DarkAngelStrike · qtc-de · Apr 27, 2022 · Apr 27, 2022 · Apr 27, 2022
diff --git a/README.md b/README.md
@@ -1,6 +1,93 @@
-UnwrapperPLSQL
-==============
+### UnwrapperPLSQL
 
-Oracle 10g/11g PL/SQL unwrapper 0.2 by Niels Teusink.
+----
 
-From: http://blog.teusink.net/2010/04/unwrapping-oracle-plsql-with-unwrappy.html
+This repository contains a python script capable of unwrapping *Oracle 10g/11g PL/SQL* procedures.
+A general introduction to *PL/SQL Source Text Wrapping* can be found within the
+[official oracle documentation](https://docs.oracle.com/cd/E24693_01/appdev.11203/e17126/wrap.htm).
+This documentation also contains some samples for wrapped procedures and the following procedure will
+be used for demonstration purposes:
+
+```
+CREATE OR REPLACE FUNCTION fibonacci wrapped 
+a000000
+b2
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+abcd
+8
+14a fb
+e1Yq3QQJoEoNKIeJlbgLoLdSgogwgxDcf8vWfHSKbuowFOXFKoj9MqYGqWyRxeeCUVqNVIO1
+ICqJa3yPr6e7z8GZpMH3J0Cx0uQ0B1JuysymdNDlzfTvb7QWsrLU4jGs3h8Mm49/L9nyO4Xh
+Ae06nawFpOJIAYpBf9wBVC+ZrjU/nuEtokBqCce6HWIoF6rYgz0V0W/47x5KpOnQ2i7X3kFe
+FR8K7jT7X58k8xK9uYlZv5LhV71a7A==
+```
+
+
+### Usage
+
+----
+
+When launching the script without any arguments, it expects the wrapped procedure to be passed via stdin
+and outputs the unwrapped procedure to stdout:
+
+```console
+[user@host ~]$ cat wrapped.pld | python3 unwrap.py 
+FUNCTION fibonacci (
+  N PLS_INTEGER
+) RETURN PLS_INTEGER
+AUTHID DEFINER
+IS
+  FIB_1 PLS_INTEGER := 0;
+  FIB_2 PLS_INTEGER := 1;
+BEGIN
+  IF N = 1 THEN                              
+    RETURN FIB_1;
+  ELSIF N = 2 THEN
+    RETURN FIB_2;                           
+  ELSE
+    RETURN FIBONACCI(N-2) + FIBONACCI(N-1);  
+  END IF;
+END;
+```
+
+You can also specify a file that contains a wrapped procedure as argument:
+
+```console
+[user@host ~]$ python3 unwrap.py wrapped.pld 
+FUNCTION fibonacci (
+  N PLS_INTEGER
+) RETURN PLS_INTEGER
+AUTHID DEFINER
+IS
+  FIB_1 PLS_INTEGER := 0;
+  FIB_2 PLS_INTEGER := 1;
+BEGIN
+  IF N = 1 THEN                              
+    RETURN FIB_1;
+  ELSIF N = 2 THEN
+    RETURN FIB_2;                           
+  ELSE
+    RETURN FIBONACCI(N-2) + FIBONACCI(N-1);  
+  END IF;
+END;
+```
+
+### Resources
+
+----
+
+* [Official Oracle Documentation](https://docs.oracle.com/cd/E24693_01/appdev.11203/e17126/wrap.htm).
+* [Unwrapping Oracle PLSQL - Blog Post](http://blog.teusink.net/2010/04/unwrapping-oracle-plsql-with-unwrappy.html)
diff --git a/unwrap.py b/unwrap.py
@@ -1,49 +1,140 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
 #
-# This script unwraps Oracle wrapped plb packages, does not support 9g
-# Contact: niels at teusink net / blog.teusink.net
+# This script unwraps Oracle wrapped procedures. The original version of the script
+# was published by Niels Teusink. This script represents a refactored version, where
+# the main logic is still the same. The script does not support 9g wrapped procedures.
