由于业务需求，以前账号管理混乱，所以很多人有生产服务器的 root 权限；所以目前需要一个能 SSH 登录线上服务器的工具，同时具有简单的审计功能。

为了解决以上问题我找到了 Teleport 这个功能强大的开源工具，Teleport 是一款简单易用的使用 Go 语言编写的开源堡垒机系统，具有小巧、易用的特点，支持 RDP/SSH/SFTP/Telnet 协议的远程连接和审计管理。

Teleport 不仅可以同时管理大量服务器还可以作为一个终端录制工具，它提供了一个直观的 Web 界面来显示终端，也就是说你可以在浏览器操作服务器，在浏览器录制、分享。

Teleport 官网： https://www.tp4a.com/

一、环境准备

目前准备了 3 台虚拟机，两台位于内网 NAT 之后，一台位于公网可以直接链接；使用时客户端通过工具连接到公网跳板机上，然后实现自动跳转到内网任意主机；并且具有相应的操作回放审计，通过宿主机账户限制用户权限

二、Teleport 工作模式

Teleport 工作时从宏观上看是以集群为单位，也就是说公网算作一个集群，内网算作另一个集群，内网集群通过 ssh 隧道保持跟公网的链接状态，同时内网机群允许公网集群用户连接，大体工作模式如下

三、搭建公网 Master

3.1、配置 Systemd

首先下载相关可执行文件并复制到 Path 目录下，然后创建一下配置目录等

wget https://github.com/gravitational/teleport/releases/download/v2.3.5/teleport-v2.3.5-linux-amd64-bin.tar.gztar -zxvf teleport-v2.3.5-linux-amd64-bin.tar.gzmv teleport/tctl teleport/teleport teleport/tsh /usr/local/binmkdir -p /etc/teleport /data/teleport

然后为了让服务后台运行创建一个 systemd service 配置文件

cat > /etc/systemd/system/teleport.service <<EOF[Unit]Description=Teleport SSH ServiceAfter=network.target[Service]Type=simpleRestart=alwaysExecStart=/usr/local/bin/teleport start -c /etc/teleport/teleport.yaml[Install]WantedBy=multi-user.targetEOF

