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/*
* Rlogin backend.
*/
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <ctype.h>
#include "putty.h"
#ifndef FALSE
#define FALSE 0
#endif
#ifndef TRUE
#define TRUE 1
#endif
#define RLOGIN_MAX_BACKLOG 4096
typedef struct rlogin_tag {
const struct plug_function_table *fn;
/* the above field _must_ be first in the structure */
Socket s;
int closed_on_socket_error;
int bufsize;
int firstbyte;
int cansize;
int term_width, term_height;
void *frontend;
Conf *conf;
/* In case we need to read a username from the terminal before starting */
prompts_t *prompt;
} *Rlogin;
static void rlogin_size(void *handle, int width, int height);
static void c_write(Rlogin rlogin, char *buf, int len)
{
int backlog = from_backend(rlogin->frontend, 0, buf, len);
sk_set_frozen(rlogin->s, backlog > RLOGIN_MAX_BACKLOG);
}
static void rlogin_log(Plug plug, int type, SockAddr addr, int port,
const char *error_msg, int error_code)
{
Rlogin rlogin = (Rlogin) plug;
backend_socket_log(rlogin->frontend, type, addr, port,
error_msg, error_code,
rlogin->conf, !rlogin->firstbyte);
}
static int rlogin_closing(Plug plug, const char *error_msg, int error_code,
int calling_back)
{
Rlogin rlogin = (Rlogin) plug;
/*
* We don't implement independent EOF in each direction for Telnet
* connections; as soon as we get word that the remote side has
* sent us EOF, we wind up the whole connection.
*/
if (rlogin->s) {
sk_close(rlogin->s);
rlogin->s = NULL;
if (error_msg)
rlogin->closed_on_socket_error = TRUE;
notify_remote_exit(rlogin->frontend);
}
if (error_msg) {
/* A socket error has occurred. */
logevent(rlogin->frontend, error_msg);
connection_fatal(rlogin->frontend, "%s", error_msg);
} /* Otherwise, the remote side closed the connection normally. */
return 0;
}
static int rlogin_receive(Plug plug, int urgent, char *data, int len)
{
Rlogin rlogin = (Rlogin) plug;
if (urgent == 2) {
char c;
c = *data++;
len--;
if (c == '\x80') {
rlogin->cansize = 1;
rlogin_size(rlogin, rlogin->term_width, rlogin->term_height);
}
/*
* We should flush everything (aka Telnet SYNCH) if we see
* 0x02, and we should turn off and on _local_ flow control
* on 0x10 and 0x20 respectively. I'm not convinced it's
* worth it...
*/
} else {
/*
* Main rlogin protocol. This is really simple: the first
* byte is expected to be NULL and is ignored, and the rest
* is printed.
*/
if (rlogin->firstbyte) {
if (data[0] == '\0') {
data++;
len--;
}
rlogin->firstbyte = 0;
}
if (len > 0)
c_write(rlogin, data, len);
}
return 1;
}
static void rlogin_sent(Plug plug, int bufsize)
{
Rlogin rlogin = (Rlogin) plug;
rlogin->bufsize = bufsize;
}
static void rlogin_startup(Rlogin rlogin, const char *ruser)
{
char z = 0;
char *p;
sk_write(rlogin->s, &z, 1);
p = conf_get_str(rlogin->conf, CONF_localusername);
sk_write(rlogin->s, p, strlen(p));
sk_write(rlogin->s, &z, 1);
sk_write(rlogin->s, ruser, strlen(ruser));
sk_write(rlogin->s, &z, 1);
p = conf_get_str(rlogin->conf, CONF_termtype);
sk_write(rlogin->s, p, strlen(p));
sk_write(rlogin->s, "/", 1);
p = conf_get_str(rlogin->conf, CONF_termspeed);
sk_write(rlogin->s, p, strspn(p, "0123456789"));
rlogin->bufsize = sk_write(rlogin->s, &z, 1);
rlogin->prompt = NULL;
}
/*
* Called to set up the rlogin connection.
*
* Returns an error message, or NULL on success.
*
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
static const char *rlogin_init(void *frontend_handle, void **backend_handle,
Conf *conf,
const char *host, int port, char **realhost,
int nodelay, int keepalive)
{
static const struct plug_function_table fn_table = {
rlogin_log,
rlogin_closing,
rlogin_receive,
rlogin_sent,
NULL
};
SockAddr addr;
const char *err;
Rlogin rlogin;
char *ruser;
int addressfamily;
char *loghost;
rlogin = snew(struct rlogin_tag);
rlogin->fn = &fn_table;
rlogin->s = NULL;
rlogin->closed_on_socket_error = FALSE;
rlogin->frontend = frontend_handle;
rlogin->term_width = conf_get_int(conf, CONF_width);
rlogin->term_height = conf_get_int(conf, CONF_height);
rlogin->firstbyte = 1;
rlogin->cansize = 0;
rlogin->prompt = NULL;
rlogin->conf = conf_copy(conf);
*backend_handle = rlogin;
addressfamily = conf_get_int(conf, CONF_addressfamily);
/*
* Try to find host.
*/
addr = name_lookup(host, port, realhost, conf, addressfamily,
rlogin->frontend, "rlogin connection");
if ((err = sk_addr_error(addr)) != NULL) {
sk_addr_free(addr);
return err;
}
if (port < 0)
port = 513; /* default rlogin port */
/*
* Open socket.
