Introduce wolfCrypt_Init warmup, NO_WOLFSSL_WARMUP

Author: gojimmypi

.wolfssl_known_macro_extras

@@ -437,6 +437,7 @@ NO_WOLFSSL_SHA512_INTERLEAVE
 NO_WOLFSSL_SKIP_TRAILING_PAD
 NO_WOLFSSL_SMALL_STACK_STATIC
 NO_WOLFSSL_USE_ASM_CERT
+NO_WOLFSSL_WARMUP
 NO_WOLFSSL_XILINX_TAG_MALLOC
 NRF52
 NRF52_SERIES

wolfcrypt/src/wc_port.c

@@ -150,6 +150,10 @@
 #endif
 #endif
 
+#if !defined(NO_AES) && !defined(WC_NO_AES)
+    #include <wolfssl/wolfcrypt/aes.h>
+#endif
+
 /* prevent multiple mutex initializations */
 static volatile int initRefCount = 0;
 
@@ -167,6 +171,53 @@ int wolfCrypt_Init(void)
     if (initRefCount == 0) {
         WOLFSSL_ENTER("wolfCrypt_Init");
 
+    /* */
+    #ifndef NO_WOLFSSL_WARMUP
+        /* Warm up the hardware to allocate any heap semaphore early */
+
+        WC_RNG rng;
+        byte dummy;
+
+    #if !defined(NO_AES) && !defined(WC_NO_AES)
+        Aes aes;
+        unsigned char key16[16];
+        unsigned char iv[12];
+        unsigned char in[16];
+        unsigned char out[16];
+        unsigned char tag[16];
+        int devId;
+    #endif
+
+    #if defined(DEBUG_WOLFSSL_MALLOC_VERBOSE)
+        WOLFSSL_MSG("Warming up RNG");
+    #endif
+
+        if (wc_InitRng(&rng) == 0) {
+            (void)wc_RNG_GenerateBlock(&rng, &dummy, 1);  /* forces Hash_DRBG/SHA */
+            wc_FreeRng(&rng);
+        }
+
+    #if !defined(NO_AES) && !defined(WC_NO_AES)
+    #if defined(DEBUG_WOLFSSL_MALLOC_VERBOSE)
+        WOLFSSL_MSG("Warming up RNG");
+    #endif
+        memset(key16, 0, sizeof(key16));
+        memset(iv, 0, sizeof(iv));
+        memset(in, 0, sizeof(in));
+        devId = INVALID_DEVID;
+
+        ret = wc_AesInit(&aes, NULL, devId);
+        if (ret != 0) return ret;
+        ret = wc_AesGcmSetKey(&aes, key16, sizeof(key16));
+        if (ret != 0) { wc_AesFree(&aes); return ret; }
+        ret = wc_AesGcmEncrypt(&aes, out, in, (word32)sizeof(in),
+                                iv, (word32)sizeof(iv),
+                                tag, (word32)sizeof(tag),
+                                NULL, 0);
+        wc_AesFree(&aes);
+    #endif /* !NO_AES && !WC_NO_AES */
+    #endif /* NO_WOLFSSL_WARMUP */
+
     #if defined(__aarch64__) && defined(WOLFSSL_ARMASM_BARRIER_DETECT)
         aarch64_use_sb = IS_AARCH64_SB(cpuid_get_flags());
     #endif
@@ -444,11 +495,13 @@ int wolfCrypt_Init(void)
             return ret;
         }
 #endif
-    }
+
+    } /* (initRefCount == 0) */
+
     initRefCount++;
 
     return ret;
-}
+} /* wolfCrypt_Init */
 
 #if defined(WOLFSSL_TRACK_MEMORY_VERBOSE) && !defined(WOLFSSL_STATIC_MEMORY)
 long wolfCrypt_heap_peakAllocs_checkpoint(void) {