diff options
Diffstat (limited to 'crypto/src/bcpg/ArmoredOutputStream.cs')
-rw-r--r-- | crypto/src/bcpg/ArmoredOutputStream.cs | 330 |
1 files changed, 330 insertions, 0 deletions
diff --git a/crypto/src/bcpg/ArmoredOutputStream.cs b/crypto/src/bcpg/ArmoredOutputStream.cs new file mode 100644 index 000000000..b3a32c6f5 --- /dev/null +++ b/crypto/src/bcpg/ArmoredOutputStream.cs @@ -0,0 +1,330 @@ +using System; +using System.Collections; +using System.Diagnostics; +using System.IO; +using System.Reflection; +using System.Text; + +using Org.BouncyCastle.Utilities; +using Org.BouncyCastle.Utilities.IO; + +namespace Org.BouncyCastle.Bcpg +{ + /** + * Basic output stream. + */ + public class ArmoredOutputStream + : BaseOutputStream + { + private static readonly byte[] encodingTable = + { + (byte)'A', (byte)'B', (byte)'C', (byte)'D', (byte)'E', (byte)'F', (byte)'G', + (byte)'H', (byte)'I', (byte)'J', (byte)'K', (byte)'L', (byte)'M', (byte)'N', + (byte)'O', (byte)'P', (byte)'Q', (byte)'R', (byte)'S', (byte)'T', (byte)'U', + (byte)'V', (byte)'W', (byte)'X', (byte)'Y', (byte)'Z', + (byte)'a', (byte)'b', (byte)'c', (byte)'d', (byte)'e', (byte)'f', (byte)'g', + (byte)'h', (byte)'i', (byte)'j', (byte)'k', (byte)'l', (byte)'m', (byte)'n', + (byte)'o', (byte)'p', (byte)'q', (byte)'r', (byte)'s', (byte)'t', (byte)'u', + (byte)'v', + (byte)'w', (byte)'x', (byte)'y', (byte)'z', + (byte)'0', (byte)'1', (byte)'2', (byte)'3', (byte)'4', (byte)'5', (byte)'6', + (byte)'7', (byte)'8', (byte)'9', + (byte)'+', (byte)'/' + }; + + /** + * encode the input data producing a base 64 encoded byte array. + */ + private static void Encode( + Stream outStream, + int[] data, + int len) + { + Debug.Assert(len > 0); + Debug.Assert(len < 4); + + byte[] bs = new byte[4]; + int d1 = data[0]; + bs[0] = encodingTable[(d1 >> 2) & 0x3f]; + + switch (len) + { + case 1: + { + bs[1] = encodingTable[(d1 << 4) & 0x3f]; + bs[2] = (byte)'='; + bs[3] = (byte)'='; + break; + } + case 2: + { + int d2 = data[1]; + bs[1] = encodingTable[((d1 << 4) | (d2 >> 4)) & 0x3f]; + bs[2] = encodingTable[(d2 << 2) & 0x3f]; + bs[3] = (byte)'='; + break; + } + case 3: + { + int d2 = data[1]; + int d3 = data[2]; + bs[1] = encodingTable[((d1 << 4) | (d2 >> 4)) & 0x3f]; + bs[2] = encodingTable[((d2 << 2) | (d3 >> 6)) & 0x3f]; + bs[3] = encodingTable[d3 & 0x3f]; + break; + } + } + + outStream.Write(bs, 0, bs.Length); + } + + private readonly Stream outStream; + private int[] buf = new int[3]; + private int bufPtr = 0; + private Crc24 crc = new Crc24(); + private int chunkCount = 0; + private int lastb; + + private bool start = true; + private bool clearText = false; + private bool newLine = false; + + private string type; + + private static readonly string nl = Platform.NewLine; + private static readonly string headerStart = "-----BEGIN PGP "; + private static readonly string headerTail = "-----"; + private static readonly string footerStart = "-----END PGP "; + private static readonly string footerTail = "-----"; + + private static readonly string version = "BCPG C# v" + + Assembly.GetExecutingAssembly().GetName().Version; + + private readonly IDictionary headers; + + public ArmoredOutputStream(Stream outStream) + { + this.outStream = outStream; + this.headers = Platform.CreateHashtable(); + this.headers["Version"] = version; + } + + public ArmoredOutputStream(Stream outStream, IDictionary headers) + { + this.outStream = outStream; + this.headers = Platform.CreateHashtable(headers); + this.headers["Version"] = version; + } + + /** + * Set