Module pandare.arch
This module contains architecture-specific code.
When the pandare.panda class is initialized, it will automatically
initialize a PandaArch class for the specified architecture in the variable
panda.arch.
Expand source code
'''
This module contains architecture-specific code.
When the `pandare.panda` class is initialized, it will automatically
initialize a PandaArch class for the specified architecture in the variable
`panda.arch`.
'''
import binascii
import struct
from .utils import telescope
class PandaArch():
'''
Base class for architecture-specific implementations for PANDA-supported architectures
'''
def __init__(self, panda):
'''
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
'''
self.panda = panda
self.reg_sp = None # Stack pointer register ID if stored in a register
self.reg_pc = None # PC register ID if stored in a register
self.reg_retaddr = None # Register ID that contains return address
self.reg_retval = None # convention: register name that contains return val
self.call_conventions = None # convention: ['reg_for_arg0', 'reg_for_arg1',...]
self.registers = {}
'''
Mapping of register names to indices into the appropriate CPUState array
'''
def _determine_bits(self):
'''
Determine bits and endianness for the panda object's architecture
'''
bits = None
endianness = None # String 'little' or 'big'
if self.panda.arch_name == "i386":
bits = 32
endianness = "little"
elif self.panda.arch_name == "x86_64":
bits = 64
endianness = "little"
elif self.panda.arch_name == "arm":
endianness = "little" # XXX add support for arm BE?
bits = 32
elif self.panda.arch_name == "aarch64":
bits = 64
endianness = "little" # XXX add support for arm BE?
elif self.panda.arch_name == "ppc":
bits = 32
endianness = "big"
elif self.panda.arch_name == "mips":
bits = 32
endianness = "big"
elif self.panda.arch_name == "mipsel":
bits = 32
endianness = "little"
elif self.panda.arch_name == "mips64":
bits = 64
endianness = "big"
elif self.panda.arch_name == "mips64el":
bits = 64
endianness = "little"
assert (bits is not None), f"Missing num_bits logic for {self.panda.arch_name}"
assert (endianness is not None), f"Missing endianness logic for {self.panda.arch_name}"
register_size = int(bits/8)
return bits, endianness, register_size
def get_reg(self, cpu, reg):
'''
Return value in a `reg` which is either a register name or index (e.g., "R0" or 0)
'''
if isinstance(reg, str):
reg = reg.upper()
if reg == 'PC':
return self.get_pc(cpu)
if reg not in self.registers.keys():
raise ValueError(f"Invalid register name {reg}")
else:
reg = self.registers[reg]
return self._get_reg_val(cpu, reg)
def _get_reg_val(self, cpu, idx):
'''
Virtual method. Must be implemented for each architecture to return contents of register specified by idx.
'''
raise NotImplementedError()
def set_reg(self, cpu, reg, val):
'''
Set register `reg` to a value where `reg` is either a register name or index (e.g., "R0" or 0)
'''
if isinstance(reg, str):
reg = reg.upper()
if reg not in self.registers.keys():
raise ValueError(f"Invalid register name {reg}")
else:
reg = self.registers[reg]
elif not isinstance(reg, int):
raise ValueError(f"Can't set register {reg}")
return self._set_reg_val(cpu, reg, val)
def _set_reg_val(self, cpu, idx, val):
'''
Virtual method. Must be implemented for each architecture to return contents of register specified by idx.
'''
raise NotImplementedError()
def get_pc(self, cpu):
'''
Returns the current program counter. Must be overloaded if self.reg_pc is None
'''
if self.reg_pc:
return self.get_reg(cpu, self.reg_pc)
else:
raise RuntimeError(f"get_pc unsupported for {self.panda.arch_name}")
def _get_arg_loc(self, idx, convention):
'''
return the name of the argument [idx] for the given arch with calling [convention]
'''
if self.call_conventions and convention in self.call_conventions:
if idx < len(self.call_conventions[convention]):
return self.call_conventions[convention][idx]
raise NotImplementedError(f"Unsupported argument number {idx}")
raise NotImplementedError(f"Unsupported convention {convention} for {type(self)}")
def _get_ret_val_reg(self, cpu, convention):
if self.reg_retval and convention in self.reg_retval:
return self.reg_retval[convention]
raise NotImplementedError(f"Unsupported get_retval for architecture {type(self)} {convention}")
def set_arg(self, cpu, idx, val, convention='default'):
'''
Set arg [idx] to [val] for given calling convention.
Note for syscalls we define arg[0] as syscall number and then 1-index the actual args
'''
argloc = self._get_arg_loc(idx, convention)
if self._is_stack_loc(argloc):
return self._write_stack(cpu, argloc, val)
else:
return self.set_reg(cpu, argloc, val)
def get_arg(self, cpu, idx, convention='default'):
'''
Return arg [idx] for given calling convention. This only works right as the guest
is calling or has called a function before register values are clobbered.
If arg[idx] should be stack-based, name it stack_0, stack_1... this allows mixed
conventions where some args are in registers and others are on the stack (i.e.,
mips32 syscalls).
When doing a stack-based read, this function may raise a ValueError if the memory
read fails (i.e., paged out, invalid address).
Note for syscalls we define arg[0] as syscall number and then 1-index the actual args
'''
argloc = self._get_arg_loc(idx, convention)
if self._is_stack_loc(argloc):
return self._read_stack(cpu, argloc)
else:
return self.get_reg(cpu, argloc)
@staticmethod
def _is_stack_loc(argloc):
'''
Given a name returned by self._get_arg_loc
check if it's the name of a stack offset
'''
return argloc.startswith("stack_")
def _write_stack(self, cpu, argloc, val):
'''
Given a name like stack_X, calculate where
the X-th value on the stack is, then write val
to that location
May raise a ValueError if the memory write fails
'''
if isinstance(val, int):
# Encode as word-size with endianness
bits, endianness, reg_sz = self._determine_bits()
val = val.to_bytes(reg_sz, byteorder=endianness)
if not isinstance(val, bytes):
raise ValueError("_write_stack needs an int or bytes")
# Stack based - get stack base, calculate offset, then try to read it
assert(self._is_stack_loc(argloc)), f"Can't get stack offset of {argloc}"
stack_idx = int(argloc.split("stack_")[1])
stack_base = self.get_reg(cpu, self.reg_sp)
offset = reg_sz * (stack_idx+1)
self.panda.virtual_memory_write(cpu, stack_base + offset, val)
def _read_stack(self, cpu, argloc):
'''
Given a name like stack_X, calculate where
the X-th value on the stack is, then read it out of
memory and return it.
May raise a ValueError if the memory read fails
'''
# Stack based - get stack base, calculate offset, then try to read it
assert(self._is_stack_loc(argloc)), f"Can't get stack offset of {argloc}"
stack_idx = int(argloc.split("stack_")[1])
stack_base = self.get_reg(cpu, self.reg_sp)
arg_sz = self.panda.bits // 8
offset = arg_sz * (stack_idx+1)
return self.panda.virtual_memory_read(cpu, stack_base + offset, arg_sz, fmt='int')
def set_retval(self, cpu, val, convention='default', failure=False):
'''
Set return val to [val] for given calling convention. This only works
right after a function call has returned, otherwise the register will contain
a different value.
If the given architecture returns failure/success in a second register (i.e., the A3
register for mips), set that according to the failure flag.
Note the failure argument only used by subclasses that overload this function. It's provided
in the signature here so it can be set by a caller without regard for the guest architecture.
'''
reg = self._get_ret_val_reg(cpu, convention)
return self.set_reg(cpu, reg, val)
def get_retval(self, cpu, convention='default'):
'''
Set return val to [val] for given calling convention. This only works
right after a function call has returned, otherwise the register will contain
a different value.
