Merge pull request #3185 from tendermint/release/v0.29.0

Release/v0.29.0

CHANGELOG.md

@@ -1,5 +1,77 @@
 # Changelog
 
+## v0.29.0
+
+*January 21, 2019*
+
+Special thanks to external contributors on this release:
+@bradyjoestar, @kunaldhariwal, @gauthamzz, @hrharder
+
+This release is primarily about making some breaking changes to
+the Block protocol version before Cosmos launch, and to fixing more issues
+in the proposer selection algorithm discovered on Cosmos testnets.
+
+The Block protocol changes include using a standard Merkle tree format (RFC 6962),
+fixing some inconsistencies between field orders in Vote and Proposal structs,
+and constraining the hash of the ConsensusParams to include only a few fields.
+
+The proposer selection algorithm saw significant progress,
+including a [formal proof by @cwgoes for the base-case in Idris](https://github.com/cwgoes/tm-proposer-idris)
+and a [much more detailed specification (still in progress) by
+@ancazamfir](https://github.com/tendermint/tendermint/pull/3140).
+
+Fixes to the proposer selection algorithm include normalizing the proposer
+priorities to mitigate the effects of large changes to the validator set.
+That said, we just discovered [another bug](https://github.com/tendermint/tendermint/issues/3181),
+which will be fixed in the next breaking release.
+
+While we are trying to stabilize the Block protocol to preserve compatibility
+with old chains, there may be some final changes yet to come before Cosmos
+launch as we continue to audit and test the software.
+
+Friendly reminder, we have a [bug bounty
+program](https://hackerone.com/tendermint).
+
+### BREAKING CHANGES:
+
+* CLI/RPC/Config
+
+* Apps
+  - [state] [\#3049](https://github.com/tendermint/tendermint/issues/3049) Total voting power of the validator set is upper bounded by
+    `MaxInt64 / 8`. Apps must ensure they do not return changes to the validator
+    set that cause this maximum to be exceeded.
+
+* Go API
+  - [node] [\#3082](https://github.com/tendermint/tendermint/issues/3082) MetricsProvider now requires you to pass a chain ID
+  - [types] [\#2713](https://github.com/tendermint/tendermint/issues/2713) Rename `TxProof.LeafHash` to `TxProof.Leaf`
+  - [crypto/merkle] [\#2713](https://github.com/tendermint/tendermint/issues/2713) `SimpleProof.Verify` takes a `leaf` instead of a
+    `leafHash` and performs the hashing itself
+
+* Blockchain Protocol
+  * [crypto/merkle] [\#2713](https://github.com/tendermint/tendermint/issues/2713) Merkle trees now match the RFC 6962 specification
+  * [types] [\#3078](https://github.com/tendermint/tendermint/issues/3078) Re-order Timestamp and BlockID in CanonicalVote so it's
+    consistent with CanonicalProposal (BlockID comes
+    first)
+  * [types] [\#3165](https://github.com/tendermint/tendermint/issues/3165) Hash of ConsensusParams only includes BlockSize.MaxBytes and
+    BlockSize.MaxGas
+
+* P2P Protocol
+  - [consensus] [\#3049](https://github.com/tendermint/tendermint/issues/3049) Normalize priorities to not exceed `2*TotalVotingPower` to mitigate unfair proposer selection
+    heavily preferring earlier joined validators in the case of an early bonded large validator unbonding
+
+### FEATURES:
+
+### IMPROVEMENTS:
+- [rpc] [\#3065](https://github.com/tendermint/tendermint/issues/3065) Return maxPerPage (100), not defaultPerPage (30) if `per_page` is greater than the max 100.
+- [instrumentation] [\#3082](https://github.com/tendermint/tendermint/issues/3082) Add `chain_id` label for all metrics
+
+### BUG FIXES:
+- [crypto] [\#3164](https://github.com/tendermint/tendermint/issues/3164) Update `btcd` fork for rare signRFC6979 bug
+- [lite] [\#3171](https://github.com/tendermint/tendermint/issues/3171) Fix verifying large validator set changes
+- [log] [\#3125](https://github.com/tendermint/tendermint/issues/3125) Fix year format
+- [mempool] [\#3168](https://github.com/tendermint/tendermint/issues/3168) Limit tx size to fit in the max reactor msg size
+- [scripts] [\#3147](https://github.com/tendermint/tendermint/issues/3147) Fix json2wal for large block parts (@bradyjoestar)
+
 ## v0.28.1
 
 *January 18th, 2019*

CHANGELOG_PENDING.md

@@ -1,4 +1,4 @@
-## v0.29.0
+## v0.30.0
 
 *TBD*
 

Gopkg.lock

@@ -361,11 +361,12 @@
   revision = "6b91fda63f2e36186f1c9d0e48578defb69c5d43"
 
 [[projects]]
-  digest = "1:605b6546f3f43745695298ec2d342d3e952b6d91cdf9f349bea9315f677d759f"
+  digest = "1:83f5e189eea2baad419a6a410984514266ff690075759c87e9ede596809bd0b8"
   name = "github.com/tendermint/btcd"
   packages = ["btcec"]
   pruneopts = "UT"
-  revision = "e5840949ff4fff0c56f9b6a541e22b63581ea9df"
+  revision = "80daadac05d1cd29571fccf27002d79667a88b58"
+  version = "v0.1.1"
 
 [[projects]]
   digest = "1:ad9c4c1a4e7875330b1f62906f2830f043a23edb5db997e3a5ac5d3e6eadf80a"

Gopkg.toml

@@ -75,6 +75,10 @@
   name = "github.com/prometheus/client_golang"
   version = "^0.9.1"
 
+[[constraint]]
+  name = "github.com/tendermint/btcd"
+  version = "v0.1.1"
+
 ###################################
 ## Some repos dont have releases.
 ## Pin to revision
@@ -92,9 +96,6 @@
   name = "github.com/btcsuite/btcutil"
   revision = "d4cc87b860166d00d6b5b9e0d3b3d71d6088d4d4"
 
-[[constraint]]
-  name = "github.com/tendermint/btcd"
-  revision = "e5840949ff4fff0c56f9b6a541e22b63581ea9df"
 
 [[constraint]]
   name = "github.com/rcrowley/go-metrics"

Makefile

@@ -292,9 +292,7 @@ build-linux:
 	GOOS=linux GOARCH=amd64 $(MAKE) build
 
 build-docker-localnode:
-	cd networks/local
-	make
-	cd -
+	@cd networks/local && make
 
 # Run a 4-node testnet locally
 localnet-start: localnet-stop

UPGRADING.md

@@ -3,6 +3,28 @@
 This guide provides steps to be followed when you upgrade your applications to
 a newer version of Tendermint Core.
 
+## v0.29.0
+
+This release contains some breaking changes to the block and p2p protocols,
+and will not be compatible with any previous versions of the software, primarily
+due to changes in how various data structures are hashed.
+
+Any implementations of Tendermint blockchain verification, including lite clients,
+will need to be updated. For specific details:
+- [Merkle tree](./docs/spec/blockchain/encoding.md#merkle-trees)
+- [ConsensusParams](./docs/spec/blockchain/state.md#consensusparams)
+
+There was also a small change to field ordering in the vote struct. Any
+implementations of an out-of-process validator (like a Key-Management Server)
+will need to be updated. For specific details:
+- [Vote](https://github.com/tendermint/tendermint/blob/develop/docs/spec/consensus/signing.md#votes)
+
+Finally, the proposer selection algorithm continues to evolve. See the
+[work-in-progress
+specification](https://github.com/tendermint/tendermint/pull/3140).
+
+For everything else, please see the [CHANGELOG](./CHANGELOG.md#v0.29.0).
+
 ## v0.28.0
 
 This release breaks the format for the `priv_validator.json` file

blockchain/store_test.go

@@ -311,7 +311,7 @@ func TestLoadBlockPart(t *testing.T) {
 	gotPart, _, panicErr := doFn(loadPart)
 	require.Nil(t, panicErr, "an existent and proper block should not panic")
 	require.Nil(t, res, "a properly saved block should return a proper block")
-	require.Equal(t, gotPart.(*types.Part).Hash(), part1.Hash(),
+	require.Equal(t, gotPart.(*types.Part), part1,
 		"expecting successful retrieval of previously saved block")
 }
 

consensus/metrics.go

@@ -8,7 +8,11 @@ import (
 	stdprometheus "github.com/prometheus/client_golang/prometheus"
 )
 
-const MetricsSubsystem = "consensus"
+const (
+	// MetricsSubsystem is a subsystem shared by all metrics exposed by this
+	// package.
+	MetricsSubsystem = "consensus"
+)
 
 // Metrics contains metrics exposed by this package.
 type Metrics struct {
@@ -50,101 +54,107 @@ type Metrics struct {
 }
 
 // PrometheusMetrics returns Metrics build using Prometheus client library.
-func PrometheusMetrics(namespace string) *Metrics {
+// Optionally, labels can be provided along with their values ("foo",
+// "fooValue").
+func PrometheusMetrics(namespace string, labelsAndValues ...string) *Metrics {
+	labels := []string{}
+	for i := 0; i < len(labelsAndValues); i += 2 {
+		labels = append(labels, labelsAndValues[i])
+	}
 	return &Metrics{
 		Height: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "height",
 			Help:      "Height of the chain.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		Rounds: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "rounds",
 			Help:      "Number of rounds.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 
 		Validators: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "validators",
 			Help:      "Number of validators.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		ValidatorsPower: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "validators_power",
 			Help:      "Total power of all validators.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		MissingValidators: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "missing_validators",
 			Help:      "Number of validators who did not sign.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		MissingValidatorsPower: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "missing_validators_power",
 			Help:      "Total power of the missing validators.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		ByzantineValidators: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "byzantine_validators",
 			Help:      "Number of validators who tried to double sign.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		ByzantineValidatorsPower: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "byzantine_validators_power",
 			Help:      "Total power of the byzantine validators.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 
 		BlockIntervalSeconds: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "block_interval_seconds",
 			Help:      "Time between this and the last block.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 
 		NumTxs: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "num_txs",
 			Help:      "Number of transactions.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		BlockSizeBytes: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "block_size_bytes",
 			Help:      "Size of the block.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		TotalTxs: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "total_txs",
 			Help:      "Total number of transactions.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		CommittedHeight: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "latest_block_height",
 			Help:      "The latest block height.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		FastSyncing: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "fast_syncing",
 			Help:      "Whether or not a node is fast syncing. 1 if yes, 0 if no.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		BlockParts: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "block_parts",
 			Help:      "Number of blockparts transmitted by peer.",
-		}, []string{"peer_id"}),
+		}, append(labels, "peer_id")).With(labelsAndValues...),
 	}
 }
 

crypto/merkle/hash.go

@@ -0,0 +1,21 @@
+package merkle
+
+import (
+	"github.com/tendermint/tendermint/crypto/tmhash"
+)
+
+// TODO: make these have a large predefined capacity
+var (
+	leafPrefix  = []byte{0}
+	innerPrefix = []byte{1}
+)
+
+// returns tmhash(0x00 || leaf)
+func leafHash(leaf []byte) []byte {
+	return tmhash.Sum(append(leafPrefix, leaf...))
+}
+
+// returns tmhash(0x01 || left || right)
+func innerHash(left []byte, right []byte) []byte {
+	return tmhash.Sum(append(innerPrefix, append(left, right...)...))
+}

crypto/merkle/proof_simple_value.go

@@ -71,11 +71,11 @@ func (op SimpleValueOp) Run(args [][]byte) ([][]byte, error) {
 	hasher.Write(value) // does not error
 	vhash := hasher.Sum(nil)
 