an additional header entry. + * + * @param name the name of the header entry. + * @param v the value of the header entry. + */ + public void SetHeader( + string name, + string v) + { + headers[name] = v; + } + + /** + * Reset the headers to only contain a Version string. + */ + public void ResetHeaders() + { + headers.Clear(); + headers["Version"] = version; + } + + /** + * Start a clear text signed message. + * @param hashAlgorithm + */ + public void BeginClearText( + HashAlgorithmTag hashAlgorithm) + { + string hash; + + switch (hashAlgorithm) + { + case HashAlgorithmTag.Sha1: + hash = "SHA1"; + break; + case HashAlgorithmTag.Sha256: + hash = "SHA256"; + break; + case HashAlgorithmTag.Sha384: + hash = "SHA384"; + break; + case HashAlgorithmTag.Sha512: + hash = "SHA512"; + break; + case HashAlgorithmTag.MD2: + hash = "MD2"; + break; + case HashAlgorithmTag.MD5: + hash = "MD5"; + break; + case HashAlgorithmTag.RipeMD160: + hash = "RIPEMD160"; + break; + default: + throw new IOException("unknown hash algorithm tag in beginClearText: " + hashAlgorithm); + } + + DoWrite("-----BEGIN PGP SIGNED MESSAGE-----" + nl); + DoWrite("Hash: " + hash + nl + nl); + + clearText = true; + newLine = true; + lastb = 0; + } + + public void EndClearText() + { + clearText = false; + } + + public override void WriteByte( + byte b) + { + if (clearText) + { + outStream.WriteByte(b); + + if (newLine) + { + if (!(b == '\n' && lastb == '\r')) + { + newLine = false; + } + if (b == '-') + { + outStream.WriteByte((byte)' '); + outStream.WriteByte((byte)'-'); // dash escape + } + } + if (b == '\r' || (b == '\n' && lastb != '\r')) + { + newLine = true; + } + lastb = b; + return; + } + + if (start) + { + bool newPacket = (b & 0x40) != 0; + + int tag; + if (newPacket) + { + tag = b & 0x3f; + } + else + { + tag = (b & 0x3f) >> 2; + } + + switch ((PacketTag)tag) + { + case PacketTag.PublicKey: + type = "PUBLIC KEY BLOCK"; + break; + case PacketTag.SecretKey: + type = "PRIVATE KEY BLOCK"; + break; + case PacketTag.Signature: + type = "SIGNATURE"; + break; + default: + type = "MESSAGE"; + break; + } + + DoWrite(headerStart + type + headerTail + nl); + WriteHeaderEntry("Version", (string) headers["Version"]); + + foreach (DictionaryEntry de in headers) + { + string k = (string) de.Key; + if (k != "Version") + { + string v = (string) de.Value; + WriteHeaderEntry(k, v); + } + } + + DoWrite(nl); + + start = false; + } + + if (bufPtr == 3) + { + Encode(outStream, buf, bufPtr); + bufPtr = 0; + if ((++chunkCount & 0xf) == 0) + { + DoWrite(nl); + } + } + + crc.Update(b); + buf[bufPtr++] = b & 0xff; + } + + /** + * <b>Note</b>: close does nor close the underlying stream. So it is possible to write + * multiple objects using armoring to a single stream. + */ + public override void Close() + { + if (type != null) + { + if (bufPtr > 0) + { + Encode(outStream, buf, bufPtr); + } + + DoWrite(nl + '='); + + int crcV = crc.Value; + + buf[0] = ((crcV >> 16) & 0xff); + buf[1] = ((crcV >> 8) & 0xff); + buf[2] = (crcV & 0xff); + + Encode(outStream, buf, 3); + + DoWrite(nl); + DoWrite(footerStart); + DoWrite(type); + DoWrite(footerTail); + DoWrite(nl); + + outStream.Flush(); + + type = null; + start = true; + base.Close(); + } + } + + private void WriteHeaderEntry( + string name, + string v) + { + DoWrite(name + ": " + v + nl); + } + + private void DoWrite( + string s) + { + byte[] bs = Strings.ToAsciiByteArray(s); + outStream.Write(bs, 0, bs.Length); + } + } +} |