3.2、配置 Teleport

Systemd 配置完成后，就需要写一个 Teleport 的配置文件来让 Teleport 启动，具体选项含义可以参考 官方文档；以下为我的配置样例

# By default, this file should be stored in /etc/teleport.yaml# This section of the configuration file applies to all teleport# services.teleport:    # nodename allows to assign an alternative name this node can be reached by.    # by default it's equal to hostname    nodename: mritd.master    # Data directory where Teleport keeps its data, like keys/users for    # authentication (if using the default BoltDB back-end)    data_dir: /data/teleport    # one-time invitation token used to join a cluster. it is not used on    # subsequent starts    auth_token: jYektagNTmhjv9Dh    # when running in multi-homed or NATed environments Teleport nodes need    # to know which IP it will be reachable at by other nodes    advertise_ip: 92.223.67.84    # list of auth servers in a cluster. you will have more than one auth server    # if you configure teleport auth to run in HA configuration    auth_servers:        - 0.0.0.0:3025        - 0.0.0.0:3025    # Teleport throttles all connections to avoid abuse. These settings allow    # you to adjust the default limits    connection_limits:        max_connections: 1000        max_users: 250    # Logging configuration. Possible output values are 'stdout', 'stderr' and    # 'syslog'. Possible severity values are INFO, WARN and ERROR (default).    log:        output: stdout        severity: INFO    # Type of storage used for keys. You need to configure this to use etcd    # backend if you want to run Teleport in HA configuration.    storage:        type: bolt    # Cipher algorithms that the server supports. This section only needs to be    # set if you want to override the defaults.    ciphers:      - aes128-ctr      - aes192-ctr      - aes256-ctr      - aes128-gcm@openssh.com      - arcfour256      - arcfour128    # Key exchange algorithms that the server supports. This section only needs    # to be set if you want to override the defaults.    kex_algos:      - curve25519-sha256@libssh.org      - ecdh-sha2-nistp256      - ecdh-sha2-nistp384      - ecdh-sha2-nistp521      - diffie-hellman-group14-sha1      - diffie-hellman-group1-sha1    # Message authentication code (MAC) algorithms that the server supports.    # This section only needs to be set if you want to override the defaults.    mac_algos:      - hmac-sha2-256-etm@openssh.com      - hmac-sha2-256      - hmac-sha1      - hmac-sha1-96# This section configures the 'auth service':auth_service:    # Turns 'auth' role on. Default is 'yes'    enabled: yes    authentication:        # default authentication type. possible values are 'local', 'oidc' and 'saml'        # only local authentication (Teleport's own user DB) is supported in the open        # source version        type: local        # second_factor can be off, otp, or u2f        second_factor: otp        # this section is used if second_factor is set to 'u2f'        #u2f:        #    # app_id must point to the URL of the Teleport Web UI (proxy) accessible        #    # by the end users        #    app_id: https://localhost:3080        #    # facets must list all proxy servers if there are more than one deployed        #    facets:        #    - https://localhost:3080    # IP and the port to bind to. Other Teleport nodes will be connecting to    # this port (AKA "Auth API" or "Cluster API") to validate client    # certificates    listen_addr: 0.0.0.0:3025    # Pre-defined tokens for adding new nodes to a cluster. Each token specifies    # the role a new node will be allowed to assume. The more secure way to    # add nodes is to use `ttl node add --ttl` command to generate auto-expiring    # tokens.    #    # We recommend to use tools like `pwgen` to generate sufficiently random    # tokens of 32+ byte length.    tokens:        - "proxy,node:jYektagNTmhjv9Dh"        - "auth:jYektagNTmhjv9Dh"    # Optional "cluster name" is needed when configuring trust between multiple    # auth servers. A cluster name is used as part of a signature in certificates    # generated by this CA.    #    # By default an automatically generated GUID is used.    #    # IMPORTANT: if you change cluster_name, it will invalidate all generated    # certificates and keys (may need to wipe out /var/lib/teleport directory)    cluster_name: "mritd"# This section configures the 'node service':ssh_service:    # Turns 'ssh' role on. Default is 'yes'    enabled: yes    # IP and the port for SSH service to bind to.    listen_addr: 0.0.0.0:3022    # See explanation of labels in "Labeling Nodes" section below    labels:        role: master    # List of the commands to periodically execute. Their output will be used as node labels.    # See "Labeling Nodes" section below for more information.    commands:    - name: arch             # this command will add a label like 'arch=x86_64' to a node      command: [uname, -p]      period: 1h0m0s    # enables reading ~/.tsh/environment before creating a session. by default    # set to false, can be set true here or as a command line flag.    permit_user_env: false# This section configures the 'proxy servie'proxy_service:    # Turns 'proxy' role on. Default is 'yes'    enabled: yes    # SSH forwarding/proxy address. Command line (CLI) clients always begin their    # SSH sessions by connecting to this port    listen_addr: 0.0.0.0:3023    # Reverse tunnel listening address. An auth server (CA) can establish an    # outbound (from behind the firewall) connection to this address.    # This will allow users of the outside CA to connect to behind-the-firewall    # nodes.    tunnel_listen_addr: 0.0.0.0:3024    # The HTTPS listen address to serve the Web UI and also to authenticate the    # command line (CLI) users via password+HOTP    web_listen_addr: 0.0.0.0:3080    # TLS certificate for the HTTPS connection. Configuring these properly is    # critical for Teleport security.    #https_key_file: /var/lib/teleport/webproxy_key.pem    #https_cert_file: /var/lib/teleport/webproxy_cert.pem

然后启动 Teleport 即可

systemctl enable teleportsystemctl start teleport

如果启动出现如下错误

error: Could not load host key: /etc/ssh/ssh_host_ecdsa_keyerror: Could not load host key: /etc/ssh/ssh_host_ed25519_key

