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linux

Today I will show you how to use the MMX instructions. SSE stands for Streaming SIMD Extensions and uses 128-bit registers: XMM0 XMM1 XMM2 XMM3 XMM4 XMM5 XMM6 XMM7 The capabilities of the XMM registers are: 2 64-bit floating points (double precision) 2 64-bit integers 4 32-bit floating points (single-precision)… Continue Reading Programming with FASM – divide / multiply in Linux – part 009 .

I haven’t worked with FASM, Linux, and system functions for a while. Here is an extremely simple example for beginners with output on my nickname: mythcat.

Assembly (x86)
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format ELF executable 3
entry start
 
segment readable executable
 
BYTES = 255  ;number of byte 255
 
start:
 
;read a char from input
char_read:
  mov eax,3
  mov ebx,0  ;0 stdin, 1 stdout, 2 stderr
  mov ecx,char_Buffer
  mov edx,BYTES
  int 0x80
 
;write byte read to output
char_write:
  mov eax,4
  mov ebx,1
  mov ecx,char_Buffer
  mov dl,[CharRead]
  int 0x80
 
  jmp char_read
 
;exit from program
exit:
  mov eax,1  ;  System call 'exit'
  xor ebx,ebx  ;  'xor ebx,ebx'
  int 0x80
 
segment readable writeable
 
  char_Buffer db BYTES dup(0)
  CharRead db 1

The result is … as follows:

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[mythcat@desk fasm]$ ./fasm char_write.asm
flat assembler  version 1.73.24  (16384 kilobytes memory)
3 passes, 428 bytes.
[mythcat@desk fasm]$ ./char_write
m
my
yt
th
hc
ca
at
t^C

The tutorial for today is about debugging and FASM with fdbg tool. For debugging and testing you can use any debugger, but you can use the You can here all version for these operating system: GUI for Windows x64, Windows x64, Linux x64 and UEFI x64. I used the Linux… Continue Reading Programming with FASM – the format ELF executable – part 007 .

You need a USB stick to put the Windows 10 from the official website image with a size of 5.4 Gb.

Shell
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# woeusb -v --device  Win10_1909_English_x64.iso /dev/sdc --target-filesystem NTFS
trap_return: INFO: returning from process_commandline_parameters
WoeUSB v3.3.1
==============================
determine_target_parameters: Info: Target device is '/dev/sdc'.
determine_target_parameters: Info: Target partition is '/dev/sdc1'.
Mounting source filesystem...
Wiping all existing partition table and filesystem signatures in /dev/sdc...
/dev/sdc: 2 bytes were erased at offset 0x000001fe (dos): 55 aa
/dev/sdc: calling ioctl to re-read partition table: Success
Ensure that /dev/sdc is really wiped...
Creating new partition table on /dev/sdc...
Creating target partition...
Making system realize that partition table has changed...
Wait 3 seconds for block device nodes to populate...
Cluster size has been automatically set to 4096 bytes.
Creating NTFS volume structures.
mkntfs completed successfully. Have a nice day.
--2020-04-02 23:04:52--  https://github.com/pbatard/rufus/raw/master/res/uefi/uefi-ntfs.img
Resolving github.com (github.com)... 140.82.118.4
Connecting to github.com (github.com)|140.82.118.4|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://raw.githubusercontent.com/pbatard/rufus/master/res/uefi/uefi-ntfs.img [following]
--2020-04-02 23:04:52--  https://raw.githubusercontent.com/pbatard/rufus/master/res/uefi/uefi-ntfs.img
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 151.101.112.133
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|151.101.112.133|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 524288 (512K) [application/octet-stream]
Saving to: ‘/tmp/WoeUSB.o2ZmsU.tempdir/uefi-ntfs.img’
 
uefi-ntfs.img       100%[===================>] 512,00K  1,56MB/s    in 0,3s    
 
2020-04-02 23:04:53 (1,56 MB/s) - ‘/tmp/WoeUSB.o2ZmsU.tempdir/uefi-ntfs.img’ saved [524288/524288]
 
1024+0 records in
1024+0 records out
524288 bytes (524 kB, 512 KiB) copied, 0,214865 s, 2,4 MB/s
Mounting target filesystem...
Applying workaround to prevent 64-bit systems with big primary memory from being unresponsive during copying files.
Copying files from source media...
...
INFO: Copying "./sources/imagingprovider.dll"...
11%
INFO: Copying "./sources/inf/setup.cfg"...
11%
INFO: Copying "./sources/input.dll"...
11%
INFO: Copying "./sources/install.wim"...
11%
...
INFO: Copying "./support/logging/winsetupetw.dll"...
Installing GRUB bootloader for legacy PC booting support...
Installing for i386-pc platform.
...
Warning: command "echo 0 > /proc/sys/vm/dirty_bytes" - returned code  $?
Unmounting and removing "/media/woeusb_source_1585857878_9470"...
Unmounting and removing "/media/woeusb_target_1585857878_9470"...
You may now safely detach the target device
Done :)
The target device should be bootable now

Reboot with the USB stick with the boot set on USB Device and you can install the Windows 10.

I used Android Studion 3.6.1 on Ubuntu Linux. I start an Empty Project and I change the activity_main.xml file into this:

XHTML
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<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/gradient_background"
    tools:context=".MainActivity">
 
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="GRADIENT COLORS"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
 
</androidx.constraintlayout.widget.ConstraintLayout>

You can see I change the Hello Word! text into GRADIENT COLORS. I add this source line of code:

XHTML
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android:background="@drawable/gradient_background"

I create this resource XML into res –… Continue Reading Android Studio – simple gradient example.

I don’t like the Pug very much but for today I will write a simple intro tutorial. The Pug is a template engine for Node and for the browser which can make you more productive and your code more readable. It compiles to HTML and has a simplified syntax with… Continue Reading Pug: About the Pug javascript.

Let’s read from a text file named new_file.txt with an assembler program.

Assembly (x86)
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[mythcat@desk fasm]$ vim read_file.fasm
[mythcat@desk fasm]$ ./fasm.x64 read_file.fasm
flat assembler  version 1.73.16  (16384 kilobytes memory, x64)
2 passes, 261 bytes.
[mythcat@desk fasm]$ ./read_file
FASM : Hello, world![mythcat@desk fasm]$

The source code is easy to understand. This source code shows you how you can use a macro for print. The base of this source code use INT 0x80 with a rax register for many functions like… Continue Reading Programming with FASM – the format ELF executable – part 006 .

Let’s write into a text file named new_file.txt with an assembler program. First, you need to create this text file using the command touch.

Assembly (x86)
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[mythcat@desk fasm]$ vim write_file.fasm
[mythcat@desk fasm]$ ./fasm.x64 write_file.fasm
flat assembler  version 1.73.16  (16384 kilobytes memory, x64)
2 passes, 256 bytes.
[mythcat@desk fasm]$ touch new_file.txt
[mythcat@desk fasm]$ cat new_file.txt
[mythcat@desk fasm]$ ./write_file
[mythcat@desk fasm]$ cat new_file.txt
FASM : Hello, world!

The assembler FASM let us to write in the file using the INT 80 and some functions used with rax, rbx, rcx, rdx registers. For… Continue Reading Programming with FASM – the format ELF executable – part 005 .