]> andersk Git - openssh.git/blobdiff - channels.c
- (stevesk) OpenSSH CVS update:
[openssh.git] / channels.c
index 3710b2fd41cf031e42b9223576a5563fa828d2ac..49023a278b225e7d9489337e8a0d689430538e92 100644 (file)
@@ -1,29 +1,51 @@
 /*
- *
- * 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 1.63 2000/06/25 20:17:57 provos Exp $");
+RCSID("$OpenBSD: channels.c,v 1.75 2000/12/05 20:34:09 markus Exp $");
 
 #include "ssh.h"
 #include "packet.h"
 #include "xmalloc.h"
 #include "buffer.h"
-#include "authfd.h"
 #include "uidswap.h"
 #include "readconf.h"
 #include "servconf.h"
@@ -34,18 +56,17 @@ RCSID("$OpenBSD: channels.c,v 1.63 2000/06/25 20:17:57 provos Exp $");
 
 #include "ssh2.h"
 
+#include <openssl/rsa.h>
+#include <openssl/dsa.h>
+#include "key.h"
+#include "authfd.h"
+
 /* Maximum number of fake X11 displays to try. */
 #define MAX_DISPLAYS  1000
 
 /* 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.
@@ -153,7 +174,8 @@ channel_lookup(int id)
  */
 
 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)
@@ -169,12 +191,16 @@ channel_register_fds(Channel *c, int rfd, int wfd, int efd, int extusage)
        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);
+
+       /* enable nonblocking mode */
+       if (nonblock) {
+               if (rfd != -1)
+                       set_nonblock(rfd);
+               if (wfd != -1)
+                       set_nonblock(wfd);
+               if (efd != -1)
+                       set_nonblock(efd);
+       }
 }
 
 /*
@@ -184,7 +210,7 @@ channel_register_fds(Channel *c, int rfd, int wfd, int efd, int extusage)
 
 int
 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;
@@ -213,7 +239,7 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd,
                /* 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);
+               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;
@@ -224,7 +250,7 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd,
        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;
@@ -240,6 +266,7 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd,
        c->cb_arg = NULL;
        c->cb_event = 0;
        c->dettach_user = NULL;
+       c->input_filter = NULL;
        debug("channel %d: new [%s]", found, remote_name);
        return found;
 }
@@ -247,7 +274,7 @@ channel_new(char *ctype, int type, int rfd, int wfd, int efd,
 int
 channel_allocate(int type, int sock, char *remote_name)
 {
-       return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name);
+       return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name, 1);
 }
 
 
@@ -318,6 +345,13 @@ channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
        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)
 {
@@ -526,7 +560,7 @@ channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
                newch = channel_new("x11",
                    SSH_CHANNEL_OPENING, newsock, newsock, -1,
                    c->local_window_max, c->local_maxpacket,
-                   0, xstrdup(buf));
+                   0, xstrdup(buf), 1);
                if (compat20) {
                        packet_start(SSH2_MSG_CHANNEL_OPEN);
                        packet_put_cstring("x11");
@@ -561,9 +595,12 @@ channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
        struct sockaddr addr;
        int newsock, newch;
        socklen_t addrlen;
-       char buf[1024], *remote_hostname;
+       char buf[1024], *remote_hostname, *rtype;
        int remote_port;
 
