/*
- *
- * channels.c
- *
* Author: Tatu Ylonen <ylo@cs.hut.fi>
- *
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- *
- * Created: Fri Mar 24 16:35:24 1995 ylo
- *
* This file contains functions for generic socket connection forwarding.
* There is also code for initiating connection forwarding for X11 connections,
* arbitrary tcp/ip connections, and the authentication agent connection.
*
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ *
+ *
* SSH2 support added by Markus Friedl.
+ * Copyright (c) 1999,2000 Markus Friedl. All rights reserved.
+ * Copyright (c) 1999 Dug Song. All rights reserved.
+ * Copyright (c) 1999 Theo de Raadt. 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.
+ *
+ * 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 "includes.h"
-RCSID("$OpenBSD: channels.c,v 1.66 2000/08/19 21:55:51 markus Exp $");
+RCSID("$OpenBSD: channels.c,v 1.114 2001/05/08 19:17:30 markus Exp $");
+
+#include <openssl/rsa.h>
+#include <openssl/dsa.h>
#include "ssh.h"
+#include "ssh1.h"
+#include "ssh2.h"
#include "packet.h"
#include "xmalloc.h"
#include "buffer.h"
+#include "bufaux.h"
#include "uidswap.h"
-#include "readconf.h"
-#include "servconf.h"
-
+#include "log.h"
+#include "misc.h"
#include "channels.h"
#include "nchan.h"
#include "compat.h"
-
-#include "ssh2.h"
-
-#include <openssl/rsa.h>
-#include <openssl/dsa.h>
+#include "canohost.h"
#include "key.h"
#include "authfd.h"
/* Max len of agent socket */
#define MAX_SOCKET_NAME 100
-/* default window/packet sizes for tcp/x11-fwd-channel */
-#define CHAN_TCP_WINDOW_DEFAULT (8*1024)
-#define CHAN_TCP_PACKET_DEFAULT (CHAN_TCP_WINDOW_DEFAULT/2)
-#define CHAN_X11_WINDOW_DEFAULT (4*1024)
-#define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2)
-
/*
* Pointer to an array containing all allocated channels. The array is
* dynamically extended as needed.
*/
-static Channel *channels = NULL;
+static Channel **channels = NULL;
/*
* Size of the channel array. All slots of the array must always be
- * initialized (at least the type field); unused slots are marked with type
- * SSH_CHANNEL_FREE.
+ * initialized (at least the type field); unused slots set to NULL
*/
static int channels_alloc = 0;
/*
* Maximum file descriptor value used in any of the channels. This is
- * updated in channel_allocate.
+ * updated in channel_new.
*/
-static int channel_max_fd_value = 0;
+static int channel_max_fd = 0;
/* Name and directory of socket for authentication agent forwarding. */
static char *channel_forwarded_auth_socket_name = NULL;
/* Saved X11 authentication data. This is the real data. */
char *x11_saved_data = NULL;
-unsigned int x11_saved_data_len = 0;
+u_int x11_saved_data_len = 0;
/*
* Fake X11 authentication data. This is what the server will be sending us;
* we should replace any occurrences of this by the real data.
*/
char *x11_fake_data = NULL;
-unsigned int x11_fake_data_len;
+u_int x11_fake_data_len;
/*
* Data structure for storing which hosts are permitted for forward requests.
/* This is set to true if both sides support SSH_PROTOFLAG_HOST_IN_FWD_OPEN. */
static int have_hostname_in_open = 0;
+/* AF_UNSPEC or AF_INET or AF_INET6 */
+extern int IPv4or6;
+
+void port_open_helper(Channel *c, char *rtype);
+
/* Sets specific protocol options. */
void
have_hostname_in_open = hostname_in_open;
}
-/*
- * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually
- * called by the server, because the user could connect to any port anyway,
- * and the server has no way to know but to trust the client anyway.
- */
-
-void
-channel_permit_all_opens()
-{
- all_opens_permitted = 1;
-}
-
/* lookup channel by id */
Channel *
channel_lookup(int id)
{
Channel *c;
+
if (id < 0 || id > channels_alloc) {
log("channel_lookup: %d: bad id", id);
return NULL;
}
- c = &channels[id];
- if (c->type == SSH_CHANNEL_FREE) {
+ c = channels[id];
+ if (c == NULL) {
log("channel_lookup: %d: bad id: channel free", id);
return NULL;
}
*/
void
-channel_register_fds(Channel *c, int rfd, int wfd, int efd, int extusage)
+channel_register_fds(Channel *c, int rfd, int wfd, int efd,
+ int extusage, int nonblock)
{
/* Update the maximum file descriptor value. */
- if (rfd > channel_max_fd_value)
- channel_max_fd_value = rfd;
- if (wfd > channel_max_fd_value)
- channel_max_fd_value = wfd;
- if (efd > channel_max_fd_value)
- channel_max_fd_value = efd;
+ channel_max_fd = MAX(channel_max_fd, rfd);
+ channel_max_fd = MAX(channel_max_fd, wfd);
+ channel_max_fd = MAX(channel_max_fd, efd);
+
/* XXX set close-on-exec -markus */
c->rfd = rfd;
c->sock = (rfd == wfd) ? rfd : -1;
c->efd = efd;
c->extended_usage = extusage;
- if (rfd != -1)
- set_nonblock(rfd);
- if (wfd != -1)
- set_nonblock(wfd);
- if (efd != -1)
- set_nonblock(efd);
+
+ /* XXX ugly hack: nonblock is only set by the server */
+ if (nonblock && isatty(c->rfd)) {
+ debug("channel %d: rfd %d isatty", c->self, c->rfd);
+ c->isatty = 1;
+ if (!isatty(c->wfd)) {
+ error("channel %d: wfd %d is not a tty?",
+ c->self, c->wfd);
+ }
+ } else {
+ c->isatty = 0;
+ }
+
+ /* enable nonblocking mode */
+ if (nonblock) {
+ if (rfd != -1)
+ set_nonblock(rfd);
+ if (wfd != -1)
+ set_nonblock(wfd);
+ if (efd != -1)
+ set_nonblock(efd);
+ }
}
/*
* remote_name to be freed.
*/
-int
+Channel *
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
- int window, int maxpack, int extusage, char *remote_name)
+ int window, int maxpack, int extusage, char *remote_name, int nonblock)
{
int i, found;
Channel *c;
if (channels_alloc == 0) {
chan_init();
channels_alloc = 10;
- channels = xmalloc(channels_alloc * sizeof(Channel));
+ channels = xmalloc(channels_alloc * sizeof(Channel *));
for (i = 0; i < channels_alloc; i++)
- channels[i].type = SSH_CHANNEL_FREE;
+ channels[i] = NULL;
/*
* Kludge: arrange a call to channel_stop_listening if we
* terminate with fatal().
