github.com/kubiko/snapd@v0.0.0-20201013125620-d4f3094d9ddf/secboot/encrypt.go (about) 1 // -*- Mode: Go; indent-tabs-mode: t -*- 2 3 /* 4 * Copyright (C) 2020 Canonical Ltd 5 * 6 * This program is free software: you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 3 as 8 * published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program. If not, see <http://www.gnu.org/licenses/>. 17 * 18 */ 19 20 package secboot 21 22 import ( 23 "crypto/rand" 24 ) 25 26 const ( 27 // The encryption key size is set so it has the same entropy as the derived 28 // key. 29 encryptionKeySize = 64 30 ) 31 32 // EncryptionKey is the key used to encrypt the data partition. 33 type EncryptionKey [encryptionKeySize]byte 34 35 func NewEncryptionKey() (EncryptionKey, error) { 36 var key EncryptionKey 37 // rand.Read() is protected against short reads 38 _, err := rand.Read(key[:]) 39 // On return, n == len(b) if and only if err == nil 40 return key, err 41 }