added -N no_unlink option

3 files changed, 41 insertions, 9 deletions

diff --git a/src/afl-fuzz-globals.c b/src/afl-fuzz-globals.c
index 5c36eb0b..de716098 100644
--- a/src/afl-fuzz-globals.c
+++ b/src/afl-fuzz-globals.c
@@ -83,7 +83,9 @@ u32 hang_tmout = EXEC_TIMEOUT;          /* Timeout used for hang det (ms)   */
 u64 mem_limit = MEM_LIMIT;              /* Memory cap for child (MB)        */
 
 u8 cal_cycles = CAL_CYCLES,             /* Calibration cycles defaults      */
-    cal_cycles_long = CAL_CYCLES_LONG, debug,                 /* Debug mode */
+    cal_cycles_long = CAL_CYCLES_LONG,  /* Calibration cycles defaults      */
+    debug,                              /* Debug mode                       */
+    no_unlink,                          /* do not unlink cur_input          */
     custom_only,                        /* Custom mutator only mode         */
     python_only;                        /* Python-only mode                 */
 
diff --git a/src/afl-fuzz-run.c b/src/afl-fuzz-run.c
index 8fa91afd..8f72d0fe 100644
--- a/src/afl-fuzz-run.c
+++ b/src/afl-fuzz-run.c
@@ -288,9 +288,16 @@ void write_to_testcase(void* mem, u32 len) {
 
   if (out_file) {
 
-    unlink(out_file);                                     /* Ignore errors. */
+    if (no_unlink) {
 
-    fd = open(out_file, O_WRONLY | O_CREAT | O_EXCL, 0600);
+      fd = open(out_file, O_WRONLY | O_CREAT | O_TRUNC, 0600);
+
+    } else {
+
+      unlink(out_file);                                   /* Ignore errors. */
+      fd = open(out_file, O_WRONLY | O_CREAT | O_EXCL, 0600);
+
+    }
 
     if (fd < 0) PFATAL("Unable to create '%s'", out_file);
 
@@ -330,9 +337,16 @@ void write_with_gap(void* mem, u32 len, u32 skip_at, u32 skip_len) {
 
   if (out_file) {
 
-    unlink(out_file);                                     /* Ignore errors. */
+    if (no_unlink) {
+
+      fd = open(out_file, O_WRONLY | O_CREAT | O_TRUNC, 0600);
+
+    } else {
 
-    fd = open(out_file, O_WRONLY | O_CREAT | O_EXCL, 0600);
+      unlink(out_file);                                   /* Ignore errors. */
+      fd = open(out_file, O_WRONLY | O_CREAT | O_EXCL, 0600);
+
+    }
 
     if (fd < 0) PFATAL("Unable to create '%s'", out_file);
 
@@ -760,9 +774,16 @@ u8 trim_case(char** argv, struct queue_entry* q, u8* in_buf) {
 
     s32 fd;
 
-    unlink(q->fname);                                      /* ignore errors */
+    if (no_unlink) {
+
+      fd = open(q->fname, O_WRONLY | O_CREAT | O_TRUNC, 0600);
 
-    fd = open(q->fname, O_WRONLY | O_CREAT | O_EXCL, 0600);
+    } else {
+
+      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);
 
diff --git a/src/afl-fuzz.c b/src/afl-fuzz.c
index bdbc48e0..3a5b0b4e 100644
--- a/src/afl-fuzz.c
+++ b/src/afl-fuzz.c
@@ -122,9 +122,11 @@ static void usage(u8* argv0) {
       "                  a recommended value is 10-60. see docs/README.MOpt\n\n"
 
       "Fuzzing behavior settings:\n"
+      "  -N            - do not unlink the fuzzing input file\n"
       "  -d            - quick & dirty mode (skips deterministic steps)\n"
       "  -n            - fuzz without instrumentation (dumb mode)\n"
-      "  -x dir        - optional fuzzer dictionary (see README)\n\n"
+      "  -x dir        - optional fuzzer dictionary (see README, its really "
+      "good!)\n\n"
 
       "Testing settings:\n"
       "  -s seed       - use a fixed seed for the RNG\n"
@@ -195,7 +197,7 @@ int main(int argc, char** argv) {
   init_seed = tv.tv_sec ^ tv.tv_usec ^ getpid();
 
   while ((opt = getopt(argc, argv,
-                       "+i:I:o:f:m:t:T:dnCB:S:M:x:QUWe:p:s:V:E:L:hR")) > 0)
+                       "+i:I:o:f:m:t:T:dnCB:S:M:x:QNUWe:p:s:V:E:L:hR")) > 0)
 
     switch (opt) {
 
@@ -426,6 +428,13 @@ int main(int argc, char** argv) {
 
         break;
 
+      case 'N':                                             /* Unicorn mode */
+
+        if (no_unlink) FATAL("Multiple -N options not supported");
+        no_unlink = 1;
+
+        break;
+
       case 'U':                                             /* Unicorn mode */
 
         if (unicorn_mode) FATAL("Multiple -U options not supported");