FreeBSD-5.3/libexec/comsat/comsat.c
/*
* Copyright (c) 1980, 1993
* The 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 const char copyright[] =
"@(#) Copyright (c) 1980, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)comsat.c 8.1 (Berkeley) 6/4/93";
#endif
static const char rcsid[] =
"$FreeBSD: src/libexec/comsat/comsat.c,v 1.16 2002/07/09 02:16:49 johan Exp $";
#endif /* not lint */
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <netdb.h>
#include <paths.h>
#include <pwd.h>
#include <termios.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <utmp.h>
int debug = 0;
#define dsyslog if (debug) syslog
#define MAXIDLE 120
char hostname[MAXHOSTNAMELEN];
struct utmp *utmp = NULL;
time_t lastmsgtime;
int nutmp, uf;
void jkfprintf(FILE *, char[], char[], off_t);
void mailfor(char *);
void notify(struct utmp *, char[], off_t, int);
void onalrm(int);
void reapchildren(int);
int
main(int argc, char *argv[])
{
struct sockaddr_in from;
int cc;
int fromlen;
char msgbuf[256];
/* verify proper invocation */
fromlen = sizeof(from);
if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0)
err(1, "getsockname");
openlog("comsat", LOG_PID, LOG_DAEMON);
if (chdir(_PATH_MAILDIR)) {
syslog(LOG_ERR, "chdir: %s: %m", _PATH_MAILDIR);
(void) recv(0, msgbuf, sizeof(msgbuf) - 1, 0);
exit(1);
}
if ((uf = open(_PATH_UTMP, O_RDONLY, 0)) < 0) {
syslog(LOG_ERR, "open: %s: %m", _PATH_UTMP);
(void) recv(0, msgbuf, sizeof(msgbuf) - 1, 0);
exit(1);
}
(void)time(&lastmsgtime);
(void)gethostname(hostname, sizeof(hostname));
onalrm(0);
(void)signal(SIGALRM, onalrm);
(void)signal(SIGTTOU, SIG_IGN);
(void)signal(SIGCHLD, reapchildren);
for (;;) {
cc = recv(0, msgbuf, sizeof(msgbuf) - 1, 0);
if (cc <= 0) {
if (errno != EINTR)
sleep(1);
errno = 0;
continue;
}
if (!nutmp) /* no one has logged in yet */
continue;
sigblock(sigmask(SIGALRM));
msgbuf[cc] = '\0';
(void)time(&lastmsgtime);
mailfor(msgbuf);
sigsetmask(0L);
}
}
void
reapchildren(int signo)
{
while (wait3(NULL, WNOHANG, NULL) > 0);
}
void
onalrm(int signo)
{
static u_int utmpsize; /* last malloced size for utmp */
static u_int utmpmtime; /* last modification time for utmp */
struct stat statbf;
if (time(NULL) - lastmsgtime >= MAXIDLE)
exit(0);
(void)alarm((u_int)15);
(void)fstat(uf, &statbf);
if (statbf.st_mtime > utmpmtime) {
utmpmtime = statbf.st_mtime;
if (statbf.st_size > utmpsize) {
utmpsize = statbf.st_size + 10 * sizeof(struct utmp);
if ((utmp = realloc(utmp, utmpsize)) == NULL) {
syslog(LOG_ERR, "%s", strerror(errno));
exit(1);
}
}
(void)lseek(uf, (off_t)0, SEEK_SET);
nutmp = read(uf, utmp, (size_t)statbf.st_size)/sizeof(struct utmp);
}
}
void
mailfor(char *name)
{
struct utmp *utp = &utmp[nutmp];
char *cp;
char *file;
off_t offset;
int folder;
char buf[sizeof(_PATH_MAILDIR) + sizeof(utmp[0].ut_name) + 1];
char buf2[sizeof(_PATH_MAILDIR) + sizeof(utmp[0].ut_name) + 1];
if (!(cp = strchr(name, '@')))
return;
*cp = '\0';
offset = strtoll(cp + 1, NULL, 10);
if (!(cp = strchr(cp + 1, ':')))
file = name;
else
file = cp + 1;
sprintf(buf, "%s/%.*s", _PATH_MAILDIR, (int)sizeof(utmp[0].ut_name),
name);
if (*file != '/') {
sprintf(buf2, "%s/%.*s", _PATH_MAILDIR,
