Hello, I am unable to login via SSH using key with an alternate users.
It only works as root user (using keys).
I have enabled 'Password authentication' via Luci on dropbear, then after it fail I am able to login with user password. Occurs I want to login via ssh key with other users then root.
This start occuring after upgrade to OpenWrt 21.02.1 r16325-88151b8303.
My previous version was 19.07.2
Router model: TP-Link Archer C7 v5 (Qualcomm Atheros QCA956X ver 1 rev 0)
Seems like Dropbear does not even chalange for a key while I attempt to connect with an alternate user.
Is there a way to increase Dropbear log level?
> Sat Jan 29 11:05:53 2022 authpriv.info dropbear[12969]: Child connection from 192.168.1.13:59013
> Sat Jan 29 11:06:04 2022 authpriv.notice dropbear[12969]: Password auth succeeded for 'zetto33' from 192.168.1.13:59013
> Sat Jan 29 11:06:04 2022 authpriv.info dropbear[13020]: Child connection from 192.168.1.13:59014
> Sat Jan 29 11:06:06 2022 authpriv.notice dropbear[13020]: Password auth succeeded for 'zetto33' from 192.168.1.13:59014
> Sat Jan 29 11:07:06 2022 authpriv.notice sudo: zetto33 : TTY=pts/1 ; PWD=/home/zetto33 ; USER=root ; COMMAND=/sbin/logread -e dropbear
> Sat Jan 29 11:08:45 2022 authpriv.info dropbear[13846]: Child connection from 192.168.1.13:59037
> Sat Jan 29 11:09:03 2022 authpriv.info dropbear[13846]: Exit before auth from <192.168.1.13:59037>: (user 'root', 2 fails): Exited normally
> Sat Jan 29 11:09:40 2022 authpriv.info dropbear[14117]: Child connection from 192.168.1.13:59055
> Sat Jan 29 11:09:54 2022 authpriv.notice dropbear[14117]: Pubkey auth succeeded for 'root' with key sha1!! ce:23:08:64:e4:b1:ce:5d:35:c0:e3:53:96:37:f5:99:b1:3f:45:84 from 192.168.1.13:59055
FROM Client with alternate user
> zetto33@minecraft:~/.ssh$ ssh -vvvv -i temp zetto33@192.168.1.1 -p 22
> OpenSSH_8.2p1 Ubuntu-4ubuntu0.3, OpenSSL 1.1.1f 31 Mar 2020
> debug1: Reading configuration data /etc/ssh/ssh_config
> debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files
> debug1: /etc/ssh/ssh_config line 21: Applying options for *
> debug2: resolve_canonicalize: hostname 192.168.1.1 is address
> debug2: ssh_connect_direct
> debug1: Connecting to 192.168.1.1 [192.168.1.1] port 22.
> debug1: Connection established.
> debug1: identity file temp type -1
> debug1: identity file temp-cert type -1
> debug1: Local version string SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.3
> debug1: Remote protocol version 2.0, remote software version dropbear
> debug1: no match: dropbear
> debug2: fd 3 setting O_NONBLOCK
> debug1: Authenticating to 192.168.1.1:22 as 'zetto33'
> debug3: put_host_port: [192.168.1.1]:22
> debug3: hostkeys_foreach: reading file "/home/zetto33/.ssh/known_hosts"
> debug3: record_hostkey: found key type ED25519 in file /home/zetto33/.ssh/known_hosts:1
> debug3: load_hostkeys: loaded 1 keys from [192.168.1.1]:22
> debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-ed25519-cert-v01@openssh.com,ssh-ed25519
> debug3: send packet: type 20
> debug1: SSH2_MSG_KEXINIT sent
> debug3: receive packet: type 20
> debug1: SSH2_MSG_KEXINIT received
> debug2: local client KEXINIT proposal
> debug2: KEX algorithms: curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256,ext-info-c
> debug2: host key algorithms: ssh-ed25519-cert-v01@openssh.com,ssh-ed25519,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,sk-ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,sk-ecdsa-sha2-nistp256@openssh.com,sk-ssh-ed25519@openssh.com,rsa-sha2-512,rsa-sha2-256,ssh-rsa
> debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
> debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
> debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
> debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
> debug2: compression ctos: none,zlib@openssh.com,zlib
