在 Assembly 中使用 /dev/urandom 生成 256 个数字；
Generate 256 numbers using /dev/urandom in Assembly;
我想知道如何使用 /dev/urandom 生成 32 位汇编数字。
我知道我应该在内存中有文件名“/dev/urandom”：
segment.data :
file : db "/dev/random",10
len : equ $-file
index : db "1",10
lenindex : equ $-index
然后我应该在我的循环中读取文件以生成一个数字并在生成的数字的索引中写入 1，这是我的循环
loop1 : xor ecx,ecx
cmp ecx,256
je end_loop1
mov EAX, 5
mov ebx, file
mov ecx, 0; o for octal // I guess this is how i generate a number (by reading it)
mov edx, 0001o;o for octal // Permission on file.
inc ecx
int 0x80;
mov ebx,eax
mov eax,4
mov ecx,index
mov edx,lenindex
int 0x80
jmp loop1
你可能是 constat，我是 32 位汇编的初学者，如果有人解释我如何使用 /dev/urandom 生成数字并在生成的数字的索引中指示 1，我会很高兴。
一次获取 256 个随机字节并打印它们（NASM 汇编程序）：
SECTION .data ; Section containing initialised data
file db "/dev/urandom",0
txt db " random bytes generated", 0x0A, 0x0A
txt_len EQU $ - txt
index dd 0
SECTION .bss ; Section containing uninitialised data
decstr resb 40 ; 40 Bytes for an ASCII string
decstr_len resd 1
filedescriptor resd 1
numbers resb 256
SECTION .text ; Section containing code
global _start ; Linker needs this to find the entry point!
_start:
; http://www.lxhp.in-berlin.de/lhpsysc1.html#open
mov eax, 5 ; SYSCALL open
mov ebx, file ; File descriptor
mov ecx, 0 ; Access: read only
mov edx, 0x00004 ; Mode: read by others
int 0x80 ; Call Linux kernel
mov [filedescriptor], eax ; Store the resulting fd
; http://www.lxhp.in-berlin.de/lhpsysc1.html#read
mov eax, 3 ; SYSCALL read
mov ebx, [filedescriptor] ; File descriptor
mov ecx, numbers ; Pointer to input buffer
mov edx, 256 ; Max. count of bytes to read
int 0x80 ; Call Linux kernel
mov [index], eax ; Store the count of bytes received
; http://www.lxhp.in-berlin.de/lhpsysc1.html#close
mov eax, 6 ; SYSCALL close
mov ebx, [filedescriptor] ; File descriptor
int 0x80 ; Call Linux kernel
; Print index
mov eax, [index] ; Argument: Integer to convert
mov edi, decstr ; Argument: Address of the target string
call int2str ; Get the digits of EAX and store it as ASCII & LF & NUL
sub edi, decstr ; EDI (pointer to the terminating NULL) - pointer to decstr = length of the string
dec edi ; Shorten the string by the LF
mov [decstr_len], edi ; Store the resulting length of the string
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, decstr ; Pointer to output buffer
mov edx, [decstr_len] ; count of bytes to send
int 0x80
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, txt ; Pointer to output buffer
mov edx, txt_len ; count of bytes to send
int 0x80
; Print the numbers
mov esi, numbers ; Start address for lodsb
L1: ; Loop to print <index> numbers
xor eax, eax ; Argument: Integer to convert
lodsb
mov edi, decstr ; Argument: Address of the target string
call int2str ; Get the digits of EAX and store it as ASCII & LF & NUL
sub edi, decstr ; EDI (pointer to the terminating NULL) - pointer to decstr = length of the string
mov [decstr_len], edi ; Store the resulting length of the string
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, decstr ; Pointer to output buffer
mov edx, [decstr_len] ; count of bytes to send
int 0x80
sub dword [index], 1
jnz L1 ; Do it again
; http://www.lxhp.in-berlin.de/lhpsysc1.html#exit
mov eax, 1 ; SYSCALL exit
mov ebx, 0 ; Exit Code
int 80h ; Call Linux kernel
int2str: ; Converts an positive integer in EAX to a string pointed to by EDI
xor ecx, ecx
mov ebx, 10
.LL1: ; First loop: Collect the remainders
xor edx, edx ; Clear EDX for div
div ebx ; EDX:EAX/EBX -> EAX Remainder EDX
push dx ; Save remainder
inc ecx ; Increment push counter
test eax, eax ; Anything left to divide?