Return value from syscalls is signed
'''
reg = self._get_ret_val_reg(cpu, convention)
rv = self.get_reg(cpu, reg)
if convention == 'syscall':
rv = self.panda.from_unsigned_guest(rv)
return rv
def set_pc(self, cpu, val):
'''
Set the program counter. Must be overloaded if self.reg_pc is None
'''
if self.reg_pc:
return self.set_reg(cpu, self.reg_pc, val)
else:
raise RuntimeError(f"set_pc unsupported for {self.panda.arch_name}")
def dump_regs(self, cpu):
'''
Print (telescoping) each register and its values
'''
print(f"PC: {self.get_pc(cpu):x}")
for (regname, reg) in self.registers.items():
val = self.get_reg(cpu, reg)
print("{}: 0x{:x}".format(regname, val), end="\t")
telescope(self.panda, cpu, val)
def dump_stack(self, cpu, words=8):
'''
Print (telescoping) most recent `words` words on the stack (from stack pointer to stack pointer + `words`*word_size)
'''
base_reg_s = "SP"
base_reg_val = self.get_reg(cpu, self.reg_sp)
if base_reg_val == 0:
print("[WARNING: no stack pointer]")
return
word_size = int(self.panda.bits/8)
_, endianness, _ = self._determine_bits()
for word_idx in range(words):
try:
val_b = self.panda.virtual_memory_read(cpu, base_reg_val+word_idx*word_size, word_size)
val = int.from_bytes(val_b, byteorder=endianness)
print("[{}+0x{:0>2x}] == 0x{:0<8x}]: 0x{:0<8x}".format(base_reg_s, word_idx*word_size, base_reg_val+word_idx*word_size, val), end="\t")
telescope(self.panda, cpu, val)
except ValueError:
print("[{}+0x{:0>2x}] == [memory read error]".format(base_reg_s, word_idx*word_size))
def dump_state(self, cpu):
"""
Print registers and stack
"""
self.dump_regs(cpu)
self.dump_stack(cpu)
def get_args(self, cpu, num, convention='default'):
return [self.get_arg(cpu,i, convention) for i in range(num)]
class ArmArch(PandaArch):
'''
Register names and accessors for ARM
'''
def __init__(self, panda):
PandaArch.__init__(self, panda)
regnames = ["R0", "R1", "R2", "R3", "R4", "R5", "R6", "R7",
"R8", "R9", "R10", "R11", "R12", "SP", "LR", "IP"]
self.registers = {regnames[idx]: idx for idx in range(len(regnames)) }
"""Register array for ARM"""
self.reg_sp = regnames.index("SP")
self.reg_pc = regnames.index("IP")
self.reg_retaddr = regnames.index("LR")
self.reg_sp = regnames.index("SP")
self.reg_retaddr = regnames.index("LR")
self.call_conventions = {"arm32": ["R0", "R1", "R2", "R3"],
"syscall": ["R7", "R0", "R1", "R2", "R3", "R4", "R5"], # EABI
}
self.call_conventions['default'] = self.call_conventions['arm32']
self.call_conventions['linux_kernel'] = self.call_conventions['arm32']
self.reg_retval = {"default": "R0",
"syscall": "R0",
"linux_kernel": "R0"}
self.reg_pc = regnames.index("IP")
def _get_reg_val(self, cpu, reg):
'''
Return an arm register
'''
return cpu.env_ptr.regs[reg]
def _set_reg_val(self, cpu, reg, val):
'''
Set an arm register
'''
cpu.env_ptr.regs[reg] = val
def get_return_value(self, cpu):
'''
.. Deprecated:: use get_retval
'''
return self.get_retval(cpu)
def get_return_address(self, cpu):
'''
Looks up where ret will go
'''
return self.get_reg(cpu, "LR") & 0xFFFF_FFFE
class Aarch64Arch(PandaArch):
'''
Register names and accessors for ARM64 (Aarch64)
'''
def __init__(self, panda):
PandaArch.__init__(self, panda)
regnames = ["X0", "X1", "X2", "X3", "X4", "X5", "X6", "X7",
"XR", "X9", "X10", "X11", "X12", "X13", "X14",
"X15", "IP0", "IP1", "PR", "X19", "X20", "X21",
"X22", "X23", "X24", "X25", "X26", "X27",
"X28", "FP", "LR", "SP"]
self.reg_sp = regnames.index("SP")
self.registers = {regnames[idx]: idx for idx in range(len(regnames)) }
"""Register array for ARM"""
self.reg_sp = regnames.index("SP")
self.reg_retaddr = regnames.index("LR")
self.call_conventions = {"arm64": ["X0", "X1", "X2", "X3", "X4", "X5", "X6", "X7"],
"syscall": ["XR", "X0", "X1", "X2", "X3", "X4", "X5", "X6", "X7"]}
self.call_conventions['default'] = self.call_conventions['arm64']
self.call_conventions['linux_kernel'] = self.call_conventions['arm64']
self.reg_retval = {"default": "X0",
"syscall": "X0",
"linux_kernel": "X0"}
self.arm32 = ArmArch(panda)
def arm32_dec(f, name):
def wrap(*args, **kwargs):
# first check that we have an arg
if len(args) > 0:
# double check that it's a cpustate
cpu = args[0]
if "_cffi_backend" in str(type(cpu)):
# check if we're in arm32 mode
if cpu.env_ptr.aarch64 == 0:
func = getattr(self.arm32, name)
return func(*args, **kwargs)
return f(*args, **kwargs)
return wrap
for attr in dir(self):
if callable(getattr(self, attr)) and not attr.startswith('_'):
setattr(self, attr, arm32_dec(getattr(self, attr), attr))
def get_pc(self, cpu):
'''
Overloaded function to get aarch64 program counter.
Note the PC is not stored in a general purpose register.
'''
return cpu.env_ptr.pc
def set_pc(self, cpu, val):
'''
Overloaded function set AArch64 program counter
'''
cpu.env_ptr.pc = val
def _get_reg_val(self, cpu, reg):
'''
Return an aarch64 register
'''
if reg == 32:
print("WARNING: unsupported get sp for aarch64")
return 0
else:
return cpu.env_ptr.xregs[reg]
def _set_reg_val(self, cpu, reg, val):
'''
Set an aarch64 register
'''
cpu.env_ptr.xregs[reg] = val
def get_return_value(self, cpu):
'''
.. Deprecated:: use get_retval
'''
return self.get_retval(cpu)
def get_return_address(self, cpu):
'''
Looks up where ret will go
'''
return self.get_reg(cpu, "LR")
class MipsArch(PandaArch):
'''
Register names and accessors for 32-bit MIPS
'''
# Registers are:
'''
Register Number Conventional Name Usage
$0 $zero Hard-wired to 0
$1 $at Reserved for pseudo-instructions
$2 - $3 $v0, $v1 Return values from functions
$4 - $7 $a0 - $a3 Arguments to functions - not preserved by subprograms
$8 - $15 $t0 - $t7 Temporary data, not preserved by subprograms
$16 - $23 $s0 - $s7 Saved registers, preserved by subprograms
$24 - $25 $t8 - $t9 More temporary registers, not preserved by subprograms
$26 - $27 $k0 - $k1 Reserved for kernel. Do not use.
$28 $gp Global Area Pointer (base of global data segment)
$29 $sp Stack Pointer
$30 $fp Frame Pointer
$31 $ra Return Address
'''
def __init__(self, panda):
super().__init__(panda)
regnames = ['ZERO', 'AT', 'V0', 'V1', 'A0', 'A1', 'A2', 'A3',
'T0', 'T1', 'T2', 'T3', 'T4', 'T5', 'T6', 'T7',
'S0', 'S1', 'S2', 'S3', 'S4', 'S5', 'S6', 'S7',
'T8', 'T9', 'K0', 'K1', 'GP', 'SP', 'FP', 'RA']
self.reg_sp = regnames.index('SP')
self.reg_retaddr = regnames.index('RA')
# Default syscall/args are for mips o32
self.call_conventions = {"mips": ["A0", "A1", "A2", "A3"],
"syscall": ["V0", "A0", "A1", "A2", "A3", "stack_3", "stack_4", "stack_5", "stack_6"]} # XXX: Note it's not 0-indexed for stack args, I guess the syscall pushes stuff too
self.call_conventions['default'] = self.call_conventions['mips']
self.call_conventions['linux_kernel'] = self.call_conventions['mips']
self.reg_retval = {"default": "V0",
"syscall": 'V0',
"linux_kernel": 'V0'}
# note names must be stored uppercase for get/set reg to work case-insensitively
self.registers = {regnames[idx].upper(): idx for idx in range(len(regnames)) }
self.registers['R30'] = 30
def get_reg(self, cpu, reg):
'''
Overloaded function for a few mips specific registers
'''
if isinstance(reg, str):
env = cpu.env_ptr
reg = reg.upper()
if reg == 'HI':
return env.CP0_EntryHi
elif reg == 'LO':
return env.CP0_EntryLo0
elif reg.startswith('F') and reg[1:].isnumeric():
num = int(reg[1:])
_, endianness, _ = self._determine_bits()
return int.from_bytes(bytes(env.fpus[0].fpr[num]), byteorder=endianness)
elif reg == 'FCCR':
return env.fpus[0].fcr0
elif reg == 'DSPCONTROL':
return env.active_tc.DSPControl
elif reg == 'CP0_STATUS':
return env.CP0_Status
return super().get_reg(cpu, reg)
def get_pc(self, cpu):
'''
Overloaded function to return the MIPS current program counter
'''
return cpu.env_ptr.active_tc.PC
def set_pc(self, cpu, val):
'''
Overloaded function set the MIPS program counter
'''
cpu.env_ptr.active_tc.PC = val
def get_retval(self, cpu, convention='default'):
'''
Overloaded to incorporate error data from A3 register for syscalls.
If A3 is 1 and convention is syscall, *negate* the return value.
This matches behavior of other architecures (where -ERRNO is returned
on error)
'''
flip = 1
if convention == 'syscall' and self.get_reg(cpu, "A3") == 1:
flip = -1
return flip * super().get_retval(cpu)
def _get_reg_val(self, cpu, reg):
'''
Return a mips register
'''
return cpu.env_ptr.active_tc.gpr[reg]
def _set_reg_val(self, cpu, reg, val):
'''
Set a mips register
'''
cpu.env_ptr.active_tc.gpr[reg] = val
def get_return_value(self, cpu, convention='default'):
'''
.. Deprecated:: use get_retval
'''
return self.get_retval(cpu)
def get_call_return(self, cpu):
'''
.. Deprecated:: use get_return_address
'''
return self.get_return_address(cpu)
def get_return_address(self,cpu):
'''
looks up where ret will go
'''
return self.get_reg(cpu, "RA")
def set_retval(self, cpu, val, convention='default', failure=False):
'''
Overloaded function so when convention is syscall, user can control
the A3 register (which indicates syscall success/failure) in addition
to the syscall return value.
When convention == 'syscall', failure = False means A3 will bet set to 0.
Otherwise, it will be set to 1
'''
if convention == 'syscall':
# Set A3 register to indicate syscall success/failure
self.set_reg(cpu, 'a3', failure)
# If caller is trying to indicate error by setting a negative retval
# for a syscall, just make it positive with A3=1
if failure and self.panda.from_unsigned_guest(val) < 0:
val = -1 * self.panda.from_unsigned_guest(val)
return super().set_retval(cpu, val, convention)
class Mips64Arch(MipsArch):
'''
Register names and accessors for MIPS64. Inherits from MipsArch for everything
except the register name and call conventions.
'''
def __init__(self, panda):
super().__init__(panda)
regnames = ["zero", "at", "v0", "v1", "a0", "a1", "a2", "a3",
"a4", "a5", "a6", "a7", "t0", "t1", "t2", "t3",
"s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
"t8", "t9", "k0", "k1", "gp", "sp", "s8", "ra"]
self.reg_sp = regnames.index('sp')
self.reg_retaddr = regnames.index("ra")
# Default syscall/args are for mips 64/n32 - note the registers are different than 32
self.call_conventions = {"mips": ["A0", "A1", "A2", "A3"], # XXX Unsure?