}
/* Try to find a free slot where to put the new channel. */
for (found = -1, i = 0; i < channels_alloc; i++)
- if (channels[i].type == SSH_CHANNEL_FREE) {
+ if (channels[i] == NULL) {
/* Found a free slot. */
found = i;
break;
/* There are no free slots. Take last+1 slot and expand the array. */
found = channels_alloc;
channels_alloc += 10;
- debug("channel: expanding %d", channels_alloc);
- channels = xrealloc(channels, channels_alloc * sizeof(Channel));
+ debug2("channel: expanding %d", channels_alloc);
+ channels = xrealloc(channels, channels_alloc * sizeof(Channel *));
for (i = found; i < channels_alloc; i++)
- channels[i].type = SSH_CHANNEL_FREE;
+ channels[i] = NULL;
}
- /* Initialize and return new channel number. */
- c = &channels[found];
+ /* Initialize and return new channel. */
+ c = channels[found] = xmalloc(sizeof(Channel));
buffer_init(&c->input);
buffer_init(&c->output);
buffer_init(&c->extended);
chan_init_iostates(c);
- channel_register_fds(c, rfd, wfd, efd, extusage);
+ channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
c->self = found;
c->type = type;
c->ctype = ctype;
c->dettach_user = NULL;
c->input_filter = NULL;
debug("channel %d: new [%s]", found, remote_name);
- return found;
-}
-/* old interface XXX */
-int
-channel_allocate(int type, int sock, char *remote_name)
-{
- return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name);
+ return c;
}
-
/* Close all channel fd/socket. */
void
/* Free the channel and close its fd/socket. */
void
-channel_free(int id)
+channel_free(Channel *c)
{
- Channel *c = channel_lookup(id);
- if (c == NULL)
- packet_disconnect("channel free: bad local channel %d", id);
- debug("channel_free: channel %d: status: %s", id, channel_open_message());
+ char *s;
+
+ s = channel_open_message();
+ debug("channel_free: channel %d: status: %s", c->self, s);
+ xfree(s);
+
if (c->dettach_user != NULL) {
- debug("channel_free: channel %d: dettaching channel user", id);
+ debug("channel_free: channel %d: dettaching channel user", c->self);
c->dettach_user(c->self, NULL);
}
if (c->sock != -1)
buffer_free(&c->input);
buffer_free(&c->output);
buffer_free(&c->extended);
- c->type = SSH_CHANNEL_FREE;
if (c->remote_name) {
xfree(c->remote_name);
c->remote_name = NULL;
}
+ channels[c->self] = NULL;
+ xfree(c);
}
/*
FD_SET(c->sock, readset);
}
+void
+channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ debug3("channel %d: waiting for connection", c->self);
+ FD_SET(c->sock, writeset);
+}
+
void
channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
{
packet_put_int(c->remote_id);
packet_send();
c->type = SSH_CHANNEL_CLOSED;
- debug("Closing channel %d after input drain.", c->self);
+ debug("channel %d: closing after input drain.", c->self);
}
}
channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
{
if (buffer_len(&c->output) == 0)
- channel_free(c->self);
+ chan_mark_dead(c);
else
FD_SET(c->sock, writeset);
}
int
x11_open_helper(Channel *c)
{
- unsigned char *ucp;
- unsigned int proto_len, data_len;
+ u_char *ucp;
+ u_int proto_len, data_len;
/* Check if the fixed size part of the packet is in buffer. */
if (buffer_len(&c->output) < 12)
return 0;
/* Parse the lengths of variable-length fields. */
- ucp = (unsigned char *) buffer_ptr(&c->output);
+ ucp = (u_char *) buffer_ptr(&c->output);
if (ucp[0] == 0x42) { /* Byte order MSB first. */
proto_len = 256 * ucp[6] + ucp[7];
data_len = 256 * ucp[8] + ucp[9];
* We have received an X11 connection that has bad
* authentication information.
*/
- log("X11 connection rejected because of wrong authentication.\r\n");
+ log("X11 connection rejected because of wrong authentication.");
buffer_clear(&c->input);
buffer_clear(&c->output);
close(c->sock);
}
}
+/* try to decode a socks4 header */
+int
+channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ u_char *p, *host;
+ int len, have, i, found;
+ char username[256];
+ struct {
+ u_int8_t version;
+ u_int8_t command;
+ u_int16_t dest_port;
+ struct in_addr dest_addr;
+ } s4_req, s4_rsp;
+
+ debug2("channel %d: decode socks4", c->self);
+
+ have = buffer_len(&c->input);
+ len = sizeof(s4_req);
+ if (have < len)
+ return 0;
+ p = buffer_ptr(&c->input);
+ for (found = 0, i = len; i < have; i++) {
+ if (p[i] == '\0') {
+ found = 1;
+ break;
+ }
+ if (i > 1024) {
+ /* the peer is probably sending garbage */
+ debug("channel %d: decode socks4: too long",
+ c->self);
+ return -1;
+ }
+ }
+ if (!found)
+ return 0;
+ buffer_get(&c->input, (char *)&s4_req.version, 1);
+ buffer_get(&c->input, (char *)&s4_req.command, 1);
+ buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
+ buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
+ have = buffer_len(&c->input);
+ p = buffer_ptr(&c->input);
+ len = strlen(p);
+ debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
+ if (len > have)
+ fatal("channel %d: decode socks4: len %d > have %d",
+ c->self, len, have);
+ strlcpy(username, p, sizeof(username));
+ buffer_consume(&c->input, len);
+ buffer_consume(&c->input, 1); /* trailing '\0' */
+
+ host = inet_ntoa(s4_req.dest_addr);
+ strlcpy(c->path, host, sizeof(c->path));
+ c->host_port = ntohs(s4_req.dest_port);
+
+ debug("channel %d: dynamic request: socks4 host %s port %u command %u",
+ c->self, host, c->host_port, s4_req.command);
+
+ if (s4_req.command != 1) {
+ debug("channel %d: cannot handle: socks4 cn %d",
+ c->self, s4_req.command);
+ return -1;
+ }
+ s4_rsp.version = 0; /* vn: 0 for reply */
+ s4_rsp.command = 90; /* cd: req granted */
+ s4_rsp.dest_port = 0; /* ignored */
+ s4_rsp.dest_addr.s_addr = INADDR_ANY; /* ignored */
+ buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
+ return 1;
+}
+
+/* dynamic port forwarding */
+void
+channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ u_char *p;
+ int have, ret;
+
+ have = buffer_len(&c->input);
+
+ debug2("channel %d: pre_dynamic: have %d", c->self, have);
+ /* buffer_dump(&c->input); */
+ /* check if the fixed size part of the packet is in buffer. */
+ if (have < 4) {
+ /* need more */
+ FD_SET(c->sock, readset);
+ return;
+ }
+ /* try to guess the protocol */
+ p = buffer_ptr(&c->input);
+ switch (p[0]) {
+ case 0x04:
+ ret = channel_decode_socks4(c, readset, writeset);
+ break;
+ default:
+ ret = -1;
+ break;
+ }
+ if (ret < 0) {
+ chan_mark_dead(c);
+ } else if (ret == 0) {
+ debug2("channel %d: pre_dynamic: need more", c->self);
+ /* need more */
+ FD_SET(c->sock, readset);
+ } else {
+ /* switch to the next state */
+ c->type = SSH_CHANNEL_OPENING;
+ port_open_helper(c, "direct-tcpip");
+ }
+}
+
/* This is our fake X11 server socket. */
void
channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
+ Channel *nc;
struct sockaddr addr;
- int newsock, newch;
+ int newsock;
socklen_t addrlen;
- char buf[16384], *remote_hostname;
+ char buf[16384], *remote_ipaddr;
int remote_port;
if (FD_ISSET(c->sock, readset)) {
error("accept: %.100s", strerror(errno));
return;
}
- remote_hostname = get_remote_hostname(newsock);
+ remote_ipaddr = get_peer_ipaddr(newsock);
remote_port = get_peer_port(newsock);
snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
- remote_hostname, remote_port);
+ remote_ipaddr, remote_port);
- newch = channel_new("x11",
+ nc = channel_new("accepted x11 socket",
SSH_CHANNEL_OPENING, newsock, newsock, -1,
c->local_window_max, c->local_maxpacket,
- 0, xstrdup(buf));
+ 0, xstrdup(buf), 1);
+ if (nc == NULL) {
+ close(newsock);
+ xfree(remote_ipaddr);
+ return;
+ }
