/*
* Copyright (c) 2003, Adam Dunkels.
* 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. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include <sys/types.h>
#include <stdlib.h>
#include <string.h>
#include <net/uip/uip.h>
#include "telnetd.h"
#include "shell.h"
#define ISO_nl 0x0a
#define ISO_cr 0x0d
#define STATE_NORMAL 0
#define STATE_IAC 1
#define STATE_WILL 2
#define STATE_WONT 3
#define STATE_DO 4
#define STATE_DONT 5
#define STATE_CLOSE 6
static struct telnetd_state s;
#define TELNET_IAC 255
#define TELNET_WILL 251
#define TELNET_WONT 252
#define TELNET_DO 253
#define TELNET_DONT 254
/*---------------------------------------------------------------------------*/
void
shell_quit(char *str)
{
s.state = STATE_CLOSE;
}
/*---------------------------------------------------------------------------*/
static void
sendline(char *line)
{
static unsigned int i;
for(i = 0; i < TELNETD_CONF_NUMLINES; ++i) {
if(s.lines[i] == NULL) {
s.lines[i] = line;
break;
}
}
if(i == TELNETD_CONF_NUMLINES) {
free(line);
}
}
/*---------------------------------------------------------------------------*/
void
shell_prompt(char *str)
{
char *line;
line = (char*)malloc(TELNETD_CONF_LINELEN);
if(line != NULL) {
strncpy(line, str, TELNETD_CONF_LINELEN);
/* petsciiconv_toascii(line, TELNETD_CONF_LINELEN);*/
sendline(line);
}
}
/*---------------------------------------------------------------------------*/
void
shell_output(char *str1, char *str2)
{
static unsigned len;
char *line;
line = (char*)malloc(TELNETD_CONF_LINELEN);
if(line != NULL) {
len = strlen(str1);
strncpy(line, str1, TELNETD_CONF_LINELEN);
if(len < TELNETD_CONF_LINELEN) {
strncpy(line + len, str2, TELNETD_CONF_LINELEN - len);
}
len = strlen(line);
if(len < TELNETD_CONF_LINELEN - 2) {
line[len] = ISO_cr;
line[len+1] = ISO_nl;
line[len+2] = 0;
}
/* petsciiconv_toascii(line, TELNETD_CONF_LINELEN);*/
sendline(line);
}
}
/*---------------------------------------------------------------------------*/
void
telnetd_init(void)
{
uip_listen(HTONS(23));
shell_init();
}
/*---------------------------------------------------------------------------*/
static void
acked(void)
{
static unsigned int i;
while(s.numsent > 0) {
free(s.lines[0]);
for(i = 1; i < TELNETD_CONF_NUMLINES; ++i) {
s.lines[i - 1] = s.lines[i];
}
s.lines[TELNETD_CONF_NUMLINES - 1] = NULL;
--s.numsent;
}
}
/*---------------------------------------------------------------------------*/
static void
senddata(void)
{
static char *bufptr, *lineptr;
static int buflen, linelen;
bufptr = uip_appdata;
buflen = 0;
for(s.numsent = 0; s.numsent < TELNETD_CONF_NUMLINES &&
s.lines[s.numsent] != NULL ; ++s.numsent) {
lineptr = s.lines[s.numsent];
linelen = strlen(lineptr);
if(linelen > TELNETD_CONF_LINELEN) {
linelen = TELNETD_CONF_LINELEN;
}
if(buflen + linelen < uip_mss()) {
memcpy(bufptr, lineptr, linelen);
bufptr += linelen;
buflen += linelen;
} else {
break;
}
}
uip_send(uip_appdata, buflen);
}
/*---------------------------------------------------------------------------*/
static void
closed(void)
{
static unsigned int i;
for(i = 0; i < TELNETD_CONF_NUMLINES; ++i) {
if(s.lines[i] != NULL) {
free(s.lines[i]);
}
}
}
/*---------------------------------------------------------------------------*/
static void
get_char(uint8 c)
{
if(c == ISO_cr) {
return;
}
s.buf[(int)s.bufptr] = c;
if(s.buf[(int)s.bufptr] == ISO_nl ||
s.bufptr == sizeof(s.buf) - 1) {
if(s.bufptr > 0) {
s.buf[(int)s.bufptr] = 0;
/* petsciiconv_topetscii(s.buf, TELNETD_CONF_LINELEN);*/
}
shell_input(s.buf);
s.bufptr = 0;
} else {
++s.bufptr;
}
}
/*---------------------------------------------------------------------------*/
static void
sendopt(uint8 option, uint8 value)
{
char *line;
line = (char*)malloc(TELNETD_CONF_LINELEN);
if(line != NULL) {
line[0] = TELNET_IAC;
line[1] = option;
line[2] = value;
line[3] = 0;
sendline(line);
}
}
/*---------------------------------------------------------------------------*/
static void
newdata(void)
{
uint16 len;
uint8 c;
char *dataptr;
len = uip_datalen();
dataptr = (char *)uip_appdata;
while(len > 0 && s.bufptr < sizeof(s.buf)) {
c = *dataptr;
++dataptr;
--len;
switch(s.state) {
case STATE_IAC:
if(c == TELNET_IAC) {
get_char(c);
s.state = STATE_NORMAL;
} else {
switch(c) {
case TELNET_WILL:
s.state = STATE_WILL;
break;
case TELNET_WONT:
s.state = STATE_WONT;
break;
case TELNET_DO:
s.state = STATE_DO;
break;
case TELNET_DONT:
s.state = STATE_DONT;
break;
default:
s.state = STATE_NORMAL;
break;
}
}
break;
case STATE_WILL:
/* Reply with a DONT */
sendopt(TELNET_DONT, c);
s.state = STATE_NORMAL;
break;
case STATE_WONT:
/* Reply with a DONT */
sendopt(TELNET_DONT, c);
s.state = STATE_NORMAL;
break;
case STATE_DO:
/* Reply with a WONT */
sendopt(TELNET_WONT, c);
s.state = STATE_NORMAL;
break;
case STATE_DONT:
/* Reply with a WONT */
sendopt(TELNET_WONT, c);
s.state = STATE_NORMAL;
break;
case STATE_NORMAL:
if(c == TELNET_IAC) {
s.state = STATE_IAC;
} else {
get_char(c);
}
break;
}
}
}
/* This function is called by the UIP interrupt handling logic whenevent an
* event of interest occurs.
*/
void uip_interrupt_event(void)
{
#warning OBSOLETE -- needs to be redesigned
static unsigned int i;
if(uip_connected()) {
/* tcp_markconn(uip_conn, &s);*/
for(i = 0; i < TELNETD_CONF_NUMLINES; ++i) {
s.lines[i] = NULL;
}
s.bufptr = 0;
s.state = STATE_NORMAL;
shell_start();
}
if(s.state == STATE_CLOSE) {
s.state = STATE_NORMAL;
uip_close();
return;
}
if(uip_closed() ||
uip_aborted() ||
uip_timedout()) {
closed();
}
if(uip_acked()) {
acked();
}
if(uip_newdata()) {
newdata();
}
if(uip_rexmit() ||
uip_newdata() ||
uip_acked() ||
uip_connected() ||
uip_poll()) {
senddata();
}
}
/*---------------------------------------------------------------------------*/
