# Copyright 2017 Reswitched Team
#
# Permission to use, copy, modify, and/or distribute this software for any purpose with or
# without fee is hereby granted, provided that the above copyright notice and this permission
# notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
# SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
# THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY
# DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
# CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE
# OR PERFORMANCE OF THIS SOFTWARE.
# nxo64.py: IDA loader and library for reading nso/nro files
import gzip, math, os, re, struct, sys
from io import BytesIO
from cStringIO import StringIO
import lz4.block
uncompress = lz4.block.decompress
def get_file_size(f):
filesize = 0
try:
filesize = f.size()
except:
ptell = f.tell()
f.seek(0, 2)
filesize = f.tell()
f.seek(ptell)
return filesize
class BinFile(object):
def __init__(self, li):
self._f = li
def read(self, arg):
if isinstance(arg, str):
fmt = '<' + arg
size = struct.calcsize(fmt)
raw = self._f.read(size)
out = struct.unpack(fmt, raw)
if len(out) == 1:
return out[0]
return out
elif arg is None:
return self.read_to_end()
else:
out = self._f.read(arg)
if isinstance(arg, (int,long)) and len(out) != arg:
pass #print 'warning: read of %d bytes got %d bytes' % (arg, len(out))
return out
def read_to_end(self):
return self.read(self.size()-self.tell())
def size(self):
return get_file_size(self._f)
def read_from(self, arg, offset):
old = self.tell()
try:
self.seek(offset)
out = self.read(arg)
finally:
self.seek(old)
return out
def seek(self, off):
self._f.seek(off)
def skip(self, dist):
self.seek(self.tell()+dist)
def close(self):
self._f.close()
def tell(self):
return self._f.tell()
(DT_NULL, DT_NEEDED, DT_PLTRELSZ, DT_PLTGOT, DT_HASH, DT_STRTAB, DT_SYMTAB, DT_RELA, DT_RELASZ,
DT_RELAENT, DT_STRSZ, DT_SYMENT, DT_INIT, DT_FINI, DT_SONAME, DT_RPATH, DT_SYMBOLIC, DT_REL,
DT_RELSZ, DT_RELENT, DT_PLTREL, DT_DEBUG, DT_TEXTREL, DT_JMPREL, DT_BIND_NOW, DT_INIT_ARRAY,
DT_FINI_ARRAY, DT_INIT_ARRAYSZ, DT_FINI_ARRAYSZ, DT_RUNPATH, DT_FLAGS) = xrange(31)
DT_RELRSZ, DT_RELR, DT_RELRENT = 0x23, 0x24, 0x25
DT_GNU_HASH = 0x6ffffef5
DT_VERSYM = 0x6ffffff0
DT_RELACOUNT = 0x6ffffff9
DT_RELCOUNT = 0x6ffffffa
DT_FLAGS_1 = 0x6ffffffb
DT_VERDEF = 0x6ffffffc
DT_VERDEFNUM = 0x6ffffffd
STT_NOTYPE = 0
STT_OBJECT = 1
STT_FUNC = 2
STT_SECTION = 3
STB_LOCAL = 0
STB_GLOBAL = 1
STB_WEAK = 2
R_ARM_ABS32 = 2
R_ARM_TLS_DESC = 13
R_ARM_GLOB_DAT = 21
R_ARM_JUMP_SLOT = 22
R_ARM_RELATIVE = 23
R_FAKE_RELR = -1
R_AARCH64_ABS64 = 257
R_AARCH64_GLOB_DAT = 1025
R_AARCH64_JUMP_SLOT = 1026
R_AARCH64_RELATIVE = 1027
R_AARCH64_TLSDESC = 1031
MULTIPLE_DTS = set([DT_NEEDED])
class Range(object):
def __init__(self, start, size):
self.start = start
self.size = size
self.end = start+size
self._inclend = start+size-1
def overlaps(self, other):
return self.start <= other._inclend and other.start <= self._inclend
def includes(self, other):
return other.start >= self.start and other._inclend <= self._inclend
def __repr__(self):
return 'Range(0x%X -> 0x%X)' % (self.start, self.end)
class Segment(object):
def __init__(self, r, name, kind):
self.range = r
self.name = name
self.kind = kind
self.sections = []
def add_section(self, s):
for i in self.sections:
assert not i.range.overlaps(s.range), '%r overlaps %r' % (s, i)
self.sections.append(s)
class Section(object):
def __init__(self, r, name):
self.range = r
self.name = name
def __repr__(self):
return 'Section(%r, %r)' % (self.range, self.name)
def suffixed_name(name, suffix):
