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Diffstat (limited to 'examples/custom_mutators/post_library_png.so.c')
-rw-r--r--examples/custom_mutators/post_library_png.so.c163
1 files changed, 0 insertions, 163 deletions
diff --git a/examples/custom_mutators/post_library_png.so.c b/examples/custom_mutators/post_library_png.so.c
deleted file mode 100644
index 941f7e55..00000000
--- a/examples/custom_mutators/post_library_png.so.c
+++ /dev/null
@@ -1,163 +0,0 @@
-/*
-   american fuzzy lop++ - postprocessor for PNG
-   ------------------------------------------
-
-   Originally written by Michal Zalewski
-
-   Copyright 2015 Google Inc. All rights reserved.
-   Adapted to the new API, 2020 by Dominik Maier
-
-   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
-
-   See post_library.so.c for a general discussion of how to implement
-   postprocessors. This specific postprocessor attempts to fix up PNG
-   checksums, providing a slightly more complicated example than found
-   in post_library.so.c.
-
-   Compile with:
-
-     gcc -shared -Wall -O3 post_library_png.so.c -o post_library_png.so -lz
-
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdint.h>
-#include <string.h>
-#include <zlib.h>
-
-#include <arpa/inet.h>
-
-/* A macro to round an integer up to 4 kB. */
-
-#define UP4K(_i) ((((_i) >> 12) + 1) << 12)
-
-typedef struct post_state {
-
-  unsigned char *buf;
-  size_t         size;
-
-} post_state_t;
-
-void *afl_custom_init(void *afl) {
-
-  post_state_t *state = malloc(sizeof(post_state_t));
-  if (!state) {
-
-    perror("malloc");
-    return NULL;
-
-  }
-
-  state->buf = calloc(sizeof(unsigned char), 4096);
-  if (!state->buf) {
-
-    free(state);
-    perror("calloc");
-    return NULL;
-
-  }
-
-  return state;
-
-}
-
-size_t afl_custom_post_process(post_state_t *data, const unsigned char *in_buf,
-                               unsigned int          len,
-                               const unsigned char **out_buf) {
-
-  unsigned char *new_buf = (unsigned char *)in_buf;
-  unsigned int   pos = 8;
-
-  /* Don't do anything if there's not enough room for the PNG header
-     (8 bytes). */
-
-  if (len < 8) {
-
-    *out_buf = in_buf;
-    return len;
-
-  }
-
-  /* Minimum size of a zero-length PNG chunk is 12 bytes; if we
-     don't have that, we can bail out. */
-
-  while (pos + 12 <= len) {
-
-    unsigned int chunk_len, real_cksum, file_cksum;
-
-    /* Chunk length is the first big-endian dword in the chunk. */
-
-    chunk_len = ntohl(*(uint32_t *)(in_buf + pos));
-
-    /* Bail out if chunk size is too big or goes past EOF. */
-
-    if (chunk_len > 1024 * 1024 || pos + 12 + chunk_len > len) break;
-
-    /* Chunk checksum is calculated for chunk ID (dword) and the actual
-       payload. */
-
-    real_cksum = htonl(crc32(0, in_buf + pos + 4, chunk_len + 4));
-
-    /* The in-file checksum is the last dword past the chunk data. */
-
-    file_cksum = *(uint32_t *)(in_buf + pos + 8 + chunk_len);
-
-    /* If the checksums do not match, we need to fix the file. */
-
-    if (real_cksum != file_cksum) {
-
-      /* First modification? Make a copy of the input buffer. Round size
-         up to 4 kB to minimize the number of reallocs needed. */
-
-      if (new_buf == in_buf) {
-
-        if (len <= data->size) {
-
-          new_buf = data->buf;
-
-        } else {
-
-          new_buf = realloc(data->buf, UP4K(len));
-          if (!new_buf) {
-
-            *out_buf = in_buf;
-            return len;
-
-          }
-
-          data->buf = new_buf;
-          data->size = UP4K(len);
-          memcpy(new_buf, in_buf, len);
-
-        }
-
-      }
-
-      *(uint32_t *)(new_buf + pos + 8 + chunk_len) = real_cksum;
-
-    }
-
-    /* Skip the entire chunk and move to the next one. */
-
-    pos += 12 + chunk_len;
-
-  }
-
-  *out_buf = new_buf;
-  return len;
-
-}
-
-/* Gets called afterwards */
-void afl_custom_deinit(post_state_t *data) {
-
-  free(data->buf);
-  free(data);
-
-}
-