+/*
+ * Telnet backend.
+ */
+
#include <stdio.h>
#include <stdlib.h>
#define TELOPT_AUTHENTICATION 37 /* Authenticate */
#define TELOPT_ENCRYPT 38 /* Encryption option */
#define TELOPT_NEW_ENVIRON 39 /* New - Environment variables */
+#define TELOPT_TN3270E 40 /* TN3270 enhancements */
+#define TELOPT_XAUTH 41
+#define TELOPT_CHARSET 42 /* Character set */
+#define TELOPT_RSP 43 /* Remote serial port */
+#define TELOPT_COM_PORT_OPTION 44 /* Com port control */
+#define TELOPT_SLE 45 /* Suppress local echo */
+#define TELOPT_STARTTLS 46 /* Start TLS */
+#define TELOPT_KERMIT 47 /* Automatic Kermit file transfer */
+#define TELOPT_SEND_URL 48
+#define TELOPT_FORWARD_X 49
+#define TELOPT_PRAGMA_LOGON 138
+#define TELOPT_SSPI_LOGON 139
+#define TELOPT_PRAGMA_HEARTBEAT 140
#define TELOPT_EXOPL 255 /* extended-options-list */
#define TELQUAL_IS 0 /* option is... */
i(AUTHENTICATION);
i(ENCRYPT);
i(NEW_ENVIRON);
+ i(TN3270E);
+ i(XAUTH);
+ i(CHARSET);
+ i(RSP);
+ i(COM_PORT_OPTION);
+ i(SLE);
+ i(STARTTLS);
+ i(KERMIT);
+ i(SEND_URL);
+ i(FORWARD_X);
+ i(PRAGMA_LOGON);
+ i(SSPI_LOGON);
+ i(PRAGMA_HEARTBEAT);
i(EXOPL);
#undef i
return "<unknown>";
{ WILL, WONT, DO, DONT, TELOPT_TSPEED, OPTINDEX_TSPEED, REQUESTED };
static const struct Opt o_ttype =
{ WILL, WONT, DO, DONT, TELOPT_TTYPE, OPTINDEX_TTYPE, REQUESTED };
-static const struct Opt o_oenv = { WILL, WONT, DO, DONT, TELOPT_OLD_ENVIRON,
- OPTINDEX_OENV, INACTIVE
-};
-static const struct Opt o_nenv = { WILL, WONT, DO, DONT, TELOPT_NEW_ENVIRON,
- OPTINDEX_NENV, REQUESTED
-};
+static const struct Opt o_oenv =
+ { WILL, WONT, DO, DONT, TELOPT_OLD_ENVIRON, OPTINDEX_OENV, INACTIVE };
+static const struct Opt o_nenv =
+ { WILL, WONT, DO, DONT, TELOPT_NEW_ENVIRON, OPTINDEX_NENV, REQUESTED };
static const struct Opt o_echo =
{ DO, DONT, WILL, WONT, TELOPT_ECHO, OPTINDEX_ECHO, REQUESTED };
static const struct Opt o_we_sga =
} state;
Config cfg;
+
+ Pinger pinger;
} *Telnet;
#define TELNET_MAX_BACKLOG 4096
#define SB_DELTA 1024
-static void c_write1(Telnet telnet, int c)
+static void c_write(Telnet telnet, char *buf, int len)
{
int backlog;
- char cc = (char) c;
- backlog = from_backend(telnet->frontend, 0, &cc, 1);
+ backlog = from_backend(telnet->frontend, 0, buf, len);
sk_set_frozen(telnet->s, backlog > TELNET_MAX_BACKLOG);
}
}
/*
* If we reach here, the option was one we weren't prepared to
- * cope with. So send a negative ack.
+ * cope with. If the request was positive (WILL or DO), we send
+ * a negative ack to indicate refusal. If the request was
+ * negative (WONT / DONT), we must do nothing.
