56 lines
1.4 KiB
Go
56 lines
1.4 KiB
Go
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package lntypes
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import (
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"crypto/sha256"
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"encoding/hex"
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"fmt"
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)
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// PreimageSize of array used to store preimagees.
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const PreimageSize = 32
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// Preimage is used in several of the lightning messages and common structures. It
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// represents a payment preimage.
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type Preimage [PreimageSize]byte
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// String returns the Preimage as a hexadecimal string.
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func (p Preimage) String() string {
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return hex.EncodeToString(p[:])
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}
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// NewPreimage returns a new Preimage from a byte slice. An error is returned if
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// the number of bytes passed in is not PreimageSize.
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func NewPreimage(newPreimage []byte) (*Preimage, error) {
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nhlen := len(newPreimage)
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if nhlen != PreimageSize {
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return nil, fmt.Errorf("invalid preimage length of %v, want %v",
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nhlen, PreimageSize)
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}
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var preimage Preimage
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copy(preimage[:], newPreimage)
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return &preimage, nil
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}
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// NewPreimageFromStr creates a Preimage from a hex preimage string.
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func NewPreimageFromStr(newPreimage string) (*Preimage, error) {
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// Return error if preimage string is of incorrect length.
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if len(newPreimage) != PreimageSize*2 {
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return nil, fmt.Errorf("invalid preimage string length of %v, "+
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"want %v", len(newPreimage), PreimageSize*2)
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}
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preimage, err := hex.DecodeString(newPreimage)
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if err != nil {
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return nil, err
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}
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return NewPreimage(preimage)
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}
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// Hash returns the sha256 hash of the preimage.
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func (p *Preimage) Hash() Hash {
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return Hash(sha256.Sum256(p[:]))
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}
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