if (compat20) {
packet_start(SSH2_MSG_CHANNEL_OPEN);
packet_put_cstring("x11");
- packet_put_int(newch);
+ packet_put_int(nc->self);
packet_put_int(c->local_window_max);
packet_put_int(c->local_maxpacket);
- /* originator host and port */
- packet_put_cstring(remote_hostname);
+ /* originator ipaddr and port */
+ packet_put_cstring(remote_ipaddr);
if (datafellows & SSH_BUG_X11FWD) {
debug("ssh2 x11 bug compat mode");
} else {
packet_send();
} else {
packet_start(SSH_SMSG_X11_OPEN);
- packet_put_int(newch);
+ packet_put_int(nc->self);
if (have_hostname_in_open)
packet_put_string(buf, strlen(buf));
packet_send();
}
- xfree(remote_hostname);
+ xfree(remote_ipaddr);
+ }
+}
+
+void
+port_open_helper(Channel *c, char *rtype)
+{
+ int direct;
+ char buf[1024];
+ char *remote_ipaddr = get_peer_ipaddr(c->sock);
+ u_short remote_port = get_peer_port(c->sock);
+
+ direct = (strcmp(rtype, "direct-tcpip") == 0);
+
+ snprintf(buf, sizeof buf,
+ "%s: listening port %d for %.100s port %d, "
+ "connect from %.200s port %d",
+ rtype, c->listening_port, c->path, c->host_port,
+ remote_ipaddr, remote_port);
+
+ xfree(c->remote_name);
+ c->remote_name = xstrdup(buf);
+
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN);
+ packet_put_cstring(rtype);
+ packet_put_int(c->self);
+ packet_put_int(c->local_window_max);
+ packet_put_int(c->local_maxpacket);
+ if (direct) {
+ /* target host, port */
+ packet_put_cstring(c->path);
+ packet_put_int(c->host_port);
+ } else {
+ /* listen address, port */
+ packet_put_cstring(c->path);
+ packet_put_int(c->listening_port);
+ }
+ /* originator host and port */
+ packet_put_cstring(remote_ipaddr);
+ packet_put_int(remote_port);
+ packet_send();
+ } else {
+ packet_start(SSH_MSG_PORT_OPEN);
+ packet_put_int(c->self);
+ packet_put_cstring(c->path);
+ packet_put_int(c->host_port);
+ if (have_hostname_in_open)
+ packet_put_cstring(c->remote_name);
+ packet_send();
}
+ xfree(remote_ipaddr);
}
/*
void
channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
+ Channel *nc;
struct sockaddr addr;
- int newsock, newch;
+ int newsock, nextstate;
socklen_t addrlen;
- char buf[1024], *remote_hostname;
- int remote_port;
+ char *rtype;
if (FD_ISSET(c->sock, readset)) {
debug("Connection to port %d forwarding "
"to %.100s port %d requested.",
c->listening_port, c->path, c->host_port);
+
+ rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ?
+ "forwarded-tcpip" : "direct-tcpip";
+ nextstate = (c->host_port == 0) ? SSH_CHANNEL_DYNAMIC :
+ SSH_CHANNEL_OPENING;
+
addrlen = sizeof(addr);
newsock = accept(c->sock, &addr, &addrlen);
if (newsock < 0) {
error("accept: %.100s", strerror(errno));
return;
}
- remote_hostname = get_remote_hostname(newsock);
- remote_port = get_peer_port(newsock);
- snprintf(buf, sizeof buf,
- "listen port %d for %.100s port %d, "
- "connect from %.200s port %d",
- c->listening_port, c->path, c->host_port,
- remote_hostname, remote_port);
- newch = channel_new("direct-tcpip",
- SSH_CHANNEL_OPENING, newsock, newsock, -1,
+ nc = channel_new(rtype,
+ nextstate, newsock, newsock, -1,
c->local_window_max, c->local_maxpacket,
- 0, xstrdup(buf));
- if (compat20) {
- packet_start(SSH2_MSG_CHANNEL_OPEN);
- packet_put_cstring("direct-tcpip");
- packet_put_int(newch);
- packet_put_int(c->local_window_max);
- packet_put_int(c->local_maxpacket);
- /* target host and port */
- packet_put_string(c->path, strlen(c->path));
- packet_put_int(c->host_port);
- /* originator host and port */
- packet_put_cstring(remote_hostname);
- packet_put_int(remote_port);
- packet_send();
- } else {
- packet_start(SSH_MSG_PORT_OPEN);
- packet_put_int(newch);
- packet_put_string(c->path, strlen(c->path));
- packet_put_int(c->host_port);
- if (have_hostname_in_open) {
- packet_put_string(buf, strlen(buf));
- }
- packet_send();
+ 0, xstrdup(rtype), 1);
+ if (nc == NULL) {
+ error("channel_post_port_listener: no new channel:");
+ close(newsock);
+ return;
}
- xfree(remote_hostname);
+ nc->listening_port = c->listening_port;
+ nc->host_port = c->host_port;
+ strlcpy(nc->path, c->path, sizeof(nc->path));
+
+ if (nextstate != SSH_CHANNEL_DYNAMIC)
+ port_open_helper(nc, rtype);
}
}
void
channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
+ Channel *nc;
+ int newsock;
struct sockaddr addr;
- int newsock, newch;
socklen_t addrlen;
if (FD_ISSET(c->sock, readset)) {
error("accept from auth socket: %.100s", strerror(errno));
return;
}
- newch = channel_allocate(SSH_CHANNEL_OPENING, newsock,
- xstrdup("accepted auth socket"));
- packet_start(SSH_SMSG_AGENT_OPEN);
- packet_put_int(newch);
+ nc = channel_new("accepted auth socket",
+ SSH_CHANNEL_OPENING, newsock, newsock, -1,
+ c->local_window_max, c->local_maxpacket,
+ 0, xstrdup("accepted auth socket"), 1);
+ if (nc == NULL) {
+ error("channel_post_auth_listener: channel_new failed");
+ close(newsock);
+ }
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN);
+ packet_put_cstring("auth-agent@openssh.com");
+ packet_put_int(nc->self);
+ packet_put_int(c->local_window_max);
+ packet_put_int(c->local_maxpacket);
+ } else {
+ packet_start(SSH_SMSG_AGENT_OPEN);
+ packet_put_int(nc->self);
+ }
+ packet_send();
+ }
+}
+
+void
+channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ int err = 0;
+ int sz = sizeof(err);
+
+ if (FD_ISSET(c->sock, writeset)) {
+ if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err,
+ &sz) < 0) {
+ err = errno;
+ error("getsockopt SO_ERROR failed");
+ }
+ if (err == 0) {
+ debug("channel %d: connected", c->self);
+ c->type = SSH_CHANNEL_OPEN;
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
+ packet_put_int(c->remote_id);
+ packet_put_int(c->self);
+ packet_put_int(c->local_window);
+ packet_put_int(c->local_maxpacket);
+ } else {
+ packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
+ packet_put_int(c->remote_id);
+ packet_put_int(c->self);
+ }
+ } else {
+ debug("channel %d: not connected: %s",
+ c->self, strerror(err));
+ if (compat20) {
+ packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(c->remote_id);
+ packet_put_int(SSH2_OPEN_CONNECT_FAILED);
+ if (!(datafellows & SSH_BUG_OPENFAILURE)) {
+ packet_put_cstring(strerror(err));
+ packet_put_cstring("");
+ }
+ } else {
+ packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(c->remote_id);
+ }
+ chan_mark_dead(c);
+ }
packet_send();
}
}
if (len <= 0) {
debug("channel %d: read<=0 rfd %d len %d",
c->self, c->rfd, len);
- if (compat13) {
+ if (c->type != SSH_CHANNEL_OPEN) {
+ debug("channel %d: not open", c->self);
+ chan_mark_dead(c);
+ return -1;
+ } else if (compat13) {
buffer_consume(&c->output, buffer_len(&c->output));
c->type = SSH_CHANNEL_INPUT_DRAINING;
- debug("Channel %d status set to input draining.", c->self);
+ debug("channel %d: status set to input draining.", c->self);
} else {
chan_read_failed(c);
}
}
if(c->input_filter != NULL) {
if (c->input_filter(c, buf, len) == -1) {
- debug("filter stops channel %d", c->self);
+ debug("channel %d: filter stops", c->self);
chan_read_failed(c);
}
} else {
int
channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
{
+ struct termios tio;
int len;
/* Send buffered output data to the socket. */
if (len < 0 && (errno == EINTR || errno == EAGAIN))
return 1;
if (len <= 0) {
- if (compat13) {
+ if (c->type != SSH_CHANNEL_OPEN) {
+ debug("channel %d: not open", c->self);
+ chan_mark_dead(c);
+ return -1;
+ } else if (compat13) {
buffer_consume(&c->output, buffer_len(&c->output));
- debug("Channel %d status set to input draining.", c->self);