if suffix == 0:
return name
return '%s.%d' % (name, suffix)
class SegmentBuilder(object):
def __init__(self):
self.segments = []
self._sections = []
def add_segment(self, start, size, name, kind):
r = Range(start, size)
for i in self.segments:
assert not r.overlaps(i.range)
self.segments.append(Segment(r, name, kind))
def add_section(self, name, start, end=None, size=None):
assert end is None or size is None
if size is None:
size = end-start
if size > 0:
#assert size > 0
r = Range(start, size)
self._sections.append((r, name))
def _add_sections_to_segments(self):
for r, name in self._sections:
for i in self.segments:
if i.range.includes(r):
i.add_section(Section(r, name))
break
else:
assert False, 'no containing segment for %r' % (name,)
def flatten(self):
self._add_sections_to_segments()
self.segments.sort(key=lambda s: s.range.start)
parts = []
for segment in self.segments:
suffix = 0
segment.sections.sort(key=lambda s: s.range.start)
pos = segment.range.start
for section in segment.sections:
if pos < section.range.start:
parts.append((pos, section.range.start, suffixed_name(segment.name, suffix), segment.kind))
suffix += 1
pos = section.range.start
parts.append((section.range.start, section.range.end, section.name, segment.kind))
pos = section.range.end
if pos < segment.range.end:
parts.append((pos, segment.range.end, suffixed_name(segment.name, suffix), segment.kind))
suffix += 1
pos = segment.range.end
return parts
class ElfSym(object):
def __init__(self, name, info, other, shndx, value, size):
self.name = name
self.shndx = shndx
self.value = value
self.size = size
self.vis = other & 3
self.type = info & 0xF
self.bind = info >> 4
def __repr__(self):
return 'Sym(name=%r, shndx=0x%X, value=0x%X, size=0x%X, vis=%r, type=%r, bind=%r)' % (
self.name, self.shndx, self.value, self.size, self.vis, self.type, self.bind)
class NxoFileBase(object):
def __init__(self, f, segment_data=None):
self.binfile = f
# read MOD
self.modoff = f.read_from('I', 4)
f.seek(self.modoff)
if f.read('4s') != 'MOD0':
raise NxoException('invalid MOD0 magic')
self.dynamicoff = self.modoff + f.read('i')
self.bssoff = self.modoff + f.read('i')
self.bssend = self.modoff + f.read('i')
self.unwindoff = self.modoff + f.read('i')
self.unwindend = self.modoff + f.read('i')
self.moduleoff = self.modoff + f.read('i')
builder = SegmentBuilder()
# read dynamic
self.armv7 = (f.read_from('Q', self.dynamicoff) > 0xFFFFFFFF or f.read_from('Q', self.dynamicoff+0x10) > 0xFFFFFFFF)
self.offsize = 4 if self.armv7 else 8
f.seek(self.dynamicoff)
self.dynamic = dynamic = {}
for i in MULTIPLE_DTS:
dynamic[i] = []
for i in xrange((f.size() - self.dynamicoff) / 0x10):
tag, val = f.read('II' if self.armv7 else 'QQ')
if tag == DT_NULL:
break
if tag in MULTIPLE_DTS:
dynamic[tag].append(val)
else:
dynamic[tag] = val
self.dynamicsize = f.tell() - self.dynamicoff
builder.add_section('.dynamic', self.dynamicoff, end=self.dynamicoff + self.dynamicsize)
builder.add_section('.eh_frame_hdr', self.unwindoff, end=self.unwindend)
# read .dynstr
if DT_STRTAB in dynamic and DT_STRSZ in dynamic:
f.seek(dynamic[DT_STRTAB])
self.dynstr = f.read(dynamic[DT_STRSZ])
else:
self.dynstr = '\0'
print 'warning: no dynstr'
for startkey, szkey, name in [
(DT_STRTAB, DT_STRSZ, '.dynstr'),
(DT_INIT_ARRAY, DT_INIT_ARRAYSZ, '.init_array'),
(DT_FINI_ARRAY, DT_FINI_ARRAYSZ, '.fini_array'),
(DT_RELA, DT_RELASZ, '.rela.dyn'),
(DT_REL, DT_RELSZ, '.rel.dyn'),
(DT_RELR, DT_RELRSZ, '.relr.dyn'),
(DT_JMPREL, DT_PLTRELSZ, ('.rel.plt' if self.armv7 else '.rela.plt')),
]:
if startkey in dynamic and szkey in dynamic:
