1 // Copyright 2021 The Pigweed Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); you may not 4 // use this file except in compliance with the License. You may obtain a copy of 5 // the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 11 // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 12 // License for the specific language governing permissions and limitations under 13 // the License. 14 15 #pragma once 16 17 #include "pw_bytes/span.h" 18 #include "pw_status/status.h" 19 20 namespace pw::tls_client { 21 // Fill |dest| with fresh, full-entropy random bytes upon each call. 22 // |dest| must contain full entropy. Backend should take care of the possible 23 // conditioning in its implementation. 24 Status GetRandomBytes(ByteSpan dest); 25 26 // An overloaded variant for accomodating C API interfaces, i.e. mbed TLS. GetRandomBytes(std::span<unsigned char> dest)27inline Status GetRandomBytes(std::span<unsigned char> dest) { 28 return GetRandomBytes(std::as_writable_bytes(dest)); 29 } 30 } // namespace pw::tls_client 31