Git ask for SSH passphrase even if present in ssh-agent

问题

I use git with ssh-agent on a daily basis on my Mac and it works flawlessly. However, on my remote development server, I should miss something because I can't bypass the prompt for the SSH password when doing remote git operations.

Setup

1. The key is listed in the ssh-agent: ssh-add -L:

   ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCktk2+zRYGy0RdM6HJ8JFVPjiNknK7iN8ohdCGSX9fPQ.... 
   /home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket
   

2. The key is associated to bitbucket in ~/.ssh/config:

   Host *
       IdentitiesOnly yes
       ServerAliveInterval 600
       ServerAliveCountMax 5
       TCPKeepAlive no
       IdentitiesOnly yes
   
   
   Host bitbucket bitbucket.org
      User git
      Hostname bitbucket.org
      KexAlgorithms diffie-hellman-group1-sha1
      Identityfile  /home/user/.ssh/id_rsa.user@server_to_git@bitbucket
   

3. Environment variables export | grep SSH_A:

   SSH_AGENT_PID=30294
   SSH_AUTH_SOCK=/tmp/ssh-IS3rVQtFwDxF/agent.30292
   

4. Agent is running ps -e | grep -q ssh-agent && echo "SSH Agent is running" returns

   SSH Agent is running
   

5. Permissions ls -al ~/.ssh:

   total 48K
   drwx------  2 user user 4,0K oct.  30 18:22 .
   drwxr-xr-x 18 user user 4,0K nov.   7 11:52 ..
   -rw-------  1 user user  431 mai   10  2016 authorized_keys
   lrwxrwxrwx  1 user user   62 oct.  30 16:50 config -> /home/user/.dotfiles/machine-specific/base/ssh/config
   -rw-------  1 user user  134 mars  26  2017 environment-
   -rw-------  1 user user  137 nov.   7 11:22 environment-server
   -rw-------  1 user user 1,8K mai   16 13:38 id_rsa.from_user@server_to_git@bitbucket
   -rw-r--r--  1 user user 2,6K oct.  30 11:02 known_hosts
   

6. My "hardened" /etc/ssh/ssh_config:

   AddressFamily inet
   BatchMode no
   CheckHostIP yes
   Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
   Compression yes
   ForwardAgent no
   ForwardX11 no
   GSSAPIAuthentication no
   GSSAPIDelegateCredentials no
   Host *
       HashKnownHosts yes
       SendEnv LANG LC_*
   HostbasedAuthentication no
   KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
   MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-ripemd160-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,hmac-ripemd160
   PasswordAuthentication no
   PermitLocalCommand no
   Port 22
   Protocol 2
   RSAAuthentication yes
   RhostsRSAAuthentication no
   StrictHostKeyChecking ask
   Tunnel no
   

However

1. Running git clone bitbucket:team/project.git returns

   Enter passphrase for key '/home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket':
   

Debug

1. Result ssh -v bitbucket:

   OpenSSH_6.6.1, OpenSSL 1.0.1f 6 Jan 2014
   debug1: Reading configuration data /home/user/.ssh/config
   debug1: /home/user/.ssh/config line 1: Applying options for *
   debug1: /home/user/.ssh/config line 10: Applying options for bitbucket
   debug1: Reading configuration data /etc/ssh/ssh_config
   debug1: /etc/ssh/ssh_config line 12: Applying options for *
   debug1: Hostname has changed; re-reading configuration
   debug1: Reading configuration data /home/user/.ssh/config
   debug1: /home/user/.ssh/config line 1: Applying options for *
   debug1: /home/user/.ssh/config line 10: Applying options for bitbucket.org
   debug1: Reading configuration data /etc/ssh/ssh_config
   debug1: /etc/ssh/ssh_config line 12: Applying options for *
   debug1: Connecting to bitbucket.org [104.192.143.2] port 22.
   debug1: Connection established.
   debug1: identity file /home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket type -1
   debug1: identity file /home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket-cert type -1
   debug1: identity file /home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket type -1
   debug1: identity file /home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket-cert type -1
   debug1: Enabling compatibility mode for protocol 2.0
   debug1: Local version string SSH-2.0-OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.8
   debug1: Remote protocol version 2.0, remote software version conker_1.0.314-df0526e app-132
   debug1: no match: conker_1.0.314-df0526e app-132
   debug1: SSH2_MSG_KEXINIT sent
   debug1: SSH2_MSG_KEXINIT received
   debug1: kex: server->client aes128-gcm@openssh.com <implicit> none
   debug1: kex: client->server aes128-gcm@openssh.com <implicit> none
   debug1: sending SSH2_MSG_KEXDH_INIT
   debug1: expecting SSH2_MSG_KEXDH_REPLY
   debug1: Server host key: RSA 97:8c:hidden:hidden:....
   debug1: Host 'bitbucket.org' is known and matches the RSA host key.
   debug1: Found key in /home/user/.ssh/known_hosts:1
   debug1: ssh_rsa_verify: signature correct
   debug1: SSH2_MSG_NEWKEYS sent
   debug1: expecting SSH2_MSG_NEWKEYS
   debug1: SSH2_MSG_NEWKEYS received
   debug1: SSH2_MSG_SERVICE_REQUEST sent
   debug1: SSH2_MSG_SERVICE_ACCEPT received
   debug1: Authentications that can continue: publickey
   debug1: Next authentication method: publickey
   debug1: Trying private key: /home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket
   debug1: key_parse_private2: missing begin marker
   debug1: key_parse_private_pem: PEM_read_PrivateKey failed
   debug1: read PEM private key done: type <unknown>
   Enter passphrase for key '/home/user/.ssh/id_rsa.from_user@server_to_git@bitbucket':
   

Any hint ?

回答1:

I just discovered that IdentitiesOnly needs the public key to be present on the local machine to works.

来源：https://stackoverflow.com/questions/47156229/git-ask-for-ssh-passphrase-even-if-present-in-ssh-agent