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+title="Legoの使い方メモ"
+date=2019-04-14
+publishdate=2019-04-14
+Description="Legoを用いたDNS経由でのSSL/TSL証明書取得について調べた内容をまとめました"
+image="https://live.staticflickr.com/2554/4156026735_6b97110206.jpg"
++++
+
+`lego`を用いてSSL/TSL証明書を取得する方法を説明します。ここではDNS認証でSSL/TSL証明書を取得する方法を説明します。
+
+## LegoとLet’s Encrypt
+`Let’s Encrypt`はSSL/TSL証明書を発行してくれるサービスです。
+
+SSL/TSL証明書を発行するにあたり、そのドメインの所有者が本当に手続きをしているのか本人確認の手続きをします。
+
+手続き方法には以下の方法があります。
+
+### HTTP認証
+ドメインの所有者であれば、そのドメインにアクセスした際に表示されるコンテンツを自由にできるはずですので、それを利用した認証方式です。
+
+
+sequenceDiagram
+ participant User
+ participant Web Server
+ participant Let’s Encrypt
+ participant DNS
+
+ Note over User, DNS: 1. Resolve Host Name
+ User ->> DNS: Add A/CNAME record
+
+ Note over User, DNS: 2. Start Listening (Port 80)
+ User ->> Web Server: Set up Web Server
+
+ Note over User, DNS: 3. Request SSL/TSL Certificate
+ User ->> Let’s Encrypt: Request
+ Let’s Encrypt ->> DNS: Name Resolution Request
+ DNS ->> Let’s Encrypt: Name Resolution Response
+ Let’s Encrypt ->> Web Server: HTTP Request (Port 80) via Internet
+ Web Server ->> Let’s Encrypt: HTTP Response (200)
+ Let’s Encrypt ->> User: SSL/TSL Certificate
+
+
+### DNS認証
+ドメインの所有者であれば、そのドメインのTXTレコードを自由に設定できるはずですので、それを利用した認証方式です。
+
+
+sequenceDiagram
+ participant User
+ participant Let’s Encrypt
+ participant DNS
+
+ Note over User, DNS: 1. Request SSL/TSL Certificate
+ User ->> Let’s Encrypt: Request
+ Let’s Encrypt ->> User: Return the key
+ Note over User, DNS: 2. Specify TXT record
+ User ->> DNS: Specify the key to the TXT record
+ Note over User, DNS: 3. Continue the Request Process
+ User ->> Let’s Encrypt: Request to continue
+ Let’s Encrypt ->> DNS: Check the TXT record
+ DNS ->> Let’s Encrypt: Return the TXT record
+ alt TXT record: valid
+ Let’s Encrypt ->> User: SSL/TSL Certificate
+ else TXT record: not valid
+ Let’s Encrypt ->> User: Failure Notice
+ end
+
+
+### ここまでのまとめ
+Legoはコマンドラインで`Let’s Encrypt`を用いてSSL/TSL証明書を発行するツールです。DNS認証にも対応しており、各種マネージドのDNSサービスを利用することで、自動的にTXTレコードを変更して、SSL/TSL証明書を取得することができます。
+
+
+sequenceDiagram
+ participant User
+ participant Lego
+ participant Let’s Encrypt
+ participant DNS
+
+ User ->> Lego: Request
+ Lego ->> Let’s Encrypt: Request
+ Let’s Encrypt ->> Lego: Return the key
+ Lego ->> DNS: Specify the key to the TXT record
+ note over Lego,DNS: Wait for TXT record to propagate
+ Lego ->> Let’s Encrypt: Request to continue
+ Let’s Encrypt ->> DNS: Check the TXT record
+ DNS ->> Let’s Encrypt: Return the TXT record
+ Let’s Encrypt ->> Lego: SSL/TSL Certificate
+ Lego ->> User: SSL/TSL Certificate
+
+
+この記事ではAWSのマネージドDNSサービス`route53`を利用して、SSL/TSL証明書を取得してみます。
+
+## Legoのインストール方法
+githubからダウンロードします。
+
+### ダウンロード
+```
+kazu634@ip-10-0-1-234% wget https://github.com/go-acme/lego/releases/download/v2.4.0/lego_v2.4.0_linux_amd64.t
+ar.gz
+--2019-03-31 04:33:09-- https://github.com/go-acme/lego/releases/download/v2.4.0/lego_v2.4.0_linux_amd64.tar.gz
+Resolving github.com (github.com)... 192.30.255.112, 192.30.255.113
+Connecting to github.com (github.com)|192.30.255.112|:443... connected.
