Add script to recover PKs

tools/recover_pk.py

@@ -0,0 +1,75 @@
+#!/usr/bin/env python3
+
+# @doegox -- 2020
+
+import sslcrypto
+import binascii
+import sys
+
+debug = False
+
+def recover(data, signature):
+    recovered = set()
+    alghash = None
+    if len(signature) == 32:
+        curve = sslcrypto.ecc.get_curve("secp128r1")
+        recoverable = False
+    elif len(signature) == 33:
+        curve = sslcrypto.ecc.get_curve("secp128r1")
+        recoverable = True
+    elif len(signature) == 56:
+        curve = sslcrypto.ecc.get_curve("secp224r1")
+        recoverable = False
+    elif len(signature) == 57:
+        curve = sslcrypto.ecc.get_curve("secp224r1")
+        recoverable = True
+    else:
+        print("Unsupported signature size %i" % len(signature))
+        exit(1)
+
+    if (recoverable):
+        try:
+            pk = curve.recover(signature, data, hash=alghash)
+            recovered.add(pk)
+            if debug:
+                print("Possible Pk:    ", binascii.hexlify(pk))
+        except:
+            pass
+    else:
+        for i in range(2):
+            # Brute force RECID
+            recid = bytes([27+i])
+            try:
+                pk = curve.recover(recid + signature, data, hash=alghash)
+                recovered.add(pk)
+                if debug:
+                    print("Possible Pk:    ", binascii.hexlify(pk))
+            except:
+                pass
+    return recovered
+
+if len(sys.argv) < 3 or len(sys.argv) % 2 == 0:
+    print("Usage:   \n%s UID SIGN [UID SIGN] [...]" % sys.argv[0])
+    print("Example: \n%s 04ee45daa34084 ebb6102bff74b087d18a57a54bc375159a04ea9bc61080b7f4a85afe1587d73b" % sys.argv[0])
+    exit(1)
+
+recovered = set()
+for i in range(1, len(sys.argv), 2):
+    data = binascii.unhexlify(sys.argv[i])
+    if debug:
+        print("UID       (%2i): " %  len(data), binascii.hexlify(data))
+    signature = binascii.unhexlify(sys.argv[i+1])
+    if debug:
+        print("Signature (%2i): " % len(signature), binascii.hexlify(signature))
+    recovered_tmp = recover(data, signature)
+    if i == 1:
+        if recovered_tmp == set():
+            break
+        else:
+            recovered = recovered_tmp
+    else:
+        recovered &= recovered_tmp
+
+print("Possible uncompressed Pk(s):")
+for pk in list(recovered):
+    print(binascii.hexlify(pk).decode('utf8'))