+       rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ?
+           "forwarded-tcpip" : "direct-tcpip";
+
        if (FD_ISSET(c->sock, readset)) {
                debug("Connection to port %d forwarding "
                    "to %.100s port %d requested.",
@@ -581,19 +618,26 @@ channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
                    "connect from %.200s port %d",
                    c->listening_port, c->path, c->host_port,
                    remote_hostname, remote_port);
-               newch = channel_new("direct-tcpip",
+
+               newch = channel_new(rtype,
                    SSH_CHANNEL_OPENING, newsock, newsock, -1,
                    c->local_window_max, c->local_maxpacket,
-                   0, xstrdup(buf));
+                   0, xstrdup(buf), 1);
                if (compat20) {
                        packet_start(SSH2_MSG_CHANNEL_OPEN);
-                       packet_put_cstring("direct-tcpip");
+                       packet_put_cstring(rtype);
                        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);
+                       if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
+                               /* listen address, port */
+                               packet_put_string(c->path, strlen(c->path));
+                               packet_put_int(c->listening_port);
+                       } else {
+                               /* target host, 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);
@@ -630,14 +674,46 @@ channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
                        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);
+               newch = 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 (compat20) {
+                       packet_start(SSH2_MSG_CHANNEL_OPEN);
+                       packet_put_cstring("auth-agent@openssh.com");
+                       packet_put_int(newch);
+                       packet_put_int(c->local_window_max);
+                       packet_put_int(c->local_maxpacket);
+               } else {
+                       packet_start(SSH_SMSG_AGENT_OPEN);
+                       packet_put_int(newch);
+               }
                packet_send();
        }
 }
 
+void
+channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
+{
+       if (FD_ISSET(c->sock, writeset)) {
+               int err = 0;
+               int sz = sizeof(err);
+               c->type = SSH_CHANNEL_OPEN;
+                if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, &sz) < 0) {
+                       debug("getsockopt SO_ERROR failed");
+               } else {
+                       if (err == 0) {
+                               debug("channel %d: connected)", c->self);
+                       } else {
+                               debug("channel %d: not connected: %s",
+                                   c->self, strerror(err));
+                               chan_read_failed(c);
+                               chan_write_failed(c);
+                       }
+               }
+       }
+}
+
 int
 channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
 {
@@ -661,7 +737,14 @@ channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
                        }
                        return -1;
                }
-               buffer_append(&c->input, buf, len);
+               if(c->input_filter != NULL) {
+                       if (c->input_filter(c, buf, len) == -1) {
+                               debug("filter stops channel %d", c->self);
+                               chan_read_failed(c);
+                       }
+               } else {
+                       buffer_append(&c->input, buf, len);
+               }
        }
        return 1;
 }
@@ -708,7 +791,7 @@ channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
                    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) {
                                buffer_consume(&c->extended, len);
@@ -717,7 +800,7 @@ channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
                } 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",
@@ -740,7 +823,7 @@ channel_check_window(Channel *c, fd_set * readset, fd_set * writeset)
                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;
@@ -786,11 +869,17 @@ channel_handler_init_20(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_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;
 }
 
 void
@@ -803,12 +892,14 @@ channel_handler_init_13(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_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;
 }
 
 void
@@ -819,11 +910,13 @@ channel_handler_init_15(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_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;
 }
 
 void
@@ -969,7 +1062,7 @@ channel_output_poll()
  */
 
 void
-channel_input_data(int type, int plen)
+channel_input_data(int type, int plen, void *ctxt)
 {
        int id;
        char *data;
@@ -1014,7 +1107,7 @@ channel_input_data(int type, int plen)
        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;
@@ -1047,7 +1140,7 @@ channel_input_extended_data(int type, int plen)
                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);
@@ -1084,7 +1177,7 @@ channel_not_very_much_buffered_data()
 }
 
 void
-channel_input_ieof(int type, int plen)
+channel_input_ieof(int type, int plen, void *ctxt)
 {
        int id;
        Channel *c;
@@ -1099,7 +1192,7 @@ channel_input_ieof(int type, int plen)
 }
 
 void
-channel_input_close(int type, int plen)
+channel_input_close(int type, int plen, void *ctxt)
 {
        int id;
        Channel *c;
@@ -1138,7 +1231,7 @@ channel_input_close(int type, int plen)
 
 /* 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);
@@ -1149,7 +1242,7 @@ channel_input_oclose(int type, int plen)
 }
 
 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);
@@ -1165,7 +1258,7 @@ channel_input_close_confirmation(int type, int plen)
 }
 
