go-ricochet/utils/tor.go

20 lines
514 B
Go

package utils
import (
"crypto/sha1"
"encoding/base32"
"strings"
)
// GetTorHostname takes a []byte contained a DER-encoded RSA public key
// and returns the first 16 bytes of the base32 encoded sha1 hash of the key.
// This is the onion hostname of the tor service represented by the public key.
func GetTorHostname(publicKeyBytes []byte) string {
h := sha1.New()
h.Write(publicKeyBytes)
sha1bytes := h.Sum(nil)
data := base32.StdEncoding.EncodeToString(sha1bytes)
return strings.ToLower(data[0:16])
}