c002.S

.section .rodata
msg_enter_pwd:
	.string "Enter password: "
msg_pwd_wrong:
	.string "Sorry, wrong password!"
msg_pwd_ok:
	.string "\nPassword OK!"
msg_fmt_flag:
	.string "Congratulations, you solved it!\nThe flag is: %s\n"


.section .data
encrypted_pwd:
	.byte 0x32, 0x6a, 0xf, 0x6, 0x6a, 0x74, 0x27, 0x37, 0x2d, 0x24, 0xb, 0x14, 0x11, 0x2c, 0x11, 0x75, 0x3f, 0x28, 0x2e, 0x72, 0x3, 0x7c, 0x2e, 0x17, 0x1f, 0x7d, 0x71, 0x7c, 0x13, 0x8, 0x28, 0x23, 0x22, 0x12, 0x35, 0x24, 0x3, 0x2d, 0xf, 0x15, 0x74, 0x7d, 0x2d, 0x20, 0x3f, 0x7d, 0x36, 0x37, 0x31, 0x76, 0x2e, 0x24, 0x28, 0x1, 0x9, 0xd, 0x34, 0x3, 0x1f, 0x6e, 0x6a, 0x2a, 0x73, 0xf, 0x75, 0x36, 0xd, 0x2a, 0x10
encrypted_pwd_end:

encrypted_flag:
	.byte 0x30, 0x61, 0x1f, 0x14, 0x6a, 0x74, 0x20, 0x9, 0xe, 0x3, 0x7f, 0x34, 0x32, 0x5b, 0x64, 0x7, 0x42, 0xb, 0x5b, 0x56, 0x25, 0x5a, 0x5c, 0x6a, 0x6e, 0xa, 0x57, 0x1, 0x34, 0x78, 0xb, 0x5f, 0x5e, 0x63, 0x43, 0x58, 0x77, 0xd, 0x2c, 0x64, 0x6, 0xa, 0x50, 0x3, 0x49, 0x5e, 0x47, 0x47, 0x47, 0xb, 0xf, 0x55, 0xc, 0x76, 0x78, 0x2a, 0x44, 0x25, 0x3f, 0x1f, 0x19, 0x9, 0x1, 0x2f, 0x9, 0x41, 0x7c, 0x57, 0x28
encrypted_flag_end:

padding:
	.long 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0


.section .text
	.global main
	.extern printf
	.extern puts
	.extern fgets
	.extern stdin
main:
	pushq	%rbp
	movq	%rsp, %rbp
	subq	$(16 * 100), %rsp

	leaq	msg_enter_pwd(%rip), %rdi
	xorl	%eax, %eax
	call	printf

	xorl	%eax, %eax
	leaq	-200(%rbp), %rdi
	movl	$25, %ecx
	rep stosq

	leaq	-200(%rbp), %rdi
	movl	$200, %esi
	movq	stdin(%rip), %rdx
	callq	fgets

	leaq	-200(%rbp), %rdi
	callq	handle_pwd
	testb	%al, %al
	jz	1f
	leaq	msg_pwd_ok(%rip), %rdi
	callq	puts
	leaq	msg_fmt_flag(%rip), %rdi
	leaq	encrypted_flag(%rip), %rsi
	xorl	%eax, %eax
	callq	printf
	jmp	2f
1:
	leaq	msg_pwd_wrong(%rip), %rdi
	callq	puts
2:
	xorl	%eax, %eax
	movq	%rbp, %rsp
	popq	%rbp
	retq

handle_pwd:
	pushq	%rbp
	movq	%rsp, %rbp
	subq	$32, %rsp
	movq	%rdi, -8(%rbp)
	callq	strlen
	movq	%rax, -16(%rbp)
	movq	-8(%rbp), %rdi
	cmpb	$'\n', -1(%rdi, %rax)
	jne	2f
	movb	$0, -1(%rdi, %rax)
	decq	%rax
2:
	movq	%rax, -24(%rbp)
	movq	%rax, %rcx
	leaq	encrypted_pwd(%rip), %rdx
1:
	xorb	%al, -1(%rdx, %rcx)
	decq	%rcx
	jnz	1b
	movq	-24(%rbp), %rcx
	movq	-8(%rbp), %rdi
	leaq	encrypted_pwd(%rip), %rdx
	leaq	encrypted_flag(%rip), %rsi
3:
	movb	-1(%rdi, %rcx), %al
	cmpb	-1(%rdx, %rcx), %al
	jne	.Lret_wrong
	xorb	%al, -1(%rsi, %rcx)
	decq	%rcx
	jnz	3b
	movl	$1, %eax
	jmp	.Lret
.Lret_wrong:
	xorl	%eax, %eax
.Lret:
	movq	%rbp, %rsp
	popq	%rbp
	retq