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_te;
  
  import ghidra.app.util.bin.BinaryReader;
  import ghidra.app.util.bin.StructConverter;
  import ghidra.program.model.data.ArrayDataType;
  import ghidra.program.model.data.DataType;
  import ghidra.program.model.data.Structure;
  import ghidra.program.model.data.StructureDataType;
  
  import java.io.IOException;
  
  /**
   * Parser for Terse Executable (TE) binaries. TE binaries are a simplified form of PE/COFF
   * executables; fields from the COFF header and optional image headers (including Windows-specific
   * fields) are consolidated into a single header, which has the following fields:
   *
   *   EFI Terse Executable Image Header
   *   +---------------------+------+--------------------------------------------+
   *   | Type                | Size | Description                                |
   *   +---------------------+------+--------------------------------------------+
   *   | char[2]             |    2 | Signature ("VZ")                           |
   *   | u16                 |    2 | Machine Type (same as COFF field)          |
   *   | u8                  |    1 | Number of Sections                         |
   *   | u8                  |    1 | Subsystem (same as Windows-specific field) |
   *   | u16                 |    2 | Stripped Size                              |
   *   | u32                 |    4 | Entry Point Address                        |
   *   | u32                 |    4 | Code Base Address                          |
   *   | u64                 |    8 | Image Base Address                         |
   *   | pe_image_data_dir_t |    8 | Base Relocation Directory (same as PE)     |
   *   | pe_image_data_dir_t |    8 | Debug Directory (same as PE)               |
   *   +---------------------+------+--------------------------------------------+
   *
   * The TE header is immediately followed by an array of section headers; these are standard PE
   * section headers.
   */
  public class TerseExecutableHeader implements StructConverter {
  	// Original header fields
  	private String signature;
  	private short machine;
  	private byte numSections;
  	private byte subsystem;
  	private short strippedSize;
  	private int entryPointAddress;
  	private int codeBase;
  	private long imageBase;
  	private EFIImageDataDirectory baseRelocationDirectory;
  	private EFIImageDataDirectory debugDirectory;
  	private EFIImageSectionHeader[] sectionHeaders;
  
  	/**
  	 * Constructs a TerseExecutableHeader from a specified BinaryReader.
  	 *
  	 * @param reader the specified BinaryReader
  	 */
  	public TerseExecutableHeader(BinaryReader reader) throws IOException {
  		// Read the TE header fields.
  		signature = reader.readNextAsciiString(
  				TerseExecutableConstants.TE_SIGNATURE.length());
  		if (!signature.equals(TerseExecutableConstants.TE_SIGNATURE)) {
  			throw new IOException("Not a valid Terse Executable");
  		}
  
  		machine = reader.readNextShort();
  		numSections = reader.readNextByte();
  		subsystem = reader.readNextByte();
  		strippedSize = reader.readNextShort();
  		entryPointAddress = reader.readNextInt();
  		codeBase = reader.readNextInt();
  		imageBase = reader.readNextLong();
  		baseRelocationDirectory = new EFIImageDataDirectory(reader);
  		debugDirectory = new EFIImageDataDirectory(reader);
  
  		// Parse the section headers.
  		sectionHeaders = new EFIImageSectionHeader[numSections];
  		for (int i = 0; i < numSections; i++) {
  			sectionHeaders[i] = new EFIImageSectionHeader(reader);
  		}
  	}
  
  	/**
  	 * Returns the entry point address in the current TE header.
  	 *
  	 * @return the entry point address in the current TE header
  	 */
  	public int getEntryPointAddress() {
  		return entryPointAddress;
  	}
  
  	/**
  	 * Returns the header offset in the current TE header.
  	 *
  	 * @return the header offset in the current TE header
  	 */
  	public int getHeaderOffset() {
  		return strippedSize - TerseExecutableConstants.TE_HEADER_SIZE;
  	}
  
  	/**
  	 * Returns the image base in the current TE header.
  	 *
  	 * @return the image base in the current TE header
  	 */
  	public long getImageBase() {
  		return imageBase;
  	}
  
  	/**
  	 * Returns the machine type in the current TE header.
  	 *
  	 * @return the machine type in the current TE header
  	 */
  	public short getMachineType() {
  		return machine;
  	}
  
  	/**
  	 * Returns the number of sections in the current TE header.
  	 *
  	 * @return the number of sections in the current TE header
  	 */
  	public byte getNumSections() {
  		return numSections;
  	}
  
  	/**
  	 * Returns the section headers in the current TE header.
  	 *
  	 * @return the section headers in the current TE header
  	 */
  	public EFIImageSectionHeader[] getSections() {
  		return sectionHeaders;
  	}
  
  	/**
  	 * Returns the subsystem in the current TE header.
  	 *
  	 * @return the subsystem in the current TE header.
  	 */
  	public short getSubsystem() {
  		return subsystem;
  	}
  
  	@Override
  	public DataType toDataType() {
  		Structure structure = new StructureDataType("efi_image_te_hdr_t", 0);
  		structure.add(new ArrayDataType(ASCII, TerseExecutableConstants.TE_SIGNATURE.length(), 1),
  				"signature", null);
  		structure.add(WORD, 2, "machine", null);
  		structure.add(BYTE, 1, "num_sections", null);
  		structure.add(BYTE, 1, "subsystem", null);
  		structure.add(WORD, 2, "stripped_size", null);
  		structure.add(DWORD, 4, "entry_point_addr", null);
  		structure.add(DWORD, 4, "code_base", null);
  		structure.add(QWORD, 8, "image_base", null);
  		structure.add(baseRelocationDirectory.toDataType(), "base_relocation_data_dir", null);
  		structure.add(debugDirectory.toDataType(), "debug_data_dir", null);
  		return structure;
  	}
  }
  