jnz .LL1 ; Yes: loop once more
.LL2: ; Second loop: Retrieve the remainders
pop dx ; In DL is the value
or dl, '0' ; To ASCII
mov [edi], dl ; Save it to the string
inc edi ; Increment the pointer to the string
loop .LL2 ; Loop ECX times
mov word [edi], 0x0A ; Last characters: LF, NUL
inc edi
ret ; RET: EDI points to the terminating NULL
要一一获取 256 个随机 DWORD 并一一打印（NASM 汇编程序）：
SECTION .data ; Section containing initialised data
file db "/dev/urandom",0 ; NUL terminated (ASCIZ)!
loopcount dd 256
SECTION .bss ; Section containing uninitialised data
decstr resb 40 ; 40 Bytes for an ASCII string
decstr_len resd 1
filedescriptor resd 1
number resd 1
SECTION .text ; Section containing code
global _start ; Linker needs this to find the entry point!
_start:
; http://www.lxhp.in-berlin.de/lhpsysc1.html#open
mov eax, 5 ; SYSCALL open
mov ebx, file ; File descriptor
mov ecx, 0 ; Access: read only
mov edx, 0x00004 ; Mode: read by others
int 0x80 ; Call Linux kernel
mov [filedescriptor], eax ; Store the resulting fd
L1: ; Loop to print <loopcount> numbers
; http://www.lxhp.in-berlin.de/lhpsysc1.html#read
mov eax, 3 ; SYSCALL read
mov ebx, [filedescriptor] ; File descriptor
mov ecx, number ; Pointer to input buffer
mov edx, 4 ; Max. count of bytes to read
int 0x80 ; Call Linux kernel
; Print the number
mov eax, [number] ; Argument: Integer to convert
mov edi, decstr ; Argument: Address of the target string
call int2str ; Get the digits of EAX and store it as ASCII & LF & NUL
sub edi, decstr ; EDI (pointer to the terminating NULL) - pointer to decstr = length of the string
mov [decstr_len], edi ; Store the resulting length of the string
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, decstr ; Pointer to output buffer
mov edx, [decstr_len] ; count of bytes to send
int 0x80
sub dword [loopcount], 1
jnz L1 ; Do it again
; http://www.lxhp.in-berlin.de/lhpsysc1.html#close
mov eax, 6 ; SYSCALL close
mov ebx, [filedescriptor] ; File descriptor
int 0x80 ; Call Linux kernel
; http://www.lxhp.in-berlin.de/lhpsysc1.html#exit
mov eax, 1 ; SYSCALL exit
mov ebx, 0 ; Exit Code
int 80h ; Call Linux kernel
int2str: ; Converts an positive integer in EAX to a string pointed to by EDI
xor ecx, ecx
mov ebx, 10
.LL1: ; First loop: Collect the remainders
xor edx, edx ; Clear EDX for div
div ebx ; EDX:EAX/EBX -> EAX Remainder EDX
push dx ; Save remainder
inc ecx ; Increment push counter
test eax, eax ; Anything left to divide?
jnz .LL1 ; Yes: loop once more
.LL2: ; Second loop: Retrieve the remainders
pop dx ; In DL is the value
or dl, '0' ; To ASCII
mov [edi], dl ; Save it to the string
inc edi ; Increment the pointer to the string
loop .LL2 ; Loop ECX times
mov word [edi], 0x0A ; Last characters: LF, NUL
inc edi
ret ; RET: EDI points to the terminating NULL
您可以更改
中的号码
mov edx, 4 ; Max. count of bytes to read
获取另一个范围，例如
mov edx, 2 ; Max. count of bytes to read
对于 WORD 范围 (0..65535)。
我想知道如何使用 /dev/urandom 生成 32 位汇编数字。 我知道我应该在内存中有文件名“/dev/urandom”：
segment.data :
file : db "/dev/random",10
len : equ $-file
index : db "1",10
lenindex : equ $-index
然后我应该在我的循环中读取文件以生成一个数字并在生成的数字的索引中写入 1，这是我的循环
loop1 : xor ecx,ecx
cmp ecx,256
je end_loop1
mov EAX, 5
mov ebx, file
mov ecx, 0; o for octal // I guess this is how i generate a number (by reading it)
mov edx, 0001o;o for octal // Permission on file.