> debug2: compression stoc: none,zlib@openssh.com,zlib
> debug2: languages ctos:
> debug2: languages stoc:
> debug2: first_kex_follows 0
> debug2: reserved 0
> debug2: peer server KEXINIT proposal
> debug2: KEX algorithms: curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,kexguess2@matt.ucc.asn.au
> debug2: host key algorithms: ssh-ed25519,rsa-sha2-256,ssh-rsa
> debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes256-ctr
> debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes256-ctr
> debug2: MACs ctos: hmac-sha1,hmac-sha2-256
> debug2: MACs stoc: hmac-sha1,hmac-sha2-256
> debug2: compression ctos: none
> debug2: compression stoc: none
> debug2: languages ctos:
> debug2: languages stoc:
> debug2: first_kex_follows 0
> debug2: reserved 0
> debug1: kex: algorithm: curve25519-sha256
> debug1: kex: host key algorithm: ssh-ed25519
> debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none
> debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none
> debug3: send packet: type 30
> debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
> debug3: receive packet: type 31
> debug1: Server host key: ssh-ed25519 SHA256:uf7rwV+uKCF0i8MMV6LaxPHVlMoiohujowpSr/N4iV4
> debug3: put_host_port: [192.168.1.1]:22
> debug3: put_host_port: [192.168.1.1]:22
> debug3: hostkeys_foreach: reading file "/home/zetto33/.ssh/known_hosts"
> debug3: record_hostkey: found key type ED25519 in file /home/zetto33/.ssh/known_hosts:1
> debug3: load_hostkeys: loaded 1 keys from [192.168.1.1]:22
> debug3: hostkeys_foreach: reading file "/home/zetto33/.ssh/known_hosts"
> debug3: record_hostkey: found key type ED25519 in file /home/zetto33/.ssh/known_hosts:1
> debug3: load_hostkeys: loaded 1 keys from [192.168.1.1]:22
> debug1: Host '[192.168.1.1]:22' is known and matches the ED25519 host key.
> debug1: Found key in /home/zetto33/.ssh/known_hosts:1
> debug3: send packet: type 21
> debug2: set_newkeys: mode 1
> debug1: rekey out after 134217728 blocks
> debug1: SSH2_MSG_NEWKEYS sent
> debug1: expecting SSH2_MSG_NEWKEYS
> debug3: receive packet: type 21
> debug1: SSH2_MSG_NEWKEYS received
> debug2: set_newkeys: mode 0
> debug1: rekey in after 134217728 blocks
> debug1: Will attempt key: temp explicit
> debug2: pubkey_prepare: done
> debug3: send packet: type 5
> debug3: receive packet: type 7
> debug1: SSH2_MSG_EXT_INFO received
> debug1: kex_input_ext_info: server-sig-algs=<ssh-ed25519,rsa-sha2-256,ssh-rsa>
> debug3: receive packet: type 6
> debug2: service_accept: ssh-userauth
> debug1: SSH2_MSG_SERVICE_ACCEPT received
> debug3: send packet: type 50
> debug3: receive packet: type 51
> debug1: Authentications that can continue: publickey,password
> debug3: start over, passed a different list publickey,password
> debug3: preferred gssapi-with-mic,publickey,keyboard-interactive,password
> debug3: authmethod_lookup publickey
> debug3: remaining preferred: keyboard-interactive,password
> debug3: authmethod_is_enabled publickey
> debug1: Next authentication method: publickey
> debug1: Trying private key: temp
> Enter passphrase for key 'temp':
> debug3: sign_and_send_pubkey: RSA SHA256:Rl4tj8MUeTCfMmXIBxWRLABRyVgjUvv5WWjfDxw+iqQ
> debug3: sign_and_send_pubkey: signing using rsa-sha2-256 SHA256:Rl4tj8MUeTCfMmXIBxWRLABRyVgjUvv5WWjfDxw+iqQ
> debug3: send packet: type 50
> debug2: we sent a publickey packet, wait for reply
> debug3: receive packet: type 51
> debug1: Authentications that can continue: publickey,password <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
> debug2: we did not send a packet, disable method
> debug3: authmethod_lookup password
> debug3: remaining preferred: ,password
> debug3: authmethod_is_enabled password
> debug1: Next authentication method: password
> zetto33@192.168.1.1's password:
I am able to login using password, no issues here.
