J. David Lee
1d3cc1f959
Co-authored-by: jdl <jdl@desktop> Co-authored-by: jdl <jdl@crumpington.com> Reviewed-on: #3
27 lines
769 B
Go
27 lines
769 B
Go
package peer
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import "golang.org/x/crypto/nacl/box"
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type controlCipher struct {
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sharedKey [32]byte
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}
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func newControlCipher(privKey, pubKey []byte) *controlCipher {
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shared := [32]byte{}
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box.Precompute(&shared, (*[32]byte)(pubKey), (*[32]byte)(privKey))
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return &controlCipher{shared}
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}
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func (cc *controlCipher) Encrypt(h header, data, out []byte) []byte {
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const s = controlHeaderSize
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out = out[:s+controlCipherOverhead+len(data)]
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h.Marshal(out[:s])
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box.SealAfterPrecomputation(out[s:s], data, (*[24]byte)(out[:s]), &cc.sharedKey)
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return out
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}
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func (cc *controlCipher) Decrypt(encrypted, out []byte) (data []byte, ok bool) {
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const s = controlHeaderSize
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return box.OpenAfterPrecomputation(out[:0], encrypted[s:], (*[24]byte)(encrypted[:s]), &cc.sharedKey)
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}
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