 #
-# License: Public domain
+# Authors: 
+#   Niels Teusink   (original)
+#   Tobias Neitzel  (refactored)
 #
 import re
-import base64
-import zlib
 import sys
+import zlib
+import base64
+import hashlib
+import argparse
+import binascii
+
+
+charmap = [
+            0x3d, 0x65, 0x85, 0xb3, 0x18, 0xdb, 0xe2, 0x87, 0xf1, 0x52, 0xab, 0x63, 0x4b, 0xb5, 0xa0, 0x5f, 0x7d, 0x68, 0x7b,
+            0x9b, 0x24, 0xc2, 0x28, 0x67, 0x8a, 0xde, 0xa4, 0x26, 0x1e, 0x03, 0xeb, 0x17, 0x6f, 0x34, 0x3e, 0x7a, 0x3f, 0xd2,
+            0xa9, 0x6a, 0x0f, 0xe9, 0x35, 0x56, 0x1f, 0xb1, 0x4d, 0x10, 0x78, 0xd9, 0x75, 0xf6, 0xbc, 0x41, 0x04, 0x81, 0x61,
+            0x06, 0xf9, 0xad, 0xd6, 0xd5, 0x29, 0x7e, 0x86, 0x9e, 0x79, 0xe5, 0x05, 0xba, 0x84, 0xcc, 0x6e, 0x27, 0x8e, 0xb0,
+            0x5d, 0xa8, 0xf3, 0x9f, 0xd0, 0xa2, 0x71, 0xb8, 0x58, 0xdd, 0x2c, 0x38, 0x99, 0x4c, 0x48, 0x07, 0x55, 0xe4, 0x53,
+            0x8c, 0x46, 0xb6, 0x2d, 0xa5, 0xaf, 0x32, 0x22, 0x40, 0xdc, 0x50, 0xc3, 0xa1, 0x25, 0x8b, 0x9c, 0x16, 0x60, 0x5c,
+            0xcf, 0xfd, 0x0c, 0x98, 0x1c, 0xd4, 0x37, 0x6d, 0x3c, 0x3a, 0x30, 0xe8, 0x6c, 0x31, 0x47, 0xf5, 0x33, 0xda, 0x43,
+            0xc8, 0xe3, 0x5e, 0x19, 0x94, 0xec, 0xe6, 0xa3, 0x95, 0x14, 0xe0, 0x9d, 0x64, 0xfa, 0x59, 0x15, 0xc5, 0x2f, 0xca,
+            0xbb, 0x0b, 0xdf, 0xf2, 0x97, 0xbf, 0x0a, 0x76, 0xb4, 0x49, 0x44, 0x5a, 0x1d, 0xf0, 0x00, 0x96, 0x21, 0x80, 0x7f,
+            0x1a, 0x82, 0x39, 0x4f, 0xc1, 0xa7, 0xd7, 0x0d, 0xd1, 0xd8, 0xff, 0x13, 0x93, 0x70, 0xee, 0x5b, 0xef, 0xbe, 0x09,
+            0xb9, 0x77, 0x72, 0xe7, 0xb2, 0x54, 0xb7, 0x2a, 0xc7, 0x73, 0x90, 0x66, 0x20, 0x0e, 0x51, 0xed, 0xf8, 0x7c, 0x8f,
+            0x2e, 0xf4, 0x12, 0xc6, 0x2b, 0x83, 0xcd, 0xac, 0xcb, 0x3b, 0xc4, 0x4e, 0xc0, 0x69, 0x36, 0x62, 0x02, 0xae, 0x88,
+            0xfc, 0xaa, 0x42, 0x08, 0xa6, 0x45, 0x57, 0xd3, 0x9a, 0xbd, 0xe1, 0x23, 0x8d, 0x92, 0x4a, 0x11, 0x89, 0x74, 0x6b,
+            0x91, 0xfb, 0xfe, 0xc9, 0x01, 0xea, 0x1b, 0xf7, 0xce
+          ]
+
+
+class IntegrityException(Exception):
+    '''
+    Is raised when the wrapped procedure has an invalid checksum.