+ debug("channel %d: status set to input draining.", c->self);
c->type = SSH_CHANNEL_INPUT_DRAINING;
} else {
chan_write_failed(c);
}
return -1;
}
+ if (compat20 && c->isatty) {
+ if (tcgetattr(c->wfd, &tio) == 0 &&
+ !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
+ /*
+ * Simulate echo to reduce the impact of
+ * traffic analysis. We need to match the
+ * size of a SSH2_MSG_CHANNEL_DATA message
+ * (4 byte channel id + data)
+ */
+ packet_send_ignore(4 + len);
+ packet_send();
+ }
+ }
buffer_consume(&c->output, len);
if (compat20 && len > 0) {
c->local_consumed += len;
buffer_len(&c->extended) > 0) {
len = write(c->efd, buffer_ptr(&c->extended),
buffer_len(&c->extended));
- debug("channel %d: written %d to efd %d",
+ debug2("channel %d: written %d to efd %d",
c->self, len, c->efd);
- if (len > 0) {
+ if (len < 0 && (errno == EINTR || errno == EAGAIN))
+ return 1;
+ if (len <= 0) {
+ debug2("channel %d: closing write-efd %d",
+ c->self, c->efd);
+ close(c->efd);
+ c->efd = -1;
+ } else {
buffer_consume(&c->extended, len);
c->local_consumed += len;
}
} else if (c->extended_usage == CHAN_EXTENDED_READ &&
FD_ISSET(c->efd, readset)) {
len = read(c->efd, buf, sizeof(buf));
- debug("channel %d: read %d from efd %d",
+ debug2("channel %d: read %d from efd %d",
c->self, len, c->efd);
- if (len == 0) {
- debug("channel %d: closing efd %d",
+ if (len < 0 && (errno == EINTR || errno == EAGAIN))
+ return 1;
+ if (len <= 0) {
+ debug2("channel %d: closing read-efd %d",
c->self, c->efd);
close(c->efd);
c->efd = -1;
- } else if (len > 0)
+ } else {
buffer_append(&c->extended, buf, len);
+ }
}
}
return 1;
}
int
-channel_check_window(Channel *c, fd_set * readset, fd_set * writeset)
+channel_check_window(Channel *c)
{
- if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
+ if (c->type == SSH_CHANNEL_OPEN &&
+ !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
c->local_window < c->local_window_max/2 &&
c->local_consumed > 0) {
packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
packet_put_int(c->remote_id);
packet_put_int(c->local_consumed);
packet_send();
- debug("channel %d: window %d sent adjust %d",
+ debug2("channel %d: window %d sent adjust %d",
c->self, c->local_window,
c->local_consumed);
c->local_window += c->local_consumed;
channel_handle_rfd(c, readset, writeset);
channel_handle_wfd(c, readset, writeset);
channel_handle_efd(c, readset, writeset);
- channel_check_window(c, readset, writeset);
+
+ channel_check_window(c);
}
void
channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
+ channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
+ channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
+ channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
+ channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
+ channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_2;
}
void
channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
+ channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
+ channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
+ channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
+ channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
}
void
channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
+ channel_pre[SSH_CHANNEL_DYNAMIC] = &channel_pre_dynamic;
channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
+ channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
+ channel_post[SSH_CHANNEL_DYNAMIC] = &channel_post_open_1;
}
void
did_init = 1;
}
for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
- if (c->type == SSH_CHANNEL_FREE)
+ c = channels[i];
+ if (c == NULL)
continue;
if (ftab[c->type] == NULL)
continue;
(*ftab[c->type])(c, readset, writeset);
- chan_delete_if_full_closed(c);
+ if (chan_is_dead(c)) {
+ /*
+ * we have to remove the fd's from the select mask
+ * before the channels are free'd and the fd's are
+ * closed
+ */
+ if (c->wfd != -1)
+ FD_CLR(c->wfd, writeset);
+ if (c->rfd != -1)
+ FD_CLR(c->rfd, readset);
+ if (c->efd != -1) {
+ if (c->extended_usage == CHAN_EXTENDED_READ)
+ FD_CLR(c->efd, readset);
+ if (c->extended_usage == CHAN_EXTENDED_WRITE)
+ FD_CLR(c->efd, writeset);
+ }
+ channel_free(c);
+ }
}
}
void
-channel_prepare_select(fd_set * readset, fd_set * writeset)
+channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
+ int rekeying)
{
- channel_handler(channel_pre, readset, writeset);
+ int n;
+ u_int sz;
+
+ n = MAX(*maxfdp, channel_max_fd);
+
+ sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
+ if (*readsetp == NULL || n > *maxfdp) {
+ if (*readsetp)
+ xfree(*readsetp);
+ if (*writesetp)
+ xfree(*writesetp);
+ *readsetp = xmalloc(sz);
+ *writesetp = xmalloc(sz);
+ *maxfdp = n;
+ }
+ memset(*readsetp, 0, sz);
+ memset(*writesetp, 0, sz);
+
+ if (!rekeying)
+ channel_handler(channel_pre, *readsetp, *writesetp);
}
void
channel_handler(channel_post, readset, writeset);
}
-/* If there is data to send to the connection, send some of it now. */
+/* If there is data to send to the connection, enqueue some of it now. */
void
channel_output_poll()
Channel *c;
for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
+
+ c = channels[i];
+ if (c == NULL)
+ continue;
/* We are only interested in channels that can have buffered incoming data. */
if (compat13) {
} else {
if (c->type != SSH_CHANNEL_OPEN)
continue;
- if (c->istate != CHAN_INPUT_OPEN &&
- c->istate != CHAN_INPUT_WAIT_DRAIN)
- continue;
}
if (compat20 &&
(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
- debug("channel: %d: no data after CLOSE", c->self);
+ /* XXX is this true? */
+ debug2("channel %d: no data after CLOSE", c->self);
continue;
}
/* Get the amount of buffered data for this channel. */
- len = buffer_len(&c->input);
- if (len > 0) {
+ if ((c->istate == CHAN_INPUT_OPEN ||
+ c->istate == CHAN_INPUT_WAIT_DRAIN) &&
+ (len = buffer_len(&c->input)) > 0) {
/* Send some data for the other side over the secure connection. */
if (compat20) {
if (len > c->remote_window)
c->remote_window > 0 &&
(len = buffer_len(&c->extended)) > 0 &&
c->extended_usage == CHAN_EXTENDED_READ) {
+ debug2("channel %d: rwin %d elen %d euse %d",
+ c->self, c->remote_window, buffer_len(&c->extended),
+ c->extended_usage);
if (len > c->remote_window)
len = c->remote_window;
if (len > c->remote_maxpacket)
packet_send();
buffer_consume(&c->extended, len);
c->remote_window -= len;
+ debug2("channel %d: sent ext data %d", c->self, len);
}
}
}
*/
void
-channel_input_data(int type, int plen)
+channel_input_data(int type, int plen, void *ctxt)
{
int id;
char *data;
- unsigned int data_len;
+ u_int data_len;
Channel *c;
/* Get the channel number and verify it. */
xfree(data);
}
void
-channel_input_extended_data(int type, int plen)
+channel_input_extended_data(int type, int plen, void *ctxt)
{
int id;
int tcode;
char *data;
- unsigned int data_len;
+ u_int data_len;
Channel *c;
/* Get the channel number and verify it. */
xfree(data);
return;
}
- debug("channel %d: rcvd ext data %d", c->self, data_len);
+ debug2("channel %d: rcvd ext data %d", c->self, data_len);
c->local_window -= data_len;
buffer_append(&c->extended, data, data_len);
xfree(data);
int
channel_not_very_much_buffered_data()
{
- unsigned int i;
+ u_int i;
Channel *c;
for (i = 0; i < channels_alloc; i++) {
- c = &channels[i];
- if (c->type == SSH_CHANNEL_OPEN) {
+ c = channels[i];
+ if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) {
debug("channel %d: big input buffer %d",
