54 lines
1.0 KiB
Go
54 lines
1.0 KiB
Go
package payload
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import (
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cryptoSHA512 "crypto/sha512"
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"errors"
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"fmt"
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"hash"
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"io"
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)
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type Hash string
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const SHA512 Hash = "sha512"
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func GetHashByHashName(hashName string) (Hash, error) {
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ret := Hash(hashName)
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if _, err := ret.New(); err != nil {
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return "", errors.New("unsupported hash function " + hashName)
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}
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return ret, nil
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}
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func (this Hash) New() (hash.Hash, error) {
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switch this {
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case SHA512:
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return cryptoSHA512.New(), nil
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default:
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msg := fmt.Sprintf("hash '%s' is not supported", this)
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return nil, errors.New(msg)
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}
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}
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func (this Hash) HashOnTheWay(data io.Reader, resultingHash chan []byte) (io.Reader, error) {
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h, err := this.New()
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pipeReader, pipeWriter := io.Pipe()
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if err != nil {
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return nil, err
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}
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go func(resultingHash chan []byte) {
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ou1, ou2 := CopyToTwoWriters(h, pipeWriter, data)
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if ou1.Err != nil {
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panic(ou1.Err)
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}
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if ou2.Err != nil {
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panic(ou2.Err)
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}
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if err := pipeWriter.Close(); err != nil {
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panic(err)
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}
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resultingHash <- h.Sum(nil)
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}(resultingHash)
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return pipeReader, nil
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}
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