什么是 Vault
Vault 是一个基于身份的秘密和加密管理系统。秘密是您想要严格控制访问的任何内容，例如 API 加密密钥、密码和证书。 Vault 提供由身份验证和授权方法控制的加密服务。使用 Vault 的 UI、CLI 或 HTTP API，可以安全地存储和管理、严格控制（限制）和审核对机密和其他敏感数据的访问。
为什么需要 Vault
- 执行密码轮换策略很痛苦
- 掌握机密的员工离职后可能泄密或是恶意报复
- 开发者不小心把机密信息随着代码上传到公网的源码仓库造成泄密
- 管理多个系统的机密非常麻烦
- 需要将机密信息安全地加密后存储，但又不想将密钥暴露给应用程序，以防止应用程序被入侵后连带密钥一起泄漏
Vault 架构图
Vault 只暴漏了存储后端(Storage Backend) 和 API，其他部分都被保护起来了。Vault 并不信任后端存储，存放的都是密文。
安装
此处以 Mac 为例，其他平台参考官方文档Vault 安装向导
❯ brew tap hashicorp/tap
❯ brew install hashicorp/tap/vault启动 Vault(Dev 模式)
❯ vault server -dev
WARNING! dev mode is enabled! In this mode, Vault runs entirely in-memory
and starts unsealed with a single unseal key. The root token is already
authenticated to the CLI, so you can immediately begin using Vault.
You may need to set the following environment variables:
$ export VAULT_ADDR='http://127.0.0.1:8200'
The unseal key and root token are displayed below in case you want to
seal/unseal the Vault or re-authenticate.
Unseal Key: QNqS6xZOnJKsbcz60PThJE2O070F2+9b7LLrGGgI7os=
Root Token: hvs.IKbh5pTGI0Qn08G5QNJb4jPY
Development mode should NOT be used in production installations!查看服务状态
❯ vault status
Key Value
--- -----
Seal Type shamir
Initialized true
Sealed false
Total Shares 1
Threshold 1
Version 1.12.1
Build Date 2022-10-27T12:32:05Z
Storage Type inmem
Cluster Name vault-cluster-c5c1f8a4
Cluster ID 60514532-959b-9540-ea21-5d9c968a21ba
HA Enabled false写入第一个密码
❯ vault write kv/infini value=infinilabs
Success! Data written to: kv/infini如果报这个错误:
vault write kv/infini value=infinilabs
Error writing data to kv/cheng: Error making API request.URL: PUT http://127.0.0.1:8200/v1/kv/chengCode: 404. Errors:
- no handler for route 'kv/cheng'
是因为 kv 存储没有启动(不同版本默认初始设置不同)，执行:
❯ vault secrets enable kv读取一条数据
❯ vault read kv/infini
Key Value
--- -----
refresh_interval 768h
value labs使用 Consul 作为数据存储的 Backend
Vault 自身不存储数据，需要提供存储后台。 支持多种后台。
❯ brew tap hashicorp/tap
❯ brew install hashicorp/tap/consul启动 Consul
❯ consul agent -dev
==> Starting Consul agent...
Version: '1.14.1'
Build Date: '2022-11-21 16:56:07 +0000 UTC'
Node ID: '6d9bcfc4-60cf-5d9b-c4fa-764127a94af6'
Node name: 'ChengKai-MacBook.local'
Datacenter: 'dc1' (Segment: '<all>')
Server: true (Bootstrap: false)
Client Addr: [127.0.0.1] (HTTP: 8500, HTTPS: -1, gRPC: 8502, gRPC-TLS: 8503, DNS: 8600)
Cluster Addr: 127.0.0.1 (LAN: 8301, WAN: 8302)
Gossip Encryption: false
Auto-Encrypt-TLS: false
HTTPS TLS: Verify Incoming: false, Verify Outgoing: false, Min Version: TLSv1_2
gRPC TLS: Verify Incoming: false, Min Version: TLSv1_2
Internal RPC TLS: Verify Incoming: false, Verify Outgoing: false (Verify Hostname: false), Min Version: TLSv1_2
==> Log data will now stream in as it occurs:
2022-11-30T16:34:52.604+0800 [WARN] agent: Node name "ChengKai-MacBook.local" will not be discoverable via DNS due to invalid characters. Valid characters include all alpha-numerics and dashes.
2022-11-30T16:34:52.609+0800 [WARN] agent.auto_config: Node name "ChengKai-MacBook.local" will not be discoverable via DNS due to invalid characters. Valid characters include all alpha-numerics and dashes.
