content: /* ###
   * IP: GHIDRA
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package firmware.uefi_fv;
  
  import java.io.IOException;
  import java.util.Formatter;
  
  import ghidra.app.util.bin.BinaryReader;
  import ghidra.app.util.bin.ByteProvider;
  import ghidra.app.util.bin.ByteProviderWrapper;
  import ghidra.formats.gfilesystem.fileinfo.FileAttributeType;
  import ghidra.formats.gfilesystem.fileinfo.FileAttributes;
  
  /**
   * Parser for the common FFS section header, which has the following fields:
   *
   * <pre>
   *   Common UEFI FFS Section Header
   *   +------+------+----------------------------------------+
   *   | Type | Size | Description                            |
   *   +------+------+----------------------------------------+
   *   | u24  |    3 | Size (0xFFFFFF for FFSv3 large files)  |
   *   | u8   |    1 | Type                                   |
   *   | u32  |    4 | Extended Size (FFSv3 large files only) |
   *   +------+------+----------------------------------------+
   * </pre>
   *
   * Subclasses will parse additional fields for specific FFS section types.
   */
  public abstract class FFSSection implements UEFIFile {
  	// Original header fields
  	private int size;
  	private final byte type;
  
  	private final long baseIndex;
  	private boolean hasExtendedSize;
  	private final ByteProvider provider;
  
  	/**
  	 * Constructs a UEFIFFSFile from a specified BinaryReader.
  	 *
  	 * @param reader the specified BinaryReader
  	 */
  	public FFSSection(BinaryReader reader) throws IOException {
  		baseIndex = reader.getPointerIndex();
  		byte[] sizeBytes = reader.readNextByteArray(3);
  		size = ((sizeBytes[2] & 0xFF) << 16 | (sizeBytes[1] & 0xFF) << 8 | sizeBytes[0] & 0xFF);
  		type = reader.readNextByte();
  
  		if (size == 0xFFFFFF) {
  			hasExtendedSize = true;
  			size = reader.readNextInt() - 4;
  		}
  
  		size -= UEFIFFSConstants.FFS_SECTION_HEADER_SIZE;
  		provider = new ByteProviderWrapper(reader.getByteProvider(), reader.getPointerIndex(), length());
  	}
  
  	/**
  	 * Returns a ByteProvider for the contents of the current FFS section. Subclasses of FFSSection may override this
  	 * as needed.
  	 *
  	 * @return a ByteProvider for the contents of the current FFS section
  	 */
  	public ByteProvider getByteProvider() {
  		return provider;
  	}
  
  	/**
  	 * Returns the length of the header for the current FFS section.
  	 *
  	 * @return the length of the header for the current FFS section
  	 */
  	public int getHeaderLength() {
  		int headerLength = UEFIFFSConstants.FFS_SECTION_HEADER_SIZE;
  		if (hasExtendedSize) {
  			headerLength += 4;
  		}
  
  		return headerLength;
  	}
  
  	/**
  	 * Returns the total length of the current FFS section.
  	 *
  	 * @return the total length of the current FFS section
  	 */
  	public int getTotalLength() {
  		return getHeaderLength() + (int) length();
  	}
  
  	/**
  	 * Returns the name of the current FFS section.
  	 *
  	 * @return the name of the current FFS section
  	 */
  	@Override
  	public String getName() {
  		return UEFIFFSConstants.SectionType.toString(type);
  	}
  
  	/**
  	 * Returns the type for the current FFS section.
  	 *
  	 * @return the type for the current FFS section
  	 */
  	public byte getType() {
  		return type;
  	}
  
  	/**
  	 * Returns the length of the body in the current FFS section.
  	 *
  	 * @return the length of the body in the current FFS section
  	 */
  	@Override
  	public long length() {
  		return size;
  	}
  
  	/**
  	 * Returns FileAttributes for the current FFS section.
  	 *
  	 * @return FileAttributes for the current FFS section
  	 */
  	public FileAttributes getFileAttributes() {
  		FileAttributes attributes = new FileAttributes();
  		attributes.add(FileAttributeType.NAME_ATTR, getName());
  		attributes.add(FileAttributeType.SIZE_ATTR, Long.valueOf(length()));
  		attributes.add("Base", String.format("%#x", baseIndex));
  		attributes.add("Section Type", UEFIFFSConstants.SectionType.toString(type));
  		attributes.add("Header Size", getHeaderLength());
  		return attributes;
  	}
  }
  