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-rw-r--r--src/afl-fuzz-python.c402
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diff --git a/src/afl-fuzz-python.c b/src/afl-fuzz-python.c
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+/*
+ american fuzzy lop - fuzzer code
+ --------------------------------
+
+ Written and maintained by Michal Zalewski <lcamtuf@google.com>
+
+ Forkserver design by Jann Horn <jannhorn@googlemail.com>
+
+ Copyright 2013, 2014, 2015, 2016, 2017 Google Inc. All rights reserved.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at:
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ This is the real deal: the program takes an instrumented binary and
+ attempts a variety of basic fuzzing tricks, paying close attention to
+ how they affect the execution path.
+
+ */
+
+#include "afl-fuzz.h"
+
+/* Python stuff */
+#ifdef USE_PYTHON
+
+int init_py() {
+
+ Py_Initialize();
+ u8* module_name = getenv("AFL_PYTHON_MODULE");
+
+ if (module_name) {
+
+ PyObject* py_name = PyString_FromString(module_name);
+
+ py_module = PyImport_Import(py_name);
+ Py_DECREF(py_name);
+
+ if (py_module != NULL) {
+
+ u8 py_notrim = 0;
+ py_functions[PY_FUNC_INIT] = PyObject_GetAttrString(py_module, "init");
+ py_functions[PY_FUNC_FUZZ] = PyObject_GetAttrString(py_module, "fuzz");
+ py_functions[PY_FUNC_INIT_TRIM] =
+ PyObject_GetAttrString(py_module, "init_trim");
+ py_functions[PY_FUNC_POST_TRIM] =
+ PyObject_GetAttrString(py_module, "post_trim");
+ py_functions[PY_FUNC_TRIM] = PyObject_GetAttrString(py_module, "trim");
+
+ for (u8 py_idx = 0; py_idx < PY_FUNC_COUNT; ++py_idx) {
+
+ if (!py_functions[py_idx] || !PyCallable_Check(py_functions[py_idx])) {
+
+ if (py_idx >= PY_FUNC_INIT_TRIM && py_idx <= PY_FUNC_TRIM) {
+
+ // Implementing the trim API is optional for now
+ if (PyErr_Occurred()) PyErr_Print();
+ py_notrim = 1;
+
+ } else {
+
+ if (PyErr_Occurred()) PyErr_Print();
+ fprintf(stderr,
+ "Cannot find/call function with index %d in external "
+ "Python module.\n",
+ py_idx);
+ return 1;
+
+ }
+
+ }
+
+ }
+
+ if (py_notrim) {
+
+ py_functions[PY_FUNC_INIT_TRIM] = NULL;
+ py_functions[PY_FUNC_POST_TRIM] = NULL;
+ py_functions[PY_FUNC_TRIM] = NULL;
+ WARNF(
+ "Python module does not implement trim API, standard trimming will "
+ "be used.");
+
+ }
+
+ PyObject *py_args, *py_value;
+
+ /* Provide the init function a seed for the Python RNG */
+ py_args = PyTuple_New(1);
+ py_value = PyInt_FromLong(UR(0xFFFFFFFF));
+ if (!py_value) {
+
+ Py_DECREF(py_args);
+ fprintf(stderr, "Cannot convert argument\n");
+ return 1;
+
+ }
+
+ PyTuple_SetItem(py_args, 0, py_value);
+
+ py_value = PyObject_CallObject(py_functions[PY_FUNC_INIT], py_args);
+
+ Py_DECREF(py_args);
+
+ if (py_value == NULL) {
+