"syscall": ["V0", "A0", "A1", "A2", "A3", "A4", "A5"]}
self.call_conventions['default'] = self.call_conventions['mips']
self.call_conventions['linux_kernel'] = self.call_conventions['mips']
self.reg_retval = {"default": "V0",
"syscall": 'V0'}
# note names must be stored uppercase for get/set reg to work case-insensitively
self.registers = {regnames[idx].upper(): idx for idx in range(len(regnames)) }
class PowerPCArch(PandaArch):
'''
Register names and accessors for ppc
'''
def __init__(self, panda):
super().__init__(panda)
regnames = ["r0", "sp", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11",
"r12", "r13", "r14", "r15", "r16", "r17", "r18", "r19", "r20", "r21", "r22",
"r23", "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31"]
self.reg_sp = regnames.index('sp')
self.registers = {regnames[idx].upper(): idx for idx in range(len(regnames)) }
self.registers_crf = ["CR0", "CR1", "CR2", "CR3", "CR4", "CR5", "CR6", "CR7"]
def get_pc(self, cpu):
'''
Overloaded function to return the ppc current program counter
'''
return cpu.env_ptr.nip
def set_pc(self, cpu, val):
'''
Overloaded function to set the ppc program counter
'''
cpu.env_ptr.nip = val
def _get_reg_val(self, cpu, reg):
'''
Return a ppc register
'''
return cpu.env_ptr.gpr[reg]
def _set_reg_val(self, cpu, reg, val):
'''
Set an x86_64 register
'''
cpu.env_ptr.gpr[reg] = val
def get_reg(self, cpu, reg):
reg = reg.upper()
env = cpu.env_ptr
if reg == "LR":
return env.lr
elif reg == "CTR":
return env.ctr
elif reg in self.registers_crf:
return env.crf[self.registers_crf.index(reg)]
else:
return super().get_reg(cpu, reg)
def set_reg(self, cpu, reg, val):
reg = reg.upper()
env = cpu.env_ptr
if reg == "LR":
env.lr = val
elif reg == "CTR":
env.ctr = val
elif reg in self.registers_crf:
env.crf[self.registers_crf.index(reg)] = val
else:
super().set_reg(cpu, reg, val)
class X86_64Arch(PandaArch):
'''
Register names and accessors for x86_64
'''
def __init__(self, panda):
super().__init__(panda)
# The only place I could find the R_ names is in tcg/i386/tcg-target.h:50
regnames = ['RAX', 'RCX', 'RDX', 'RBX', 'RSP', 'RBP', 'RSI', 'RDI',
'R8', 'R9', 'R10', 'R11', 'R12', 'R13', 'R14', 'R15']
# XXX Note order is A C D B, because that's how qemu does it
self.call_conventions = {'sysv': ['RDI', 'RSI', 'RDX', 'RCX', 'R8', 'R9'],
'syscall': ['RAX', 'RDI', 'RSI', 'RDX', 'R10', 'R8', 'R9']}
self.call_conventions['default'] = self.call_conventions['sysv']
self.call_conventions['linux_kernel'] = self.call_conventions['sysv']
self.reg_sp = regnames.index('RSP')
self.reg_retval = {'sysv': 'RAX',
'syscall': 'RAX',
'linux_kernel': 'RAX'}
self.reg_retval['default'] = self.reg_retval['sysv']
self.registers = {regnames[idx]: idx for idx in range(len(regnames)) }
# Internal state to support some of the weird x86-64 registers
self.reg_names_general = ['EAX', 'ECX', 'EDX', 'EBX', 'ESP', 'EBP', 'ESI', 'EDI']
self.reg_names_short = ['AX', 'CX', 'DX', 'BX', 'SP', 'BP', 'SI', 'DI']
self.reg_names_byte = ['AL', 'CL', 'DL', 'BL', 'AH', 'CH', 'DH', 'BH']
self.seg_names = ['ES', 'CS', 'SS', 'DS', 'FS', 'GS']
self.reg_names_mmr = ['LDT', 'TR', 'GDT', 'IDT']
def _get_segment_register(self, env, seg_name):
seg_idx = self.seg_names.index(seg_name)
return env.segs[seg_idx].base
def _get_general_purpose_register(self, env, reg_name, mask):
return env.regs[self.reg_names_general.index(reg_name)] & mask
def _set_segment_register(self, env, seg_name, value):
seg_idx = self.seg_names.index(seg_name)
env.segs[seg_idx].base = value
def _set_general_purpose_register(self, env, reg_name, value, mask):
reg_idx = self.reg_names_general.index(reg_name)
env.regs[reg_idx] = (env.regs[reg_idx] & ~mask) | (value & mask)
def get_pc(self, cpu):
'''
Overloaded function to return the x86_64 current program counter
'''
return cpu.env_ptr.eip
def get_retval(self, cpu, convention='default'):
'''
Overloaded to support FreeBSD syscall ABI
In that ABI, if eflags carry bit is set, an error has occured. To standardize
pandare.arch returns across architectures/ABIs, we indicate a failure by returnning
-ERRNO.
'''
error_flip = False
if convention == 'syscall' and self.panda.get_os_family() == 'OS_FREEBSD' and \
self.panda.libpanda.cpu_cc_compute_all(cpu.env_ptr, 1) & 1 == 1:
error_flip = True
return super().get_retval(cpu, convention) * (-1 if error_flip else 1)
def set_pc(self, cpu, val):
'''
Overloaded function to set the x86_64 program counter
'''
cpu.env_ptr.eip = val
def _get_mmr_val(self, cpu, reg):
reg = reg.lower()
sc = getattr(cpu.env_ptr, reg)
return (sc.selector, sc.base, sc.limit, sc.flags)
def _set_mmr_val(self, cpu, reg, val):
reg = reg.lower()
selector, base, limit, flags = val
sc = getattr(cpu.env_ptr, reg)
sc.selector = selector
sc.base = base
sc.limit = limit
sc.flags = flags
def _get_reg_val(self, cpu, reg):
'''
Return an x86_64 register
'''
return cpu.env_ptr.regs[reg]
def _set_reg_val(self, cpu, reg, val):
'''
Set an x86_64 register
'''
cpu.env_ptr.regs[reg] = val
def get_return_value(self, cpu):
'''
.. Deprecated:: use get_retval
'''
return self.get_retval(cpu)
def get_return_address(self, cpu):
'''
looks up where ret will go
'''
esp = self.get_reg(cpu, "RSP")
return self.panda.virtual_memory_read(cpu, esp, 8, fmt='int')
def get_reg(self, cpu, reg):
'''
X86_64 has a bunch of different ways to access registers. We support
the regular names, the 32 and 16 bit varations (e.g., EAX, AX, AL),
segment registers, and D/W/B style accesses to R8-R15
'''
if isinstance(reg, int):
# If reg is an int, it should be an offset into our register array
return self._get_reg_val(cpu, reg)
reg = reg.upper()
env = cpu.env_ptr
if reg in self.reg_names_mmr:
return self._get_mmr_val(cpu, reg)
if reg in self.seg_names:
return self._get_segment_register(env, reg)
elif reg in ['EFLAGS', 'RFLAGS']:
return env.eflags
elif reg in ['RIP', 'PC', 'EIP']:
pc = self.get_pc(cpu) # changes reg to 'IP' and re-calls this
if reg == 'EIP':
pc &= 0xFFFFFFFF
return pc
elif reg.startswith('XMM'):
raw_arr = env.xmm_regs[int(reg[3:].rstrip('HLQX'))]
_, endianness, _ = self._determine_bits()
if reg.endswith('lq'):
value_bytes = raw_arr[0:8] # Lower 64 bits
elif reg.endswith('hq'):
value_bytes = raw_arr[8:16] # Higher 64 bits
elif reg.endswith('hx'):
value_bytes = raw_arr[4:8] # Higher 32 bits of the lower 64 bits
else:
value_bytes = raw_arr[0:16] # Full 128 bits
return int.from_bytes(bytes(value_bytes), byteorder=endianness)
elif reg.startswith('MM'):
raise ValueError("MM registers unsupported")
elif reg.startswith('YMM'):
raise ValueError("YMM registers unsupported")
elif reg.startswith('CR'):
return env.cr[int(reg[2:])]
elif reg.startswith('R') and any([reg.endswith(x) for x in 'DWB']) and reg.strip('RDWB').isnumeric():
# R8-R15 can be accessed with D (double word), W (word) and B (byte)
# to select the lowest 32-bits, the lowest 16 bits, or the lowest 8 bits.
reg_idx = int(reg.strip('RDWB')) - 8
reg_suffix = reg[-1]
mask = {'D': 0xFFFFFFFF,
'W': 0xFFFF,
'B': 0xFF}[reg_suffix]
return env.regs[reg_idx] & mask
elif reg in self.reg_names_general:
return self._get_general_purpose_register(env, reg, 0xFFFFFFFF)
elif reg in self.reg_names_short:
return env.regs[self.reg_names_short.index(reg)] & 0xFFFF
elif reg in self.reg_names_byte:
reg_idx = self.reg_names_byte.index(reg)
if reg_idx > 3:
reg_idx -= 4
return (env.regs[reg_idx] >> 8) & 0xFF
else:
return env.regs[reg_idx] & 0xFF
else:
return super().get_reg(cpu, reg)
def set_reg(self, cpu, reg, val):
reg = reg.upper()
env = cpu.env_ptr
if reg in self.reg_names_mmr:
return self._set_mmr_val(cpu, reg, val)
elif reg in self.seg_names:
self._set_segment_register(env, reg, val)
elif reg in ['EFLAGS', 'RFLAGS']:
env.eflags = val
elif reg in ['RIP', 'PC']:
return self.set_pc(cpu, val) # changes reg to 'IP' and re-calls this
elif reg.startswith('XMM'):
env.xmm_regs[int(reg[3:])] = val
#raise NotImplementedError("XMM registers unsupported")
elif reg.startswith('MM'):
raise NotImplementedError("MM registers unsupported")
elif reg.startswith('YMM'):
raise NotImplementedError("YMM registers unsupported")
elif reg.startswith('CR'):
env.cr[int(reg[2:])] = val
elif reg.startswith('R') and any([reg.endswith(x) for x in 'DWB']):
