mirror of
https://github.com/cea-sec/miasm
synced 2026-06-21 13:48:18 +00:00
Fabrice Desclaux
83 lines
1.9 KiB
Python
83 lines
1.9 KiB
Python
#! /usr/bin/env python
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from miasm2.core.cpu import parse_ast
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from miasm2.arch.arm.arch import mn_arm, base_expr, variable
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from miasm2.core import parse_asm
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from miasm2.expression.expression import *
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from miasm2.core import asmbloc
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from elfesteem.strpatchwork import StrPatchwork
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my_mn = mn_arm
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reg_and_id = dict(mn_arm.regs.all_regs_ids_byname)
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def my_ast_int2expr(a):
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return ExprInt32(a)
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def my_ast_id2expr(t):
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return reg_and_id.get(t, ExprId(t, size=32))
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my_var_parser = parse_ast(my_ast_id2expr, my_ast_int2expr)
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base_expr.setParseAction(my_var_parser)
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txt = '''
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main:
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STMFD SP!, {R4, R5, LR}
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MOV R0, mystr & 0xffff
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ORR R0, R0, mystr & 0xffff0000
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MOV R4, R0
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MOV R1, mystrend & 0xffff
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ORR R1, R1, mystrend & 0xffff0000
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xxx:
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LDRB R2, [PC, key-$]
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loop:
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LDRB R3, [R0]
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EOR R3, R3, R2
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STRB R3, [R0], 1
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CMP R0, R1
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BNE loop
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end:
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MOV R0, R4
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LDMFD SP!, {R4, R5, PC}
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key:
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.byte 0x11
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mystr:
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.string "test string"
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mystrend:
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.long 0
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'''
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blocs_b, symbol_pool_b = parse_asm.parse_txt(my_mn, "b", txt)
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blocs_l, symbol_pool_l = parse_asm.parse_txt(my_mn, "l", txt)
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# fix shellcode addr
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symbol_pool_b.set_offset(symbol_pool_b.getby_name("main"), 0x0)
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symbol_pool_l.set_offset(symbol_pool_l.getby_name("main"), 0x0)
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# graph sc####
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g = asmbloc.bloc2graph(blocs_l[0])
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open("graph.txt", "w").write(g)
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s_b = StrPatchwork()
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s_l = StrPatchwork()
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print "symbols"
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print symbol_pool_l
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# dont erase from start to shell code padading
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resolved_b, patches_b = asmbloc.asm_resolve_final(
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my_mn, blocs_b[0], symbol_pool_b)
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resolved_l, patches_l = asmbloc.asm_resolve_final(
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my_mn, blocs_l[0], symbol_pool_l)
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print patches_b
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for offset, raw in patches_b.items():
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s_b[offset] = raw
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for offset, raw in patches_l.items():
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s_l[offset] = raw
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open('demo_arm_b.bin', 'w').write(str(s_b))
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open('demo_arm_l.bin', 'w').write(str(s_l))
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