+    '''
+
+    def __init__(self, expected: str, computed: str) -> None:
+        '''
+        Initialize the IntegrityException.
+
+        Parameters:
+            expected        The expected hash value in hex format
+            computed        The computed hash value in hex format
+
+        Returns:
+            None
+        '''
+        self.expected = expected
+        self.computed = computed
+        super().__init__()
+
+def decode_wrapped(base64str: str) -> str:
+    '''
+    Decode the base64 encoded procedure, apply the mapping table to it, validate the integrity
+    of the procedure and decompress it.
+
+    Parameters:
+        base64str           base64 encoded procedure
+
+    Returns:
+        decoded             decoded and decompressed procedure
+    '''
+    decoded = bytearray()
+    base64dec = base64.b64decode(base64str)
+
+    for byte in base64dec:
+        decoded.append(charmap[byte])
+
+    sha1 = decoded[:20]
+    code = decoded[20:]
+    checksum = hashlib.sha1(code).digest()
+
+    if sha1 != checksum:
+        raise IntegrityException(binascii.hexlify(sha1).decode(), binascii.hexlify(checksum).decode())
+
+    return zlib.decompress(code).decode()
+
+
+def main() -> None:
+    '''
+    Read a wrapped Oracle 10g/11g PL/SQL procedure and output its decoded form.
+
+    Parameters:
+        None
+
+    Returns:
+        None
+    '''
+    parser = argparse.ArgumentParser(description='''Oracle 10g/11g PL/SQL unwrapper v0.3 - by Niels Teusink & Tobias Neitzel''')
+    parser.add_argument('infile', nargs='?', default=sys.stdin, type=argparse.FileType('r'), help='filepath (default: stdin)')
+    args = parser.parse_args()
+
+    length = 0
+    wrapped = ''
+    discard = True
+    pattern = re.compile(r'^[0-9a-f]+ ([0-9a-f]+)$')
+
+    for line in args.infile.readlines():
+
+        line = line.strip()
+        matches = pattern.match(line)
+
+        if matches:
+            base64len = int(matches.groups()[0], 16)
+            discard = False
+
+        elif line and not discard:
+            length += 1
+            wrapped += line
+
+    length = length + len(wrapped) - 1
+
+    if discard:
+        print('[-] Did not find required base64 length field. Input seems to be invalid.')
+        return
+
+    if base64len != length:
+        print(f'[-] Input has unexpected b64 length: {length} (expected {base64len})')
+        return
+
+    print(decode_wrapped(wrapped))
+
+
+try:
+    main()
+
+except IntegrityException as e:
+    print("[-] Decoding the wrapped procedure created an invalid checksum.")
+    print(f"[-]   Expected value: " + e.expected)
+    print(f"[-]   Computed value: " + e.computed)
 
-# simple substitution table
