/* $OpenBSD: announce.c,v 1.7 1998/07/03 14:33:38 deraadt Exp $ */ /* * Copyright (c) 1983 Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint /*static char sccsid[] = "from: @(#)announce.c 5.9 (Berkeley) 2/26/91";*/ static char rcsid[] = "$Id: announce.c,v 1.7 1998/07/03 14:33:38 deraadt Exp $"; #endif /* not lint */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "talkd.h" static void print_mesg __P((FILE *,CTL_MSG *,char *)); /* * Announce an invitation to talk. * * Because the tty driver insists on attaching a terminal-less * process to any terminal that it writes on, we must fork a child * to protect ourselves */ int announce(request, remote_machine) CTL_MSG *request; char *remote_machine; { int pid, val, status; if (pid = fork()) { /* we are the parent, so wait for the child */ if (pid == -1) /* the fork failed */ return (FAILED); do { val = wait(&status); if (val == -1) { if (errno == EINTR) continue; /* shouldn't happen */ syslog(LOG_WARNING, "announce: wait: %m"); return (FAILED); } } while (val != pid); if (status&0377 > 0) /* we were killed by some signal */ return (FAILED); /* Get the second byte, this is the exit/return code */ return ((status >> 8) & 0377); } /* we are the child, go and do it */ _exit(announce_proc(request, remote_machine)); } /* * See if the user is accepting messages. If so, announce that * a talk is requested. */ int announce_proc(request, remote_machine) CTL_MSG *request; char *remote_machine; { int pid, status; char full_tty[MAXPATHLEN]; FILE *tf; struct stat stbuf; (void)snprintf(full_tty, sizeof full_tty, "%s/%s", _PATH_DEV, request->r_tty); if (access(full_tty, 0) != 0) return (FAILED); if ((tf = fopen(full_tty, "w")) == NULL) return (PERMISSION_DENIED); /* * On first tty open, the server will have * it's pgrp set, so disconnect us from the * tty before we catch a signal. */ ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0); if (fstat(fileno(tf), &stbuf) < 0) return (PERMISSION_DENIED); if ((stbuf.st_mode&S_IWGRP) == 0) return (PERMISSION_DENIED); print_mesg(tf, request, remote_machine); fclose(tf); return (SUCCESS); } #define max(a,b) ( (a) > (b) ? (a) : (b) ) #define N_LINES 5 #define N_CHARS 120 /* * Build a block of characters containing the message. * It is sent blank filled and in a single block to * try to keep the message in one piece if the recipient * in in vi at the time */ static void print_mesg(tf, request, remote_machine) FILE *tf; CTL_MSG *request; char *remote_machine; { struct timeval clock; time_t clocktime; struct timezone zone; struct tm *localclock; char line_buf[N_LINES][N_CHARS]; int sizes[N_LINES]; char big_buf[N_LINES*N_CHARS]; char *bptr, *lptr, *vis_user; int i, j, max_size; i = 0; max_size = 0; gettimeofday(&clock, &zone); clocktime = clock.tv_sec; localclock = localtime(&clocktime); (void)snprintf(line_buf[i], N_CHARS, " "); sizes[i] = strlen(line_buf[i]); max_size = max(max_size, sizes[i]); i++; (void)snprintf(line_buf[i], N_CHARS, "Message from Talk_Daemon@%s at %d:%02d ...", hostname, localclock->tm_hour , localclock->tm_min ); sizes[i] = strlen(line_buf[i]); max_size = max(max_size, sizes[i]); i++; vis_user = (char *) malloc(strlen(request->l_name) * 4 + 1); strvis(vis_user, request->l_name, VIS_CSTYLE); (void)snprintf(line_buf[i], N_CHARS, "talk: connection requested by %s@%s.", vis_user, remote_machine); sizes[i] = strlen(line_buf[i]); max_size = max(max_size, sizes[i]); i++; (void)snprintf(line_buf[i], N_CHARS, "talk: respond with: talk %s@%s", vis_user, remote_machine); sizes[i] = strlen(line_buf[i]); max_size = max(max_size, sizes[i]); i++; (void)snprintf(line_buf[i], N_CHARS, " "); sizes[i] = strlen(line_buf[i]); max_size = max(max_size, sizes[i]); i++; bptr = big_buf; *bptr++ = '\007'; /* send something to wake them up */ *bptr++ = '\r'; /* add a \r in case of raw mode */ *bptr++ = '\n'; for (i = 0; i < N_LINES; i++) { /* copy the line into the big buffer */ lptr = line_buf[i]; while (*lptr != '\0') *(bptr++) = *(lptr++); /* pad out the rest of the lines with blanks */ for (j = sizes[i]; j < max_size + 2; j++) *(bptr++) = ' '; *(bptr++) = '\r'; /* add a \r in case of raw mode */ *(bptr++) = '\n'; } *bptr = '\0'; fprintf(tf, big_buf); fflush(tf); ioctl(fileno(tf), TIOCNOTTY, (struct sgttyb *) 0); }