+	bz := new(bytes.Buffer)
 	// Wrap <op.Key, vhash> to hash the KVPair.
-	hasher = tmhash.New()
-	encodeByteSlice(hasher, []byte(op.key)) // does not error
-	encodeByteSlice(hasher, []byte(vhash))  // does not error
-	kvhash := hasher.Sum(nil)
+	encodeByteSlice(bz, []byte(op.key)) // does not error
+	encodeByteSlice(bz, []byte(vhash))  // does not error
+	kvhash := leafHash(bz.Bytes())
 
 	if !bytes.Equal(kvhash, op.Proof.LeafHash) {
 		return nil, cmn.NewError("leaf hash mismatch: want %X got %X", op.Proof.LeafHash, kvhash)

crypto/merkle/rfc6962_test.go

@@ -0,0 +1,97 @@
+package merkle
+
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// These tests were taken from https://github.com/google/trillian/blob/master/merkle/rfc6962/rfc6962_test.go,
+// and consequently fall under the above license.
+import (
+	"bytes"
+	"encoding/hex"
+	"testing"
+
+	"github.com/tendermint/tendermint/crypto/tmhash"
+)
+
+func TestRFC6962Hasher(t *testing.T) {
+	_, leafHashTrail := trailsFromByteSlices([][]byte{[]byte("L123456")})
+	leafHash := leafHashTrail.Hash
+	_, leafHashTrail = trailsFromByteSlices([][]byte{[]byte{}})
+	emptyLeafHash := leafHashTrail.Hash
+	for _, tc := range []struct {
+		desc string
+		got  []byte
+		want string
+	}{
+		// Since creating a merkle tree of no leaves is unsupported here, we skip
+		// the corresponding trillian test vector.
+
+		// Check that the empty hash is not the same as the hash of an empty leaf.
+		// echo -n 00 | xxd -r -p | sha256sum
+		{
+			desc: "RFC6962 Empty Leaf",
+			want: "6e340b9cffb37a989ca544e6bb780a2c78901d3fb33738768511a30617afa01d"[:tmhash.Size*2],
+			got:  emptyLeafHash,
+		},
+		// echo -n 004C313233343536 | xxd -r -p | sha256sum
+		{
+			desc: "RFC6962 Leaf",
+			want: "395aa064aa4c29f7010acfe3f25db9485bbd4b91897b6ad7ad547639252b4d56"[:tmhash.Size*2],
+			got:  leafHash,
+		},
+		// echo -n 014E3132334E343536 | xxd -r -p | sha256sum
+		{
+			desc: "RFC6962 Node",
+			want: "aa217fe888e47007fa15edab33c2b492a722cb106c64667fc2b044444de66bbb"[:tmhash.Size*2],
+			got:  innerHash([]byte("N123"), []byte("N456")),
+		},
+	} {
+		t.Run(tc.desc, func(t *testing.T) {
+			wantBytes, err := hex.DecodeString(tc.want)
+			if err != nil {
+				t.Fatalf("hex.DecodeString(%x): %v", tc.want, err)
+			}
+			if got, want := tc.got, wantBytes; !bytes.Equal(got, want) {
+				t.Errorf("got %x, want %x", got, want)
+			}
+		})
+	}
+}
+
+func TestRFC6962HasherCollisions(t *testing.T) {
+	// Check that different leaves have different hashes.
+	leaf1, leaf2 := []byte("Hello"), []byte("World")
+	_, leafHashTrail := trailsFromByteSlices([][]byte{leaf1})
+	hash1 := leafHashTrail.Hash
+	_, leafHashTrail = trailsFromByteSlices([][]byte{leaf2})
+	hash2 := leafHashTrail.Hash
+	if bytes.Equal(hash1, hash2) {
+		t.Errorf("Leaf hashes should differ, but both are %x", hash1)
+	}
+	// Compute an intermediate subtree hash.
+	_, subHash1Trail := trailsFromByteSlices([][]byte{hash1, hash2})
+	subHash1 := subHash1Trail.Hash
+	// Check that this is not the same as a leaf hash of their concatenation.
+	preimage := append(hash1, hash2...)
+	_, forgedHashTrail := trailsFromByteSlices([][]byte{preimage})
+	forgedHash := forgedHashTrail.Hash
+	if bytes.Equal(subHash1, forgedHash) {
+		t.Errorf("Hasher is not second-preimage resistant")
+	}
+	// Swap the order of nodes and check that the hash is different.
+	_, subHash2Trail := trailsFromByteSlices([][]byte{hash2, hash1})
+	subHash2 := subHash2Trail.Hash
+	if bytes.Equal(subHash1, subHash2) {
+		t.Errorf("Subtree hash does not depend on the order of leaves")
+	}
+}

crypto/merkle/simple_map_test.go

@@ -13,14 +13,14 @@ func TestSimpleMap(t *testing.T) {
 		values []string // each string gets converted to []byte in test
 		want   string
 	}{
-		{[]string{"key1"}, []string{"value1"}, "321d150de16dceb51c72981b432b115045383259b1a550adf8dc80f927508967"},
-		{[]string{"key1"}, []string{"value2"}, "2a9e4baf321eac99f6eecc3406603c14bc5e85bb7b80483cbfc75b3382d24a2f"},
+		{[]string{"key1"}, []string{"value1"}, "a44d3cc7daba1a4600b00a2434b30f8b970652169810d6dfa9fb1793a2189324"},
+		{[]string{"key1"}, []string{"value2"}, "0638e99b3445caec9d95c05e1a3fc1487b4ddec6a952ff337080360b0dcc078c"},
 		// swap order with 2 keys
-		{[]string{"key1", "key2"}, []string{"value1", "value2"}, "c4d8913ab543ba26aa970646d4c99a150fd641298e3367cf68ca45fb45a49881"},
-		{[]string{"key2", "key1"}, []string{"value2", "value1"}, "c4d8913ab543ba26aa970646d4c99a150fd641298e3367cf68ca45fb45a49881"},
+		{[]string{"key1", "key2"}, []string{"value1", "value2"}, "8fd19b19e7bb3f2b3ee0574027d8a5a4cec370464ea2db2fbfa5c7d35bb0cff3"},
+		{[]string{"key2", "key1"}, []string{"value2", "value1"}, "8fd19b19e7bb3f2b3ee0574027d8a5a4cec370464ea2db2fbfa5c7d35bb0cff3"},
 		// swap order with 3 keys
-		{[]string{"key1", "key2", "key3"}, []string{"value1", "value2", "value3"}, "b23cef00eda5af4548a213a43793f2752d8d9013b3f2b64bc0523a4791196268"},
-		{[]string{"key1", "key3", "key2"}, []string{"value1", "value3", "value2"}, "b23cef00eda5af4548a213a43793f2752d8d9013b3f2b64bc0523a4791196268"},
+		{[]string{"key1", "key2", "key3"}, []string{"value1", "value2", "value3"}, "1dd674ec6782a0d586a903c9c63326a41cbe56b3bba33ed6ff5b527af6efb3dc"},
+		{[]string{"key1", "key3", "key2"}, []string{"value1", "value3", "value2"}, "1dd674ec6782a0d586a903c9c63326a41cbe56b3bba33ed6ff5b527af6efb3dc"},
 	}
 	for i, tc := range tests {
 		db := newSimpleMap()

crypto/merkle/simple_proof.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 
-	"github.com/tendermint/tendermint/crypto/tmhash"
 	cmn "github.com/tendermint/tendermint/libs/common"
 )
 
@@ -67,7 +66,8 @@ func SimpleProofsFromMap(m map[string][]byte) (rootHash []byte, proofs map[strin
 
 // Verify that the SimpleProof proves the root hash.
 // Check sp.Index/sp.Total manually if needed
-func (sp *SimpleProof) Verify(rootHash []byte, leafHash []byte) error {
+func (sp *SimpleProof) Verify(rootHash []byte, leaf []byte) error {
+	leafHash := leafHash(leaf)
 	if sp.Total < 0 {
 		return errors.New("Proof total must be positive")
 	}
@@ -128,19 +128,19 @@ func computeHashFromAunts(index int, total int, leafHash []byte, innerHashes [][
 		if len(innerHashes) == 0 {
 			return nil
 		}
-		numLeft := (total + 1) / 2
+		numLeft := getSplitPoint(total)
 		if index < numLeft {
 			leftHash := computeHashFromAunts(index, numLeft, leafHash, innerHashes[:len(innerHashes)-1])
 			if leftHash == nil {
 				return nil
 			}
-			return simpleHashFromTwoHashes(leftHash, innerHashes[len(innerHashes)-1])
+			return innerHash(leftHash, innerHashes[len(innerHashes)-1])
 		}
 		rightHash := computeHashFromAunts(index-numLeft, total-numLeft, leafHash, innerHashes[:len(innerHashes)-1])
 		if rightHash == nil {
 			return nil
 		}
-		return simpleHashFromTwoHashes(innerHashes[len(innerHashes)-1], rightHash)
+		return innerHash(innerHashes[len(innerHashes)-1], rightHash)
 	}
 }
 
