libexec/talkd/announce.c

   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  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#)announce.c       8.3 (Berkeley) 4/28/95
  34  * $FreeBSD: src/libexec/talkd/announce.c,v 1.11.2.3 2001/10/18 12:30:42 des Exp $
  35  * $DragonFly: src/libexec/talkd/announce.c,v 1.3 2003/11/14 03:54:31 dillon Exp $
  36  */
  37
  38 #include <sys/types.h>
  39 #include <sys/uio.h>
  40 #include <sys/stat.h>
  41 #include <sys/time.h>
  42 #include <sys/wait.h>
  43 #include <sys/socket.h>
  44
  45 #include <protocols/talkd.h>
  46
  47 #include <errno.h>
  48 #include <paths.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <syslog.h>
  53 #include <unistd.h>
  54 #include <vis.h>
  55
  56 #include "ttymsg.h"
  57
  58 extern char hostname[];
  59
  60 int print_mesg (char *, FILE *, CTL_MSG *, char *);
  61
  62 /*
  63  * Announce an invitation to talk.
  64  */
  65
  66 /*
  67  * See if the user is accepting messages. If so, announce that
  68  * a talk is requested.
  69  */
  70 int
  71 announce(request, remote_machine)
  72         CTL_MSG *request;
  73         char *remote_machine;
  74 {
  75         char full_tty[32];
  76         FILE *tf;
  77         struct stat stbuf;
  78
  79         (void)snprintf(full_tty, sizeof(full_tty),
  80             "%s%s", _PATH_DEV, request->r_tty);
  81         if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
  82                 return (PERMISSION_DENIED);
  83         return (print_mesg(request->r_tty, tf, request, remote_machine));
  84 }
  85
  86 #define max(a,b) ( (a) > (b) ? (a) : (b) )
  87 #define N_LINES 5
  88 #define N_CHARS 256
  89
  90 /*
  91  * Build a block of characters containing the message.
  92  * It is sent blank filled and in a single block to
  93  * try to keep the message in one piece if the recipient
  94  * in in vi at the time
  95  */
  96 int
  97 print_mesg(tty, tf, request, remote_machine)
  98         char *tty;
  99         FILE *tf;
 100         CTL_MSG *request;
 101         char *remote_machine;
 102 {
 103         struct timeval clock;
 104         time_t clock_sec;
 105         struct timezone zone;
 106         struct tm *localtime();
 107         struct tm *localclock;
 108         struct iovec iovec;
 109         char line_buf[N_LINES][N_CHARS];
 110         int sizes[N_LINES];
 111         char big_buf[N_LINES*N_CHARS];
 112         char *bptr, *lptr, *vis_user;
 113         int i, j, max_size;
 114
 115         i = 0;
 116         max_size = 0;
 117         gettimeofday(&clock, &zone);
 118         clock_sec = clock.tv_sec;
 119         localclock = localtime(&clock_sec);
 120         (void)snprintf(line_buf[i], N_CHARS, " ");
 121         sizes[i] = strlen(line_buf[i]);
 122         max_size = max(max_size, sizes[i]);
 123         i++;
 124         (void)snprintf(line_buf[i], N_CHARS,
 125                 "Message from Talk_Daemon@%s at %d:%02d on %d/%.2d/%.2d ...",
 126                 hostname, localclock->tm_hour , localclock->tm_min,
 127                 localclock->tm_year + 1900, localclock->tm_mon + 1,
 128                 localclock->tm_mday);
 129         sizes[i] = strlen(line_buf[i]);
 130         max_size = max(max_size, sizes[i]);
 131         i++;
 132
 133         vis_user = malloc(strlen(request->l_name) * 4 + 1);
 134         strvis(vis_user, request->l_name, VIS_CSTYLE);
 135         (void)snprintf(line_buf[i], N_CHARS,
 136             "talk: connection requested by %s@%s", vis_user, remote_machine);
 137         sizes[i] = strlen(line_buf[i]);
 138         max_size = max(max_size, sizes[i]);
 139         i++;
 140         (void)snprintf(line_buf[i], N_CHARS, "talk: respond with:  talk %s@%s",
 141             vis_user, remote_machine);
 142         sizes[i] = strlen(line_buf[i]);
 143         max_size = max(max_size, sizes[i]);
 144         i++;
 145         (void)snprintf(line_buf[i], N_CHARS, " ");
 146         sizes[i] = strlen(line_buf[i]);
 147         max_size = max(max_size, sizes[i]);
 148         i++;
 149         bptr = big_buf;
 150         *bptr++ = '\007'; /* send something to wake them up */
 151         *bptr++ = '\r'; /* add a \r in case of raw mode */
 152         *bptr++ = '\n';
 153         for (i = 0; i < N_LINES; i++) {
 154                 /* copy the line into the big buffer */
 155                 lptr = line_buf[i];
 156                 while (*lptr != '\0')
 157                         *(bptr++) = *(lptr++);
 158                 /* pad out the rest of the lines with blanks */
 159                 for (j = sizes[i]; j < max_size + 2; j++)
 160                         *(bptr++) = ' ';
 161                 *(bptr++) = '\r';       /* add a \r in case of raw mode */
 162                 *(bptr++) = '\n';
 163         }
 164         *bptr = '\0';
 165         iovec.iov_base = big_buf;
 166         iovec.iov_len = bptr - big_buf;
 167         /*
 168          * we choose a timeout of RING_WAIT-5 seconds so that we don't
 169          * stack up processes trying to write messages to a tty
 170          * that is permanently blocked.
 171          */
 172         if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
 173                 return (FAILED);
 174
 175         return (SUCCESS);
 176 }