Paramiko TypeError：from_buffer无法返回str或unicode或bytearray对象内的原始字符串的地址

问题描述

我正在尝试使用Python和Paramiko连接到SFTP服务器，但出现此错误（当我使用pysftp时会发生相同的错误）：

starting thread (client mode): 0x17ccde50L
Local version/idstring: SSH-2.0-paramiko_2.7.2
Remote version/idstring: SSH-2.0-OpenSSH_7.2
Connected (version 2.0,client OpenSSH_7.2)
kex algos:[u'[e-mail]',u'ecdh-sha2-nistp256',u'ecdh-sha2-nistp384',u'ecdh-sha2-nistp521',u'diffie-hellman-group-exchange-sha256',u'diffie-hellman-group14-sha1'] server key:[u'ssh-rsa',u'rsa-sha2-512',u'rsa-sha2-256',u'ssh-dss',u'ecdsa-sha2-nistp256',u'ssh-ed25519'] client encrypt:[u'[e-mail]',u'aes128-ctr',u'aes192-ctr',u'aes256-ctr',u'[e-mail]',u'[e-mail]'] server encrypt:[u'[e-mail]',u'[e-mail]'] client mac:[u'[e-mail]',u'[e-mail]',u'[e-mail]',u'[e-mail]',u'[e-mail]',u'[e-mail]',u'[e-mail]',u'hmac-sha2-256',u'hmac-sha2-512',u'hmac-sha1'] server mac:[u'[e-mail]',u'hmac-sha1'] client compress:[u'none',u'[e-mail]'] server compress:[u'none',u'[e-mail]'] client lang:[u''] server lang:[u''] kex follows?False
Kex agreed: [e-mail]
HostKey agreed: ssh-ed25519
Cipher agreed: aes128-ctr
MAC agreed: hmac-sha2-256
Compression agreed: none
kex engine KexCurve25519 specified hash_algo <built-in function openssl_sha256>
UnkNown exception: from_buffer() cannot return the address of the raw string within a str or unicode or bytearray object
 Traceback (most recent call last):
   File "/usr/lib/python2.7/site-packages/paramiko/transport.py",line 2075,in run
     self.kex_engine.parse_next(ptype,m)
   File "/usr/lib/python2.7/site-packages/paramiko/kex_curve25519.py",line 64,in parse_next
     return self._parse_kexecdh_reply(m)
   File "/usr/lib/python2.7/site-packages/paramiko/kex_curve25519.py",line 129,in _parse_kexecdh_reply
     self.transport._activate_outbound()
   File "/usr/lib/python2.7/site-packages/paramiko/transport.py",line 2553,in _activate_outbound
     self.local_cipher,key_out,IV_out,self._ENCRYPT
   File "/usr/lib/python2.7/site-packages/paramiko/transport.py",line 1934,in _get_cipher
     return cipher.encryptor()
   File "/usr/lib64/python2.7/site-packages/cryptography/hazmat/primitives/ciphers/base.py",line 126,in encryptor
     self.algorithm,self.mode
   File "/usr/lib64/python2.7/site-packages/cryptography/hazmat/backends/openssl/backend.py",line 487,in create_symmetric_encryption_ctx
     return _CipherContext(self,cipher,mode,_CipherContext._ENCRYPT)
   File "/usr/lib64/python2.7/site-packages/cryptography/hazmat/backends/openssl/ciphers.py",line 69,in __init__
     iv_nonce = self._backend._ffi.from_buffer(mode.nonce)
 TypeError: from_buffer() cannot return the address of the raw string within a str or unicode or bytearray object

我能够使用以下方法成功连接到SFTP服务器：

sftp -oPort=22 xxxxx@10.132.x.x:/home

所以我知道服务器存在并且可以访问。

我在Python中的代码就是这样：

paramiko.util.log_to_file("filename.log")
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(
paramiko.AutoAddPolicy())
ssh.connect(ftp_host,username=ftp_username,password=ftp_password,timeout=None)