@@ -182,12 +182,13 @@ func trailsFromByteSlices(items [][]byte) (trails []*SimpleProofNode, root *Simp
 	case 0:
 		return nil, nil
 	case 1:
-		trail := &SimpleProofNode{tmhash.Sum(items[0]), nil, nil, nil}
+		trail := &SimpleProofNode{leafHash(items[0]), nil, nil, nil}
 		return []*SimpleProofNode{trail}, trail
 	default:
-		lefts, leftRoot := trailsFromByteSlices(items[:(len(items)+1)/2])
-		rights, rightRoot := trailsFromByteSlices(items[(len(items)+1)/2:])
-		rootHash := simpleHashFromTwoHashes(leftRoot.Hash, rightRoot.Hash)
+		k := getSplitPoint(len(items))
+		lefts, leftRoot := trailsFromByteSlices(items[:k])
+		rights, rightRoot := trailsFromByteSlices(items[k:])
+		rootHash := innerHash(leftRoot.Hash, rightRoot.Hash)
 		root := &SimpleProofNode{rootHash, nil, nil, nil}
 		leftRoot.Parent = root
 		leftRoot.Right = rightRoot

crypto/merkle/simple_tree.go

@@ -1,23 +1,9 @@
 package merkle
 
 import (
-	"github.com/tendermint/tendermint/crypto/tmhash"
+	"math/bits"
 )
 
-// simpleHashFromTwoHashes is the basic operation of the Merkle tree: Hash(left | right).
-func simpleHashFromTwoHashes(left, right []byte) []byte {
-	var hasher = tmhash.New()
-	err := encodeByteSlice(hasher, left)
-	if err != nil {
-		panic(err)
-	}
-	err = encodeByteSlice(hasher, right)
-	if err != nil {
-		panic(err)
-	}
-	return hasher.Sum(nil)
-}
-
 // SimpleHashFromByteSlices computes a Merkle tree where the leaves are the byte slice,
 // in the provided order.
 func SimpleHashFromByteSlices(items [][]byte) []byte {
@@ -25,11 +11,12 @@ func SimpleHashFromByteSlices(items [][]byte) []byte {
 	case 0:
 		return nil
 	case 1:
-		return tmhash.Sum(items[0])
+		return leafHash(items[0])
 	default:
-		left := SimpleHashFromByteSlices(items[:(len(items)+1)/2])
-		right := SimpleHashFromByteSlices(items[(len(items)+1)/2:])
-		return simpleHashFromTwoHashes(left, right)
+		k := getSplitPoint(len(items))
+		left := SimpleHashFromByteSlices(items[:k])
+		right := SimpleHashFromByteSlices(items[k:])
+		return innerHash(left, right)
 	}
 }
 
@@ -44,3 +31,17 @@ func SimpleHashFromMap(m map[string][]byte) []byte {
 	}
 	return sm.Hash()
 }
+
+// getSplitPoint returns the largest power of 2 less than length
+func getSplitPoint(length int) int {
+	if length < 1 {
+		panic("Trying to split a tree with size < 1")
+	}
+	uLength := uint(length)
+	bitlen := bits.Len(uLength)
+	k := 1 << uint(bitlen-1)
+	if k == length {
+		k >>= 1
+	}
+	return k
+}

crypto/merkle/simple_tree_test.go

@@ -34,7 +34,6 @@ func TestSimpleProof(t *testing.T) {
 
 	// For each item, check the trail.
 	for i, item := range items {
-		itemHash := tmhash.Sum(item)
 		proof := proofs[i]
 
 		// Check total/index
@@ -43,30 +42,53 @@ func TestSimpleProof(t *testing.T) {
 		require.Equal(t, proof.Total, total, "Unmatched totals: %d vs %d", proof.Total, total)
 
 		// Verify success
-		err := proof.Verify(rootHash, itemHash)
-		require.NoError(t, err, "Verificatior failed: %v.", err)
+		err := proof.Verify(rootHash, item)
+		require.NoError(t, err, "Verification failed: %v.", err)
 
 		// Trail too long should make it fail
 		origAunts := proof.Aunts
 		proof.Aunts = append(proof.Aunts, cmn.RandBytes(32))
-		err = proof.Verify(rootHash, itemHash)
+		err = proof.Verify(rootHash, item)
 		require.Error(t, err, "Expected verification to fail for wrong trail length")
 
 		proof.Aunts = origAunts
 
 		// Trail too short should make it fail
 		proof.Aunts = proof.Aunts[0 : len(proof.Aunts)-1]
-		err = proof.Verify(rootHash, itemHash)
+		err = proof.Verify(rootHash, item)
 		require.Error(t, err, "Expected verification to fail for wrong trail length")
 
 		proof.Aunts = origAunts
 
 		// Mutating the itemHash should make it fail.
-		err = proof.Verify(rootHash, MutateByteSlice(itemHash))
+		err = proof.Verify(rootHash, MutateByteSlice(item))
 		require.Error(t, err, "Expected verification to fail for mutated leaf hash")
 
 		// Mutating the rootHash should make it fail.
-		err = proof.Verify(MutateByteSlice(rootHash), itemHash)
+		err = proof.Verify(MutateByteSlice(rootHash), item)
 		require.Error(t, err, "Expected verification to fail for mutated root hash")
 	}
 }
+
+func Test_getSplitPoint(t *testing.T) {
+	tests := []struct {
+		length int
+		want   int
+	}{
+		{1, 0},
+		{2, 1},
+		{3, 2},
+		{4, 2},
+		{5, 4},
+		{10, 8},
+		{20, 16},
+		{100, 64},
+		{255, 128},
+		{256, 128},
+		{257, 256},
+	}
+	for _, tt := range tests {
+		got := getSplitPoint(tt.length)
+		require.Equal(t, tt.want, got, "getSplitPoint(%d) = %v, want %v", tt.length, got, tt.want)
+	}
+}

docs/app-dev/app-architecture.md

@@ -45,6 +45,6 @@ Tendermint.
 See the following for more extensive documentation:
 
 - [Interchain Standard for the Light-Client REST API](https://github.com/cosmos/cosmos-sdk/pull/1028)
-- [Tendermint RPC Docs](https://tendermint.github.io/slate/)
+- [Tendermint RPC Docs](https://tendermint.com/rpc/)
 - [Tendermint in Production](../tendermint-core/running-in-production.md)
 - [ABCI spec](./abci-spec.md)

docs/app-dev/ecosystem.json

@@ -63,6 +63,13 @@
       "author": "Zach Balder",
       "description": "Public service reporting and tracking"
     },
+    {
+      "name": "ParadigmCore",
+      "url": "https://github.com/ParadigmFoundation/ParadigmCore",
+      "language": "TypeScript",
+      "author": "Paradigm Labs",
+      "description": "Reference implementation of the Paradigm Protocol, and OrderStream network client."
+    },
     {
       "name": "Passchain",
       "url": "https://github.com/trusch/passchain",

docs/app-dev/indexing-transactions.md

@@ -78,7 +78,7 @@ endpoint:
 curl "localhost:26657/tx_search?query=\"account.name='igor'\"&prove=true"
 ```
 
-Check out [API docs](https://tendermint.github.io/slate/?shell#txsearch)
+Check out [API docs](https://tendermint.com/rpc/#txsearch)
 for more information on query syntax and other options.
 
 ## Subscribing to transactions
@@ -97,5 +97,5 @@ by providing a query to `/subscribe` RPC endpoint.
 }
 ```
 
-Check out [API docs](https://tendermint.github.io/slate/#subscribe) for
+Check out [API docs](https://tendermint.com/rpc/#subscribe) for
 more information on query syntax and other options.

docs/architecture/adr-020-block-size.md

@@ -7,6 +7,7 @@
 28-08-2018: Third version after Ethan's comments
 30-08-2018: AminoOverheadForBlock => MaxAminoOverheadForBlock
 31-08-2018: Bounding evidence and chain ID
+13-01-2019: Add section on MaxBytes vs MaxDataBytes
 
 ## Context
 
@@ -20,6 +21,32 @@ We should just remove MaxTxs all together and stick with MaxBytes, and have a
 But we can't just reap BlockSize.MaxBytes, since MaxBytes is for the entire block,
 not for the txs inside the block. There's extra amino overhead + the actual
 headers on top of the actual transactions + evidence + last commit.
+We could also consider using a MaxDataBytes instead of or in addition to MaxBytes.
+
+## MaxBytes vs MaxDataBytes
+
+The [PR #3045](https://github.com/tendermint/tendermint/pull/3045) suggested
+additional clarity/justification was necessary here, wither respect to the use
+of MaxDataBytes in addition to, or instead of, MaxBytes.
+
+MaxBytes provides a clear limit on the total size of a block that requires no
+additional calculation if you want to use it to bound resource usage, and there
+has been considerable discussions about optimizing tendermint around 1MB blocks.
+Regardless, we need some maximum on the size of a block so we can avoid
+unmarshalling blocks that are too big during the consensus, and it seems more
+straightforward to provide a single fixed number for this rather than a
+computation of "MaxDataBytes + everything else you need to make room for
+(signatures, evidence, header)". MaxBytes provides a simple bound so we can
+always say "blocks are less than X MB".
+
+Having both MaxBytes and MaxDataBytes feels like unnecessary complexity. It's
+not particularly surprising for MaxBytes to imply the maximum size of the
+entire block (not just txs), one just has to know that a block includes header,
+txs, evidence, votes. For more fine grained control over the txs included in the
+block, there is the MaxGas. In practice, the MaxGas may be expected to do most of
+the tx throttling, and the MaxBytes to just serve as an upper bound on the total
+size. Applications can use MaxGas as a MaxDataBytes by just taking the gas for
+every tx to be its size in bytes.
 
 ## Proposed solution
 
@@ -61,7 +88,7 @@ MaxXXX stayed the same.
 
 ## Status
 
-Proposed.
+Accepted.
 
 ## Consequences
 

docs/networks/docker-compose.md

@@ -4,7 +4,7 @@ With Docker Compose, you can spin up local testnets with a single command.
 
 ## Requirements
 
-1. [Install tendermint](/docs/install.md)
+1. [Install tendermint](/docs/introduction/install.md)
 2. [Install docker](https://docs.docker.com/engine/installation/)
 3. [Install docker-compose](https://docs.docker.com/compose/install/)
 

docs/spec/abci/apps.md

@@ -166,6 +166,11 @@ the tags will be hashed into the next block header.
 The application may set the validator set during InitChain, and update it during
 EndBlock.
 
