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|
package main
import (
"crypto/tls"
"crypto/x509"
"fmt"
"os"
"encoding/pem"
)
func getcert(server string) (*x509.Certificate, error){
conn, err := tls.Dial("tcp", fmt.Sprintf("%s:443", server), &tls.Config{ServerName: server})
if err != nil {
return nil, err
}
defer conn.Close()
chain := conn.ConnectionState().PeerCertificates
return chain[len(chain)-2], nil
}
func main() {
for _, server := range os.Args[1:] {
cert, err := getcert(server)
if err != nil {
fmt.Fprintf(os.Stderr, "Could not get certificate from server %q: %q\n", server, err)
os.Exit(1)
}
block := pem.Block{
Type: "CERTIFICATE",
Headers: nil,
Bytes: cert.Raw,
}
pem.Encode(os.Stdout, &block)
}
}
|
