Skip to content

Added support for symbol relocation for RISC-V architecture #613

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 12 commits into
base: main
Choose a base branch
from
Open

Added support for symbol relocation for RISC-V architecture #613

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
12 commits
Select commit Hold shift + click to select a range
bf838d2
Added support for RISC-V symbol relocation
adjordjevic-TT Apr 1, 2025
38dd7e5
Added source link for reloc table
adjordjevic-TT Apr 2, 2025
65d3518
Changed 6 bit reloc functions
adjordjevic-TT Apr 2, 2025
f575e3f
Revert "Added source link for reloc table"
adjordjevic-TT Apr 2, 2025
ec137d3
Revert "Changed 6 bit reloc functions"
adjordjevic-TT Apr 2, 2025
6b4ea2a
Revert "Revert "Added source link for reloc table""
adjordjevic-TT Apr 2, 2025
52a932c
Python version
adjordjevic-TT Apr 9, 2025
be35049
Revert name change
adjordjevic-TT Apr 9, 2025
2512c30
Added set8 reloc type
adjordjevic-TT Apr 9, 2025
6950a75
Added sub8 reloc type
adjordjevic-TT Apr 9, 2025
1fa86fe
Added more reloc types
adjordjevic-TT Apr 9, 2025
11bb931
Reverted py version to 3.9
adjordjevic-TT Apr 9, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
62 changes: 62 additions & 0 deletions elftools/elf/enums.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -788,6 +788,68 @@
_default_=Pass,
)

# https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-elf.adoc#reloc-table
ENUM_RELOC_TYPE_RISCV = dict(
R_RISCV_NONE = 0,
R_RISCV_32 = 1,
R_RISCV_64 = 2,
R_RISCV_RELATIVE = 3,
R_RISCV_COPY = 4,
R_RISCV_JUMP_SLOT = 5,
R_RISCV_TLS_DTPMOD32 = 6,
R_RISCV_TLS_DTPMOD64 = 7,
R_RISCV_TLS_DTPREL32 = 8,
R_RISCV_TLS_DTPREL64 = 9,
R_RISCV_TLS_TPREL32 = 10,
R_RISCV_TLS_TPREL64 = 11,
R_RISCV_TLSDESC = 12,
R_RISCV_BRANCH = 16,
R_RISCV_JAL = 17,
R_RISCV_CALL = 18,
R_RISCV_CALL_PLT = 19,
R_RISCV_GOT_HI20 = 20,
R_RISCV_TLS_GOT_HI20 = 21,
R_RISCV_TLS_GD_HI20 = 22,
R_RISCV_PCREL_HI20 = 23,
R_RISCV_PCREL_LO12_I = 24,
R_RISCV_PCREL_LO12_S = 25,
R_RISCV_HI20 = 26,
R_RISCV_LO12_I = 27,
R_RISCV_LO12_S = 28,
R_RISCV_TPREL_HI20 = 29,
R_RISCV_TPREL_LO12_I = 30,
R_RISCV_TPREL_LO12_S = 31,
R_RISCV_TPREL_ADD = 32,
R_RISCV_ADD8 = 33,
R_RISCV_ADD16 = 34,
R_RISCV_ADD32 = 35,
R_RISCV_ADD64 = 36,
R_RISCV_SUB8 = 37,
R_RISCV_SUB16 = 38,
R_RISCV_SUB32 = 39,
R_RISCV_SUB64 = 40,
R_RISCV_GOT32_PCREL = 41,
R_RISCV_ALIGN = 43,
R_RISCV_RVC_BRANCH = 44,
R_RISCV_RVC_JUMP = 45,
R_RISCV_RELAX = 51,
R_RISCV_SUB6 = 52,
R_RISCV_SET6 = 53,
R_RISCV_SET8 = 54,
R_RISCV_SET16 = 55,
R_RISCV_SET32 = 56,
R_RISCV_32_PCREL = 57,
R_RISCV_IRELATIVE = 58,
R_RISCV_PLT32 = 59,
R_RISCV_SET_ULEB128 = 60,
R_RISCV_SUB_ULEB128 = 61,
R_RISCV_TLSDESC_HI20 = 62,
R_RISCV_TLSDESC_LOAD_LO12 = 63,
R_RISCV_TLSDESC_ADD_LO12 = 64,
R_RISCV_TLSDESC_CALL = 65,
_default_=Pass,
)

