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/*
* Dropbear SSH
*
* Copyright (c) 2002,2003 Matt Johnston
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE. */
#include "includes.h"
#include "options.h"
#include "dbutil.h"
#include "tcpfwd.h"
#include "channel.h"
#include "runopts.h"
#include "session.h"
#include "ssh.h"
#ifdef ENABLE_CLI_REMOTETCPFWD
static int newtcpforwarded(struct Channel * channel);
const struct ChanType cli_chan_tcpremote = {
1, /* sepfds */
"forwarded-tcpip",
newtcpforwarded,
NULL,
NULL,
NULL
};
#endif
#ifdef ENABLE_CLI_LOCALTCPFWD
static int cli_localtcp(unsigned int listenport, const char* remoteaddr,
unsigned int remoteport);
static const struct ChanType cli_chan_tcplocal = {
1, /* sepfds */
"direct-tcpip",
NULL,
NULL,
NULL,
NULL
};
#endif
#ifdef ENABLE_CLI_LOCALTCPFWD
void setup_localtcp() {
int ret;
TRACE(("enter setup_localtcp"))
if (cli_opts.localfwds == NULL) {
TRACE(("cli_opts.localfwds == NULL"))
}
while (cli_opts.localfwds != NULL) {
ret = cli_localtcp(cli_opts.localfwds->listenport,
cli_opts.localfwds->connectaddr,
cli_opts.localfwds->connectport);
if (ret == DROPBEAR_FAILURE) {
dropbear_log(LOG_WARNING, "Failed local port forward %d:%s:%d",
cli_opts.localfwds->listenport,
cli_opts.localfwds->connectaddr,
cli_opts.localfwds->connectport);
}
cli_opts.localfwds = cli_opts.localfwds->next;
}
TRACE(("leave setup_localtcp"))
}
static int cli_localtcp(unsigned int listenport, const char* remoteaddr,
unsigned int remoteport) {
struct TCPListener* tcpinfo = NULL;
int ret;
TRACE(("enter cli_localtcp: %d %s %d", listenport, remoteaddr,
remoteport));
tcpinfo = (struct TCPListener*)m_malloc(sizeof(struct TCPListener));
tcpinfo->sendaddr = m_strdup(remoteaddr);
tcpinfo->sendport = remoteport;
if (opts.listen_fwd_all) {
tcpinfo->listenaddr = m_strdup("");
} else {
tcpinfo->listenaddr = m_strdup("localhost");
}
tcpinfo->listenport = listenport;
tcpinfo->chantype = &cli_chan_tcplocal;
tcpinfo->tcp_type = direct;
ret = listen_tcpfwd(tcpinfo);
if (ret == DROPBEAR_FAILURE) {
m_free(tcpinfo);
}
TRACE(("leave cli_localtcp: %d", ret))
return ret;
}
#endif /* ENABLE_CLI_LOCALTCPFWD */
#ifdef ENABLE_CLI_REMOTETCPFWD
static void send_msg_global_request_remotetcp(int port) {
char* listenspec = NULL;
TRACE(("enter send_msg_global_request_remotetcp"))
CHECKCLEARTOWRITE();
buf_putbyte(ses.writepayload, SSH_MSG_GLOBAL_REQUEST);
buf_putstring(ses.writepayload, "tcpip-forward", 13);
buf_putbyte(ses.writepayload, 1); /* want_reply */
if (opts.listen_fwd_all) {
listenspec = "";
} else {
listenspec = "localhost";
}
/* TODO: IPv6? */;
buf_putstring(ses.writepayload, listenspec, strlen(listenspec));
buf_putint(ses.writepayload, port);
encrypt_packet();
TRACE(("leave send_msg_global_request_remotetcp"))
}
/* The only global success/failure messages are for remotetcp.
* Since there isn't any identifier in these messages, we have to rely on them
* being in the same order as we sent the requests. This is the ordering
* of the cli_opts.remotefwds list */
void cli_recv_msg_request_success() {
/* Nothing in the packet. We just mark off that we have received the reply,
* so that we can report failure for later ones. */
struct TCPFwdList * iter = NULL;
iter = cli_opts.remotefwds;
while (iter != NULL) {
if (!iter->have_reply)
{
iter->have_reply = 1;
return;
}
iter = iter->next;
}
}
void cli_recv_msg_request_failure() {
struct TCPFwdList * iter = NULL;
iter = cli_opts.remotefwds;
while (iter != NULL) {
if (!iter->have_reply)
{
iter->have_reply = 1;
dropbear_log(LOG_WARNING, "Remote TCP forward request failed (port %d -> %s:%d)", iter->listenport, iter->connectaddr, iter->connectport);
return;
}
iter = iter->next;
}
}
void setup_remotetcp() {
struct TCPFwdList * iter = NULL;
TRACE(("enter setup_remotetcp"))
if (cli_opts.remotefwds == NULL) {
TRACE(("cli_opts.remotefwds == NULL"))
}
iter = cli_opts.remotefwds;
while (iter != NULL) {
send_msg_global_request_remotetcp(iter->listenport);
iter = iter->next;
}
TRACE(("leave setup_remotetcp"))
}
static int newtcpforwarded(struct Channel * channel) {
unsigned int origport;
struct TCPFwdList * iter = NULL;
char portstring[NI_MAXSERV];
int sock;
int err = SSH_OPEN_ADMINISTRATIVELY_PROHIBITED;
/* We don't care what address they connected to */
buf_eatstring(ses.payload);
origport = buf_getint(ses.payload);
/* Find which port corresponds */
iter = cli_opts.remotefwds;
while (iter != NULL) {
if (origport == iter->listenport) {
break;
}
iter = iter->next;
}
if (iter == NULL) {
/* We didn't request forwarding on that port */
dropbear_log(LOG_INFO, "Server send unrequested port, from port %d",
origport);
goto out;
}
snprintf(portstring, sizeof(portstring), "%d", iter->connectport);
sock = connect_remote(iter->connectaddr, portstring, 1, NULL);
if (sock < 0) {
TRACE(("leave newtcpdirect: sock failed"))
err = SSH_OPEN_CONNECT_FAILED;
goto out;
}
ses.maxfd = MAX(ses.maxfd, sock);
/* We don't set readfd, that will get set after the connection's
* progress succeeds */
channel->writefd = sock;
channel->initconn = 1;
err = SSH_OPEN_IN_PROGRESS;
out:
TRACE(("leave newtcpdirect: err %d", err))
return err;
}
#endif /* ENABLE_CLI_REMOTETCPFWD */
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