I've three independent hosts - imaginatively called A, B and C. Firewall rules dictate that A can be directly accessed from B, but not from C... A and B run the openssh sshd, and C is a terminal with a working X-Windows display. C has a ssh session opened with B which tunnels port 22 on C to 22 on A. Thereafter, it is possible to ssh to localhost on C and get a ssh connection to A, which in turn I successfully use to tunnel IMAP, SMTP, Squid - etc. I'd have expected to be able to tunnel X11 over this link from C to A - but it fails... I'm unclear if the reason for the failure is the additional tunnelling... Is this technique incompatible with X11 tunnelling? Is there a way to make it work with a reverse-tunnel or something like that? Am I barking up the wrong tree entirely?
-- HostC# echo $DISPLAY :0.0 HostC# cat .ssh/config ForwardX11 yes HostC# ssh localhost -X HostA# echo $DISPLAY HostA# exit HostC# ssh localhost -Y HostA# echo $DISPLAY HostA# exit HostC# -- If I use -v -v I get this output... Curiously I have /usr/X11R6/bin/xauth on HostC, but xauth in in /usr/bin on host A. -- HostC# ssh localhost -Y OpenSSH_4.3p2, OpenSSL 0.9.8b 04 May 2006 debug1: Reading configuration data /home/user/.ssh/config debug2: ssh_connect: needpriv 0 debug1: Connecting to localhost [127.0.0.1] port 22. debug1: Connection established. debug1: identity file /home/user/.ssh/identity type -1 debug1: identity file /home/user/.ssh/id_rsa type -1 debug2: key_type_from_name: unknown key type '-----BEGIN' debug2: key_type_from_name: unknown key type '-----END' debug1: identity file /home/user/.ssh/id_dsa type 2 debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3 debug1: match: OpenSSH_4.3 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_4.3 debug2: fd 4 setting O_NONBLOCK debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1 debug2: kex_parse_kexinit: ssh-rsa,ssh-dss debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,[EMAIL PROTECTED],aes128-ctr,aes192-ctr,aes256-ctr debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,[EMAIL PROTECTED],aes128-ctr,aes192-ctr,aes256-ctr debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,[EMAIL PROTECTED],hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,[EMAIL PROTECTED],aes128-ctr,aes192-ctr,aes256-ctr debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,[EMAIL PROTECTED],aes128-ctr,aes192-ctr,aes256-ctr debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,[EMAIL PROTECTED],hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,[EMAIL PROTECTED],hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: none,[EMAIL PROTECTED],zlib debug2: kex_parse_kexinit: none,[EMAIL PROTECTED],zlib debug2: kex_parse_kexinit: debug2: kex_parse_kexinit: debug2: kex_parse_kexinit: first_kex_follows 0 debug2: kex_parse_kexinit: reserved 0 debug2: kex_parse_kexinit: diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1 debug2: kex_parse_kexinit: ssh-rsa,ssh-dss debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,[EMAIL PROTECTED],aes128-ctr,aes192-ctr,aes256-ctr debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,arcfour128,arcfour256,arcfour,aes192-cbc,aes256-cbc,[EMAIL PROTECTED],aes128-ctr,aes192-ctr,aes256-ctr debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,[EMAIL PROTECTED],hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-ripemd160,[EMAIL PROTECTED],hmac-sha1-96,hmac-md5-96 debug2: kex_parse_kexinit: none,[EMAIL PROTECTED] debug2: kex_parse_kexinit: none,[EMAIL PROTECTED] debug2: kex_parse_kexinit: debug2: kex_parse_kexinit: debug2: kex_parse_kexinit: first_kex_follows 0 debug2: kex_parse_kexinit: reserved 0 debug2: mac_init: found hmac-md5 debug1: kex: server->client aes128-cbc hmac-md5 none debug2: mac_init: found hmac-md5 debug1: kex: client->server aes128-cbc hmac-md5 none debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP debug2: dh_gen_key: priv key bits set: 121/256 debug2: bits set: 483/1024 debug1: SSH2_MSG_KEX_DH_GEX_INIT sent debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY debug1: Host 'localhost' is known and matches the RSA host key. debug1: Found key in /home/user/.ssh/known_hosts:4 debug2: bits set: 540/1024 debug1: ssh_rsa_verify: signature correct debug2: kex_derive_keys debug2: set_newkeys: mode 1 debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug2: set_newkeys: mode 0 debug1: SSH2_MSG_NEWKEYS received debug1: SSH2_MSG_SERVICE_REQUEST sent debug2: service_accept: ssh-userauth debug1: SSH2_MSG_SERVICE_ACCEPT received debug2: key: /home/user/.ssh/identity (0x0) debug2: key: /home/user/.ssh/id_rsa (0x0) debug2: key: /home/user/.ssh/id_dsa (0x1002ac08) debug1: Authentications that can continue: publickey debug1: Next authentication method: publickey debug1: Trying private key: /home/user/.ssh/identity debug1: Trying private key: /home/user/.ssh/id_rsa debug1: Offering public key: /home/user/.ssh/id_dsa debug2: we sent a publickey packet, wait for reply debug1: Server accepts key: pkalg ssh-dss blen 432 debug2: input_userauth_pk_ok: fp a5:97:1e:c3:8b:72:0c:91:69:13:32:25:95:8b:8d:c7 debug1: read PEM private key done: type DSA debug1: Authentication succeeded (publickey). debug1: channel 0: new [client-session] debug2: channel 0: send open debug1: Entering interactive session. debug2: callback start debug2: x11_get_proto: /usr/X11R6/bin/xauth list :0.0 2>/dev/null debug1: Requesting X11 forwarding with authentication spoofing. debug2: channel 0: request x11-req confirm 0 debug2: client_session2_setup: id 0 debug2: channel 0: request pty-req confirm 0 debug2: channel 0: request shell confirm 0 debug2: fd 4 setting TCP_NODELAY debug2: callback done debug2: channel 0: open confirm rwindow 0 rmax 32768 debug2: channel 0: rcvd adjust 131072 -- -- gentoo-user@gentoo.org mailing list
