1*e7b1675dSTing-Kang Chang// Copyright 2022 Google LLC 2*e7b1675dSTing-Kang Chang// 3*e7b1675dSTing-Kang Chang// Licensed under the Apache License, Version 2.0 (the "License"); 4*e7b1675dSTing-Kang Chang// you may not use this file except in compliance with the License. 5*e7b1675dSTing-Kang Chang// You may obtain a copy of the License at 6*e7b1675dSTing-Kang Chang// 7*e7b1675dSTing-Kang Chang// http://www.apache.org/licenses/LICENSE-2.0 8*e7b1675dSTing-Kang Chang// 9*e7b1675dSTing-Kang Chang// Unless required by applicable law or agreed to in writing, software 10*e7b1675dSTing-Kang Chang// distributed under the License is distributed on an "AS IS" BASIS, 11*e7b1675dSTing-Kang Chang// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12*e7b1675dSTing-Kang Chang// See the License for the specific language governing permissions and 13*e7b1675dSTing-Kang Chang// limitations under the License. 14*e7b1675dSTing-Kang Chang// 15*e7b1675dSTing-Kang Chang//////////////////////////////////////////////////////////////////////////////// 16*e7b1675dSTing-Kang Chang 17*e7b1675dSTing-Kang Chang// Package aead provides internal implementations of the AEAD primitive. 18*e7b1675dSTing-Kang Changpackage aead 19*e7b1675dSTing-Kang Chang 20*e7b1675dSTing-Kang Changimport "fmt" 21*e7b1675dSTing-Kang Chang 22*e7b1675dSTing-Kang Changconst ( 23*e7b1675dSTing-Kang Chang // AESGCMIVSize is the acceptable IV size defined by RFC 5116. 24*e7b1675dSTing-Kang Chang AESGCMIVSize = 12 25*e7b1675dSTing-Kang Chang // AESGCMTagSize is the acceptable tag size defined by RFC 5116. 26*e7b1675dSTing-Kang Chang AESGCMTagSize = 16 27*e7b1675dSTing-Kang Chang) 28*e7b1675dSTing-Kang Chang 29*e7b1675dSTing-Kang Chang// ValidateAESKeySize checks if the given key size is a valid AES key size. 30*e7b1675dSTing-Kang Changfunc ValidateAESKeySize(sizeInBytes uint32) error { 31*e7b1675dSTing-Kang Chang switch sizeInBytes { 32*e7b1675dSTing-Kang Chang case 16, 32: 33*e7b1675dSTing-Kang Chang return nil 34*e7b1675dSTing-Kang Chang default: 35*e7b1675dSTing-Kang Chang return fmt.Errorf("invalid AES key size; want 16 or 32, got %d", sizeInBytes) 36*e7b1675dSTing-Kang Chang } 37*e7b1675dSTing-Kang Chang} 38