# R8-R15 can be accessed with D (double word), W (word) and B (byte)
# to select the lowest 32-bits, the lowest 16 bits, or the lowest 8 bits.
reg_idx = int(reg.strip('RDWB')) - 8
reg_suffix = reg[-1]
mask = {'D': 0xFFFFFFFF,
'W': 0xFFFF,
'B': 0xFF}[reg_suffix]
env.regs[reg_idx] & mask
env.regs[reg_idx] = (env.regs[reg_idx] & ~mask) | (val & mask)
elif reg in self.reg_names_general:
self._set_general_purpose_register(env, reg, val, 0xFFFFFFFF)
elif reg in self.reg_names_short:
self._set_general_purpose_register(env, reg, val, 0xFFFF)
elif reg in self.reg_names_byte:
reg_idx = self.reg_names_byte.index(reg)
mask = 0xFF << (8 * (reg_idx > 3))
reg_idx %= 4
self._set_general_purpose_register(env, reg, val, mask)
else:
super().set_reg(cpu, reg, val)
class X86Arch(X86_64Arch):
'''
Register names and accessors for x86
'''
def __init__(self, panda):
super().__init__(panda)
regnames = ['EAX', 'ECX', 'EDX', 'EBX', 'ESP', 'EBP', 'ESI', 'EDI']
# XXX Note order is A C D B, because that's how qemu does it . See target/i386/cpu.h
# Note we don't set self.call_conventions because stack-based arg get/set is
# not yet supported
self.reg_retval = {"default": "EAX",
"syscall": "EAX",
"linux_kernel": "EAX"}
self.call_conventions = {"cdecl": [f"stack_{x}" for x in range(20)], # 20: arbitrary but big
"syscall": ["EAX", "EBX", "ECX", "EDX", "ESI", "EDI", "EBP"],
"linux_kernel": ["EAX", "EDX", "ECX", "stack_3", "stack_4", "stack_5", "stack_6"]}
self.call_conventions['default'] = self.call_conventions['cdecl']
self.reg_sp = regnames.index('ESP')
self.registers = {regnames[idx]: idx for idx in range(len(regnames)) }Classes
class Aarch64Arch (panda)-
Register names and accessors for ARM64 (Aarch64)
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
Expand source code
class Aarch64Arch(PandaArch): ''' Register names and accessors for ARM64 (Aarch64) ''' def __init__(self, panda): PandaArch.__init__(self, panda) regnames = ["X0", "X1", "X2", "X3", "X4", "X5", "X6", "X7", "XR", "X9", "X10", "X11", "X12", "X13", "X14", "X15", "IP0", "IP1", "PR", "X19", "X20", "X21", "X22", "X23", "X24", "X25", "X26", "X27", "X28", "FP", "LR", "SP"] self.reg_sp = regnames.index("SP") self.registers = {regnames[idx]: idx for idx in range(len(regnames)) } """Register array for ARM""" self.reg_sp = regnames.index("SP") self.reg_retaddr = regnames.index("LR") self.call_conventions = {"arm64": ["X0", "X1", "X2", "X3", "X4", "X5", "X6", "X7"], "syscall": ["XR", "X0", "X1", "X2", "X3", "X4", "X5", "X6", "X7"]} self.call_conventions['default'] = self.call_conventions['arm64'] self.call_conventions['linux_kernel'] = self.call_conventions['arm64'] self.reg_retval = {"default": "X0", "syscall": "X0", "linux_kernel": "X0"} self.arm32 = ArmArch(panda) def arm32_dec(f, name): def wrap(*args, **kwargs): # first check that we have an arg if len(args) > 0: # double check that it's a cpustate cpu = args[0] if "_cffi_backend" in str(type(cpu)): # check if we're in arm32 mode if cpu.env_ptr.aarch64 == 0: func = getattr(self.arm32, name) return func(*args, **kwargs) return f(*args, **kwargs) return wrap for attr in dir(self): if callable(getattr(self, attr)) and not attr.startswith('_'): setattr(self, attr, arm32_dec(getattr(self, attr), attr)) def get_pc(self, cpu): ''' Overloaded function to get aarch64 program counter. Note the PC is not stored in a general purpose register. ''' return cpu.env_ptr.pc def set_pc(self, cpu, val): ''' Overloaded function set AArch64 program counter ''' cpu.env_ptr.pc = val def _get_reg_val(self, cpu, reg): ''' Return an aarch64 register ''' if reg == 32: print("WARNING: unsupported get sp for aarch64") return 0 else: return cpu.env_ptr.xregs[reg] def _set_reg_val(self, cpu, reg, val): ''' Set an aarch64 register ''' cpu.env_ptr.xregs[reg] = val def get_return_value(self, cpu): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu) def get_return_address(self, cpu): ''' Looks up where ret will go ''' return self.get_reg(cpu, "LR")Ancestors
Methods
def get_pc(self, cpu)-
Overloaded function to get aarch64 program counter. Note the PC is not stored in a general purpose register.
Expand source code
def get_pc(self, cpu): ''' Overloaded function to get aarch64 program counter. Note the PC is not stored in a general purpose register. ''' return cpu.env_ptr.pc def get_return_address(self, cpu)-
Looks up where ret will go
Expand source code
def get_return_address(self, cpu): ''' Looks up where ret will go ''' return self.get_reg(cpu, "LR") def get_return_value(self, cpu)-
Deprecated: use get_retval
Expand source code
def get_return_value(self, cpu): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu) def set_pc(self, cpu, val)-
Overloaded function set AArch64 program counter
Expand source code
def set_pc(self, cpu, val): ''' Overloaded function set AArch64 program counter ''' cpu.env_ptr.pc = val
Inherited members
class ArmArch (panda)-
Register names and accessors for ARM
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
Expand source code
class ArmArch(PandaArch): ''' Register names and accessors for ARM ''' def __init__(self, panda): PandaArch.__init__(self, panda) regnames = ["R0", "R1", "R2", "R3", "R4", "R5", "R6", "R7", "R8", "R9", "R10", "R11", "R12", "SP", "LR", "IP"] self.registers = {regnames[idx]: idx for idx in range(len(regnames)) } """Register array for ARM""" self.reg_sp = regnames.index("SP") self.reg_pc = regnames.index("IP") self.reg_retaddr = regnames.index("LR") self.reg_sp = regnames.index("SP") self.reg_retaddr = regnames.index("LR") self.call_conventions = {"arm32": ["R0", "R1", "R2", "R3"], "syscall": ["R7", "R0", "R1", "R2", "R3", "R4", "R5"], # EABI } self.call_conventions['default'] = self.call_conventions['arm32'] self.call_conventions['linux_kernel'] = self.call_conventions['arm32'] self.reg_retval = {"default": "R0", "syscall": "R0", "linux_kernel": "R0"} self.reg_pc = regnames.index("IP") def _get_reg_val(self, cpu, reg): ''' Return an arm register ''' return cpu.env_ptr.regs[reg] def _set_reg_val(self, cpu, reg, val): ''' Set an arm register ''' cpu.env_ptr.regs[reg] = val def get_return_value(self, cpu): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu) def get_return_address(self, cpu): ''' Looks up where ret will go ''' return self.get_reg(cpu, "LR") & 0xFFFF_FFFEAncestors
Methods
def get_return_address(self, cpu)-
Looks up where ret will go
Expand source code
def get_return_address(self, cpu): ''' Looks up where ret will go ''' return self.get_reg(cpu, "LR") & 0xFFFF_FFFE def get_return_value(self, cpu)-
Deprecated: use get_retval
Expand source code
def get_return_value(self, cpu): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu)
Inherited members
class Mips64Arch (panda)-
Register names and accessors for MIPS64. Inherits from MipsArch for everything except the register name and call conventions.
