OpenBSD-4.6/libexec/uucpd/uucpd.c
/* $OpenBSD: uucpd.c,v 1.31 2006/04/02 00:48:55 deraadt Exp $ */
/*
* Copyright (c) 1985 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rick Adams.
*
* 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. 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
char copyright[] =
"@(#) Copyright (c) 1985 The Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */
#ifndef lint
/*static char sccsid[] = "from: @(#)uucpd.c 5.10 (Berkeley) 2/26/91";*/
static char rcsid[] = "$OpenBSD: uucpd.c,v 1.31 2006/04/02 00:48:55 deraadt Exp $";
#endif /* not lint */
/*
* 4.2BSD TCP/IP server for uucico
* uucico's TCP channel causes this server to be run at the remote end.
*/
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <signal.h>
#include <fcntl.h>
#include <time.h>
#include <pwd.h>
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <login_cap.h>
#include <utmp.h>
#include <fcntl.h>
#include "pathnames.h"
void doit(struct sockaddr *);
int readline(char *, int n);
void dologout(void);
void dologin(struct passwd *, struct sockaddr *);
struct sockaddr_storage hisctladdr;
socklen_t hisaddrlen = sizeof hisctladdr;
pid_t mypid;
char Username[64], Loginname[64];
char *nenv[] = {
Username,
Loginname,
NULL,
};
extern char **environ;
char utline[UT_LINESIZE+1];
int
main(int argc, char *argv[])
{
#ifndef BSDINETD
int s, tcp_socket;
struct servent *sp;
#endif /* !BSDINETD */
pid_t childpid;
environ = nenv;
#ifdef BSDINETD
close(1); close(2);
dup(0); dup(0);
hisaddrlen = sizeof (hisctladdr);
if (getpeername(0, (struct sockaddr *)&hisctladdr, &hisaddrlen) < 0) {
fprintf(stderr, "%s: ", argv[0]);
perror("getpeername");
_exit(1);
}
if ((childpid = fork()) == 0)
doit((struct sockaddr *)&hisctladdr);
snprintf(utline, sizeof(utline), "uucp%.4ld", (long)childpid);
dologout();
exit(1);
#else /* !BSDINETD */
sp = getservbyname("uucp", "tcp");
if (sp == NULL){
perror("uucpd: getservbyname");
exit(1);
}
if (fork())
exit(0);
snprintf(utline, sizeof(utline), "uucp%.4ld", (long)childpid);
if ((s = open(_PATH_TTY, 2)) >= 0){
ioctl(s, TIOCNOTTY, (char *)0);
close(s);
}
bzero((char *)&myctladdr, sizeof (myctladdr));
myctladdr.sin_len = sizeof(struct sockaddr_in);
myctladdr.sin_family = AF_INET;
myctladdr.sin_port = sp->s_port;
tcp_socket = socket(AF_INET, SOCK_STREAM, 0);
if (tcp_socket < 0) {
perror("uucpd: socket");
exit(1);
}
if (bind(tcp_socket, (char *)&myctladdr, sizeof (myctladdr)) < 0) {
perror("uucpd: bind");
exit(1);
}
listen(tcp_socket, 3); /* at most 3 simultaneuos uucp connections */
signal(SIGCHLD, dologout);
for(;;) {
s = accept(tcp_socket, &hisctladdr, &hisaddrlen);
if (s < 0){
if (errno == EINTR)
continue;
perror("uucpd: accept");
exit(1);
}
if (fork() == 0) {
close(0); close(1); close(2);
dup(s); dup(s); dup(s);
close(tcp_socket); close(s);
doit(&hisctladdr);
exit(1);
}
close(s);
}