c->self, buffer_len(&c->input));
}
void
-channel_input_ieof(int type, int plen)
+channel_input_ieof(int type, int plen, void *ctxt)
{
int id;
Channel *c;
}
void
-channel_input_close(int type, int plen)
+channel_input_close(int type, int plen, void *ctxt)
{
int id;
Channel *c;
/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
void
-channel_input_oclose(int type, int plen)
+channel_input_oclose(int type, int plen, void *ctxt)
{
int id = packet_get_int();
Channel *c = channel_lookup(id);
}
void
-channel_input_close_confirmation(int type, int plen)
+channel_input_close_confirmation(int type, int plen, void *ctxt)
{
int id = packet_get_int();
Channel *c = channel_lookup(id);
if (c->type != SSH_CHANNEL_CLOSED)
packet_disconnect("Received close confirmation for "
"non-closed channel %d (type %d).", id, c->type);
- channel_free(c->self);
+ channel_free(c);
}
void
-channel_input_open_confirmation(int type, int plen)
+channel_input_open_confirmation(int type, int plen, void *ctxt)
{
int id, remote_id;
Channel *c;
c->remote_maxpacket = packet_get_int();
packet_done();
if (c->cb_fn != NULL && c->cb_event == type) {
- debug("callback start");
+ debug2("callback start");
c->cb_fn(c->self, c->cb_arg);
- debug("callback done");
+ debug2("callback done");
}
debug("channel %d: open confirm rwindow %d rmax %d", c->self,
c->remote_window, c->remote_maxpacket);
}
}
+char *
+reason2txt(int reason)
+{
+ switch(reason) {
+ case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
+ return "administratively prohibited";
+ case SSH2_OPEN_CONNECT_FAILED:
+ return "connect failed";
+ case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
+ return "unknown channel type";
+ case SSH2_OPEN_RESOURCE_SHORTAGE:
+ return "resource shortage";
+ }
+ return "unkown reason";
+}
+
void
-channel_input_open_failure(int type, int plen)
+channel_input_open_failure(int type, int plen, void *ctxt)
{
- int id;
+ int id, reason;
+ char *msg = NULL, *lang = NULL;
Channel *c;
if (!compat20)
packet_disconnect("Received open failure for "
"non-opening channel %d.", id);
if (compat20) {
- int reason = packet_get_int();
- char *msg = packet_get_string(NULL);
- char *lang = packet_get_string(NULL);
- log("channel_open_failure: %d: reason %d: %s", id, reason, msg);
+ reason = packet_get_int();
+ if (!(datafellows & SSH_BUG_OPENFAILURE)) {
+ msg = packet_get_string(NULL);
+ lang = packet_get_string(NULL);
+ }
packet_done();
- xfree(msg);
- xfree(lang);
+ log("channel %d: open failed: %s%s%s", id,
+ reason2txt(reason), msg ? ": ": "", msg ? msg : "");
+ if (msg != NULL)
+ xfree(msg);
+ if (lang != NULL)
+ xfree(lang);
}
/* Free the channel. This will also close the socket. */
- channel_free(id);
+ channel_free(c);
}
void
-channel_input_channel_request(int type, int plen)
+channel_input_channel_request(int type, int plen, void *ctxt)
{
int id;
Channel *c;
packet_disconnect("Received request for "
"non-open channel %d.", id);
if (c->cb_fn != NULL && c->cb_event == type) {
- debug("callback start");
+ debug2("callback start");
c->cb_fn(c->self, c->cb_arg);
- debug("callback done");
+ debug2("callback done");
} else {
char *service = packet_get_string(NULL);
- debug("channel: %d rcvd request for %s", c->self, service);
-debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
+ debug("channel %d: rcvd request for %s", c->self, service);
+ debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
xfree(service);
}
}
void
-channel_input_window_adjust(int type, int plen)
+channel_input_window_adjust(int type, int plen, void *ctxt)
{
Channel *c;
int id, adjust;
}
adjust = packet_get_int();
packet_done();
- debug("channel %d: rcvd adjust %d", id, adjust);
+ debug2("channel %d: rcvd adjust %d", id, adjust);
c->remote_window += adjust;
}
channel_stop_listening()
{
int i;
+ Channel *c;
+
for (i = 0; i < channels_alloc; i++) {
- switch (channels[i].type) {
- case SSH_CHANNEL_AUTH_SOCKET:
- close(channels[i].sock);
- remove(channels[i].path);
- channel_free(i);
- break;
- case SSH_CHANNEL_PORT_LISTENER:
- case SSH_CHANNEL_X11_LISTENER:
- close(channels[i].sock);
- channel_free(i);
- break;
- default:
- break;
+ c = channels[i];
+ if (c != NULL) {
+ switch (c->type) {
+ case SSH_CHANNEL_AUTH_SOCKET:
+ close(c->sock);
+ unlink(c->path);
+ channel_free(c);
+ break;
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_X11_LISTENER:
+ close(c->sock);
+ channel_free(c);
+ break;
+ default:
+ break;
+ }
}
}
}
channel_close_all()
{
int i;
- for (i = 0; i < channels_alloc; i++)
- if (channels[i].type != SSH_CHANNEL_FREE)
- channel_close_fds(&channels[i]);
-}
-/* Returns the maximum file descriptor number used by the channels. */
-
-int
-channel_max_fd()
-{
- return channel_max_fd_value;
+ for (i = 0; i < channels_alloc; i++)
+ if (channels[i] != NULL)
+ channel_close_fds(channels[i]);
}
/* Returns true if any channel is still open. */
int
channel_still_open()
{
- unsigned int i;
- for (i = 0; i < channels_alloc; i++)
- switch (channels[i].type) {
- case SSH_CHANNEL_FREE:
+ int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c == NULL)
+ continue;
+ switch (c->type) {
case SSH_CHANNEL_X11_LISTENER:
case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
case SSH_CHANNEL_CLOSED:
case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_DYNAMIC:
+ case SSH_CHANNEL_CONNECTING:
continue;
case SSH_CHANNEL_LARVAL:
if (!compat20)
fatal("cannot happen: OUT_DRAIN");
return 1;
default:
- fatal("channel_still_open: bad channel type %d", channels[i].type);
+ fatal("channel_still_open: bad channel type %d", c->type);
/* NOTREACHED */
}
+ }
return 0;
}
+/* Returns the id of an open channel suitable for keepaliving */
+
+int
+channel_find_open()
+{
+ int i;
+ Channel *c;
+
+ for (i = 0; i < channels_alloc; i++) {
+ c = channels[i];
+ if (c == NULL)
+ continue;
+ switch (c->type) {
+ case SSH_CHANNEL_CLOSED:
+ case SSH_CHANNEL_DYNAMIC:
+ case SSH_CHANNEL_X11_LISTENER:
+ case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
+ case SSH_CHANNEL_OPENING:
+ case SSH_CHANNEL_CONNECTING:
+ continue;
+ case SSH_CHANNEL_LARVAL:
+ case SSH_CHANNEL_AUTH_SOCKET:
+ case SSH_CHANNEL_OPEN:
+ case SSH_CHANNEL_X11_OPEN:
+ return i;
+ case SSH_CHANNEL_INPUT_DRAINING:
+ case SSH_CHANNEL_OUTPUT_DRAINING:
+ if (!compat13)
+ fatal("cannot happen: OUT_DRAIN");
+ return i;
+ default:
+ fatal("channel_find_open: bad channel type %d", c->type);
+ /* NOTREACHED */
+ }
+ }
+ return -1;
+}
+
+
/*
* Returns a message describing the currently open forwarded connections,
* suitable for sending to the client. The message contains crlf pairs for
channel_open_message()
{
Buffer buffer;
+ Channel *c;
+ char buf[1024], *cp;
int i;
- char buf[512], *cp;
buffer_init(&buffer);
snprintf(buf, sizeof buf, "The following connections are open:\r\n");
buffer_append(&buffer, buf, strlen(buf));
for (i = 0; i < channels_alloc; i++) {
- Channel *c = &channels[i];
+ c = channels[i];
+ if (c == NULL)
+ continue;
switch (c->type) {
- case SSH_CHANNEL_FREE:
case SSH_CHANNEL_X11_LISTENER:
case SSH_CHANNEL_PORT_LISTENER:
+ case SSH_CHANNEL_RPORT_LISTENER:
case SSH_CHANNEL_CLOSED:
case SSH_CHANNEL_AUTH_SOCKET:
continue;
case SSH_CHANNEL_LARVAL:
case SSH_CHANNEL_OPENING:
+ case SSH_CHANNEL_CONNECTING:
+ case SSH_CHANNEL_DYNAMIC:
case SSH_CHANNEL_OPEN:
case SSH_CHANNEL_X11_OPEN:
case SSH_CHANNEL_INPUT_DRAINING:
* Initiate forwarding of connections to local port "port" through the secure
* channel to host:port from remote side.
