的paramiko协议错误：希望的分组SSH_MSG_USERAUTH_REQUEST，得到SSH_MSG_SERVICE_REQUEST

Question

当我使用ssh命令来手动连接到主机，一切工作正常：

$ ssh -v [email protected] -p 10000 
OpenSSH_6.1p1, OpenSSL 1.0.1c 10 May 2012 
debug1: Reading configuration data /home/todd/.ssh/config 
debug1: Reading configuration data /etc/ssh/ssh_config 
debug1: Connecting to mycli.abc.com [mycli.abc.com] port 10000. 
debug1: Connection established. 
debug1: identity file /home/todd/.ssh/id_rsa type 1 
debug1: identity file /home/todd/.ssh/id_rsa-cert type -1 
debug1: identity file /home/todd/.ssh/id_dsa type -1 
debug1: identity file /home/todd/.ssh/id_dsa-cert type -1 
debug1: identity file /home/todd/.ssh/id_ecdsa type -1 
debug1: identity file /home/todd/.ssh/id_ecdsa-cert type -1 
debug1: Remote protocol version 2.0, remote software version SSHD-CORE-0.6.0 
debug1: no match: SSHD-CORE-0.6.0 
debug1: Enabling compatibility mode for protocol 2.0 
debug1: Local version string SSH-2.0-OpenSSH_6.1 
debug1: SSH2_MSG_KEXINIT sent 
debug1: SSH2_MSG_KEXINIT received 
debug1: kex: server->client aes128-cbc hmac-md5 none 
debug1: kex: client->server aes128-cbc hmac-md5 none 
debug1: sending SSH2_MSG_KEXDH_INIT 
debug1: expecting SSH2_MSG_KEXDH_REPLY 
debug1: Server host key: DSA 6f:2c:48:80:86:ff:69:99:28:c2:21:5b:02:d4:7f:63 
debug1: checking without port identifier 
The authenticity of host '[mycli.abc.com]:10000 ([mycli.abc.com]:10000)' can't be established. 
DSA key fingerprint is 6f:2c:48:80:86:ff:69:99:28:c2:21:5b:02:d4:7f:63. 
Are you sure you want to continue connecting (yes/no)? yes 
Warning: Permanently added '[mycli.abc.com]:10000' (DSA) to the list of known hosts. 
debug1: ssh_dss_verify: signature correct 
debug1: SSH2_MSG_NEWKEYS sent 
debug1: expecting SSH2_MSG_NEWKEYS 
debug1: SSH2_MSG_NEWKEYS received 
debug1: Roaming not allowed by server 
debug1: SSH2_MSG_SERVICE_REQUEST sent 
debug1: SSH2_MSG_SERVICE_ACCEPT received 
debug1: Authentications that can continue: password,publickey 
debug1: Next authentication method: publickey 
debug1: Offering RSA public key: /home/todd/.ssh/id_rsa 
debug1: Authentications that can continue: password,publickey 
debug1: Trying private key: /home/todd/.ssh/id_dsa 
debug1: Trying private key: /home/todd/.ssh/id_ecdsa 
debug1: Next authentication method: password 
[email protected]'s password: 
debug1: Authentication succeeded (password). 
Authenticated to mycli.abc.com ([mycli.abc.com]:10000). 
debug1: channel 0: new [client-session] 
debug1: Entering interactive session. 
debug1: No xauth program. 
Warning: No xauth data; using fake authentication data for X11 forwarding. 
debug1: Requesting X11 forwarding with authentication spoofing. 
X11 forwarding request failed on channel 0 
Cli> 