+HTTP request sent, awaiting response... 302 Found
+Location: https://github-production-release-asset-2e65be.s3.amazonaws.com/37038121/00375780-500b-11e9-89db-d849ef1f49d0?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20190331%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20190331T043309Z&X-Amz-Expires=300&X-Amz-Signature=bd866b55d7db150708b3b6a778430195ae6e82653c58cd0fa30b72c5abcd04dd&X-Amz-SignedHeaders=host&actor_id=0&response-content-disposition=attachment%3B%20filename%3Dlego_v2.4.0_linux_amd64.tar.gz&response-content-type=application%2Foctet-stream [following]
+--2019-03-31 04:33:10-- https://github-production-release-asset-2e65be.s3.amazonaws.com/37038121/00375780-500b-11e9-89db-d849ef1f49d0?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWNJYAX4CSVEH53A%2F20190331%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20190331T043309Z&X-Amz-Expires=300&X-Amz-Signature=bd866b55d7db150708b3b6a778430195ae6e82653c58cd0fa30b72c5abcd04dd&X-Amz-SignedHeaders=host&actor_id=0&response-content-disposition=attachment%3B%20filename%3Dlego_v2.4.0_linux_amd64.tar.gz&response-content-type=application%2Foctet-stream
+Resolving github-production-release-asset-2e65be.s3.amazonaws.com (github-production-release-asset-2e65be.s3.amazonaws.com)... 52.216.17.224
+Connecting to github-production-release-asset-2e65be.s3.amazonaws.com (github-production-release-asset-2e65be.s3.amazonaws.com)|52.216.17.224|:443... connected.
+HTTP request sent, awaiting response... 200 OK
+Length: 8597077 (8.2M) [application/octet-stream]
+Saving to: ‘lego_v2.4.0_linux_amd64.tar.gz’
+
+lego_v2.4.0_linux_amd64.tar 100%[=========================================>] 8.20M 3.81MB/s in 2.2s
+
+2019-03-31 04:33:12 (3.81 MB/s) - ‘lego_v2.4.0_linux_amd64.tar.gz’ saved [8597077/8597077]
+```
+
+### 解凍
+```
+kazu634@ip-10-0-1-234% tar xvzf lego_v2.4.0_linux_amd64.tar.gz [~/works]
+CHANGELOG.md
+LICENSE
+lego
+kazu634@ip-10-0-1-234% ll [~/works]
+total 35M
+drwxr-xr-x 2 kazu634 kazu634 4.0K Mar 31 04:34 .
+drwxr-xr-x 14 kazu634 kazu634 4.0K Mar 31 04:34 ..
+-rw-rw-r-- 1 kazu634 kazu634 18K Mar 26 19:52 CHANGELOG.md
+-rwxrwxr-x 1 kazu634 kazu634 27M Mar 26 20:02 lego
+-rw-rw-r-- 1 kazu634 kazu634 8.2M Mar 26 20:06 lego_v2.4.0_linux_amd64.tar.gz
+-rw-rw-r-- 1 kazu634 kazu634 1.1K Mar 26 19:52 LICENSE
+```
+
+## 使い方
+ここでは`lego`の使い方を説明します。
+
+### 下準備
+各種環境変数を指定して利用します。
+
+- `AWS_ACCESS_KEY_ID`
+- `AWS_SECRET_ACCESS_KEY`
+- `AWS_HOSTED_ZONE_ID`
+- `AWS_REGION`
+
+コマンドラインのヘルプはこんな感じになります:
+
+```
+kazu634@ip-10-0-1-234% ./lego dnshelp
+Credentials for DNS providers must be passed through environment variables.
