public void TestNonIntegerTag()
{
using (MemoryStream mem = new MemoryStream(
new byte[] { 0x30, 0x03, 0x02, 0x01, 0x01 }
)) {
BERReader reader = new BERReader(mem);
BigInteger n;
Assert.False(reader.ReadInteger(out n));
}
}
public void TestIncompleteIntegerTag()
{
using (MemoryStream mem = new MemoryStream(
new byte[] { 0x02, 0x04, 0x12, 0x34, 0x56 }
)) {
BERReader reader = new BERReader(mem);
BigInteger n;
Assert.False(reader.ReadInteger(out n));
}
}
public void TestIncompleteTag()
{
using (MemoryStream mem = new MemoryStream(
new byte[] { 0x7f, 0x87, 0xef, 0xab, 0xb7, 0x6e }
)) {
BERReader reader = new BERReader(mem);
BERReader.BERTagInfo tagInfo = new BERReader.BERTagInfo();
Assert.False(reader.ReadTagInfo(ref tagInfo));
}
}
public void TestIntegerTag4()
{
using (MemoryStream mem = new MemoryStream(
new byte[] { 0x02, 0x09, 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0, 0x01 }
)) {
BERReader reader = new BERReader(mem);
BigInteger n;
Assert.True(reader.ReadInteger(out n));
Assert.AreEqual("123456789ABCDEF001", n.ToString(16));
}
}
public void TestIntegerTag3()
{
using (MemoryStream mem = new MemoryStream(
new byte[] { 0x02, 0x01, 0x00 }
)) {
BERReader reader = new BERReader(mem);
BigInteger n;
Assert.True(reader.ReadInteger(out n));
Assert.AreEqual("0", n.ToString());
}
}
public void TestLargeTag()
{
using (MemoryStream mem = new MemoryStream(
new byte[] { 0x7f, 0x87, 0xef, 0xab, 0xb7, 0x6e, 0x03, 0x02, 0x01, 0x01 }
)) {
BERReader reader = new BERReader(mem);
BERReader.BERTagInfo tagInfo = new BERReader.BERTagInfo();
Assert.True(reader.ReadTagInfo(ref tagInfo));
Assert.AreEqual(1, tagInfo.ClassBits);
Assert.AreEqual(true, tagInfo.IsConstructed);
Assert.AreEqual(0x7deadbee, tagInfo.TagNumber);
Assert.AreEqual(3, tagInfo.Length);
}
}
/// <summary>
/// Read OpenSSH SSH2 private key parameters.
/// </summary>
/// <param name="passphrase">passphrase for decrypt the key file</param>
/// <param name="keyPair">key pair</param>
/// <param name="comment">comment or empty if it didn't exist</param>
public void Load(string passphrase, out KeyPair keyPair, out string comment) {
if (keyFile == null)
throw new SSHException("A key file is not loaded yet");
KeyType keyType;
String base64Text;
bool encrypted = false;
CipherAlgorithm? encryption = null;
byte[] iv = null;
int keySize = 0;
int ivSize = 0;
using (StreamReader sreader = GetStreamReader()) {
string line = sreader.ReadLine();
if (line == null)
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (unexpected eof)");
if (line == PrivateKeyFileHeader.SSH2_OPENSSH_HEADER_RSA)
keyType = KeyType.RSA;
else if (line == PrivateKeyFileHeader.SSH2_OPENSSH_HEADER_DSA)
keyType = KeyType.DSA;
else
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (unexpected key type)");
string footer = line.Replace("BEGIN", "END");
StringBuilder buf = new StringBuilder();
comment = String.Empty;
while (true) {
line = sreader.ReadLine();
if (line == null)
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (unexpected eof)");
if (line == footer)
break;
if (line.IndexOf(':') >= 0) {
if (line.StartsWith("Proc-Type:")) {
string[] w = line.Substring("Proc-Type:".Length).Trim().Split(',');
if (w.Length < 1)
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (invalid Proc-Type)");