*/
+int
+channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
+ u_short port_to_connect, int gateway_ports)
+{
+ return channel_request_forwarding(
+ NULL, listen_port,
+ host_to_connect, port_to_connect,
+ gateway_ports, /*remote_fwd*/ 0);
+}
-void
-channel_request_local_forwarding(u_short port, const char *host,
- u_short host_port, int gateway_ports)
+/*
+ * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
+ * (SSH_CHANNEL_RPORT_LISTENER).
+ */
+int
+channel_request_forwarding(
+ const char *listen_address, u_short listen_port,
+ const char *host_to_connect, u_short port_to_connect,
+ int gateway_ports, int remote_fwd)
{
- int success, ch, sock, on = 1;
+ Channel *c;
+ int success, sock, on = 1, ctype;
struct addrinfo hints, *ai, *aitop;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
+ const char *host;
struct linger linger;
- if (strlen(host) > sizeof(channels[0].path) - 1)
- packet_disconnect("Forward host name too long.");
+ success = 0;
+
+ if (remote_fwd) {
+ host = listen_address;
+ ctype = SSH_CHANNEL_RPORT_LISTENER;
+ } else {
+ host = host_to_connect;
+ ctype =SSH_CHANNEL_PORT_LISTENER;
+ }
+
+ if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
+ error("Forward host name too long.");
+ return success;
+ }
+ /* XXX listen_address is currently ignored */
/*
* getaddrinfo returns a loopback address if the hostname is
* set to NULL and hints.ai_flags is not AI_PASSIVE
hints.ai_family = IPv4or6;
hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
hints.ai_socktype = SOCK_STREAM;
- snprintf(strport, sizeof strport, "%d", port);
+ snprintf(strport, sizeof strport, "%d", listen_port);
if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
packet_disconnect("getaddrinfo: fatal error");
- success = 0;
for (ai = aitop; ai; ai = ai->ai_next) {
if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
continue;
if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
- error("channel_request_local_forwarding: getnameinfo failed");
+ error("channel_request_forwarding: getnameinfo failed");
continue;
}
/* Create a port to listen for the host. */
error("bind: %.100s", strerror(errno));
else
verbose("bind: %.100s", strerror(errno));
-
+
close(sock);
continue;
}
continue;
}
/* Allocate a channel number for the socket. */
- ch = channel_new(
- "port listener", SSH_CHANNEL_PORT_LISTENER,
- sock, sock, -1,
+ c = channel_new("port listener", ctype, sock, sock, -1,
CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
- 0, xstrdup("port listener"));
- strlcpy(channels[ch].path, host, sizeof(channels[ch].path));
- channels[ch].host_port = host_port;
- channels[ch].listening_port = port;
+ 0, xstrdup("port listener"), 1);
+ if (c == NULL) {
+ error("channel_request_forwarding: channel_new failed");
+ close(sock);
+ continue;
+ }
+ strlcpy(c->path, host, sizeof(c->path));
+ c->host_port = port_to_connect;
+ c->listening_port = listen_port;
success = 1;
}
if (success == 0)
- packet_disconnect("cannot listen port: %d", port);
+ error("channel_request_forwarding: cannot listen to port: %d",
+ listen_port);
freeaddrinfo(aitop);
+ return success;
}
/*
*/
void
-channel_request_remote_forwarding(u_short listen_port, const char *host_to_connect,
- u_short port_to_connect)
+channel_request_remote_forwarding(u_short listen_port,
+ const char *host_to_connect, u_short port_to_connect)
{
- int payload_len;
+ int payload_len, type, success = 0;
+
/* Record locally that connection to this host/port is permitted. */
if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
fatal("channel_request_remote_forwarding: too many forwards");
- permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
- permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
- permitted_opens[num_permitted_opens].listen_port = listen_port;
- num_permitted_opens++;
-
/* Send the forward request to the remote side. */
if (compat20) {
const char *address_to_bind = "0.0.0.0";
packet_put_char(0); /* boolean: want reply */
packet_put_cstring(address_to_bind);
packet_put_int(listen_port);
+ packet_send();
+ packet_write_wait();
+ /* Assume that server accepts the request */
+ success = 1;
} else {
packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
packet_put_int(listen_port);
packet_put_int(port_to_connect);
packet_send();
packet_write_wait();
- /*
- * Wait for response from the remote side. It will send a disconnect
- * message on failure, and we will never see it here.
- */
- packet_read_expect(&payload_len, SSH_SMSG_SUCCESS);
+
+ /* Wait for response from the remote side. */
+ type = packet_read(&payload_len);
+ switch (type) {
+ case SSH_SMSG_SUCCESS:
+ success = 1;
+ break;
+ case SSH_SMSG_FAILURE:
+ log("Warning: Server denied remote port forwarding.");
+ break;
+ default:
+ /* Unknown packet */
+ packet_disconnect("Protocol error for port forward request:"
+ "received packet type %d.", type);
+ }
+ }
+ if (success) {
+ permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
+ permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
+ permitted_opens[num_permitted_opens].listen_port = listen_port;
+ num_permitted_opens++;
}
}
hostname = packet_get_string(NULL);
host_port = packet_get_int();
+#ifndef HAVE_CYGWIN
/*
* Check that an unprivileged user is not trying to forward a
* privileged port.
if (port < IPPORT_RESERVED && !is_root)
packet_disconnect("Requested forwarding of port %d but user is not root.",
port);
- /*
- * Initiate forwarding,
- */
+#endif
+ /* Initiate forwarding */
channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
/* Free the argument string. */
xfree(hostname);
}
-/* XXX move to aux.c */
+/*
+ * Permits opening to any host/port if permitted_opens[] is empty. This is
+ * usually called by the server, because the user could connect to any port
+ * anyway, and the server has no way to know but to trust the client anyway.