但随着的paramiko它总是失败：

DEBUG:paramiko.transport:starting thread (client mode): 0x22783e10L 
INFO:paramiko.transport:Connected (version 2.0, client SSHD-CORE-0.6.0) 
DEBUG:paramiko.transport:kex algos:['diffie-hellman-group1-sha1'] server key:['ssh-dss'] client encrypt:['aes128-cbc', '3des-cbc', 'blowfish-cbc'] server encrypt:['aes128-cbc', '3des-cbc', 'blowfish-cbc'] client mac:['hmac-md5', 'hmac-sha1', 'hmac-md5-96', 'hmac-sha1-96'] server mac:['hmac-md5', 'hmac-sha1', 'hmac-md5-96', 'hmac-sha1-96'] client compress:['none'] server compress:['none'] client lang:[''] server lang:[''] kex follows?False 
DEBUG:paramiko.transport:Ciphers agreed: local=aes128-cbc, remote=aes128-cbc 
DEBUG:paramiko.transport:using kex diffie-hellman-group1-sha1; server key type ssh-dss; cipher: local aes128-cbc, remote aes128-cbc; mac: local hmac-sha1, remote hmac-sha1; compression: local none, remote none 
DEBUG:paramiko.transport:Switch to new keys ... 
DEBUG:paramiko.transport:Adding ssh-dss host key for [mycli.abc.com]:10000: 6f2c488086ff699928c2215b02d47f63 
DEBUG:paramiko.transport:Trying discovered key d7ab335994d0e5c90f8886b515faff55 in /home/todd/.ssh/id_rsa 
DEBUG:paramiko.transport:userauth is OK 
INFO:paramiko.transport:Authentication (publickey) failed. 
INFO:paramiko.transport:Disconnect (code 2): Protocol error: expected packet SSH_MSG_USERAUTH_REQUEST, got SSH_MSG_SERVICE_REQUEST 
Traceback (most recent call last): 
    File "./mycli_test.py", line 13, in <module> 
    oc = MyCli(hostname=hostname, username=username, password=password) 
    File "/home/todd/devel/mylib/mycli.py", line 16, in __init__ 
    key_filename, timeout, allow_agent, look_for_keys, compress) 
    File "/usr/lib/python2.7/site-packages/paramiko/client.py", line 338, in connect 
    self._auth(username, password, pkey, key_filenames, allow_agent, look_for_keys) 
    File "/usr/lib/python2.7/site-packages/paramiko/client.py", line 519, in _auth 
    raise saved_exception 
paramiko.AuthenticationException: Authentication failed. 

该paramiko脚本：

#!/usr/bin/env python2 

import paramiko 

paramiko.common.logging.basicConfig(level=paramiko.common.DEBUG) 

ssh = paramiko.SSHClient() 
ssh.set_missing_host_key_policy(paramiko.MissingHostKeyPolicy()) 
ssh.connect(hostname='mycli.abc.com', port=10000, username='admin', password='abc123') 
i, o, e = ssh.exec_command('uname -a') 
print o.readlines() 
ssh.close() 

paramiko版本：1.9.0

为什么会抛出“协议错误：期望的包SSH_MSG_USERAUTH_REQUEST，得到SSH_MSG_SERVICE_REQUEST”错误？如何避免它？

Answer 1

TL; DR： 补充一点：allow_agent=False和/或look_for_keys=False您connect()电话。

对此做了一些研究，我得出结论认为，Paramiko SSH客户端的公钥验证并不总是适用于所有SSH服务器。我试图连接到思科ASA设备。错误日志的相关部分为：

DEBUG:paramiko.transport:Switch to new keys ... 
DEBUG:paramiko.transport:Trying SSH agent key 5d081d52f889f2c224606d6b2065606e 
DEBUG:paramiko.transport:userauth is OK 
DEBUG:paramiko.transport:Authentication type (publickey) not permitted. 
DEBUG:paramiko.transport:Allowed methods: ['password'] 
INFO:paramiko.transport:Disconnect (code 2): Protocol error: expected packet type 50, got 5 

请注意'Trying SSH agent key ...'部分？我不想那样，我想强制密码认证。如果OpenSSH交互式客户端或者从publickey优雅地恢复到密码，paramiko不会强制它使用用户/密码认证解决了我的问题，它可能适用于您。

我不知道这是一个paramiko错误还是SSH服务器上的错误。与OpenSSH服务器交谈时，Paramiko的确从公钥转为密码或键盘交互。