Package ghidra.app.util.bin.format.elf

Class ElfProgramHeader

java.lang.Object
ghidra.app.util.bin.format.elf.ElfProgramHeader
All Implemented Interfaces:
MemoryLoadable, StructConverter, Comparable<ElfProgramHeader>
public class ElfProgramHeader extends Object implements StructConverter, Comparable<ElfProgramHeader>, MemoryLoadable
An executable or shared object file's program header table is an array of structures, each describing a segment or other information the system needs to prepare the program for execution. An object file segment contains one or more sections. Program headers are meaningful only for executable and shared object files. A file specifies its own program header size with the ELF header's e_phentsize and e_phnum members. Some entries describe process segments; others give supplementary information and do not contribute to the process image. Segment entries may appear in any order. Except for PT_LOAD segment entries which must appear in ascending order, sorted on the p_vaddr member. 
 typedef struct {
     Elf32_Word   p_type;
     Elf32_Off    p_offset;
     Elf32_Addr   p_vaddr;
     Elf32_Addr   p_paddr;
     Elf32_Word   p_filesz;
     Elf32_Word   p_memsz;
     Elf32_Word   p_flags;
     Elf32_Word   p_align;
 } Elf32_Phdr;
 
 typedef struct {
     Elf64_Word   p_type;         //Segment type
     Elf64_Word   p_flags;        //Segment flags
     Elf64_Off    p_offset;       //Segment file offset
     Elf64_Addr   p_vaddr;        //Segment virtual address
     Elf64_Addr   p_paddr;        //Segment physical address
     Elf64_Xword  p_filesz;       //Segment size in file
     Elf64_Xword  p_memsz;        //Segment size in memory
     Elf64_Xword  p_align;        //Segment alignment
 } Elf64_Phdr;

  • Field Details

  • Constructor Details

    • ElfProgramHeader

      public ElfProgramHeader(BinaryReader reader, ElfHeader header) throws IOException
      Construct ElfProgramHeader
      Parameters:
      reader - dedicated reader instance positioned to the start of the program header data. (the reader supplied will be retained and altered).
      header - ELF header
      Throws:
      IOException - if an IO error occurs during parse

  • Method Details

    • getElfHeader

      public ElfHeader getElfHeader()
      Return ElfHeader associated with this program header
      Returns:
      ElfHeader

    • getTypeAsString

      public String getTypeAsString()
      Get header type as string. ElfProgramHeaderType name will be returned if know, otherwise a numeric name of the form "PT_0x12345678" will be returned.
      Returns:
      header type as string

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • getDescription

      public String getDescription()
      Get header description
      Returns:
      header description

    • getComment

      public String getComment()
      Get descriptive comment which includes type and description
      Returns:
      descriptive comment

    • getAlign

      public long getAlign()
      As ''Program Loading'' later in this part describes, loadable process segments must have congruent values for p_vaddr and p_offset, modulo the page size. This member gives the value to which the segments are aligned in memory and in the file. Values 0 and 1 mean no alignment is required. Otherwise, p_align should be a positive, integral power of 2, and p_vaddr should equal p_offset, modulo p_align.
      Returns:
      the segment alignment value

    • getFileSize

      public long getFileSize()
      This member gives the number of bytes in the file image of the segment; it may be zero.
      Returns:
      the number of bytes in the file image

    • getFlags

      public int getFlags()
      This member gives flags relevant to the segment. Defined flag values appear below.
      Returns:
      the segment flags

    • isRead

      public boolean isRead()
      Returns true if this segment is readable when loaded
      Returns:
      true if this segment is readable when loaded

    • isWrite

      public boolean isWrite()
      Returns true if this segment is writable when loaded
      Returns:
      true if this segment is writable when loaded

    • isExecute

      public boolean isExecute()
      Returns true if this segment is executable when loaded
      Returns:
      true if this segment is executable when loaded

    • getMemorySize

      public long getMemorySize()
      Get the unadjusted memory size in bytes specified by this program header; it may be zero.
      Returns:
      the unadjusted memory size in bytes specified by this program header

    • getAdjustedMemorySize

      public long getAdjustedMemorySize()
      Get the adjusted memory size in bytes of the memory block which relates to this program header; it may be zero if no block should be created. The returned value reflects any adjustment the ElfExtension may require based upon the specific processor/language implementation which may require filtering of file bytes as loaded into memory.
      Returns:
      the number of bytes in the resulting memory block