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
Expand source code
class Mips64Arch(MipsArch): ''' Register names and accessors for MIPS64. Inherits from MipsArch for everything except the register name and call conventions. ''' def __init__(self, panda): super().__init__(panda) regnames = ["zero", "at", "v0", "v1", "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7", "t0", "t1", "t2", "t3", "s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7", "t8", "t9", "k0", "k1", "gp", "sp", "s8", "ra"] self.reg_sp = regnames.index('sp') self.reg_retaddr = regnames.index("ra") # Default syscall/args are for mips 64/n32 - note the registers are different than 32 self.call_conventions = {"mips": ["A0", "A1", "A2", "A3"], # XXX Unsure? "syscall": ["V0", "A0", "A1", "A2", "A3", "A4", "A5"]} self.call_conventions['default'] = self.call_conventions['mips'] self.call_conventions['linux_kernel'] = self.call_conventions['mips'] self.reg_retval = {"default": "V0", "syscall": 'V0'} # note names must be stored uppercase for get/set reg to work case-insensitively self.registers = {regnames[idx].upper(): idx for idx in range(len(regnames)) }Ancestors
Inherited members
class MipsArch (panda)-
Register names and accessors for 32-bit MIPS
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
Expand source code
class MipsArch(PandaArch): ''' Register names and accessors for 32-bit MIPS ''' # Registers are: ''' Register Number Conventional Name Usage $0 $zero Hard-wired to 0 $1 $at Reserved for pseudo-instructions $2 - $3 $v0, $v1 Return values from functions $4 - $7 $a0 - $a3 Arguments to functions - not preserved by subprograms $8 - $15 $t0 - $t7 Temporary data, not preserved by subprograms $16 - $23 $s0 - $s7 Saved registers, preserved by subprograms $24 - $25 $t8 - $t9 More temporary registers, not preserved by subprograms $26 - $27 $k0 - $k1 Reserved for kernel. Do not use. $28 $gp Global Area Pointer (base of global data segment) $29 $sp Stack Pointer $30 $fp Frame Pointer $31 $ra Return Address ''' def __init__(self, panda): super().__init__(panda) regnames = ['ZERO', 'AT', 'V0', 'V1', 'A0', 'A1', 'A2', 'A3', 'T0', 'T1', 'T2', 'T3', 'T4', 'T5', 'T6', 'T7', 'S0', 'S1', 'S2', 'S3', 'S4', 'S5', 'S6', 'S7', 'T8', 'T9', 'K0', 'K1', 'GP', 'SP', 'FP', 'RA'] self.reg_sp = regnames.index('SP') self.reg_retaddr = regnames.index('RA') # Default syscall/args are for mips o32 self.call_conventions = {"mips": ["A0", "A1", "A2", "A3"], "syscall": ["V0", "A0", "A1", "A2", "A3", "stack_3", "stack_4", "stack_5", "stack_6"]} # XXX: Note it's not 0-indexed for stack args, I guess the syscall pushes stuff too self.call_conventions['default'] = self.call_conventions['mips'] self.call_conventions['linux_kernel'] = self.call_conventions['mips'] self.reg_retval = {"default": "V0", "syscall": 'V0', "linux_kernel": 'V0'} # note names must be stored uppercase for get/set reg to work case-insensitively self.registers = {regnames[idx].upper(): idx for idx in range(len(regnames)) } self.registers['R30'] = 30 def get_reg(self, cpu, reg): ''' Overloaded function for a few mips specific registers ''' if isinstance(reg, str): env = cpu.env_ptr reg = reg.upper() if reg == 'HI': return env.CP0_EntryHi elif reg == 'LO': return env.CP0_EntryLo0 elif reg.startswith('F') and reg[1:].isnumeric(): num = int(reg[1:]) _, endianness, _ = self._determine_bits() return int.from_bytes(bytes(env.fpus[0].fpr[num]), byteorder=endianness) elif reg == 'FCCR': return env.fpus[0].fcr0 elif reg == 'DSPCONTROL': return env.active_tc.DSPControl elif reg == 'CP0_STATUS': return env.CP0_Status return super().get_reg(cpu, reg) def get_pc(self, cpu): ''' Overloaded function to return the MIPS current program counter ''' return cpu.env_ptr.active_tc.PC def set_pc(self, cpu, val): ''' Overloaded function set the MIPS program counter ''' cpu.env_ptr.active_tc.PC = val def get_retval(self, cpu, convention='default'): ''' Overloaded to incorporate error data from A3 register for syscalls. If A3 is 1 and convention is syscall, *negate* the return value. This matches behavior of other architecures (where -ERRNO is returned on error) ''' flip = 1 if convention == 'syscall' and self.get_reg(cpu, "A3") == 1: flip = -1 return flip * super().get_retval(cpu) def _get_reg_val(self, cpu, reg): ''' Return a mips register ''' return cpu.env_ptr.active_tc.gpr[reg] def _set_reg_val(self, cpu, reg, val): ''' Set a mips register ''' cpu.env_ptr.active_tc.gpr[reg] = val def get_return_value(self, cpu, convention='default'): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu) def get_call_return(self, cpu): ''' .. Deprecated:: use get_return_address ''' return self.get_return_address(cpu) def get_return_address(self,cpu): ''' looks up where ret will go ''' return self.get_reg(cpu, "RA") def set_retval(self, cpu, val, convention='default', failure=False): ''' Overloaded function so when convention is syscall, user can control the A3 register (which indicates syscall success/failure) in addition to the syscall return value. When convention == 'syscall', failure = False means A3 will bet set to 0. Otherwise, it will be set to 1 ''' if convention == 'syscall': # Set A3 register to indicate syscall success/failure self.set_reg(cpu, 'a3', failure) # If caller is trying to indicate error by setting a negative retval # for a syscall, just make it positive with A3=1 if failure and self.panda.from_unsigned_guest(val) < 0: val = -1 * self.panda.from_unsigned_guest(val) return super().set_retval(cpu, val, convention)Ancestors
Subclasses
Methods
def get_call_return(self, cpu)-
Deprecated: use get_return_address
Expand source code
def get_call_return(self, cpu): ''' .. Deprecated:: use get_return_address ''' return self.get_return_address(cpu) def get_pc(self, cpu)-
Overloaded function to return the MIPS current program counter
Expand source code
def get_pc(self, cpu): ''' Overloaded function to return the MIPS current program counter ''' return cpu.env_ptr.active_tc.PC def get_reg(self, cpu, reg)-
Overloaded function for a few mips specific registers
Expand source code
def get_reg(self, cpu, reg): ''' Overloaded function for a few mips specific registers ''' if isinstance(reg, str): env = cpu.env_ptr reg = reg.upper() if reg == 'HI': return env.CP0_EntryHi elif reg == 'LO': return env.CP0_EntryLo0 elif reg.startswith('F') and reg[1:].isnumeric(): num = int(reg[1:]) _, endianness, _ = self._determine_bits() return int.from_bytes(bytes(env.fpus[0].fpr[num]), byteorder=endianness) elif reg == 'FCCR': return env.fpus[0].fcr0 elif reg == 'DSPCONTROL': return env.active_tc.DSPControl elif reg == 'CP0_STATUS': return env.CP0_Status return super().get_reg(cpu, reg) def get_return_address(self, cpu)-
looks up where ret will go
Expand source code
def get_return_address(self,cpu): ''' looks up where ret will go ''' return self.get_reg(cpu, "RA") def get_return_value(self, cpu, convention='default')-
Deprecated: use get_retval
Expand source code
def get_return_value(self, cpu, convention='default'): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu) def get_retval(self, cpu, convention='default')-
Overloaded to incorporate error data from A3 register for syscalls.
If A3 is 1 and convention is syscall, negate the return value. This matches behavior of other architecures (where -ERRNO is returned on error)
Expand source code
def get_retval(self, cpu, convention='default'): ''' Overloaded to incorporate error data from A3 register for syscalls. If A3 is 1 and convention is syscall, *negate* the return value. This matches behavior of other architecures (where -ERRNO is returned on error) ''' flip = 1 if convention == 'syscall' and self.get_reg(cpu, "A3") == 1: flip = -1 return flip * super().get_retval(cpu) def set_pc(self, cpu, val)-
Overloaded function set the MIPS program counter
Expand source code
def set_pc(self, cpu, val): ''' Overloaded function set the MIPS program counter ''' cpu.env_ptr.active_tc.PC = val def set_retval(self, cpu, val, convention='default', failure=False)-
Overloaded function so when convention is syscall, user can control the A3 register (which indicates syscall success/failure) in addition to the syscall return value.
When convention == 'syscall', failure = False means A3 will bet set to 0. Otherwise, it will be set to 1
Expand source code
def set_retval(self, cpu, val, convention='default', failure=False): ''' Overloaded function so when convention is syscall, user can control the A3 register (which indicates syscall success/failure) in addition to the syscall return value. When convention == 'syscall', failure = False means A3 will bet set to 0. Otherwise, it will be set to 1 ''' if convention == 'syscall': # Set A3 register to indicate syscall success/failure self.set_reg(cpu, 'a3', failure) # If caller is trying to indicate error by setting a negative retval # for a syscall, just make it positive with A3=1 if failure and self.panda.from_unsigned_guest(val) < 0: val = -1 * self.panda.from_unsigned_guest(val) return super().set_retval(cpu, val, convention)
Inherited members
class PandaArch (panda)-
Base class for architecture-specific implementations for PANDA-supported architectures
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
Expand source code
class PandaArch(): ''' Base class for architecture-specific implementations for PANDA-supported architectures ''' def __init__(self, panda): ''' Initialize a PANDA-supported architecture and hold a handle on the PANDA object ''' self.panda = panda self.reg_sp = None # Stack pointer register ID if stored in a register self.reg_pc = None # PC register ID if stored in a register self.reg_retaddr = None # Register ID that contains return address self.reg_retval = None # convention: register name that contains return val self.call_conventions = None # convention: ['reg_for_arg0', 'reg_for_arg1',...] self.registers = {} ''' Mapping of register names to indices into the appropriate CPUState array ''' def _determine_bits(self): ''' Determine bits and endianness for the panda object's architecture ''' bits = None endianness = None # String 'little' or 'big' if self.panda.arch_name == "i386": bits = 32 endianness = "little" elif self.panda.arch_name == "x86_64": bits = 64 endianness = "little" elif self.panda.arch_name == "arm": endianness = "little" # XXX add support for arm BE? bits = 32 elif self.panda.arch_name == "aarch64": bits = 64 endianness = "little" # XXX add support for arm BE? elif self.panda.arch_name == "ppc": bits = 32 endianness = "big" elif self.panda.arch_name == "mips": bits = 32 endianness = "big" elif self.panda.arch_name == "mipsel": bits = 32 endianness = "little" elif self.panda.arch_name == "mips64": bits = 64 endianness = "big" elif self.panda.arch_name == "mips64el": bits = 64 endianness = "little" assert (bits is not None), f"Missing num_bits logic for {self.panda.arch_name}" assert (endianness is not None), f"Missing endianness logic for {self.panda.arch_name}" register_size = int(bits/8) return bits, endianness, register_size def get_reg(self, cpu, reg): ''' Return value in a `reg` which is either a register name or index (e.g., "R0" or 0) ''' if isinstance(reg, str): reg = reg.upper() if reg == 'PC': return self.get_pc(cpu) if reg not in self.registers.keys(): raise ValueError(f"Invalid register name {reg}") else: reg = self.registers[reg] return