Rating:
## [Where did he GO?](https://infernoctf.live/challenges#Where%20did%20he%20GO?)
Reversing, 50 Points
Author: Unknown
Writeup By: **-0x1C**
>Get Set GO...
>Flag Format: infernoCTF{#string_here}
File Attached: [test.go](https://web.archive.org/web/20191228072229/https://infernoctf.live/files/8b9fd7e9c1ef8ca67dd8165f314af7c8/test.go?token=eyJ0ZWFtX2lkIjo3OCwidXNlcl9pZCI6MjU2LCJmaWxlX2lkIjoxMH0.XgcCBg.LUsVJllpOsczkcHoWrQmh8WunYM)
## Solution:
Opening the .go file in a text editor will show us the source code of the program at hand.
```go
package main
import (
"fmt"
"strings"
"os"
"bufio";
)
func jai_ram_ji_ki(s string) string {
chars := []rune(s)
for i, j := 0, len(chars)-1; i < j; i, j = i+1, j-1 {
chars[i], chars[j] = chars[j], chars[i]
}
return string(chars)
}
func EncryptDecrypt(input, key string) (output string) {
for i := 0; i < len(input); i++ {
output += string(input[i] ^ key[i % len(key)])
}
return output
}
func mandir_wahi_banega(s string) string {
words := strings.Fields(s)
for i, j := 0, len(words)-1; i < j; i, j = i+1, j-1 {
words[i], words[j] = jai_ram_ji_ki(words[j]), jai_ram_ji_ki(words[i])
}
return strings.Join(words, "_")
}
func main() {
fmt.Print("Enter Password: ");
user_input,_,err := bufio.NewReader(os.Stdin).ReadLine();
if err != nil {
fmt.Println("Something is wrong with your computer, ",err);
}
ency := string([]byte{33,33,116,65,51,114,71,95,115,49,95,103,110,49,77,77,97,82,103,48,114,80,95,48,103})
if jai_ram_ji_ki(mandir_wahi_banega(string(user_input))) == ency {
fmt.Println("You Cracked it, A Hero is born");
} else {
fmt.Println("Don't Worry, Relax, Chill and Try harder");
}
}
```
Giving the main() function a look, we can see that the program will read in an input and check if `jai_ram_ji_ki(mandir_wahi_banega(string(user_input))) == ency`
Although this might seem complicated, we can see that all we need to do to get the solution is have a string that evaluates to the value of the string `ency`.
We are given the string `ency` in its char bytes, `[]byte{33,33,116,65,51,114,71,95,115,49,95,103,110,49,77,77,97,82,103,48,114,80,95,48,103}`, which we can easily reverse back to plaintext by converting them from hex to ascii characters, then reversing the string.
A basic script to grab the flag from the bytes can be made as such
```python
original_string = [33,33,116,65,51,114,71,95,115,49,95,103,110,49,77,77,97,82,103,48,114,80,95,48,103]
final_string = ""
# Iterate through each character in original_string
for current_character in original_string:
final_string += chr(current_character) # Add each character into final_string
print(final_string[::-1]) # Reverse the final string
```
The output of this script will be the flag!
Flag: `infernoCTF{g0_Pr0gRaMM1ng_1s_Gr3At!!}`