builder.add_section(name, dynamic[startkey], size=dynamic[szkey])
# TODO
#build_id = content.find('\x04\x00\x00\x00\x14\x00\x00\x00\x03\x00\x00\x00GNU\x00')
#if build_id >= 0:
# builder.add_section('.note.gnu.build-id', build_id, size=0x24)
#else:
# build_id = content.index('\x04\x00\x00\x00\x10\x00\x00\x00\x03\x00\x00\x00GNU\x00')
# if build_id >= 0:
# builder.add_section('.note.gnu.build-id', build_id, size=0x20)
if DT_HASH in dynamic:
hash_start = dynamic[DT_HASH]
f.seek(hash_start)
nbucket, nchain = f.read('II')
f.skip(nbucket * 4)
f.skip(nchain * 4)
hash_end = f.tell()
builder.add_section('.hash', hash_start, end=hash_end)
if DT_GNU_HASH in dynamic:
gnuhash_start = dynamic[DT_GNU_HASH]
f.seek(gnuhash_start)
nbuckets, symoffset, bloom_size, bloom_shift = f.read('IIII')
f.skip(bloom_size * self.offsize)
buckets = [f.read('I') for i in range(nbuckets)]
max_symix = max(buckets) if buckets else 0
if max_symix >= symoffset:
f.skip((max_symix - symoffset) * 4)
while (f.read('I') & 1) == 0:
pass
gnuhash_end = f.tell()
builder.add_section('.gnu.hash', gnuhash_start, end=gnuhash_end)
self.needed = [self.get_dynstr(i) for i in self.dynamic[DT_NEEDED]]
# load .dynsym
self.symbols = symbols = []
f.seek(dynamic[DT_SYMTAB])
while True:
if dynamic[DT_SYMTAB] < dynamic[DT_STRTAB] and f.tell() >= dynamic[DT_STRTAB]:
break
if self.armv7:
st_name, st_value, st_size, st_info, st_other, st_shndx = f.read('IIIBBH')
else:
st_name, st_info, st_other, st_shndx, st_value, st_size = f.read('IBBHQQ')
if st_name > len(self.dynstr):
break
symbols.append(ElfSym(self.get_dynstr(st_name), st_info, st_other, st_shndx, st_value, st_size))
builder.add_section('.dynsym', dynamic[DT_SYMTAB], end=f.tell())
self.plt_entries = []
self.relocations = []
locations = set()
if DT_REL in dynamic:
locations |= self.process_relocations(f, symbols, dynamic[DT_REL], dynamic[DT_RELSZ])
if DT_RELA in dynamic:
locations |= self.process_relocations(f, symbols, dynamic[DT_RELA], dynamic[DT_RELASZ])
if DT_RELR in dynamic:
locations |= self.process_relocations_relr(f, dynamic[DT_RELR], dynamic[DT_RELRSZ])
if segment_data is None:
# infer segment info
rloc_guess = (dynamic[DT_REL if DT_REL in dynamic else DT_RELA] & ~0xFFF)
dloc_guess = (min(i for i in locations if i != 0) & ~0xFFF)
dloc_guess2 = None
modoff = f.read_from('I', 4)
if self.modoff != 8:
search_start = (self.modoff + 0xFFF) & ~0xFFF
for i in range(search_start, f.size(), 0x1000):
count = 0
for j in range(4, 0x1000, 4):
if f.read_from('I', i - j) != 0:
break
count += 1
if count > 6:
dloc_guess2 = i
break
if dloc_guess2 is not None and dloc_guess2 < dloc_guess:
dloc_guess = dloc_guess2
if segment_data:
tloc, tsize, rloc, rsize, dloc, dsize = segment_data
assert rloc_guess == rloc
assert dloc_guess == dloc
self.textoff = 0
self.textsize = rloc_guess
self.rodataoff = rloc_guess
self.rodatasize = dloc_guess - rloc_guess
self.dataoff = dloc_guess
else:
tloc, tsize, rloc, rsize, dloc, dsize = segment_data
self.textoff = tloc
self.textsize = tsize
self.rodataoff = rloc
self.rodatasize = rsize
self.dataoff = dloc
self.datasize = self.bssoff - self.dataoff
self.bsssize = self.bssend - self.bssoff
plt_got_end = None
if DT_JMPREL in dynamic:
pltlocations = self.process_relocations(f, symbols, dynamic[DT_JMPREL], dynamic[DT_PLTRELSZ])
locations |= pltlocations
plt_got_start = min(pltlocations)
plt_got_end = max(pltlocations) + self.offsize
if DT_PLTGOT in dynamic:
builder.add_section('.got.plt', dynamic[DT_PLTGOT], end=plt_got_end)
if not self.armv7:
f.seek(0)
text = f.read(self.textsize)
last = 12