ROOT user:
> zetto33@minecraft:~/.ssh$ ssh -vvvv -i temp root@192.168.1.1 -p 22
> OpenSSH_8.2p1 Ubuntu-4ubuntu0.3, OpenSSL 1.1.1f 31 Mar 2020
> debug1: Reading configuration data /etc/ssh/ssh_config
> debug1: /etc/ssh/ssh_config line 19: include /etc/ssh/ssh_config.d/*.conf matched no files
> debug1: /etc/ssh/ssh_config line 21: Applying options for *
> debug2: resolve_canonicalize: hostname 192.168.1.1 is address
> debug2: ssh_connect_direct
> debug1: Connecting to 192.168.1.1 [192.168.1.1] port 22.
> debug1: Connection established.
> debug1: identity file temp type -1
> debug1: identity file temp-cert type -1
> debug1: Local version string SSH-2.0-OpenSSH_8.2p1 Ubuntu-4ubuntu0.3
> debug1: Remote protocol version 2.0, remote software version dropbear
> debug1: no match: dropbear
> debug2: fd 3 setting O_NONBLOCK
> debug1: Authenticating to 192.168.1.1:22 as 'root'
> debug3: put_host_port: [192.168.1.1]:22
> debug3: hostkeys_foreach: reading file "/home/zetto33/.ssh/known_hosts"
> debug3: record_hostkey: found key type ED25519 in file /home/zetto33/.ssh/known_hosts:1
> debug3: load_hostkeys: loaded 1 keys from [192.168.1.1]:22
> debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-ed25519-cert-v01@openssh.com,ssh-ed25519
> debug3: send packet: type 20
> debug1: SSH2_MSG_KEXINIT sent
> debug3: receive packet: type 20
> debug1: SSH2_MSG_KEXINIT received
> debug2: local client KEXINIT proposal
> debug2: KEX algorithms: curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group14-sha256,ext-info-c
> debug2: host key algorithms: ssh-ed25519-cert-v01@openssh.com,ssh-ed25519,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,sk-ssh-ed25519-cert-v01@openssh.com,rsa-sha2-512-cert-v01@openssh.com,rsa-sha2-256-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,sk-ecdsa-sha2-nistp256@openssh.com,sk-ssh-ed25519@openssh.com,rsa-sha2-512,rsa-sha2-256,ssh-rsa
> debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
> debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com
> debug2: MACs ctos: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
> debug2: MACs stoc: umac-64-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha1-etm@openssh.com,umac-64@openssh.com,umac-128@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-sha1
> debug2: compression ctos: none,zlib@openssh.com,zlib
> debug2: compression stoc: none,zlib@openssh.com,zlib
> debug2: languages ctos:
> debug2: languages stoc:
> debug2: first_kex_follows 0
> debug2: reserved 0
> debug2: peer server KEXINIT proposal
> debug2: KEX algorithms: curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,kexguess2@matt.ucc.asn.au
> debug2: host key algorithms: ssh-ed25519,rsa-sha2-256,ssh-rsa
> debug2: ciphers ctos: chacha20-poly1305@openssh.com,aes128-ctr,aes256-ctr
> debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes256-ctr
> debug2: MACs ctos: hmac-sha1,hmac-sha2-256
> debug2: MACs stoc: hmac-sha1,hmac-sha2-256
> debug2: compression ctos: none
> debug2: compression stoc: none
> debug2: languages ctos:
> debug2: languages stoc:
> debug2: first_kex_follows 0
> debug2: reserved 0
> debug1: kex: algorithm: curve25519-sha256
> debug1: kex: host key algorithm: ssh-ed25519
> debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none
> debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none
> debug3: send packet: type 30
> debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
> debug3: receive packet: type 31
> debug1: Server host key: ssh-ed25519 SHA256:uf7rwV+uKCF0i8MMV6LaxPHVlMoiohujowpSr/N4iV4
> debug3: put_host_port: [192.168.1.1]:22
> debug3: put_host_port: [192.168.1.1]:22
> debug3: hostkeys_foreach: reading file "/home/zetto33/.ssh/known_hosts"
> debug3: record_hostkey: found key type ED25519 in file /home/zetto33/.ssh/known_hosts:1
> debug3: load_hostkeys: loaded 1 keys from [192.168.1.1]:22
> debug3: hostkeys_foreach: reading file "/home/zetto33/.ssh/known_hosts"
> debug3: record_hostkey: found key type ED25519 in file /home/zetto33/.ssh/known_hosts:1
> debug3: load_hostkeys: loaded 1 keys from [192.168.1.1]:22
> debug1: Host '[192.168.1.1]:22' is known and matches the ED25519 host key.