inc ecx
int 0x80;
mov ebx,eax
mov eax,4
mov ecx,index
mov edx,lenindex
int 0x80
jmp loop1
你可能是 constat，我是 32 位汇编的初学者，如果有人解释我如何使用 /dev/urandom 生成数字并在生成的数字的索引中指示 1，我会很高兴。
一次获取 256 个随机字节并打印它们（NASM 汇编程序）：
SECTION .data ; Section containing initialised data
file db "/dev/urandom",0
txt db " random bytes generated", 0x0A, 0x0A
txt_len EQU $ - txt
index dd 0
SECTION .bss ; Section containing uninitialised data
decstr resb 40 ; 40 Bytes for an ASCII string
decstr_len resd 1
filedescriptor resd 1
numbers resb 256
SECTION .text ; Section containing code
global _start ; Linker needs this to find the entry point!
_start:
; http://www.lxhp.in-berlin.de/lhpsysc1.html#open
mov eax, 5 ; SYSCALL open
mov ebx, file ; File descriptor
mov ecx, 0 ; Access: read only
mov edx, 0x00004 ; Mode: read by others
int 0x80 ; Call Linux kernel
mov [filedescriptor], eax ; Store the resulting fd
; http://www.lxhp.in-berlin.de/lhpsysc1.html#read
mov eax, 3 ; SYSCALL read
mov ebx, [filedescriptor] ; File descriptor
mov ecx, numbers ; Pointer to input buffer
mov edx, 256 ; Max. count of bytes to read
int 0x80 ; Call Linux kernel
mov [index], eax ; Store the count of bytes received
; http://www.lxhp.in-berlin.de/lhpsysc1.html#close
mov eax, 6 ; SYSCALL close
mov ebx, [filedescriptor] ; File descriptor
int 0x80 ; Call Linux kernel
; Print index
mov eax, [index] ; Argument: Integer to convert
mov edi, decstr ; Argument: Address of the target string
call int2str ; Get the digits of EAX and store it as ASCII & LF & NUL
sub edi, decstr ; EDI (pointer to the terminating NULL) - pointer to decstr = length of the string
dec edi ; Shorten the string by the LF
mov [decstr_len], edi ; Store the resulting length of the string
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, decstr ; Pointer to output buffer
mov edx, [decstr_len] ; count of bytes to send
int 0x80
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, txt ; Pointer to output buffer
mov edx, txt_len ; count of bytes to send
int 0x80
; Print the numbers
mov esi, numbers ; Start address for lodsb
L1: ; Loop to print <index> numbers
xor eax, eax ; Argument: Integer to convert
lodsb
mov edi, decstr ; Argument: Address of the target string
call int2str ; Get the digits of EAX and store it as ASCII & LF & NUL
sub edi, decstr ; EDI (pointer to the terminating NULL) - pointer to decstr = length of the string
mov [decstr_len], edi ; Store the resulting length of the string
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, decstr ; Pointer to output buffer
mov edx, [decstr_len] ; count of bytes to send
int 0x80
sub dword [index], 1
jnz L1 ; Do it again
; http://www.lxhp.in-berlin.de/lhpsysc1.html#exit
mov eax, 1 ; SYSCALL exit
mov ebx, 0 ; Exit Code
int 80h ; Call Linux kernel
int2str: ; Converts an positive integer in EAX to a string pointed to by EDI
xor ecx, ecx
mov ebx, 10
.LL1: ; First loop: Collect the remainders
xor edx, edx ; Clear EDX for div
div ebx ; EDX:EAX/EBX -> EAX Remainder EDX
push dx ; Save remainder
inc ecx ; Increment push counter
test eax, eax ; Anything left to divide?