while True:
pos = text.find(struct.pack('<I', 0xD61F0220), last)
if pos == -1: break
last = pos+1
if (pos % 4) != 0: continue
off = pos - 12
a, b, c, d = struct.unpack_from('<IIII', text, off)
if d == 0xD61F0220 and (a & 0x9f00001f) == 0x90000010 and (b & 0xffe003ff) == 0xf9400211:
base = off & ~0xFFF
immhi = (a >> 5) & 0x7ffff
immlo = (a >> 29) & 3
paddr = base + ((immlo << 12) | (immhi << 14))
poff = ((b >> 10) & 0xfff) << 3
target = paddr + poff
if plt_got_start <= target < plt_got_end:
self.plt_entries.append((off, target))
if len(self.plt_entries) > 0:
builder.add_section('.plt', min(self.plt_entries)[0], end=max(self.plt_entries)[0] + 0x10)
# try to find the ".got" which should follow the ".got.plt"
good = False
got_start = (plt_got_end if plt_got_end is not None else self.dynamicoff + self.dynamicsize)
got_end = self.offsize + got_start
while (got_end in locations or (plt_got_end is None and got_end < dynamic[DT_INIT_ARRAY])) and (DT_INIT_ARRAY not in dynamic or got_end < dynamic[DT_INIT_ARRAY] or dynamic[DT_INIT_ARRAY] < got_start):
good = True
got_end += self.offsize
#print 'got_start got_end %X %X %s %X' % (got_start, got_end, str(got_end in locations), dynamic[DT_INIT_ARRAY])
if good:
self.got_start = got_start
self.got_end = got_end
builder.add_section('.got', self.got_start, end=self.got_end)
self.eh_table = []
if not self.armv7:
f.seek(self.unwindoff)
version, eh_frame_ptr_enc, fde_count_enc, table_enc = f.read('BBBB')
if not any(i == 0xff for i in (eh_frame_ptr_enc, fde_count_enc, table_enc)): # DW_EH_PE_omit
#assert eh_frame_ptr_enc == 0x1B # DW_EH_PE_pcrel | DW_EH_PE_sdata4
#assert fde_count_enc == 0x03 # DW_EH_PE_absptr | DW_EH_PE_udata4
#assert table_enc == 0x3B # DW_EH_PE_datarel | DW_EH_PE_sdata4
if eh_frame_ptr_enc == 0x1B and fde_count_enc == 0x03 and table_enc == 0x3B:
base_offset = f.tell()
eh_frame = base_offset + f.read('i')
fde_count = f.read('I')
#assert 8 * fde_count == self.unwindend - f.tell()
if 8 * fde_count == self.unwindend - f.tell():
for i in range(fde_count):
pc = self.unwindoff + f.read('i')
entry = self.unwindoff + f.read('i')
self.eh_table.append((pc, entry))
# TODO: we miss the last one, but better than nothing
last_entry = sorted(self.eh_table, key=lambda x: x[1])[-1][1]
builder.add_section('.eh_frame', eh_frame, end=last_entry)
for off,sz,name,kind in [
(self.textoff, self.textsize, '.text', 'CODE'),
(self.rodataoff, self.rodatasize, '.rodata', 'CONST'),
(self.dataoff, self.datasize, '.data', 'DATA'),
(self.bssoff, self.bsssize, '.bss', 'BSS'),
]:
builder.add_segment(off, sz, name, kind)
self.sections = []
for start, end, name, kind in builder.flatten():
self.sections.append((start, end, name, kind))
self._addr_to_name = None
self._plt_lookup = None
@property
def addr_to_name(self):
if self._addr_to_name is None:
d = {}
for sym in self.symbols:
if sym.shndx:
d[sym.value] = sym.name
self._addr_to_name = d
return self._addr_to_name
@property
def plt_lookup(self):
if self._plt_lookup is None:
# generate lookups for .plt call redirection
got_value_lookup = {}
for offset, r_type, sym, addend in self.relocations:
if r_type in (R_AARCH64_GLOB_DAT, R_AARCH64_JUMP_SLOT, R_AARCH64_ABS64) and addend == 0 and sym.shndx:
got_value_lookup[offset] = sym.value
self._plt_lookup = {}
for func, target in self.plt_entries:
if target in got_value_lookup:
self._plt_lookup[func] = got_value_lookup[target]
return self._plt_lookup
def process_relocations(self, f, symbols, offset, size):
locations = set()
f.seek(offset)
relocsize = 8 if self.armv7 else 0x18
for i in xrange(size / relocsize):