> debug1: Found key in /home/zetto33/.ssh/known_hosts:1
> debug3: send packet: type 21
> debug2: set_newkeys: mode 1
> debug1: rekey out after 134217728 blocks
> debug1: SSH2_MSG_NEWKEYS sent
> debug1: expecting SSH2_MSG_NEWKEYS
> debug3: receive packet: type 21
> debug1: SSH2_MSG_NEWKEYS received
> debug2: set_newkeys: mode 0
> debug1: rekey in after 134217728 blocks
> debug1: Will attempt key: temp explicit
> debug2: pubkey_prepare: done
> debug3: send packet: type 5
> debug3: receive packet: type 7
> debug1: SSH2_MSG_EXT_INFO received
> debug1: kex_input_ext_info: server-sig-algs=<ssh-ed25519,rsa-sha2-256,ssh-rsa>
> debug3: receive packet: type 6
> debug2: service_accept: ssh-userauth
> debug1: SSH2_MSG_SERVICE_ACCEPT received
> debug3: send packet: type 50
> debug3: receive packet: type 51
> debug1: Authentications that can continue: publickey,password
> debug3: start over, passed a different list publickey,password
> debug3: preferred gssapi-with-mic,publickey,keyboard-interactive,password
> debug3: authmethod_lookup publickey
> debug3: remaining preferred: keyboard-interactive,password
> debug3: authmethod_is_enabled publickey
> debug1: Next authentication method: publickey
> debug1: Trying private key: temp
> Enter passphrase for key 'temp':
> debug3: sign_and_send_pubkey: RSA SHA256:Rl4tj8MUeTCfMmXIBxWRLABRyVgjUvv5WWjfDxw+iqQ
> debug3: sign_and_send_pubkey: signing using rsa-sha2-256 SHA256:Rl4tj8MUeTCfMmXIBxWRLABRyVgjUvv5WWjfDxw+iqQ
> debug3: send packet: type 50
> debug2: we sent a publickey packet, wait for reply
> debug3: receive packet: type 52
> debug1: Authentication succeeded (publickey).
> Authenticated to 192.168.1.1 ([192.168.1.1]:22).
> debug1: channel 0: new [client-session]
> debug3: ssh_session2_open: channel_new: 0
> debug2: channel 0: send open
> debug3: send packet: type 90
> debug1: Entering interactive session.
> debug1: pledge: network
> debug3: receive packet: type 91
> debug2: channel_input_open_confirmation: channel 0: callback start
> debug2: fd 3 setting TCP_NODELAY
> debug3: ssh_packet_set_tos: set IP_TOS 0x10
> debug2: client_session2_setup: id 0
> debug2: channel 0: request pty-req confirm 1
> debug3: send packet: type 98
> debug1: Sending environment.
