using Renci.SshNet.Abstractions; using Renci.SshNet.Common; using Renci.SshNet.Security; using Renci.SshNet.Security.Cryptography.Ciphers; using Renci.SshNet.Security.Cryptography.Ciphers.Modes; using Renci.SshNet.Security.Cryptography.Ciphers.Paddings; using SshNet.Security.Cryptography; using System; using System.Collections.Generic; using System.Globalization; using System.IO; using System.Security.Cryptography; using System.Text; using System.Text.RegularExpressions; namespace Renci.SshNet { public class PrivateKeyFile : IDisposable { private class SshDataReader : SshData { public SshDataReader(byte[] data) { Load(data); } public new uint ReadUInt32() { return base.ReadUInt32(); } public new string ReadString(Encoding encoding) { return base.ReadString(encoding); } public new byte[] ReadBytes(int length) { return base.ReadBytes(length); } public BigInteger ReadBigIntWithBits() { int num = (int)base.ReadUInt32(); num = (num + 7) / 8; byte[] array = base.ReadBytes(num); byte[] array2 = new byte[array.Length + 1]; Buffer.BlockCopy(array, 0, array2, 1, array.Length); return new BigInteger(array2.Reverse()); } protected override void LoadData() { } protected override void SaveData() { } } private static readonly Regex PrivateKeyRegex = new Regex("^-+ *BEGIN (?<keyName>\\w+( \\w+)*) PRIVATE KEY *-+\\r?\\n((Proc-Type: 4,ENCRYPTED\\r?\\nDEK-Info: (?<cipherName>[A-Z0-9-]+),(?<salt>[A-F0-9]+)\\r?\\n\\r?\\n)|(Comment: \"?[^\\r\\n]*\"?\\r?\\n))?(?<data>([a-zA-Z0-9/+=]{1,80}\\r?\\n)+)-+ *END \\k<keyName> PRIVATE KEY *-+", RegexOptions.Multiline); private Key _key; private bool _isDisposed; public HostAlgorithm HostKey { get; set; } public PrivateKeyFile(Stream privateKey) { Open(privateKey, null); } public PrivateKeyFile(string fileName) : this(fileName, null) { } public PrivateKeyFile(string fileName, string passPhrase) { if (string.IsNullOrEmpty(fileName)) throw new ArgumentNullException("fileName"); using (FileStream privateKey = File.Open(fileName, FileMode.Open, FileAccess.Read, FileShare.Read)) Open(privateKey, passPhrase); } public PrivateKeyFile(Stream privateKey, string passPhrase) { Open(privateKey, passPhrase); } private void Open(Stream privateKey, string passPhrase) { if (privateKey == null) throw new ArgumentNullException("privateKey"); Match match = default(Match); using (StreamReader streamReader = new StreamReader(privateKey)) { string input = streamReader.ReadToEnd(); match = PrivateKeyRegex.Match(input); } if (!match.Success) throw new SshException("Invalid private key file."); string text = match.Result("${keyName}"); string text2 = match.Result("${cipherName}"); string text3 = match.Result("${salt}"); byte[] array = Convert.FromBase64String(match.Result("${data}")); byte[] data; if (!string.IsNullOrEmpty(text2) && !string.IsNullOrEmpty(text3)) { if (string.IsNullOrEmpty(passPhrase)) throw new SshPassPhraseNullOrEmptyException("Private key is encrypted but passphrase is empty."); byte[] array2 = new byte[text3.Length / 2]; for (int i = 0; i < array2.Length; i++) { array2[i] = Convert.ToByte(text3.Substring(i * 2, 2), 16); } CipherInfo cipherInfo; if (!(text2 == "DES-EDE3-CBC")) { if (!(text2 == "DES-EDE3-CFB")) { if (!(text2 == "DES-CBC")) { if (!(text2 == "AES-128-CBC")) { if (!(text2 == "AES-192-CBC")) { if (!(text2 == "AES-256-CBC")) throw new SshException(string.Format(CultureInfo.CurrentCulture, "Private key cipher \"{0}\" is not supported.", new object[1] { text2 })); cipherInfo = new CipherInfo(256, (byte[] key, byte[] iv) => new AesCipher(key, new CbcCipherMode(iv), new PKCS7Padding())); } else cipherInfo = new CipherInfo(192, (byte[] key, byte[] iv) => new AesCipher(key, new CbcCipherMode(iv), new PKCS7Padding())); } else cipherInfo = new CipherInfo(128, (byte[] key, byte[] iv) => new AesCipher(key, new CbcCipherMode(iv), new PKCS7Padding())); } else cipherInfo = new CipherInfo(64, (byte[] key, byte[] iv) => new DesCipher(key, new CbcCipherMode(iv), new PKCS7Padding())); } else cipherInfo = new CipherInfo(192, (byte[] key, byte[] iv) => new TripleDesCipher(key, new CfbCipherMode(iv), new PKCS7Padding())); } else cipherInfo = new CipherInfo(192, (byte[] key, byte[] iv) => new TripleDesCipher(key, new CbcCipherMode(iv), new PKCS7Padding())); data = DecryptKey(cipherInfo, array, passPhrase, array2); } else data = array; if (!