# NOTE: currently assumes all armv7 relocs have no addends,
# and all 64-bit ones do.
if self.armv7:
offset, info = f.read('II')
addend = None
r_type = info & 0xff
r_sym = info >> 8
else:
offset, info, addend = f.read('QQq')
r_type = info & 0xffffffff
r_sym = info >> 32
sym = symbols[r_sym] if r_sym != 0 else None
if r_type != R_AARCH64_TLSDESC and r_type != R_ARM_TLS_DESC:
locations.add(offset)
self.relocations.append((offset, r_type, sym, addend))
return locations
def process_relocations_relr(self, f, offset, size):
locations = set()
f.seek(offset)
relocsize = 8
for i in xrange(size / relocsize):
entry = f.read('Q')
if entry & 1:
entry >>= 1
i = 0
while i < (relocsize * 8) - 1:
if entry & (1 << i):
locations.add(where + i * relocsize)
self.relocations.append((where + i * relocsize, R_FAKE_RELR, None, 0))
i += 1
where += relocsize * ((relocsize * 8) - 1)
else:
# Where
where = entry
locations.add(where)
self.relocations.append((where, R_FAKE_RELR, None, 0))
where += relocsize
return locations
def get_dynstr(self, o):
return self.dynstr[o:self.dynstr.index('\0', o)]
def get_path_or_name(self):
path = None
for off, end, name, class_ in self.sections:
if name == '.rodata' and end-off < 0x1000 and end-off > 8:
id_ = self.binfile.read_from(end-off, off)
length = struct.unpack_from('<I', id_, 4)[0]
if length + 8 <= len(id_):
id_ = id_[8:length + 8]
return id_
self.binfile.seek(self.rodataoff)
as_string = self.binfile.read(self.rodatasize)
if path is None:
strs = re.findall(r'[a-z]:[\\/][ -~]{5,}\.n[rs]s', as_string, flags=re.IGNORECASE)
if strs:
return strs[-1]
return None
def get_name(self):
name = self.get_path_or_name()
if name is not None:
name = name.split('/')[-1].split('\\')[-1]
if name.lower().endswith(('.nss', '.nrs')):
name = name[:-4]
return name
class NsoFile(NxoFileBase):
def __init__(self, fileobj):
f = BinFile(fileobj)
if f.read_from('4s', 0) != 'NSO0':
raise NxoException('Invalid NSO magic')
flags = f.read_from('I', 0xC)
toff, tloc, tsize = f.read_from('III', 0x10)
roff, rloc, rsize = f.read_from('III', 0x20)
doff, dloc, dsize = f.read_from('III', 0x30)
tfilesize, rfilesize, dfilesize = f.read_from('III', 0x60)
bsssize = f.read_from('I', 0x3C)
text = uncompress(f.read_from(tfilesize, toff), uncompressed_size=tsize) if flags & 1 else f.read_from(tfilesize, toff)
ro = uncompress(f.read_from(rfilesize, roff), uncompressed_size=rsize) if flags & 2 else f.read_from(rfilesize, roff)
data = uncompress(f.read_from(dfilesize, doff), uncompressed_size=dsize) if flags & 4 else f.read_from(dfilesize, doff)
full = text
if rloc >= len(full):
full += '\0' * (rloc - len(full))
else:
print 'truncating?'
full = full[:rloc]
full += ro
if dloc >= len(full):
full += '\0' * (dloc - len(full))
else:
print 'truncating?'
full = full[:dloc]
full += data
self.full = full
super(NsoFile, self).__init__(BinFile(StringIO(full)), (tloc, tsize, rloc, rsize, dloc, dsize))
class NroFile(NxoFileBase):
def __init__(self, fileobj):
f = BinFile(fileobj)
if f.read_from('4s', 0x10) != 'NRO0':
raise NxoException('Invalid NRO magic')
f.seek(0x20)
tloc, tsize = f.read('II')
rloc, rsize = f.read('II')
dloc, dsize = f.read('II')
# copy f, since all other formats allow the original file to be closed
f.seek(0)
full = f.read(f.size())
filecopy = BinFile(StringIO(full))
super(NroFile, self).__init__(filecopy, (tloc, tsize, rloc, rsize, dloc, dsize))
def kip1_blz_decompress(compressed):
compressed_size, init_index, uncompressed_addl_size = struct.unpack('<III', compressed[-0xC:])
decompressed = compressed[:] + '\x00' * uncompressed_addl_size
decompressed_size = len(decompressed)
if not (compressed_size + uncompressed_addl_size):
return ''
decompressed = map(ord, decompressed)
cmp_start = len(compressed) - compressed_size
cmp_ofs = compressed_size - init_index
out_ofs = compressed_size + uncompressed_addl_size
while out_ofs > 0:
cmp_ofs -= 1
control = decompressed[cmp_start + cmp_ofs]
for i in xrange(8):
if control & 0x80:
if cmp_ofs < 2 - cmp_start:
raise ValueError('Compression out of bounds!')
cmp_ofs -= 2
segmentoffset = decompressed[cmp_start + cmp_ofs] | (decompressed[cmp_start + cmp_ofs + 1] << 8)
segmentsize = ((segmentoffset >> 12) & 0xF) + 3
segmentoffset &= 0x0FFF
segmentoffset += 2
if out_ofs < segmentsize - cmp_start:
raise ValueError('Compression out of bounds!')
for j in xrange(segmentsize):
if out_ofs + segmentoffset >= decompressed_size:
raise ValueError('Compression out of bounds!')
data = decompressed[cmp_start + out_ofs + segmentoffset]
out_ofs -= 1
decompressed[cmp_start + out_ofs] = data
else:
if out_ofs < 1 - cmp_start:
raise ValueError('Compression out of bounds!')
