putty/raw.c

346 строки
7.2 KiB
C

/*
* "Raw" backend.
*/
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include "putty.h"
#ifndef FALSE
#define FALSE 0
#endif
#ifndef TRUE
#define TRUE 1
#endif
#define RAW_MAX_BACKLOG 4096
typedef struct raw_backend_data {
const struct plug_function_table *fn;
/* the above field _must_ be first in the structure */
Socket s;
int closed_on_socket_error;
int bufsize;
void *frontend;
int sent_console_eof, sent_socket_eof;
} *Raw;
static void raw_size(void *handle, int width, int height);
static void c_write(Raw raw, char *buf, int len)
{
int backlog = from_backend(raw->frontend, 0, buf, len);
sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
}
static void raw_log(Plug plug, int type, SockAddr addr, int port,
const char *error_msg, int error_code)
{
Raw raw = (Raw) plug;
char addrbuf[256], *msg;
sk_getaddr(addr, addrbuf, lenof(addrbuf));
if (type == 0)
msg = dupprintf("Connecting to %s port %d", addrbuf, port);
else
msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
logevent(raw->frontend, msg);
sfree(msg);
}
static void raw_check_close(Raw raw)
{
/*
* Called after we send EOF on either the socket or the console.
* Its job is to wind up the session once we have sent EOF on both.
*/
if (raw->sent_console_eof && raw->sent_socket_eof) {
if (raw->s) {
sk_close(raw->s);
raw->s = NULL;
notify_remote_exit(raw->frontend);
}
}
}
static int raw_closing(Plug plug, const char *error_msg, int error_code,
int calling_back)
{
Raw raw = (Raw) plug;
if (error_msg) {
/* A socket error has occurred. */
if (raw->s) {
sk_close(raw->s);
raw->s = NULL;
raw->closed_on_socket_error = TRUE;
notify_remote_exit(raw->frontend);
}
logevent(raw->frontend, error_msg);
connection_fatal(raw->frontend, "%s", error_msg);
} else {
/* Otherwise, the remote side closed the connection normally. */
if (!raw->sent_console_eof && from_backend_eof(raw->frontend)) {
/*
* The front end wants us to close the outgoing side of the
* connection as soon as we see EOF from the far end.
*/
if (!raw->sent_socket_eof) {
if (raw->s)
sk_write_eof(raw->s);
raw->sent_socket_eof= TRUE;
}
}
raw->sent_console_eof = TRUE;
raw_check_close(raw);
}
return 0;
}
static int raw_receive(Plug plug, int urgent, char *data, int len)
{
Raw raw = (Raw) plug;
c_write(raw, data, len);
return 1;
}
static void raw_sent(Plug plug, int bufsize)
{
Raw raw = (Raw) plug;
raw->bufsize = bufsize;
}
/*
* Called to set up the raw 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 *raw_init(void *frontend_handle, void **backend_handle,
Conf *conf,
char *host, int port, char **realhost, int nodelay,
int keepalive)
{
static const struct plug_function_table fn_table = {
raw_log,
raw_closing,
raw_receive,
raw_sent
};
SockAddr addr;
const char *err;
Raw raw;
int addressfamily;
char *loghost;
raw = snew(struct raw_backend_data);
raw->fn = &fn_table;
raw->s = NULL;
raw->closed_on_socket_error = FALSE;
*backend_handle = raw;
raw->sent_console_eof = raw->sent_socket_eof = FALSE;
raw->bufsize = 0;
raw->frontend = frontend_handle;
addressfamily = conf_get_int(conf, CONF_addressfamily);
/*
* Try to find host.
*/
{
char *buf;
buf = dupprintf("Looking up host \"%s\"%s", host,
(addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
(addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" :
"")));
logevent(raw->frontend, buf);
sfree(buf);
}
addr = name_lookup(host, port, realhost, conf, addressfamily);
if ((err = sk_addr_error(addr)) != NULL) {
sk_addr_free(addr);
return err;
}
if (port < 0)
port = 23; /* default telnet port */
/*
* Open socket.
*/
raw->s = new_connection(addr, *realhost, port, 0, 1, nodelay, keepalive,
(Plug) raw, conf);
if ((err = sk_socket_error(raw->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';
}
return NULL;
}
static void raw_free(void *handle)
{
Raw raw = (Raw) handle;
if (raw->s)
sk_close(raw->s);
sfree(raw);
}
/*
* Stub routine (we don't have any need to reconfigure this backend).
*/
static void raw_reconfig(void *handle, Conf *conf)
{
}
/*
* Called to send data down the raw connection.
*/
static int raw_send(void *handle, char *buf, int len)
{
Raw raw = (Raw) handle;
if (raw->s == NULL)
return 0;
raw->bufsize = sk_write(raw->s, buf, len);
return raw->bufsize;
}
/*
* Called to query the current socket sendability status.
*/
static int raw_sendbuffer(void *handle)
{
Raw raw = (Raw) handle;
return raw->bufsize;
}
/*
* Called to set the size of the window
*/
static void raw_size(void *handle, int width, int height)
{
/* Do nothing! */
return;
}
/*
* Send raw special codes. We only handle outgoing EOF here.
*/
static void raw_special(void *handle, Telnet_Special code)
{
Raw raw = (Raw) handle;
if (code == TS_EOF && raw->s) {
sk_write_eof(raw->s);
raw->sent_socket_eof= TRUE;
raw_check_close(raw);
}
return;
}
/*
* Return a list of the special codes that make sense in this
* protocol.
*/
static const struct telnet_special *raw_get_specials(void *handle)
{
return NULL;
}
static int raw_connected(void *handle)
{
Raw raw = (Raw) handle;
return raw->s != NULL;
}
static int raw_sendok(void *handle)
{
return 1;
}
static void raw_unthrottle(void *handle, int backlog)
{
Raw raw = (Raw) handle;
sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
}
static int raw_ldisc(void *handle, int option)
{
if (option == LD_EDIT || option == LD_ECHO)
return 1;
return 0;
}
static void raw_provide_ldisc(void *handle, void *ldisc)
{
/* This is a stub. */
}
static void raw_provide_logctx(void *handle, void *logctx)
{
/* This is a stub. */
}
static int raw_exitcode(void *handle)
{
Raw raw = (Raw) handle;
if (raw->s != NULL)
return -1; /* still connected */
else if (raw->closed_on_socket_error)
return INT_MAX; /* a socket error counts as an unclean exit */
else
/* Exit codes are a meaningless concept in the Raw protocol */
return 0;
}
/*
* cfg_info for Raw does nothing at all.
*/
static int raw_cfg_info(void *handle)
{
return 0;
}
Backend raw_backend = {
raw_init,
raw_free,
raw_reconfig,
raw_send,
raw_sendbuffer,
raw_size,
raw_special,
raw_get_specials,
raw_connected,
raw_exitcode,
raw_sendok,
raw_ldisc,
raw_provide_ldisc,
raw_provide_logctx,
raw_unthrottle,
raw_cfg_info,
"raw",
PROT_RAW,
0
};