#endif /* !BSDINETD */
}
void
doit(struct sockaddr *sa)
{
char user[64], passwd[64];
char *xpasswd;
struct passwd *pw;
alarm(60);
do {
printf("login: ");
fflush(stdout);
if (readline(user, sizeof user) < 0) {
fprintf(stderr, "user read\n");
return;
}
} while (user[0] == '\0');
user[MAXLOGNAME] = '\0';
pw = getpwnam(user);
if (pw == NULL) {
printf("Password: ");
fflush(stdout);
if (readline(passwd, sizeof passwd) < 0) {
fprintf(stderr, "passwd read\n");
return;
}
fprintf(stderr, "Login incorrect.");
return;
}
if (pw->pw_passwd && *pw->pw_passwd != '\0') {
printf("Password: ");
fflush(stdout);
if (readline(passwd, sizeof passwd) < 0) {
fprintf(stderr, "passwd read\n");
return;
}
xpasswd = crypt(passwd, pw->pw_passwd);
if (strcmp(xpasswd, pw->pw_passwd)) {
fprintf(stderr, "Login incorrect.");
return;
}
}
if (strcmp(pw->pw_shell, _PATH_UUCICO)) {
fprintf(stderr, "Login incorrect.\n");
return;
}
alarm(0);
(void) snprintf(Username, sizeof(Username), "USER=%s", user);
(void) snprintf(Loginname, sizeof(Loginname), "LOGNAME=%s", user);
dologin(pw, sa);
if (setusercontext(0, pw, pw->pw_uid, LOGIN_SETALL) != 0) {
perror("unable to set user context");
return;
}
chdir(pw->pw_dir);
execl(_PATH_UUCICO, "uucico", (char *)NULL);
perror("uucico server: execl");
}
int
readline(char *p, int n)
{
char c;
while (n-- > 0) {
if (read(STDIN_FILENO, &c, 1) <= 0)
return(-1);
c &= 0177;
if (c == '\r') {
*p = '\0';
return(0);
}
if (c != '\n')
*p++ = c;
}
return(-1);
}
#define SCPYN(a, b) strncpy(a, b, sizeof (a))
struct utmp utmp;
void
dologout(void)
{
int save_errno = errno;
int status, wtmp;
pid_t pid;
#ifdef BSDINETD
while ((pid=wait(&status)) > 0) {
#else /* !BSDINETD */
while ((pid=wait3(&status, WNOHANG, 0)) > 0) {
#endif /* !BSDINETD */
wtmp = open(_PATH_WTMP, O_WRONLY|O_APPEND);
if (wtmp >= 0) {
SCPYN(utmp.ut_line, utline);
SCPYN(utmp.ut_name, "");
SCPYN(utmp.ut_host, "");
(void) time(&utmp.ut_time);
(void) write(wtmp, (char *)&utmp, sizeof (utmp));
(void) close(wtmp);
}
}
errno = save_errno;
}
/*
* Record login in wtmp file.
*/
void
dologin(struct passwd *pw, struct sockaddr *sa)
{
char line[32];
char hbuf[NI_MAXHOST];
int wtmp, f;
if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0, 0))
(void)strlcpy(hbuf, "?", sizeof(hbuf));
wtmp = open(_PATH_WTMP, O_WRONLY|O_APPEND);
if (wtmp >= 0) {
/* hack, but must be unique and no tty line */
(void) snprintf(line, sizeof line, "uucp%.4ld", (long)getpid());
SCPYN(utmp.ut_line, line);
SCPYN(utmp.ut_name, pw->pw_name);
SCPYN(utmp.ut_host, hbuf);
time(&utmp.ut_time);
(void) write(wtmp, (char *)&utmp, sizeof (utmp));
(void) close(wtmp);
}
if ((f = open(_PATH_LASTLOG, O_RDWR)) >= 0) {
struct lastlog ll;
time(&ll.ll_time);
lseek(f, pw->pw_uid * sizeof(struct lastlog), SEEK_SET);
SCPYN(ll.ll_line, hbuf);
SCPYN(ll.ll_host, hbuf);
(void) write(f, (char *) &ll, sizeof ll);
(void) close(f);
}
}