 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;
@@ -1189,9 +1282,9 @@ channel_input_open_confirmation(int type, int plen)
                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);
@@ -1199,7 +1292,7 @@ channel_input_open_confirmation(int type, int plen)
 }
 
 void
-channel_input_open_failure(int type, int plen)
+channel_input_open_failure(int type, int plen, void *ctxt)
 {
        int id;
        Channel *c;
@@ -1227,7 +1320,7 @@ channel_input_open_failure(int type, int plen)
 }
 
 void
-channel_input_channel_request(int type, int plen)
+channel_input_channel_request(int type, int plen, void *ctxt)
 {
        int id;
        Channel *c;
@@ -1240,19 +1333,19 @@ channel_input_channel_request(int type, int plen)
                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("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;
@@ -1271,7 +1364,7 @@ channel_input_window_adjust(int type, int plen)
        }
        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;
 }
 
@@ -1288,10 +1381,11 @@ channel_stop_listening()
                switch (channels[i].type) {
                case SSH_CHANNEL_AUTH_SOCKET:
                        close(channels[i].sock);
-                       remove(channels[i].path);
+                       unlink(channels[i].path);
                        channel_free(i);
                        break;
                case SSH_CHANNEL_PORT_LISTENER:
+               case SSH_CHANNEL_RPORT_LISTENER:
                case SSH_CHANNEL_X11_LISTENER:
                        close(channels[i].sock);
                        channel_free(i);
@@ -1335,8 +1429,10 @@ channel_still_open()
                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:
+               case SSH_CHANNEL_CONNECTING:    /* XXX ??? */
                        continue;
                case SSH_CHANNEL_LARVAL:
                        if (!compat20)
@@ -1380,11 +1476,13 @@ channel_open_message()
                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_OPEN:
                case SSH_CHANNEL_X11_OPEN:
                case SSH_CHANNEL_INPUT_DRAINING:
@@ -1412,19 +1510,44 @@ channel_open_message()
  * Initiate forwarding of connections to local port "port" through the secure
  * channel to host:port from remote side.
  */
+void
+channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
+    u_short port_to_connect, int gateway_ports)
+{
+       channel_request_forwarding(
+           NULL, listen_port,
+           host_to_connect, port_to_connect,
+           gateway_ports, /*remote_fwd*/ 0);
+}
 
+/*
+ * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
+ * (SSH_CHANNEL_RPORT_LISTENER).
+ */
 void
-channel_request_local_forwarding(u_short port, const char *host,
-                                u_short host_port, int gateway_ports)
+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;
+       int success, ch, sock, on = 1, ctype;
        struct addrinfo hints, *ai, *aitop;
        char ntop[NI_MAXHOST], strport[NI_MAXSERV];
+       const char *host;
        struct linger linger;
 
+       if (remote_fwd) {
+               host = listen_address;
+               ctype = SSH_CHANNEL_RPORT_LISTENER;
+       } else {
+               host = host_to_connect;
+               ctype  =SSH_CHANNEL_PORT_LISTENER;
+       }
+
        if (strlen(host) > sizeof(channels[0].path) - 1)
                packet_disconnect("Forward host name too long.");
 
+       /* 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
@@ -1433,7 +1556,7 @@ channel_request_local_forwarding(u_short port, const char *host,
        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");
 
@@ -1443,7 +1566,7 @@ channel_request_local_forwarding(u_short port, const char *host,
                        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. */
@@ -1481,18 +1604,16 @@ channel_request_local_forwarding(u_short port, const char *host,
                        continue;
                }
                /* Allocate a channel number for the socket. */
-               ch = channel_new(
-                   "port listener", SSH_CHANNEL_PORT_LISTENER,
-                   sock, sock, -1,
+               ch = channel_new("port listener", ctype, sock, sock, -1,
                    CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
-                   0, xstrdup("port listener"));
+                   0, xstrdup("port listener"), 1);
                strlcpy(channels[ch].path, host, sizeof(channels[ch].path));
-               channels[ch].host_port = host_port;
-               channels[ch].listening_port = port;
+               channels[ch].host_port = port_to_connect;
+               channels[ch].listening_port = listen_port;
                success = 1;
        }
        if (success == 0)
-               packet_disconnect("cannot listen port: %d", port);
+               packet_disconnect("cannot listen port: %d", listen_port);       /*XXX ?disconnect? */
        freeaddrinfo(aitop);
 }
 
