// Copyright 2018 Espressif Systems (Shanghai) PTE LTD // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #include <sys/random.h> #include <sys/param.h> #include <assert.h> #include <errno.h> #include <string.h> #include "esp_system.h" #include "esp_log.h" static const char *TAG = "RANDOM"; ssize_t getrandom(void *buf, size_t buflen, unsigned int flags) { // Flags are ignored because: // - esp_random is non-blocking so it works for both blocking and non-blocking calls, // - don't have opportunity so set som other source of entropy. ESP_LOGD(TAG, "getrandom(buf=0x%x, buflen=%d, flags=%u)", (int) buf, buflen, flags); if (buf == NULL) { errno = EFAULT; ESP_LOGD(TAG, "getrandom returns -1 (EFAULT)"); return -1; } esp_fill_random(buf, buflen); ESP_LOGD(TAG, "getrandom returns %d", buflen); return buflen; }