+ PyErr_Print();
+ fprintf(stderr, "Call failed\n");
+ return 1;
+
+ }
+
+ } else {
+
+ PyErr_Print();
+ fprintf(stderr, "Failed to load \"%s\"\n", module_name);
+ return 1;
+
+ }
+
+ }
+
+ return 0;
+
+}
+
+void finalize_py() {
+
+ if (py_module != NULL) {
+
+ u32 i;
+ for (i = 0; i < PY_FUNC_COUNT; ++i)
+ Py_XDECREF(py_functions[i]);
+
+ Py_DECREF(py_module);
+
+ }
+
+ Py_Finalize();
+
+}
+
+void fuzz_py(char* buf, size_t buflen, char* add_buf, size_t add_buflen,
+ char** ret, size_t* retlen) {
+
+ if (py_module != NULL) {
+
+ PyObject *py_args, *py_value;
+ py_args = PyTuple_New(2);
+ py_value = PyByteArray_FromStringAndSize(buf, buflen);
+ if (!py_value) {
+
+ Py_DECREF(py_args);
+ fprintf(stderr, "Cannot convert argument\n");
+ return;
+
+ }
+
+ PyTuple_SetItem(py_args, 0, py_value);
+
+ py_value = PyByteArray_FromStringAndSize(add_buf, add_buflen);
+ if (!py_value) {
+
+ Py_DECREF(py_args);
+ fprintf(stderr, "Cannot convert argument\n");
+ return;
+
+ }
+
+ PyTuple_SetItem(py_args, 1, py_value);
+
+ py_value = PyObject_CallObject(py_functions[PY_FUNC_FUZZ], py_args);
+
+ Py_DECREF(py_args);
+
+ if (py_value != NULL) {
+
+ *retlen = PyByteArray_Size(py_value);
+ *ret = malloc(*retlen);
+ memcpy(*ret, PyByteArray_AsString(py_value), *retlen);
+ Py_DECREF(py_value);
+
+ } else {
+
+ PyErr_Print();
+ fprintf(stderr, "Call failed\n");
+ return;
+
+ }
+
+ }
+
+}
+
+u32 init_trim_py(char* buf, size_t buflen) {
+
+ PyObject *py_args, *py_value;
+
+ py_args = PyTuple_New(1);
+ py_value = PyByteArray_FromStringAndSize(buf, buflen);
+ if (!py_value) {
+
+ Py_DECREF(py_args);
+ FATAL("Failed to convert arguments");
+
+ }
+
+ PyTuple_SetItem(py_args, 0, py_value);
+
+ py_value = PyObject_CallObject(py_functions[PY_FUNC_INIT_TRIM], py_args);
+ Py_DECREF(py_args);
+
+ if (py_value != NULL) {
+
+ u32 retcnt = PyInt_AsLong(py_value);
+ Py_DECREF(py_value);
+ return retcnt;
+
+ } else {
+
+ PyErr_Print();
+ FATAL("Call failed");
+
+ }
+
+}
+
+u32 post_trim_py(char success) {
+
+ PyObject *py_args, *py_value;
+
+ py_args = PyTuple_New(1);
+
+ py_value = PyBool_FromLong(success);
+ if (!py_value) {
+
+ Py_DECREF(py_args);
+ FATAL("Failed to convert arguments");
+
+ }
+
+ PyTuple_SetItem(py_args, 0, py_value);
+
+ py_value = PyObject_CallObject(py_functions[PY_FUNC_POST_TRIM], py_args);
+ Py_DECREF(py_args);
+
+ if (py_value != NULL) {
+
+ u32 retcnt = PyInt_AsLong(py_value);
+ Py_DECREF(py_value);
+ return retcnt;
+
+ } else {
+
+ PyErr_Print();
+ FATAL("Call failed");
+
+ }
+
+}
+
+void trim_py(char** ret, size_t* retlen) {
+
+ PyObject *py_args, *py_value;
+
+ py_args = PyTuple_New(0);
+ py_value = PyObject_CallObject(py_functions[PY_FUNC_TRIM], py_args);
+ Py_DECREF(py_args);
+
+ if (py_value != NULL) {
+
+ *retlen = PyByteArray_Size(py_value);