@@ -1502,19 +1623,15 @@ channel_request_local_forwarding(u_short port, const char *host,
  */
 
 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";
@@ -1523,6 +1640,10 @@ channel_request_remote_forwarding(u_short listen_port, const char *host_to_conne
                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);
@@ -1530,11 +1651,27 @@ channel_request_remote_forwarding(u_short listen_port, const char *host_to_conne
                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++;
        }
 }
 
@@ -1555,6 +1692,7 @@ channel_input_port_forward_request(int is_root, int gateway_ports)
        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.
@@ -1562,9 +1700,8 @@ channel_input_port_forward_request(int is_root, int gateway_ports)
        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. */
@@ -1602,8 +1739,11 @@ channel_connect_to(const char *host, u_short host_port)
                        error("socket: %.100s", strerror(errno));
                        continue;
                }
+               if (fcntl(sock, F_SETFL, O_NDELAY) < 0)
+                       fatal("connect_to: F_SETFL: %s", strerror(errno));
                /* Connect to the host/port. */
-               if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
+               if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
+                   errno != EINPROGRESS) {
                        error("connect %.100s port %s: %.100s", ntop, strport,
                            strerror(errno));
                        close(sock);
@@ -1620,6 +1760,19 @@ channel_connect_to(const char *host, u_short host_port)
        /* 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 channel_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;
+}
 
 /*
  * This is called after receiving PORT_OPEN message.  This attempts to
@@ -1628,7 +1781,7 @@ channel_connect_to(const char *host, u_short host_port)
  */
 
 void
-channel_input_port_open(int type, int plen)
+channel_input_port_open(int type, int plen, void *ctxt)
 {
        u_short host_port;
        char *host, *originator_string;
@@ -1676,7 +1829,9 @@ channel_input_port_open(int type, int plen)
        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);
+               newch = channel_allocate(SSH_CHANNEL_CONNECTING,
+                   sock, originator_string);
+/*XXX delay answer? */
                channels[newch].remote_id = remote_channel;
 
                packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
@@ -1728,11 +1883,12 @@ x11_create_display_inet(int screen_number, int x11_display_offset)
                                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;
                                }
                        }
@@ -1827,7 +1983,7 @@ x11_create_display_inet(int screen_number, int x11_display_offset)
                (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. */
@@ -1969,7 +2125,7 @@ x11_connect_display(void)
  */
 
 void
-x11_input_open(int type, int plen)
+x11_input_open(int type, int plen, void *ctxt)
 {
        int remote_channel, sock = 0, newch;
        char *remote_host;
@@ -2013,6 +2169,28 @@ x11_input_open(int type, int plen)
        }
 }
 
+/* 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();
+}
+
 /*
  * Requests forwarding of X11 connections, generates fake authentication
  * data, and enables authentication spoofing.
@@ -2107,7 +2285,7 @@ auth_get_socket_name()
 void
 cleanup_socket(void)
 {
-       remove(channel_forwarded_auth_socket_name);
+       unlink(channel_forwarded_auth_socket_name);
        rmdir(channel_forwarded_auth_socket_dir);
 }
 
@@ -2174,8 +2352,11 @@ auth_input_request_forwarding(struct passwd * pw)
                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"));
+       newch = channel_new("auth socket",
+           SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
+           CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
+           0, xstrdup("auth socket"), 1);
+
        strlcpy(channels[newch].path, channel_forwarded_auth_socket_name,
            sizeof(channels[newch].path));
        return 1;
@@ -2184,7 +2365,7 @@ auth_input_request_forwarding(struct passwd * pw)
 /* 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;
        char *dummyname;
@@ -2305,18 +2486,28 @@ channel_cancel_cleanup(int id)
        }
        c->dettach_user = NULL;
 }
+void   
+channel_register_filter(int id, channel_filter_fn *fn)
+{
+       Channel *c = channel_lookup(id);
+       if (c == NULL) {
+               log("channel_register_filter: %d: bad id", id);
+               return;
+       }
+       c->input_filter = fn;
+}
 
 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);
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