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Diffstat (limited to 'crypto/src/asn1/DerObjectIdentifier.cs')
| -rw-r--r-- | crypto/src/asn1/DerObjectIdentifier.cs | 347 |
1 files changed, 347 insertions, 0 deletions
diff --git a/crypto/src/asn1/DerObjectIdentifier.cs b/crypto/src/asn1/DerObjectIdentifier.cs new file mode 100644 index 000000000..f9f6a79d6 --- /dev/null +++ b/crypto/src/asn1/DerObjectIdentifier.cs @@ -0,0 +1,347 @@ +using System; +using System.IO; +using System.Text; +using System.Text.RegularExpressions; + +using Org.BouncyCastle.Math; +using Org.BouncyCastle.Utilities; + +namespace Org.BouncyCastle.Asn1 +{ + public class DerObjectIdentifier + : Asn1Object + { + private readonly string identifier; + + private byte[] body = null; + + /** + * return an Oid from the passed in object + * + * @exception ArgumentException if the object cannot be converted. + */ + public static DerObjectIdentifier GetInstance(object obj) + { + if (obj == null || obj is DerObjectIdentifier) + return (DerObjectIdentifier) obj; + if (obj is byte[]) + return FromOctetString((byte[])obj); + throw new ArgumentException("illegal object in GetInstance: " + obj.GetType().Name, "obj"); + } + + /** + * return an object Identifier from a tagged object. + * + * @param obj the tagged object holding the object we want + * @param explicitly true if the object is meant to be explicitly + * tagged false otherwise. + * @exception ArgumentException if the tagged object cannot + * be converted. + */ + public static DerObjectIdentifier GetInstance( + Asn1TaggedObject obj, + bool explicitly) + { + return GetInstance(obj.GetObject()); + } + + public DerObjectIdentifier( + string identifier) + { + if (identifier == null) + throw new ArgumentNullException("identifier"); + if (!IsValidIdentifier(identifier)) + throw new FormatException("string " + identifier + " not an OID"); + + this.identifier = identifier; + } + + internal DerObjectIdentifier(DerObjectIdentifier oid, string branchID) + { + if (!IsValidBranchID(branchID, 0)) + throw new ArgumentException("string " + branchID + " not a valid OID branch", "branchID"); + + this.identifier = oid.Id + "." + branchID; + } + + // TODO Change to ID? + public string Id + { + get { return identifier; } + } + + public virtual DerObjectIdentifier Branch(string branchID) + { + return new DerObjectIdentifier(this, branchID); + } + + /** + * Return true if this oid is an extension of the passed in branch, stem. + * @param stem the arc or branch that is a possible parent. + * @return true if the branch is on the passed in stem, false otherwise. + */ + public virtual bool On(DerObjectIdentifier stem) + { + string id = Id, stemId = stem.Id; + return id.Length > stemId.Length && id[stemId.Length] == '.' && id.StartsWith(stemId); + } + + internal DerObjectIdentifier(byte[] bytes) + { + this.identifier = MakeOidStringFromBytes(bytes); + this.body = Arrays.Clone(bytes); + } + + private void WriteField( + Stream outputStream, + long fieldValue) + { + byte[] result = new byte[9]; + int pos = 8; + result[pos] = (byte)(fieldValue & 0x7f); + while (fieldValue >= (1L << 7)) + { + fieldValue >>= 7; + result[--pos] = (byte)((fieldValue & 0x7f) | 0x80); + } + outputStream.Write(result, pos, 9 - pos); + } + + private void WriteField( + Stream outputStream, + BigInteger fieldValue) + { + int byteCount = (fieldValue.BitLength + 6) / 7; + if (byteCount == 0) + { + outputStream.WriteByte(0); + } + else + { + BigInteger tmpValue = fieldValue; + byte[] tmp = new byte[byteCount]; + for (int i = byteCount-1; i >= 0; i--) + { + tmp[i] = (byte) ((tmpValue.IntValue & 0x7f) | 0x80); + tmpValue = tmpValue.ShiftRight(7); + } + tmp[byteCount-1] &= 