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-rw-r--r--src/miasm/arch/msp430/sem.py509
1 files changed, 509 insertions, 0 deletions
diff --git a/src/miasm/arch/msp430/sem.py b/src/miasm/arch/msp430/sem.py
new file mode 100644
index 00000000..d4d3221b
--- /dev/null
+++ b/src/miasm/arch/msp430/sem.py
@@ -0,0 +1,509 @@
+#-*- coding:utf-8 -*-
+
+from miasm.expression.expression import *
+from miasm.arch.msp430.regs import *
+from miasm.arch.msp430.arch import mn_msp430
+from miasm.ir.ir import Lifter
+
+
+# Utils
+def hex2bcd(val):
+    "Return val as BCD"
+    try:
+        return int("%x" % val, 10)
+    except ValueError:
+        raise NotImplementedError("Not defined behaviour")
+
+
+def bcd2hex(val):
+    "Return the hex value of a BCD"
+    try:
+        return int("0x%d" % val, 16)
+    except ValueError:
+        raise NotImplementedError("Not defined behaviour")
+
+
+def reset_sr_res():
+    return [ExprAssign(res, ExprInt(0, 7))]
+
+
+def update_flag_cf_inv_zf(a):
+    return [ExprAssign(cf, ExprCond(a, ExprInt(1, 1), ExprInt(0, 1)))]
+
+
+def update_flag_zf_eq(a, b):
+    return [ExprAssign(zf, ExprOp("FLAG_EQ_CMP", a, b))]
+
+
+def update_flag_zf(a):
+    return [ExprAssign(zf, ExprOp("FLAG_EQ", a))]
+
+
+def update_flag_nf(arg):
+    return [
+        ExprAssign(
+            nf,
+            ExprOp("FLAG_SIGN_SUB", arg, ExprInt(0, arg.size))
+        )
+    ]
+
+
+def update_flag_add_cf(op1, op2, res):
+    "Compute cf in @res = @op1 + @op2"
+    return [ExprAssign(cf, ExprOp("FLAG_ADD_CF", op1, op2))]
+
+
+def update_flag_add_of(op1, op2, res):
+    "Compute of in @res = @op1 + @op2"
+    return [ExprAssign(of, ExprOp("FLAG_ADD_OF", op1, op2))]
+
+
+# checked: ok for sbb add because b & c before +cf
+def update_flag_sub_cf(op1, op2, res):
+    "Compote CF in @op1 - @op2"
+    return [ExprAssign(cf, ExprOp("FLAG_SUB_CF", op1, op2) ^ ExprInt(1, 1))]
+
+
+def update_flag_sub_of(op1, op2, res):
+    "Compote OF in @res = @op1 - @op2"
+    return [ExprAssign(of, ExprOp("FLAG_SUB_OF", op1, op2))]
+
+
+def update_flag_arith_sub_zn(arg1, arg2):
+    """
+    Compute znp flags for (arg1 - arg2)
+    """
+    e = []
+    e += update_flag_zf_eq(arg1, arg2)
+    e += [ExprAssign(nf, ExprOp("FLAG_SIGN_SUB", arg1, arg2))]
+    return e
+
+
+def update_flag_arith_add_zn(arg1, arg2):
+    """
+    Compute zf and nf flags for (arg1 + arg2)
+    """
+    e = []
+    e += update_flag_zf_eq(arg1, -arg2)
+    e += [ExprAssign(nf, ExprOp("FLAG_SIGN_SUB", arg1, -arg2))]
+    return e
+
+
+
+def mng_autoinc(a, b, size):
+    e = []
+    if not (isinstance(a, ExprOp) and a.op == "autoinc"):
+        return e, a, b
+
+    a_r = a.args[0]
+    e.append(ExprAssign(a_r, a_r + ExprInt(size // 8, a_r.size)))
+    a = ExprMem(a_r, size)
+    if isinstance(b, ExprMem) and a_r in b.arg:
+        b = ExprMem(b.arg + ExprInt(size // 8, 16), b.size)
+    return e, a, b
+
+# Mnemonics
+
+
+def mov_b(ir, instr, a, b):
+    e, a, b = mng_autoinc(a, b, 8)
+    if isinstance(b, ExprMem):
+        b = ExprMem(b.arg, 8)
+        a = a[:8]
+    else:
+        a = a[:8].zeroExtend(16)
+    e.append(ExprAssign(b, a))
+    return e, []
+
+
+def mov_w(ir, instr, a, b):
+    e, a, b = mng_autoinc(a, b, 16)
+    e.append(ExprAssign(b, a))
+    if b == ir.pc:
+        e.append(ExprAssign(ir.IRDst, a))
+    return e, []
+
+
+def and_b(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 8)
+    arg1, arg2 = arg1[:8], arg2[:8]
+    res = arg1 & arg2
+    e.append(ExprAssign(b, res.zeroExtend(16)))
+
+    e += [ExprAssign(zf, ExprOp('FLAG_EQ_AND', arg1, arg2))]
+    e += [ExprAssign(nf, ExprOp("FLAG_SIGN_SUB", res, ExprInt(0, res.size)))]
