Unable to connect via SFTP

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Posts: 8
Joined: 30 Mar 2020

woot

FFS version 11.0 [Donation Edition]. Authenticating via the agent, excerpt from the sshd_config:
Protocol 2
 AddressFamily inet
 Compression delayed
 KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
 Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com
 MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com
 PubkeyAuthentication yes
 HostbasedAuthentication no
 PasswordAuthentication no
 PermitEmptyPasswords no
 ChallengeResponseAuthentication no
 KerberosAuthentication no
 GSSAPIAuthentication no
 IgnoreRhosts yes
 GatewayPorts no
 AllowTcpForwarding no
 X11Forwarding no
 UsePAM no
 Subsystem sftp internal-sftp

Error returned:
Cannot find the following folders:
sftp://XXX.XXX.XXX.XXX
 ___________________________________________
Cannot read file attributes of "sftp://XXX.XXX.XXX.XXX".
 LIBSSH2_ERROR_KEX_FAILURE: Unable to exchange encryption keys [libssh2_session_handshake]
Please update libssh2 so it can be used with the modern cypher-set.
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Posts: 7051
Joined: 9 Dec 2007

Zenju

libssh2 feature requests need to be reported here: https://github.com/libssh2/libssh2/issues
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Posts: 7051
Joined: 9 Dec 2007

Zenju

Looks like such a request already exists: https://github.com/libssh2/libssh2/issues/457
Posts: 8
Joined: 30 Mar 2020

woot

Are you building against v1.9? Might be worth updating.

Looking at its changelog:
     adds ECDSA keys and host key support when using OpenSSL
      adds ED25519 key and host key support when using OpenSSL 1.1.1
     adds explicit zeroing of sensitive data in memory
      adds additional bounds checks to network buffer reads
     fixed a small memory leak during the key exchange process
      fixed a possible memory leak of the ssh banner string
      fixed various small memory leaks in the backends
      fixed possible out of bounds read when parsing public keys from the server
      fixed possible out of bounds read when parsing invalid PEM files
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Zenju

Are you building against v1.9? woot, 09 Aug 2020, 09:45
Yes.
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woot

Are you building against v1.9? woot, 09 Aug 2020, 09:45
Yes. Zenju, 09 Aug 2020, 09:57
OK, waiting for v2.0 then...
Posts: 8
Joined: 30 Mar 2020

woot

https://github.com/libssh2/libssh2/pull/468 was merged into the master branch. Pending release...