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-rw-r--r--examples/persistent_demo/persistent_demo.c14
-rw-r--r--examples/persistent_demo/persistent_demo_new.c118
2 files changed, 130 insertions, 2 deletions
diff --git a/examples/persistent_demo/persistent_demo.c b/examples/persistent_demo/persistent_demo.c
index 36f12850..41cd9e38 100644
--- a/examples/persistent_demo/persistent_demo.c
+++ b/examples/persistent_demo/persistent_demo.c
@@ -63,7 +63,7 @@ int main(int argc, char **argv) {
                We just have some trivial inline code that faults on 'foo!'. */
 
     /* do we have enough data? */
-    if (len < 4) return 0;
+    if (len < 8) return 0;
 
     if (buf[0] == 'f') {
 
@@ -77,7 +77,17 @@ int main(int argc, char **argv) {
           if (buf[3] == '!') {
 
             printf("four\n");
-            abort();
+            if (buf[4] == '!') {
+
+              printf("five\n");
+              if (buf[5] == '!') {
+
+                printf("six\n");
+                abort();
+
+              }
+
+            }
 
           }
 
diff --git a/examples/persistent_demo/persistent_demo_new.c b/examples/persistent_demo/persistent_demo_new.c
new file mode 100644
index 00000000..fffd40b6
--- /dev/null
+++ b/examples/persistent_demo/persistent_demo_new.c
@@ -0,0 +1,118 @@
+/*
+   american fuzzy lop++ - persistent mode example
+   --------------------------------------------
+
+   Originally written by Michal Zalewski
+
+   Copyright 2015 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 file demonstrates the high-performance "persistent mode" that may be
+   suitable for fuzzing certain fast and well-behaved libraries, provided that
+   they are stateless or that their internal state can be easily reset
+   across runs.
+
+   To make this work, the library and this shim need to be compiled in LLVM
+   mode using afl-clang-fast (other compiler wrappers will *not* work).
+
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <string.h>
+
+__AFL_FUZZ_INIT();
+
+unsigned int crc32_for_byte(unsigned int r) {
+
+  for (int j = 0; j < 8; ++j)
+    r = (r & 1 ? 0 : (unsigned int)0xEDB88320L) ^ r >> 1;
+  return r ^ (unsigned int)0xFF000000L;
+
+}
+
+unsigned int crc32(unsigned char *data, unsigned int n_bytes) {
+
+  static unsigned char table[0x100];
+  unsigned int         crc = 0;
+  if (!*table)
+    for (unsigned int i = 0; i < 0x100; ++i)
+      table[i] = crc32_for_byte(i);
+  for (unsigned int i = 0; i < n_bytes; ++i)
+    crc = table[(unsigned char)crc ^ (data)[i]] ^ crc >> 8;
+  return crc;
+
+}
+
+/* Main entry point. */
+
+int main(int argc, char **argv) {
+
+  ssize_t        len;                        /* how much input did we read? */
+  unsigned char *buf;                        /* test case buffer pointer    */
+
+  /* The number passed to __AFL_LOOP() controls the maximum number of
+     iterations before the loop exits and the program is allowed to
+     terminate normally. This limits the impact of accidental memory leaks
+     and similar hiccups. */
+
+  buf = __AFL_FUZZ_TESTCASE_BUF;
+
+  while (__AFL_LOOP(1000)) {
+
+    len = __AFL_FUZZ_TESTCASE_LEN;
+
+    /* do we have enough data? */
+    if (len < 8) return 0;
+
+    if (buf[0] == 'f') {
+
+      printf("one\n");
+      if (buf[1] == 'o') {
+
+        printf("two\n");
+        if (buf[2] == 'o') {
+
+          printf("three\n");
+          if (buf[3] == '!') {
+
+            printf("four\n");
+            if (buf[4] == '!') {
+
+              printf("five\n");
+              if (buf[6] == '!') {
+
+                printf("six\n");
+                abort();
+
+              }
+
+            }
+
+          }
+
+        }
+
+      }
+
+    }
+
+    /*** END PLACEHOLDER CODE ***/
+
+  }
+
+  /* Once the loop is exited, terminate normally - AFL will restart the process
+     when this happens, with a clean slate when it comes to allocated memory,
+     leftover file descriptors, etc. */
+
+  return 0;
+
+}
+