diff options
Diffstat (limited to 'crypto/src/bcpg/SignaturePacket.cs')
| -rw-r--r-- | crypto/src/bcpg/SignaturePacket.cs | 472 |
1 files changed, 472 insertions, 0 deletions
diff --git a/crypto/src/bcpg/SignaturePacket.cs b/crypto/src/bcpg/SignaturePacket.cs new file mode 100644 index 000000000..605ce84c4 --- /dev/null +++ b/crypto/src/bcpg/SignaturePacket.cs @@ -0,0 +1,472 @@ +using System; +using System.Collections; +using System.IO; + +using Org.BouncyCastle.Bcpg.Sig; +using Org.BouncyCastle.Utilities; +using Org.BouncyCastle.Utilities.Date; + +namespace Org.BouncyCastle.Bcpg +{ + /// <remarks>Generic signature packet.</remarks> + public class SignaturePacket + : ContainedPacket //, PublicKeyAlgorithmTag + { + private int version; + private int signatureType; + private long creationTime; + private long keyId; + private PublicKeyAlgorithmTag keyAlgorithm; + private HashAlgorithmTag hashAlgorithm; + private MPInteger[] signature; + private byte[] fingerprint; + private SignatureSubpacket[] hashedData; + private SignatureSubpacket[] unhashedData; + private byte[] signatureEncoding; + + internal SignaturePacket( + BcpgInputStream bcpgIn) + { + version = bcpgIn.ReadByte(); + + if (version == 3 || version == 2) + { +// int l = + bcpgIn.ReadByte(); + + signatureType = bcpgIn.ReadByte(); + creationTime = (((long)bcpgIn.ReadByte() << 24) | ((long)bcpgIn.ReadByte() << 16) + | ((long)bcpgIn.ReadByte() << 8) | (uint)bcpgIn.ReadByte()) * 1000L; + + keyId |= (long)bcpgIn.ReadByte() << 56; + keyId |= (long)bcpgIn.ReadByte() << 48; + keyId |= (long)bcpgIn.ReadByte() << 40; + keyId |= (long)bcpgIn.ReadByte() << 32; + keyId |= (long)bcpgIn.ReadByte() << 24; + keyId |= (long)bcpgIn.ReadByte() << 16; + keyId |= (long)bcpgIn.ReadByte() << 8; + keyId |= (uint)bcpgIn.ReadByte(); + + keyAlgorithm = (PublicKeyAlgorithmTag) bcpgIn.ReadByte(); + hashAlgorithm = (HashAlgorithmTag) bcpgIn.ReadByte(); + } + else if (version == 4) + { + signatureType = bcpgIn.ReadByte(); + keyAlgorithm = (PublicKeyAlgorithmTag) bcpgIn.ReadByte(); + hashAlgorithm = (HashAlgorithmTag) bcpgIn.ReadByte(); + + int hashedLength = (bcpgIn.ReadByte() << 8) | bcpgIn.ReadByte(); + byte[] hashed = new byte[hashedLength]; + + bcpgIn.ReadFully(hashed); + + // + // read the signature sub packet data. + // + SignatureSubpacketsParser sIn = new SignatureSubpacketsParser( + new MemoryStream(hashed, false)); + + IList v = Platform.CreateArrayList(); + SignatureSubpacket sub; + while ((sub = sIn.ReadPacket()) != null) + { + v.Add(sub); + } + + hashedData = new SignatureSubpacket[v.Count]; + + for (int i = 0; i != hashedData.Length; i++) + { + SignatureSubpacket p = (SignatureSubpacket)v[i]; + if (p is IssuerKeyId) + { + keyId = ((IssuerKeyId)p).KeyId; + } + else if (p is SignatureCreationTime) + { + creationTime = DateTimeUtilities.DateTimeToUnixMs( + ((SignatureCreationTime)p).GetTime()); + } + + hashedData[i] = p; + } + + int unhashedLength = (bcpgIn.ReadByte() << 8) | bcpgIn.ReadByte(); + byte[] unhashed = new byte[unhashedLength]; + + bcpgIn.ReadFully(unhashed); + + sIn = new SignatureSubpacketsParser(new MemoryStream(unhashed, false)); + + v.Clear(); + + while ((sub = sIn.ReadPacket()) != null) + { + v.Add(sub); + } + + unhashedData = new SignatureSubpacket[v.Count]; + + for (int i = 0; i != unhashedData.Length; i++) + { + SignatureSubpacket p = (SignatureSubpacket)v[i]; + if (p is IssuerKeyId) + { + keyId = ((IssuerKeyId)p).KeyId; + } + + unhashedData[i] = p; + } + } + else + { + throw new Exception("unsupported version: " + version); + } + + fingerprint = new byte[2]; + bcpgIn.ReadFully(fingerprint); + + switch (keyAlgorithm) + { + case