+    e += reset_sr_res()
+    e += update_flag_cf_inv_zf(res)
+    e += [ExprAssign(of, ExprInt(0, 1))]
+
+    return e, []
+
+
+def and_w(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 16)
+    res = arg1 & arg2
+    e.append(ExprAssign(arg2, res))
+
+    e += [ExprAssign(zf, ExprOp('FLAG_EQ_AND', arg1, arg2))]
+    e += [ExprAssign(nf, ExprOp("FLAG_SIGN_SUB", res, ExprInt(0, res.size)))]
+    e += reset_sr_res()
+    e += update_flag_cf_inv_zf(res)
+    e += [ExprAssign(of, ExprInt(0, 1))]
+
+    return e, []
+
+
+def bic_b(ir, instr, a, b):
+    e, a, b = mng_autoinc(a, b, 8)
+    c = (a[:8] ^ ExprInt(0xff, 8)) & b[:8]
+    c = c.zeroExtend(b.size)
+    e.append(ExprAssign(b, c))
+    return e, []
+
+
+def bic_w(ir, instr, a, b):
+    e, a, b = mng_autoinc(a, b, 16)
+    if b == SR:
+        # Special case
+        if a.is_int(1):
+            # cf
+            e.append(ExprAssign(cf, ExprInt(0, 1)))
+            return e, []
+    c = (a ^ ExprInt(0xffff, 16)) & b
+    e.append(ExprAssign(b, c))
+    return e, []
+
+
+def bis_w(ir, instr, a, b):
+    e, a, b = mng_autoinc(a, b, 16)
+    c = a | b
+    e.append(ExprAssign(b, c))
+    return e, []
+
+
+def bit_w(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 16)
+    res = arg1 & arg2
+
+    e += [ExprAssign(zf, ExprOp('FLAG_EQ_AND', arg1, arg2))]
+    e += [ExprAssign(nf, ExprOp("FLAG_SIGN_SUB", res, ExprInt(0, res.size)))]
+    e += reset_sr_res()
+    e += update_flag_cf_inv_zf(res)
+    e += [ExprAssign(of, ExprInt(0, 1))]
+
+    return e, []
+
+
+def sub_w(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 16)
+    res = arg2 - arg1
+
+    e.append(ExprAssign(b, res))
+
+    e += update_flag_arith_sub_zn(arg2, arg1)
+    e += update_flag_sub_cf(arg2, arg1, res)
+    e += update_flag_sub_of(arg2, arg1, res)
+    e += reset_sr_res()
+
+    # micrcorruption
+    # e += update_flag_sub_of(a, b, c)
+    # e += update_flag_sub_of(b, a, c)
+    return e, []
+
+
+def add_b(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 8)
+    if isinstance(arg2, ExprMem):
+        arg2 = ExprMem(arg2.arg, 8)
+    else:
+        arg2 = arg2[:8]
+    arg1 = arg1[:8]
+    res = arg2 + arg1
+    e.append(ExprAssign(b, res))
+
+    e += update_flag_arith_add_zn(arg2, arg1)
+    e += update_flag_add_cf(arg2, arg1, res)
+    e += update_flag_add_of(arg2, arg1, res)
+    e += reset_sr_res()
+
+    return e, []
+
+
+def add_w(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 16)
+    res = arg2 + arg1
+    e.append(ExprAssign(b, res))
+
+    e += update_flag_arith_add_zn(arg2, arg1)
+    e += update_flag_add_cf(arg2, arg1, res)
+    e += update_flag_add_of(arg2, arg1, res)
+    e += reset_sr_res()
+
+    return e, []
+
+
+def dadd_w(ir, instr, a, b):
+    e, a, b = mng_autoinc(a, b, 16)
+    # TODO: microcorruption no carryflag
+    c = ExprOp("bcdadd", b, a)  # +zeroExtend(cf, 16))
+
+    e.append(ExprAssign(b, c))
+
+    # micrcorruption
+    e += update_flag_zf(a)
+    # e += update_flag_nf(a)
+    e += reset_sr_res()
+
+    e.append(ExprAssign(cf, ExprOp("bcdadd_cf", b, a)))  # +zeroExtend(cf, 16))))
+
+    # of : undefined
+    return e, []
+
+
+def xor_w(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 16)
+    res = arg2 ^ arg1
+    e.append(ExprAssign(b, res))
+
+    e += [ExprAssign(zf, ExprOp('FLAG_EQ_CMP', arg2, arg1))]
+    e += update_flag_nf(res)
+    e += reset_sr_res()
+    e += update_flag_cf_inv_zf(res)
+    e.append(ExprAssign(of, arg2.msb() & arg1.msb()))
+
+    return e, []
+
+
+def push_w(ir, instr, a):
+    e = []
+    e.append(ExprAssign(ExprMem(SP - ExprInt(2, 16), 16), a))
+    e.append(ExprAssign(SP, SP - ExprInt(2, 16)))