out_ofs -= 1
cmp_ofs -= 1
decompressed[cmp_start + out_ofs] = decompressed[cmp_start + cmp_ofs]
control <<= 1
control &= 0xFF
if not out_ofs:
break
return ''.join(map(chr, decompressed))
class KipFile(NxoFileBase):
def __init__(self, fileobj):
f = BinFile(fileobj)
if f.read_from('4s', 0) != 'KIP1':
raise NxoException('Invalid KIP magic')
flags = f.read_from('b', 0x1F)
tloc, tsize, tfilesize = f.read_from('III', 0x20)
rloc, rsize, rfilesize = f.read_from('III', 0x30)
dloc, dsize, dfilesize = f.read_from('III', 0x40)
toff = 0x100
roff = toff + tfilesize
doff = roff + rfilesize
bsssize = f.read_from('I', 0x18)
text = kip1_blz_decompress(str(f.read_from(tfilesize, toff))) if flags & 1 else f.read_from(tfilesize, toff)
ro = kip1_blz_decompress(str(f.read_from(rfilesize, roff))) if flags & 2 else f.read_from(rfilesize, roff)
data = kip1_blz_decompress(str(f.read_from(dfilesize, doff))) if flags & 4 else f.read_from(dfilesize, doff)
full = text
if rloc >= len(full):
full += '\0' * (rloc - len(full))
else:
print 'truncating?'
full = full[:rloc]
full += ro
if dloc >= len(full):
full += '\0' * (dloc - len(full))
else:
print 'truncating?'
full = full[:dloc]
full += data
super(KipFile, self).__init__(BinFile(StringIO(full)), (tloc, tsize, rloc, rsize, dloc, dsize))
class MemoryDumpFile(NxoFileBase):
def __init__(self, fileobj):
f = BinFile(fileobj)
if f.read_from('4s', f.read_from('I', 4)) != 'MOD0':
raise NxoException('Invalid MOD0 magic')
f.seek(0)
full = f.read(f.size())
filecopy = BinFile(StringIO(full))
super(MemoryDumpFile, self).__init__(filecopy)
class NxoException(Exception):
pass
def looks_like_memory_dump(fileobj):
fileobj.seek(0)
header = fileobj.read(8)
if len(header) < 8:
return False
modoff = struct.unpack_from('<I', header, 4)[0]
if modoff + 0x1c < get_file_size(fileobj):
fileobj.seek(modoff)
if fileobj.read(4) == 'MOD0':
return True
return False
def load_nxo(fileobj):
fileobj.seek(0)
header = fileobj.read(0x14)
if header[:4] == 'NSO0':
return NsoFile(fileobj)
elif header[:4] == 'KIP1':
return KipFile(fileobj)
elif header[0x10:0x14] == 'NRO0':
return NroFile(fileobj)
elif looks_like_memory_dump(fileobj):
return MemoryDumpFile(fileobj)
raise NxoException('not an NRO or NSO file')
try:
import idaapi
import idc
except ImportError:
pass
else:
# IDA specific code
NRO_FORMAT = 'Switch binary (NRO)'
NSO_FORMAT = 'Switch binary (NSO)'
KIP_FORMAT = 'Switch binary (KIP)'
RAW_FORMAT = 'Switch raw binary memory dump'
SDK_FORMAT = 'Switch SDK binary (NSO, with arm64 .plt call rewriting hack)'
RAW_SDK_FORMAT = 'Switch SDK (raw memory dump, with arm64 .plt call rewriting hack)'
EXEFS_FORMAT = 'Switch exefs (multiple files, for use with Mephisto)'
EXEFS_LOW_FORMAT = 'Switch exefs with 31-bit addressing (multiple files, for use with Mephisto)'
OPT_BYPASS_PLT = 'BYPASS_PLT'
OPT_EXEFS_LOAD = 'EXEFS_LOAD'
OPT_LOAD_31_BIT = 'LOAD_31_BIT'
FORMAT_OPTIONS = {
NRO_FORMAT: [],
NSO_FORMAT: [],
KIP_FORMAT: [],
RAW_FORMAT: [],
SDK_FORMAT: [OPT_BYPASS_PLT],
RAW_SDK_FORMAT: [OPT_BYPASS_PLT],
EXEFS_FORMAT: [OPT_EXEFS_LOAD],
EXEFS_LOW_FORMAT: [OPT_EXEFS_LOAD, OPT_LOAD_31_BIT],
}
PRIMARY_EXEFS_NAMES = ['main', 'rtld', 'sdk']
LOAD_EXEFS_NAMES = PRIMARY_EXEFS_NAMES + ['subsdk%d' % i for i in range(10)]
ALL_EXEFS_NAMES = LOAD_EXEFS_NAMES + ['main.npdm']
def get_load_formats(li, path):
li.seek(0)
if li.read(4) == 'NSO0':
if 'sdk' in os.path.basename(path):
yield { 'format': SDK_FORMAT, 'options': idaapi.ACCEPT_FIRST }
yield { 'format': NSO_FORMAT }
else:
yield { 'format': NSO_FORMAT, 'options': idaapi.ACCEPT_FIRST }
yield { 'format': SDK_FORMAT }
li.seek(0)
if li.read(4) == 'KIP1':
yield { 'format': KIP_FORMAT, 'options': idaapi.ACCEPT_FIRST }
li.seek(0x10)
if li.read(4) == 'NRO0':
yield { 'format': NRO_FORMAT, 'options': idaapi.ACCEPT_FIRST }