    • getAdjustedLoadSize

      public long getAdjustedLoadSize()
      Get the adjusted file load size (i.e., filtered load size) to be loaded into memory block which relates to this program header; it may be zero if no block should be created. The returned value reflects any adjustment the ElfExtension may require based upon the specific processor/language implementation which may require filtering of file bytes as loaded into memory.
      Returns:
      the number of bytes to be loaded into the resulting memory block

    • hasFilteredLoadInputStream

      public boolean hasFilteredLoadInputStream(ElfLoadHelper elfLoadHelper, Address start)
      Description copied from interface: MemoryLoadable
      Determine if the use of input stream decompression or filtering via an extension is neccessary. If this method returns true and a filtered stream is required and will prevent the use of a direct mapping to file bytes for affected memory regions.
      Specified by:
      hasFilteredLoadInputStream in interface MemoryLoadable
      Parameters:
      elfLoadHelper - ELF load helper
      start - memory load address
      Returns:
      true if the use of a filtered input stream is required

    • getFilteredLoadInputStream

      public InputStream getFilteredLoadInputStream(ElfLoadHelper elfLoadHelper, Address start, long dataLength, BiConsumer<String,Throwable> errorConsumer) throws IOException
      Description copied from interface: MemoryLoadable
      Return filtered InputStream for loading a memory block (includes non-loaded OTHER blocks). See MemoryLoadable.hasFilteredLoadInputStream(ElfLoadHelper, Address).
      Specified by:
      getFilteredLoadInputStream in interface MemoryLoadable
      Parameters:
      elfLoadHelper - ELF load helper
      start - memory load address
      dataLength - the in-memory data length in bytes (actual bytes read from dataInput may be more)
      errorConsumer - consumer that will accept errors which may occur during stream decompression, if null Msg.error() will be used.
      Returns:
      filtered input stream or original input stream
      Throws:
      IOException - if error initializing filtered input stream

    • getRawInputStream

      public InputStream getRawInputStream() throws IOException
      Description copied from interface: MemoryLoadable
      Returns raw data input stream associated with this loadable object..
      Specified by:
      getRawInputStream in interface MemoryLoadable
      Returns:
      raw data input stream associated with this loadable object.
      Throws:
      IOException - if error initializing input stream

    • getReader

      public BinaryReader getReader()
      Returns the binary reader.
      Returns:
      the binary reader

    • getOffset

      public long getOffset()
      This member gives the offset from the beginning of the file at which the first byte of the segment resides.
      Returns:
      the offset from the beginning of the file

    • isInvalidOffset

      public boolean isInvalidOffset()
      Return true if this program header's offset is invalid.
      Returns:
      true if this program header's offset is invalid

    • getOffset

      public long getOffset(long virtualAddress)
      Compute the file offset associated with the specified loaded virtual address defined by this PT_LOAD program header. This can be useful when attempting to locate addresses defined by the PT_DYNAMIC section.
      Parameters:
      virtualAddress - a memory address which has already had the PRElink adjustment applied
      Returns:
      computed file offset or -1 if virtual address not contained within this header
      See Also:

    • getPhysicalAddress

      public long getPhysicalAddress()
      On systems for which physical addressing is relevant, this member is reserved for the segment's physical address. Because System V ignores physical addressing for application programs, this member has unspecified contents for executable files and shared objects.
      Returns:
      the segment's physical address

    • getType

      public int getType()
      This member tells what kind of segment this array element describes or how to interpret the array element's information. Type values and their meanings appear below.
      Returns:
      the program header type

    • getVirtualAddress

      public long getVirtualAddress()
      This member gives the virtual address at which the first byte of the segment resides in memory.
      Returns:
      the virtual address

    • toDataType

      public DataType toDataType()
      Description copied from interface: StructConverter
      Returns a structure datatype representing the contents of the implementor of this interface.

      For example, given: 

       class A {
     int foo;
     double bar;
 }

      The return value should be a structure data type with two data type components; an INT and a DOUBLE. The structure should contain field names and, if possible, field comments.

      Specified by:
      toDataType in interface StructConverter
      Returns:
      returns a structure datatype representing the implementor of this interface
      See Also:

    • compareTo

      public int compareTo(ElfProgramHeader that)
      Specified by:
      compareTo in interface Comparable<ElfProgramHeader>

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object