+
+To display the documentation for a DNS providers:
+
+ $ lego dnshelp -c code
+
+All DNS codes:
+ acme-dns, alidns, auroradns, azure, bluecat, cloudflare, cloudns, cloudxns, conoha, designate, digitalocean, dnsimple, dnsmadeeasy, dnspod, dode, dreamhost, duckdns, dyn, exec, exoscale, fastdns, gandi, gandiv5, gcloud, glesys, godaddy, hostingde, httpreq, iij, inwx, lightsail, linode, linodev4, manual, mydnsjp, namecheap, namedotcom, netcup, nifcloud, ns1, oraclecloud, otc, ovh, pdns, rackspace, rfc2136, route53, sakuracloud, selectel, stackpath, transip, vegadns, vscale, vultr, zoneee
+
+More information: https://go-acme.github.io/lego/dns
+```
+
+`route53`特有の注意事項はこちら:
+
+```
+kazu634@ip-10-0-1-234% ./lego dnshelp -c route53
+Configuration for Amazon Route 53.
+Code: 'route53'
+
+Credentials:
+ - "AWS_ACCESS_KEY_ID":
+ - "AWS_HOSTED_ZONE_ID":
+ - "AWS_REGION":
+ - "AWS_SECRET_ACCESS_KEY":
+
+Additional Configuration:
+ - "AWS_POLLING_INTERVAL": Time between DNS propagation check
+ - "AWS_PROPAGATION_TIMEOUT": Maximum waiting time for DNS propagation
+ - "AWS_TTL": The TTL of the TXT record used for the DNS challenge
+```
+
+### AWS_ACCESS_KYE_IDとAWS_SECRET_ACCESS_KEYの調べ方
+後で書く
+
+### AWS_HOSTED_ZONE_IDの調べ方
+`route53`で`Hosted Zone ID`の部分を調べます:
+
+
+
+### 証明書の取得
+
+```
+export AWS_ACCESS_KEY_ID="xxxx"
+export AWS_SECRET_ACCESS_KEY="yyyy"
+export AWS_HOSTED_ZONE_ID="zzzz"
+export AWS_REGION="ap-northeast-1"
+
+kazu634@ip-10-0-1-234% ./lego --dns route53 --domains
+lego.kazu634.com --email simoom634@yahoo.co.jp run
+2019/03/31 05:02:07 [INFO] [lego.kazu634.com] acme: Ob
+taining bundled SAN certificate
+2019/03/31 05:02:08 [INFO] [lego.kazu634.com] AuthURL:
+ https://acme-v02.api.letsencrypt.org/acme/authz/kT24l
+TOu3gbmepIH2vWudVjaxSTi8Q2Lu1y_BGlxD1E
+2019/03/31 05:02:08 [INFO] [lego.kazu634.com] acme: Co
+uld not find solver for: tls-alpn-01
+2019/03/31 05:02:08 [INFO] [lego.kazu634.com] acme: Co
+uld not find solver for: http-01
+2019/03/31 05:02:08 [INFO] [lego.kazu634.com] acme: us
+e dns-01 solver
+2019/03/31 05:02:08 [INFO] [lego.kazu634.com] acme: Pr
+eparing to solve DNS-01
+2019/03/31 05:02:09 [INFO] Wait for route53 [timeout:
+2m0s, interval: 4s]
+2019/03/31 05:02:42 [INFO] [lego.kazu634.com] acme: Tr
+ying to solve DNS-01
+2019/03/31 05:02:42 [INFO] [lego.kazu634.com] acme: Ch
+ecking DNS record propagation using [localhost:53 127.
+0.0.1:53]
+2019/03/31 05:02:42 [INFO] Wait for propagation [timeo
+ut: 2m0s, interval: 4s]
+2019/03/31 05:02:47 [INFO] [lego.kazu634.com] The serv
+er validated our request
+2019/03/31 05:02:47 [INFO] [lego.kazu634.com] acme: Cl
+eaning DNS-01 challenge
+2019/03/31 05:02:47 [INFO] Wait for route53 [timeout:
+2m0s, interval: 4s]
+2019/03/31 05:03:25 [INFO] [lego.kazu634.com] acme: Validations succeeded; requesting certificates
+2019/03/31 05:03:26 [INFO] [lego.kazu634.com] Server responded with a certificate.
+```
+
+
+### nginxで証明書を指定する
+以下のように証明書が取得されているはずです:
+
+```
+kazu634@ip-10-0-1-234% pwd
+/home/kazu634/works/.lego/certificates
+
+kazu634@ip-10-0-1-234% ll
+total 28K
+drwxr-xr-x 2 kazu634 kazu634 4.0K Mar 31 05:50 .
