boulder/test/certs.go

107 lines
3.6 KiB
Go

package test
import (
"crypto"
"crypto/ecdsa"
"crypto/rand"
"crypto/rsa"
"crypto/x509"
"encoding/hex"
"encoding/pem"
"errors"
"fmt"
"io/ioutil"
"math/big"
"testing"
)
// LoadSigner loads a PEM private key specified by filename or returns an error.
// Can be paired with issuance.LoadCertificate to get both a CA cert and its
// associated private key for use in signing throwaway test certs.
func LoadSigner(filename string) (crypto.Signer, error) {
keyBytes, err := ioutil.ReadFile(filename)
if err != nil {
return nil, err
}
// pem.Decode does not return an error as its 2nd arg, but instead the "rest"
// that was leftover from parsing the PEM block. We only care if the decoded
// PEM block was empty for this test function.
block, _ := pem.Decode(keyBytes)
if block == nil {
return nil, errors.New("Unable to decode private key PEM bytes")
}
// Try decoding as an RSA private key
if rsaKey, err := x509.ParsePKCS1PrivateKey(block.Bytes); err == nil {
return rsaKey, nil
}
// Try decoding as a PKCS8 private key
if key, err := x509.ParsePKCS8PrivateKey(block.Bytes); err == nil {
// Determine the key's true type and return it as a crypto.Signer
switch k := key.(type) {
case *rsa.PrivateKey:
return k, nil
case *ecdsa.PrivateKey:
return k, nil
}
}
// Try as an ECDSA private key
if ecdsaKey, err := x509.ParseECPrivateKey(block.Bytes); err == nil {
return ecdsaKey, nil
}
// Nothing worked! Fail hard.
return nil, errors.New("Unable to decode private key PEM bytes")
}
// ThrowAwayCert is a small test helper function that creates a self-signed
// certificate for nameCount random example.com subdomains and returns the
// parsed certificate and the random serial in string form or aborts the test.
// The certificate returned from this function is the bare minimum needed for
// most tests and isn't a robust example of a complete end entity certificate.
func ThrowAwayCert(t *testing.T, nameCount int) (string, *x509.Certificate) {
var serialBytes [16]byte
_, _ = rand.Read(serialBytes[:])
sn := big.NewInt(0).SetBytes(serialBytes[:])
return ThrowAwayCertWithSerial(t, nameCount, sn, nil)
}
// ThrowAwayCertWithSerial is a small test helper function that creates a
// certificate for nameCount random example.com subdomains and returns the
// parsed certificate and the serial in string form or aborts the test.
// The new throwaway certificate is always self-signed (with a random key),
// but will appear to be issued from issuer if provided.
// The certificate returned from this function is the bare minimum needed for
// most tests and isn't a robust example of a complete end entity certificate.
func ThrowAwayCertWithSerial(t *testing.T, nameCount int, sn *big.Int, issuer *x509.Certificate) (string, *x509.Certificate) {
k, err := rsa.GenerateKey(rand.Reader, 512)
AssertNotError(t, err, "rsa.GenerateKey failed")
var names []string
for i := 0; i < nameCount; i++ {
var nameBytes [3]byte
_, _ = rand.Read(nameBytes[:])
names = append(names, fmt.Sprintf("%s.example.com", hex.EncodeToString(nameBytes[:])))
}
template := &x509.Certificate{
SerialNumber: sn,
DNSNames: names,
IssuingCertificateURL: []string{"http://localhost:4001/acme/issuer-cert/1234"},
}
if issuer == nil {
issuer = template
}
testCertDER, err := x509.CreateCertificate(rand.Reader, template, issuer, &k.PublicKey, k)
AssertNotError(t, err, "x509.CreateCertificate failed")
testCert, err := x509.ParseCertificate(testCertDER)
AssertNotError(t, err, "failed to parse self-signed cert DER")
return fmt.Sprintf("%036x", sn), testCert
}