65 lines
1.4 KiB
Go
65 lines
1.4 KiB
Go
// Copyright (C) 2022 Opsmate, Inc.
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//
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// This Source Code Form is subject to the terms of the Mozilla
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// Public License, v. 2.0. If a copy of the MPL was not distributed
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// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
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//
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// This software is distributed WITHOUT A WARRANTY OF ANY KIND.
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// See the Mozilla Public License for details.
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package merkletree
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import (
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"crypto/sha256"
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"encoding/base64"
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"encoding/json"
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"fmt"
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)
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const HashLen = 32
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type Hash [HashLen]byte
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func (h Hash) Base64String() string {
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return base64.StdEncoding.EncodeToString(h[:])
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}
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func (h Hash) MarshalJSON() ([]byte, error) {
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return json.Marshal(h[:])
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}
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func (h *Hash) UnmarshalJSON(b []byte) error {
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var hashBytes []byte
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if err := json.Unmarshal(b, &hashBytes); err != nil {
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return err
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}
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if len(hashBytes) != HashLen {
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return fmt.Errorf("Merkle Tree hash has wrong length (should be %d bytes long, not %d)", HashLen)
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}
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copy(h[:], hashBytes)
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return nil
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}
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func HashNothing() Hash {
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return sha256.Sum256(nil)
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}
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func HashLeaf(leafBytes []byte) Hash {
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var hash Hash
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hasher := sha256.New()
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hasher.Write([]byte{0x00})
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hasher.Write(leafBytes)
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hasher.Sum(hash[:0])
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return hash
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}
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func HashChildren(left Hash, right Hash) Hash {
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var hash Hash
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hasher := sha256.New()
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hasher.Write([]byte{0x01})
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hasher.Write(left[:])
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hasher.Write(right[:])
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hasher.Sum(hash[:0])
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return hash
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}
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