OpenSSH_8.3p1, OpenSSL 1.1.1f 31 Mar 2020

[Everett, Tom (Nokia - US/Westford)]

I have tried to add kex to config files but I am still unable to get this to work. It was working at one point but I did not back it up or write instructions because I thought I would never have to touch it again, until I did 😊

Need help establishing the recipe again. Any help would be appreciated.


$ cygcheck -c Cygwin
Cygwin Package Information
Package              Version        Status
cygwin               3.1.7-1        OK


SSH Results:

debug1: Local version string SSH-2.0-OpenSSH_8.3
debug1: Remote protocol version 2.0, remote software version LiteSSH
debug1: no match: LiteSSH
…
…
debug1: kex: algorithm: (no match)
Unable to negotiate with 10.0.3.6 port 22: no matching key exchange method found. Their offer: diffie-hellman-group14-sha1




$ ssh -Q kex
diffie-hellman-group1-sha1
diffie-hellman-group14-sha1
diffie-hellman-group14-sha256
diffie-hellman-group16-sha512
diffie-hellman-group18-sha512
diffie-hellman-group-exchange-sha1
diffie-hellman-group-exchange-sha256
ecdh-sha2-nistp256
ecdh-sha2-nistp384
ecdh-sha2-nistp521
curve25519-sha256
curve25519-sha256@libssh.org
sntrup4591761x25519-sha512@tinyssh.org

$ ssh admin@10.0.3.6
Connection reset by 10.0.3.6 port 22

Complete listing:
$ ssh -vv -oHostKeyAlgorithms=+ssh-dss -oStrictHostKeyChecking=no admin@10.0.3.6
OpenSSH_8.3p1, OpenSSL 1.1.1f  31 Mar 2020
debug2: resolve_canonicalize: hostname 10.0.3.6 is address
debug2: ssh_connect_direct
debug1: Connecting to 10.0.3.6 [10.0.3.6] port 22.
debug1: Connection established.
debug1: identity file /home/tester/.ssh/id_rsa type -1
debug1: identity file /home/tester/.ssh/id_rsa-cert type -1
debug1: identity file /home/tester/.ssh/id_dsa type -1
debug1: identity file /home/tester/.ssh/id_dsa-cert type -1
debug1: identity file /home/tester/.ssh/id_ecdsa type -1
debug1: identity file /home/tester/.ssh/id_ecdsa-cert type -1
debug1: identity file /home/tester/.ssh/id_ecdsa_sk type -1
debug1: identity file /home/tester/.ssh/id_ecdsa_sk-cert type -1
debug1: identity file /home/tester/.ssh/id_ed25519 type -1
debug1: identity file /home/tester/.ssh/id_ed25519-cert type -1
debug1: identity file /home/tester/.ssh/id_ed25519_sk type -1
debug1: identity file /home/tester/.ssh/id_ed25519_sk-cert type -1
debug1: identity file /home/tester/.ssh/id_xmss type -1
debug1: identity file /home/tester/.ssh/id_xmss-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_8.3
debug1: Remote protocol version 2.0, remote software version LiteSSH
debug1: no match: LiteSSH
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to 10.0.3.6:22 as 'admin'
debug1: SSH2_MSG_KEXINIT sent
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: 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,ssh-ed25519-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,ssh-ed25519,sk-ssh-ed25519@openssh.com,rsa-sha2-512,rsa-sha2-256,ssh-rsa,ssh-dss
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: diffie-hellman-group14-sha1
debug2: host key algorithms: ssh-rsa
debug2: ciphers ctos: aes256-ctr
debug2: ciphers stoc: aes256-ctr
debug2: MACs ctos: hmac-sha1
debug2: MACs stoc: hmac-sha1
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: (no match)
Unable to negotiate with 10.0.3.6 port 22: no matching key exchange method found. Their offer: diffie-hellman-group14-sha1

Thanks,

Thomas Everett
Nokia USA
1 Robbins Rd.
Westford, MA. 01886
1-978-320-3746
tom.everett@nokia.com<mailto:tom.everett@nokia.com>