Merge pull request #1759 from AFLplusplus/dev

Dev

1 files changed, 424 insertions, 0 deletions

diff --git a/custom_mutators/symqemu/symqemu.c b/custom_mutators/symqemu/symqemu.c
new file mode 100644
index 00000000..73a1640a
--- /dev/null
+++ b/custom_mutators/symqemu/symqemu.c
@@ -0,0 +1,424 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include "config.h"
+#include "debug.h"
+#include "afl-fuzz.h"
+#include "common.h"
+
+afl_state_t *afl_struct;
+static u32   debug = 0;
+static u32   found_items = 0;
+
+#define SYMQEMU_LOCATION "symqemu"
+
+#define DBG(x...) \
+  if (debug) { fprintf(stderr, x); }
+
+typedef struct my_mutator {
+
+  afl_state_t *afl;
+  u32          all;
+  u32          late;
+  u8          *mutator_buf;
+  u8          *out_dir;
+  u8          *target;
+  u8          *symqemu;
+  u8          *input_file;
+  u32          counter;
+  u32          seed;
+  u32          argc;
+  u8         **argv;
+
+} my_mutator_t;
+
+my_mutator_t *afl_custom_init(afl_state_t *afl, unsigned int seed) {
+
+  if (getenv("AFL_DEBUG")) debug = 1;
+
+  my_mutator_t *data = calloc(1, sizeof(my_mutator_t));
+  if (!data) {
+
+    perror("afl_custom_init alloc");
+    return NULL;
+
+  }
+
+  char *path = getenv("PATH");
+  char *exec_name = "symqemu-x86_64";
+  char *token = strtok(path, ":");
+  char  exec_path[4096];
+
+  while (token != NULL && data->symqemu == NULL) {
+
+    snprintf(exec_path, sizeof(exec_path), "%s/%s", token, exec_name);
+    if (access(exec_path, X_OK) == 0) {
+
+      data->symqemu = (u8 *)strdup(exec_path);
+      break;
+
+    }
+
+    token = strtok(NULL, ":");
+
+  }
+
+  if (!data->symqemu) FATAL("symqemu binary %s not found", exec_name);
+  DBG("Found %s\n", data->symqemu);
+
+  if (getenv("AFL_CUSTOM_MUTATOR_ONLY")) {
+
+    WARNF(
+        "the symqemu module is not very effective with "
+        "AFL_CUSTOM_MUTATOR_ONLY.");
+
+  }
+
+  if ((data->mutator_buf = malloc(MAX_FILE)) == NULL) {
+
+    free(data);
+    perror("mutator_buf alloc");
+    return NULL;
+
+  }
+
+  data->target = getenv("AFL_CUSTOM_INFO_PROGRAM");
+
+  u8 *path_tmp = getenv("AFL_CUSTOM_INFO_OUT");
+  u32 len = strlen(path_tmp) + 32;
+  u8 *symqemu_path = malloc(len);
+  data->out_dir = malloc(len);
+  snprintf(symqemu_path, len, "%s/%s", path_tmp, SYMQEMU_LOCATION);
+  snprintf(data->out_dir, len, "%s/out", symqemu_path, path_tmp);
+
+  (void)mkdir(symqemu_path, 0755);
+  (void)mkdir(data->out_dir, 0755);
+
+  setenv("SYMCC_OUTPUT_DIR", data->out_dir, 1);
+
+  data->input_file = getenv("AFL_CUSTOM_INFO_PROGRAM_INPUT");
+
+  u8 *tmp = NULL;
+  if ((tmp = getenv("AFL_CUSTOM_INFO_PROGRAM_ARGV")) && *tmp) {
+
+    int argc = 0, index = 2;
+    for (u32 i = 0; i < strlen(tmp); ++i)
+      if (isspace(tmp[i])) ++argc;
+
+    data->argv = (u8 **)malloc((argc + 4) * sizeof(u8 **));
+    u8 *p = strdup(tmp);
+
+    do {
+
+      data->argv[index] = p;
+      while (*p && !isspace(*p))
+        ++p;
+      if (*p) {
+
+        *p++ = 0;
+        while (isspace(*p))
+          ++p;
+
+      }
+
+      if (strcmp(data->argv[index], "@@") == 0) {
+
