ssh卡在SSH2_MSG_KEX_DH_GEX_REQUEST(1024 <7680 <8192)上发送

Question

我可以通过networkmanager和openconnect插件连接到vpn.但是当我连接到公司的服务器时,我得到了以下日志:

[root@XSign ssh]# ssh username@xxx -v
OpenSSH_7.1p1, OpenSSL 1.0.2d 9 Jul 2015
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Connecting to xxx [x.x.x.x] port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_rsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file /root/.ssh/id_ed25519-cert type -1
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_7.1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.3
debug1: match: OpenSSH_5.3 pat OpenSSH_5* compat 0x0c000000
debug1: Authenticating to xxx:22 as 'username'
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr umac-64@openssh.com none
debug1: kex: client->server aes128-ctr umac-64@openssh.com none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<3072<8192) sent

然后它被困在最后一行.
我在公司时可以连接到xxx服务器.
我可以通过家里的同一网络将此xxx服务器与我以前的笔记本电脑连接起来.
这两款笔记本电脑之间的区别在于软件版本.

谁知道我卡住了？

Answer 1

您的目标服务器似乎不支持现代 HMAC，只允许较旧的（可能不安全的）HMAC。因此，源计算机上的默认 SSH 客户端设置会阻止连接。

您可以根据具体情况覆盖它，例如：

ssh -m umac-64@openssh.com targetserver
ssh -m hmac-sha1 targetserver
ssh -m hmac-md5 targetserver

.

或者，正如上面@hacksign 所建议的，您可以通过取消注释以下行来永久允许使用（可能）不安全的 HMAC /etc/ssh/ssh_config：

MACs hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-ripemd160 

Answer 2

MACs hmac-md5,hmac-sha1,umac-64 @ openssh.com,hmac-ripemd160

在/ etc/ssh/ssh_config中的行上面的文档,解决了这个问题.