caller
  44  * (to speak to the callee specified in the message).  If the lookup
  45  * fails, the caller then sends an ANNOUNCE message causing the server
  46  * to broadcast an announcement on the callee's login ports requesting
  47  * contact.  When the callee responds, the local server uses the
  48  * recorded invitation to respond with the appropriate rendezvous
  49  * address and the caller and callee client programs establish a
  50  * stream connection through which the conversation takes place.
  51  */
  52
  53 #include <sys/types.h>
  54 #include <sys/socket.h>
  55
  56 /*
  57  * Client->server request message format.
  58  */
  59 typedef struct {
  60         u_char  vers;           /* protocol version */
  61         u_char  type;           /* request type, see below */
  62         u_char  answer;         /* not used */
  63         u_char  pad;
  64         u_int32_t id_num;       /* message id */
  65         struct  osockaddr addr;         /* old (4.3) style */
  66         struct  osockaddr ctl_addr;     /* old (4.3) style */
  67         int32_t pid;            /* caller's process id */
  68 #define NAME_SIZE       12
  69         char    l_name[NAME_SIZE];/* caller's name */
  70         char    r_name[NAME_SIZE];/* callee's name */
  71 #define TTY_SIZE        16
  72         char    r_tty[TTY_SIZE];/* callee's tty name */
  73 } CTL_MSG;
  74
  75 /*
  76  * Server->client response message format.
  77  */
  78 typedef struct {
  79         u_char  vers;           /* protocol version */
  80         u_char  type;           /* type of request message, see below */
  81         u_char  answer;         /* response to request message, see below */
  82         u_char  pad;
  83         u_int32_t id_num;       /* message id */
  84         struct  osockaddr addr; /* address for establishing conversation */
  85 } CTL_RESPONSE;
  86
  87 #define TALK_VERSION    1               /* protocol version */
  88
  89 /* message type values */
  90 #define LEAVE_INVITE    0       /* leave invitation with server */
  91 #define LOOK_UP         1       /* check for invitation by callee */
  92 #define DELETE          2       /* delete invitation by caller */
  93 #define ANNOUNCE        3       /* announce invitation by caller */
  94
  95 /* answer values */
  96 #define SUCCESS         0       /* operation completed properly */
  97 #define NOT_HERE        1       /* callee not logged in */
  98 #define FAILED          2       /* operation failed for unexplained reason */
  99 #define MACHINE_UNKNOWN 3       /* caller's machine name unknown */
 100 #define PERMISSION_DENIED 4     /* callee's tty doesn't permit announce */
 101 #define UNKNOWN_REQUEST 5       /* request has invalid type value */
 102 #define BADVERSION      6       /* request has invalid protocol version */
 103 #define BADADDR         7       /* request has invalid addr value */
 104 #define BADCTLADDR      8       /* request has invalid ctl_addr value */
 105
 106 /*
 107  * Operational parameters.
 108  */
 109 #define MAX_LIFE        60      /* max time daemon saves invitations */
 110 /* RING_WAIT should be 10's of seconds less than MAX_LIFE */
 111 #define RING_WAIT       30      /* time to wait before resending invitation */
 112
 113 #endif /* protocols/talkd.h */