+ */
+void
+channel_permit_all_opens()
+{
+ if (num_permitted_opens == 0)
+ all_opens_permitted = 1;
+}
+
+void
+channel_add_permitted_opens(char *host, int port)
+{
+ if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
+ fatal("channel_request_remote_forwarding: too many forwards");
+ debug("allow port forwarding to host %s port %d", host, port);
+
+ permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
+ permitted_opens[num_permitted_opens].port_to_connect = port;
+ num_permitted_opens++;
+
+ all_opens_permitted = 0;
+}
+
+void
+channel_clear_permitted_opens(void)
+{
+ int i;
+
+ for (i = 0; i < num_permitted_opens; i++)
+ xfree(permitted_opens[i].host_to_connect);
+ num_permitted_opens = 0;
+
+}
+
+
+/* return socket to remote host, port */
int
-channel_connect_to(const char *host, u_short host_port)
+connect_to(const char *host, u_short port)
{
struct addrinfo hints, *ai, *aitop;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
memset(&hints, 0, sizeof(hints));
hints.ai_family = IPv4or6;
hints.ai_socktype = SOCK_STREAM;
- snprintf(strport, sizeof strport, "%d", host_port);
+ snprintf(strport, sizeof strport, "%d", port);
if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
- error("%.100s: unknown host (%s)", host, gai_strerror(gaierr));
+ error("connect_to %.100s: unknown host (%s)", host,
+ gai_strerror(gaierr));
return -1;
}
for (ai = aitop; ai; ai = ai->ai_next) {
continue;
if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
- error("channel_connect_to: getnameinfo failed");
+ error("connect_to: getnameinfo failed");
continue;
}
- /* Create the socket. */
sock = socket(ai->ai_family, SOCK_STREAM, 0);
if (sock < 0) {
error("socket: %.100s", strerror(errno));
continue;
}
- /* Connect to the host/port. */
- if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
- error("connect %.100s port %s: %.100s", ntop, strport,
+ if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
+ fatal("connect_to: F_SETFL: %s", strerror(errno));
+ if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
+ errno != EINPROGRESS) {
+ error("connect_to %.100s port %s: %.100s", ntop, strport,
strerror(errno));
close(sock);
- continue; /* fail -- try next */
+ continue; /* fail -- try next */
}
break; /* success */
}
freeaddrinfo(aitop);
if (!ai) {
- error("connect %.100s port %d: failed.", host, host_port);
+ error("connect_to %.100s port %d: failed.", host, port);
return -1;
}
/* success */
return sock;
}
+int
+channel_connect_by_listen_adress(u_short listen_port)
+{
+ int i;
+
+ for (i = 0; i < num_permitted_opens; i++)
+ if (permitted_opens[i].listen_port == listen_port)
+ return connect_to(
+ permitted_opens[i].host_to_connect,
+ permitted_opens[i].port_to_connect);
+ error("WARNING: Server requests forwarding for unknown listen_port %d",
+ listen_port);
+ return -1;
+}
+
+/* Check if connecting to that port is permitted and connect. */
+int
+channel_connect_to(const char *host, u_short port)
+{
+ int i, permit;
+
+ permit = all_opens_permitted;
+ if (!permit) {
+ for (i = 0; i < num_permitted_opens; i++)
+ if (permitted_opens[i].port_to_connect == port &&
+ strcmp(permitted_opens[i].host_to_connect, host) == 0)
+ permit = 1;
+
+ }
+ if (!permit) {
+ log("Received request to connect to host %.100s port %d, "
+ "but the request was denied.", host, port);
+ return -1;
+ }
+ return connect_to(host, port);
+}
+
/*
* This is called after receiving PORT_OPEN message. This attempts to
* connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
*/
void
-channel_input_port_open(int type, int plen)
+channel_input_port_open(int type, int plen, void *ctxt)
{
+ Channel *c = NULL;
u_short host_port;
char *host, *originator_string;
- int remote_channel, sock = -1, newch, i, denied;
- unsigned int host_len, originator_len;
-
- /* Get remote channel number. */
- remote_channel = packet_get_int();
+ int remote_id, sock = -1;
- /* Get host name to connect to. */
- host = packet_get_string(&host_len);
-
- /* Get port to connect to. */
+ remote_id = packet_get_int();
+ host = packet_get_string(NULL);
host_port = packet_get_int();
- /* Get remote originator name. */
if (have_hostname_in_open) {
- originator_string = packet_get_string(&originator_len);
- originator_len += 4; /* size of packet_int */
+ originator_string = packet_get_string(NULL);
} else {
originator_string = xstrdup("unknown (remote did not supply name)");
- originator_len = 0; /* no originator supplied */
}
-
- packet_integrity_check(plen,
- 4 + 4 + host_len + 4 + originator_len, SSH_MSG_PORT_OPEN);
-
- /* Check if opening that port is permitted. */
- denied = 0;
- if (!all_opens_permitted) {
- /* Go trough all permitted ports. */
- for (i = 0; i < num_permitted_opens; i++)
- if (permitted_opens[i].port_to_connect == host_port &&
- strcmp(permitted_opens[i].host_to_connect, host) == 0)
- break;
-
- /* Check if we found the requested port among those permitted. */
- if (i >= num_permitted_opens) {
- /* The port is not permitted. */
- log("Received request to connect to %.100s:%d, but the request was denied.",
- host, host_port);
- denied = 1;
+ packet_done();
+ sock = channel_connect_to(host, host_port);
+ if (sock != -1) {
+ c = channel_new("connected socket",
+ SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
+ originator_string, 1);
+ if (c == NULL) {
+ error("channel_input_port_open: channel_new failed");
+ close(sock);
+ } else {
+ c->remote_id = remote_id;
}
}
- sock = denied ? -1 : channel_connect_to(host, host_port);
- if (sock > 0) {
- /* Allocate a channel for this connection. */
- newch = channel_allocate(SSH_CHANNEL_OPEN, sock, originator_string);
- channels[newch].remote_id = remote_channel;
-
- packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remote_channel);
- packet_put_int(newch);
- packet_send();
- } else {
+ if (c == NULL) {
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
+ packet_put_int(remote_id);
packet_send();
}
xfree(host);
continue;
sock = socket(ai->ai_family, SOCK_STREAM, 0);
if (sock < 0) {
- if (errno != EINVAL) {
+ if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
error("socket: %.100s", strerror(errno));
return NULL;
} else {
- debug("Socket family %d not supported [X11 disp create]", ai->ai_family);
+ debug("x11_create_display_inet: Socket family %d not supported",
+ ai->ai_family);
continue;
}
}
break;
#endif
}
+ freeaddrinfo(aitop);
if (num_socks > 0)
break;
}
}
/* Set up a suitable value for the DISPLAY variable. */
-
if (gethostname(hostname, sizeof(hostname)) < 0)
fatal("gethostname: %.100s", strerror(errno));
#ifdef IPADDR_IN_DISPLAY
- /*
+ /*
* HPUX detects the local hostname in the DISPLAY variable and tries
* to set up a shared memory connection to the server, which it
* incorrectly supposes to be local.
memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
/* Set DISPLAY to <ip address>:screen.display */
- snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr),
- display_number, screen_number);
+ snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr),
+ display_number, screen_number);
}
#else /* IPADDR_IN_DISPLAY */
/* Just set DISPLAY to hostname:screen.display */
snprintf(display, sizeof display, "%.400s:%d.%d", hostname,
- display_number, screen_number);
+ display_number, screen_number);
#endif /* IPADDR_IN_DISPLAY */
/* Allocate a channel for each socket. */
(void) channel_new("x11 listener",
SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
- 0, xstrdup("X11 inet listener"));
+ 0, xstrdup("X11 inet listener"), 1);
}
/* Return a suitable value for the DISPLAY environment variable. */
static
int
-connect_local_xsocket(unsigned int dnr)
+connect_local_xsocket(u_int dnr)
{
static const char *const x_sockets[] = {
X_UNIX_PATH "%u",
*/
void
-x11_input_open(int type, int plen)
+x11_input_open(int type, int plen, void *ctxt)
{
- int remote_channel, sock = 0, newch;
+ Channel *c = NULL;
+ int remote_id, sock = 0;
char *remote_host;
- unsigned int remote_len;
- /* Get remote channel number. */
- remote_channel = packet_get_int();
+ debug("Received X11 open request.");
- /* Get remote originator name. */
+ remote_id = packet_get_int();
if (have_hostname_in_open) {
- remote_host = packet_get_string(&remote_len);
- remote_len += 4;
+ remote_host = packet_get_string(NULL);
} else {
remote_host = xstrdup("unknown (remote did not supply name)");
- remote_len = 0;
}
-
- debug("Received X11 open request.");
- packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN);
+ packet_done();
/* Obtain a connection to the real X display. */
sock = x11_connect_display();
- if (sock == -1) {
+ if (sock != -1) {
+ /* Allocate a channel for this connection. */
+ c = channel_new("connected x11 socket",
+ SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
+ remote_host, 1);
+ if (c == NULL) {
+ error("x11_input_open: channel_new failed");
+ close(sock);
+ } else {
+ c->remote_id = remote_id;
+ }
+ }
+ if (c == NULL) {
/* Send refusal to the remote host. */
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
- packet_send();
+ packet_put_int(remote_id);
} else {
- /* Allocate a channel for this connection. */
- newch = channel_allocate(
- (x11_saved_proto == NULL) ?
- SSH_CHANNEL_OPEN : SSH_CHANNEL_X11_OPEN,
- sock, remote_host);
- channels[newch].remote_id = remote_channel;
-
/* Send a confirmation to the remote host. */
packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remote_channel);
- packet_put_int(newch);
- packet_send();
+ packet_put_int(remote_id);
+ packet_put_int(c->self);
+ }
+ packet_send();
+}
+
+/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
+void
+deny_input_open(int type, int plen, void *ctxt)
+{
+ int rchan = packet_get_int();
+ switch(type){
+ case SSH_SMSG_AGENT_OPEN:
+ error("Warning: ssh server tried agent forwarding.");
+ break;
+ case SSH_SMSG_X11_OPEN:
+ error("Warning: ssh server tried X11 forwarding.");
+ break;
+ default:
+ error("deny_input_open: type %d plen %d", type, plen);
+ break;
}
+ error("Warning: this is probably a break in attempt by a malicious server.");
+ packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(rchan);
+ packet_send();
}
/*
x11_request_forwarding_with_spoofing(int client_session_id,
const char *proto, const char *data)
{
- unsigned int data_len = (unsigned int) strlen(data) / 2;
- unsigned int i, value;
+ u_int data_len = (u_int) strlen(data) / 2;
+ u_int i, value, len;
char *new_data;
int screen_number;
const char *cp;
x11_fake_data_len = data_len;
/* Convert the fake data into hex. */
- new_data = xmalloc(2 * data_len + 1);
+ len = 2 * data_len + 1;
+ new_data = xmalloc(len);
for (i = 0; i < data_len; i++)
- sprintf(new_data + 2 * i, "%02x", (unsigned char) x11_fake_data[i]);
+ snprintf(new_data + 2 * i, len - 2 * i,
+ "%02x", (u_char) x11_fake_data[i]);
/* Send the request packet. */
if (compat20) {
void
cleanup_socket(void)
{
- remove(channel_forwarded_auth_socket_name);
+ unlink(channel_forwarded_auth_socket_name);
rmdir(channel_forwarded_auth_socket_dir);
}
int
auth_input_request_forwarding(struct passwd * pw)
{
- int sock, newch;
+ Channel *nc;
+ int sock;
struct sockaddr_un sunaddr;
if (auth_get_socket_name() != NULL)
fatal("Protocol error: authentication forwarding requested twice.");
/* Temporarily drop privileged uid for mkdir/bind. */
- temporarily_use_uid(pw->pw_uid);
+ temporarily_use_uid(pw);
/* Allocate a buffer for the socket name, and format the name. */
channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME);
packet_disconnect("listen: %.100s", strerror(errno));
/* Allocate a channel for the authentication agent socket. */
- newch = channel_allocate(SSH_CHANNEL_AUTH_SOCKET, sock,
- xstrdup("auth socket"));
- strlcpy(channels[newch].path, channel_forwarded_auth_socket_name,
- sizeof(channels[newch].path));
+ nc = channel_new("auth socket",
+ SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
+ CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
+ 0, xstrdup("auth socket"), 1);
+ if (nc == NULL) {
+ error("auth_input_request_forwarding: channel_new failed");
+ close(sock);
+ return 0;
+ }
+ strlcpy(nc->path, channel_forwarded_auth_socket_name, sizeof(nc->path));
return 1;
}
/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
void
-auth_input_open_request(int type, int plen)
+auth_input_open_request(int type, int plen, void *ctxt)
{
- int remch, sock, newch;
+ Channel *c = NULL;
+ int remote_id, sock;
char *dummyname;
packet_integrity_check(plen, 4, type);
/* Read the remote channel number from the message. */
- remch = packet_get_int();
+ remote_id = packet_get_int();
/*
* Get a connection to the local authentication agent (this may again
* because authentication forwarding is only enabled if we have an
* agent.
*/
- if (sock < 0) {
+ if (sock >= 0) {
+ dummyname = xstrdup("authentication agent connection");
+ c = channel_new("", SSH_CHANNEL_OPEN, sock, sock, -1, 0, 0, 0, dummyname, 1);
+ if (c == NULL) {
+ error("auth_input_open_request: channel_new failed");
+ close(sock);
+ } else {
+ c->remote_id = remote_id;
+ }
+ }
+ if (c == NULL) {
packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remch);
- packet_send();
- return;
+ packet_put_int(remote_id);
+ } else {
+ /* Send a confirmation to the remote host. */
+ debug("Forwarding authentication connection.");
+ packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
+ packet_put_int(remote_id);
+ packet_put_int(c->self);
}
- debug("Forwarding authentication connection.");
-
- /*
- * Dummy host name. This will be freed when the channel is freed; it
- * will still be valid in the packet_put_string below since the
- * channel cannot yet be freed at that point.
- */
- dummyname = xstrdup("authentication agent connection");
-
- newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname);
- channels[newch].remote_id = remch;
-
- /* Send a confirmation to the remote host. */
- packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remch);
- packet_put_int(newch);
packet_send();
}
}
c->dettach_user = NULL;
}
-void
+void
channel_register_filter(int id, channel_filter_fn *fn)
{
Channel *c = channel_lookup(id);
}
void
-channel_set_fds(int id, int rfd, int wfd, int efd, int extusage)
+channel_set_fds(int id, int rfd, int wfd, int efd,
+ int extusage, int nonblock)
{
Channel *c = channel_lookup(id);
if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
fatal("channel_activate for non-larval channel %d.", id);
-
- channel_register_fds(c, rfd, wfd, efd, extusage);
+ channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
c->type = SSH_CHANNEL_OPEN;
/* XXX window size? */
- c->local_window = c->local_window_max = c->local_maxpacket/2;
+ c->local_window = c->local_window_max = c->local_maxpacket * 2;
packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
packet_put_int(c->remote_id);
packet_put_int(c->local_window);
andersk / openssh.git / blobdiff