请执行 ssh-keygen 命令自行生成相关秘钥

ssh-keygen -t ecdsa -f /etc/ssh/ssh_host_ecdsa_keyssh-keygen -t ed25519 -f /etc/ssh/ssh_host_ed25519_key

3.3、添加用户

公网这台 Teleport 将会作为主要的接入机器，所以在此节点内添加的用户将有权限登录所有集群，包括内网的另一个集群；所以为了方便以后操作先添加一个用户

# 添加一个用户名为 mritd 的用户，该用户在所有集群具有 root 用户权限tctl --config /etc/teleport/teleport.yaml users add mritd root

添加成功后会返回一个 OTP 认证初始化地址，浏览器访问后可以使用 Google 扫描 OTP 二维码从而在登录时增加一层 OTP 认证

访问该地址后初始化密码及 OTP

四、搭建内网 Master

内网搭建 Master 和公网类似，只不过为了安全将所有 0.0.0.0 的地址全部换成内网 IP 即可，以下为内网的配置信息

# By default, this file should be stored in /etc/teleport.yaml# This section of the configuration file applies to all teleport# services.teleport:    # nodename allows to assign an alternative name this node can be reached by.    # by default it's equal to hostname    nodename: mritd.test1    # Data directory where Teleport keeps its data, like keys/users for    # authentication (if using the default BoltDB back-end)    data_dir: /data/teleport    # one-time invitation token used to join a cluster. it is not used on    # subsequent starts    auth_token: jYektagNTmhjv9Dh    # when running in multi-homed or NATed environments Teleport nodes need    # to know which IP it will be reachable at by other nodes    advertise_ip: 172.16.0.80    # list of auth servers in a cluster. you will have more than one auth server    # if you configure teleport auth to run in HA configuration    auth_servers:        - 172.16.0.80:3025    # Teleport throttles all connections to avoid abuse. These settings allow    # you to adjust the default limits    connection_limits:        max_connections: 1000        max_users: 250    # Logging configuration. Possible output values are 'stdout', 'stderr' and    # 'syslog'. Possible severity values are INFO, WARN and ERROR (default).    log:        output: stdout        severity: INFO    # Type of storage used for keys. You need to configure this to use etcd    # backend if you want to run Teleport in HA configuration.    storage:        type: bolt    # Cipher algorithms that the server supports. This section only needs to be    # set if you want to override the defaults.     ciphers:      - aes128-ctr      - aes192-ctr      - aes256-ctr      - aes128-gcm@openssh.com      - arcfour256      - arcfour128    # Key exchange algorithms that the server supports. This section only needs    # to be set if you want to override the defaults.    kex_algos:      - curve25519-sha256@libssh.org      - ecdh-sha2-nistp256      - ecdh-sha2-nistp384      - ecdh-sha2-nistp521      - diffie-hellman-group14-sha1      - diffie-hellman-group1-sha1    # Message authentication code (MAC) algorithms that the server supports.    # This section only needs to be set if you want to override the defaults.    mac_algos:      - hmac-sha2-256-etm@openssh.com      - hmac-sha2-256      - hmac-sha1      - hmac-sha1-96# This section configures the 'auth service':auth_service:    # Turns 'auth' role on. Default is 'yes'    enabled: yes    authentication:        # default authentication type. possible values are 'local', 'oidc' and 'saml'        # only local authentication (Teleport's own user DB) is supported in the open        # source version        type: local        # second_factor can be off, otp, or u2f        second_factor: otp        # this section is used if second_factor is set to 'u2f'        #u2f:        #    # app_id must point to the URL of the Teleport Web UI (proxy) accessible        #    # by the end users        #    app_id: https://localhost:3080        #    # facets must list all proxy servers if there are more than one deployed        #    facets:        #    - https://localhost:3080    # IP and the port to bind to. Other Teleport nodes will be connecting to    # this port (AKA "Auth API" or "Cluster API") to validate client    # certificates    listen_addr: 172.16.0.80:3025    # Pre-defined tokens for adding new nodes to a cluster. Each token specifies    # the role a new node will be allowed to assume. The more secure way to    # add nodes is to use `ttl node add --ttl` command to generate auto-expiring    # tokens.    #    # We recommend to use tools like `pwgen` to generate sufficiently random    # tokens of 32+ byte length.    tokens:        - "proxy,node:jYektagNTmhjv9Dh"        - "auth:jYektagNTmhjv9Dh"    # Optional "cluster name" is needed when configuring trust between multiple    # auth servers. A cluster name is used as part of a signature in certificates    # generated by this CA.    #    # By default an automatically generated GUID is used.    #    # IMPORTANT: if you change cluster_name, it will invalidate all generated    # certificates and keys (may need to wipe out /var/lib/teleport directory)    cluster_name: "nat"# This section configures the 'node service':ssh_service:    # Turns 'ssh' role on. Default is 'yes'    enabled: yes    # IP and the port for SSH service to bind to.    listen_addr: 172.16.0.80:3022    # See explanation of labels in "Labeling Nodes" section below    labels:        role: master    # List of the commands to periodically execute. Their output will be used as node labels.    # See "Labeling Nodes" section below for more information.    commands:    - name: arch             # this command will add a label like 'arch=x86_64' to a node      command: [uname, -p]      period: 1h0m0s    # enables reading ~/.tsh/environment before creating a session. by default    # set to false, can be set true here or as a command line flag.    permit_user_env: false# This section configures the 'proxy servie'proxy_service:    # Turns 'proxy' role on. Default is 'yes'    enabled: yes    # SSH forwarding/proxy address. Command line (CLI) clients always begin their    # SSH sessions by connecting to this port    listen_addr: 172.16.0.80:3023    # Reverse tunnel listening address. An auth server (CA) can establish an    # outbound (from behind the firewall) connection to this address.    # This will allow users of the outside CA to connect to behind-the-firewall    # nodes.    tunnel_listen_addr: 172.16.0.80:3024    # The HTTPS listen address to serve the Web UI and also to authenticate the    # command line (CLI) users via password+HOTP    web_listen_addr: 172.16.0.80:3080    # TLS certificate for the HTTPS connection. Configuring these properly is    # critical for Teleport security.    #https_key_file: /var/lib/teleport/webproxy_key.pem    #https_cert_file: /var/lib/teleport/webproxy_cert.pem