+Note that the maximum total power of the validator set is bounded by
+`MaxTotalVotingPower = MaxInt64 / 8`. Applications are responsible for ensuring
+they do not make changes to the validator set that cause it to exceed this
+limit.
+
 ### InitChain
 
 ResponseInitChain can return a list of validators.
@@ -206,6 +211,7 @@ following rules:
   - if the validator does not already exist, it will be added to the validator
     set with the given power
   - if the validator does already exist, its power will be adjusted to the given power
+- the total power of the new validator set must not exceed MaxTotalVotingPower
 
 Note the updates returned in block `H` will only take effect at block `H+2`.
 

docs/spec/blockchain/blockchain.md

@@ -51,7 +51,7 @@ type Header struct {
 
 	// hashes of block data
 	LastCommitHash []byte // commit from validators from the last block
-	DataHash       []byte // Merkle root of transactions
+	DataHash       []byte // MerkleRoot of transaction hashes
 
 	// hashes from the app output from the prev block
 	ValidatorsHash     []byte // validators for the current block
@@ -83,25 +83,27 @@ type Version struct {
 ## BlockID
 
 The `BlockID` contains two distinct Merkle roots of the block.
-The first, used as the block's main hash, is the Merkle root
-of all the fields in the header. The second, used for secure gossipping of
-the block during consensus, is the Merkle root of the complete serialized block
-cut into parts. The `BlockID` includes these two hashes, as well as the number of
-parts.
+The first, used as the block's main hash, is the MerkleRoot
+of all the fields in the header (ie. `MerkleRoot(header)`.
+The second, used for secure gossipping of the block during consensus,
+is the MerkleRoot of the complete serialized block
+cut into parts (ie. `MerkleRoot(MakeParts(block))`).
+The `BlockID` includes these two hashes, as well as the number of
+parts (ie. `len(MakeParts(block))`)
 
 ```go
 type BlockID struct {
     Hash []byte
-    Parts PartsHeader
+    PartsHeader PartSetHeader
 }
 
-type PartsHeader struct {
-    Hash []byte
+type PartSetHeader struct {
     Total int32
+    Hash []byte
 }
 ```
 
-TODO: link to details of merkle sums.
+See [MerkleRoot](/docs/spec/blockchain/encoding.md#MerkleRoot) for details.
 
 ## Time
 
@@ -109,10 +111,6 @@ Tendermint uses the
 [Google.Protobuf.WellKnownTypes.Timestamp](https://developers.google.com/protocol-buffers/docs/reference/csharp/class/google/protobuf/well-known-types/timestamp)
 format, which uses two integers, one for Seconds and for Nanoseconds.
 
-NOTE: there is currently a small divergence between Tendermint and the
-Google.Protobuf.WellKnownTypes.Timestamp that should be resolved. See [this
-issue](https://github.com/tendermint/go-amino/issues/223) for details.
-
 ## Data
 
 Data is just a wrapper for a list of transactions, where transactions are
@@ -146,12 +144,12 @@ The vote includes information about the validator signing it.
 
 ```go
 type Vote struct {
-	Type             SignedMsgType  // byte
+	Type             byte
 	Height           int64
 	Round            int
-	Timestamp        time.Time
 	BlockID          BlockID
-	ValidatorAddress Address
+	Timestamp        Time
+	ValidatorAddress []byte
 	ValidatorIndex   int
 	Signature        []byte
 }
@@ -164,8 +162,8 @@ a _precommit_ has `vote.Type == 2`.
 ## Signature
 
 Signatures in Tendermint are raw bytes representing the underlying signature.
-The only signature scheme currently supported for Tendermint validators is
-ED25519. The signature is the raw 64-byte ED25519 signature.
+
+See the [signature spec](/docs/spec/blockchain/encoding.md#key-types) for more.
 
 ## EvidenceData
 
@@ -192,6 +190,8 @@ type DuplicateVoteEvidence struct {
 }
 ```
 
+See the [pubkey spec](/docs/spec/blockchain/encoding.md#key-types) for more.
+
 ## Validation
 
 Here we describe the validation rules for every element in a block.
@@ -209,7 +209,7 @@ the current version of the `state` corresponds to the state
 after executing transactions from the `prevBlock`.
 Elements of an object are accessed as expected,
 ie. `block.Header`.
-See [here](https://github.com/tendermint/tendermint/blob/master/docs/spec/blockchain/state.md) for the definition of `state`.
+See the [definition of `State`](/docs/spec/blockchain/state.md).
 
 ### Header
 
@@ -288,28 +288,25 @@ The first block has `block.Header.TotalTxs = block.Header.NumberTxs`.
 LastBlockID is the previous block's BlockID:
 
 ```go
-prevBlockParts := MakeParts(prevBlock, state.LastConsensusParams.BlockGossip.BlockPartSize)
+prevBlockParts := MakeParts(prevBlock)
 block.Header.LastBlockID == BlockID {
-    Hash: SimpleMerkleRoot(prevBlock.Header),
+    Hash: MerkleRoot(prevBlock.Header),
     PartsHeader{
-        Hash: SimpleMerkleRoot(prevBlockParts),
+        Hash: MerkleRoot(prevBlockParts),
         Total: len(prevBlockParts),
     },
 }
 ```
 
-Note: it depends on the ConsensusParams,
-which are held in the `state` and may be updated by the application.
-
 The first block has `block.Header.LastBlockID == BlockID{}`.
 
 ### LastCommitHash
 
 ```go
-block.Header.LastCommitHash == SimpleMerkleRoot(block.LastCommit)
+block.Header.LastCommitHash == MerkleRoot(block.LastCommit.Precommits)
 ```
 
-Simple Merkle root of the votes included in the block.
+MerkleRoot of the votes included in the block.
 These are the votes that committed the previous block.
 
 The first block has `block.Header.LastCommitHash == []byte{}`
@@ -317,37 +314,42 @@ The first block has `block.Header.LastCommitHash == []byte{}`
 ### DataHash
 
 ```go
-block.Header.DataHash == SimpleMerkleRoot(block.Txs.Txs)
+block.Header.DataHash == MerkleRoot(Hashes(block.Txs.Txs))
 ```
 
-Simple Merkle root of the transactions included in the block.
+MerkleRoot of the hashes of transactions included in the block.
+
+Note the transactions are hashed before being included in the Merkle tree,
+so the leaves of the Merkle tree are the hashes, not the transactions
+themselves. This is because transaction hashes are regularly used as identifiers for
+transactions.
 
 ### ValidatorsHash
 
 ```go
-block.ValidatorsHash == SimpleMerkleRoot(state.Validators)
+block.ValidatorsHash == MerkleRoot(state.Validators)
 ```
 
-Simple Merkle root of the current validator set that is committing the block.
+MerkleRoot of the current validator set that is committing the block.
 This can be used to validate the `LastCommit` included in the next block.
 
 ### NextValidatorsHash
 
 ```go
-block.NextValidatorsHash == SimpleMerkleRoot(state.NextValidators)
+block.NextValidatorsHash == MerkleRoot(state.NextValidators)
 ```
 
-Simple Merkle root of the next validator set that will be the validator set that commits the next block.
+MerkleRoot of the next validator set that will be the validator set that commits the next block.
 This is included so that the current validator set gets a chance to sign the
 next validator sets Merkle root.
 
-### ConsensusParamsHash
+### ConsensusHash
 
 ```go
-block.ConsensusParamsHash == TMHASH(amino(state.ConsensusParams))
+block.ConsensusHash == state.ConsensusParams.Hash()
 ```
 
-Hash of the amino-encoded consensus parameters.
+Hash of the amino-encoding of a subset of the consensus parameters.
 
 ### AppHash
 
@@ -362,20 +364,20 @@ The first block has `block.Header.AppHash == []byte{}`.
 ### LastResultsHash
 
 ```go
-block.ResultsHash == SimpleMerkleRoot(state.LastResults)
+block.ResultsHash == MerkleRoot(state.LastResults)
 ```
 
-Simple Merkle root of the results of the transactions in the previous block.
+MerkleRoot of the results of the transactions in the previous block.
 
 The first block has `block.Header.ResultsHash == []byte{}`.
 
 ## EvidenceHash
 
 ```go
-block.EvidenceHash == SimpleMerkleRoot(block.Evidence)
+block.EvidenceHash == MerkleRoot(block.Evidence)
 ```
 
-Simple Merkle root of the evidence of Byzantine behaviour included in this block.
+MerkleRoot of the evidence of Byzantine behaviour included in this block.
 
 ### ProposerAddress
 

docs/spec/blockchain/encoding.md

@@ -30,6 +30,12 @@ For example, the byte-array `[0xA, 0xB]` would be encoded as `0x020A0B`,
 while a byte-array containing 300 entires beginning with `[0xA, 0xB, ...]` would
 be encoded as `0xAC020A0B...` where `0xAC02` is the UVarint encoding of 300.
 
+## Hashing
+
+Tendermint uses `SHA256` as its hash function.
+Objects are always Amino encoded before being hashed.
+So `SHA256(obj)` is short for `SHA256(AminoEncode(obj))`.
+
 ## Public Key Cryptography
 
 Tendermint uses Amino to distinguish between different types of private keys,
@@ -68,23 +74,27 @@ For example, the 33-byte (or 0x21-byte in hex) Secp256k1 pubkey
    would be encoded as
    `EB5AE98721020BD40F225A57ED383B440CF073BC5539D0341F5767D2BF2D78406D00475A2EE9`
 
-### Addresses
+### Key Types
 
-Addresses for each public key types are computed as follows:
+Each type specifies it's own pubkey, address, and signature format.
 
 #### Ed25519
 
-First 20-bytes of the SHA256 hash of the raw 32-byte public key:
+TODO: pubkey
+
+The address is the first 20-bytes of the SHA256 hash of the raw 32-byte public key:
 
 ```
 address = SHA256(pubkey)[:20]
 ```
 
-NOTE: before v0.22.0, this was the RIPEMD160 of the Amino encoded public key.
+The signature is the raw 64-byte ED25519 signature.
 