+        if (!data->input_file) {
+
+          u32 ilen = strlen(symqemu_path) + 32;
+          data->input_file = malloc(ilen);
+          snprintf(data->input_file, ilen, "%s/.input", symqemu_path);
+
+        }
+
+        data->argv[index] = data->input_file;
+
+      }
+
+      DBG("%d: %s\n", index, data->argv[index]);
+      index++;
+
+    } while (*p);
+
+    data->argv[index] = NULL;
+    data->argc = index;
+
+  } else {
+
+    data->argv = (u8 **)malloc(8 * sizeof(u8 **));
+    data->argc = 2;
+    data->argv[2] = NULL;
+
+  }
+
+  data->argv[0] = data->symqemu;
+  data->argv[1] = data->target;
+  data->afl = afl;
+  data->seed = seed;
+  afl_struct = afl;
+
+  if (getenv("SYMQEMU_ALL")) { data->all = 1; }
+  if (getenv("SYMQEMU_LATE")) { data->late = 1; }
+  if (data->input_file) { setenv("SYMCC_INPUT_FILE", data->input_file, 1); }
+
+  DBG("out_dir=%s, target=%s, input_file=%s, argc=%u\n", data->out_dir,
+      data->target,
+      data->input_file ? (char *)data->input_file : (char *)"<stdin>",
+      data->argc);
+
+  if (debug) {
+
+    fprintf(stderr, "[");
+    for (u32 i = 0; i <= data->argc; ++i)
+      fprintf(stderr, " \"%s\"",
+              data->argv[i] ? (char *)data->argv[i] : "<NULL>");
+    fprintf(stderr, " ]\n");
+
+  }
+
+  return data;
+
+}
+
+/* No need to receive a splicing item */
+void afl_custom_splice_optout(void *data) {
+
+  (void)(data);
+
+}
+
+/* Get unix time in milliseconds */
+
+inline u64 get_cur_time(void) {
+
+  struct timeval  tv;
+  struct timezone tz;
+
+  gettimeofday(&tv, &tz);
+
+  return (tv.tv_sec * 1000ULL) + (tv.tv_usec / 1000);
+
+}
+
+u32 afl_custom_fuzz_count(my_mutator_t *data, const u8 *buf, size_t buf_size) {
+
+  if (likely((!afl_struct->queue_cur->favored && !data->all) ||
+             afl_struct->queue_cur->was_fuzzed)) {
+
+    return 0;
+
+  }
+
+  if (likely(data->late)) {
+
+    if (unlikely(get_cur_time() - afl_struct->last_find_time <=
+                 10 * 60 * 1000)) {
+
+      return 0;
+
+    }
+
+  }
+
+  int         pipefd[2];
+  struct stat st;
+
+  if (afl_struct->afl_env.afl_no_ui) {
+
+    ACTF("Sending to symqemu: %s", afl_struct->queue_cur->fname);
+
+  }
+
+  if (!(stat(afl_struct->queue_cur->fname, &st) == 0 && S_ISREG(st.st_mode) &&
+        st.st_size)) {
+
+    PFATAL("Couldn't find enqueued file: %s", afl_struct->queue_cur->fname);
+
+  }
+
+  if (afl_struct->fsrv.use_stdin) {
+
+    if (pipe(pipefd) == -1) {
+
+      PFATAL(
+          "Couldn't create a pipe for interacting with symqemu child process");
+
+    }
+
+  }
+
+  if (data->input_file) {
+
+    int     fd = open(data->input_file, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+    ssize_t s = write(fd, buf, buf_size);
+    close(fd);
+    DBG("wrote %zd/%zd to %s\n", s, buf_size, data->input_file);
+
+  }
+
+  int pid = fork();
+
+  if (pid == -1) return 0;
+
+  if (likely(pid)) {
+
+    if (!data->input_file || afl_struct->fsrv.use_stdin) {
+
+      close(pipefd[0]);
+
+      if (fcntl(pipefd[1], F_GETPIPE_SZ)) {
+
+        fcntl(pipefd[1], F_SETPIPE_SZ, MAX_FILE);
+
+      }
+
