RSA 密钥未通过身份验证

Question

只是想在 Ubuntu 机器上进行 openSSH 的基本设置以进行远程工作。主要问题：RSA 密钥验证失败。ssh 确实可以使用密码进行身份验证，但我更愿意将其限制为仅允许 ssh 密钥进行身份验证。

请注意，我指的是台式机和笔记本电脑。台式机：充当服务器的机器。笔记本电脑：充当客户端的机器。

我尝试过的事情：

• 验证权限
• 重新生成密钥
• 使用 ssh-copy-id 和直接通过复制和粘贴传输公钥
• 不同的客户端机器
• 运行 restorecon -Rv ~/.ssh （尽管大多数帖子说这主要适用于 CentOS，也可以尝试一切）
• 以及导致这里的大量谷歌搜索

我可以考虑包括的相关内容是尝试在笔记本电脑上连接时的 -vvv、两台机器上 ~/.ssh 的权限、桌面上的 sshd_config、桌面上 var/log/auth.log 中的相关条目。显然，如果我可以包含任何其他内容可以帮助任何人解决此问题，我将很乐意提供相关信息。

这是尝试进行身份验证时的 -vvv：

?  /home/troy 
?  ssh -vvv -i .ssh/id_rsa lenny@xxx.xxx.xxx.229 -p xxx40
OpenSSH_7.4p1, OpenSSL 1.0.2k  26 Jan 2017
debug1: Reading configuration data /etc/ssh/ssh_config
debug2: resolving "xxx.xxx.xxx.229" port xxx40
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to xxx.xxx.xxx.229 [xxx.xxx.xxx.229] port xxx40.
debug1: Connection established.
debug1: identity file .ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file .ssh/id_rsa-cert type -1
debug1: identity file /home/troy/.ssh/id_rsa type 1
debug1: key_load_public: No such file or directory
debug1: identity file /home/troy/.ssh/id_rsa-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_7.2p2 Ubuntu-4ubuntu2.1
debug1: match: OpenSSH_7.2p2 Ubuntu-4ubuntu2.1 pat OpenSSH* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to xxx.xxx.xxx.229:xxx40 as 'lenny'
debug3: put_host_port: [xxx.xxx.xxx.229]:xxx40
debug3: hostkeys_foreach: reading file "/home/troy/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/troy/.ssh/known_hosts:5
debug3: load_hostkeys: loaded 1 keys from [xxx.xxx.xxx.229]:xxx40
debug3: order_hostkeyalgs: prefer hostkeyalgs: ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,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,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-group-exchange-sha1,diffie-hellman-group14-sha256,diffie-hellman-group14-sha1,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,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-ed25519,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,aes128-cbc,aes192-cbc,aes256-cbc
debug2: ciphers stoc: chacha20-poly1305@openssh.com,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,aes128-cbc,aes192-cbc,aes256-cbc
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@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha1
debug2: host key algorithms: ssh-rsa,rsa-sha2-512,rsa-sha2-256,ecdsa-sha2-nistp256,ssh-ed25519
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
debug2: compression stoc: none,zlib@openssh.com
debug2: languages ctos: 
debug2: languages stoc: 
debug2: first_kex_follows 0 
debug2: reserved 0 
debug1: kex: algorithm: curve25519-sha256@libssh.org
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
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: ecdsa-sha2-nistp256 SHA256:M57GEOh/5elIh2RU446bRCamJ21QosRFOYaYx8u5Za4
debug3: put_host_port: [xxx.xxx.xxx.229]:xxx40
debug3: put_host_port: [xxx.xxx.xxx.229]:xxx40
debug3: hostkeys_foreach: reading file "/home/troy/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/troy/.ssh/known_hosts:5
debug3: load_hostkeys: loaded 1 keys from [xxx.xxx.xxx.229]:xxx40
debug3: hostkeys_foreach: reading file "/home/troy/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /home/troy/.ssh/known_hosts:5
debug3: load_hostkeys: loaded 1 keys from [xxx.xxx.xxx.229]:xxx40
debug1: Host '[xxx.xxx.xxx.229]:xxx40' is known and matches the ECDSA host key.
debug1: Found key in /home/troy/.ssh/known_hosts:5
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: .ssh/id_rsa (0x55a0c58221f0), explicit, agent
debug2: key: /home/troy/.ssh/id_rsa (0x55a0c582fe00), agent
debug3: send packet: type 5
debug3: receive packet: type 7
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
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
debug3: start over, passed a different list publickey
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: Offering RSA public key: .ssh/id_rsa
debug3: send_pubkey_test
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
debug1: Offering RSA public key: /home/troy/.ssh/id_rsa
debug3: send_pubkey_test
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
debug2: we did not send a packet, disable method
debug1: No more authentication methods to try.
Permission denied (publickey).

这是桌面上的 ~/.ssh ：

lenny@Timubukuntu:~/.ssh$ ls -la
total 12
drwx------.  2 lenny lenny 4096 Feb 27 21:49 .
drwxr-x---. 21 lenny lenny 4096 Feb 27 22:16 ..
-rw-------.  1 lenny lenny 1146 Feb 27 20:35 authorized_keys

笔记本电脑上的 ~/.ssh ：

?  /home/troy/.ssh 
?  ls -la
total 20
drwx------  2 troy users 4096 Feb 27 21:53 .
drwx------ 30 troy users 4096 Feb 27 23:03 ..
-rw-------  1 troy users 1679 Feb 27 20:32 id_rsa
-rw-r--r--  1 troy users  394 Feb 27 20:32 id_rsa.pub
-rw-r--r--  1 troy users 1416 Feb 27 15:13 known_hosts

以及桌面上的 sshd_config：

lenny@Timubukuntu:/etc/ssh$ cat sshd_config
# Package generated configuration file
# See the sshd_config(5) manpage for details

# What ports, IPs and protocols we listen for
Port xxx40 
# 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 120
PermitRootLogin prohibit-password
StrictModes yes

RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile  home/lenny/.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 no

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

# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes

X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin 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

这是桌面上 /var/log/auth.log 中的相关信息：

Feb 27 22:52:31 Timubukuntu sshd[1901]: Connection closed by 67.20.206.135 port 36566 [preauth]

Answer 1

除了获得关键权限的用户之外，任何人都不能写入主目录。否则该文件将被忽略

尝试chown -R troy:troy /home/troy/

/另外我认为您在 sshd_config 的这一部分中缺少 a

AuthorizedKeysFile home/lenny/.ssh/authorized_keys

Answer 2

就我而言，问题出在不正确的 shell 执行上。

journalctl -f
....
Feb 25 11:45:54 59a02b89e0f6 sshd[]: User user not allowed because shell /usr/bin/env /bin/bash does not exist
....

更改该用户的 /etc/passwd 文件

vi /etc/passwd 
....
user:x:1000:1000::/home/user:/bin/bash
....