 #### Secp256k1
 
-RIPEMD160 hash of the SHA256 hash of the OpenSSL compressed public key:
+TODO: pubkey
+
+The address is the RIPEMD160 hash of the SHA256 hash of the OpenSSL compressed public key:
 
 ```
 address = RIPEMD160(SHA256(pubkey))
@@ -92,12 +102,21 @@ address = RIPEMD160(SHA256(pubkey))
 
 This is the same as Bitcoin.
 
+The signature is the 64-byte concatenation of ECDSA `r` and `s` (ie. `r || s`),
+where `s` is lexicographically less than its inverse, to prevent malleability.
+This is like Ethereum, but without the extra byte for pubkey recovery, since
+Tendermint assumes the pubkey is always provided anyway.
+
+#### Multisig
+
+TODO
+
 ## Other Common Types
 
 ### BitArray
 
-The BitArray is used in block headers and some consensus messages to signal
-whether or not something was done by each validator. BitArray is represented
+The BitArray is used in some consensus messages to represent votes received from
+validators, or parts received in a block. It is represented
 with a struct containing the number of bits (`Bits`) and the bit-array itself
 encoded in base64 (`Elems`).
 
@@ -119,24 +138,27 @@ representing `1` and `0`. Ie. the BitArray `10110` would be JSON encoded as
 Part is used to break up blocks into pieces that can be gossiped in parallel
 and securely verified using a Merkle tree of the parts.
 
-Part contains the index of the part in the larger set (`Index`), the actual
-underlying data of the part (`Bytes`), and a simple Merkle proof that the part is contained in
-the larger set (`Proof`).
+Part contains the index of the part (`Index`), the actual
+underlying data of the part (`Bytes`), and a Merkle proof that the part is contained in
+the set (`Proof`).
 
 ```go
 type Part struct {
     Index int
-    Bytes byte[]
-    Proof byte[]
+    Bytes []byte
+    Proof SimpleProof
 }
 ```
 
+See details of SimpleProof, below.
+
 ### MakeParts
 
 Encode an object using Amino and slice it into parts.
+Tendermint uses a part size of 65536 bytes.
 
 ```go
-func MakeParts(obj interface{}, partSize int) []Part
+func MakeParts(block Block) []Part
 ```
 
 ## Merkle Trees
@@ -144,12 +166,17 @@ func MakeParts(obj interface{}, partSize int) []Part
 For an overview of Merkle trees, see
 [wikipedia](https://en.wikipedia.org/wiki/Merkle_tree)
 
-A Simple Tree is a simple compact binary tree for a static list of items. Simple Merkle trees are used in numerous places in Tendermint to compute a cryptographic digest of a data structure. In a Simple Tree, the transactions and validation signatures of a block are hashed using this simple merkle tree logic.
+We use the RFC 6962 specification of a merkle tree, with sha256 as the hash function.
+Merkle trees are used throughout Tendermint to compute a cryptographic digest of a data structure.
+The differences between RFC 6962 and the simplest form a merkle tree are that:
+
+1) leaf nodes and inner nodes have different hashes.
+   This is for "second pre-image resistance", to prevent the proof to an inner node being valid as the proof of a leaf.
+   The leaf nodes are `SHA256(0x00 || leaf_data)`, and inner nodes are `SHA256(0x01 || left_hash || right_hash)`.
 
-If the number of items is not a power of two, the tree will not be full
-and some leaf nodes will be at different levels. Simple Tree tries to
-keep both sides of the tree the same size, but the left side may be one
-greater, for example:
+2) When the number of items isn't a power of two, the left half of the tree is as big as it could be.
+   (The smallest power of two less than the number of items) This allows new leaves to be added with less
+   recomputation. For example:
 
 ```
    Simple Tree with 6 items           Simple Tree with 7 items
@@ -163,68 +190,79 @@ greater, for example:
      / \             / \                / \             / \
     /   \           /   \              /   \           /   \
    /     \         /     \            /     \         /     \
-  *       h2      *       h5         *       *       *       h6
- / \             / \                / \     / \     / \
-h0  h1          h3  h4             h0  h1  h2  h3  h4  h5
-```
-
-Tendermint always uses the `TMHASH` hash function, which is equivalent to
-SHA256:
-
-```
-func TMHASH(bz []byte) []byte {
-    return SHA256(bz)
-}
+  *       *       h4     h5          *       *       *       h6
+ / \     / \                        / \     / \     / \
+h0  h1  h2 h3                      h0  h1  h2  h3  h4  h5
 ```
 
-### Simple Merkle Root
+### MerkleRoot
 
-The function `SimpleMerkleRoot` is a simple recursive function defined as follows:
+The function `MerkleRoot` is a simple recursive function defined as follows:
 
 ```go
-func SimpleMerkleRoot(hashes [][]byte) []byte{
-    switch len(hashes) {
-    case 0:
-        return nil
-    case 1:
-        return hashes[0]
-    default:
-        left := SimpleMerkleRoot(hashes[:(len(hashes)+1)/2])
-        right := SimpleMerkleRoot(hashes[(len(hashes)+1)/2:])
-        return SimpleConcatHash(left, right)
-    }
+// SHA256(0x00 || leaf)
+func leafHash(leaf []byte) []byte {
+	return tmhash.Sum(append(0x00, leaf...))
 }
 
-func SimpleConcatHash(left, right []byte) []byte{
-    left = encodeByteSlice(left)
-    right = encodeByteSlice(right)
-    return TMHASH(append(left, right))
+// SHA256(0x01 || left || right)
+func innerHash(left []byte, right []byte) []byte {
+	return tmhash.Sum(append(0x01, append(left, right...)...))
+}
+
+// largest power of 2 less than k
+func getSplitPoint(k int) { ... }
+
+func MerkleRoot(items [][]byte) []byte{
+	switch len(items) {
+	case 0:
+		return nil
+	case 1:
+		return leafHash(leafs[0])
+	default:
+		k := getSplitPoint(len(items))
+		left := MerkleRoot(items[:k])
+		right := MerkleRoot(items[k:])
+		return innerHash(left, right)
+	}
 }
 ```
 
-Note that the leaves are Amino encoded as byte-arrays (ie. simple Uvarint length
-prefix) before being concatenated together and hashed.
+Note: `MerkleRoot` operates on items which are arbitrary byte arrays, not
+necessarily hashes. For items which need to be hashed first, we introduce the
+`Hashes` function:
+
+```
+func Hashes(items [][]byte) [][]byte {
+    return SHA256 of each item
+}
+```
 
-Note: we will abuse notion and invoke `SimpleMerkleRoot` with arguments of type `struct` or type `[]struct`.
-For `struct` arguments, we compute a `[][]byte` containing the hash of each
+Note: we will abuse notion and invoke `MerkleRoot` with arguments of type `struct` or type `[]struct`.
+For `struct` arguments, we compute a `[][]byte` containing the amino encoding of each
 field in the struct, in the same order the fields appear in the struct.
-For `[]struct` arguments, we compute a `[][]byte` by hashing the individual `struct` elements.
+For `[]struct` arguments, we compute a `[][]byte` by amino encoding the individual `struct` elements.
 
 ### Simple Merkle Proof
 
-Proof that a leaf is in a Merkle tree consists of a simple structure:
+Proof that a leaf is in a Merkle tree is composed as follows:
 
-```
+```golang
 type SimpleProof struct {
+        Total int
+        Index int
+        LeafHash []byte
         Aunts [][]byte
 }
 ```
 
-Which is verified using the following:
+Which is verified as follows:
 
-```
-func (proof SimpleProof) Verify(index, total int, leafHash, rootHash []byte) bool {
-	computedHash := computeHashFromAunts(index, total, leafHash, proof.Aunts)
+```golang
+func (proof SimpleProof) Verify(rootHash []byte, leaf []byte) bool {
+	assert(proof.LeafHash, leafHash(leaf)
+
+	computedHash := computeHashFromAunts(proof.Index, proof.Total, proof.LeafHash, proof.Aunts)
     return computedHash == rootHash
 }
 
@@ -238,26 +276,18 @@ func computeHashFromAunts(index, total int, leafHash []byte, innerHashes [][]byt
 
 	assert(len(innerHashes) > 0)
 
-	numLeft := (total + 1) / 2
+	numLeft := getSplitPoint(total) // largest power of 2 less than total
 	if index < numLeft {
 		leftHash := computeHashFromAunts(index, numLeft, leafHash, innerHashes[:len(innerHashes)-1])
 		assert(leftHash != nil)
-		return SimpleHashFromTwoHashes(leftHash, innerHashes[len(innerHashes)-1])
+		return innerHash(leftHash, innerHashes[len(innerHashes)-1])
 	}
 	rightHash := computeHashFromAunts(index-numLeft, total-numLeft, leafHash, innerHashes[:len(innerHashes)-1])
 	assert(rightHash != nil)
-	return SimpleHashFromTwoHashes(innerHashes[len(innerHashes)-1], rightHash)
+	return innerHash(innerHashes[len(innerHashes)-1], rightHash)
 }
 ```
 
-### Simple Tree with Dictionaries
-
-The Simple Tree is used to merkelize a list of items, so to merkelize a
-(short) dictionary of key-value pairs, encode the dictionary as an
-ordered list of `KVPair` structs. The block hash is such a hash
-derived from all the fields of the block `Header`. The state hash is
-similarly derived.
-
 ### IAVL+ Tree
 
 Because Tendermint only uses a Simple Merkle Tree, application developers are expect to use their own Merkle tree in their applications. For example, the IAVL+ Tree - an immutable self-balancing binary tree for persisting application state is used by the [Cosmos SDK](https://github.com/cosmos/cosmos-sdk/blob/develop/docs/sdk/core/multistore.md)
@@ -301,12 +331,14 @@ type CanonicalVote struct {
 	Type      byte
 	Height    int64            `binary:"fixed64"`
 	Round     int64            `binary:"fixed64"`
-	Timestamp time.Time
 	BlockID   CanonicalBlockID
+	Timestamp time.Time
 	ChainID   string
 }
 ```
 
 The field ordering and the fixed sized encoding for the first three fields is optimized to ease parsing of SignBytes
 in HSMs. It creates fixed offsets for relevant fields that need to be read in this context.
-See [#1622](https://github.com/tendermint/tendermint/issues/1622) for more details.
+For more details, see the [signing spec](/docs/spec/consensus/signing.md).
+Also, see the motivating discussion in
+[#1622](https://github.com/tendermint/tendermint/issues/1622).

docs/spec/blockchain/state.md

@@ -60,7 +60,7 @@ When hashing the Validator struct, the address is not included,
 because it is redundant with the pubkey.
 
 The `state.Validators`, `state.LastValidators`, and `state.NextValidators`, must always by sorted by validator address,
-so that there is a canonical order for computing the SimpleMerkleRoot.
+so that there is a canonical order for computing the MerkleRoot.
 
