void *CRYPTO_secure_zalloc(size_t num, const char *file, int line)
{
- void *ret = CRYPTO_secure_malloc(num, file, line);
-
- if (ret != NULL)
- memset(ret, 0, num);
- return ret;
+#ifdef IMPLEMENTED
+ if (secure_mem_initialized)
+ /* CRYPTO_secure_malloc() zeroes allocations when it is implemented */
+ return CRYPTO_secure_malloc(num, file, line);
+#endif
+ return CRYPTO_zalloc(num, file, line);
}
void CRYPTO_secure_free(void *ptr, const char *file, int line)
OPENSSL_assert(WITHIN_ARENA(chunk));
+ /* zero the free list header as a precaution against information leakage */
+ memset(chunk, 0, sizeof(SH_LIST));
+
return chunk;
}
list--;
+ /* Zero the higher addressed block's free list pointers */
+ memset(ptr > buddy ? ptr : buddy, 0, sizeof(SH_LIST));
if (ptr > buddy)
ptr = buddy;
#endif
}
+static int test_sec_mem_clear(void)
+{
+#if defined(OPENSSL_SYS_LINUX) || defined(OPENSSL_SYS_UNIX)
+ const int size = 64;
+ unsigned char *p = NULL;
+ int i, res = 0;
+
+ if (!TEST_true(CRYPTO_secure_malloc_init(4096, 32))
+ || !TEST_ptr(p = OPENSSL_secure_malloc(size)))
+ goto err;
+
+ for (i = 0; i < size; i++)
+ if (!TEST_uchar_eq(p[i], 0))
+ goto err;
+
+ for (i = 0; i < size; i++)
+ p[i] = (unsigned char)(i + ' ' + 1);
+
+ OPENSSL_secure_free(p);
+
+ /*
+ * A deliberate use after free here to verify that the memory has been
+ * cleared properly. Since secure free doesn't return the memory to
+ * libc's memory pool, it technically isn't freed. However, the header
+ * bytes have to be skipped and these consist of two pointers in the
+ * current implementation.
+ */
+ for (i = sizeof(void *) * 2; i < size; i++)
+ if (!TEST_uchar_eq(p[i], 0))
+ return 0;
+
+ res = 1;
+ p = NULL;
+
+err:
+ OPENSSL_secure_free(p);
+ CRYPTO_secure_malloc_done();
+ return res;
+#else
+ return 1;
+#endif
+}
+
int setup_tests(void)
{
ADD_TEST(test_sec_mem);
+ ADD_TEST(test_sec_mem_clear);
return 1;
}