Rating:
# Remote
After some googling we found that .sal file and SALEAE in each file inside can be opened in Logic 2.* program.
After trying all the algorithms in logic, we assume that this is some custom stuff. We can see that value in one channel in 1-4 and value in one channel in 5-8 is symmetrical. Now we can write this signal as 8 bits.
For example:
0100-0100;1000-0100; 0100-1000; etc;
Now we should parse it somehow. Logic offers export to the csv file function, which we will use.
So, the first symbol is 0100 - 0100. It does not look like ascii or smth, so we assume that this is the position on the keypad.
Now we assume that we have a keypad such as below (because why not?).
For example, 0100 - 0100 on the keypad it is 5. We get it like this:
Keypad:
xxxx
x*xx
xxxx
xxxx
The code on C# to get our passwords:
```C
using System;
using System.IO;
using System.Linq;
namespace ConsoleApp26
{
class Program
{
static void Main(string[] args)
{
bool SwapAxis = true;
bool InverseAxis = false;
using (var reader = new StreamReader(@"C:\\Users\\kukuxumushi\\Downloads\\Downloads\\hw_remote (1)\\csv.csv\\digital.csv"))
{
string keypad =
"123A" +
"456B" +
"789C" +
"*0#D";
reader.ReadLine();//skip headers
string prev_state = "";
while (!reader.EndOfStream)
{
string row = reader.ReadLine();
if (string.IsNullOrWhiteSpace(row))
continue;
//delete time
row = row.Substring(row.IndexOf(',') + 1);
//skip illegal states
if (row != "1,1,1,1,0,0,0,0" && (row.StartsWith("1,1,1,1,") || row.EndsWith(",0,0,0,0")))
continue;
//skip empty state
if (row == "1,1,1,1,0,0,0,0")
continue;
//skip multiple press states(jitter)
if (prev_state == row)
continue;
prev_state = row;
var nums = row.Split(',').Select(v => Convert.ToInt32(v)).ToArray();
int X = GetNum(nums, 0);//Get pos from first 4 channels
int Y = GetNum(nums, 1);//Get pos from second 4 channels
if (InverseAxis)
{
X = 3 - X;
Y = 3 - Y;
}
if (!SwapAxis)
Console.Write(keypad[X + Y * 4]);
else
Console.Write(keypad[Y + X * 4]);
}
}
}
static int GetNum(int[] ch, int pos)
{
if (pos != 0 && pos != 1)
throw new Exception();
if (pos == 0)
{
for (int i = 0; i < 4; i++)
if (ch[i] == 0)
return i;
}
else
{
for (int i = 0; i < 4; i++)
if (ch[4 + i] == 1)
return i;
}
throw new Exception();
}
}
}
```
Now we got 4 possible passwords:
1. 5424*D2B10*7286B*364742*DB1B4B7*#D
2. 5242AD401BA34680A782324AD010203ACD
3. 9C#CA1#7D3AB#687A08CBC#A17D7C7BA21
4. 9#C#*1C3D7*0C863*B6#0#C*13D3#30*41
4 passwords are because we don’t know from which side/angle we start.
Trying all the password one by one:
Looks like the flag is wrong.
HTB{m4721c35_423_v32y_c0mm0n_1n_3m83dd3d_d3v1c35!@&325$}