jnz .LL1 ; Yes: loop once more
.LL2: ; Second loop: Retrieve the remainders
pop dx ; In DL is the value
or dl, '0' ; To ASCII
mov [edi], dl ; Save it to the string
inc edi ; Increment the pointer to the string
loop .LL2 ; Loop ECX times
mov word [edi], 0x0A ; Last characters: LF, NUL
inc edi
ret ; RET: EDI points to the terminating NULL
要一一获取 256 个随机 DWORD 并一一打印（NASM 汇编程序）：
SECTION .data ; Section containing initialised data
file db "/dev/urandom",0 ; NUL terminated (ASCIZ)!
loopcount dd 256
SECTION .bss ; Section containing uninitialised data
decstr resb 40 ; 40 Bytes for an ASCII string
decstr_len resd 1
filedescriptor resd 1
number resd 1
SECTION .text ; Section containing code
global _start ; Linker needs this to find the entry point!
_start:
; http://www.lxhp.in-berlin.de/lhpsysc1.html#open
mov eax, 5 ; SYSCALL open
mov ebx, file ; File descriptor
mov ecx, 0 ; Access: read only
mov edx, 0x00004 ; Mode: read by others
int 0x80 ; Call Linux kernel
mov [filedescriptor], eax ; Store the resulting fd
L1: ; Loop to print <loopcount> numbers
; http://www.lxhp.in-berlin.de/lhpsysc1.html#read
mov eax, 3 ; SYSCALL read
mov ebx, [filedescriptor] ; File descriptor
mov ecx, number ; Pointer to input buffer
mov edx, 4 ; Max. count of bytes to read
int 0x80 ; Call Linux kernel
; Print the number
mov eax, [number] ; Argument: Integer to convert
mov edi, decstr ; Argument: Address of the target string
call int2str ; Get the digits of EAX and store it as ASCII & LF & NUL
sub edi, decstr ; EDI (pointer to the terminating NULL) - pointer to decstr = length of the string
mov [decstr_len], edi ; Store the resulting length of the string
; http://www.lxhp.in-berlin.de/lhpsysc1.html#write
mov eax, 4 ; SYSCALL write
mov ebx, 1 ; File descriptor: STDOUT
mov ecx, decstr ; Pointer to output buffer
mov edx, [decstr_len] ; count of bytes to send
int 0x80
sub dword [loopcount], 1
jnz L1 ; Do it again
; http://www.lxhp.in-berlin.de/lhpsysc1.html#close
mov eax, 6 ; SYSCALL close
mov ebx, [filedescriptor] ; File descriptor
int 0x80 ; Call Linux kernel
; http://www.lxhp.in-berlin.de/lhpsysc1.html#exit
mov eax, 1 ; SYSCALL exit
mov ebx, 0 ; Exit Code
int 80h ; Call Linux kernel
int2str: ; Converts an positive integer in EAX to a string pointed to by EDI
xor ecx, ecx
mov ebx, 10
.LL1: ; First loop: Collect the remainders
xor edx, edx ; Clear EDX for div
div ebx ; EDX:EAX/EBX -> EAX Remainder EDX
push dx ; Save remainder
inc ecx ; Increment push counter
test eax, eax ; Anything left to divide?
jnz .LL1 ; Yes: loop once more
.LL2: ; Second loop: Retrieve the remainders
pop dx ; In DL is the value
or dl, '0' ; To ASCII
mov [edi], dl ; Save it to the string
inc edi ; Increment the pointer to the string
loop .LL2 ; Loop ECX times
mov word [edi], 0x0A ; Last characters: LF, NUL
inc edi
ret ; RET: EDI points to the terminating NULL
您可以更改
中的号码mov edx, 4 ; Max. count of bytes to read
获取另一个范围，例如
mov edx, 2 ; Max. count of bytes to read
对于 WORD 范围 (0..65535)。