-charmap = [0x3d, 0x65, 0x85, 0xb3, 0x18, 0xdb, 0xe2, 0x87, 0xf1, 0x52, 0xab, 0x63, 0x4b, 0xb5, 0xa0, 0x5f, 0x7d, 0x68, 0x7b, 0x9b, 0x24, 0xc2, 0x28, 0x67, 0x8a, 0xde, 0xa4, 0x26, 0x1e, 0x03, 0xeb, 0x17, 0x6f, 0x34, 0x3e, 0x7a, 0x3f, 0xd2, 0xa9, 0x6a, 0x0f, 0xe9, 0x35, 0x56, 0x1f, 0xb1, 0x4d, 0x10, 0x78, 0xd9, 0x75, 0xf6, 0xbc, 0x41, 0x04, 0x81, 0x61, 0x06, 0xf9, 0xad, 0xd6, 0xd5, 0x29, 0x7e, 0x86, 0x9e, 0x79, 0xe5, 0x05, 0xba, 0x84, 0xcc, 0x6e, 0x27, 0x8e, 0xb0, 0x5d, 0xa8, 0xf3, 0x9f, 0xd0, 0xa2, 0x71, 0xb8, 0x58, 0xdd, 0x2c, 0x38, 0x99, 0x4c, 0x48, 0x07, 0x55, 0xe4, 0x53, 0x8c, 0x46, 0xb6, 0x2d, 0xa5, 0xaf, 0x32, 0x22, 0x40, 0xdc, 0x50, 0xc3, 0xa1, 0x25, 0x8b, 0x9c, 0x16, 0x60, 0x5c, 0xcf, 0xfd, 0x0c, 0x98, 0x1c, 0xd4, 0x37, 0x6d, 0x3c, 0x3a, 0x30, 0xe8, 0x6c, 0x31, 0x47, 0xf5, 0x33, 0xda, 0x43, 0xc8, 0xe3, 0x5e, 0x19, 0x94, 0xec, 0xe6, 0xa3, 0x95, 0x14, 0xe0, 0x9d, 0x64, 0xfa, 0x59, 0x15, 0xc5, 0x2f, 0xca, 0xbb, 0x0b, 0xdf, 0xf2, 0x97, 0xbf, 0x0a, 0x76, 0xb4, 0x49, 0x44, 0x5a, 0x1d, 0xf0, 0x00, 0x96, 0x21, 0x80, 0x7f, 0x1a, 0x82, 0x39, 0x4f, 0xc1, 0xa7, 0xd7, 0x0d, 0xd1, 0xd8, 0xff, 0x13, 0x93, 0x70, 0xee, 0x5b, 0xef, 0xbe, 0x09, 0xb9, 0x77, 0x72, 0xe7, 0xb2, 0x54, 0xb7, 0x2a, 0xc7, 0x73, 0x90, 0x66, 0x20, 0x0e, 0x51, 0xed, 0xf8, 0x7c, 0x8f, 0x2e, 0xf4, 0x12, 0xc6, 0x2b, 0x83, 0xcd, 0xac, 0xcb, 0x3b, 0xc4, 0x4e, 0xc0, 0x69, 0x36, 0x62, 0x02, 0xae, 0x88, 0xfc, 0xaa, 0x42, 0x08, 0xa6, 0x45, 0x57, 0xd3, 0x9a, 0xbd, 0xe1, 0x23, 0x8d, 0x92, 0x4a, 0x11, 0x89, 0x74, 0x6b, 0x91, 0xfb, 0xfe, 0xc9, 0x01, 0xea, 0x1b, 0xf7, 0xce]
-
-def decode_base64_package(base64str):
-	base64dec = base64.decodestring(base64str)[20:] # we strip the first 20 chars (SHA1 hash, I don't bother checking it at the moment)
-	decoded = ''
-	for byte in range(0, len(base64dec)):
-		decoded += chr(charmap[ord(base64dec[byte])])
-	return zlib.decompress(decoded)
-
-
-sys.stderr.write("=== Oracle 10g/11g PL/SQL unwrapper 0.2 - by Niels Teusink - blog.teusink.net ===\n\n" )
-if len(sys.argv) < 2:
-	sys.stderr.write("Usage: %s infile.plb [outfile]\n" % sys.argv[0])
-	sys.exit(1)
-
-infile = open(sys.argv[1])
-outfile = None
-if len(sys.argv) == 3:
-	outfile = open(sys.argv[2], 'w')
-
-lines = infile.readlines()
-for i in range(0, len(lines)):
-	# this is really naive parsing, but works on every package I've thrown at it
-	matches = re.compile(r"^[0-9a-f]+ ([0-9a-f]+)$").match(lines[i])
-	if matches:
-		base64len = int(matches.groups()[0], 16)
-		base64str = ''
-		j = 0
-		while len(base64str) < base64len:
-			j+=1
-			base64str += lines[i+j]
-		base64str = base64str.replace("\n","")
-		if outfile:
-			outfile.write(decode_base64_package(base64str) + "\n")
-		else:
-			print decode_base64_package(base64str)
+except Exception as e:
+    print('[-] Something went wrong while unwrapping the wrapped procedure.')
+    print(f'[-] {e}')