Ubuntu14.04 普通用户无法通过 sshkey 登陆

[fourstring]

如题。目前的基本情况是：

本地：

• OS:OS X 10.11.6
• 用户名:fourstring

服务器:

• OS:Ubuntu14.04 x64 LTS
• 用户名:git(想要建立 git 远程仓库)

我新建了 git 用户，然后在/home/git下建立.ssh目录，设置权限为git:git 0700，并在.ssh目录下运行ssh-keygen，生成公私钥，将公钥命名为authorized_keys，设置权限git:git 0600。将私钥复制回本地，本地建立 ssh 配置，并且授予私钥权限 0600 。

之后，尝试使用 ssh 命令连接服务器，连接被拒绝。

我做的几点排查：

• auth.log 没有任何验证失败信息
• /etc/ssh/sshd_config中已经设置了

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

• 确认各个文件权限完全正确
• git 用户没有加入 /sbin/nologin(测试用)
• 由于是 ubuntu 不存在 selinux
• root 用户可以正常登陆

运行ssh hexo(配置中的 Host 名) -vvv信息如下:

OpenSSH_6.9p1, LibreSSL 2.1.8
debug1: Reading configuration data /Users/fourstring/.ssh/config
debug1: /Users/fourstring/.ssh/config line 1: Applying options for hexo
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 21: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to xxx port xxx.
debug1: Connection established.
debug1: identity file /Users/fourstring/.ssh/hexo type 1
debug1: key_load_public: No such file or directory
debug1: identity file /Users/fourstring/.ssh/hexo-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.9
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.6
debug1: match: OpenSSH_6.6.1p1 Ubuntu-2ubuntu2.6 pat OpenSSH_6.6.1* compat 0x04000000
debug2: fd 3 setting O_NONBLOCK
debug1: Authenticating to xxx as 'git'
debug3: put_host_port: xxx
debug3: hostkeys_foreach: reading file "/Users/fourstring/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/fourstring/.ssh/known_hosts:22
debug3: load_hostkeys: loaded 1 keys from xxx
debug3: order_hostkeyalgs: prefer hostkeyalgs: [e-mail],[e-mail],[e-mail],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: [e-mail],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: [e-mail],[e-mail],[e-mail],ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],ssh-ed25519,ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: [e-mail],aes128-ctr,aes192-ctr,aes256-ctr,[e-mail],[e-mail],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[e-mail]
debug2: kex_parse_kexinit: [e-mail],aes128-ctr,aes192-ctr,aes256-ctr,[e-mail],[e-mail],arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[e-mail]
debug2: kex_parse_kexinit: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[e-mail],[e-mail],[e-mail],[e-mail],hmac-md5,hmac-ripemd160,[e-mail],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-sha1,[e-mail],[e-mail],[e-mail],[e-mail],hmac-md5,hmac-ripemd160,[e-mail],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[e-mail],zlib
debug2: kex_parse_kexinit: none,[e-mail],zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: [e-mail],ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss,ecdsa-sha2-nistp256,ssh-ed25519
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,[e-mail],[e-mail],[e-mail],aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[e-mail]
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,[e-mail],[e-mail],[e-mail],aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,[e-mail]
debug2: kex_parse_kexinit: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-md5,hmac-sha1,[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,[e-mail],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: [e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],[e-mail],hmac-md5,hmac-sha1,[e-mail],[e-mail],hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,[e-mail],hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,[e-mail]
debug2: kex_parse_kexinit: none,[e-mail]
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug1: kex: server->client [e-mail] <implicit> none
debug1: kex: client->server [e-mail] <implicit> none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:jGsXPrH3Cl2EWrBRzd4rr72jDeWKugYGPySGAMFL1mU
debug3: put_host_port: xxx
debug3: put_host_port: xxx
debug3: hostkeys_foreach: reading file "/Users/fourstring/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/fourstring/.ssh/known_hosts:22
debug3: load_hostkeys: loaded 1 keys from xxx
debug3: hostkeys_foreach: reading file "/Users/fourstring/.ssh/known_hosts"
debug3: record_hostkey: found key type ECDSA in file /Users/fourstring/.ssh/known_hosts:22
debug3: load_hostkeys: loaded 1 keys from xxx
debug1: Host 'xxx' is known and matches the ECDSA host key.
debug1: Found key in /Users/fourstring/.ssh/known_hosts:22
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /Users/fourstring/.ssh/hexo (0x7f9f3b013d70), explicit
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: /Users/fourstring/.ssh/hexo
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
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).