配置完成后直接启动即可

systemctl enable teleportsystemctl start teleport

五、将内网集群链接至公网

上文已经讲过，Teleport 通过公网链接内网主机的方式是让内网集群向公网打通一条 ssh 隧道，然后再进行通讯；具体配置如下

5.1、公网 Master 开启授信集群

在公网 Master 增加 Token 配置，以允许持有该 Token 的其他内网集群连接到此，修改 /etc/teleport/teleport.yaml 增加一个 token 即可

tokens:    - "proxy,node:jYektagNTmhjv9Dh"    - "auth:jYektagNTmhjv9Dh"    - "trusted_cluster:xiomwWcrKinFw4Vs"

然后重启 Teleport

systemctl restart teleport

5.2、内网 Master 链接公网 Master

当公网集群开启了允许其他集群链接后，内网集群只需要创建配置进行连接即可，创建配置(cluster.yaml)如下

# cluster.yamlkind: trusted_clusterversion: v2metadata:  # the trusted cluster name MUST match the 'cluster_name' setting of the  # cluster  name: local_clusterspec:  # this field allows to create tunnels that are disabled, but can be enabled later.  enabled: true  # the token expected by the "main" cluster:  token: xiomwWcrKinFw4Vs  # the address in 'host:port' form of the reverse tunnel listening port on the  # "master" proxy server:  tunnel_addr: 92.223.67.84:3024  # the address in 'host:port' form of the web listening port on the  # "master" proxy server:  web_proxy_addr: 92.223.67.84:3080