*/
- send_opt(telnet, (cmd == WILL ? DONT : WONT), option);
+ if (cmd == WILL || cmd == DO)
+ send_opt(telnet, (cmd == WILL ? DONT : WONT), option);
}
static void process_subneg(Telnet telnet)
b[n++] = IAC;
b[n++] = SE;
telnet->bufsize = sk_write(telnet->s, (char *)b, n);
- logbuf = dupprintf("client:\tSB %s IS %s", telopt(telnet->sb_opt),
- n == 6 ? "<nothing>" : "<stuff>");
+ logbuf = dupprintf("client:\tSB %s IS %s%s%s%s",
+ telopt(telnet->sb_opt),
+ *telnet->cfg.username ? "USER=" : "",
+ telnet->cfg.username,
+ *telnet->cfg.username ? " " : "",
+ n == 6 ? "<nothing>" :
+ (*telnet->cfg.environmt ? "<stuff>" : ""));
logevent(telnet->frontend, logbuf);
sfree(logbuf);
}
static void do_telnet_read(Telnet telnet, char *buf, int len)
{
+ char *outbuf = NULL;
+ int outbuflen = 0, outbufsize = 0;
+
+#define ADDTOBUF(c) do { \
+ if (outbuflen >= outbufsize) { \
+ outbufsize = outbuflen + 256; \
+ outbuf = sresize(outbuf, outbufsize, char); \
+ } \
+ outbuf[outbuflen++] = (c); \
+} while (0)
while (len--) {
int c = (unsigned char) *buf++;
telnet->state = SEENIAC;
else {
if (!telnet->in_synch)
- c_write1(telnet, c);
+ ADDTOBUF(c);
#if 1
/* I can't get the F***ing winsock to insert the urgent IAC
} else {
/* ignore everything else; print it if it's IAC */
if (c == IAC) {
- c_write1(telnet, c);
+ ADDTOBUF(c);
}
telnet->state = TOP_LEVEL;
}
else {
subneg_addchar:
if (telnet->sb_len >= telnet->sb_size) {
- unsigned char *newbuf;
telnet->sb_size += SB_DELTA;
- newbuf = (telnet->sb_buf ?
- srealloc(telnet->sb_buf, telnet->sb_size) :
- smalloc(telnet->sb_size));
- if (newbuf)
- telnet->sb_buf = newbuf;
- else
- telnet->sb_size -= SB_DELTA;
+ telnet->sb_buf = sresize(telnet->sb_buf, telnet->sb_size,
+ unsigned char);
}
- if (telnet->sb_len < telnet->sb_size)
- telnet->sb_buf[telnet->sb_len++] = c;
+ telnet->sb_buf[telnet->sb_len++] = c;
telnet->state = SUBNEGOT; /* in case we came here by goto */
}
break;
break;
}
}
+
+ if (outbuflen)
+ c_write(telnet, outbuf, outbuflen);
+ sfree(outbuf);
+}
+
+static void telnet_log(Plug plug, int type, SockAddr addr, int port,
+ const char *error_msg, int error_code)
+{
+ Telnet telnet = (Telnet) 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(telnet->frontend, msg);
}
-static int telnet_closing(Plug plug, char *error_msg, int error_code,
+static int telnet_closing(Plug plug, const char *error_msg, int error_code,
int calling_back)
{
Telnet telnet = (Telnet) plug;
if (telnet->s) {
sk_close(telnet->s);
telnet->s = NULL;
+ notify_remote_exit(telnet->frontend);
}
if (error_msg) {
- /* A socket error has occurred. */
logevent(telnet->frontend, error_msg);
- connection_fatal("%s", error_msg);
- } /* Otherwise, the remote side closed the connection normally. */
+ connection_fatal(telnet->frontend, "%s", error_msg);
+ }
+ /* Otherwise, the remote side closed the connection normally. */
return 0;
}
* Also places the canonical host name into `realhost'. It must be
* freed by the caller.
*/
-static char *telnet_init(void *frontend_handle, void **backend_handle,
- Config *cfg,
- char *host, int port, char **realhost, int nodelay)
+static const char *telnet_init(void *frontend_handle, void **backend_handle,
+ Config *cfg,
+ char *host, int port, char **realhost,
+ int nodelay, int keepalive)
{
static const struct plug_function_table fn_table = {
+ telnet_log,
telnet_closing,
telnet_receive,
telnet_sent
};
SockAddr addr;
- char *err;
+ const char *err;
Telnet telnet;
- telnet = smalloc(sizeof(*telnet));
+ telnet = snew(struct telnet_tag);
telnet->fn = &fn_table;
telnet->cfg = *cfg; /* STRUCTURE COPY */
telnet->s = NULL;
telnet->term_width = telnet->cfg.width;
telnet->term_height = telnet->cfg.height;
telnet->state = TOP_LEVEL;
+ telnet->ldisc = NULL;
+ telnet->pinger = NULL;
*backend_handle = telnet;
/*
*/
{
char *buf;
- buf = dupprintf("Looking up host \"%s\"", host);
+ buf = dupprintf("Looking up host \"%s\"%s", host,
+ (cfg->addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
+ (cfg->addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" :
+ "")));
logevent(telnet->frontend, buf);
sfree(buf);
}
- addr = name_lookup(host, port, realhost, &telnet->cfg);
- if ((err = sk_addr_error(addr)) != NULL)
+ addr = name_lookup(host, port, realhost, &telnet->cfg, cfg->addressfamily);
+ if ((err = sk_addr_error(addr)) != NULL) {
+ sk_addr_free(addr);
return err;
+ }
if (port < 0)
port = 23; /* default telnet port */
/*
* Open socket.