(text == "RSA")) { if (!(text == "DSA")) { if (!(text == "SSH2 ENCRYPTED")) throw new NotSupportedException(string.Format(CultureInfo.CurrentCulture, "Key '{0}' is not supported.", new object[1] { text })); SshDataReader sshDataReader = new SshDataReader(data); if (sshDataReader.ReadUInt32() != 1064303083) throw new SshException("Invalid SSH2 private key."); sshDataReader.ReadUInt32(); string text4 = sshDataReader.ReadString(SshData.Ascii); string a = sshDataReader.ReadString(SshData.Ascii); int num = (int)sshDataReader.ReadUInt32(); byte[] data2; if (a == "none") data2 = sshDataReader.ReadBytes(num); else { if (!(a == "3des-cbc")) throw new SshException($"""{text2}"""); if (string.IsNullOrEmpty(passPhrase)) throw new SshPassPhraseNullOrEmptyException("Private key is encrypted but passphrase is empty."); data2 = new TripleDesCipher(GetCipherKey(passPhrase, 24), new CbcCipherMode(new byte[8]), new PKCS7Padding()).Decrypt(sshDataReader.ReadBytes(num)); } sshDataReader = new SshDataReader(data2); if (sshDataReader.ReadUInt32() > num - 4) throw new SshException("Invalid passphrase."); if (text4 == "if-modn{sign{rsa-pkcs1-sha1},encrypt{rsa-pkcs1v2-oaep}}") { BigInteger exponent = sshDataReader.ReadBigIntWithBits(); BigInteger d = sshDataReader.ReadBigIntWithBits(); BigInteger modulus = sshDataReader.ReadBigIntWithBits(); BigInteger inverseQ = sshDataReader.ReadBigIntWithBits(); BigInteger q = sshDataReader.ReadBigIntWithBits(); BigInteger p = sshDataReader.ReadBigIntWithBits(); _key = new RsaKey(modulus, exponent, d, p, q, inverseQ); HostKey = new KeyHostAlgorithm("ssh-rsa", _key); } else { if (!(text4 == "dl-modp{sign{dsa-nist-sha1},dh{plain}}")) throw new NotSupportedException($"""{text4}"""); if (sshDataReader.ReadUInt32() != 0) throw new SshException("Invalid private key"); BigInteger p2 = sshDataReader.ReadBigIntWithBits(); BigInteger g = sshDataReader.ReadBigIntWithBits(); BigInteger q2 = sshDataReader.ReadBigIntWithBits(); BigInteger y = sshDataReader.ReadBigIntWithBits(); BigInteger x = sshDataReader.ReadBigIntWithBits(); _key = new DsaKey(p2, q2, g, y, x); HostKey = new KeyHostAlgorithm("ssh-dss", _key); } } else { _key = new DsaKey(data); HostKey = new KeyHostAlgorithm("ssh-dss", _key); } } else { _key = new RsaKey(data); HostKey = new KeyHostAlgorithm("ssh-rsa", _key); } } private static byte[] GetCipherKey(string passphrase, int length) { List<byte> list = new List<byte>(); MD5 val = CryptoAbstraction.CreateMD5(); try { byte[] bytes = Encoding.UTF8.GetBytes(passphrase); byte[] array = ((HashAlgorithm)val).ComputeHash(bytes); list.AddRange(array); while (list.Count < length) { array = bytes.Concat(array); array = ((HashAlgorithm)val).ComputeHash(array); list.AddRange(array); } } finally { ((IDisposable)val)?.Dispose(); } return list.ToArray().Take(length); } private static byte[] DecryptKey(CipherInfo cipherInfo, byte[] cipherData, string passPhrase, byte[] binarySalt) { if (cipherInfo == null) throw new ArgumentNullException("cipherInfo"); if (cipherData == null) throw new ArgumentNullException("cipherData"); if (binarySalt == null) throw new ArgumentNullException("binarySalt"); List<byte> list = new List<byte>(); MD5 val = CryptoAbstraction.CreateMD5(); try { byte[] array = Encoding.UTF8.GetBytes(passPhrase).Concat(binarySalt.Take(8)); byte[] array2 = ((HashAlgorithm)val).ComputeHash(array); list.AddRange(array2); while (list.Count < cipherInfo.KeySize / 8) { array2 = array2.Concat(array); array2 = ((HashAlgorithm)val).ComputeHash(array2); list.AddRange(array2); } } finally { ((IDisposable)val)?.Dispose(); } return cipherInfo.Cipher(list.ToArray(), binarySalt).Decrypt(cipherData); } public void Dispose() { Dispose(true); GC.SuppressFinalize(this); } protected virtual void Dispose(bool disposing) { if (!_isDisposed && disposing) { Key key = _key; if (key != null) { ((IDisposable)key).Dispose(); _key = null; } _isDisposed = true; } } ~PrivateKeyFile() { Dispose(false); } } }