 We also define a `TotalVotingPower` function, to return the total voting power:
 
@@ -78,6 +78,8 @@ func TotalVotingPower(vals []Validators) int64{
 
 ConsensusParams define various limits for blockchain data structures.
 Like validator sets, they are set during genesis and can be updated by the application through ABCI.
+When hashed, only a subset of the params are included, to allow the params to
+evolve without breaking the header.
 
 ```go
 type ConsensusParams struct {
@@ -86,6 +88,18 @@ type ConsensusParams struct {
 	Validator
 }
 
+type hashedParams struct {
+    BlockMaxBytes int64
+    BlockMaxGas   int64
+}
+
+func (params ConsensusParams) Hash() []byte {
+    SHA256(hashedParams{
+        BlockMaxBytes: params.BlockSize.MaxBytes,
+        BlockMaxGas: params.BlockSize.MaxGas,
+    })
+}
+
 type BlockSize struct {
 	MaxBytes        int64
 	MaxGas          int64

docs/spec/consensus/signing.md

@@ -59,9 +59,9 @@ type PartSetHeader struct {
 ```
 
 To be included in a valid vote or proposal, BlockID must either represent a `nil` block, or a complete one.
-We introduce two methods, `BlockID.IsNil()` and `BlockID.IsComplete()` for these cases, respectively.
+We introduce two methods, `BlockID.IsZero()` and `BlockID.IsComplete()` for these cases, respectively.
 
-`BlockID.IsNil()` returns true for BlockID `b` if each of the following
+`BlockID.IsZero()` returns true for BlockID `b` if each of the following
 are true:
 
 ```
@@ -81,7 +81,7 @@ len(b.PartsHeader.Hash) == 32
 
 ## Proposals
 
-The structure of a propsal for signing looks like:
+The structure of a proposal for signing looks like:
 
 ```
 type CanonicalProposal struct {
@@ -118,8 +118,8 @@ type CanonicalVote struct {
 	Type      SignedMsgType // type alias for byte
 	Height    int64         `binary:"fixed64"`
 	Round     int64         `binary:"fixed64"`
-	Timestamp time.Time
 	BlockID   BlockID
+	Timestamp time.Time
 	ChainID   string
 }
 ```
@@ -130,7 +130,7 @@ A vote is valid if each of the following lines evaluates to true for vote `v`:
 v.Type == 0x1 || v.Type == 0x2
 v.Height > 0
 v.Round >= 0
-v.BlockID.IsNil() || v.BlockID.IsValid()
+v.BlockID.IsZero() || v.BlockID.IsComplete()
 ```
 
 In other words, a vote is valid for signing if it contains the type of a Prevote

libs/log/tmfmt_logger.go

@@ -90,7 +90,7 @@ func (l tmfmtLogger) Log(keyvals ...interface{}) error {
 	//     D										- first character of the level, uppercase (ASCII only)
 	//     [2016-05-02|11:06:44.322]    - our time format (see https://golang.org/src/time/format.go)
 	//     Stopping ...					- message
-	enc.buf.WriteString(fmt.Sprintf("%c[%s] %-44s ", lvl[0]-32, time.Now().Format("2016-01-02|15:04:05.000"), msg))
+	enc.buf.WriteString(fmt.Sprintf("%c[%s] %-44s ", lvl[0]-32, time.Now().Format("2006-01-02|15:04:05.000"), msg))
 
 	if module != unknown {
 		enc.buf.WriteString("module=" + module + " ")

lite/base_verifier.go

@@ -35,34 +35,40 @@ func NewBaseVerifier(chainID string, height int64, valset *types.ValidatorSet) *
 }
 
 // Implements Verifier.
-func (bc *BaseVerifier) ChainID() string {
-	return bc.chainID
+func (bv *BaseVerifier) ChainID() string {
+	return bv.chainID
 }
 
 // Implements Verifier.
-func (bc *BaseVerifier) Verify(signedHeader types.SignedHeader) error {
+func (bv *BaseVerifier) Verify(signedHeader types.SignedHeader) error {
 
-	// We can't verify commits older than bc.height.
-	if signedHeader.Height < bc.height {
+	// We can't verify commits for a different chain.
+	if signedHeader.ChainID != bv.chainID {
+		return cmn.NewError("BaseVerifier chainID is %v, cannot verify chainID %v",
+			bv.chainID, signedHeader.ChainID)
+	}
+
+	// We can't verify commits older than bv.height.
+	if signedHeader.Height < bv.height {
 		return cmn.NewError("BaseVerifier height is %v, cannot verify height %v",
-			bc.height, signedHeader.Height)
+			bv.height, signedHeader.Height)
 	}
 
 	// We can't verify with the wrong validator set.
 	if !bytes.Equal(signedHeader.ValidatorsHash,
-		bc.valset.Hash()) {
-		return lerr.ErrUnexpectedValidators(signedHeader.ValidatorsHash, bc.valset.Hash())
+		bv.valset.Hash()) {
+		return lerr.ErrUnexpectedValidators(signedHeader.ValidatorsHash, bv.valset.Hash())
 	}
 
 	// Do basic sanity checks.
-	err := signedHeader.ValidateBasic(bc.chainID)
+	err := signedHeader.ValidateBasic(bv.chainID)
 	if err != nil {
 		return cmn.ErrorWrap(err, "in verify")
 	}
 
 	// Check commit signatures.
-	err = bc.valset.VerifyCommit(
-		bc.chainID, signedHeader.Commit.BlockID,
+	err = bv.valset.VerifyCommit(
+		bv.chainID, signedHeader.Commit.BlockID,
 		signedHeader.Height, signedHeader.Commit)
 	if err != nil {
 		return cmn.ErrorWrap(err, "in verify")

lite/commit.go

@@ -8,7 +8,7 @@ import (
 	"github.com/tendermint/tendermint/types"
 )
 
-// FullCommit is a signed header (the block header and a commit that signs it),
+// FullCommit contains a SignedHeader (the block header and a commit that signs it),
 // the validator set which signed the commit, and the next validator set. The
 // next validator set (which is proven from the block header) allows us to
 // revert to block-by-block updating of lite Verifier's latest validator set,

lite/dbprovider.go

@@ -13,6 +13,9 @@ import (
 	"github.com/tendermint/tendermint/types"
 )
 
+var _ PersistentProvider = (*DBProvider)(nil)
+
+// DBProvider stores commits and validator sets in a DB.
 type DBProvider struct {
 	logger log.Logger
 	label  string

lite/doc.go

@@ -53,10 +53,6 @@ SignedHeader, and that the SignedHeader was to be signed by the exact given
 validator set, and that the height of the commit is at least height (or
 greater).
 
-SignedHeader.Commit may be signed by a different validator set, it can get
-verified with a BaseVerifier as long as sufficient signatures from the
-previous validator set are present in the commit.
-
 DynamicVerifier - this Verifier implements an auto-update and persistence
 strategy to verify any SignedHeader of the blockchain.
 

lite/dynamic_verifier.go

@@ -18,12 +18,17 @@ var _ Verifier = (*DynamicVerifier)(nil)
 // "source" provider to obtain the needed FullCommits to securely sync with
 // validator set changes.  It stores properly validated data on the
 // "trusted" local system.
+// TODO: make this single threaded and create a new
+// ConcurrentDynamicVerifier that wraps it with concurrency.
+// see https://github.com/tendermint/tendermint/issues/3170
 type DynamicVerifier struct {
-	logger  log.Logger
 	chainID string
-	// These are only properly validated data, from local system.
+	logger  log.Logger
+
+	// Already validated, stored locally
 	trusted PersistentProvider
-	// This is a source of new info, like a node rpc, or other import method.
+
+	// New info, like a node rpc, or other import method.
 	source Provider
 
 	// pending map to synchronize concurrent verification requests
@@ -35,8 +40,8 @@ type DynamicVerifier struct {
 // trusted provider to store validated data and the source provider to
 // obtain missing data (e.g. FullCommits).
 //
-// The trusted provider should a CacheProvider, MemProvider or
-// files.Provider.  The source provider should be a client.HTTPProvider.
+// The trusted provider should be a DBProvider.
+// The source provider should be a client.HTTPProvider.
 func NewDynamicVerifier(chainID string, trusted PersistentProvider, source Provider) *DynamicVerifier {
 	return &DynamicVerifier{
 		logger:               log.NewNopLogger(),
@@ -47,68 +52,71 @@ func NewDynamicVerifier(chainID string, trusted PersistentProvider, source Provi
 	}
 }
 
-func (ic *DynamicVerifier) SetLogger(logger log.Logger) {
+func (dv *DynamicVerifier) SetLogger(logger log.Logger) {
 	logger = logger.With("module", "lite")
-	ic.logger = logger
-	ic.trusted.SetLogger(logger)
-	ic.source.SetLogger(logger)
+	dv.logger = logger
+	dv.trusted.SetLogger(logger)
+	dv.source.SetLogger(logger)
 }
 
 // Implements Verifier.
-func (ic *DynamicVerifier) ChainID() string {
-	return ic.chainID
+func (dv *DynamicVerifier) ChainID() string {
+	return dv.chainID
 }
 
 // Implements Verifier.
 //
 // If the validators have changed since the last known time, it looks to
-// ic.trusted and ic.source to prove the new validators.  On success, it will
-// try to store the SignedHeader in ic.trusted if the next
+// dv.trusted and dv.source to prove the new validators.  On success, it will
+// try to store the SignedHeader in dv.trusted if the next
 // validator can be sourced.
-func (ic *DynamicVerifier) Verify(shdr types.SignedHeader) error {
+func (dv *DynamicVerifier) Verify(shdr types.SignedHeader) error {
 