PublicKeyAlgorithmTag.RsaGeneral: + case PublicKeyAlgorithmTag.RsaSign: + MPInteger v = new MPInteger(bcpgIn); + signature = new MPInteger[]{ v }; + break; + case PublicKeyAlgorithmTag.Dsa: + MPInteger r = new MPInteger(bcpgIn); + MPInteger s = new MPInteger(bcpgIn); + signature = new MPInteger[]{ r, s }; + break; + case PublicKeyAlgorithmTag.ElGamalEncrypt: // yep, this really does happen sometimes. + case PublicKeyAlgorithmTag.ElGamalGeneral: + MPInteger p = new MPInteger(bcpgIn); + MPInteger g = new MPInteger(bcpgIn); + MPInteger y = new MPInteger(bcpgIn); + signature = new MPInteger[]{ p, g, y }; + break; + default: + if (keyAlgorithm >= PublicKeyAlgorithmTag.Experimental_1 && keyAlgorithm <= PublicKeyAlgorithmTag.Experimental_11) + { + signature = null; + MemoryStream bOut = new MemoryStream(); + int ch; + while ((ch = bcpgIn.ReadByte()) >= 0) + { + bOut.WriteByte((byte) ch); + } + signatureEncoding = bOut.ToArray(); + } + else + { + throw new IOException("unknown signature key algorithm: " + keyAlgorithm); + } + break; + } + } + + /** + * Generate a version 4 signature packet. + * + * @param signatureType + * @param keyAlgorithm + * @param hashAlgorithm + * @param hashedData + * @param unhashedData + * @param fingerprint + * @param signature + */ + public SignaturePacket( + int signatureType, + long keyId, + PublicKeyAlgorithmTag keyAlgorithm, + HashAlgorithmTag hashAlgorithm, + SignatureSubpacket[] hashedData, + SignatureSubpacket[] unhashedData, + byte[] fingerprint, + MPInteger[] signature) + : this(4, signatureType, keyId, keyAlgorithm, hashAlgorithm, hashedData, unhashedData, fingerprint, signature) + { + } + + /** + * Generate a version 2/3 signature packet. + * + * @param signatureType + * @param keyAlgorithm + * @param hashAlgorithm + * @param fingerprint + * @param signature + */ + public SignaturePacket( + int version, + int signatureType, + long keyId, + PublicKeyAlgorithmTag keyAlgorithm, + HashAlgorithmTag hashAlgorithm, + long creationTime, + byte[] fingerprint, + MPInteger[] signature) + : this(version, signatureType, keyId, keyAlgorithm, hashAlgorithm, null, null, fingerprint, signature) + { + this.creationTime = creationTime; + } + + public SignaturePacket( + int version, + int signatureType, + long keyId, + PublicKeyAlgorithmTag keyAlgorithm, + HashAlgorithmTag hashAlgorithm, + SignatureSubpacket[] hashedData, + SignatureSubpacket[] unhashedData, + byte[] fingerprint, + MPInteger[] signature) + { + this.version = version; + this.signatureType = signatureType; + this.keyId = keyId; + this.keyAlgorithm = keyAlgorithm; + this.hashAlgorithm = hashAlgorithm; + this.hashedData = hashedData; + this.unhashedData = unhashedData; + this.fingerprint = fingerprint; + this.signature = signature; + + if (hashedData != null) + { + setCreationTime(); + } + } + + public int Version + { + get { return version; } + } + + public int SignatureType + { + get { return signatureType; } + } + + /** + * return the keyId + * @return the keyId that created the signature. + */ + public long KeyId + { + get { return keyId; } + } + + /** + * return the signature trailer that must be included with the data + * to reconstruct the signature + * + * @return byte[] + */ + public byte[] GetSignatureTrailer() + { + byte[] trailer = null; + + if (version == 3) + { + trailer = new byte[5]; + + long time = creationTime / 1000L; + + trailer[0] = (byte)signatureType; + trailer[1] = (byte)(time >> 24); + trailer[2] = (byte)(time >> 16); + trailer[3] = (byte)(time >> 8); + trailer[4] = (byte)(time); + } + else + { + MemoryStream sOut = new