cfssl 证书签发工具使用

$ apt install golang-cfssl
$ cfssl version
Version: 1.2.0
Revision: dev
Runtime: go1.8.1

{
  "CN": "velero",
  "hosts": [],
  "key": {
    "algo": "rsa",
    "size": 2048
  },
  "names": [
    {
      "C": "CN",
      "ST": "Shanghai",
      "L": "Shanghai",
      "O": "xiexianbin.cn",
      "OU": "System"
    }
  ]
}

$ cfssl gencert -ca=/etc/kubernetes/pki/ca.crt -ca-key=/etc/kubernetes/pki/ca.key -profile=kubernetes ./velero-csr.json | cfssljson -bare velero
2022/09/01 19:07:00 [INFO] generate received request
2022/09/01 19:07:00 [INFO] received CSR
2022/09/01 19:07:00 [INFO] generating key: rsa-2048
2022/09/01 19:07:01 [INFO] encoded CSR
2022/09/01 19:07:01 [INFO] signed certificate with serial number 189907845831992997781066517490680137593355413304
2022/09/01 19:07:01 [WARNING] This certificate lacks a "hosts" field. This makes it unsuitable for
websites. For more information see the Baseline Requirements for the Issuance and Management
of Publicly-Trusted Certificates, v.1.1.6, from the CA/Browser Forum (https://cabforum.org);
specifically, section 10.2.3 ("Information Requirements").

# 签发后的证书信息
$  ls -lhart
total 20K
-rw-r--r--  1 root root  232 Sep  1 19:05 velero-csr.json
drwx------ 10 root root 4.0K Sep  1 19:05 ..
-rw-r--r--  1 root root 1.3K Sep  1 19:07 velero.pem
-rw-------  1 root root 1.7K Sep  1 19:07 velero-key.pem
-rw-r--r--  1 root root 1013 Sep  1 19:07 velero.csr