ENUM_RELOC_TYPE_x64 = dict(
R_X86_64_NONE=0,
R_X86_64_64=1,
Expand Down
47 changes: 46 additions & 1 deletion elftools/elf/relocation.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,7 @@
from ..common.utils import elf_assert, struct_parse
from .sections import Section
from .enums import (
ENUM_RELOC_TYPE_i386, ENUM_RELOC_TYPE_x64, ENUM_RELOC_TYPE_MIPS,
ENUM_RELOC_TYPE_RISCV, ENUM_RELOC_TYPE_i386, ENUM_RELOC_TYPE_x64, ENUM_RELOC_TYPE_MIPS,
ENUM_RELOC_TYPE_ARM, ENUM_RELOC_TYPE_AARCH64, ENUM_RELOC_TYPE_PPC64,
ENUM_RELOC_TYPE_S390X, ENUM_RELOC_TYPE_BPF, ENUM_RELOC_TYPE_LOONGARCH)
from ..construct import Container
Expand Down Expand Up @@ -234,6 +234,12 @@ def _arm_reloc_calc_sym_plus_value_pcrel(value, sym_value, offset, addend=0):
def _bpf_64_32_reloc_calc_sym_plus_addend(value, sym_value, offset, addend=0):
return (sym_value + addend) // 8 - 1

def _reloc_calc_value_plus_sym_6(value, sym_value, offset, addend=0):
return ((sym_value + addend) & 0x3F) | (value & 0xC0)

def _reloc_calc_value_minus_sym_addend_6(value, sym_value, offset, addend=0):
return (((value & 0x3F) - sym_value - addend) & 0x3F) | (value & 0xC0)


class RelocationHandler:
""" Handles the logic of relocations in ELF files.
Expand Down Expand Up @@ -319,6 +325,8 @@ def _do_apply_relocation(self, stream, reloc, symtab):
raise ELFRelocationError(
'Unexpected REL relocation for LoongArch: %s' % reloc)
recipe = self._RELOCATION_RECIPES_LOONGARCH.get(reloc_type, None)
elif self.elffile.get_machine_arch() == 'RISC-V':
recipe = self._RELOCATION_RECIPES_RISCV.get(reloc_type, None)

if recipe is None:
raise ELFRelocationError(
Expand Down Expand Up @@ -509,5 +517,42 @@ def _do_apply_relocation(self, stream, reloc, symtab):
ENUM_RELOC_TYPE_S390X['R_390_64']: _RELOCATION_RECIPE_TYPE(
bytesize=8, has_addend=True, calc_func=_reloc_calc_sym_plus_addend),
}

# https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-elf.adoc#reloc-table
_RELOCATION_RECIPES_RISCV = {
ENUM_RELOC_TYPE_RISCV['R_RISCV_NONE']: _RELOCATION_RECIPE_TYPE(
bytesize=8, has_addend=False, calc_func=_reloc_calc_identity),
ENUM_RELOC_TYPE_RISCV['R_RISCV_32']: _RELOCATION_RECIPE_TYPE(
bytesize=4, has_addend=True, calc_func=_reloc_calc_sym_plus_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_64']: _RELOCATION_RECIPE_TYPE(
bytesize=8, has_addend=True, calc_func=_reloc_calc_sym_plus_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_ADD8']: _RELOCATION_RECIPE_TYPE(
bytesize=1, has_addend=True, calc_func=_reloc_calc_sym_plus_value),
ENUM_RELOC_TYPE_RISCV['R_RISCV_ADD16']: _RELOCATION_RECIPE_TYPE(
bytesize=2, has_addend=True, calc_func=_reloc_calc_sym_plus_value),
ENUM_RELOC_TYPE_RISCV['R_RISCV_ADD32']: _RELOCATION_RECIPE_TYPE(
bytesize=4, has_addend=True, calc_func=_reloc_calc_sym_plus_value),
ENUM_RELOC_TYPE_RISCV['R_RISCV_ADD64']: _RELOCATION_RECIPE_TYPE(
bytesize=8, has_addend=True, calc_func=_reloc_calc_sym_plus_value),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SUB8']: _RELOCATION_RECIPE_TYPE(
bytesize=1, has_addend=True, calc_func=_reloc_calc_value_minus_sym_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SUB16']: _RELOCATION_RECIPE_TYPE(
bytesize=2, has_addend=True, calc_func=_reloc_calc_value_minus_sym_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SUB32']: _RELOCATION_RECIPE_TYPE(
bytesize=4, has_addend=True, calc_func=_reloc_calc_value_minus_sym_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SUB64']: _RELOCATION_RECIPE_TYPE(
bytesize=8, has_addend=True, calc_func=_reloc_calc_value_minus_sym_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SUB6']: _RELOCATION_RECIPE_TYPE(
bytesize=1, has_addend=True, calc_func=_reloc_calc_value_minus_sym_addend_6),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SET6']: _RELOCATION_RECIPE_TYPE(
bytesize=1, has_addend=True, calc_func=_reloc_calc_value_plus_sym_6),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SET8']: _RELOCATION_RECIPE_TYPE(
bytesize=1, has_addend=True, calc_func=_reloc_calc_sym_plus_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SET16']: _RELOCATION_RECIPE_TYPE(
bytesize=2, has_addend=True, calc_func=_reloc_calc_sym_plus_addend),
ENUM_RELOC_TYPE_RISCV['R_RISCV_SET32']: _RELOCATION_RECIPE_TYPE(
bytesize=4, has_addend=True, calc_func=_reloc_calc_sym_plus_addend),
}