+      ck_write(pipefd[1], buf, buf_size, data->input_file);
+
+      close(pipefd[1]);
+
+    }
+
+    pid = waitpid(pid, NULL, 0);
+    DBG("symqemu finished executing!\n");
+
+  } else /* (pid == 0) */ {  // child
+
+    if (afl_struct->fsrv.use_stdin) {
+
+      close(pipefd[1]);
+      dup2(pipefd[0], 0);
+
+    }
+
+    DBG("exec=%s\n", data->target);
+    if (!debug) {
+
+      close(1);
+      close(2);
+      dup2(afl_struct->fsrv.dev_null_fd, 1);
+      dup2(afl_struct->fsrv.dev_null_fd, 2);
+
+    }
+
+    execvp((char *)data->argv[0], (char **)data->argv);
+    fprintf(stderr, "Executing: [");
+    for (u32 i = 0; i <= data->argc; ++i)
+      fprintf(stderr, " \"%s\"",
+              data->argv[i] ? (char *)data->argv[i] : "<NULL>");
+    fprintf(stderr, " ]\n");
+    FATAL("Failed to execute %s %s\n", data->argv[0], data->argv[1]);
+    exit(-1);
+
+  }
+
+  /* back in mother process */
+
+  struct dirent **nl;
+  s32             i, items = scandir(data->out_dir, &nl, NULL, NULL);
+  found_items = 0;
+  char source_name[4096];
+
+  if (items > 0) {
+
+    for (i = 0; i < (u32)items; ++i) {
+
+      // symqemu output files start with a digit
+      if (!isdigit(nl[i]->d_name[0])) continue;
+
+      struct stat st;
+      snprintf(source_name, sizeof(source_name), "%s/%s", data->out_dir,
+               nl[i]->d_name);
+      DBG("file=%s\n", source_name);
+
+      if (stat(source_name, &st) == 0 && S_ISREG(st.st_mode) && st.st_size) {
+
+        ++found_items;
+
+      }
+
+      free(nl[i]);
+
+    }
+
+    free(nl);
+
+  }
+
+  DBG("Done, found %u items!\n", found_items);
+
+  return found_items;
+
+}
+
+size_t afl_custom_fuzz(my_mutator_t *data, u8 *buf, size_t buf_size,
+                       u8 **out_buf, u8 *add_buf, size_t add_buf_size,
+                       size_t max_size) {
+
+  struct dirent **nl;
+  s32             done = 0, i, items = scandir(data->out_dir, &nl, NULL, NULL);
+  char            source_name[4096];
+
+  if (items > 0) {
+
+    for (i = 0; i < (u32)items; ++i) {
+
+      // symqemu output files start with a digit
+      if (!isdigit(nl[i]->d_name[0])) continue;
+
+      struct stat st;
+      snprintf(source_name, sizeof(source_name), "%s/%s", data->out_dir,
+               nl[i]->d_name);
+      DBG("file=%s\n", source_name);
+
+      if (stat(source_name, &st) == 0 && S_ISREG(st.st_mode) && st.st_size) {
+
+        int fd = open(source_name, O_RDONLY);
+        if (fd < 0) { goto got_an_issue; }
+
+        ssize_t r = read(fd, data->mutator_buf, MAX_FILE);
+        close(fd);
+
+        DBG("fn=%s, fd=%d, size=%ld\n", source_name, fd, r);
+
+        if (r < 1) { goto got_an_issue; }
+
+        done = 1;
+        --found_items;
+        unlink(source_name);
+
+        *out_buf = data->mutator_buf;
+        return (u32)r;
+
+      }
+
+      free(nl[i]);
+
+    }
+
+    free(nl);
+
+  }
+
+got_an_issue:
+  *out_buf = NULL;
+  return 0;
+
+}
+
+/**
+ * Deinitialize everything
+ *
+ * @param data The data ptr from afl_custom_init
+ */
+void afl_custom_deinit(my_mutator_t *data) {
+
+  free(data->mutator_buf);
+  free(data);
+
+}
+