elif looks_like_memory_dump(li):
yield { 'format': RAW_FORMAT, 'options': idaapi.ACCEPT_FIRST }
yield { 'format': RAW_SDK_FORMAT }
if os.path.basename(path) in ALL_EXEFS_NAMES:
dirname = os.path.dirname(path)
if all(os.path.exists(os.path.join(dirname, i)) for i in PRIMARY_EXEFS_NAMES):
yield { 'format': EXEFS_FORMAT }
yield { 'format': EXEFS_LOW_FORMAT }
# this is mostly just to work with the IDA API
accept_formats_list = None
accept_formats_index = 0
def accept_file(li, path):
global accept_formats_list
global accept_formats_index
if accept_formats_list is None:
accept_formats_list = list(get_load_formats(li, path))
accept_formats_index = 0
if accept_formats_index >= len(accept_formats_list):
accept_formats_list = None
accept_formats_index = 0
return 0
ret = accept_formats_list[accept_formats_index]
if not isinstance(ret, dict):
ret = { 'format': ret }
if 'options' not in ret:
ret['options'] = 1
if 'processor' not in ret:
ret['processor'] = 'arm'
ret['options'] |= 1 | idaapi.ACCEPT_CONTINUE
accept_formats_index += 1
return ret
def ida_make_offset(f, ea):
if f.armv7:
idc.MakeDword(ea)
else:
idc.MakeQword(ea)
idc.OpOff(ea, 0, 0)
def find_bl_targets(text_start, text_end):
targets = set()
for pco in xrange(0, text_end - text_start, 4):
pc = text_start + pco
d = Dword(pc)
if (d & 0xfc000000) == 0x94000000:
imm = d & 0x3ffffff
if imm & 0x2000000:
imm |= ~0x1ffffff
if 0 <= imm <= 2:
continue
target = pc + imm * 4
if target >= text_start and target < text_end:
targets.add(target)
return targets
def load_file(li, neflags, fmt):
idaapi.set_processor_type('arm', SETPROC_ALL|SETPROC_FATAL)
options = FORMAT_OPTIONS[fmt]
if OPT_EXEFS_LOAD in options:
ret = load_as_exefs(li, options)
else:
ret = load_one_file(li, options, 0)
eh_parse = idaapi.find_plugin('eh_parse', True)
if eh_parse:
print 'eh_parse ->', idaapi.run_plugin(eh_parse, 0)
else:
print 'warning: eh_parse missing'
return ret
def load_as_exefs(li, options):
dirname = os.path.dirname(idc.get_input_file_path())
binaries = LOAD_EXEFS_NAMES
binaries = [os.path.join(dirname, i) for i in binaries]
binaries = [i for i in binaries if os.path.exists(i)]
for idx, fname in enumerate(binaries):
with open(fname, 'rb') as f:
if not load_one_file(f, options, idx, os.path.basename(fname)):
return False
return True
def load_one_file(li, options, idx, basename=None):
bypass_plt = OPT_BYPASS_PLT in options
f = load_nxo(li)
if idx == 0:
if f.armv7:
idc.SetShortPrm(idc.INF_LFLAGS, idc.GetShortPrm(idc.INF_LFLAGS) | idc.LFLG_PC_FLAT)
else:
idc.SetShortPrm(idc.INF_LFLAGS, idc.GetShortPrm(idc.INF_LFLAGS) | idc.LFLG_64BIT)
idc.SetCharPrm(idc.INF_DEMNAMES, idaapi.DEMNAM_GCC3)
idaapi.set_compiler_id(idaapi.COMP_GNU)
idaapi.add_til2('gnulnx_arm' if f.armv7 else 'gnulnx_arm64', 1)
# don't create tails
idc.set_inf_attr(idc.INF_AF, idc.get_inf_attr(idc.INF_AF) & ~idc.AF_FTAIL)
if OPT_LOAD_31_BIT in options:
loadbase = 0x8000000
step = 0x1000000
elif f.armv7:
loadbase = 0x60000000
step = 0x10000000
else:
loadbase = 0x7100000000
step = 0x100000000
loadbase += idx * step
f.binfile.seek(0)
as_string = f.binfile.read(f.bssoff)
idaapi.mem2base(as_string, loadbase)
seg_prefix = basename if basename is not None else ''
for start, end, name, kind in f.sections:
if name.startswith('.got'):
kind = 'CONST'
idaapi.add_segm(0, loadbase+start, loadbase+end, seg_prefix+name, kind)
segm = idaapi.get_segm_by_name(seg_prefix+name)
if kind == 'CONST':
segm.perm = idaapi.SEGPERM_READ
elif kind == 'CODE':
segm.perm = idaapi.SEGPERM_READ | idaapi.SEGPERM_EXEC
elif kind == 'DATA':
segm.perm = idaapi.SEGPERM_READ | idaapi.SEGPERM_WRITE
elif kind == 'BSS':
segm.perm = idaapi.SEGPERM_READ | idaapi.SEGPERM_WRITE
idaapi.update_segm(segm)
idaapi.set_segm_addressing(segm, 1 if f.armv7 else 2)