 	// Performs synchronization for multi-threads verification at the same height.
-	ic.mtx.Lock()
-	if pending := ic.pendingVerifications[shdr.Height]; pending != nil {
-		ic.mtx.Unlock()
+	dv.mtx.Lock()
+	if pending := dv.pendingVerifications[shdr.Height]; pending != nil {
+		dv.mtx.Unlock()
 		<-pending // pending is chan struct{}
 	} else {
 		pending := make(chan struct{})
-		ic.pendingVerifications[shdr.Height] = pending
+		dv.pendingVerifications[shdr.Height] = pending
 		defer func() {
 			close(pending)
-			ic.mtx.Lock()
-			delete(ic.pendingVerifications, shdr.Height)
-			ic.mtx.Unlock()
+			dv.mtx.Lock()
+			delete(dv.pendingVerifications, shdr.Height)
+			dv.mtx.Unlock()
 		}()
-		ic.mtx.Unlock()
+		dv.mtx.Unlock()
 	}
+
 	//Get the exact trusted commit for h, and if it is
-	// equal to shdr, then don't even verify it,
-	// and just return nil.
-	trustedFCSameHeight, err := ic.trusted.LatestFullCommit(ic.chainID, shdr.Height, shdr.Height)
+	// equal to shdr, then it's already trusted, so
+	// just return nil.
+	trustedFCSameHeight, err := dv.trusted.LatestFullCommit(dv.chainID, shdr.Height, shdr.Height)
 	if err == nil {
 		// If loading trust commit successfully, and trust commit equal to shdr, then don't verify it,
 		// just return nil.
 		if bytes.Equal(trustedFCSameHeight.SignedHeader.Hash(), shdr.Hash()) {
-			ic.logger.Info(fmt.Sprintf("Load full commit at height %d from cache, there is not need to verify.", shdr.Height))
+			dv.logger.Info(fmt.Sprintf("Load full commit at height %d from cache, there is not need to verify.", shdr.Height))
 			return nil
 		}
 	} else if !lerr.IsErrCommitNotFound(err) {
 		// Return error if it is not CommitNotFound error
-		ic.logger.Info(fmt.Sprintf("Encountered unknown error in loading full commit at height %d.", shdr.Height))
+		dv.logger.Info(fmt.Sprintf("Encountered unknown error in loading full commit at height %d.", shdr.Height))
 		return err
 	}
 
 	// Get the latest known full commit <= h-1 from our trusted providers.
 	// The full commit at h-1 contains the valset to sign for h.
-	h := shdr.Height - 1
-	trustedFC, err := ic.trusted.LatestFullCommit(ic.chainID, 1, h)
+	prevHeight := shdr.Height - 1
+	trustedFC, err := dv.trusted.LatestFullCommit(dv.chainID, 1, prevHeight)
 	if err != nil {
 		return err
 	}
 
-	if trustedFC.Height() == h {
+	// sync up to the prevHeight and assert our latest NextValidatorSet
+	// is the ValidatorSet for the SignedHeader
+	if trustedFC.Height() == prevHeight {
 		// Return error if valset doesn't match.
 		if !bytes.Equal(
 			trustedFC.NextValidators.Hash(),
@@ -118,11 +126,12 @@ func (ic *DynamicVerifier) Verify(shdr types.SignedHeader) error {
 				shdr.Header.ValidatorsHash)
 		}
 	} else {
-		// If valset doesn't match...
-		if !bytes.Equal(trustedFC.NextValidators.Hash(),
+		// If valset doesn't match, try to update
+		if !bytes.Equal(
+			trustedFC.NextValidators.Hash(),
 			shdr.Header.ValidatorsHash) {
 			// ... update.
-			trustedFC, err = ic.updateToHeight(h)
+			trustedFC, err = dv.updateToHeight(prevHeight)
 			if err != nil {
 				return err
 			}
@@ -137,14 +146,21 @@ func (ic *DynamicVerifier) Verify(shdr types.SignedHeader) error {
 	}
 
 	// Verify the signed header using the matching valset.
-	cert := NewBaseVerifier(ic.chainID, trustedFC.Height()+1, trustedFC.NextValidators)
+	cert := NewBaseVerifier(dv.chainID, trustedFC.Height()+1, trustedFC.NextValidators)
 	err = cert.Verify(shdr)
 	if err != nil {
 		return err
 	}
 
+	// By now, the SignedHeader is fully validated and we're synced up to
+	// SignedHeader.Height - 1. To sync to SignedHeader.Height, we need
+	// the validator set at SignedHeader.Height + 1 so we can verify the
+	// SignedHeader.NextValidatorSet.
+	// TODO: is the ValidateFull below mostly redundant with the BaseVerifier.Verify above?
+	// See https://github.com/tendermint/tendermint/issues/3174.
+
 	// Get the next validator set.
-	nextValset, err := ic.source.ValidatorSet(ic.chainID, shdr.Height+1)
+	nextValset, err := dv.source.ValidatorSet(dv.chainID, shdr.Height+1)
 	if lerr.IsErrUnknownValidators(err) {
 		// Ignore this error.
 		return nil
@@ -160,31 +176,31 @@ func (ic *DynamicVerifier) Verify(shdr types.SignedHeader) error {
 	}
 	// Validate the full commit.  This checks the cryptographic
 	// signatures of Commit against Validators.
-	if err := nfc.ValidateFull(ic.chainID); err != nil {
+	if err := nfc.ValidateFull(dv.chainID); err != nil {
 		return err
 	}
 	// Trust it.
-	return ic.trusted.SaveFullCommit(nfc)
+	return dv.trusted.SaveFullCommit(nfc)
 }
 
 // verifyAndSave will verify if this is a valid source full commit given the
-// best match trusted full commit, and if good, persist to ic.trusted.
+// best match trusted full commit, and if good, persist to dv.trusted.
 // Returns ErrTooMuchChange when >2/3 of trustedFC did not sign sourceFC.
 // Panics if trustedFC.Height() >= sourceFC.Height().
-func (ic *DynamicVerifier) verifyAndSave(trustedFC, sourceFC FullCommit) error {
+func (dv *DynamicVerifier) verifyAndSave(trustedFC, sourceFC FullCommit) error {
 	if trustedFC.Height() >= sourceFC.Height() {
 		panic("should not happen")
 	}
 	err := trustedFC.NextValidators.VerifyFutureCommit(
 		sourceFC.Validators,
-		ic.chainID, sourceFC.SignedHeader.Commit.BlockID,
+		dv.chainID, sourceFC.SignedHeader.Commit.BlockID,
 		sourceFC.SignedHeader.Height, sourceFC.SignedHeader.Commit,
 	)
 	if err != nil {
 		return err
 	}
 
-	return ic.trusted.SaveFullCommit(sourceFC)
+	return dv.trusted.SaveFullCommit(sourceFC)
 }
 
 // updateToHeight will use divide-and-conquer to find a path to h.
@@ -192,29 +208,30 @@ func (ic *DynamicVerifier) verifyAndSave(trustedFC, sourceFC FullCommit) error {
 // for height h, using repeated applications of bisection if necessary.
 //
 // Returns ErrCommitNotFound if source provider doesn't have the commit for h.
-func (ic *DynamicVerifier) updateToHeight(h int64) (FullCommit, error) {
+func (dv *DynamicVerifier) updateToHeight(h int64) (FullCommit, error) {
 
 	// Fetch latest full commit from source.
-	sourceFC, err := ic.source.LatestFullCommit(ic.chainID, h, h)
+	sourceFC, err := dv.source.LatestFullCommit(dv.chainID, h, h)
 	if err != nil {
 		return FullCommit{}, err
 	}
 
-	// Validate the full commit.  This checks the cryptographic
-	// signatures of Commit against Validators.
-	if err := sourceFC.ValidateFull(ic.chainID); err != nil {
-		return FullCommit{}, err
-	}
-
 	// If sourceFC.Height() != h, we can't do it.
 	if sourceFC.Height() != h {
 		return FullCommit{}, lerr.ErrCommitNotFound()
 	}
 
+	// Validate the full commit.  This checks the cryptographic
+	// signatures of Commit against Validators.
+	if err := sourceFC.ValidateFull(dv.chainID); err != nil {
+		return FullCommit{}, err
+	}
+
+	// Verify latest FullCommit against trusted FullCommits
 FOR_LOOP:
 	for {
 		// Fetch latest full commit from trusted.
-		trustedFC, err := ic.trusted.LatestFullCommit(ic.chainID, 1, h)
+		trustedFC, err := dv.trusted.LatestFullCommit(dv.chainID, 1, h)
 		if err != nil {
 			return FullCommit{}, err
 		}
@@ -224,21 +241,21 @@ FOR_LOOP:
 		}
 
 		// Try to update to full commit with checks.
-		err = ic.verifyAndSave(trustedFC, sourceFC)
+		err = dv.verifyAndSave(trustedFC, sourceFC)
 		if err == nil {
 			// All good!
 			return sourceFC, nil
 		}
 
 		// Handle special case when err is ErrTooMuchChange.
-		if lerr.IsErrTooMuchChange(err) {
+		if types.IsErrTooMuchChange(err) {
 			// Divide and conquer.
 			start, end := trustedFC.Height(), sourceFC.Height()
 			if !(start < end) {
 				panic("should not happen")
 			}
 			mid := (start + end) / 2
-			_, err = ic.updateToHeight(mid)
+			_, err = dv.updateToHeight(mid)
 			if err != nil {
 				return FullCommit{}, err
 			}
@@ -249,8 +266,8 @@ FOR_LOOP:
 	}
 }
 
-func (ic *DynamicVerifier) LastTrustedHeight() int64 {
-	fc, err := ic.trusted.LatestFullCommit(ic.chainID, 1, 1<<63-1)
+func (dv *DynamicVerifier) LastTrustedHeight() int64 {
+	fc, err := dv.trusted.LatestFullCommit(dv.chainID, 1, 1<<63-1)
 	if err != nil {
 		panic("should not happen")
 	}

lite/dynamic_verifier_test.go

@@ -10,6 +10,7 @@ import (
 
 	dbm "github.com/tendermint/tendermint/libs/db"
 	log "github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/types"
 )
 
 func TestInquirerValidPath(t *testing.T) {
@@ -70,6 +71,70 @@ func TestInquirerValidPath(t *testing.T) {
 	assert.Nil(err, "%+v", err)
 }
 
