small adjustments for custom mutator

custom_mutators/simple_mutator.c

@@ -3,9 +3,10 @@
 
   Written by Khaled Yakdan <yakdan@code-intelligence.de>
 
-  This a simple mutator that assumes that the generates messages starting with one
+  This a simple mutator that assumes that the generates messages starting with
-  of the three strings GET, PUT, or DEL followed by a payload. The mutator randomly
+  one of the three strings GET, PUT, or DEL followed by a payload. The mutator
-  selects a commend and mutates the payload of the seed provided as input.
+  randomly selects a commend and mutates the payload of the seed provided as
+  input.
 */
 
 #include <stdint.h>
@@ -13,28 +14,36 @@
 #include <string.h>
 
 static const char *commands[] = {
+
     "GET",
     "PUT",
     "DEL",
+
 };
 
 static size_t data_size = 100;
 
-size_t afl_custom_mutator (uint8_t *data, size_t size, uint8_t* mutated_out, size_t max_size, unsigned int seed) {
+size_t afl_custom_mutator(uint8_t *data, size_t size, uint8_t *mutated_out,
+                          size_t max_size, unsigned int seed) {
 
   // Seed the PRNG
   srand(seed);
 
-  // Make sure that the packet size does not exceed the maximum size expected by the fuzzer
+  // Make sure that the packet size does not exceed the maximum size expected by
+  // the fuzzer
   size_t mutated_size = data_size <= max_size ? data_size : max_size;
 
   // Randomly select a command string to add as a header to the packet
   memcpy(mutated_out, commands[rand() % 3], 3);
 
   // Mutate the payload of the packet
-  for (int i = 3 ; i < mutated_size ; i++) {
+  for (int i = 3; i < mutated_size; i++) {
+
     mutated_out[i] = (data[i] + rand() % 10) & 0xff;
+
   }
 
   return mutated_size;
+
 }
+

include/afl-fuzz.h

@@ -426,20 +426,24 @@ u8* (*post_handler)(u8* buf, u32* len);
  * @param data Input data to be mutated
  * @param size Size of input data
  * @param mutated_out Buffer to store the mutated input
- * @param max_size Maximum size of the mutated output. The mutation must not produce data larger than max_size.
+ * @param max_size Maximum size of the mutated output. The mutation must not
- * @param seed Seed used for the mutation. The mutation should produce the same output given the same seed.
+ * produce data larger than max_size.
+ * @param seed Seed used for the mutation. The mutation should produce the same
+ * output given the same seed.
  * @return Size of the mutated output.
  */
-size_t (*custom_mutator)(u8 *data, size_t size, u8* mutated_out, size_t max_size, unsigned int seed);
+size_t (*custom_mutator)(u8* data, size_t size, u8* mutated_out,
+                         size_t max_size, unsigned int seed);
 /**
- * A post-processing function to use right before AFL writes the test case to disk in order to execute the target.
+ * A post-processing function to use right before AFL writes the test case to
- * If this functionality is not needed, Simply don't define this function.
+ * disk in order to execute the target. If this functionality is not needed,
+ * Simply don't define this function.
  * @param data Buffer containing the test case to be executed.
  * @param size Size of the test case.
  * @param new_data Buffer to store the test case after processing
  * @return Size of data after processing.
  */
-size_t (*pre_save_handler)(u8 *data, size_t size, u8 **new_data);
+size_t (*pre_save_handler)(u8* data, size_t size, u8** new_data);
 
 /* Interesting values, as per config.h */