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

Class ElfRelocationContext<H extends ElfRelocationHandler>

java.lang.Object
ghidra.app.util.bin.format.elf.relocation.ElfRelocationContext<H>
Type Parameters:
H - ELF relocation handler class
public class ElfRelocationContext<H extends ElfRelocationHandler> extends Object
ElfRelocationContext provides a relocation handler context related to the processing of entries contained within a specific relocation table.

  • Field Details

  • Constructor Details

    • ElfRelocationContext

      protected ElfRelocationContext(H handler, ElfLoadHelper loadHelper, Map<ElfSymbol,Address> symbolMap)
      Relocation context for a specific Elf image and relocation table
      Parameters:
      handler - relocation handler or null if not available
      loadHelper - the elf load helper
      symbolMap - Elf symbol placement map

  • Method Details

    • startRelocationTableProcessing

      public void startRelocationTableProcessing(ElfRelocationTable relocTable)
      Invoked at start of relocation processing for specified table. The method endRelocationTableProcessing() will be invoked after last relocation is processed.
      Parameters:
      relocTable - relocation table

    • endRelocationTableProcessing

      public void endRelocationTableProcessing()
      Invoked at end of relocation processing for current relocation table. See startRelocationTableProcessing(ElfRelocationTable).

    • processRelocation

      public final RelocationResult processRelocation(ElfRelocation relocation, Address relocationAddress)
      Process a relocation from the relocation table which corresponds to this context. All relocation entries will be processed in the order they appear within the table.
      Parameters:
      relocation - relocation to be processed
      relocationAddress - relocation address where it should be applied
      Returns:
      applied relocation result

    • processRelocation

      protected RelocationResult processRelocation(ElfRelocation relocation, ElfSymbol elfSymbol, Address relocationAddress) throws MemoryAccessException, NotFoundException
      Process a relocation from the relocation table which corresponds to this context after preliminary checks have been performed and ELF symbol resolved. All relocation entries will be processed in the order they appear within the table.
      Parameters:
      relocation - relocation to be processed
      elfSymbol - resolved ELF symbol (not null)
      relocationAddress - relocation address where it should be applied
      Returns:
      applied relocation result
      Throws:
      MemoryAccessException - if a memory access error occurs
      NotFoundException - NOTE: use of this exception is deprecated and should not be thrown

    • markRelocationError

      public final void markRelocationError(Address relocationAddress, int typeId, int symbolIndex, String symbolName, String msg)
      Generate relocation error log entry and bookmark.
      Parameters:
      relocationAddress - relocation address
      typeId - relocation type ID value (will get mapped to ElfRelocationType.name() if possible).
      symbolIndex - associated symbol index within symbol table (-1 to ignore)
      symbolName - relocation symbol name or null if unknown
      msg - error message

    • getRelrRelocationType

      public int getRelrRelocationType()
      Get the RELR relocation type associated with the underlying relocation handler.
      Returns:
      RELR relocation type or 0 if not supported

    • getRelocationContext

      public static ElfRelocationContext<?> getRelocationContext(ElfLoadHelper loadHelper, Map<ElfSymbol,Address> symbolMap)
      Get a relocation context for a specfic Elf image and relocation table
      Parameters:
      loadHelper - Elf load helper
      symbolMap - Elf symbol placement map
      Returns:
      relocation context object. A generic context will be returned if a custom one is not defined.

    • hasRelocationHandler

      public final boolean hasRelocationHandler()
      Returns:
      true if a relocation handler was found

    • getImageBaseWordAdjustmentOffset

      public long getImageBaseWordAdjustmentOffset()
      Get image base addressable word adjustment value to be applied to any pre-linked address values such as those contained with the dynamic table. (Applies to default address space only)
      Returns:
      image base adjustment value

    • extractAddend

      public boolean extractAddend()
      Determine if addend data must be extracted
      Returns:
      true if relocation does not provide addend data and it must be extracted from relocation target if appropriate

    • getProgram

      public final Program getProgram()

    • isBigEndian

      public final boolean isBigEndian()

    • getElfHeader

      public final ElfHeader getElfHeader()

    • getLoadHelper

      public final ElfLoadHelper getLoadHelper()

    • getLoadAdapter

      public final ElfLoadAdapter getLoadAdapter()

    • getLog

      public final MessageLog getLog()

    • getSymbol

      public final ElfSymbol getSymbol(int symbolIndex)
      Get the Elf symbol which corresponds to the specified index. Each relocation table may correspond to a specific symbol table to which the specified symbolIndex will be applied. In the absense of a corresponding symbol table index 0 will return a special null symbol.
      Parameters:
      symbolIndex - symbol index
      Returns:
      Elf symbol which corresponds to symbol index or null if out of range

    • getSymbolName

      public final String getSymbolName(int symbolIndex)
      Get the ELF symbol name which corresponds to the specified index.
      Parameters:
      symbolIndex - symbol index
      Returns:
      symbol name which corresponds to symbol index or null if out of range

    • getSymbolAddress

      public Address getSymbolAddress(ElfSymbol symbol)
      Get the program address at which the specified Elf symbol was placed.
      Parameters:
      symbol - Elf symbol
      Returns:
      program address

    • getSymbolValue

      public long getSymbolValue(ElfSymbol symbol)
      Get the adjusted symbol value based upon its placement within the program. This value may differ from symbol.getValue() and will reflect the addressable unit/word offset of it program address.
      Parameters:
      symbol - Elf symbol
      Returns:
      adjusted Elf symbol value or 0 if symbol mapping not found

    • getGOTValue

      public long getGOTValue() throws NotFoundException
      Returns the appropriate .got section using the DT_PLTGOT value defined in the .dynamic section. If no such dynamic value defined, the symbol offset for _GLOBAL_OFFSET_TABLE_ will be used, otherwise a NotFoundException will be thrown.
      Returns:
      the .got section address offset
      Throws:
      NotFoundException - if the dynamic DT_PLTGOT not defined and _GLOBAL_OFFSET_TABLE_ symbol not defined

    • dispose

      public void dispose()
      Dispose relocation context when processing of corresponding relocation table is complete. Instance should be disposed to allow all program changes to be flushed prior to processing a subsequent relocation table.

    • getRelocationAddress

      public Address getRelocationAddress(Address baseAddress, long relocOffset)
      Get relocation address
      Parameters:
      baseAddress - base address
      relocOffset - relocation offset relative to baseAddress
      Returns:
      relocation address