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09/21/2009 at 09:30PM PDT, ID: 24750525 | Points: 500
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Binary Bomb Lab - Last Phase

Asked by Dvcs in Assembly Programming Language

Tags: assembly

Hi, I'm working on a puzzle called a bomb lab to learn assembly language. I was going OK then stuck at this very last phase.

So far, I've figured out that this phase takes 6 decimal arguments and then swaps its order.
e.g) 1 2 3 4 5 6 -> 6 5 4 3 2 1

However, after this swapping process, the code threw me off (specifically speaking, from 0x401234). I sense that it's a linked list... but somehow I am lost.

Could you explain me what's going on with this code? And, answer as well. This is a good stuff, but I don't want to spend too much time on this...

Here is the code. Thanks in advance. 
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0x00000000004011b1 <phase_6+0>:	push   %r13
0x00000000004011b3 <phase_6+2>:	push   %r12
0x00000000004011b5 <phase_6+4>:	push   %rbp
0x00000000004011b6 <phase_6+5>:	push   %rbx
0x00000000004011b7 <phase_6+6>:	sub    $0x58,%rsp
0x00000000004011bb <phase_6+10>:	mov    $0x503af0,%r13d
0x00000000004011c1 <phase_6+16>:	lea    0x30(%rsp),%rsi
0x00000000004011c6 <phase_6+21>:	callq  0x4013c1 <read_six_numbers>
0x00000000004011cb <phase_6+26>:	mov    $0x0,%r12d
0x00000000004011d1 <phase_6+32>:	movslq %r12d,%rax
0x00000000004011d4 <phase_6+35>:	mov    0x30(%rsp,%rax,4),%eax
0x00000000004011d8 <phase_6+39>:	dec    %eax
0x00000000004011da <phase_6+41>:	cmp    $0x5,%eax
0x00000000004011dd <phase_6+44>:	jbe    0x4011e4 <phase_6+51>
0x00000000004011df <phase_6+46>:	callq  0x4017e5 <explode_bomb>
0x00000000004011e4 <phase_6+51>:	lea    0x1(%r12),%ebx
0x00000000004011e9 <phase_6+56>:	cmp    $0x5,%ebx
0x00000000004011ec <phase_6+59>:	jg     0x40120a <phase_6+89>
0x00000000004011ee <phase_6+61>:	movslq %r12d,%rbp
0x00000000004011f1 <phase_6+64>:	movslq %ebx,%rdx
0x00000000004011f4 <phase_6+67>:	mov    0x30(%rsp,%rbp,4),%eax
0x00000000004011f8 <phase_6+71>:	cmp    0x30(%rsp,%rdx,4),%eax
0x00000000004011fc <phase_6+75>:	jne    0x401203 <phase_6+82>
0x00000000004011fe <phase_6+77>:	callq  0x4017e5 <explode_bomb>
0x0000000000401203 <phase_6+82>:	inc    %ebx
0x0000000000401205 <phase_6+84>:	cmp    $0x5,%ebx
0x0000000000401208 <phase_6+87>:	jle    0x4011f1 <phase_6+64>
0x000000000040120a <phase_6+89>:	inc    %r12d
0x000000000040120d <phase_6+92>:	cmp    $0x5,%r12d
0x0000000000401211 <phase_6+96>:	jle    0x4011d1 <phase_6+32>
0x0000000000401213 <phase_6+98>:	mov    $0x0,%r12d
0x0000000000401219 <phase_6+104>:	mov    $0x7,%ecx
0x000000000040121e <phase_6+109>:	movslq %r12d,%rdx
0x0000000000401221 <phase_6+112>:	mov    %ecx,%eax
0x0000000000401223 <phase_6+114>:	sub    0x30(%rsp,%rdx,4),%eax
