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Forked from laher/loadchain.go
Created February 14, 2017 12:21
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how to load a certificate chain in Go. See how https://github.com succeeds and https://facebook.com fails.
package main
import (
"fmt"
"net/http"
"crypto/tls"
"crypto/x509"
"encoding/pem"
)
var chain=`-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`
func decodePem(certInput string) tls.Certificate {
var cert tls.Certificate
certPEMBlock := []byte(certInput)
var certDERBlock *pem.Block
for {
certDERBlock, certPEMBlock = pem.Decode(certPEMBlock)
if certDERBlock == nil {
break
}
if certDERBlock.Type == "CERTIFICATE" {
cert.Certificate = append(cert.Certificate, certDERBlock.Bytes)
}
}
return cert
}
func main() {
certChain := decodePem(chain)
conf := tls.Config { }
conf.RootCAs = x509.NewCertPool()
for _, cert := range certChain.Certificate {
x509Cert, err := x509.ParseCertificate(cert)
if err != nil {
panic(err)
}
conf.RootCAs.AddCert(x509Cert)
}
conf.BuildNameToCertificate()
tr := http.Transport{ TLSClientConfig: &conf }
client := &http.Client{Transport: &tr}
_, err := client.Get("https://github.com/")
if err != nil {
fmt.Println(err)
}
_, err = client.Get("https://facebook.com/")
if err != nil {
fmt.Println(err)
}
}
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