if (w[0] != "4")
throw new SSHException(Strings.GetString("UnsupportedPrivateKeyFormat")
+ " (" + Strings.GetString("Reason_UnsupportedProcType") + ")");
if (w.Length >= 2 && w[1] == "ENCRYPTED")
encrypted = true;
}
else if (line.StartsWith("DEK-Info:")) {
string[] w = line.Substring("DEK-Info:".Length).Trim().Split(',');
if (w.Length < 2)
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (invalid DEK-Info)");
switch(w[0]) {
case "DES-EDE3-CBC":
encryption = CipherAlgorithm.TripleDES;
ivSize = 8;
keySize = 24;
break;
case "AES-128-CBC":
encryption = CipherAlgorithm.AES128;
ivSize = 16;
keySize = 16;
break;
default:
throw new SSHException(Strings.GetString("UnsupportedPrivateKeyFormat")
+ " (" + Strings.GetString("Reason_UnsupportedEncryptionType") + ")");
}
iv = HexToByteArray(w[1]);
if (iv == null || iv.Length != ivSize)
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (invalid IV)");
}
}
else
buf.Append(line);
}
base64Text = buf.ToString();
}
byte[] keydata = Base64.Decode(Encoding.ASCII.GetBytes(base64Text));
if (encrypted) {
if (!encryption.HasValue || iv == null)
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (missing encryption type or IV)");
byte[] key = OpenSSHPassphraseToKey(passphrase, iv, keySize);
Cipher cipher = CipherFactory.CreateCipher(SSHProtocol.SSH2, encryption.Value, key, iv);
if (keydata.Length % cipher.BlockSize != 0)
throw new SSHException(Strings.GetString("NotValidPrivateKeyFile") + " (invalid key data size)");
cipher.Decrypt(keydata, 0, keydata.Length, keydata, 0);
}
using (MemoryStream keyDataStream = new MemoryStream(keydata, false)) {
BERReader reader = new BERReader(keyDataStream);
if (!reader.ReadSequence())
throw new SSHException(Strings.GetString("WrongPassphrase"));
if (keyType == KeyType.RSA) {
/* from OpenSSL rsa_asn1.c
*
* ASN1_SIMPLE(RSA, version, LONG),
* ASN1_SIMPLE(RSA, n, BIGNUM),
* ASN1_SIMPLE(RSA, e, BIGNUM),
* ASN1_SIMPLE(RSA, d, BIGNUM),
* ASN1_SIMPLE(RSA, p, BIGNUM),
* ASN1_SIMPLE(RSA, q, BIGNUM),
* ASN1_SIMPLE(RSA, dmp1, BIGNUM),
* ASN1_SIMPLE(RSA, dmq1, BIGNUM),
* ASN1_SIMPLE(RSA, iqmp, BIGNUM)
*/
BigInteger v, n, e, d, p, q, dmp1, dmq1, iqmp;
if (!reader.ReadInteger(out v) ||
!reader.ReadInteger(out n) ||
!reader.ReadInteger(out e) ||
!reader.ReadInteger(out d) ||
!reader.ReadInteger(out p) ||
!reader.ReadInteger(out q) ||
!reader.ReadInteger(out dmp1) ||
!reader.ReadInteger(out dmq1) ||
!reader.ReadInteger(out iqmp)) {
throw new SSHException(Strings.GetString("WrongPassphrase"));
}
BigInteger u = p.modInverse(q); // inverse of p mod q
keyPair = new RSAKeyPair(e, d, n, u, p, q);
}
else if (keyType == KeyType.DSA) {
/* from OpenSSL dsa_asn1.c
*
* ASN1_SIMPLE(DSA, version, LONG),
* ASN1_SIMPLE(DSA, p, BIGNUM),
* ASN1_SIMPLE(DSA, q, BIGNUM),
* ASN1_SIMPLE(DSA, g, BIGNUM),
* ASN1_SIMPLE(DSA, pub_key, BIGNUM),
* ASN1_SIMPLE(DSA, priv_key, BIGNUM)
*/
BigInteger v, p, q, g, y, x;
if (!reader.ReadInteger(out v) ||
!reader.ReadInteger(out p) ||
!reader.ReadInteger(out q) ||
!reader.ReadInteger(out g) ||
!reader.ReadInteger(out y) ||
!reader.ReadInteger(out x)) {
throw new SSHException(Strings.GetString("WrongPassphrase"));
}
keyPair = new DSAKeyPair(p, g, q, y, x);
}
else {
throw new SSHException("Unknown file type. This should not happen.");
}
}
}
