内容信任的委派

Docker 内容信任（DCT）中的委派允许您控制谁可以签名，谁不能签名镜像标记。委托将具有一对私有和公共委托密钥。一个代表团可以包含多对密钥和贡献者，以便 a）允许多个用户成为委托的一部分，以及 b）支持密钥轮换。

Docker Content Trust 中最重要的委派是。这被视为可信镜像标签的规范来源，并且没有 contributor 的密钥在此委托下，他们将无法对标签进行签名。targets/releases

幸运的是，在使用这些命令时，我们会自动初始化存储库，管理存储库密钥，并通过将协作者的密钥添加到委派中。$ docker trusttargets/releasesdocker trust signer add

配置 Docker 客户端

默认情况下，这些命令期望公证服务器 URL 为与 image 标记中指定的注册表 URL 相同（遵循与类似的逻辑）。使用 Docker Hub 或 DTR 时，公证人服务器 URL 与注册表 URL 相同。但是，对于自托管 environments 或 3rd party registry 中，您需要指定替代项公证服务器的 URL。这是通过以下方式完成的：$ docker trust$ docker push

$ export DOCKER_CONTENT_TRUST_SERVER=https://<URL>:<PORT>

如果不在自托管环境中导出此变量，您可能会看到错误如下：

$ docker trust signer add --key cert.pem jeff registry.example.com/admin/demo
Adding signer "jeff" to registry.example.com/admin/demo...
<...>
Error: trust data missing for remote repository registry.example.com/admin/demo or remote repository not found: timestamp key trust data unavailable.  Has a notary repository been initialized?

$ docker trust inspect registry.example.com/admin/demo --pretty
WARN[0000] Error while downloading remote metadata, using cached timestamp - this might not be the latest version available remotely
<...>

如果您已为公证服务器启用身份验证，或者正在使用 DTR，则需要登录在您可以将数据推送到 Notary 服务器之前。

$ docker login registry.example.com/user/repo
Username: admin
Password:

Login Succeeded

$ docker trust signer add --key cert.pem jeff registry.example.com/user/repo
Adding signer "jeff" to registry.example.com/user/repo...
Initializing signed repository for registry.example.com/user/repo...
Successfully initialized "registry.example.com/user/repo"
Successfully added signer: jeff to registry.example.com/user/repo

如果您不登录，您将看到：

$ docker trust signer add --key cert.pem jeff registry.example.com/user/repo
Adding signer "jeff" to registry.example.com/user/repo...
Initializing signed repository for registry.example.com/user/repo...
you are not authorized to perform this operation: server returned 401.

Failed to add signer to: registry.example.com/user/repo

配置 Notary 客户端

DCT 的一些更高级的功能需要 Notary CLI。要安装并且配置 Notary CLI：

下载客户端并确保它在您的路径上可用。
在创建配置文件，内容如下：~/.notary/config.json

{
  "trust_dir" : "~/.docker/trust",
  "remote_server": {
    "url": "https://registry.example.com",
    "root_ca": "../.docker/ca.pem"
  }
}

新创建的配置文件包含有关本地 Docker 信任数据和公证服务器 URL 的位置的信息。

有关如何在 Docker Content Trust 使用案例，请参阅此处的 Notary CLI 文档

创建委托密钥

添加第一个贡献者的先决条件是一对委托密钥。这些键可以使用生成方式在本地生成，生成方式为证书颁发机构。$ docker trust

使用 Docker Trust 生成密钥

Docker trust 具有用于委派密钥对的内置生成器。运行此命令将自动加载将委托私有密钥委托到本地 Docker 信任存储中。$ docker trust generate <name>

$ docker trust key generate jeff

Generating key for jeff...
Enter passphrase for new jeff key with ID 9deed25: 
Repeat passphrase for new jeff key with ID 9deed25: 
Successfully generated and loaded private key. Corresponding public key available: /home/ubuntu/Documents/mytrustdir/jeff.pub

