1 /* 2 Copyright 2018 The Kubernetes Authors. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 */ 16 17 package generator 18 19 import ( 20 "crypto/tls" 21 "crypto/x509" 22 "encoding/pem" 23 "time" 24 ) 25 26 // ValidCACert think cert and key are valid if they meet the following requirements: 27 // - key and cert are valid pair 28 // - caCert is the root ca of cert 29 // - cert is for dnsName 30 // - cert won't expire before time 31 func ValidCACert(key, cert, caCert []byte, dnsName string, time time.Time) bool { 32 if len(key) == 0 || len(cert) == 0 || len(caCert) == 0 { 33 return false 34 } 35 // Verify key and cert are valid pair 36 _, err := tls.X509KeyPair(cert, key) 37 if err != nil { 38 return false 39 } 40 41 // Verify cert is valid for at least 1 year. 42 pool := x509.NewCertPool() 43 if !pool.AppendCertsFromPEM(caCert) { 44 return false 45 } 46 block, _ := pem.Decode([]byte(cert)) 47 if block == nil { 48 return false 49 } 50 c, err := x509.ParseCertificate(block.Bytes) 51 if err != nil { 52 return false 53 } 54 ops := x509.VerifyOptions{ 55 DNSName: dnsName, 56 Roots: pool, 57 CurrentTime: time, 58 } 59 _, err = c.Verify(ops) 60 return err == nil 61 } 62