+    return e, []
+
+
+def call(ir, instr, a):
+    e, a, dummy = mng_autoinc(a, None, 16)
+
+    loc_next = ir.get_next_loc_key(instr)
+    loc_next_expr = ExprLoc(loc_next, 16)
+
+    e.append(ExprAssign(ExprMem(SP - ExprInt(2, 16), 16), loc_next_expr))
+    e.append(ExprAssign(SP, SP - ExprInt(2, 16)))
+    e.append(ExprAssign(PC, a))
+    e.append(ExprAssign(ir.IRDst, a))
+    return e, []
+
+
+def swpb(ir, instr, a):
+    e = []
+    x, y = a[:8], a[8:16]
+    e.append(ExprAssign(a, ExprCompose(y, x)))
+    return e, []
+
+
+def cmp_w(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 16)
+    res = arg2 - arg1
+
+    e += update_flag_arith_sub_zn(arg2, arg1)
+    e += update_flag_sub_cf(arg2, arg1, res)
+    e += update_flag_sub_of(arg2, arg1, res)
+    e += reset_sr_res()
+
+    return e, []
+
+
+def cmp_b(ir, instr, a, b):
+    e, arg1, arg2 = mng_autoinc(a, b, 8)
+    arg1, arg2 = arg1[:8], arg2[:8]
+    res = arg2 - arg1
+
+    e += update_flag_arith_sub_zn(arg2, arg1)
+    e += update_flag_sub_cf(arg2, arg1, res)
+    e += update_flag_sub_of(arg2, arg1, res)
+    e += reset_sr_res()
+
+    return e, []
+
+
+def jz(ir, instr, a):
+    loc_next = ir.get_next_loc_key(instr)
+    loc_next_expr = ExprLoc(loc_next, 16)
+    e = []
+    e.append(ExprAssign(PC, ExprCond(ExprOp("CC_EQ", zf), a, loc_next_expr)))
+    e.append(ExprAssign(ir.IRDst, ExprCond(ExprOp("CC_EQ", zf), a, loc_next_expr)))
+    return e, []
+
+
+def jnz(ir, instr, a):
+    loc_next = ir.get_next_loc_key(instr)
+    loc_next_expr = ExprLoc(loc_next, 16)
+    e = []
+    e.append(ExprAssign(PC, ExprCond(ExprOp("CC_EQ", zf), loc_next_expr, a)))
+    e.append(ExprAssign(ir.IRDst, ExprCond(ExprOp("CC_EQ", zf), loc_next_expr, a)))
+    return e, []
+
+
+def jl(ir, instr, a):
+    loc_next = ir.get_next_loc_key(instr)
+    loc_next_expr = ExprLoc(loc_next, 16)
+    e = []
+    e.append(ExprAssign(PC, ExprCond(ExprOp("CC_S<", nf, of), a, loc_next_expr)))
+    e.append(ExprAssign(ir.IRDst, ExprCond(ExprOp("CC_S<", nf, of), a, loc_next_expr)))
+    return e, []
+
+
+def jc(ir, instr, a):
+    loc_next = ir.get_next_loc_key(instr)
+    loc_next_expr = ExprLoc(loc_next, 16)
+    e = []
+    e.append(ExprAssign(PC, ExprCond(ExprOp("CC_U>=", cf ^ ExprInt(1, 1)), a, loc_next_expr)))
+    e.append(ExprAssign(ir.IRDst, ExprCond(ExprOp("CC_U>=", cf ^ ExprInt(1, 1)), a, loc_next_expr)))
+    return e, []
+
+
+def jnc(ir, instr, a):
+    loc_next = ir.get_next_loc_key(instr)
+    loc_next_expr = ExprLoc(loc_next, 16)
+    e = []
+    e.append(ExprAssign(PC, ExprCond(ExprOp("CC_U>=", cf ^ ExprInt(1, 1)), loc_next_expr, a)))
+    e.append(ExprAssign(ir.IRDst, ExprCond(ExprOp("CC_U>=", cf ^ ExprInt(1, 1)), loc_next_expr, a)))
+    return e, []
+
+
+def jge(ir, instr, a):
+    loc_next = ir.get_next_loc_key(instr)
+    loc_next_expr = ExprLoc(loc_next, 16)
+    e = []
+    e.append(ExprAssign(PC, ExprCond(ExprOp("CC_S>=", nf, of), a, loc_next_expr)))
+    e.append(ExprAssign(ir.IRDst, ExprCond(ExprOp("CC_S>=", nf, of), a, loc_next_expr)))
+    return e, []
+
+
+def jmp(ir, instr, a):
+    e = []
+    e.append(ExprAssign(PC, a))
+    e.append(ExprAssign(ir.IRDst, a))
+    return e, []
+
+
+def rrc_w(ir, instr, a):
+    e = []
+    c = ExprCompose(a[1:16], cf)
+    e.append(ExprAssign(a, c))
+    e.append(ExprAssign(cf, a[:1]))
+
+    # micrcorruption
+    e += update_flag_zf(a)
+    # e += update_flag_nf(a)
+    e += reset_sr_res()
+
+    e.append(ExprAssign(of, ExprInt(0, 1)))
+    return e, []
+
+
+def rra_w(ir, instr, a):
+    e = []
+    c = ExprCompose(a[1:16], a[15:16])
+    e.append(ExprAssign(a, c))
+    # TODO: error in disasm microcorruption?