手动生成密钥

如果您需要手动生成私有密钥（RSA 或 ECDSA）和 x509 证书，您可以使用本地工具，如 OpenSSL 或 cfssl 以及本地或公司范围的证书颁发机构。

以下是如何生成 2048 位 RSA 部分密钥（所有 RSA 密钥必须至少为 2048 位）：

$ openssl genrsa -out delegation.key 2048

Generating RSA private key, 2048 bit long modulus
....................................................+++
............+++
e is 65537 (0x10001)

它们应该保持私有，因为它用于对标签进行签名。delegation.key

然后，他们需要生成一个包含公钥的 x509 证书，即你需要从他们那里得到什么。以下是生成 CSR（证书签名请求）：

$ openssl req -new -sha256 -key delegation.key -out delegation.csr

然后，他们可以将其发送到您信任的任何 CA 以签署证书，或者他们可以自签名证书（在此示例中，创建一个有效期为 1 年）：

$ openssl x509 -req -sha256 -days 365 -in delegation.csr -signkey delegation.key -out delegation.crt

然后他们需要给你，无论是自签名还是签名由 CA 提供。delegation.crt

最后，您需要将私钥添加到本地 Docker 信任存储中。

$ docker trust key load delegation.key --name jeff

Loading key from "delegation.key"...
Enter passphrase for new jeff key with ID 8ae710e: 
Repeat passphrase for new jeff key with ID 8ae710e: 
Successfully imported key from delegation.key

查看本地委派密钥

为了列出已导入到本地 Docker 信任存储中的密钥，我们可以使用 Notary CLI。

$ notary key list

ROLE       GUN                          KEY ID                                                              LOCATION
----       ---                          ------                                                              --------
root                                    f6c6a4b00fefd8751f86194c7d87a3bede444540eb3378c4a11ce10852ab1f96    /home/ubuntu/.docker/trust/private
jeff                                    9deed251daa1aa6f9d5f9b752847647cf8d705da0763aa5467650d0987ed5306    /home/ubuntu/.docker/trust/private

在 Notary Server 中管理委托

使用将第一个委托添加到 Notary Server 时，我们会自动启动存储库的信任数据。这包括创建 notary target 和 snapshots 键，并将快照键轮换为由 Notary 服务器管理。有关这些密钥的更多信息，请参见此处$ docker trust

启动存储库时，您将需要本地公证规范根密钥。如果您之前没有启动过仓库，并且因此没有 Notary 根密钥，将为您创建一个。$ docker trust

重要
请务必保护和备份您的 Notary Canonical Root Key。

启动存储库

要将第一个密钥上传到委托，同时启动 repository 中，您可以使用命令。这将添加贡献者的公钥分配给委托，并创建一个第二个代表团。$ docker trust signer addtargets/releasestargets/<name>

对于 DCT，第二个委托的名称（在以下示例中）可帮助您跟踪密钥的所有者。在更多 Notary 附加委托的高级用例用于层次结构。jeff

$ docker trust signer add --key cert.pem jeff registry.example.com/admin/demo

Adding signer "jeff" to registry.example.com/admin/demo...
Initializing signed repository for registry.example.com/admin/demo...
Enter passphrase for root key with ID f6c6a4b: 
Enter passphrase for new repository key with ID b0014f8: 
Repeat passphrase for new repository key with ID b0014f8: 
Successfully initialized "registry.example.com/admin/demo"
Successfully added signer: jeff to registry.example.com/admin/demo

您可以查看每个存储库的哪些密钥已推送到 Notary 服务器使用命令。$ docker trust inspect

$ docker trust inspect --pretty registry.example.com/admin/demo

No signatures for registry.example.com/admin/demo


List of signers and their keys for registry.example.com/admin/demo

SIGNER              KEYS
jeff                1091060d7bfd

Administrative keys for registry.example.com/admin/demo

  Repository Key:	b0014f8e4863df2d028095b74efcb05d872c3591de0af06652944e310d96598d
  Root Key:	64d147e59e44870311dd2d80b9f7840039115ef3dfa5008127d769a5f657a5d7