self._get_reg_val(cpu, reg) def _get_reg_val(self, cpu, idx): ''' Virtual method. Must be implemented for each architecture to return contents of register specified by idx. ''' raise NotImplementedError() def set_reg(self, cpu, reg, val): ''' Set register `reg` to a value where `reg` is either a register name or index (e.g., "R0" or 0) ''' if isinstance(reg, str): reg = reg.upper() if reg not in self.registers.keys(): raise ValueError(f"Invalid register name {reg}") else: reg = self.registers[reg] elif not isinstance(reg, int): raise ValueError(f"Can't set register {reg}") return self._set_reg_val(cpu, reg, val) def _set_reg_val(self, cpu, idx, val): ''' Virtual method. Must be implemented for each architecture to return contents of register specified by idx. ''' raise NotImplementedError() def get_pc(self, cpu): ''' Returns the current program counter. Must be overloaded if self.reg_pc is None ''' if self.reg_pc: return self.get_reg(cpu, self.reg_pc) else: raise RuntimeError(f"get_pc unsupported for {self.panda.arch_name}") def _get_arg_loc(self, idx, convention): ''' return the name of the argument [idx] for the given arch with calling [convention] ''' if self.call_conventions and convention in self.call_conventions: if idx < len(self.call_conventions[convention]): return self.call_conventions[convention][idx] raise NotImplementedError(f"Unsupported argument number {idx}") raise NotImplementedError(f"Unsupported convention {convention} for {type(self)}") def _get_ret_val_reg(self, cpu, convention): if self.reg_retval and convention in self.reg_retval: return self.reg_retval[convention] raise NotImplementedError(f"Unsupported get_retval for architecture {type(self)} {convention}") def set_arg(self, cpu, idx, val, convention='default'): ''' Set arg [idx] to [val] for given calling convention. Note for syscalls we define arg[0] as syscall number and then 1-index the actual args ''' argloc = self._get_arg_loc(idx, convention) if self._is_stack_loc(argloc): return self._write_stack(cpu, argloc, val) else: return self.set_reg(cpu, argloc, val) def get_arg(self, cpu, idx, convention='default'): ''' Return arg [idx] for given calling convention. This only works right as the guest is calling or has called a function before register values are clobbered. If arg[idx] should be stack-based, name it stack_0, stack_1... this allows mixed conventions where some args are in registers and others are on the stack (i.e., mips32 syscalls). When doing a stack-based read, this function may raise a ValueError if the memory read fails (i.e., paged out, invalid address). Note for syscalls we define arg[0] as syscall number and then 1-index the actual args ''' argloc = self._get_arg_loc(idx, convention) if self._is_stack_loc(argloc): return self._read_stack(cpu, argloc) else: return self.get_reg(cpu, argloc) @staticmethod def _is_stack_loc(argloc): ''' Given a name returned by self._get_arg_loc check if it's the name of a stack offset ''' return argloc.startswith("stack_") def _write_stack(self, cpu, argloc, val): ''' Given a name like stack_X, calculate where the X-th value on the stack is, then write val to that location May raise a ValueError if the memory write fails ''' if isinstance(val, int): # Encode as word-size with endianness bits, endianness, reg_sz = self._determine_bits() val = val.to_bytes(reg_sz, byteorder=endianness) if not isinstance(val, bytes): raise ValueError("_write_stack needs an int or bytes") # Stack based - get stack base, calculate offset, then try to read it assert(self._is_stack_loc(argloc)), f"Can't get stack offset of {argloc}" stack_idx = int(argloc.split("stack_")[1]) stack_base = self.get_reg(cpu, self.reg_sp) offset = reg_sz * (stack_idx+1) self.panda.virtual_memory_write(cpu, stack_base + offset, val) def _read_stack(self, cpu, argloc): ''' Given a name like stack_X, calculate where the X-th value on the stack is, then read it out of memory and return it. May raise a ValueError if the memory read fails ''' # Stack based - get stack base, calculate offset, then try to read it assert(self._is_stack_loc(argloc)), f"Can't get stack offset of {argloc}" stack_idx = int(argloc.split("stack_")[1]) stack_base = self.get_reg(cpu, self.reg_sp) arg_sz = self.panda.bits // 8 offset = arg_sz * (stack_idx+1) return self.panda.virtual_memory_read(cpu, stack_base + offset, arg_sz, fmt='int') def set_retval(self, cpu, val, convention='default', failure=False): ''' Set return val to [val] for given calling convention. This only works right after a function call has returned, otherwise the register will contain a different value. If the given architecture returns failure/success in a second register (i.e., the A3 register for mips), set that according to the failure flag. Note the failure argument only used by subclasses that overload this function. It's provided in the signature here so it can be set by a caller without regard for the guest architecture. ''' reg = self._get_ret_val_reg(cpu, convention) return self.set_reg(cpu, reg, val) def get_retval(self, cpu, convention='default'): ''' Set return val to [val] for given calling convention. This only works right after a function call has returned, otherwise the register will contain a different value. Return value from syscalls is signed ''' reg = self._get_ret_val_reg(cpu, convention) rv = self.get_reg(cpu, reg) if convention == 'syscall': rv = self.panda.from_unsigned_guest(rv) return rv def set_pc(self, cpu, val): ''' Set the program counter. Must be overloaded if self.reg_pc is None ''' if self.reg_pc: return self.set_reg(cpu, self.reg_pc, val) else: raise RuntimeError(f"set_pc unsupported for {self.panda.arch_name}") def dump_regs(self, cpu): ''' Print (telescoping) each register and its values ''' print(f"PC: {self.get_pc(cpu):x}") for (regname, reg) in self.registers.items(): val = self.get_reg(cpu, reg) print("{}: 0x{:x}".format(regname, val), end="\t") telescope(self.panda, cpu, val) def dump_stack(self, cpu, words=8): ''' Print (telescoping) most recent `words` words on the stack (from stack pointer to stack pointer + `words`*word_size) ''' base_reg_s = "SP" base_reg_val = self.get_reg(cpu, self.reg_sp) if base_reg_val == 0: print("[WARNING: no stack pointer]") return word_size = int(self.panda.bits/8) _, endianness, _ = self._determine_bits() for word_idx in range(words): try: val_b = self.panda.virtual_memory_read(cpu, base_reg_val+word_idx*word_size, word_size) val = int.from_bytes(val_b, byteorder=endianness) print("[{}+0x{:0>2x}] == 0x{:0<8x}]: 0x{:0<8x}".format(base_reg_s, word_idx*word_size, base_reg_val+word_idx*word_size, val), end="\t") telescope(self.panda, cpu, val) except ValueError: print("[{}+0x{:0>2x}] == [memory read error]".format(base_reg_s, word_idx*word_size)) def dump_state(self, cpu): """ Print registers and stack """ self.dump_regs(cpu) self.dump_stack(cpu) def get_args(self, cpu, num, convention='default'): return [self.get_arg(cpu,i, convention) for i in range(num)]Subclasses
Instance variables
var registers-
Mapping of register names to indices into the appropriate CPUState array
Methods
def dump_regs(self, cpu)-
Print (telescoping) each register and its values
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def dump_regs(self, cpu): ''' Print (telescoping) each register and its values ''' print(f"PC: {self.get_pc(cpu):x}") for (regname, reg) in self.registers.items(): val = self.get_reg(cpu, reg) print("{}: 0x{:x}".format(regname, val), end="\t") telescope(self.panda, cpu, val) def dump_stack(self, cpu, words=8)-
Print (telescoping) most recent
wordswords on the stack (from stack pointer to stack pointer +words*word_size)Expand source code
def dump_stack(self, cpu, words=8): ''' Print (telescoping) most recent `words` words on the stack (from stack pointer to stack pointer + `words`*word_size) ''' base_reg_s = "SP" base_reg_val = self.get_reg(cpu, self.reg_sp) if base_reg_val == 0: print("[WARNING: no stack pointer]") return word_size = int(self.panda.bits/8) _, endianness, _ = self._determine_bits() for word_idx in range(words): try: val_b = self.panda.virtual_memory_read(cpu, base_reg_val+word_idx*word_size, word_size) val = int.from_bytes(val_b, byteorder=endianness) print("[{}+0x{:0>2x}] == 0x{:0<8x}]: 0x{:0<8x}".format(base_reg_s, word_idx*word_size, base_reg_val+word_idx*word_size, val), end="\t") telescope(self.panda, cpu, val) except ValueError: print("[{}+0x{:0>2x}] == [memory read error]".format(base_reg_s, word_idx*word_size)) def dump_state(self, cpu)-
Print registers and stack
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def dump_state(self, cpu): """ Print registers and stack """ self.dump_regs(cpu) self.dump_stack(cpu) def get_arg(self, cpu, idx, convention='default')-
Return arg [idx] for given calling convention. This only works right as the guest is calling or has called a function before register values are clobbered.
If arg[idx] should be stack-based, name it stack_0, stack_1… this allows mixed conventions where some args are in registers and others are on the stack (i.e., mips32 syscalls).
When doing a stack-based read, this function may raise a ValueError if the memory read fails (i.e., paged out, invalid address).
Note for syscalls we define arg[0] as syscall number and then 1-index the actual args
Expand source code
def get_arg(self, cpu, idx, convention='default'): ''' Return arg [idx] for given calling convention. This only works right as the guest is calling or has called a function before register values are clobbered. If arg[idx] should be stack-based, name it stack_0, stack_1... this allows mixed conventions where some args are in registers and others are on the stack (i.e., mips32 syscalls). When doing a stack-based read, this function may raise a ValueError if the memory read fails (i.e., paged out, invalid address). Note for syscalls we define arg[0] as syscall number and then 1-index the actual args ''' argloc = self._get_arg_loc(idx, convention) if self._is_stack_loc(argloc): return self._read_stack(cpu, argloc) else: return self.get_reg(cpu, argloc) def get_args(self, cpu, num, convention='default')-
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def get_args(self, cpu, num, convention='default'): return [self.get_arg(cpu,i, convention) for i in range(num)] def get_pc(self, cpu)-
Returns the current program counter. Must be overloaded if self.reg_pc is None
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def get_pc(self, cpu): ''' Returns the current program counter. Must be overloaded if self.reg_pc is None ''' if self.reg_pc: return self.get_reg(cpu, self.reg_pc) else: raise RuntimeError(f"get_pc unsupported for {self.panda.arch_name}") def get_reg(self, cpu, reg)-
Return value in a
regwhich is either a register name or index (e.g., "R0" or 0)Expand source code
def get_reg(self, cpu, reg): ''' Return value in a `reg` which is either a register name or index (e.g., "R0" or 0) ''' if isinstance(reg, str): reg = reg.upper() if reg == 'PC': return self.get_pc(cpu) if reg not in self.registers.keys(): raise ValueError(f"Invalid register name {reg}") else: reg = self.registers[reg] return self._get_reg_val(cpu, reg) def get_retval(self, cpu, convention='default')-
Set return val to [val] for given calling convention. This only works right after a function call has returned, otherwise the register will contain a different value.
