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
  34 #ifndef lint
  35 #if 0
  36 static char sccsid[] = "@(#)announce.c  8.3 (Berkeley) 4/28/95";
  37 #endif
  38 static const char rcsid[] =
  39   "$FreeBSD$";
  40 #endif /* not lint */
  41
  42 #include <sys/types.h>
  43 #include <sys/uio.h>
  44 #include <sys/stat.h>
  45 #include <sys/time.h>
  46 #include <sys/wait.h>
  47 #include <sys/socket.h>
  48
  49 #include <protocols/talkd.h>
  50
  51 #include <errno.h>
  52 #include <paths.h>
  53 #include <stdio.h>
  54 #include <stdlib.h>
  55 #include <string.h>
  56 #include <syslog.h>
  57 #include <unistd.h>
  58 #include <vis.h>
  59
  60 #include "ttymsg.h"
  61 #include "extern.h"
  62
  63 extern char hostname[];
  64
  65 /*
  66  * Announce an invitation to talk.
  67  */
  68
  69 /*
  70  * See if the user is accepting messages. If so, announce that
  71  * a talk is requested.
  72  */
  73 int
  74 announce(CTL_MSG *request, const char *remote_machine)
  75 {
  76         char full_tty[32];
  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, 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 vi at the time
  95  */
  96 int
  97 print_mesg(const char *tty, CTL_MSG *request,
  98     const char *remote_machine)
  99 {
 100         struct timeval now;
 101         time_t clock_sec;
 102         struct timezone zone;
 103         struct tm *localclock;
 104         struct iovec iovec;
 105         char line_buf[N_LINES][N_CHARS];
 106         int sizes[N_LINES];
 107         char big_buf[N_LINES*N_CHARS];
 108         char *bptr, *lptr, *vis_user;
 109         int i, j, max_size;
 110
 111         i = 0;
 112         max_size = 0;
 113         gettimeofday(&now, &zone);
 114         clock_sec = now.tv_sec;
 115         localclock = localtime(&clock_sec);
 116         (void)snprintf(line_buf[i], N_CHARS, " ");
 117         sizes[i] = strlen(line_buf[i]);
 118         max_size = max(max_size, sizes[i]);
 119         i++;
 120         (void)snprintf(line_buf[i], N_CHARS,
 121                 "Message from Talk_Daemon@%s at %d:%02d on %d/%.2d/%.2d ...",
 122                 hostname, localclock->tm_hour , localclock->tm_min,
 123                 localclock->tm_year + 1900, localclock->tm_mon + 1,
 124                 localclock->tm_mday);
 125         sizes[i] = strlen(line_buf[i]);
 126         max_size = max(max_size, sizes[i]);
 127         i++;
 128
 129         vis_user = malloc(strlen(request->l_name) * 4 + 1);
 130         strvis(vis_user, request->l_name, VIS_CSTYLE);
 131         (void)snprintf(line_buf[i], N_CHARS,
 132             "talk: connection requested by %s@%s", vis_user, remote_machine);
 133         sizes[i] = strlen(line_buf[i]);
 134         max_size = max(max_size, sizes[i]);
 135         i++;
 136         (void)snprintf(line_buf[i], N_CHARS, "talk: respond with:  talk %s@%s",
 137             vis_user, remote_machine);
 138         sizes[i] = strlen(line_buf[i]);
 139         max_size = max(max_size, sizes[i]);
 140         i++;
 141         (void)snprintf(line_buf[i], N_CHARS, " ");
 142         sizes[i] = strlen(line_buf[i]);
 143         max_size = max(max_size, sizes[i]);
 144         i++;
 145         bptr = big_buf;
 146         *bptr++ = '\007'; /* send something to wake them up */
 147         *bptr++ = '\r'; /* add a \r in case of raw mode */
 148         *bptr++ = '\n';
 149         for (i = 0; i < N_LINES; i++) {
 150                 /* copy the line into the big buffer */
 151                 lptr = line_buf[i];
 152                 while (*lptr != '\0')
 153                         *(bptr++) = *(lptr++);
 154                 /* pad out the rest of the lines with blanks */
 155                 for (j = sizes[i]; j < max_size + 2; j++)
 156                         *(bptr++) = ' ';
 157                 *(bptr++) = '\r';       /* add a \r in case of raw mode */
 158                 *(bptr++) = '\n';
 159         }
 160         *bptr = '\0';
 161         iovec.iov_base = big_buf;
 162         iovec.iov_len = bptr - big_buf;
 163         /*
 164          * we choose a timeout of RING_WAIT-5 seconds so that we don't
 165          * stack up processes trying to write messages to a tty
 166          * that is permanently blocked.
 167          */
 168         if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
 169                 return (FAILED);
 170
 171         return (SUCCESS);
 172 }