使用BouncyCastle c#进行PgP加密和解密

时间:2011-08-08 19:49:18

标签: c# encryption bouncycastle pgp

我看过很多帖子,其中有一些教程,但似乎都没有。有时,他们会引用一些未找到的类。我是否可以指向一个可以获得简单教程的地方,该教程展示了如何加密和解密文件。

我对Pgp很新,欢迎任何帮助。

3 个答案:

答案 0 :(得分:23)

我知道这个问题已经存在多年了,但是对于使用Bouncy Castle的PGP解密相关搜索,Google仍然是#1或#2。由于似乎很难找到一个完整,简洁的例子,我想在这里分享我的工作解决方案来解密PGP文件。这只是其源文件中包含的Bouncy Castle示例的修改版本。

using System;
using System.IO;
using Org.BouncyCastle.Bcpg.OpenPgp;
using Org.BouncyCastle.Utilities.IO;

namespace PGPDecrypt
{
    class Program
    {
        static void Main(string[] args)
        {
            DecryptFile(
                @"path_to_encrypted_file.pgp",
                @"path_to_secret_key.asc",
                "your_password_here".ToCharArray(), 
                "output.txt"
            );
        }

        private static void DecryptFile(
            string inputFileName,
            string keyFileName,
            char[] passwd,
            string defaultFileName)
        {
            using (Stream input = File.OpenRead(inputFileName),
                   keyIn = File.OpenRead(keyFileName))
            {
                DecryptFile(input, keyIn, passwd, defaultFileName);
            }
        }

        private static void DecryptFile(
            Stream inputStream,
            Stream keyIn,
            char[] passwd,
            string defaultFileName)
        {
            inputStream = PgpUtilities.GetDecoderStream(inputStream);

            try
            {
                PgpObjectFactory pgpF = new PgpObjectFactory(inputStream);
                PgpEncryptedDataList enc;

                PgpObject o = pgpF.NextPgpObject();
                //
                // the first object might be a PGP marker packet.
                //
                if (o is PgpEncryptedDataList)
                {
                    enc = (PgpEncryptedDataList)o;
                }
                else
                {
                    enc = (PgpEncryptedDataList)pgpF.NextPgpObject();
                }

                //
                // find the secret key
                //
                PgpPrivateKey sKey = null;
                PgpPublicKeyEncryptedData pbe = null;
                PgpSecretKeyRingBundle pgpSec = new PgpSecretKeyRingBundle(
                    PgpUtilities.GetDecoderStream(keyIn));

                foreach (PgpPublicKeyEncryptedData pked in enc.GetEncryptedDataObjects())
                {
                    sKey = FindSecretKey(pgpSec, pked.KeyId, passwd);

                    if (sKey != null)
                    {
                        pbe = pked;
                        break;
                    }
                }

                if (sKey == null)
                {
                    throw new ArgumentException("secret key for message not found.");
                }

                Stream clear = pbe.GetDataStream(sKey);

                PgpObjectFactory plainFact = new PgpObjectFactory(clear);

                PgpObject message = plainFact.NextPgpObject();

                if (message is PgpCompressedData)
                {
                    PgpCompressedData cData = (PgpCompressedData)message;
                    PgpObjectFactory pgpFact = new PgpObjectFactory(cData.GetDataStream());

                    message = pgpFact.NextPgpObject();
                }

                if (message is PgpLiteralData)
                {
                    PgpLiteralData ld = (PgpLiteralData)message;

                    string outFileName = ld.FileName;
                    if (outFileName.Length == 0)
                    {
                        outFileName = defaultFileName;
                    }

                    Stream fOut = File.Create(outFileName);
                    Stream unc = ld.GetInputStream();
                    Streams.PipeAll(unc, fOut);
                    fOut.Close();
                }
                else if (message is PgpOnePassSignatureList)
                {
                    throw new PgpException("encrypted message contains a signed message - not literal data.");
                }
                else
                {
                    throw new PgpException("message is not a simple encrypted file - type unknown.");
                }

                if (pbe.IsIntegrityProtected())
                {
                    if (!pbe.Verify())
                    {
                        Console.Error.WriteLine("message failed integrity check");
                    }
                    else
                    {
                        Console.Error.WriteLine("message integrity check passed");
                    }
                }
                else
                {
                    Console.Error.WriteLine("no message integrity check");
                }
            }
            catch (PgpException e)
            {
                Console.Error.WriteLine(e);

                Exception underlyingException = e.InnerException;
                if (underlyingException != null)
                {
                    Console.Error.WriteLine(underlyingException.Message);
                    Console.Error.WriteLine(underlyingException.StackTrace);
                }
            }
        }

        private static PgpPrivateKey FindSecretKey(PgpSecretKeyRingBundle pgpSec, long keyID, char[] pass)
        {
            PgpSecretKey pgpSecKey = pgpSec.GetSecretKey(keyID);

            if (pgpSecKey == null)
            {
                return null;
            }

            return pgpSecKey.ExtractPrivateKey(pass);
        }
    }
}

答案 1 :(得分:3)

这是怎么回事:

PartialInputStream during Bouncycastle PGP decryption

此外,zip包含以下示例:

http://www.bouncycastle.org/csharp/

希望这会有所帮助。如果你仍然陷入困境,请发布一些关于编译器抱怨的类的更多细节,社区将会看一下。

答案 2 :(得分:1)

我使用了 PgpCore 包,它是 Portable.BouncyCastle 的包装器。

它非常干净且易于使用。多个示例可用 here