+drwxr-xr-x 4 kazu634 kazu634 4.0K Mar 31 04:59 ..
+-rwxr-xr-x 1 root root 3.3K Mar 31 05:14 lego.kazu634.com.crt
+-rwxr-xr-x 1 kazu634 kazu634 1.7K Mar 31 05:14 lego.kazu634.com.issuer.crt
+-rwxr-xr-x 1 kazu634 kazu634 237 Mar 31 05:14 lego.kazu634.com.json
+-rwxr-xr-x 1 root root 288 Mar 31 05:14 lego.kazu634.com.key
+```
+
+この場合、`nginx`には以下のように指定します:
+
+```
+ ssl_certificate /home/kazu634/works/.lego/certificates/lego.kazu634.com.crt;
+ ssl_certificate_key /home/kazu634/works/.lego/certificates/lego.kazu634.com.key;
+```
+
+### IISで利用する場合
+後で書く
+
+### ワイルドカード証明書が必要な場合
+`route53`側で以下のようにレコードを作成する:
+
+
+
+その後は通常通り、コマンドを実行します:
+
+```
+kazu634@ip-10-0-1-234% ./lego --dns route53 --domains "*.kazu634.com" --email simoom634@yahoo.co.jp run
+2019/03/31 06:26:23 [INFO] [*.kazu634.com] acme: Obtaining bundled SAN certificate
+2019/03/31 06:26:23 [INFO] [*.kazu634.com] AuthURL: https://acme-v02.api.letsencrypt.org/acme/authz/FSIRwOjEhpS6H5U0hV2OT-s1ez8qRlHFNmLZ3-0PNw8
+2019/03/31 06:26:23 [INFO] [*.kazu634.com] acme: use dns-01 solver
+2019/03/31 06:26:23 [INFO] [*.kazu634.com] acme: Preparing to solve DNS-01
+2019/03/31 06:26:24 [INFO] Wait for route53 [timeout: 2m0s, interval: 4s]
+2019/03/31 06:27:02 [INFO] [*.kazu634.com] acme: Trying to solve DNS-01
+2019/03/31 06:27:02 [INFO] [*.kazu634.com] acme: Checking DNS record propagation using [localhost:53 127.0.0.1:53]
+2019/03/31 06:27:02 [INFO] Wait for propagation [timeout: 2m0s, interval: 4s]
+2019/03/31 06:27:06 [INFO] [*.kazu634.com] The server validated our request
+2019/03/31 06:27:06 [INFO] [*.kazu634.com] acme: Cleaning DNS-01 challenge
+2019/03/31 06:27:07 [INFO] Wait for route53 [timeout: 2m0s, interval: 4s]
+2019/03/31 06:29:04 [INFO] [*.kazu634.com] acme: Obtaining bundled SAN certificate
+2019/03/31 06:29:05 [INFO] [*.kazu634.com] AuthURL: https://acme-v02.api.letsencrypt.org/acme/authz/FSIRwOjEhp2019/03/31 06:29:06 [INFO] [*.kazu634.com] Server responded with a certificate.
+```
+
+
+## 参考
+- [nginx-lego/nginx.conf at master · pavels/nginx-lego · GitHub](https://github.com/pavels/nginx-lego/blob/master/nginx.conf)
+- [Let's Encrypt で DNS-01を利用したSSL証明書の取得方法 - Qiita](https://qiita.com/madaran0805/items/20c4437005d48458dc4f)
+- [Free wildcard certs with Let's Encrypt & DNS auth ft. Route 53 | Varun Priolkar](https://varunpriolkar.com/2018/05/free-wildcard-certs-with-lets-encrypt-dns-auth-ft-route-53/)
+- [Issue Let's Encrypt certificate using AWS Route53](https://appscode.com/products/voyager/7.0.0/guides/certificate/dns/route53/)
+- [How to Import & Export SSL Certificates in IIS 7 | DigiCert](https://www.digicert.com/ssl-support/pfx-import-export-iis-7.htm)
+- [Importing & Exporting SSL Certificates In IIS 8 & IIS 8.5](https://www.digicert.com/ssl-support/pfx-import-export-iis-8.htm)
+- [IIS 10 Exporting/Importing SSL Certificates | digicert.com](https://www.digicert.com/ssl-support/certificate-pfx-file-export-import-iis-10.htm)
+