/// <summary> /// Process extra data fields updating the entry based on the contents. /// </summary> /// <param name="localHeader">True if the extra data fields should be handled /// for a local header, rather than for a central header. /// </param> internal void ProcessExtraData(bool localHeader) { ZipExtraData extraData = new ZipExtraData(this.extra); if ( extraData.Find(0x0001) ) { if ( (versionToExtract & 0xff) < ZipConstants.VersionZip64 ) { throw new ZipException("Zip64 Extended information found but version is not valid"); } // The recorded size will change but remember that this is zip64. forceZip64_ = true; if ( extraData.ValueLength < 4 ) { throw new ZipException("Extra data extended Zip64 information length is invalid"); } if ( localHeader || (size == uint.MaxValue) ) { size = (ulong)extraData.ReadLong(); } if ( localHeader || (compressedSize == uint.MaxValue) ) { compressedSize = (ulong)extraData.ReadLong(); } if ( !localHeader && (offset == uint.MaxValue) ) { offset = extraData.ReadLong(); } } else { if ( ((versionToExtract & 0xff) >= ZipConstants.VersionZip64) && ((size == uint.MaxValue) || (compressedSize == uint.MaxValue)) ) { throw new ZipException("Zip64 Extended information required but is missing."); } } if ( extraData.Find(10) ) { // No room for any tags. if ( extraData.ValueLength < 8 ) { throw new ZipException("NTFS Extra data invalid"); } extraData.ReadInt(); // Reserved while ( extraData.UnreadCount >= 4 ) { int ntfsTag = extraData.ReadShort(); int ntfsLength = extraData.ReadShort(); if ( ntfsTag == 1 ) { if ( ntfsLength >= 24 ) { long lastModification = extraData.ReadLong(); long lastAccess = extraData.ReadLong(); long createTime = extraData.ReadLong(); DateTime = System.DateTime.FromFileTime(lastModification); } break; } else { // An unknown NTFS tag so simply skip it. extraData.Skip(ntfsLength); } } } else if ( extraData.Find(0x5455) ) { int length = extraData.ValueLength; int flags = extraData.ReadByte(); // Can include other times but these are ignored. Length of data should // actually be 1 + 4 * no of bits in flags. if ( ((flags & 1) != 0) && (length >= 5) ) { int iTime = extraData.ReadInt(); DateTime = (new System.DateTime ( 1970, 1, 1, 0, 0, 0 ).ToUniversalTime() + new TimeSpan ( 0, 0, 0, iTime, 0 )).ToLocalTime(); } } }
/// <summary> /// Process extra data fields updating the entry based on the contents. /// </summary> /// <param name="localHeader">True if the extra data fields should be handled /// for a local header, rather than for a central header. /// </param> internal void ProcessExtraData(bool localHeader) { ZipExtraData extraData = new ZipExtraData(this.extra); if (extraData.Find(0x0001)) { if ((versionToExtract & 0xff) < ZipConstants.VersionZip64) { throw new ZipException("Zip64 Extended information found but version is not valid"); } // The recorded size will change but remember that this is zip64. forceZip64_ = true; if (extraData.ValueLength < 4) { throw new ZipException("Extra data extended Zip64 information length is invalid"); } if (localHeader || (size == uint.MaxValue)) { size = (ulong)extraData.ReadLong(); } if (localHeader || (compressedSize == uint.MaxValue)) { compressedSize = (ulong)extraData.ReadLong(); } if (!localHeader && (offset == uint.MaxValue)) { offset = extraData.ReadLong(); } } else { if ( ((versionToExtract & 0xff) >= ZipConstants.VersionZip64) && ((size == uint.MaxValue) || (compressedSize == uint.MaxValue)) ) { throw new ZipException("Zip64 Extended information required but is missing."); } } if (extraData.Find(10)) { // No room for any tags. if (extraData.ValueLength < 8) { throw new ZipException("NTFS Extra data invalid"); } extraData.ReadInt(); // Reserved while (extraData.UnreadCount >= 4) { int ntfsTag = extraData.ReadShort(); int ntfsLength = extraData.ReadShort(); if (ntfsTag == 1) { if (ntfsLength >= 24) { long lastModification = extraData.ReadLong(); long lastAccess = extraData.ReadLong(); long createTime = extraData.ReadLong(); DateTime = System.DateTime.FromFileTime(lastModification); } break; } else { // An unknown NTFS tag so simply skip it. extraData.Skip(ntfsLength); } } } else if (extraData.Find(0x5455)) { int length = extraData.ValueLength; int flags = extraData.ReadByte(); // Can include other times but these are ignored. Length of data should // actually be 1 + 4 * no of bits in flags. if (((flags & 1) != 0) && (length >= 5)) { int iTime = extraData.ReadInt(); DateTime = (new System.DateTime(1970, 1, 1, 0, 0, 0).ToUniversalTime() + new TimeSpan(0, 0, 0, iTime, 0)).ToLocalTime(); } } }