0x0000000000401227 <phase_6+118>:	mov    %eax,0x30(%rsp,%rdx,4)
0x000000000040122b <phase_6+122>:	inc    %r12d
0x000000000040122e <phase_6+125>:	cmp    $0x5,%r12d
0x0000000000401232 <phase_6+129>:	jle    0x40121e <phase_6+109>
0x0000000000401234 <phase_6+131>:	mov    $0x0,%r12d
0x000000000040123a <phase_6+137>:	mov    %r13,%rbp
0x000000000040123d <phase_6+140>:	mov    $0x1,%ebx
0x0000000000401242 <phase_6+145>:	movslq %r12d,%rax
0x0000000000401245 <phase_6+148>:	cmpl   $0x1,0x30(%rsp,%rax,4)
0x000000000040124a <phase_6+153>:	jle    0x40125a <phase_6+169>
0x000000000040124c <phase_6+155>:	mov    0x30(%rsp,%rax,4),%eax
0x0000000000401250 <phase_6+159>:	mov    0x8(%rbp),%rbp
0x0000000000401254 <phase_6+163>:	inc    %ebx
0x0000000000401256 <phase_6+165>:	cmp    %ebx,%eax
0x0000000000401258 <phase_6+167>:	jg     0x401250 <phase_6+159>
0x000000000040125a <phase_6+169>:	movslq %r12d,%rax
0x000000000040125d <phase_6+172>:	mov    %rbp,(%rsp,%rax,8)
0x0000000000401261 <phase_6+176>:	inc    %r12d
0x0000000000401264 <phase_6+179>:	cmp    $0x5,%r12d
0x0000000000401268 <phase_6+183>:	jle    0x40123a <phase_6+137>
0x000000000040126a <phase_6+185>:	mov    (%rsp),%rbp
0x000000000040126e <phase_6+189>:	mov    %rbp,%r13
0x0000000000401271 <phase_6+192>:	mov    $0x1,%r12d
0x0000000000401277 <phase_6+198>:	movslq %r12d,%rax
0x000000000040127a <phase_6+201>:	mov    (%rsp,%rax,8),%rax
0x000000000040127e <phase_6+205>:	mov    %rax,0x8(%rbp)
0x0000000000401282 <phase_6+209>:	mov    %rax,%rbp
0x0000000000401285 <phase_6+212>:	inc    %r12d
0x0000000000401288 <phase_6+215>:	cmp    $0x5,%r12d
0x000000000040128c <phase_6+219>:	jle    0x401277 <phase_6+198>
0x000000000040128e <phase_6+221>:	movq   $0x0,0x8(%rax)
0x0000000000401296 <phase_6+229>:	mov    %r13,%rbp
0x0000000000401299 <phase_6+232>:	mov    $0x0,%r12d
0x000000000040129f <phase_6+238>:	mov    0x8(%rbp),%rdx
0x00000000004012a3 <phase_6+242>:	mov    0x0(%rbp),%eax
0x00000000004012a6 <phase_6+245>:	cmp    (%rdx),%eax
0x00000000004012a8 <phase_6+247>:	jge    0x4012af <phase_6+254>
0x00000000004012aa <phase_6+249>:	callq  0x4017e5 <explode_bomb>
0x00000000004012af <phase_6+254>:	mov    0x8(%rbp),%rbp
0x00000000004012b3 <phase_6+258>:	inc    %r12d
0x00000000004012b6 <phase_6+261>:	cmp    $0x4,%r12d
0x00000000004012ba <phase_6+265>:	jle    0x40129f <phase_6+238>
0x00000000004012bc <phase_6+267>:	add    $0x58,%rsp
0x00000000004012c0 <phase_6+271>:	pop    %rbx
0x00000000004012c1 <phase_6+272>:	pop    %rbp
0x00000000004012c2 <phase_6+273>:	pop    %r12
0x00000000004012c4 <phase_6+275>:	pop    %r13
0x00000000004012c6 <phase_6+277>:	retq
 
Keywords: Binary Bomb Lab - Last Phase
Title
1 outlook mso.dll, outcmd.dat file cor…
2 Pain in the diodes...
 
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[+][-]09/22/09 12:47 AM, ID: 25390387

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