+    # e.append(ExprAssign(cf, a[:1]))
+
+    # micrcorruption
+    e += update_flag_zf(a)
+    # e += update_flag_nf(a)
+    e += reset_sr_res()
+
+    e.append(ExprAssign(of, ExprInt(0, 1)))
+    return e, []
+
+
+def sxt(ir, instr, a):
+    e = []
+    c = a[:8].signExtend(16)
+    e.append(ExprAssign(a, c))
+
+    e += update_flag_zf(a)
+    e += update_flag_nf(a)
+    e += reset_sr_res()
+    e += update_flag_cf_inv_zf(c)
+    e.append(ExprAssign(of, ExprInt(0, 1)))
+
+    return e, []
+
+mnemo_func = {
+    "mov.b": mov_b,
+    "mov.w": mov_w,
+    "and.b": and_b,
+    "and.w": and_w,
+    "bic.b": bic_b,
+    "bic.w": bic_w,
+    "bis.w": bis_w,
+    "bit.w": bit_w,
+    "sub.w": sub_w,
+    "add.b": add_b,
+    "add.w": add_w,
+    "push.w": push_w,
+    "dadd.w": dadd_w,
+    "xor.w": xor_w,
+    "call": call,
+    "swpb": swpb,
+    "cmp.w": cmp_w,
+    "cmp.b": cmp_b,
+    "jz": jz,
+    "jnz": jnz,
+    "jl": jl,
+    "jc": jc,
+    "jnc": jnc,
+    "jmp": jmp,
+    "jge": jge,
+    "rrc.w": rrc_w,
+    "rra.w": rra_w,
+    "sxt": sxt,
+}
+
+
+composed_sr = ExprCompose(cf, zf, nf, gie, cpuoff, osc, scg0, scg1, of, res)
+
+
+def ComposeExprAssign(dst, src):
+    e = []
+    for start, arg in dst.iter_args():
+        e.append(ExprAssign(arg, src[start:start+arg.size]))
+    return e
+
+
+class Lifter_MSP430(Lifter):
+
+    def __init__(self, loc_db):
+        Lifter.__init__(self, mn_msp430, None, loc_db)
+        self.pc = PC
+        self.sp = SP
+        self.IRDst = ExprId('IRDst', 16)
+        self.addrsize = 16
+
+    def mod_pc(self, instr, instr_ir, extra_ir):
+        pass
+
+    def get_ir(self, instr):
+        args = instr.args
+        instr_ir, extra_ir = mnemo_func[instr.name](self, instr, *args)
+        self.mod_sr(instr, instr_ir, extra_ir)
+
+        return instr_ir, extra_ir
+
+    def mod_sr(self, instr, instr_ir, extra_ir):
+        for i, x in enumerate(instr_ir):
+            x = ExprAssign(x.dst, x.src.replace_expr({SR: composed_sr}))
+            instr_ir[i] = x
+            if x.dst != SR:
+                continue
+            xx = ComposeExprAssign(composed_sr, x.src)
+            instr_ir[i:i+1] = xx
+        for i, x in enumerate(instr_ir):
+            x = ExprAssign(x.dst, x.src.replace_expr(
+                {self.pc: ExprInt(instr.offset + instr.l, 16)}))
+            instr_ir[i] = x
+
+        if extra_ir:
+            raise NotImplementedError('not fully functional')