SSHキーが機能しない

SSHキーが機能しない

サーバーの ssh キーに問題があります。接続しようとするたびに、次のメッセージが表示されます (パスワードを入力する代わりにキーを使用して認証したいのですが、その後もパスワードを求められます)。他の記事から理解したところ、秘密キーの認証が失敗したか何かでパスワードを求められているようです。実行したところ、ssh -vvv user@ip次のようになりました:

$ ssh -vvv user@ip
OpenSSH_7.4p1, OpenSSL 1.0.2k  26 Jan 2017
debug2: resolving "ip" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to ip [ip] port 22.
debug1: Connection established.
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_rsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /home/Aericio/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.4
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.7p1 Debian-5+deb8u3
debug1: match: OpenSSH_6.7p1 Debian-5+deb8u3 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to ip:22 as 'user'
debug3: hostkeys_foreach: reading file "/home/Aericio/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/Aericio/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from ip
debug3: order_hostkeyalgs: prefer hostkeyalgs: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
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,[email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,ext-info-c
debug2: host key algorithms: [email protected],[email protected],[email protected],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[email protected],[email protected],ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa
debug2: ciphers ctos: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc
debug2: ciphers stoc: [email protected],aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],aes128-cbc,aes192-cbc,aes256-cbc
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected],zlib
debug2: compression stoc: none,[email protected],zlib
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug2: peer server KEXINIT proposal
debug2: KEX algorithms: [email protected],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: host key algorithms: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ssh-ed25519
debug2: ciphers ctos: aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],[email protected]
debug2: ciphers stoc: aes128-ctr,aes192-ctr,aes256-ctr,[email protected],[email protected],[email protected]
debug2: MACs ctos: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: MACs stoc: [email protected],[email protected],[email protected],[email protected],[email protected],[email protected],[email protected],hmac-sha2-256,hmac-sha2-512,hmac-sha1
debug2: compression ctos: none,[email protected]
debug2: compression stoc: none,[email protected]
debug2: languages ctos:
debug2: languages stoc:
debug2: first_kex_follows 0
debug2: reserved 0
debug1: kex: algorithm: [email protected]
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: [email protected] MAC: <implicit> compression: none
debug1: kex: client->server cipher: [email protected] 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: ecdsa-sha2-nistp256 SHA256:hTCFRXSL6Pn2ahO8AzocQsLS+VZP26OnZm/WvOWqq1I
debug3: hostkeys_foreach: reading file "/home/Aericio/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/Aericio/.ssh/known_hosts:1
debug3: load_hostkeys: loaded 1 keys from ip
debug1: Host 'ip' is known and matches the ECDSA host key.
debug1: Found key in /home/Aericio/.ssh/known_hosts:1
debug3: send packet: type 21
debug2: set_newkeys: mode 1
debug1: rekey 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 after 134217728 blocks
debug2: key: /home/Aericio/.ssh/id_rsa (0x0)
debug2: key: /home/Aericio/.ssh/id_dsa (0x0)
debug2: key: /home/Aericio/.ssh/id_ecdsa (0x0)
debug2: key: /home/Aericio/.ssh/id_ed25519 (0x0)
debug3: send packet: type 5
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 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: /home/Aericio/.ssh/id_rsa
debug3: no such identity: /home/Aericio/.ssh/id_rsa: No such file or directory
debug1: Trying private key: /home/Aericio/.ssh/id_dsa
debug3: no such identity: /home/Aericio/.ssh/id_dsa: No such file or directory
debug1: Trying private key: /home/Aericio/.ssh/id_ecdsa
Enter passphrase for key '/home/Aericio/.ssh/id_ecdsa':
debug3: sign_and_send_pubkey: ECDSA SHA256:/nMfW17zQ9zoH1UCzlSmLWtN4Mh/ST62SE5sB9B7D24
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
debug1: Trying private key: /home/Aericio/.ssh/id_ed25519
debug3: no such identity: /home/Aericio/.ssh/id_ed25519: No such file or directory
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
user@ip's password:

sshd_config 内の私の設定ファイルは次のとおりです:

# Package generated configuration file
# See the sshd_config(5) manpage for details

# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
HostKey /etc/ssh/ssh_host_ecdsa_key
HostKey /etc/ssh/ssh_host_ed25519_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes

# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 1024

# Logging
SyslogFacility AUTH
LogLevel INFO

# Authentication:
LoginGraceTime 60
PermitRootLogin no
StrictModes yes

RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile %h/.ssh/authorized_keys

# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
IgnoreUserKnownHosts yes

# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no

# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no

# Change to no to disable tunnelled clear text passwords
PasswordAuthentication yes

# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

X11Forwarding no
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive no
#MaxStartups 10:30:60
#Banner /etc/issue.net

# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

Subsystem sftp /usr/lib/openssh/sftp-server

# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication.  Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes

私は他のことをしようとしていました。セットを無効にして「いいえ」にするとpasswordauthenticationpam次のように表示されます。

$ ssh user@ip
Enter passphrase for key '/home/Aericio/.ssh/id_ecdsa':
Permission denied (publickey).

参考までに: 私は ssh を使用するために cygwin64 を使用しています。ありがとうございます。

答え1

これはログ ファイルの関連部分です。

debug1: Trying private key: /home/Aericio/.ssh/id_ecdsa
Enter passphrase for key '/home/Aericio/.ssh/id_ecdsa':
debug3: sign_and_send_pubkey: ECDSA SHA256:/nMfW17zQ9zoH1UCzlSmLWtN4Mh/ST62SE5sB9B7D24
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 51

SSH は 1 つのキー ファイル (id_ecdsa) を検出し、パスワードを要求してから、それを宛先サーバーに中継しました。宛先サーバーはキーを信頼しなかったため、SSH は次の認証方法の使用に移行しました。

必要なのは、公開キーを宛先サーバーのファイルにコピーすることですauthorized_keys。最も簡単な方法は、次のようになります。

ssh-copy-id <user>@<destination server>

複数のキーがある場合や、コピーする特定のIDが1つある場合は、-i .ssh/id_ecdsa.pubコマンドに以下を追加できます。

関連情報