0x7f; + outputStream.Write(tmp, 0, tmp.Length); + } + } + + private void DoOutput(MemoryStream bOut) + { + OidTokenizer tok = new OidTokenizer(identifier); + + string token = tok.NextToken(); + int first = int.Parse(token) * 40; + + token = tok.NextToken(); + if (token.Length <= 18) + { + WriteField(bOut, first + Int64.Parse(token)); + } + else + { + WriteField(bOut, new BigInteger(token).Add(BigInteger.ValueOf(first))); + } + + while (tok.HasMoreTokens) + { + token = tok.NextToken(); + if (token.Length <= 18) + { + WriteField(bOut, Int64.Parse(token)); + } + else + { + WriteField(bOut, new BigInteger(token)); + } + } + } + + internal byte[] GetBody() + { + lock (this) + { + if (body == null) + { + MemoryStream bOut = new MemoryStream(); + DoOutput(bOut); + body = bOut.ToArray(); + } + } + + return body; + } + + internal override void Encode( + DerOutputStream derOut) + { + derOut.WriteEncoded(Asn1Tags.ObjectIdentifier, GetBody()); + } + + protected override int Asn1GetHashCode() + { + return identifier.GetHashCode(); + } + + protected override bool Asn1Equals( + Asn1Object asn1Object) + { + DerObjectIdentifier other = asn1Object as DerObjectIdentifier; + + if (other == null) + return false; + + return this.identifier.Equals(other.identifier); + } + + public override string ToString() + { + return identifier; + } + + private static bool IsValidBranchID( + String branchID, int start) + { + bool periodAllowed = false; + + int pos = branchID.Length; + while (--pos >= start) + { + char ch = branchID[pos]; + + // TODO Leading zeroes? + if ('0' <= ch && ch <= '9') + { + periodAllowed = true; + continue; + } + + if (ch == '.') + { + if (!periodAllowed) + return false; + + periodAllowed = false; + continue; + } + + return false; + } + + return periodAllowed; + } + + private static bool IsValidIdentifier(string identifier) + { + if (identifier.Length < 3 || identifier[1] != '.') + return false; + + char first = identifier[0]; + if (first < '0' || first > '2') + return false; + + return IsValidBranchID(identifier, 2); + } + + private const long LONG_LIMIT = (long.MaxValue >> 7) - 0x7f; + + private static string MakeOidStringFromBytes( + byte[] bytes) + { + StringBuilder objId = new StringBuilder(); + long value = 0; + BigInteger bigValue = null; + bool first = true; + + for (int i = 0; i != bytes.Length; i++) + { + int b = bytes[i]; + + if (value <= LONG_LIMIT) + { + value += (b & 0x7f); + if ((b & 0x80) == 0) // end of number reached + { + if (first) + { + if (value < 40) + { + objId.Append('0'); + } + else if (value < 80) + { + objId.Append('1'); + value -= 40; + } + else + { + objId.Append('2'); + value -= 80; + } + first = false; + } + + objId.Append('.'); + objId.Append(value); + value = 0; + } + else + { + value <<= 7; + } + } + else + { + if (bigValue == null) + { + bigValue = BigInteger.ValueOf(value); + } + bigValue = bigValue.Or(BigInteger.ValueOf(b & 0x7f)); + if ((b & 0x80) == 0) + { + if (first) + { + objId.Append('2'); + bigValue = bigValue.Subtract(BigInteger.ValueOf(80)); + first = false; + } + + objId.Append('.'); + objId.Append(bigValue); + bigValue = null; + value = 0; + } + else + { + bigValue = bigValue.ShiftLeft(7); + } + } + } + + return objId.ToString(); + } + + private static readonly DerObjectIdentifier[] cache = new DerObjectIdentifier[1024]; + + internal static DerObjectIdentifier FromOctetString(byte[] enc) + { + int hashCode = Arrays.GetHashCode(enc); + int first = hashCode & 1023; + + lock (cache) + { + DerObjectIdentifier entry = cache[first]; + if (entry != null && Arrays.AreEqual(enc, entry.GetBody())) + { + return entry; + } + + return cache[first] = new DerObjectIdentifier(enc); + } + } + } +} |