def _store_subscr_map(i, **kwargs):
v, m, k = i.src_vars
if not isinstance(m, _mem.ConstVar):
raise TranslationError(i.starts_line,
'Cannot subscript dynamically selected map')
return ([bi.Mov(bi.MapFdImm(m.val.fd), bi.Reg.R1)] +
_lea(i, k, bi.Reg.R2, **kwargs) + _lea(i, v, bi.Reg.R3, **kwargs) +
[
bi.Mov(bi.Imm(0), bi.Reg.R4),
bi.Call(bi.Imm(funcs.map_update_elem.num))
])
def _delete_subscr(i, **kwargs):
if issubclass(i.src_vars[1].var_type, ctypes.Array):
raise TranslationError(i.starts_line, 'Cannot delete from array')
m, k = i.src_vars
if not isinstance(m, _mem.ConstVar):
raise TranslationError(i.starts_line,
'Cannot delete from dynamically selected map')
return ([bi.Mov(bi.MapFdImm(m.val.fd), bi.Reg.R1)] +
_lea(i, k, bi.Reg.R2, **kwargs) +
[bi.Call(bi.Imm(funcs.map_delete_elem.num))])
def _call_function(i, **kwargs):
fn_var = i.src_vars[0]
if not isinstance(fn_var, _mem.ConstVar):
raise TranslationError(i.starts_line,
'Function may not be determined dynamically')
fn = fn_var.val
if isinstance(fn, funcs.PseudoFunc):
return _call_pseudo_function(i, **kwargs)
if not isinstance(fn, funcs.Func):
raise TranslationError(
i.starts_line, 'Function must be bpf function from py2bpf.funcs')
if fn.num_args != -1 and len(i.src_vars) != fn.num_args + 1:
raise TranslationError(
i.starts_line,
'Function "{}" expected {} arguments, got {}'.format(
fn.name, fn.num_args,
len(i.src_vars) - 1))
arg_regs = [bi.Reg.R1, bi.Reg.R2, bi.Reg.R3, bi.Reg.R4, bi.Reg.R5]
ret = []
# See explanation for this nonsense in funcs.py
arg_vars = []
for idx, var in enumerate(i.src_vars[1:]):
arg_vars.append(var)
if idx in fn.fill_array_size_args:
if issubclass(var.var_type, _types.Ptr):
length = ctypes.sizeof(var.var_type.var_type)
else:
length = ctypes.sizeof(var.var_type)
arg_vars.append(_mem.ConstVar(ctypes.c_uint64(length)))
# Put the arguments into appropriate registers
for arg, reg in zip(arg_vars, arg_regs):
if issubclass(arg.var_type, _ctypes._SimpleCData):
ret.extend(_mov(arg, reg))
else:
ret.extend(_lea(i, arg, reg, **kwargs))
# Call the function
ret.append(bi.Call(bi.Imm(fn.num)))
# Move the result, if we haven't ignored it
if len(i.dst_vars) > 0:
ret.extend(_mov(bi.Reg.R0, i.dst_vars[0]))
return ret
def _binary_subscr_map(i, **kwargs):
m, k, dv = i.src_vars[0], i.src_vars[1], i.dst_vars[0]
if not isinstance(m, _mem.ConstVar):
raise TranslationError(i.starts_line,
'Cannot subscript dynamically select map')
found, done = _make_tmp_label(), _make_tmp_label()
ret = []
ret.extend(_mov(bi.MapFdImm(m.val.fd), bi.Reg.R1))
ret.extend(_lea(i, k, bi.Reg.R2, **kwargs))
ret.extend([
bi.Call(bi.Imm(funcs.map_lookup_elem.num)),
])
if _is_ptr(dv.var_type):
sz = _get_cdata_size(dv.var_type)
ret.extend(_mov(bi.Reg.R0, dv))
else:
ret.extend([
bi.JumpIfNotEqual(bi.Imm(0), bi.Reg.R0, found),
])
# Move default value
dr = _get_var_reg(dv)
ret.extend(_mov_const(dv.var_type, m.val.DEFAULT_VALUE, dr, dv.offset))
ret.extend([
bi.Jump(done),
bi.Label(found),
])
# Primitives by value, others by reference
if issubclass(dv.var_type, _ctypes._SimpleCData):
sz = _get_cdata_size(dv.var_type)
ret.extend(_mov(bi.Mem(bi.Reg.R0, 0, sz), dv))
else:
ret.extend(_mov(bi.Reg.R0, dv))
ret.append(bi.Label(done))
return ret
