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 1.4 2008/08/23 22:26:56 swildner 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 *, 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         struct stat stbuf;
  77
  78         (void)snprintf(full_tty, sizeof(full_tty),
  79             "%s%s", _PATH_DEV, request->r_tty);
  80         if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
  81                 return (PERMISSION_DENIED);
  82         return (print_mesg(request->r_tty, request, remote_machine));
  83 }
  84
  85 #define max(a,b) ( (a) > (b) ? (a) : (b) )
  86 #define N_LINES 5
  87 #define N_CHARS 256
  88
  89 /*
  90  * Build a block of characters containing the message.
  91  * It is sent blank filled and in a single block to
  92  * try to keep the message in one piece if the recipient
  93  * in in vi at the time
  94  */
  95 int
  96 print_mesg(tty, request, remote_machine)
  97         char *tty;
  98         CTL_MSG *request;
  99         char *remote_machine;
 100 {
 101         struct timeval clock;
 102         time_t clock_sec;
 103         struct timezone zone;
 104         struct tm *localtime();
 105         struct tm *localclock;
 106         struct iovec iovec;
 107         char line_buf[N_LINES][N_CHARS];
 108         int sizes[N_LINES];
 109         char big_buf[N_LINES*N_CHARS];
 110         char *bptr, *lptr, *vis_user;
 111         int i, j, max_size;
 112
 113         i = 0;
 114         max_size = 0;
 115         gettimeofday(&clock, &zone);
 116         clock_sec = clock.tv_sec;
 117         localclock = localtime(&clock_sec);
 118         (void)snprintf(line_buf[i], N_CHARS, " ");
 119         sizes[i] = strlen(line_buf[i]);
 120         max_size = max(max_size, sizes[i]);
 121         i++;
 122         (void)snprintf(line_buf[i], N_CHARS,
 123                 "Message from Talk_Daemon@%s at %d:%02d on %d/%.2d/%.2d ...",
 124                 hostname, localclock->tm_hour , localclock->tm_min,
 125                 localclock->tm_year + 1900, localclock->tm_mon + 1,
 126                 localclock->tm_mday);
 127         sizes[i] = strlen(line_buf[i]);
 128         max_size = max(max_size, sizes[i]);
 129         i++;
 130
 131         vis_user = malloc(strlen(request->l_name) * 4 + 1);
 132         strvis(vis_user, request->l_name, VIS_CSTYLE);
 133         (void)snprintf(line_buf[i], N_CHARS,
 134             "talk: connection requested by %s@%s", vis_user, remote_machine);
 135         sizes[i] = strlen(line_buf[i]);
 136         max_size = max(max_size, sizes[i]);
 137         i++;
 138         (void)snprintf(line_buf[i], N_CHARS, "talk: respond with:  talk %s@%s",
 139             vis_user, remote_machine);
 140         sizes[i] = strlen(line_buf[i]);
 141         max_size = max(max_size, sizes[i]);
 142         i++;
 143         (void)snprintf(line_buf[i], N_CHARS, " ");
 144         sizes[i] = strlen(line_buf[i]);
 145         max_size = max(max_size, sizes[i]);
 146         bptr = big_buf;
 147         *bptr++ = '\007'; /* send something to wake them up */
 148         *bptr++ = '\r'; /* add a \r in case of raw mode */
 149         *bptr++ = '\n';
 150         for (i = 0; i < N_LINES; i++) {
 151                 /* copy the line into the big buffer */
 152                 lptr = line_buf[i];
 153                 while (*lptr != '\0')
 154                         *(bptr++) = *(lptr++);
 155                 /* pad out the rest of the lines with blanks */
 156                 for (j = sizes[i]; j < max_size + 2; j++)
 157                         *(bptr++) = ' ';
 158                 *(bptr++) = '\r';       /* add a \r in case of raw mode */
 159                 *(bptr++) = '\n';
 160         }
 161         *bptr = '\0';
 162         iovec.iov_base = big_buf;
 163         iovec.iov_len = bptr - big_buf;
 164         /*
 165          * we choose a timeout of RING_WAIT-5 seconds so that we don't
 166          * stack up processes trying to write messages to a tty
 167          * that is permanently blocked.
 168          */
 169         if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
 170                 return (FAILED);
 171
 172         return (SUCCESS);
 173 }