added training

training/srdnlenctf-2025/anodic_music/solve_hashset.py

@@ -0,0 +1,31 @@
+import hashlib
+import string
+
+MD5_LEN = 16
+
+#Create hashset
+def import_bank(path="./hardcore.bnk"):
+    hashes = open(path, 'rb').read()
+    res = set()
+    for i in range(len(hashes)//MD5_LEN):
+        res.add(hashes[i*MD5_LEN:(i+1)*MD5_LEN])
+    return res
+
+bank = import_bank()
+
+FLAG_LEN = 62
+
+def dfs(substr=""):
+    subh = hashlib.md5(substr.encode('ascii')).digest()
+    print(f"Testing {substr}")
+    #First, check if current substring is in blacklist.
+    if subh not in bank:
+        #If substring is full flag, print and return
+        if len(substr) == FLAG_LEN:
+            print(substr)
+            exit()
+        for c in string.printable:
+            dfs(substr+c)
+    return    
+
+dfs()