2022-11-30T16:34:52.613+0800 [INFO] agent.server.raft: initial configuration: index=1 servers="[{Suffrage:Voter ID:6d9bcfc4-60cf-5d9b-c4fa-764127a94af6 Address:127.0.0.1:8300}]"
2022-11-30T16:34:52.614+0800 [INFO] agent.server.raft: entering follower state: follower="Node at 127.0.0.1:8300 [Follower]" leader-address= leader-id=启动 Vault(生产模式)
创建配置文件，使用刚刚启动的 Consul 作为存储后台。
注意: 这种方式启动，为生产模式，需要手动配置和管理秘钥。
storage "consul"{
address = "127.0.0.1:8500"
path = "vault/"
}
listener "tcp"{
address = "127.0.0.1:8200"
tls_disable = 1
}执行命令，启动
❯ vault server -config=config.hcl
WARNING! mlock is not supported on this system! An mlockall(2)-like syscall to
prevent memory from being swapped to disk is not supported on this system. For
better security, only run Vault on systems where this call is supported. If
you are running Vault in a Docker container, provide the IPC_LOCK cap to the
container.
==> Vault server configuration:
Api Address: http://127.0.0.1:8200
Cgo: disabled
Cluster Address: https://127.0.0.1:8201
Go Version: go1.19.2
Listener 1: tcp (addr: "127.0.0.1:8200", cluster address: "127.0.0.1:8201", max_request_duration: "1m30s", max_request_size: "33554432", tls: "disabled")
Log Level: info
Mlock: supported: false, enabled: false
Recovery Mode: false
Storage: consul (HA available)
Version: Vault v1.12.1, built 2022-10-27T12:32:05Z
Version Sha: e34f8a14fb7a88af4640b09f3ddbb5646b946d9c
==> Vault server started! Log data will stream in below:
2022-11-30T16:42:59.995+0800 [INFO] proxy environment: http_proxy="" https_proxy="" no_proxy=""
2022-11-30T16:43:00.006+0800 [WARN] no `api_addr` value specified in config or in VAULT_API_ADDR; falling back to detection if possible, but this value should be manually set注意: 此时虽然服务启动了，但是 Vault 处于封印状态(sealed)， 不可用。
此时我们执行操作，会看到如下提示:
❯ vault read kv/cheng
Error reading kv/cheng: Error making API request.
URL: GET http://127.0.0.1:8200/v1/kv/cheng
Code: 503. Errors:
* Vault is sealed上面 Dev 模式启动的 Vault 实际上帮助我们自动地把创建主密钥、解封的步骤都完成了。生产模式，则需要手动配置后续步骤。
补充点小知识
- Vault 保存在 Backend 中的数据都是加密的
- Vault 密钥称为 Master Key 主密钥，Vault 默认使用 Shamir 算法，把主密钥切分成 M 份，管理员必须至少提供其中的 N 份才能还原出主密钥（这里的 M 和 N 都是可配置的，M>=N）理想状态下，我们必须把这 M 份密钥分配给公司内 M 个不同的人，只有在获取其中 N 个人的授权后，Vault 才可以成功解密主密钥。
Vault 初始化(生产模式)
注意看，接下来的步骤，会生成 5 个秘钥，一个 Root 用户的 Token。真实场景下，这 5 个秘钥会分配给 5 个不同的人员管理。 至少正确输入 3 个秘钥，才能解封 Vault。
热知识: Vault 每次启动/重启，都会进入封印状态，未解封时，几乎无法执行任何操作。
> vault operator init
Unseal Key 1: IDcHr5kT7hhgYKiDxF6Qlp2g11UVXNu+f5VX51+3jpeD
Unseal Key 2: dfjqn++KcqLDIDnBcE8B0fIvicI7T9TQCxBSI7b1oE12
Unseal Key 3: DaFtgnYsm0rTQcPpLTPaDTNW338BHhyhezct+ySTT45L
Unseal Key 4: Z1vmlLm/KBydeLrmVf9ELqlJoaUgwzNvzx6ddXttc4Nk
Unseal Key 5: x2lIwJiCz3lNqzBPzkryrnatfZT9mahj3yfW4qxT3eMZ
Initial Root Token: s.o7NjzR6qXEvJEwPYpmVFOt4P
Vault initialized with 5 key shares and a key threshold of 3. Please securely
distribute the key shares printed above. When the Vault is re-sealed,
restarted, or stopped, you must supply at least 3 of these keys to unseal it
before it can start servicing requests.
Vault does not store the generated master key. Without at least 3 keys to
reconstruct the master key, Vault will remain permanently sealed!
It is possible to generate new unseal keys, provided you have a quorum of
existing unseal keys shares. See "vault operator rekey" for more information.Vault 默认访问 https 的地址，所以如果执行初始化报如下错误:
Error authenticating: error looking up token: Get "https://127.0.0.1:8200/v1/auth/token/lookup-self": http: server gave HTTP response to HTTPS client
设置一下 Vault 地址即可，执行:
export VAULT_ADDR='http://127.0.0.1:8200'
查看 Vault 状态
此时 Vault 处于封印状态(Sealed 为 true)
❯ vault status
Key Value
--- -----
Seal Type shamir
Initialized true
Sealed true
Total Shares 5
Threshold 3
Unseal Progress 0/3
Unseal Nonce n/a
Version 1.9.2
Storage Type consul
HA Enabled true解封 Vault
使用需要 vault operator unseal 命令来执行解封。至少需要 3 个秘钥来解封。
❯ vault operator unseal IDcHr5kT7hhgYKiDxF6Qlp2g11UVXNu+f5VX51+3jpeD
Key Value
--- -----
Seal Type shamir
Initialized true
Sealed true
Total Shares 5
Threshold 3
Unseal Progress 1/3
Unseal Nonce 9eeaaa92-d673-51d3-b993-d3affe68b5a3
Version 1.9.2
Storage Type consul
HA Enabled true注意: 每次输入一个秘钥，会看到如上提示"Unseal Progress 1/3"。 但是，这里仅仅表示已经输入多少个秘钥，并不代表输入的秘钥都是正确的!!
