// NewDecryptTest generates an RSA decryption test.
func NewDecryptTest(decrypter crypto.Decrypter) testapi.TestFunc {
ptxt := []byte("Test Plaintext")
r := rand.Reader
return func() (err error) {
var c, m []byte
if c, err = rsa.EncryptPKCS1v15(r, decrypter.Public().(*rsa.PublicKey), ptxt); err != nil {
return
}
if m, err = decrypter.Decrypt(r, c, &rsa.PKCS1v15DecryptOptions{}); err != nil {
return
}
if bytes.Compare(ptxt, m) != 0 {
return errors.New("rsa decrypt failed")
}
if m, err = decrypter.Decrypt(r, c, &rsa.PKCS1v15DecryptOptions{SessionKeyLen: len(ptxt)}); err != nil {
return
}
if bytes.Compare(ptxt, m) != 0 {
return errors.New("rsa decrypt failed")
}
if m, err = decrypter.Decrypt(r, c, &rsa.PKCS1v15DecryptOptions{SessionKeyLen: len(ptxt) + 1}); err != nil {
return
}
if bytes.Compare(ptxt, m) == 0 {
return errors.New("rsa decrypt suceeded despite incorrect SessionKeyLen")
}
return nil
}
}
// testKey performs and verifies all possible opaque private key operations.
func testKey(priv crypto.Signer) (err error) {
ptxt := []byte("Test Plaintext")
r := rand.Reader
hashes := []crypto.Hash{
crypto.MD5SHA1,
crypto.SHA1,
crypto.SHA224,
crypto.SHA256,
crypto.SHA384,
crypto.SHA512,
}
for _, h := range hashes {
var msg, sig []byte
if h == crypto.MD5SHA1 {
msg = append(hashPtxt(crypto.MD5, ptxt), hashPtxt(crypto.SHA1, ptxt)...)
} else {
msg = hashPtxt(h, ptxt)
}
if sig, err = priv.Sign(r, msg, h); err != nil {
return
}
switch pub := priv.Public().(type) {
case *rsa.PublicKey:
if err = rsa.VerifyPKCS1v15(pub, h, msg, sig); err != nil {
return
}
case *ecdsa.PublicKey:
ecdsaSig := new(struct{ R, S *big.Int })
asn1.Unmarshal(sig, ecdsaSig)
if !ecdsa.Verify(pub, msg, ecdsaSig.R, ecdsaSig.S) {
return errors.New("ecdsa verify failed")
}
default:
return errors.New("unknown public key type")
}
}
if pub, ok := priv.Public().(*rsa.PublicKey); ok {
var c, m []byte
if c, err = rsa.EncryptPKCS1v15(r, pub, ptxt); err != nil {
return
}
var decrypter crypto.Decrypter
if decrypter, ok = priv.(crypto.Decrypter); !ok {
return errors.New("rsa public key but cannot decrypt")
}
if m, err = decrypter.Decrypt(r, c, &rsa.PKCS1v15DecryptOptions{}); err != nil {
return
}
if bytes.Compare(ptxt, m) != 0 {
return errors.New("rsa decrypt failed")
}
if m, err = decrypter.Decrypt(r, c, &rsa.PKCS1v15DecryptOptions{SessionKeyLen: len(ptxt)}); err != nil {
return
}
if bytes.Compare(ptxt, m) != 0 {
return errors.New("rsa decrypt failed")
}
if m, err = decrypter.Decrypt(r, c, &rsa.PKCS1v15DecryptOptions{SessionKeyLen: len(ptxt) + 1}); err != nil {
return
}
if bytes.Compare(ptxt, m) == 0 {
return errors.New("rsa decrypt suceeded despite incorrect SessionKeyLen")
}
}
return nil
}