func (tree *MerkleTree) lookup(root *node, indexBytes []byte) (value []byte, trace *proto.TreeProof, err error) {
trace = &proto.TreeProof{}
var tracingRoot coname.MerkleNode = makeTracingNode(tree, trace, root)
value, err = coname.TreeLookup(tracingRoot, indexBytes)
if err != nil {
return nil, nil, err
}
return
}
func verifyProof(s *Snapshot, index, value []byte, proof *proto.TreeProof) {
reconstructed, err := coname.ReconstructTree(proof, coname.ToBits(coname.IndexBits, index))
if err != nil {
panic(err)
}
redoneLookup, err := coname.TreeLookup(reconstructed, index)
if err != nil {
panic(err)
}
if got, want := redoneLookup, value; !bytes.Equal(got, want) {
log.Panicf("reconstructed lookup got different result: %v rather than %v", got, want)
}
recomputedHash, err := coname.RecomputeHash(treeNonce, reconstructed)
if err != nil {
panic(err)
}
rootHash, err := s.GetRootHash()
if err != nil {
panic(err)
}
if got, want := recomputedHash, rootHash; !bytes.Equal(got, want) {
log.Panicf("reconstructed hash differed: %x rather than %x", got, want)
}
}