> debug3: Ignored env SHELL
> debug3: Ignored env DERBY_HOME
> debug3: Ignored env JAVA_HOME
> debug3: Ignored env PWD
> debug3: Ignored env LOGNAME
> debug3: Ignored env XDG_SESSION_TYPE
> debug3: Ignored env J2REDIR
> debug3: Ignored env MOTD_SHOWN
> debug3: Ignored env HOME
> debug1: Sending env LANG = en_US.UTF-8
> debug2: channel 0: request env confirm 0
> debug3: send packet: type 98
> debug3: Ignored env LS_COLORS
> debug3: Ignored env SSH_CONNECTION
> debug3: Ignored env LESSCLOSE
> debug3: Ignored env XDG_SESSION_CLASS
> debug3: Ignored env TERM
> debug3: Ignored env J2SDKDIR
> debug3: Ignored env LESSOPEN
> debug3: Ignored env USER
> debug3: Ignored env DISPLAY
> debug3: Ignored env SHLVL
> debug3: Ignored env XDG_SESSION_ID
> debug3: Ignored env XDG_RUNTIME_DIR
> debug3: Ignored env SSH_CLIENT
> debug3: Ignored env XDG_DATA_DIRS
> debug3: Ignored env PATH
> debug3: Ignored env DBUS_SESSION_BUS_ADDRESS
> debug3: Ignored env SSH_TTY
> debug3: Ignored env _
> debug3: Ignored env OLDPWD
> debug2: channel 0: request shell confirm 1
> debug3: send packet: type 98
> debug2: channel_input_open_confirmation: channel 0: callback done
> debug2: channel 0: open confirm rwindow 24576 rmax 32759
> debug3: receive packet: type 99
> debug2: channel_input_status_confirm: type 99 id 0
> debug2: PTY allocation request accepted on channel 0
> debug3: receive packet: type 99
> debug2: channel_input_status_confirm: type 99 id 0
> debug2: shell request accepted on channel 0
>
>
> BusyBox v1.33.1 (2021-10-24 09:01:35 UTC) built-in shell (ash)
>
> _______ ________ __
> | |.-----.-----.-----.| | | |.----.| |_
> | - || _ | -__| || | | || _|| _|
> |_______|| __|_____|__|__||________||__| |____|
> |__| W I R E L E S S F R E E D O M
> -----------------------------------------------------
> OpenWrt 21.02.1, r16325-88151b8303
> -----------------------------------------------------
> root@Archer:~# exit
> debug3: receive packet: type 96
> debug2: channel 0: rcvd eof
> debug2: channel 0: output open -> drain
> debug2: channel 0: obuf empty
> debug2: channel 0: chan_shutdown_write (i0 o1 sock -1 wfd 5 efd 6 [write])
> debug2: channel 0: output drain -> closed
> debug3: receive packet: type 98
> debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
> debug3: receive packet: type 97
> debug2: channel 0: rcvd close
> debug2: channel 0: chan_shutdown_read (i0 o3 sock -1 wfd 4 efd 6 [write])
> debug2: channel 0: input open -> closed
> debug3: channel 0: will not send data after close
> debug2: channel 0: almost dead
> debug2: channel 0: gc: notify user
> debug2: channel 0: gc: user detached
> debug2: channel 0: send close
> debug3: send packet: type 97
> debug2: channel 0: is dead
> debug2: channel 0: garbage collecting
> debug1: channel 0: free: client-session, nchannels 1
> debug3: channel 0: status: The following connections are open:
> #0 client-session (t4 r0 i3/0 o3/0 e[write]/0 fd -1/-1/6 sock -1 cc -1)
>
> debug3: send packet: type 1
> debug3: fd 1 is not O_NONBLOCK
> Connection to 192.168.1.1 closed.
> Transferred: sent 2872, received 1596 bytes, in 13.1 seconds
> Bytes per second: sent 218.9, received 121.6
> debug1: Exit status 0
Any help is appreciated!
P.S. I have attempt to change key file permission, but no success.
zetto33@Archer:~$ ls -la /etc/dropbear/
drwx------ 1 zetto33 root 0 Jan 29 09:15 .
drwxr-xr-x 1 root root 0 Jan 29 12:26 ..
**-rw------- 1 zetto33 root 389 Jan 29 11:04 authorized_keys**
-rw------- 1 root root 83 Jan 27 10:33 dropbear_ed25519_host_key
-rw------- 1 root root 805 Nov 5 2019 dropbear_rsa_host_key