执行以下命令使内网集群通过 ssh 隧道连接到公网集群

tctl --config /etc/teleport/teleport.yaml create /etc/teleport/cluster.yaml

注意，如果在启动公网和内网集群时没有指定受信的证书( https_cert_file、https_key_file )，那么默认 Teleport 将会生成一个自签名证书，此时在 create 受信集群时将会产生如下错误:

the trusted cluster uses misconfigured HTTP/TLS certificate

此时需要在 待添加集群(内网) 启动时增加 --insecure 参数，即 Systemd 配置修改如下

[Unit]Description=Teleport SSH ServiceAfter=network.target[Service]Type=simpleRestart=alwaysExecStart=/usr/local/bin/teleport start --insecure -c /etc/teleport/teleport.yaml[Install]WantedBy=multi-user.target

然后再进行 create 就不会报错。

六、添加其他节点

两台节点打通后，此时如果有其他机器则可以将其加入到对应集群中，以下以另一台内网机器为例

由于在主节点 auth_service 中已经预先指定了一个 static Token 用于其他节点加入( proxy,node:jYektagNTmhjv9Dh )，所以其他节点只需要使用这个 Token 加入即可，在另一台内网主机上修改 Systemd 配置如下，然后启动即可

[Unit]Description=Teleport SSH ServiceAfter=network.target[Service]Type=simpleRestart=alwaysExecStart=/usr/local/bin/teleport start --roles=node,proxy \                                        --token=jYektagNTmhjv9Dh \                                        --auth-server=172.16.0.80[Install]WantedBy=multi-user.target

此时在内网的 Master 上可以查看到 Node 已经加入

test1.node ➜ tctl --config /etc/teleport/teleport.yaml nodes lsHostname    UUID                                 Address          Labels----------- ------------------------------------ ---------------- -----------------------test2.node  abc786fe-9a60-4480-80f7-8edc20710e58 172.16.0.81:3022mritd.test1 be9080fb-bdba-4823-9fb6-294e0b0dcce3 172.16.0.80:3022 arch=x86_64,role=master

七、连接测试

7.1、Web 测试

Teleport 支持 Web 页面访问，直接访问 https://公网IP:3080，然后登陆即可，登陆后如下

通过 Cluster 选项可以切换不同集群，点击后面的用户名可以选择不同用户登录到不同主机(用户授权在添加用户时控制)，登陆成功后如下

通过 Teleport 进行的所有操作可以通过审计菜单进行操作回放

7.2、命令行测试

类 Uninx 系统下我们还是习惯使用终端登录，终端登录需要借助 Teleport 的命令行工具 tsh，tsh在下载的 release 压缩版中已经有了，具体使用文档请自行 help 和参考官方文档，以下为简单的使用示例

• 登录跳板机: 短时间内只需要登录一次即可，登录时需要输入密码及 OTP 口令

export TELEPORT_PROXY=92.223.67.84export TELEPORT_USER=mritdtsh login --insecure

• 登录主机: 完成上一步 login 后就可以免密码登录任意主机

# cluster 名字是上面设置的，在 web 界面也能看到tsh ssh --cluster nat root@test2.node

• 复制文件: 复制文件时不显示进度，并非卡死

tsh scp --cluster nat teleport-v2.3.5-linux-amd64-bin.tar.gz root@test2.node:/-> teleport-v2.3.5-linux-amd64-bin.tar.gz (16797035)

注：本文中使用的 Teleport 版本相对比较旧了，目前最新版本为 3.10。转载这篇文章主要是为了推荐这个优秀的工具，如果你需要使用新版本 Teleport，也可以直接参考官方文档进行部署：https://docs.tp4a.com/

来源：漠然的博客
原文：http://t.cn/AiNmMKsJ
题图：来自谷歌图片搜索 
版权：本文版权归原作者所有
投稿：欢迎投稿，投稿邮箱: editor@hi-linux.com

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