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IDAPython script to extract contents of global byte array in the FLARE-On Challenge #6
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from idaapi import * | |
GEN_REG = 0x1 | |
MEM_REF = 0x2 | |
BASE_INDEX = 0x3 | |
BASE_INDEX_DISP = 0x4 | |
IMMED = 0x5 | |
def doone(ea): | |
xrefs = [] | |
for xref in DataRefsTo(ea): | |
xrefs.append(xref) | |
if len(xrefs) != 1: | |
print(hex(ea), "%d xrefs" % len(xrefs)) | |
if len(xrefs) == 0: | |
return None | |
one_worked = False | |
for xref in xrefs: | |
if GetMnem(xref) != "mov": | |
print(hex(ea), hex(xref), "not a mov") | |
continue | |
if GetOpType(xref, 0) != MEM_REF: | |
print(hex(ea), hex(xref), "not correct op type (0)") | |
continue | |
if GetOpType(xref, 1) != GEN_REG: | |
print(hex(ea), hex(xref), "not correct op type (1)") | |
continue | |
p1 = PrevHead(xref) | |
if GetMnem(p1) != "movzx": | |
print(hex(ea), hex(p1), "not a movzx") | |
continue | |
if GetOpType(p1, 0) != GEN_REG: | |
print(hex(ea), hex(p1), "not correct op type (0)") | |
continue | |
if GetOpType(p1, 1) != BASE_INDEX: | |
print(hex(ea), hex(p1), "not correct op type (1)") | |
continue | |
p2 = PrevHead(p1) | |
if GetMnem(p2) != "mov": | |
print(hex(ea), hex(p2), "not a mov") | |
continue | |
if GetOpType(p2, 0) != GEN_REG: | |
print(hex(ea), hex(p2), "not correct op type (0)") | |
continue | |
if GetOpType(p2, 1) != BASE_INDEX_DISP: | |
print(hex(ea), hex(p2), "not correct op type (1)") | |
continue | |
p3 = PrevHead(p2) | |
if GetMnem(p3) != "mov": | |
print(hex(ea), hex(p3), "not a mov") | |
continue | |
if GetOpType(p3, 0) != BASE_INDEX_DISP: | |
print(hex(ea), hex(p3), "not correct op type (0)") | |
continue | |
if GetOpType(p3, 1) != IMMED: | |
print(hex(ea), hex(p3), "not correct op type (1)") | |
continue | |
string_ea = GetOperandValue(p3, 1) | |
return GetManyBytes(string_ea, 1) | |
return None | |
def main(): | |
ea = 0x729900 | |
ret = "" | |
while True: | |
c = doone(ea) | |
if c is None: | |
break | |
print(chr(ord(c)), hex(ord(c))) | |
ret += c | |
ea += 0x1 | |
print(ret) | |
if __name__ == "__main__": | |
main() | |
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