MemoryStream(); + + sOut.WriteByte((byte)this.Version); + sOut.WriteByte((byte)this.SignatureType); + sOut.WriteByte((byte)this.KeyAlgorithm); + sOut.WriteByte((byte)this.HashAlgorithm); + + MemoryStream hOut = new MemoryStream(); + SignatureSubpacket[] hashed = this.GetHashedSubPackets(); + + for (int i = 0; i != hashed.Length; i++) + { + hashed[i].Encode(hOut); + } + + byte[] data = hOut.ToArray(); + + sOut.WriteByte((byte)(data.Length >> 8)); + sOut.WriteByte((byte)data.Length); + sOut.Write(data, 0, data.Length); + + byte[] hData = sOut.ToArray(); + + sOut.WriteByte((byte)this.Version); + sOut.WriteByte((byte)0xff); + sOut.WriteByte((byte)(hData.Length>> 24)); + sOut.WriteByte((byte)(hData.Length >> 16)); + sOut.WriteByte((byte)(hData.Length >> 8)); + sOut.WriteByte((byte)(hData.Length)); + + trailer = sOut.ToArray(); + } + + return trailer; + } + + public PublicKeyAlgorithmTag KeyAlgorithm + { + get { return keyAlgorithm; } + } + + public HashAlgorithmTag HashAlgorithm + { + get { return hashAlgorithm; } + } + + /** + * return the signature as a set of integers - note this is normalised to be the + * ASN.1 encoding of what appears in the signature packet. + */ + public MPInteger[] GetSignature() + { + return signature; + } + + /** + * Return the byte encoding of the signature section. + * @return uninterpreted signature bytes. + */ + public byte[] GetSignatureBytes() + { + if (signatureEncoding != null) + { + return (byte[]) signatureEncoding.Clone(); + } + + MemoryStream bOut = new MemoryStream(); + BcpgOutputStream bcOut = new BcpgOutputStream(bOut); + + foreach (MPInteger sigObj in signature) + { + try + { + bcOut.WriteObject(sigObj); + } + catch (IOException e) + { + throw new Exception("internal error: " + e); + } + } + + return bOut.ToArray(); + } + + public SignatureSubpacket[] GetHashedSubPackets() + { + return hashedData; + } + + public SignatureSubpacket[] GetUnhashedSubPackets() + { + return unhashedData; + } + + /// <summary>Return the creation time in milliseconds since 1 Jan., 1970 UTC.</summary> + public long CreationTime + { + get { return creationTime; } + } + + public override void Encode( + BcpgOutputStream bcpgOut) + { + MemoryStream bOut = new MemoryStream(); + BcpgOutputStream pOut = new BcpgOutputStream(bOut); + + pOut.WriteByte((byte) version); + + if (version == 3 || version == 2) + { + pOut.Write( + 5, // the length of the next block + (byte) signatureType); + + pOut.WriteInt((int)(creationTime / 1000L)); + + pOut.WriteLong(keyId); + + pOut.Write( + (byte) keyAlgorithm, + (byte) hashAlgorithm); + } + else if (version == 4) + { + pOut.Write( + (byte) signatureType, + (byte) keyAlgorithm, + (byte) hashAlgorithm); + + EncodeLengthAndData(pOut, GetEncodedSubpackets(hashedData)); + + EncodeLengthAndData(pOut, GetEncodedSubpackets(unhashedData)); + } + else + { + throw new IOException("unknown version: " + version); + } + + pOut.Write(fingerprint); + + if (signature != null) + { + pOut.WriteObjects(signature); + } + else + { + pOut.Write(signatureEncoding); + } + + bcpgOut.WritePacket(PacketTag.Signature, bOut.ToArray(), true); + } + + private static void EncodeLengthAndData( + BcpgOutputStream pOut, + byte[] data) + { + pOut.WriteShort((short) data.Length); + pOut.Write(data); + } + + private static byte[] GetEncodedSubpackets( + SignatureSubpacket[] ps) + { + MemoryStream sOut = new MemoryStream(); + + foreach (SignatureSubpacket p in ps) + { + p.Encode(sOut); + } + + return sOut.ToArray(); + } + + private void setCreationTime() + { + foreach (SignatureSubpacket p in hashedData) + { + if (p is SignatureCreationTime) + { + creationTime = DateTimeUtilities.DateTimeToUnixMs( + ((SignatureCreationTime)p).GetTime()); + break; + } + } + } + } +} |