+ *ret = malloc(*retlen);
+ memcpy(*ret, PyByteArray_AsString(py_value), *retlen);
+ Py_DECREF(py_value);
+
+ } else {
+
+ PyErr_Print();
+ FATAL("Call failed");
+
+ }
+
+}
+
+u8 trim_case_python(char** argv, struct queue_entry* q, u8* in_buf) {
+
+ static u8 tmp[64];
+ static u8 clean_trace[MAP_SIZE];
+
+ u8 needs_write = 0, fault = 0;
+ u32 trim_exec = 0;
+ u32 orig_len = q->len;
+
+ stage_name = tmp;
+ bytes_trim_in += q->len;
+
+ /* Initialize trimming in the Python module */
+ stage_cur = 0;
+ stage_max = init_trim_py(in_buf, q->len);
+
+ if (not_on_tty && debug)
+ SAYF("[Python Trimming] START: Max %d iterations, %u bytes", stage_max,
+ q->len);
+
+ while (stage_cur < stage_max) {
+
+ sprintf(tmp, "ptrim %s", DI(trim_exec));
+
+ u32 cksum;
+
+ char* retbuf = NULL;
+ size_t retlen = 0;
+
+ trim_py(&retbuf, &retlen);
+
+ if (retlen > orig_len)
+ FATAL(
+ "Trimmed data returned by Python module is larger than original "
+ "data");
+
+ write_to_testcase(retbuf, retlen);
+
+ fault = run_target(argv, exec_tmout);
+ ++trim_execs;
+
+ if (stop_soon || fault == FAULT_ERROR) goto abort_trimming;
+
+ cksum = hash32(trace_bits, MAP_SIZE, HASH_CONST);
+
+ if (cksum == q->exec_cksum) {
+
+ q->len = retlen;
+ memcpy(in_buf, retbuf, retlen);
+
+ /* Let's save a clean trace, which will be needed by
+ update_bitmap_score once we're done with the trimming stuff. */
+
+ if (!needs_write) {
+
+ needs_write = 1;
+ memcpy(clean_trace, trace_bits, MAP_SIZE);
+
+ }
+
+ /* Tell the Python module that the trimming was successful */
+ stage_cur = post_trim_py(1);
+
+ if (not_on_tty && debug)
+ SAYF("[Python Trimming] SUCCESS: %d/%d iterations (now at %u bytes)",
+ stage_cur, stage_max, q->len);
+
+ } else {
+
+ /* Tell the Python module that the trimming was unsuccessful */
+ stage_cur = post_trim_py(0);
+ if (not_on_tty && debug)
+ SAYF("[Python Trimming] FAILURE: %d/%d iterations", stage_cur,
+ stage_max);
+
+ }
+
+ /* Since this can be slow, update the screen every now and then. */
+
+ if (!(trim_exec++ % stats_update_freq)) show_stats();
+
+ }
+
+ if (not_on_tty && debug)
+ SAYF("[Python Trimming] DONE: %u bytes -> %u bytes", orig_len, q->len);
+
+ /* If we have made changes to in_buf, we also need to update the on-disk
+ version of the test case. */
+
+ if (needs_write) {
+
+ s32 fd;
+
+ unlink(q->fname); /* ignore errors */
+
+ fd = open(q->fname, O_WRONLY | O_CREAT | O_EXCL, 0600);
+
+ if (fd < 0) PFATAL("Unable to create '%s'", q->fname);
+
+ ck_write(fd, in_buf, q->len, q->fname);
+ close(fd);
+
+ memcpy(trace_bits, clean_trace, MAP_SIZE);
+ update_bitmap_score(q);
+
+ }
+
+abort_trimming:
+
+ bytes_trim_out += q->len;
+ return fault;
+
+}
+
+#endif /* USE_PYTHON */
+
generated by cgit v1.2.3 (git 2.25.1) at 2026-01-14 23:18:18 +0000