最离奇的是以我自己的了解，我竟然没有从中看出任何连接被拒绝的信息。。。

另外，查找资料说本地用户名须和远程要登陆的用户名一致，但我的实际体验中并非如此。我的root用户就是本地生成sshkey上传到服务器，可以正常登陆。而且从我描述的流程中，可以看出我是在服务器上生成的key然后下载到本地的。

还望各位大神不吝赐教，感谢！

[sopato]

看看 /var/log/auth.log 输出了什么信息给你，根据那个错误信息来检查排错一下呗。

[shenqi]

不知道。围观下，坐等其他人的回答。

我觉得是露珠描述不清楚。

[ipeony]

private key 没加载好？正常是启个 agent ，然后 ssh-add 吧

[finian]

1. 远程 sshd 改完配置重启了吗？
2. 本地私钥是这个 /Users/fourstring/.ssh/hexo 对吗？

[wweir]

对 $HOME 目录的权限也有要求，验了么？
之前搞 docker 把 /root 目录共享了一下，也是 ssh 方面出了一大堆问题

[fourstring]

@sopato auth.log 没有任何错误……而且我还运行过 tail -f /var/run/auth.log ，在连接失败时该日志没有任何变化

[fourstring]

@shenqi 您觉得是哪里描述不清楚呢？请指出

[crazycen]

.ssh 目录不需要手动建立，还有，确认你生成 key 的方式是否正确。这是最基本功能，也不可能会出问题！

[fourstring]

@ipeony .ssh 目录下 config 文件是用 IdentifyFile 选项加载 privatekey 么？如果是的话我应该没有配置错。
另外和能正常登陆的 root 用户的-vvv 比较了一下，好像就只有 debug 信息的最后几行，正常的是
debug2: we sent a publickey packet, wait for reply
之后就收到 auth succeed 的回复然后进入 shell

[fourstring]

@finian 实际上我没有改过配置，那个配置是默认就有的。我也尝试过重启 sshd ，没有效果。私钥是这个，没有出错。

[fourstring]

@wweir 我用的是 adduser 命令添加用户，自动建立了主目录，刚刚又去检查了一下，$HOME 的权限是正确的

[fourstring]

@crazycen 请问.ssh 目录不手动建立该如何建立呢？另外生成 key 的方式是不是运行 ssh-keygen 命令？

[crazycen]

http://blog.sina.com.cn/s/blog_a0e5bf2c01010h1x.html 参考吧！

[larsenlouis]

普通用户能用密码登录吗？普通用户的 Home 加密了？如果普通用户 home 目录加密，本机没有登录的情况下， Home 目录没有挂载，只能密码登录。而 root 用户的 home 目录不在加密的目录里。

[oxoxoxox]

远端 server 的 authorized_keys 权限设置为 644 试试看呢？

[fourstring]

@larsenlouis 密码可以登录。我用 adduser 命令添加的用户，应该不会自动加密吧？ root 是可以正常访问 git 用户的$home 目录的

[fourstring]

@oxoxoxox 这个刚刚尝试了一下，貌似并没有什么用。。。/var/run/auth.log 里也没有报权限错误

[larsenlouis]

@fourstring 加密 home 是安装 ubuntu 系统时选的，你看看 /etc/fstab 有没有 encryptfs 的载点， root 可以正常访问时用 ssh 还是服务器本地，当时服务器本地有没有普通用户登录？

[fourstring]

@larsenlouis 对，安装 ubuntu 的时候确实会送这个。问题是我是 VPS 啊。。。 root 用 ssh 可以正常访问的。我都进不去服务器本地- -

[larsenlouis]

@fourstring 有些供应商会在虚拟机的控制台上模拟本地终端，你用普通用户登录后用`w`命令看看有没有 tty 的 session