(int)sizeof(utmp[0].ut_name), file);
file = buf2;
}
folder = strcmp(buf, file);
while (--utp >= utmp)
if (!strncmp(utp->ut_name, name, sizeof(utmp[0].ut_name)))
notify(utp, file, offset, folder);
}
static char *cr;
void
notify(struct utmp *utp, char file[], off_t offset, int folder)
{
FILE *tp;
struct stat stb;
struct termios tio;
char tty[20], name[sizeof(utmp[0].ut_name) + 1];
(void)snprintf(tty, sizeof(tty), "%s%.*s",
_PATH_DEV, (int)sizeof(utp->ut_line), utp->ut_line);
if (strchr(tty + sizeof(_PATH_DEV) - 1, '/')) {
/* A slash is an attempt to break security... */
syslog(LOG_AUTH | LOG_NOTICE, "'/' in \"%s\"", tty);
return;
}
if (stat(tty, &stb) || !(stb.st_mode & (S_IXUSR | S_IXGRP))) {
dsyslog(LOG_DEBUG, "%s: wrong mode on %s", utp->ut_name, tty);
return;
}
dsyslog(LOG_DEBUG, "notify %s on %s\n", utp->ut_name, tty);
if (fork())
return;
(void)signal(SIGALRM, SIG_DFL);
(void)alarm((u_int)30);
if ((tp = fopen(tty, "w")) == NULL) {
dsyslog(LOG_ERR, "%s: %s", tty, strerror(errno));
_exit(1);
}
(void)tcgetattr(fileno(tp), &tio);
cr = ((tio.c_oflag & (OPOST|ONLCR)) == (OPOST|ONLCR)) ? "\n" : "\n\r";
(void)strncpy(name, utp->ut_name, sizeof(utp->ut_name));
name[sizeof(name) - 1] = '\0';
switch (stb.st_mode & (S_IXUSR | S_IXGRP)) {
case S_IXUSR:
case (S_IXUSR | S_IXGRP):
(void)fprintf(tp,
"%s\007New mail for %s@%.*s\007 has arrived%s%s%s:%s----%s",
cr, name, (int)sizeof(hostname), hostname,
folder ? cr : "", folder ? "to " : "", folder ? file : "",
cr, cr);
jkfprintf(tp, name, file, offset);
break;
case S_IXGRP:
(void)fprintf(tp, "\007");
(void)fflush(tp);
(void)sleep(1);
(void)fprintf(tp, "\007");
break;
default:
break;
}
(void)fclose(tp);
_exit(0);
}
void
jkfprintf(FILE *tp, char user[], char file[], off_t offset)
{
unsigned char *cp, ch;
FILE *fi;
int linecnt, charcnt, inheader;
struct passwd *p;
unsigned char line[BUFSIZ];
/* Set effective uid to user in case mail drop is on nfs */
if ((p = getpwnam(user)) != NULL)
(void) setuid(p->pw_uid);
if ((fi = fopen(file, "r")) == NULL)
return;
(void)fseeko(fi, offset, SEEK_CUR);
/*
* Print the first 7 lines or 560 characters of the new mail
* (whichever comes first). Skip header crap other than
* From, Subject, To, and Date.
*/
linecnt = 7;
charcnt = 560;
inheader = 1;
while (fgets(line, sizeof(line), fi) != NULL) {
if (inheader) {
if (line[0] == '\n') {
inheader = 0;
continue;
}
if (line[0] == ' ' || line[0] == '\t' ||
(strncmp(line, "From:", 5) &&
strncmp(line, "Subject:", 8)))
continue;
}
if (linecnt <= 0 || charcnt <= 0) {
(void)fprintf(tp, "...more...%s", cr);
(void)fclose(fi);
return;
}
/* strip weird stuff so can't trojan horse stupid terminals */
for (cp = line; (ch = *cp) && ch != '\n'; ++cp, --charcnt) {
/* disable upper controls and enable all other
8bit codes due to lack of locale knowledge
*/
if (((ch & 0x80) && ch < 0xA0) ||
(!(ch & 0x80) && !isprint(ch) &&
!isspace(ch) && ch != '\a' && ch != '\b')
) {
if (ch & 0x80) {
ch &= ~0x80;
(void)fputs("M-", tp);
}
if (iscntrl(ch)) {
ch ^= 0x40;
(void)fputc('^', tp);
}
}
(void)fputc(ch, tp);
}
(void)fputs(cr, tp);
--linecnt;
}
(void)fprintf(tp, "----%s\n", cr);
(void)fclose(fi);
}