Ready to implement JWT signature

esp32_device/main/crypto.c

@@ -224,4 +224,10 @@ char *crypto_encode_base64_safe_url(const char *src, size_t srclen)
         out[olen - 2] = '\0';
 
     return out;
+}
+
+char *crypto_sign_sha256_payload(const char *src, const size_t src_len, size_t *srclen)
+{
+    *srclen = 10;
+    return calloc(1, 10);
 }