如何使用 Vault 保存秘密
进入下一步之前，先来看看 Vault 提供了哪些措施，用来保护我们的秘密？
- 秘钥的保护机制: 秘钥被拆分成 5 份，至少正确输入 3 个才能解封。
- 策略控制(权限控制): 可以针对每个 Path 设置策略。
- 有效期: Vault 生成的每个令牌(Token)都有有效期。
开始前，我们先写入 2 条测试数据:
❯ vault write kv/infini value=infinilabs
Success! Data written to: kv/infini
❯ vault write kv/ck value=chengkai
Success! Data written to: kv/ck热知识:
"kv/infini" 是一个 Path(路径), 可以简单理解为数据库中的一个表。并不是 kv 数据库 当中的 key。你可以试试这样存数据并读取:
❯ vault write kv/infini ck=chengkai c=cheng k=kai
Success! Data written to: kv/infini
❯ vault read kv/infini
Key Value
--- -----
refresh_interval 768h
c cheng
ck chengkai
k kai制定策略
新建策略文件
输入以下内容
path "kv/infini" {
capabilities = ["read"]
}解释: 以上策略，是指在 infini 这个路径(path)下，具有只读权限。
创建策略
先登录已经解封的 Vault(使用初始化生成的 root token 登录)
❯ vault login s.o7NjzR6qXEvJEwPYpmVFOt4P
Success! You are now authenticated. The token information displayed below
is already stored in the token helper. You do NOT need to run "vault login"
again. Future Vault requests will automatically use this token.
Key Value
--- -----
token s.o7NjzR6qXEvJEwPYpmVFOt4P
token_accessor tKZyxkkFvrmhQeTsoDOogcoV
token_duration ∞
token_renewable false
token_policies ["root"]
identity_policies []
policies ["root"]❯ vault policy write infini-readonly policy.hcl
Success! Uploaded policy: infini-readonly"infini-readonly" 是策略的名称，这个可以自定义
生成 Token 并指定策略
生成对"kv/infini"具有只读权限的 Token, 执行:
❯ vault token create -policy="infini-readonly"
Key Value
--- -----
token s.bHzsfREs9MGirYO8yZ2TbAzq
token_accessor nPuAQzNTn28vMMUKcDu0mN8g
token_duration 768h
token_renewable true
token_policies ["infini-readonly" "default"]
identity_policies []
policies ["infini-readonly" "default"]此处生成了新的 Token: s.bHzsfREs9MGirYO8yZ2TbAzq， 有效期 768 小时(别拿计算器了，我算过了，32 天)
使用新生成的 Token 登录(别找退出操作了，直接再执行 login 即可):
❯ vault login s.bHzsfREs9MGirYO8yZ2TbAzq
Success! You are now authenticated. The token information displayed below
is already stored in the token helper. You do NOT need to run "vault login"
again. Future Vault requests will automatically use this token.
Key Value
--- -----
token s.bHzsfREs9MGirYO8yZ2TbAzq
token_accessor nPuAQzNTn28vMMUKcDu0mN8g
token_duration 767h56m19s
token_renewable true
token_policies ["infini-readonly" "default"]
identity_policies []
policies ["infini-readonly" "default"]验证新生成的 Token
尝试读 kv/infini 的秘密:
❯ vault read kv/infini
Key Value
--- -----
refresh_interval 768h
value infinilabsWow！成功读取！
试试写入操作
❯ vault write kv/infini value=c1
Error writing data to kv/cheng: Error making API request.
URL: PUT http://127.0.0.1:8200/v1/kv/infini
Code: 403. Errors:
* 1 error occurred:
* permission denied有个疑问，你说当前这个 Token，可以读取 kv/ck 的秘密吗?
❯ vault read kv/ck
Error reading kv/ck: Error making API request.
URL: GET http://127.0.0.1:8200/v1/kv/ck
Code: 403. Errors:
* 1 error occurred:
* permission denied啊欧! 不行~
OK, 到这里了，简单的对 Vault 做了个入门。 Vault 的功能点还有很多，去看看下面的文档吧~~
参考文档
- [1]: Vault 官方文档
- [2]: Vault 教程(中文)
- [3]: How To Securely Manage Secrets with HashiCorp Vault on Ubuntu 20.04