还有一些依赖项。

asn1crypto @ file:///home/folder/app/utils/asn1crypto-1.2.0-py2.py3-none-any.whl
bcrypt @ file:///home/folder/app/utils/bcrypt-3.1.6-cp27-cp27mu-manylinux1_x86_64.whl
cffi==1.5.2 
cryptography @ file:///home/folder/app/utils/cryptography-3.1-cp27-cp27mu-manylinux2010_x86_64.whl
netmiko==2.3.2
paramiko @ file:///home/folder/app/utils/vendor/paramiko-2.7.2-py2.py3-none-any.whl
ply==3.4
pyasn1==0.1.9
pycparser==2.19 
pynacl @ file:///home/folder/app/utils/pynacl-1.3.0-cp27-cp27mu-manylinux1_x86_64.whl
pyOpenSSL==16.0.0
six==1.9.0

我的问题是，该错误的确切含义是什么，解决该错误的最佳方法是什么？我需要将图像复制到SFTP，但无法完全连接。

顺便说一句，我正在运行Python的服务器卡在2.7上，并且我不允许对其进行升级。另外，它无法访问互联网，所以我不能使用apt-get之类的东西。我通过拖放压缩文件夹或.whl文件来安装东西。我只需要找到依赖关系的正确组合即可。

解决方法

本主题建议您可能具有过时的依赖项：
https://github.com/paramiko/paramiko/issues/1027

The solution by @bieli似乎可以帮助许多面临问题的人：

sudo pip uninstall cryptography -y && sudo apt-get purge python3-cryptography && sudo apt-get autoremove && sudo pip3 install --upgrade cryptography

---

如果无法升级依赖项，则可以尝试使用其他KEX。但总的来说，这可能是死路一条。

---

强制性警告：请勿使用AutoAddPolicy –这样做会失去对MITM attacks的保护。有关正确的解决方案，请参见Paramiko "Unknown Server" 。

,

在下面的示例中，您可能会看到一些依赖项的绝对路径，因为我正在没有Internet的远程服务器上运行Python脚本。因此，.whl文件必须从我的PC复制到远程服务器。在这些依赖项中，“ cffi ”已升级到1.11.2版，并最终解决了该问题。

如果发现自己遇到类似的问题，请尝试找到类似的最佳依赖项组合：

asn1crypto @ file:///home/badge_bridge/utils/asn1crypto-1.2.0-py2.py3-none-any.whl
bcrypt @ file:///home/badge_bridge/utils/bcrypt-3.1.6-cp27-cp27mu-manylinux1_x86_64.whl
cffi @ file:///home/badge_bridge/utils/vendor/cffi-1.11.2-cp27-cp27mu-manylinux1_x86_64.whl
chrome-gnome-shell==0.0.0
cryptography @ file:///home/badge_bridge/utils/vendor/cryptography-2.1-cp27-cp27mu-manylinux1_x86_64.whl
cupshelpers==1.0
ecdsa==0.6
enum34 @ file:///home/badge_bridge/utils/vendor/enum34-1.1.6-py2-none-any.whl
idna==2.0
ipaddress==1.0.14
isc==2.0
netmiko==2.3.2
paramiko @ file:///home/badge_bridge/utils/vendor/paramiko-2.3.3-py2.py3-none-any.whl
ply==3.4
pyasn1==0.1.9
pycparser==2.19
pycryptodome @ file:///home/badge_bridge/utils/vendor/pycryptodome-3.6.5-cp27-cp27mu-manylinux1_x86_64.whl
pycups==1.9.66
pycurl==7.19.0
pygobject==3.20.1
PyNaCl @ file:///home/badge_bridge/utils/PyNaCl-1.3.0-cp27-cp27mu-manylinux1_x86_64.whl
pyOpenSSL==16.0.0
pysftp==0.2.9
pysmbc==1.0.13
requests==2.11.1
six==1.13.0