56 lines
1.4 KiB
Go
56 lines
1.4 KiB
Go
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.
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// It 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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// MakePreimage returns a new Preimage from a bytes slice. An error is returned
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// if the number of bytes passed in is not PreimageSize.
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func MakePreimage(newPreimage []byte) (Preimage, error) {
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nhlen := len(newPreimage)
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if nhlen != PreimageSize {
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return Preimage{}, fmt.Errorf("invalid preimage length of %v, "+
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"want %v", 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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// MakePreimageFromStr creates a Preimage from a hex preimage string.
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func MakePreimageFromStr(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 Preimage{}, fmt.Errorf("invalid preimage string length "+
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"of %v, 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 Preimage{}, err
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}
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return MakePreimage(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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