# do imports
# TODO: can we make imports show up in "Imports" window?
undef_count = 0
for s in f.symbols:
if not s.shndx and s.name:
undef_count += 1
last_ea = max(loadbase + end for start, end, name, kind in f.sections)
undef_entry_size = 8
undef_ea = ((last_ea + 0xFFF) & ~0xFFF) + undef_entry_size # plus 8 so we don't end up on the "end" symbol
undef_seg = basename + '.UNDEF' if basename is not None else 'UNDEF'
idaapi.add_segm(0, undef_ea, undef_ea+undef_count*undef_entry_size, undef_seg, 'XTRN')
segm = idaapi.get_segm_by_name(undef_seg)
segm.type = idaapi.SEG_XTRN
idaapi.update_segm(segm)
for i,s in enumerate(f.symbols):
if not s.shndx and s.name:
idc.MakeQword(undef_ea)
idaapi.do_name_anyway(undef_ea, s.name)
s.resolved = undef_ea
undef_ea += undef_entry_size
elif i != 0:
assert s.shndx
s.resolved = loadbase + s.value
if s.name:
if s.type == STT_FUNC:
idaapi.add_entry(s.resolved, s.resolved, s.name, 0)
else:
idaapi.do_name_anyway(s.resolved, s.name)
else:
# NULL symbol
s.resolved = 0
funcs = set()
for s in f.symbols:
if s.name and s.shndx and s.value:
if s.type == STT_FUNC:
funcs.add(loadbase+s.value)
symend = loadbase+s.value+s.size
if Dword(symend) != 0:
funcs.add(symend)
got_name_lookup = {}
for offset, r_type, sym, addend in f.relocations:
target = offset + loadbase
if r_type in (R_ARM_GLOB_DAT, R_ARM_JUMP_SLOT, R_ARM_ABS32):
if not sym:
print 'error: relocation at %X failed' % target
else:
idaapi.put_long(target, sym.resolved)
elif r_type == R_ARM_RELATIVE:
idaapi.put_long(target, idaapi.get_long(target) + loadbase)
elif r_type in (R_AARCH64_GLOB_DAT, R_AARCH64_JUMP_SLOT, R_AARCH64_ABS64):
idaapi.put_qword(target, sym.resolved + addend)
if addend == 0:
got_name_lookup[offset] = sym.name
elif r_type == R_AARCH64_RELATIVE:
idaapi.put_qword(target, loadbase + addend)
if addend < f.textsize:
funcs.add(loadbase + addend)
elif r_type == R_FAKE_RELR:
assert not f.armv7 # TODO
addend = idaapi.get_qword(target)
idaapi.put_qword(target, addend + loadbase)
if addend < f.textsize:
funcs.add(loadbase + addend)
else:
print 'TODO r_type %d' % (r_type,)
ida_make_offset(f, target)
for func, target in f.plt_entries:
if target in got_name_lookup:
addr = loadbase + func
funcs.add(addr)
idaapi.do_name_anyway(addr, got_name_lookup[target])
if not f.armv7:
funcs |= find_bl_targets(loadbase, loadbase+f.textsize)
if bypass_plt:
plt_lookup = f.plt_lookup
for pco in xrange(0, f.textsize, 4):
pc = loadbase + pco
d = Dword(pc)
if (d & 0x7c000000) == (0x94000000 & 0x7c000000):
imm = d & 0x3ffffff
if imm & 0x2000000:
imm |= ~0x1ffffff
if 0 <= imm <= 2:
continue
target = (pc + imm * 4) - loadbase
if target in plt_lookup:
new_target = plt_lookup[target] + loadbase
new_instr = (d & ~0x3ffffff) | (((new_target - pc) / 4) & 0x3ffffff)
idaapi.put_long(pc, new_instr)
for pco in xrange(0, f.textsize, 4):
pc = loadbase + pco
d = Dword(pc)
if d == 0x14000001:
funcs.add(pc + 4)
for pc, _ in f.eh_table:
funcs.add(loadbase + pc)
for addr in sorted(funcs, reverse=True):
idaapi.auto_make_proc(addr)
return 1