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Diffstat (limited to 'Emby.Server.Implementations/Cryptography/ASN1Convert.cs')
| -rw-r--r-- | Emby.Server.Implementations/Cryptography/ASN1Convert.cs | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/Emby.Server.Implementations/Cryptography/ASN1Convert.cs b/Emby.Server.Implementations/Cryptography/ASN1Convert.cs new file mode 100644 index 000000000..851d36dc7 --- /dev/null +++ b/Emby.Server.Implementations/Cryptography/ASN1Convert.cs @@ -0,0 +1,207 @@ +// +// ASN1Convert.cs: Abstract Syntax Notation 1 convertion routines +// +// Authors: +// Sebastien Pouliot <sebastien@ximian.com> +// Jesper Pedersen <jep@itplus.dk> +// +// (C) 2003 Motus Technologies Inc. (http://www.motus.com) +// (C) 2004 IT+ A/S (http://www.itplus.dk) +// Copyright (C) 2004-2007 Novell, Inc (http://www.novell.com) +// +// Permission is hereby granted, free of charge, to any person obtaining +// a copy of this software and associated documentation files (the +// "Software"), to deal in the Software without restriction, including +// without limitation the rights to use, copy, modify, merge, publish, +// distribute, sublicense, and/or sell copies of the Software, and to +// permit persons to whom the Software is furnished to do so, subject to +// the following conditions: +// +// The above copyright notice and this permission notice shall be +// included in all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE +// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +// + +using System; +using System.Globalization; +using System.Security.Cryptography; +using System.Text; + +namespace Emby.Server.Core.Cryptography +{ + + // References: + // a. ITU ASN.1 standards (free download) + // http://www.itu.int/ITU-T/studygroups/com17/languages/ + + public static class ASN1Convert { + // RFC3280, section 4.2.1.5 + // CAs conforming to this profile MUST always encode certificate + // validity dates through the year 2049 as UTCTime; certificate validity + // dates in 2050 or later MUST be encoded as GeneralizedTime. + + // Under 1.x this API requires a Local datetime to be provided + // Under 2.0 it will also accept a Utc datetime + static public ASN1 FromDateTime (DateTime dt) + { + if (dt.Year < 2050) { + // UTCTIME + return new ASN1 (0x17, Encoding.ASCII.GetBytes ( + dt.ToUniversalTime ().ToString ("yyMMddHHmmss", + CultureInfo.InvariantCulture) + "Z")); + } + else { + // GENERALIZEDTIME + return new ASN1 (0x18, Encoding.ASCII.GetBytes ( + dt.ToUniversalTime ().ToString ("yyyyMMddHHmmss", + CultureInfo.InvariantCulture) + "Z")); + } + } + + static public ASN1 FromInt32 (Int32 value) + { + byte[] integer = BitConverterLE.GetBytes (value); + Array.Reverse (integer); + int x = 0; + while ((x < integer.Length) && (integer [x] == 0x00)) + x++; + ASN1 asn1 = new ASN1 (0x02); + switch (x) { + case 0: + asn1.Value = integer; + break; + case 4: + asn1.Value = new byte [1]; + break; + default: + byte[] smallerInt = new byte [4 - x]; + Buffer.BlockCopy (integer, x, smallerInt, 0, smallerInt.Length); + asn1.Value = smallerInt; + break; + } + return asn1; + } + + static public ASN1 FromOid (string oid) + { + if (oid == null) + throw new ArgumentNullException ("oid"); + + return new ASN1 (CryptoConfig.EncodeOID (oid)); + } + + static public ASN1 FromUnsignedBigInteger (byte[] big) + { + if (big == null) + throw new ArgumentNullException ("big"); + + // check for numbers that could be interpreted as negative (first bit) + if (big [0] >= 0x80) { + // in thie cas we add a new, empty, byte (position 0) so we're + // sure this will always be interpreted an unsigned integer. + // However we can't feed it into RSAParameters or DSAParameters + int length = big.Length + 1; + byte[] uinteger = new byte [length]; + Buffer.BlockCopy (big, 0, uinteger, 1, length - 1); + big = uinteger; + } + return new ASN1 (0x02, big); + } + + static public int ToInt32 (ASN1 asn1) + { + if (asn1 == null) + throw new ArgumentNullException ("asn1"); + if (asn1.Tag != 0x02) + throw new FormatException ("Only integer can be converted"); + + int x = 0; + for (int i=0; i < asn1.Value.Length; i++) + x = (x << 8) + asn1.Value [i]; + return x; + } + + // Convert a binary encoded OID to human readable string representation of + // an OID (IETF style). Based on DUMPASN1.C from Peter Gutmann. + static public string ToOid (ASN1 asn1) + { + if (asn1 == null) + throw new ArgumentNullException ("asn1"); + + byte[] aOID = asn1.Value; + StringBuilder sb = new StringBuilder (); + // Pick apart the OID + byte x = (byte) (aOID[0] / 40); + byte y = (byte) (aOID[0] % 40); + if (x > 2) { + // Handle special case for large y if x = 2 + y += (byte) ((x - 2) * 40); + x = 2; + } + sb.Append (x.ToString (CultureInfo.InvariantCulture)); + sb.Append ("."); + sb.Append (y.ToString (CultureInfo.InvariantCulture)); + ulong val = 0; + for (x = 1; x < aOID.Length; x++) { + val = ((val << 7) | ((byte) (aOID [x] & 0x7F))); + if ( !((aOID [x] & 0x80) == 0x80)) { + sb.Append ("."); + sb.Append (val.ToString (CultureInfo.InvariantCulture)); + val = 0; + } + } + return sb.ToString (); + } + + static public DateTime ToDateTime (ASN1 time) + { + if (time == null) + throw new ArgumentNullException ("time"); + + string t = Encoding.ASCII.GetString (time.Value); + // to support both UTCTime and GeneralizedTime (and not so common format) + string mask = null; + int year; + switch (t.Length) { + case 11: + // illegal format, still it's supported for compatibility + mask = "yyMMddHHmmZ"; + break; + case 13: + // RFC3280: 4.1.2.5.1 UTCTime + year = Convert.ToInt16 (t.Substring (0, 2), CultureInfo.InvariantCulture); + // Where YY is greater than or equal to 50, the + // year SHALL be interpreted as 19YY; and + // Where YY is less than 50, the year SHALL be + // interpreted as 20YY. + if (year >= 50) + t = "19" + t; + else + t = "20" + t; + mask = "yyyyMMddHHmmssZ"; + break; + case 15: + mask = "yyyyMMddHHmmssZ"; // GeneralizedTime + break; + case 17: + // another illegal format (990630000000+1000), again supported for compatibility + year = Convert.ToInt16 (t.Substring (0, 2), CultureInfo.InvariantCulture); + string century = (year >= 50) ? "19" : "20"; + // ASN.1 (see ITU X.680 section 43.3) deals with offset differently than .NET + char sign = (t[12] == '+') ? '-' : '+'; + t = String.Format ("{0}{1}{2}{3}{4}:{5}{6}", century, t.Substring (0, 12), sign, + t[13], t[14], t[15], t[16]); + mask = "yyyyMMddHHmmsszzz"; + break; + } + return DateTime.ParseExact (t, mask, CultureInfo.InvariantCulture, DateTimeStyles.AdjustToUniversal); + } + } +} |