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(span<unsigned char> dest)27 inline Status GetRandomBytes(span<unsigned char> dest) {
28 return GetRandomBytes(as_writable_bytes(dest));
29 }
30 } // namespace pw::tls_client
31