*/
- {
- char *buf, addrbuf[100];
- sk_getaddr(addr, addrbuf, 100);
- buf = dupprintf("Connecting to %s port %d", addrbuf, port);
- logevent(telnet->frontend, buf);
- sfree(buf);
- }
telnet->s = new_connection(addr, *realhost, port, 0, 1,
- nodelay, (Plug) telnet, &telnet->cfg);
+ nodelay, keepalive, (Plug) telnet, &telnet->cfg);
if ((err = sk_socket_error(telnet->s)) != NULL)
return err;
- sk_addr_free(addr);
+ telnet->pinger = pinger_new(&telnet->cfg, &telnet_backend, telnet);
/*
* Initialise option states.
*/
telnet->in_synch = FALSE;
+ /*
+ * We can send special commands from the start.
+ */
+ update_specials_menu(telnet->frontend);
+
return NULL;
}
+static void telnet_free(void *handle)
+{
+ Telnet telnet = (Telnet) handle;
+
+ sfree(telnet->sb_buf);
+ if (telnet->s)
+ sk_close(telnet->s);
+ if (telnet->pinger)
+ pinger_free(telnet->pinger);
+ sfree(telnet);
+}
/*
* Reconfigure the Telnet backend. There's no immediate action
* necessary, in this backend: we just save the fresh config for
static void telnet_reconfig(void *handle, Config *cfg)
{
Telnet telnet = (Telnet) handle;
+ pinger_reconfig(telnet->pinger, &telnet->cfg, cfg);
telnet->cfg = *cfg; /* STRUCTURE COPY */
}
{
Telnet telnet = (Telnet) handle;
unsigned char *p, *end;
- static unsigned char iac[2] = { IAC, IAC };
- static unsigned char cr[2] = { CR, NUL };
+ static const unsigned char iac[2] = { IAC, IAC };
+ static const unsigned char cr[2] = { CR, NUL };
#if 0
- static unsigned char nl[2] = { CR, LF };
+ static const unsigned char nl[2] = { CR, LF };
#endif
if (telnet->s == NULL)
telnet->bufsize = sk_write(telnet->s, (char *)b, 2);
break;
case TS_EOL:
- /* In BINARY mode, CR-LF becomes just CR. */
+ /* In BINARY mode, CR-LF becomes just CR -
+ * and without the NUL suffix too. */
if (telnet->opt_states[o_we_bin.index] == ACTIVE)
- telnet->bufsize = sk_write(telnet->s, "\r", 2);
+ telnet->bufsize = sk_write(telnet->s, "\r", 1);
else
telnet->bufsize = sk_write(telnet->s, "\r\n", 2);
break;
telnet->bufsize = sk_write(telnet->s, (char *)b, 2);
}
break;
+ default:
+ break; /* never heard of it */
}
}
-static Socket telnet_socket(void *handle)
+static const struct telnet_special *telnet_get_specials(void *handle)
+{
+ static const struct telnet_special specials[] = {
+ {"Are You There", TS_AYT},
+ {"Break", TS_BRK},
+ {"Synch", TS_SYNCH},
+ {"Erase Character", TS_EC},
+ {"Erase Line", TS_EL},
+ {"Go Ahead", TS_GA},
+ {"No Operation", TS_NOP},
+ {NULL, TS_SEP},
+ {"Abort Process", TS_ABORT},
+ {"Abort Output", TS_AO},
+ {"Interrupt Process", TS_IP},
+ {"Suspend Process", TS_SUSP},
+ {NULL, TS_SEP},
+ {"End Of Record", TS_EOR},
+ {"End Of File", TS_EOF},
+ {NULL, TS_EXITMENU}
+ };
+ return specials;
+}
+
+static int telnet_connected(void *handle)
{
Telnet telnet = (Telnet) handle;
- return telnet->s;
+ return telnet->s != NULL;
}
static int telnet_sendok(void *handle)
static int telnet_exitcode(void *handle)
{
- /* Telnet telnet = (Telnet) handle; */
- /* Telnet doesn't transmit exit codes back to the client */
+ Telnet telnet = (Telnet) handle;
+ if (telnet->s != NULL)
+ return -1; /* still connected */
+ else
+ /* Telnet doesn't transmit exit codes back to the client */
+ return 0;
+}
+
+/*
+ * cfg_info for Telnet does nothing at all.
+ */
+static int telnet_cfg_info(void *handle)
+{
return 0;
}
Backend telnet_backend = {
telnet_init,
+ telnet_free,
telnet_reconfig,
telnet_send,
telnet_sendbuffer,
telnet_size,
telnet_special,
- telnet_socket,
+ telnet_get_specials,
+ telnet_connected,
telnet_exitcode,
telnet_sendok,
telnet_ldisc,
telnet_provide_ldisc,
telnet_provide_logctx,
telnet_unthrottle,
+ telnet_cfg_info,
23
};