about summary refs log tree commit diff
path: root/custom_mutators/examples/wrapper_afl_min.py
diff options
context:
space:
mode:
Diffstat (limited to 'custom_mutators/examples/wrapper_afl_min.py')
-rw-r--r--custom_mutators/examples/wrapper_afl_min.py123
1 files changed, 123 insertions, 0 deletions
diff --git a/custom_mutators/examples/wrapper_afl_min.py b/custom_mutators/examples/wrapper_afl_min.py
new file mode 100644
index 00000000..5cd60031
--- /dev/null
+++ b/custom_mutators/examples/wrapper_afl_min.py
@@ -0,0 +1,123 @@
+#!/usr/bin/env python
+
+from XmlMutatorMin import XmlMutatorMin
+
+# Default settings (production mode)
+
+__mutator__ = None
+__seed__ = "RANDOM"
+__log__ = False
+__log_file__ = "wrapper.log"
+
+
+# AFL functions
+def log(text):
+    """
+    Logger
+    """
+
+    global __seed__
+    global __log__
+    global __log_file__
+
+    if __log__:
+        with open(__log_file__, "a") as logf:
+            logf.write("[%s] %s\n" % (__seed__, text))
+
+
+def init(seed):
+    """
+    Called once when AFL starts up. Seed is used to identify the AFL instance in log files
+    """
+
+    global __mutator__
+    global __seed__
+
+    # Get the seed
+    __seed__ = seed
+
+    # Create a global mutation class
+    try:
+        __mutator__ = XmlMutatorMin(__seed__, verbose=__log__)
+        log("init(): Mutator created")
+    except RuntimeError as e:
+        log("init(): Can't create mutator: %s" % e.message)
+
+
+def fuzz(buf, add_buf, max_size):
+    """
+    Called for each fuzzing iteration.
+    """
+
+    global __mutator__
+
+    # Do we have a working mutator object?
+    if __mutator__ is None:
+        log("fuzz(): Can't fuzz, no mutator available")
+        return buf
+
+    # Try to use the AFL buffer
+    via_buffer = True
+
+    # Interpret the AFL buffer (an array of bytes) as a string
+    if via_buffer:
+        try:
+            buf_str = str(buf)
+            log("fuzz(): AFL buffer converted to a string")
+        except Exception:
+            via_buffer = False
+            log("fuzz(): Can't convert AFL buffer to a string")
+
+    # Load XML from the AFL string
+    if via_buffer:
+        try:
+            __mutator__.init_from_string(buf_str)
+            log(
+                "fuzz(): Mutator successfully initialized with AFL buffer (%d bytes)"
+                % len(buf_str)
+            )
+        except Exception:
+            via_buffer = False
+            log("fuzz(): Can't initialize mutator with AFL buffer")
+
+    # If init from AFL buffer wasn't succesful
+    if not via_buffer:
+        log("fuzz(): Returning unmodified AFL buffer")
+        return buf
+
+    # Sucessful initialization -> mutate
+    try:
+        __mutator__.mutate(max=5)
+        log("fuzz(): Input mutated")
+    except Exception:
+        log("fuzz(): Can't mutate input => returning buf")
+        return buf
+
+    # Convert mutated data to a array of bytes
+    try:
+        data = bytearray(__mutator__.save_to_string())
+        log("fuzz(): Mutated data converted as bytes")
+    except Exception:
+        log("fuzz(): Can't convert mutated data to bytes => returning buf")
+        return buf
+
+    # Everything went fine, returning mutated content
+    log("fuzz(): Returning %d bytes" % len(data))
+    return data
+
+
+# Main (for debug)
+if __name__ == "__main__":
+
+    __log__ = True
+    __log_file__ = "/dev/stdout"
+    __seed__ = "RANDOM"
+
+    init(__seed__)
+
+    in_1 = bytearray(
+        "<foo ddd='eeee'>ffff<a b='c' d='456' eee='ffffff'>zzzzzzzzzzzz</a><b yyy='YYY' zzz='ZZZ'></b></foo>"
+    )
+    in_2 = bytearray("<abc abc123='456' abcCBA='ppppppppppppppppppppppppppppp'/>")
+    out = fuzz(in_1, in_2)
+    print(out)