您还可以使用 Notary CLI 列出委托和密钥。在这里你可以清楚地看到密钥已附加到和。targets/releasestargets/jeff

$ notary delegation list registry.example.com/admin/demo

ROLE                PATHS             KEY IDS                                                             THRESHOLD
----                -----             -------                                                             ---------
targets/jeff        "" <all paths>    1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1    1
                                          
targets/releases    "" <all paths>    1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1    1

添加其他签名者

Docker Trust 允许您为每个存储库配置多个委托，允许您管理委托的生命周期。添加额外的具有 collaborators 密钥的委托将再次添加到角色。$ docker trusttargets/release

请注意，您将需要存储库密钥的密码;这本来是在您首次启动存储库时配置。

$ docker trust signer add --key ben.pub ben registry.example.com/admin/demo

Adding signer "ben" to registry.example.com/admin/demo...
Enter passphrase for repository key with ID b0014f8: 
Successfully added signer: ben to registry.example.com/admin/demo

检查以证明现在有 2 个委托（Signer）。

$ docker trust inspect --pretty registry.example.com/admin/demo

No signatures for registry.example.com/admin/demo

List of signers and their keys for registry.example.com/admin/demo

SIGNER              KEYS
ben                 afa404703b25
jeff                1091060d7bfd

Administrative keys for registry.example.com/admin/demo

  Repository Key:	b0014f8e4863df2d028095b74efcb05d872c3591de0af06652944e310d96598d
  Root Key:	64d147e59e44870311dd2d80b9f7840039115ef3dfa5008127d769a5f657a5d7

向现有委托添加密钥

要支持密钥轮换和过期/停用密钥等操作，您可以发布每个委托多个贡献者密钥。这里唯一的先决条件是使在本例中，请确保您使用相同的 delegation name .Docker 信任将自动处理将此新密钥添加到 .jefftargets/releases

注意
您将需要存储库密钥的密码;这本来是在您首次启动存储库时配置。

$ docker trust signer add --key cert2.pem jeff registry.example.com/admin/demo

Adding signer "jeff" to registry.example.com/admin/demo...
Enter passphrase for repository key with ID b0014f8: 
Successfully added signer: jeff to registry.example.com/admin/demo

检查以证明委托（Signer）现在包含多个密钥 ID。

$ docker trust inspect --pretty registry.example.com/admin/demo

No signatures for registry.example.com/admin/demo


List of signers and their keys for registry.example.com/admin/demo

SIGNER              KEYS
jeff                1091060d7bfd, 5570b88df073

Administrative keys for registry.example.com/admin/demo

  Repository Key:	b0014f8e4863df2d028095b74efcb05d872c3591de0af06652944e310d96598d
  Root Key:	64d147e59e44870311dd2d80b9f7840039115ef3dfa5008127d769a5f657a5d7

删除委托

如果需要删除委托，包括附加到角色后，您可以使用命令。targets/releases$ docker trust signer remove

注意
由已删除的委托签名的标记将需要重新签名由活跃的代表团

$ docker trust signer remove ben registry.example.com/admin/demo
Removing signer "ben" from registry.example.com/admin/demo...
Enter passphrase for repository key with ID b0014f8: 
Successfully removed ben from registry.example.com/admin/demo

故障排除

如果您看到中没有可用键的错误，则将需要使用 before 添加其他委托重新签名镜像。targets/releasesdocker trust signer add
WARN[0000] role targets/releases has fewer keys than its threshold of 1; it will not be usable until keys are added to it
如果您已添加其他委托并看到错误消息中没有有效的签名，您将需要以使用 Notary CLI 对委派文件进行签名。targest/releasestargets/releases
WARN[0000] Error getting targets/releases: valid signatures did not meet threshold for targets/releases
使用命令$ notary witness
$ notary witness registry.example.com/admin/demo targets/releases --publish
有关该命令的更多信息，请参见此处$ notary witness