*/
rlogin->s = new_connection(addr, *realhost, port, 1, 0,
nodelay, keepalive, (Plug) rlogin, conf);
if ((err = sk_socket_error(rlogin->s)) != NULL)
return err;
loghost = conf_get_str(conf, CONF_loghost);
if (*loghost) {
char *colon;
sfree(*realhost);
*realhost = dupstr(loghost);
colon = host_strrchr(*realhost, ':');
if (colon)
*colon++ = '\0';
}
/*
* Send local username, remote username, terminal type and
* terminal speed - unless we don't have the remote username yet,
* in which case we prompt for it and may end up deferring doing
* anything else until the local prompt mechanism returns.
*/
if ((ruser = get_remote_username(conf)) != NULL) {
rlogin_startup(rlogin, ruser);
sfree(ruser);
} else {
int ret;
rlogin->prompt = new_prompts(rlogin->frontend);
rlogin->prompt->to_server = TRUE;
rlogin->prompt->name = dupstr("Rlogin login name");
add_prompt(rlogin->prompt, dupstr("rlogin username: "), TRUE);
ret = get_userpass_input(rlogin->prompt, NULL, 0);
if (ret >= 0) {
rlogin_startup(rlogin, rlogin->prompt->prompts[0]->result);
}
}
return NULL;
}
static void rlogin_free(void *handle)
{
Rlogin rlogin = (Rlogin) handle;
if (rlogin->prompt)
free_prompts(rlogin->prompt);
if (rlogin->s)
sk_close(rlogin->s);
conf_free(rlogin->conf);
sfree(rlogin);
}
/*
* Stub routine (we don't have any need to reconfigure this backend).
*/
static void rlogin_reconfig(void *handle, Conf *conf)
{
}
/*
* Called to send data down the rlogin connection.
*/
static int rlogin_send(void *handle, const char *buf, int len)
{
Rlogin rlogin = (Rlogin) handle;
if (rlogin->s == NULL)
return 0;
if (rlogin->prompt) {
/*
* We're still prompting for a username, and aren't talking
* directly to the network connection yet.
*/
int ret = get_userpass_input(rlogin->prompt,
(unsigned char *)buf, len);
if (ret >= 0) {
rlogin_startup(rlogin, rlogin->prompt->prompts[0]->result);
/* that nulls out rlogin->prompt, so then we'll start sending
* data down the wire in the obvious way */
}
} else {
rlogin->bufsize = sk_write(rlogin->s, buf, len);
}
return rlogin->bufsize;
}
/*
* Called to query the current socket sendability status.
*/
static int rlogin_sendbuffer(void *handle)
{
Rlogin rlogin = (Rlogin) handle;
return rlogin->bufsize;
}
/*
* Called to set the size of the window
*/
static void rlogin_size(void *handle, int width, int height)
{
Rlogin rlogin = (Rlogin) handle;
char b[12] = { '\xFF', '\xFF', 0x73, 0x73, 0, 0, 0, 0, 0, 0, 0, 0 };
rlogin->term_width = width;
rlogin->term_height = height;
if (rlogin->s == NULL || !rlogin->cansize)
return;
b[6] = rlogin->term_width >> 8;
b[7] = rlogin->term_width & 0xFF;
b[4] = rlogin->term_height >> 8;
b[5] = rlogin->term_height & 0xFF;
rlogin->bufsize = sk_write(rlogin->s, b, 12);
return;
}
/*
* Send rlogin special codes.
*/
static void rlogin_special(void *handle, Telnet_Special code)
{
/* Do nothing! */
return;
}
/*
* Return a list of the special codes that make sense in this
* protocol.
*/
static const struct telnet_special *rlogin_get_specials(void *handle)
{
return NULL;
}
static int rlogin_connected(void *handle)
{
Rlogin rlogin = (Rlogin) handle;
return rlogin->s != NULL;
}
static int rlogin_sendok(void *handle)
{
/* Rlogin rlogin = (Rlogin) handle; */
return 1;
}
static void rlogin_unthrottle(void *handle, int backlog)
{
Rlogin rlogin = (Rlogin) handle;
sk_set_frozen(rlogin->s, backlog > RLOGIN_MAX_BACKLOG);
}
static int rlogin_ldisc(void *handle, int option)
{
/* Rlogin rlogin = (Rlogin) handle; */
return 0;
}
static void rlogin_provide_ldisc(void *handle, void *ldisc)
{
/* This is a stub. */
}
static void rlogin_provide_logctx(void *handle, void *logctx)
{
/* This is a stub. */
}
static int rlogin_exitcode(void *handle)
{
Rlogin rlogin = (Rlogin) handle;
if (rlogin->s != NULL)
return -1; /* still connected */
else if (rlogin->closed_on_socket_error)
return INT_MAX; /* a socket error counts as an unclean exit */
else
/* If we ever implement RSH, we'll probably need to do this properly */
return 0;
}
/*
* cfg_info for rlogin does nothing at all.
*/
static int rlogin_cfg_info(void *handle)
{
return 0;
}
Backend rlogin_backend = {
rlogin_init,
rlogin_free,
rlogin_reconfig,
rlogin_send,
rlogin_sendbuffer,
rlogin_size,
rlogin_special,
rlogin_get_specials,
rlogin_connected,
rlogin_exitcode,
rlogin_sendok,
rlogin_ldisc,
rlogin_provide_ldisc,
rlogin_provide_logctx,
rlogin_unthrottle,
rlogin_cfg_info,
NULL /* test_for_upstream */,
"rlogin",
PROT_RLOGIN,
513
};