got the flag

hashcash.py

@@ -15,24 +15,22 @@ rand_chars = ([chr(x) for x in range(ord('a'), ord('z'))] +
               [chr(x) for x in range(ord('0'), ord('9'))] +
               ['+', '-', '/'])
 
-
-char_map = {'0' : '0000',
-            '1' : '0001',
-            '2' : '0010',
-            '3' : '0011',
-            '4' : '0100',
-            '5' : '0101',
-            '6' : '0110',
-            '7' : '0111',
-            '8' : '1000',
-            '9' : '1001',
-            'a' : '1010',
-            'b' : '1011',
-            'c' : '1100',
-            'd' : '1101',
-            'e' : '1110',
-            'f' : '1111'}
-
+char_map = {'0': '0000',
+            '1': '0001',
+            '2': '0010',
+            '3': '0011',
+            '4': '0100',
+            '5': '0101',
+            '6': '0110',
+            '7': '0111',
+            '8': '1000',
+            '9': '1001',
+            'a': '1010',
+            'b': '1011',
+            'c': '1100',
+            'd': '1101',
+            'e': '1110',
+            'f': '1111'}
 
 rc_len = len(rand_chars)
 
@@ -41,16 +39,18 @@ min_bits = 0
 max_bits = 160
 default_bits = 15
 
-def is_valid(stamp : str) -> bool:
+
+def is_valid(stamp: str) -> bool:
     return validate(int(stamp.split(':')[1]), stamp)
 
-def validate(nbits : int, stamp : str, encoding : str ='utf-8') -> bool:
+
+def validate(nbits: int, stamp: str, encoding: str = 'utf-8') -> bool:
     if nbits < min_bits or nbits > max_bits:
         raise ValueError("Param 'nbits' must be in range [0, 160), but is {}".format(nbits))
 
     i = 0
     total = 0
-    N = int(nbits/8)
+    N = int(nbits / 8)
     hashed = sha1(stamp.encode(encoding)).digest()
 
     while i < N:
@@ -63,19 +63,19 @@ def validate(nbits : int, stamp : str, encoding : str ='utf-8') -> bool:
 
     return total == 0
 
-def generate(nbits : int, resource : str, encoding : str ='utf-8') -> str:
+
+def generate(nbits: int, resource: str, encoding: str = 'utf-8') -> str:
     # ver:bits:date:resource:[ext]:rand:counter
     ver = 1
     bits = nbits
     date_str = datetime.utcnow().strftime("%Y%m%d%H%M%S")
     ext = ''
-    rand = ''.join(rand_chars[randint(0, rc_len-1)] for x in range(0, 10))
+    rand = ''.join(rand_chars[randint(0, rc_len - 1)] for x in range(0, 10))
     counter = 0
 
     result = None
     while result is None:
-        #stamp = ":".join(str(elem) for elem in [ver, bits, date_str, resource, ext, rand, counter])
-        stamp = "{}{}".format(resource,counter)
+        stamp = "{}{}".format(resource, counter)
 
         if validate(nbits, stamp, encoding=encoding):
             result = stamp
@@ -84,22 +84,3 @@ def generate(nbits : int, resource : str, encoding : str ='utf-8') -> str:
         counter += 1
 
     return result
-
-
-if __name__ == "__main__":
-
-    from argparse import ArgumentParser
-    parser = ArgumentParser()
-
-    parser.add_argument("NBITS", type=int, default=default_bits, help="Number of leading zeroes in a stamp", choices=range(max_bits+1))
-    parser.add_argument("RESOURCE", help="The resource string to use in the stamp. Ex: email address, ip address, etc")
-    parser.add_argument('-v', '--validate', action='store_true', help="Validate RESOURCE as a HashCash stamp")
-
-    args = parser.parse_args()
-
-    func = generate
-
-    if args.validate:
-        func = validate
-
-    print(func(args.NBITS, args.RESOURCE))

netsec.py

@@ -6,6 +6,7 @@ import socket
 import hashlib
 import requests
 import sympy
+import hashcash
 """
 requirements:
     sympy
@@ -54,6 +55,11 @@ def sha1_magic(s, last_solution):
     print(digest)
     s.send(digest.encode())
     print(s.recv(1024).decode())
+    newstring = hashcash.generate(16, 'Y8O353{}'.format(last_solution))
+    print(s.recv(1024).decode())
+    print(newstring)
+    s.send(newstring.encode())
+    print(s.recv(1024).decode())
 
 
 def http_comm():
@@ -69,7 +75,7 @@ def http_comm():
 def https_comm():
     sess = requests.Session()
     url = "https://152.66.249.144/"
-    flag = sess.get(url, cert=("/tmp/clientcert.pem", "/tmp/clientkey.pem"), verify=False)
+    flag = sess.get(url, cert=("/tmp/clientcert.pem", "/tmp/clientkey.pem"), verify=False, headers={'User-Agent': 'CrySyS'})
     print(flag.content)
 
 
@@ -90,7 +96,7 @@ def numbre_crunch(s):
         solution = sympy.sympify(problem_statement_for.split('.')[1].split('=')[0])
         print(solution)
         s.send(str(solution).encode())
-        last_solution=solution
+        last_solution = solution
 
     return last_solution
 
@@ -99,4 +105,6 @@ if __name__ == '__main__':
     knock()
     server_communicate()
     http_comm()
-    #https_comm()
+    https_comm()
+
+# FLAG: YouCanHandleNetworking-Y8O353-1d66de