feat: frequency analysis with the bruteforce

Author: disalad

project/__main__.py

@@ -1,4 +1,5 @@
-from .handlers import bruteforce_handler, decrypt_handler, encrypt_handler, freq_analysis_handler
+from .handlers import bruteforce_handler, decrypt_handler, encrypt_handler, freq_analysis_handler, brute_freq_handler
+from colorama import Fore, Style
 import argparse
 
 parser = argparse.ArgumentParser(
@@ -26,10 +27,16 @@
                     metavar='PLAIN', help='Cipher text to crack', type=str)
 
 # -fr & --freq-analysis
-parser.add_argument('-fr', '--freq-analysis', nargs='+', metavar='CIPHER', help='Cipher text to crack by analysing', type=str)
+parser.add_argument('-fr', '--freq-analysis', nargs='+', metavar='CIPHER',
+                    help='Plain text to crack by analysing', type=str)
 
 # -w & --wordlist
-parser.add_argument('-w', '--wordlist', nargs=1, metavar='WORDLIST', help='Path to the wordlist containing language words', type=str)
+parser.add_argument('-w', '--wordlist', nargs=1, metavar='WORDLIST',
+                    help='Path to the wordlist containing language words', type=str)
+
+# -bfr & --brute-frequency
+parser.add_argument('-bfr', '--brute-frequency', nargs='+', metavar='CIPHER',
+                    help='Cipher to crack and analyse output for the text containing words in a wordlist')
 
 args = parser.parse_args()
 
@@ -39,6 +46,10 @@ def handle_args():
         # If key isn't in the args,
         if not args.key and (args.encrypt or args.decrypt):
             raise NameError("Key is not defined")
+        # If brute frequency flag used,
+        elif args.brute_frequency:
+            brute_freq_handler(args)
+        # If frequency flag used,
         elif args.freq_analysis:
             freq_analysis_handler(args)
         # If the bruteforce flag used
@@ -54,4 +65,4 @@ def handle_args():
         else:
             raise ValueError("No Arguments given")
     except Exception as e:
-        print("Error:", e)
+        print(f'{Fore.LIGHTRED_EX}Error: {e}{Style.RESET_ALL}')

project/crack.py

@@ -1,7 +1,29 @@
 from .crypt import ALPHEBET, decrypt
+from .utils import analyse_text
+from operator import itemgetter
+import re
+
 
 def bruteforce(text):
     cracked = []
+    # Iterate from 1 to length of the ALPHEBET
     for i in range(1, len(ALPHEBET)):
         cracked.append('Result with key ' + str(i) + ' ' + decrypt(text, i))
     return cracked
+
+
+def brute_freq(text, wordlist):
+    analysed = {}
+    decrypted = []
+    # Bruteforce and get all possibilities
+    for i in range(len(ALPHEBET)):
+        decrypted.append(decrypt(text, i))
+    # Check whether the given words are present in the given wordlist or not
+    for text in decrypted:
+        text = re.sub(r'[^A-Za-z0-9 ]+', '', text)
+        matches = analyse_text(text, wordlist)
+        avg = float(matches) / len(text.split(' ')) * 100
+        analysed[text] = avg
+    # Sort the analysed texts by average
+    analysed = dict(sorted(analysed.items(), key=itemgetter(1), reverse=True))
+    return analysed

project/handlers.py

@@ -1,6 +1,7 @@
-from .crack import bruteforce
+from .crack import bruteforce, brute_freq
 from .utils import write_file, analyse_text
 from .crypt import encrypt, decrypt
+from colorama import Fore, Style
 import re
 
 
@@ -66,12 +67,38 @@ def decrypt_handler(args):
 
 
 def freq_analysis_handler(args):
+    # Check for missing arguments
+    if not args.wordlist:
+        raise ValueError("No Wordlist Found")
     text = ''
     a_value = ' '.join(args.freq_analysis)
+    # Filter letters, numbers and spaces
     text = re.sub(r'[^A-Za-z0-9 ]+', '', a_value)
+    # Analyse the frequency
     matches = analyse_text(text, ''.join(args.wordlist))
-    l = len(text.split(' '))
     avg = float(matches) / len(text.split(' ')) * 100
-    if avg > 80:
-        print('True')
-    print('False')
+    if avg > 60:
+        print(f'{Fore.GREEN}True with an average of {round(avg, 1)}%{Style.RESET_ALL}')
+        return
+    print(f'{Fore.YELLOW}False with an average of {round(avg, 1)}%{Style.RESET_ALL}')
+
+
+def brute_freq_handler(args):
+    c_value = ' '.join(args.brute_frequency)
+    # Get cipher text
+    cipher = open(c_value, 'r').read() if args.sourceFile else c_value
+    # Get analysed disctionary
+    analyzed = brute_freq(cipher, ''.join(args.wordlist))
+    # Write to the file,
+    # If an output path specified
+    if args.output:
+        write_file(analyzed, args.output)
+    else:
+        found = False
+        for i in analyzed:
+            if analyzed[i] > 60:
+                print(f'{Fore.GREEN}{round(analyzed[i], 1)}%{Style.RESET_ALL} : {i}')
+                found = True
+        if not found:
+            print(
+                f'{Fore.YELLOW}No Matching Sentences Found For The Given Wordlist{Style.RESET_ALL}')