Copy certifiers from light-client

certifiers/helper.go

@@ -0,0 +1,149 @@
+package certifiers
+
+import (
+	"time"
+
+	crypto "github.com/tendermint/go-crypto"
+
+	"github.com/tendermint/tendermint/types"
+)
+
+// ValKeys is a helper for testing.
+//
+// It lets us simulate signing with many keys, either ed25519 or secp256k1.
+// The main use case is to create a set, and call GenCommit
+// to get propely signed header for testing.
+//
+// You can set different weights of validators each time you call
+// ToValidators, and can optionally extend the validator set later
+// with Extend or ExtendSecp
+type ValKeys []crypto.PrivKey
+
+// GenValKeys produces an array of private keys to generate commits
+func GenValKeys(n int) ValKeys {
+	res := make(ValKeys, n)
+	for i := range res {
+		res[i] = crypto.GenPrivKeyEd25519().Wrap()
+	}
+	return res
+}
+
+// Change replaces the key at index i
+func (v ValKeys) Change(i int) ValKeys {
+	res := make(ValKeys, len(v))
+	copy(res, v)
+	res[i] = crypto.GenPrivKeyEd25519().Wrap()
+	return res
+}
+
+// Extend adds n more keys (to remove, just take a slice)
+func (v ValKeys) Extend(n int) ValKeys {
+	extra := GenValKeys(n)
+	return append(v, extra...)
+}
+
+// GenSecpValKeys produces an array of secp256k1 private keys to generate commits
+func GenSecpValKeys(n int) ValKeys {
+	res := make(ValKeys, n)
+	for i := range res {
+		res[i] = crypto.GenPrivKeySecp256k1().Wrap()
+	}
+	return res
+}
+
+// ExtendSecp adds n more secp256k1 keys (to remove, just take a slice)
+func (v ValKeys) ExtendSecp(n int) ValKeys {
+	extra := GenSecpValKeys(n)
+	return append(v, extra...)
+}
+
+// ToValidators produces a list of validators from the set of keys
+// The first key has weight `init` and it increases by `inc` every step
+// so we can have all the same weight, or a simple linear distribution
+// (should be enough for testing)
+func (v ValKeys) ToValidators(init, inc int64) *types.ValidatorSet {
+	res := make([]*types.Validator, len(v))
+	for i, k := range v {
+		res[i] = types.NewValidator(k.PubKey(), init+int64(i)*inc)
+	}
+	return types.NewValidatorSet(res)
+}
+
+// signHeader properly signs the header with all keys from first to last exclusive
+func (v ValKeys) signHeader(header *types.Header, first, last int) *types.Commit {
+	votes := make([]*types.Vote, len(v))
+
+	// we need this list to keep the ordering...
+	vset := v.ToValidators(1, 0)
+
+	// fill in the votes we want
+	for i := first; i < last; i++ {
+		vote := makeVote(header, vset, v[i])
+		votes[vote.ValidatorIndex] = vote
+	}
+
+	res := &types.Commit{
+		BlockID:    types.BlockID{Hash: header.Hash()},
+		Precommits: votes,
+	}
+	return res
+}
+
+func makeVote(header *types.Header, vals *types.ValidatorSet, key crypto.PrivKey) *types.Vote {
+	addr := key.PubKey().Address()
+	idx, _ := vals.GetByAddress(addr)
+	vote := &types.Vote{
+		ValidatorAddress: addr,
+		ValidatorIndex:   idx,
+		Height:           header.Height,
+		Round:            1,
+		Type:             types.VoteTypePrecommit,
+		BlockID:          types.BlockID{Hash: header.Hash()},
+	}
+	// Sign it
+	signBytes := types.SignBytes(header.ChainID, vote)
+	vote.Signature = key.Sign(signBytes)
+	return vote
+}
+
+func genHeader(chainID string, height int, txs types.Txs,
+	vals *types.ValidatorSet, appHash []byte) *types.Header {
+
+	return &types.Header{
+		ChainID: chainID,
+		Height:  height,
+		Time:    time.Now(),
+		NumTxs:  len(txs),
+		// LastBlockID
+		// LastCommitHash
+		ValidatorsHash: vals.Hash(),
+		DataHash:       txs.Hash(),
+		AppHash:        appHash,
+	}
+}
+
+// GenCommit calls genHeader and signHeader and combines them into a *Commit
+func (v ValKeys) GenCommit(chainID string, height int, txs types.Txs,
+	vals *types.ValidatorSet, appHash []byte, first, last int) *Commit {
+
+	header := genHeader(chainID, height, txs, vals, appHash)
+	check := &Commit{
+		Header:          header,
+		Commit:          v.signHeader(header, first, last),
+		CanonicalCommit: true,
+	}
+	return check
+}
+
+// GenFullCommit calls genHeader and signHeader and combines them into a *Commit
+func (v ValKeys) GenFullCommit(chainID string, height int, txs types.Txs,
+	vals *types.ValidatorSet, appHash []byte, first, last int) FullCommit {
+
+	header := genHeader(chainID, height, txs, vals, appHash)
+	commit := &Commit{
+		Header:          header,
+		Commit:          v.signHeader(header, first, last),
+		CanonicalCommit: true,
+	}
+	return NewFullCommit(commit, vals)
+}