32 lines
672 B
Go
32 lines
672 B
Go
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package scrypto
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import (
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"bytes"
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"fmt"
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)
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func PadPKCS5(data []byte, blockSize int) []byte {
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paddingSize := blockSize - len(data)%blockSize
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padding := bytes.Repeat([]byte{byte(paddingSize)}, paddingSize)
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return append(data, padding...)
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}
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func UnpadPKCS5(data []byte, blockSize int) ([]byte, error) {
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dataSize := len(data)
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if dataSize%blockSize != 0 {
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return nil, fmt.Errorf("truncated data")
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}
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if len(data) == 0 {
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return data, nil
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} else {
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paddingSize := int(data[dataSize-1])
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if paddingSize > dataSize || paddingSize > blockSize {
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return nil, fmt.Errorf("invalid padding size %d", paddingSize)
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}
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return data[:dataSize-paddingSize], nil
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}
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}
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