move hacky code to fuzz_adapter

TokTok · Dec 19, 2021 · 349be5c · 349be5c
1 parent dcaf9f1
commit 349be5c
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Showing 3 changed files with 20 additions and 8 deletions.
diff --git a/testing/fuzzing/fuzz_adapter.c b/testing/fuzzing/fuzz_adapter.c
@@ -1,6 +1,9 @@
 #include "fuzz_adapter.h"
 
 struct fuzz_buf {
+    /* Monotonic counter for time replacement */
+    uint64_t counter;
+    /* Fuzz data buffer */
     const uint8_t *cur;
     const uint8_t *end;
 };
@@ -14,6 +17,7 @@ static struct fuzz_buf data;
 
 void network_adapter_init(const uint8_t* buf, size_t length)
 {
+    data.counter = 0;
     data.cur = buf;
     data.end = buf + length;
 }
@@ -83,3 +87,8 @@ void fuzz_random_bytes(uint8_t *rnd, size_t length)
     memcpy(rnd, data.cur, rd);
     data.cur += rd;
 }
+
+uint64_t fuzz_get_cnt()
+{
+    return data.counter++;
+}
diff --git a/testing/fuzzing/fuzz_adapter.h b/testing/fuzzing/fuzz_adapter.h
@@ -34,9 +34,13 @@ ssize_t fuzz_recvfrom (int __fd, void *__restrict __buf, size_t __n,
 
 ssize_t fuzz_recv (int __fd, void *__buf, size_t __n, int __flags);
 
-/* The followig functions intercept generation of random data */
+/* The following functions intercept generation of random data */
 void fuzz_random_bytes(uint8_t *rnd, size_t length);
 
+/* The following function replaces all time bases with a monotonic counter */
+
+uint64_t fuzz_get_cnt();
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/toxcore/mono_time.c b/toxcore/mono_time.c
@@ -29,6 +29,10 @@
 
 #include "ccompat.h"
 
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+#include "../testing/fuzzing/fuzz_adapter.h"
+#endif
+
 /* don't call into system billions of times for no reason */
 struct Mono_Time {
     uint64_t time;
@@ -97,20 +101,14 @@ static uint64_t current_time_monotonic_default(Mono_Time *mono_time, void *user_
 
 
 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
-static uint64_t fuzz_time = 0;
 static uint64_t current_time_monotonic_dummy(Mono_Time *mono_time, void *user_data)
 {
-    return fuzz_time++;
+    return fuzz_get_cnt();
 }
-
 #endif
 
 Mono_Time *mono_time_new(void)
 {
-#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
-    fuzz_time = 0;
-#endif
-
     Mono_Time *mono_time = (Mono_Time *)malloc(sizeof(Mono_Time));
 
     if (mono_time == nullptr) {
@@ -194,6 +192,7 @@ void mono_time_update(Mono_Time *mono_time)
 uint64_t mono_time_get(const Mono_Time *mono_time)
 {
 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+    // Fuzzing is only single thread for now, no locking needed */
     return mono_time->time;
 #else
     uint64_t time = 0;