Return value from syscalls is signed
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def get_retval(self, cpu, convention='default'): ''' Set return val to [val] for given calling convention. This only works right after a function call has returned, otherwise the register will contain a different value. Return value from syscalls is signed ''' reg = self._get_ret_val_reg(cpu, convention) rv = self.get_reg(cpu, reg) if convention == 'syscall': rv = self.panda.from_unsigned_guest(rv) return rv def set_arg(self, cpu, idx, val, convention='default')-
Set arg [idx] to [val] for given calling convention.
Note for syscalls we define arg[0] as syscall number and then 1-index the actual args
Expand source code
def set_arg(self, cpu, idx, val, convention='default'): ''' Set arg [idx] to [val] for given calling convention. Note for syscalls we define arg[0] as syscall number and then 1-index the actual args ''' argloc = self._get_arg_loc(idx, convention) if self._is_stack_loc(argloc): return self._write_stack(cpu, argloc, val) else: return self.set_reg(cpu, argloc, val) def set_pc(self, cpu, val)-
Set the program counter. Must be overloaded if self.reg_pc is None
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def set_pc(self, cpu, val): ''' Set the program counter. Must be overloaded if self.reg_pc is None ''' if self.reg_pc: return self.set_reg(cpu, self.reg_pc, val) else: raise RuntimeError(f"set_pc unsupported for {self.panda.arch_name}") def set_reg(self, cpu, reg, val)-
Set register
regto a value whereregis either a register name or index (e.g., "R0" or 0)Expand source code
def set_reg(self, cpu, reg, val): ''' Set register `reg` to a value where `reg` is either a register name or index (e.g., "R0" or 0) ''' if isinstance(reg, str): reg = reg.upper() if reg not in self.registers.keys(): raise ValueError(f"Invalid register name {reg}") else: reg = self.registers[reg] elif not isinstance(reg, int): raise ValueError(f"Can't set register {reg}") return self._set_reg_val(cpu, reg, val) def set_retval(self, cpu, val, convention='default', failure=False)-
Set return val to [val] for given calling convention. This only works right after a function call has returned, otherwise the register will contain a different value.
If the given architecture returns failure/success in a second register (i.e., the A3 register for mips), set that according to the failure flag.
Note the failure argument only used by subclasses that overload this function. It's provided in the signature here so it can be set by a caller without regard for the guest architecture.
Expand source code
def set_retval(self, cpu, val, convention='default', failure=False): ''' Set return val to [val] for given calling convention. This only works right after a function call has returned, otherwise the register will contain a different value. If the given architecture returns failure/success in a second register (i.e., the A3 register for mips), set that according to the failure flag. Note the failure argument only used by subclasses that overload this function. It's provided in the signature here so it can be set by a caller without regard for the guest architecture. ''' reg = self._get_ret_val_reg(cpu, convention) return self.set_reg(cpu, reg, val)
class PowerPCArch (panda)-
Register names and accessors for ppc
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
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class PowerPCArch(PandaArch): ''' Register names and accessors for ppc ''' def __init__(self, panda): super().__init__(panda) regnames = ["r0", "sp", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15", "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23", "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31"] self.reg_sp = regnames.index('sp') self.registers = {regnames[idx].upper(): idx for idx in range(len(regnames)) } self.registers_crf = ["CR0", "CR1", "CR2", "CR3", "CR4", "CR5", "CR6", "CR7"] def get_pc(self, cpu): ''' Overloaded function to return the ppc current program counter ''' return cpu.env_ptr.nip def set_pc(self, cpu, val): ''' Overloaded function to set the ppc program counter ''' cpu.env_ptr.nip = val def _get_reg_val(self, cpu, reg): ''' Return a ppc register ''' return cpu.env_ptr.gpr[reg] def _set_reg_val(self, cpu, reg, val): ''' Set an x86_64 register ''' cpu.env_ptr.gpr[reg] = val def get_reg(self, cpu, reg): reg = reg.upper() env = cpu.env_ptr if reg == "LR": return env.lr elif reg == "CTR": return env.ctr elif reg in self.registers_crf: return env.crf[self.registers_crf.index(reg)] else: return super().get_reg(cpu, reg) def set_reg(self, cpu, reg, val): reg = reg.upper() env = cpu.env_ptr if reg == "LR": env.lr = val elif reg == "CTR": env.ctr = val elif reg in self.registers_crf: env.crf[self.registers_crf.index(reg)] = val else: super().set_reg(cpu, reg, val)Ancestors
Methods
def get_pc(self, cpu)-
Overloaded function to return the ppc current program counter
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def get_pc(self, cpu): ''' Overloaded function to return the ppc current program counter ''' return cpu.env_ptr.nip def set_pc(self, cpu, val)-
Overloaded function to set the ppc program counter
Expand source code
def set_pc(self, cpu, val): ''' Overloaded function to set the ppc program counter ''' cpu.env_ptr.nip = val
Inherited members
class X86Arch (panda)-
Register names and accessors for x86
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
Expand source code
class X86Arch(X86_64Arch): ''' Register names and accessors for x86 ''' def __init__(self, panda): super().__init__(panda) regnames = ['EAX', 'ECX', 'EDX', 'EBX', 'ESP', 'EBP', 'ESI', 'EDI'] # XXX Note order is A C D B, because that's how qemu does it . See target/i386/cpu.h # Note we don't set self.call_conventions because stack-based arg get/set is # not yet supported self.reg_retval = {"default": "EAX", "syscall": "EAX", "linux_kernel": "EAX"} self.call_conventions = {"cdecl": [f"stack_{x}" for x in range(20)], # 20: arbitrary but big "syscall": ["EAX", "EBX", "ECX", "EDX", "ESI", "EDI", "EBP"], "linux_kernel": ["EAX", "EDX", "ECX", "stack_3", "stack_4", "stack_5", "stack_6"]} self.call_conventions['default'] = self.call_conventions['cdecl'] self.reg_sp = regnames.index('ESP') self.registers = {regnames[idx]: idx for idx in range(len(regnames)) }Ancestors
Inherited members
class X86_64Arch (panda)-
Register names and accessors for x86_64
Initialize a PANDA-supported architecture and hold a handle on the PANDA object
Expand source code
class X86_64Arch(PandaArch): ''' Register names and accessors for x86_64 ''' def __init__(self, panda): super().__init__(panda) # The only place I could find the R_ names is in tcg/i386/tcg-target.h:50 regnames = ['RAX', 'RCX', 'RDX', 'RBX', 'RSP', 'RBP', 'RSI', 'RDI', 'R8', 'R9', 'R10', 'R11', 'R12', 'R13', 'R14', 'R15'] # XXX Note order is A C D B, because that's how qemu does it self.call_conventions = {'sysv': ['RDI', 'RSI', 'RDX', 'RCX', 'R8', 'R9'], 'syscall': ['RAX', 'RDI', 'RSI', 'RDX', 'R10', 'R8', 'R9']} self.call_conventions['default'] = self.call_conventions['sysv'] self.call_conventions['linux_kernel'] = self.call_conventions['sysv'] self.reg_sp = regnames.index('RSP') self.reg_retval = {'sysv': 'RAX', 'syscall': 'RAX', 'linux_kernel': 'RAX'} self.reg_retval['default'] = self.reg_retval['sysv'] self.registers = {regnames[idx]: idx for idx in range(len(regnames)) } # Internal state to support some of the weird x86-64 registers self.reg_names_general = ['EAX', 'ECX', 'EDX', 'EBX', 'ESP', 'EBP', 'ESI', 'EDI'] self.reg_names_short = ['AX', 'CX', 'DX', 'BX', 'SP', 'BP', 'SI', 'DI'] self.reg_names_byte = ['AL', 'CL', 'DL', 'BL', 'AH', 'CH', 'DH', 'BH'] self.seg_names = ['ES', 'CS', 'SS', 'DS', 'FS', 'GS'] self.reg_names_mmr = ['LDT', 'TR', 'GDT', 'IDT'] def _get_segment_register(self, env, seg_name): seg_idx = self.seg_names.index(seg_name) return env.segs[seg_idx].base def _get_general_purpose_register(self, env, reg_name, mask): return env.regs[self.reg_names_general.index(reg_name)] & mask def _set_segment_register(self, env, seg_name, value): seg_idx = self.seg_names.index(seg_name) env.segs[seg_idx].base = value def _set_general_purpose_register(self, env, reg_name, value, mask): reg_idx = self.reg_names_general.index(reg_name) env.regs[reg_idx] = (env.regs[reg_idx] & ~mask) | (value & mask) def get_pc(self, cpu): ''' Overloaded function to return the x86_64 current program counter ''' return cpu.env_ptr.eip def get_retval(self, cpu, convention='default'): ''' Overloaded to support FreeBSD syscall ABI In that ABI, if eflags carry bit is set, an error has occured. To standardize pandare.arch returns across architectures/ABIs, we indicate a failure by returnning -ERRNO. ''' error_flip = False if convention == 'syscall' and self.panda.get_os_family() == 'OS_FREEBSD' and \ self.panda.libpanda.cpu_cc_compute_all(cpu.env_ptr, 1) & 1 == 1: error_flip = True return super().get_retval(cpu, convention) * (-1 if error_flip else 1) def set_pc(self, cpu, val): ''' Overloaded function to set the x86_64 program counter ''' cpu.env_ptr.eip = val def _get_mmr_val(self, cpu, reg): reg = reg.lower() sc = getattr(cpu.env_ptr, reg) return (sc.selector, sc.base, sc.limit, sc.flags) def _set_mmr_val(self, cpu, reg, val): reg = reg.lower() selector, base, limit, flags = val sc = getattr(cpu.env_ptr, reg) sc.selector = selector sc.base = base sc.limit = limit sc.flags = flags def _get_reg_val(self, cpu, reg): ''' Return an x86_64 register ''' return cpu.env_ptr.regs[reg] def _set_reg_val(self, cpu, reg, val): ''' Set an x86_64 register ''' cpu.env_ptr.regs[reg] = val def get_return_value(self, cpu): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu) def get_return_address(self, cpu): ''' looks up where ret will go ''' esp = self.get_reg(cpu, "RSP") return self.panda.virtual_memory_read(cpu, esp, 8, fmt='int') def get_reg(self, cpu, reg): ''' X86_64 has a bunch of different ways to access registers. We support the regular names, the 32 and 16 bit varations (e.g., EAX, AX, AL), segment registers, and D/W/B style accesses to R8-R15 ''' if isinstance(reg, int): # If reg is an int, it should be an offset into our register array return self._get_reg_val(cpu, reg) reg = reg.upper() env = cpu.env_ptr if reg in self.reg_names_mmr: return self._get_mmr_val(cpu, reg) if reg in self.seg_names: return self._get_segment_register(env, reg) elif reg in ['EFLAGS', 'RFLAGS']: return env.eflags elif reg in ['RIP', 'PC', 'EIP']: pc = self.get_pc(cpu) # changes reg to 'IP' and re-calls this if reg == 'EIP': pc &= 0xFFFFFFFF return pc elif reg.startswith('XMM'): raw_arr = env.xmm_regs[int(reg[3:].rstrip('HLQX'))] _, endianness, _ = self._determine_bits() if reg.endswith('lq'): value_bytes = raw_arr[0:8] # Lower 64 bits elif reg.endswith('hq'): value_bytes = raw_arr[8:16] # Higher 64 bits elif reg.endswith('hx'): value_bytes = raw_arr[4:8] # Higher 32 bits of the lower 64 bits else: value_bytes = raw_arr[0:16] # Full 128 bits return int.from_bytes(bytes(value_bytes), byteorder=endianness) elif reg.startswith('MM'): raise ValueError("MM registers unsupported") elif reg.startswith('YMM'): raise ValueError("YMM registers unsupported") elif reg.startswith('CR'): return env.cr[int(reg[2:])] elif reg.startswith('R') and any([reg.endswith(x) for x in 'DWB']) and reg.strip('RDWB').isnumeric(): # R8-R15 can be accessed with D (double word), W (word) and B (byte) # to select the lowest 32-bits, the lowest 16 bits, or the lowest 8 bits. reg_idx = int(reg.strip('RDWB')) - 8 reg_suffix = reg[-1] mask = {'D': 0xFFFFFFFF, 'W': 0xFFFF, 'B': 0xFF}[reg_suffix] return env.regs[reg_idx] & mask elif reg in self.reg_names_general: return self._get_general_purpose_register(env, reg, 0xFFFFFFFF) elif reg in self.reg_names_short: return env.regs[self.reg_names_short.index(reg)] & 0xFFFF elif reg in self.reg_names_byte: reg_idx = self.reg_names_byte.index(reg) if reg_idx > 3: reg_idx -= 4 return (env.regs[reg_idx] >> 8) & 0xFF else: return env.regs[reg_idx] & 0xFF else: return super().get_reg(cpu, reg) def set_reg(self, cpu, reg, val): reg = reg.upper() env = cpu.env_ptr if reg in self.reg_names_mmr: return self._set_mmr_val(cpu, reg, val) elif reg in self.seg_names: self._set_segment_register(env, reg, val) elif reg in ['EFLAGS', 'RFLAGS']: env.eflags = val elif reg in ['RIP', 'PC']: return self.set_pc(cpu, val) # changes reg to 'IP' and re-calls this elif reg.startswith('XMM'): env.xmm_regs[int(reg[3:])] = val #raise NotImplementedError("XMM registers unsupported") elif reg.startswith('MM'): raise NotImplementedError("MM registers unsupported") elif reg.startswith('YMM'): raise NotImplementedError("YMM registers unsupported") elif reg.startswith('CR'): env.cr[int(reg[2:])] = val elif reg.startswith('R') and any([reg.endswith(x) for x in 'DWB']): # R8-R15 can be accessed with D (double word), W (word) and B (byte) # to select the lowest 32-bits, the lowest 16 bits, or the lowest 8 bits. reg_idx = int(reg.strip('RDWB')) - 8 reg_suffix = reg[-1] mask = {'D': 0xFFFFFFFF, 'W': 0xFFFF, 'B': 0xFF}[reg_suffix] env.regs[reg_idx] & mask env.regs[reg_idx] = (env.regs[reg_idx] & ~mask) | (val & mask) elif reg in self.reg_names_general: self._set_general_purpose_register(env, reg, val, 0xFFFFFFFF) elif reg in self.reg_names_short: self._set_general_purpose_register(env, reg, val, 0xFFFF) elif reg in self.reg_names_byte: reg_idx = self.reg_names_byte.index(reg) mask = 0xFF << (8 * (reg_idx > 3)) reg_idx %= 4 self._set_general_purpose_register(env, reg, val, mask) else: super().set_reg(cpu, reg, val)Ancestors
Subclasses
Methods
def get_pc(self, cpu)-
Overloaded function to return the x86_64 current program counter
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def get_pc(self, cpu): ''' Overloaded function to return the x86_64 current program counter ''' return cpu.env_ptr.eip def get_reg(self, cpu, reg)-
X86_64 has a bunch of different ways to access registers. We support the regular names, the 32 and 16 bit varations (e.g., EAX, AX, AL), segment registers, and D/W/B style accesses to R8-R15
Expand source code
def get_reg(self, cpu, reg): ''' X86_64 has a bunch of different ways to access registers. We support the regular names, the 32 and 16 bit varations (e.g., EAX, AX, AL), segment registers, and D/W/B style accesses to R8-R15 ''' if isinstance(reg, int): # If reg is an int, it should be an offset into our register array return self._get_reg_val(cpu, reg) reg = reg.upper() env = cpu.env_ptr if reg in self.reg_names_mmr: return self._get_mmr_val(cpu, reg) if reg in self.seg_names: return self._get_segment_register(env, reg) elif reg in ['EFLAGS', 'RFLAGS']: return env.eflags elif reg in ['RIP', 'PC', 'EIP']: pc = self.get_pc(cpu) # changes reg to 'IP' and re-calls this if reg == 'EIP': pc &= 0xFFFFFFFF return pc elif reg.startswith('XMM'): raw_arr = env.xmm_regs[int(reg[3:].rstrip('HLQX'))] _, endianness, _ = self._determine_bits() if reg.endswith('lq'): value_bytes = raw_arr[0:8] # Lower 64 bits elif reg.endswith('hq'): value_bytes = raw_arr[8:16] # Higher 64 bits elif reg.endswith('hx'): value_bytes = raw_arr[4:8] # Higher 32 bits of the lower 64 bits else: value_bytes = raw_arr[0:16] # Full 128 bits return int.from_bytes(bytes(value_bytes), byteorder=endianness) elif reg.startswith('MM'): raise ValueError("MM registers unsupported") elif reg.startswith('YMM'): raise ValueError("YMM registers unsupported") elif reg.startswith('CR'): return env.cr[int(reg[2:])] elif reg.startswith('R') and any([reg.endswith(x) for x in 'DWB']) and reg.strip('RDWB').isnumeric(): # R8-R15 can be accessed with D (double word), W (word) and B (byte) # to select the lowest 32-bits, the lowest 16 bits, or the lowest 8 bits. reg_idx = int(reg.strip('RDWB')) - 8 reg_suffix = reg[-1] mask = {'D': 0xFFFFFFFF, 'W': 0xFFFF, 'B': 0xFF}[reg_suffix] return env.regs[reg_idx] & mask elif reg in self.reg_names_general: return self._get_general_purpose_register(env, reg, 0xFFFFFFFF) elif reg in self.reg_names_short: return env.regs[self.reg_names_short.index(reg)] & 0xFFFF elif reg in self.reg_names_byte: reg_idx = self.reg_names_byte.index(reg) if reg_idx > 3: reg_idx -= 4 return (env.regs[reg_idx] >> 8) & 0xFF else: return env.regs[reg_idx] & 0xFF else: return super().get_reg(cpu, reg) def get_return_address(self, cpu)-
looks up where ret will go
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def get_return_address(self, cpu): ''' looks up where ret will go ''' esp = self.get_reg(cpu, "RSP") return self.panda.virtual_memory_read(cpu, esp, 8, fmt='int') def get_return_value(self, cpu)-
Deprecated: use get_retval
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def get_return_value(self, cpu): ''' .. Deprecated:: use get_retval ''' return self.get_retval(cpu) def get_retval(self, cpu, convention='default')-
Overloaded to support FreeBSD syscall ABI In that ABI, if eflags carry bit is set, an error has occured. To standardize pandare.arch returns across architectures/ABIs, we indicate a failure by returnning -ERRNO.
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def get_retval(self, cpu, convention='default'): ''' Overloaded to support FreeBSD syscall ABI In that ABI, if eflags carry bit is set, an error has occured. To standardize pandare.arch returns across architectures/ABIs, we indicate a failure by returnning -ERRNO. ''' error_flip = False if convention == 'syscall' and self.panda.get_os_family() == 'OS_FREEBSD' and \ self.panda.libpanda.cpu_cc_compute_all(cpu.env_ptr, 1) & 1 == 1: error_flip = True return super().get_retval(cpu, convention) * (-1 if error_flip else 1) def set_pc(self, cpu, val)-
Overloaded function to set the x86_64 program counter
Expand source code
def set_pc(self, cpu, val): ''' Overloaded function to set the x86_64 program counter ''' cpu.env_ptr.eip = val
Inherited members