* Simple telnet server
* Bjorn Wesen, Axis Communications AB (bjornw@axis.com)
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
* ---------------------------------------------------------------------------
* (C) Copyright 2000, Axis Communications AB, LUND, SWEDEN
* Vladimir Oleynik <dzo@simtreas.ru> 2001
* Set process group corrections, initial busybox port
*/
+
+//usage:#define telnetd_trivial_usage
+//usage: "[OPTIONS]"
+//usage:#define telnetd_full_usage "\n\n"
+//usage: "Handle incoming telnet connections"
+//usage: IF_NOT_FEATURE_TELNETD_STANDALONE(" via inetd") "\n"
+//usage: "\n -l LOGIN Exec LOGIN on connect"
+//usage: "\n -f ISSUE_FILE Display ISSUE_FILE instead of /etc/issue"
+//usage: "\n -K Close connection as soon as login exits"
+//usage: "\n (normally wait until all programs close slave pty)"
+//usage: IF_FEATURE_TELNETD_STANDALONE(
+//usage: "\n -p PORT Port to listen on"
+//usage: "\n -b ADDR[:PORT] Address to bind to"
+//usage: "\n -F Run in foreground"
+//usage: "\n -i Inetd mode"
+//usage: IF_FEATURE_TELNETD_INETD_WAIT(
+//usage: "\n -w SEC Inetd 'wait' mode, linger time SEC"
+//usage: "\n -S Log to syslog (implied by -i or without -F and -w)"
+//usage: )
+//usage: )
+
#define DEBUG 0
#include "libbb.h"
#endif
#include <arpa/telnet.h>
-#if ENABLE_FEATURE_UTMP
-# include <utmp.h> /* LOGIN_PROCESS */
-#endif
-
struct tsession {
struct tsession *next;
/* We map \r\n ==> \r for pragmatic reasons.
* Many client implementations send \r\n when
* the user hits the CarriageReturn key.
+ * See RFC 1123 3.3.1 Telnet End-of-Line Convention.
*/
if (c == '\r' && ptr < end && (*ptr == '\n' || *ptr == '\0'))
ptr++;
if (ptr[1] == SB && ptr[2] == TELOPT_NAWS) {
struct winsize ws;
if ((ptr+8) >= end)
- break; /* incomplete, can't process */
+ break; /* incomplete, can't process */
ws.ws_col = (ptr[3] << 8) | ptr[4];
ws.ws_row = (ptr[5] << 8) | ptr[6];
ioctl(ts->ptyfd, TIOCSWINSZ, (char *)&ws);
IF_FEATURE_TELNETD_STANDALONE(int sock)
IF_NOT_FEATURE_TELNETD_STANDALONE(void)
) {
+#if !ENABLE_FEATURE_TELNETD_STANDALONE
+ enum { sock = 0 };
+#endif
const char *login_argv[2];
struct termios termbuf;
int fd, pid;
ndelay_on(fd);
close_on_exec_on(fd);
-#if ENABLE_FEATURE_TELNETD_STANDALONE
/* SO_KEEPALIVE by popular demand */
setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
+#if ENABLE_FEATURE_TELNETD_STANDALONE
ts->sockfd_read = sock;
ndelay_on(sock);
if (sock == 0) { /* We are called with fd 0 - we are in inetd mode */
if (sock > G.maxfd)
G.maxfd = sock;
#else
- /* SO_KEEPALIVE by popular demand */
- setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
/* ts->sockfd_read = 0; - done by xzalloc */
ts->sockfd_write = 1;
ndelay_on(0);
static const char iacs_to_send[] ALIGN1 = {
IAC, DO, TELOPT_ECHO,
IAC, DO, TELOPT_NAWS,
- /* This requires telnetd.ctrlSQ.patch (incomplete) */
- /* IAC, DO, TELOPT_LFLOW, */
+ /* This requires telnetd.ctrlSQ.patch (incomplete) */
+ /*IAC, DO, TELOPT_LFLOW,*/
IAC, WILL, TELOPT_ECHO,
IAC, WILL, TELOPT_SGA
};
/* Restore default signal handling ASAP */
bb_signals((1 << SIGCHLD) + (1 << SIGPIPE), SIG_DFL);
+ pid = getpid();
+
+ if (ENABLE_FEATURE_UTMP) {
+ len_and_sockaddr *lsa = get_peer_lsa(sock);
+ char *hostname = NULL;
+ if (lsa) {
+ hostname = xmalloc_sockaddr2dotted(&lsa->u.sa);
+ free(lsa);
+ }
+ write_new_utmp(pid, LOGIN_PROCESS, tty_name, /*username:*/ "LOGIN", hostname);
+ free(hostname);
+ }
+
/* Make new session and process group */
setsid();
xopen(tty_name, O_RDWR); /* becomes our ctty */
xdup2(0, 1);
xdup2(0, 2);
- pid = getpid();
tcsetpgrp(0, pid); /* switch this tty's process group to us */
-//TODO: fetch remote addr via getpeername (see ftpd.c)
- write_new_utmp(pid, LOGIN_PROCESS, tty_name, /*username:*/ "LOGIN", /*hostname:*/ NULL);
-
/* The pseudo-terminal allocated to the client is configured to operate
* in cooked mode, and with XTABS CRMOD enabled (see tty(4)) */
tcgetattr(0, &termbuf);