从委托中删除贡献者的密钥

作为委派轮换密钥的一部分，您可能希望删除单个 key 但保留委托。这可以通过 Notary CLI 完成。

请记住，您必须从两个角色中删除密钥以及特定于该签名者的角色。targets/releasestargets/<name>

我们需要从 Notary 服务器获取密钥 ID

$ notary delegation list registry.example.com/admin/demo

ROLE                PATHS             KEY IDS                                                             THRESHOLD
----                -----             -------                                                             ---------
targets/jeff        "" <all paths>    8fb597cbaf196f0781628b2f52bff6b3912e4e8075720378fda60d17232bbcf9    1
                                      1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1    
targets/releases    "" <all paths>    8fb597cbaf196f0781628b2f52bff6b3912e4e8075720378fda60d17232bbcf9    1
                                      1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1

从委托中删除targets/releases

$ notary delegation remove registry.example.com/admin/demo targets/releases 1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1 --publish

Auto-publishing changes to registry.example.com/admin/demo
Enter username: admin
Enter password: 
Enter passphrase for targets key with ID b0014f8: 
Successfully published changes for repository registry.example.com/admin/demo

从委托中删除targets/<name>

$ notary delegation remove registry.example.com/admin/demo targets/jeff 1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1 --publish

Removal of delegation role targets/jeff with keys [5570b88df0736c468493247a07e235e35cf3641270c944d0e9e8899922fc6f99], to repository "registry.example.com/admin/demo" staged for next publish.

Auto-publishing changes to registry.example.com/admin/demo
Enter username: admin    
Enter password: 
Enter passphrase for targets key with ID b0014f8: 
Successfully published changes for repository registry.example.com/admin/demo

检查剩余的委托列表

$ notary delegation list registry.example.com/admin/demo

ROLE                PATHS             KEY IDS                                                             THRESHOLD
----                -----             -------                                                             ---------
targets/jeff        "" <all paths>    8fb597cbaf196f0781628b2f52bff6b3912e4e8075720378fda60d17232bbcf9    1    
targets/releases    "" <all paths>    8fb597cbaf196f0781628b2f52bff6b3912e4e8075720378fda60d17232bbcf9    1

删除本地委托私钥

作为轮换委托密钥的一部分，您可能需要删除本地委托 key 中。这是通过 Notary CLI 完成的，使用命令。$ notary key remove

我们需要从本地 Docker Trust 存储中获取密钥 ID

$ notary key list

ROLE       GUN                          KEY ID                                                              LOCATION
----       ---                          ------                                                              --------
root                                    f6c6a4b00fefd8751f86194c7d87a3bede444540eb3378c4a11ce10852ab1f96    /home/ubuntu/.docker/trust/private
admin                                   8fb597cbaf196f0781628b2f52bff6b3912e4e8075720378fda60d17232bbcf9    /home/ubuntu/.docker/trust/private
jeff                                    1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1    /home/ubuntu/.docker/trust/private
targets    ...example.com/admin/demo    c819f2eda8fba2810ec6a7f95f051c90276c87fddfc3039058856fad061c009d    /home/ubuntu/.docker/trust/private

从本地 Docker Trust 存储中删除密钥

$ notary key remove 1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1

Are you sure you want to remove 1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1 (role jeff) from /home/ubuntu/.docker/trust/private?  (yes/no)  y

Deleted 1091060d7bfd938dfa5be703fa057974f9322a4faef6f580334f3d6df44c02d1 (role jeff) from /home/ubuntu/.docker/trust/private.

从仓库中删除所有信任数据

您可以从存储库中删除所有信任数据，包括 repository、target、 snapshot 和所有委托密钥。

这通常是容器注册表在特定存储库之前需要的可以删除。

$ notary delete registry.example.com/admin/demo --remote

Deleting trust data for repository registry.example.com/admin/demo
Enter username: admin
Enter password: 
Successfully deleted local and remote trust data for repository registry.example.com/admin/demo

$ docker trust inspect --pretty registry.example.com/admin/demo

No signatures or cannot access registry.example.com/admin/demo