1 files changed, 58 insertions, 0 deletions
diff --git a/python/examples/encoded_strings.py b/python/examples/encoded_strings.py
new file mode 100644
index 00000000..ce7d02db
--- /dev/null
+++ b/python/examples/encoded_strings.py
@@ -0,0 +1,58 @@
+from binaryninja import (ConstantRenderer, PointerType, InstructionTextToken, InstructionTextTokenType, DataBuffer)
+
+
+class EncodedStringConstantRenderer(ConstantRenderer):
+    renderer_name = "encoded_strings"
+    decoders = {
+        "xor_encoded": lambda encoded, key: encoded ^ key,
+        "sub_encoded": lambda encoded, key: (encoded - key) & 0xff,
+        "add_encoded": lambda encoded, key: (encoded + key) & 0xff
+    }
+
+    def is_valid_for_type(self, func, type):
+        if not isinstance(type, PointerType):
+            return False
+        for name in self.__class__.decoders.keys():
+            if name in type.target.attributes:
+                return True
+        return False
+
+    def render_constant_pointer(self, instr, type, val, tokens, settings, precedence):
+        if not isinstance(type, PointerType):
+            return False
+
+        values = None
+        decoder = None
+        for name in self.__class__.decoders.keys():
+            if name in type.target.attributes:
+                try:
+                    values = bytes.fromhex(type.target.attributes[name])
+                    decoder = self.__class__.decoders[name]
+                except:
+                    return False
+        if values is None or decoder is None:
+            return False
+
+        encoded_null = "encoded_null" in type.target.attributes
+
+        result = b""
+        i = 0
+        while True:
+            byte = instr.function.view.read(val + i, 1)
+            if len(byte) != 1:
+                return False
+            if not encoded_null and byte[0] == 0:
+                break
+            byte = decoder(byte[0], values[i % len(values)])
+            if byte == 0:
+                break
+            result += bytes([byte])
+            i += 1
+
+        tokens.append(InstructionTextToken(InstructionTextTokenType.BraceToken, "\""))
+        tokens.append(InstructionTextToken(InstructionTextTokenType.StringToken, DataBuffer(result).escape()))
+        tokens.append(InstructionTextToken(InstructionTextTokenType.BraceToken, "\"_enc"))
+        return True
+
+
+EncodedStringConstantRenderer().register()