+func TestDynamicVerify(t *testing.T) {
+	trust := NewDBProvider("trust", dbm.NewMemDB())
+	source := NewDBProvider("source", dbm.NewMemDB())
+
+	// 10 commits with one valset, 1 to change,
+	// 10 commits with the next one
+	n1, n2 := 10, 10
+	nCommits := n1 + n2 + 1
+	maxHeight := int64(nCommits)
+	fcz := make([]FullCommit, nCommits)
+
+	// gen the 2 val sets
+	chainID := "dynamic-verifier"
+	power := int64(10)
+	keys1 := genPrivKeys(5)
+	vals1 := keys1.ToValidators(power, 0)
+	keys2 := genPrivKeys(5)
+	vals2 := keys2.ToValidators(power, 0)
+
+	// make some commits with the first
+	for i := 0; i < n1; i++ {
+		fcz[i] = makeFullCommit(int64(i), keys1, vals1, vals1, chainID)
+	}
+
+	// update the val set
+	fcz[n1] = makeFullCommit(int64(n1), keys1, vals1, vals2, chainID)
+
+	// make some commits with the new one
+	for i := n1 + 1; i < nCommits; i++ {
+		fcz[i] = makeFullCommit(int64(i), keys2, vals2, vals2, chainID)
+	}
+
+	// Save everything in the source
+	for _, fc := range fcz {
+		source.SaveFullCommit(fc)
+	}
+
+	// Initialize a Verifier with the initial state.
+	err := trust.SaveFullCommit(fcz[0])
+	require.Nil(t, err)
+	ver := NewDynamicVerifier(chainID, trust, source)
+	ver.SetLogger(log.TestingLogger())
+
+	// fetch the latest from the source
+	latestFC, err := source.LatestFullCommit(chainID, 1, maxHeight)
+	require.NoError(t, err)
+
+	// try to update to the latest
+	err = ver.Verify(latestFC.SignedHeader)
+	require.NoError(t, err)
+
+}
+
+func makeFullCommit(height int64, keys privKeys, vals, nextVals *types.ValidatorSet, chainID string) FullCommit {
+	height += 1
+	consHash := []byte("special-params")
+	appHash := []byte(fmt.Sprintf("h=%d", height))
+	resHash := []byte(fmt.Sprintf("res=%d", height))
+	return keys.GenFullCommit(
+		chainID, height, nil,
+		vals, nextVals,
+		appHash, consHash, resHash, 0, len(keys))
+}
+
 func TestInquirerVerifyHistorical(t *testing.T) {
 	assert, require := assert.New(t), require.New(t)
 	trust := NewDBProvider("trust", dbm.NewMemDB())

lite/errors/errors.go

@@ -25,12 +25,6 @@ func (e errUnexpectedValidators) Error() string {
 		e.got, e.want)
 }
 
-type errTooMuchChange struct{}
-
-func (e errTooMuchChange) Error() string {
-	return "Insufficient signatures to validate due to valset changes"
-}
-
 type errUnknownValidators struct {
 	chainID string
 	height  int64
@@ -85,22 +79,6 @@ func IsErrUnexpectedValidators(err error) bool {
 	return false
 }
 
-//-----------------
-// ErrTooMuchChange
-
-// ErrTooMuchChange indicates that the underlying validator set was changed by >1/3.
-func ErrTooMuchChange() error {
-	return cmn.ErrorWrap(errTooMuchChange{}, "")
-}
-
-func IsErrTooMuchChange(err error) bool {
-	if err_, ok := err.(cmn.Error); ok {
-		_, ok := err_.Data().(errTooMuchChange)
-		return ok
-	}
-	return false
-}
-
 //-----------------
 // ErrUnknownValidators
 

lite/multiprovider.go

@@ -6,6 +6,8 @@ import (
 	"github.com/tendermint/tendermint/types"
 )
 
+var _ PersistentProvider = (*multiProvider)(nil)
+
 // multiProvider allows you to place one or more caches in front of a source
 // Provider.  It runs through them in order until a match is found.
 type multiProvider struct {

lite/provider.go

@@ -1,7 +1,7 @@
 package lite
 
 import (
-	log "github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/libs/log"
 	"github.com/tendermint/tendermint/types"
 )
 

lite/proxy/query_test.go

@@ -10,6 +10,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/tendermint/tendermint/abci/example/kvstore"
+	"github.com/tendermint/tendermint/crypto/merkle"
 	"github.com/tendermint/tendermint/lite"
 	certclient "github.com/tendermint/tendermint/lite/client"
 	nm "github.com/tendermint/tendermint/node"
@@ -143,12 +144,13 @@ func TestTxProofs(t *testing.T) {
 	require.NotNil(err)
 	require.Contains(err.Error(), "not found")
 
-	// Now let's check with the real tx hash.
+	// Now let's check with the real tx root hash.
 	key = types.Tx(tx).Hash()
 	res, err = cl.Tx(key, true)
 	require.NoError(err, "%#v", err)
 	require.NotNil(res)
-	err = res.Proof.Validate(key)
+	keyHash := merkle.SimpleHashFromByteSlices([][]byte{key})
+	err = res.Proof.Validate(keyHash)
 	assert.NoError(err, "%#v", err)
 
 	commit, err := GetCertifiedCommit(br.Height, cl, cert)

mempool/mempool.go

@@ -65,6 +65,9 @@ var (
 
 	// ErrMempoolIsFull means Tendermint & an application can't handle that much load
 	ErrMempoolIsFull = errors.New("Mempool is full")
+
+	// ErrTxTooLarge means the tx is too big to be sent in a message to other peers
+	ErrTxTooLarge = fmt.Errorf("Tx too large. Max size is %d", maxTxSize)
 )
 
 // ErrPreCheck is returned when tx is too big
@@ -309,6 +312,13 @@ func (mem *Mempool) CheckTx(tx types.Tx, cb func(*abci.Response)) (err error) {
 		return ErrMempoolIsFull
 	}
 
+	// The size of the corresponding amino-encoded TxMessage
+	// can't be larger than the maxMsgSize, otherwise we can't
+	// relay it to peers.
+	if len(tx) > maxTxSize {
+		return ErrTxTooLarge
+	}
+
 	if mem.preCheck != nil {
 		if err := mem.preCheck(tx); err != nil {
 			return ErrPreCheck{err}

mempool/mempool_test.go

@@ -14,10 +14,12 @@ import (
 	"github.com/stretchr/testify/assert"
 
 	"github.com/stretchr/testify/require"
+	amino "github.com/tendermint/go-amino"
 	"github.com/tendermint/tendermint/abci/example/counter"
 	"github.com/tendermint/tendermint/abci/example/kvstore"
 	abci "github.com/tendermint/tendermint/abci/types"
 	cfg "github.com/tendermint/tendermint/config"
+	cmn "github.com/tendermint/tendermint/libs/common"
 	"github.com/tendermint/tendermint/libs/log"
 	"github.com/tendermint/tendermint/proxy"
 	"github.com/tendermint/tendermint/types"
@@ -394,6 +396,60 @@ func TestMempoolCloseWAL(t *testing.T) {
 	require.Equal(t, 1, len(m3), "expecting the wal match in")
 }
 
+// Size of the amino encoded TxMessage is the length of the
+// encoded byte array, plus 1 for the struct field, plus 4
+// for the amino prefix.
+func txMessageSize(tx types.Tx) int {
+	return amino.ByteSliceSize(tx) + 1 + 4
+}
+
+func TestMempoolMaxMsgSize(t *testing.T) {
+	app := kvstore.NewKVStoreApplication()
+	cc := proxy.NewLocalClientCreator(app)
+	mempl := newMempoolWithApp(cc)
+
+	testCases := []struct {
+		len int
+		err bool
+	}{
+		// check small txs. no error
+		{10, false},
+		{1000, false},
+		{1000000, false},
+
+		// check around maxTxSize
+		// changes from no error to error
+		{maxTxSize - 2, false},
+		{maxTxSize - 1, false},
+		{maxTxSize, false},
+		{maxTxSize + 1, true},
+		{maxTxSize + 2, true},
+
+		// check around maxMsgSize. all error
+		{maxMsgSize - 1, true},
+		{maxMsgSize, true},
+		{maxMsgSize + 1, true},
+	}
+
+	for i, testCase := range testCases {
+		caseString := fmt.Sprintf("case %d, len %d", i, testCase.len)
+
+		tx := cmn.RandBytes(testCase.len)
+		err := mempl.CheckTx(tx, nil)
+		msg := &TxMessage{tx}
+		encoded := cdc.MustMarshalBinaryBare(msg)
+		require.Equal(t, len(encoded), txMessageSize(tx), caseString)
+		if !testCase.err {
+			require.True(t, len(encoded) <= maxMsgSize, caseString)
+			require.NoError(t, err, caseString)
+		} else {
+			require.True(t, len(encoded) > maxMsgSize, caseString)
+			require.Equal(t, err, ErrTxTooLarge, caseString)
+		}
+	}
+
+}
+
 func checksumIt(data []byte) string {
 	h := md5.New()
 	h.Write(data)

mempool/metrics.go

@@ -7,7 +7,11 @@ import (
 	stdprometheus "github.com/prometheus/client_golang/prometheus"
 )
 
-const MetricsSubsytem = "mempool"
+const (
+	// MetricsSubsystem is a subsystem shared by all metrics exposed by this
+	// package.
+	MetricsSubsystem = "mempool"
+)
 
 // Metrics contains metrics exposed by this package.
 // see MetricsProvider for descriptions.
@@ -23,33 +27,39 @@ type Metrics struct {
 }
 
 // PrometheusMetrics returns Metrics build using Prometheus client library.
-func PrometheusMetrics(namespace string) *Metrics {
+// Optionally, labels can be provided along with their values ("foo",
+// "fooValue").
+func PrometheusMetrics(namespace string, labelsAndValues ...string) *Metrics {
+	labels := []string{}
+	for i := 0; i < len(labelsAndValues); i += 2 {
+		labels = append(labels, labelsAndValues[i])
+	}
 	return &Metrics{
 		Size: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
-			Subsystem: MetricsSubsytem,
+			Subsystem: MetricsSubsystem,
 			Name:      "size",
 			Help:      "Size of the mempool (number of uncommitted transactions).",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		TxSizeBytes: prometheus.NewHistogramFrom(stdprometheus.HistogramOpts{
 			Namespace: namespace,
-			Subsystem: MetricsSubsytem,
+			Subsystem: MetricsSubsystem,
 			Name:      "tx_size_bytes",
 			Help:      "Transaction sizes in bytes.",
 			Buckets:   stdprometheus.ExponentialBuckets(1, 3, 17),
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		FailedTxs: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
 			Namespace: namespace,
-			Subsystem: MetricsSubsytem,
+			Subsystem: MetricsSubsystem,
 			Name:      "failed_txs",
 			Help:      "Number of failed transactions.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		RecheckTimes: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
 			Namespace: namespace,
-			Subsystem: MetricsSubsytem,
+			Subsystem: MetricsSubsystem,
 			Name:      "recheck_times",
 			Help:      "Number of times transactions are rechecked in the mempool.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 	}
 }
 

mempool/reactor.go

@@ -6,7 +6,6 @@ import (
 	"time"
 
 	amino "github.com/tendermint/go-amino"
-	abci "github.com/tendermint/tendermint/abci/types"
 	"github.com/tendermint/tendermint/libs/clist"
 	"github.com/tendermint/tendermint/libs/log"
 
@@ -18,8 +17,10 @@ import (
 const (
 	MempoolChannel = byte(0x30)
 
-	maxMsgSize                 = 1048576 // 1MB TODO make it configurable
-	peerCatchupSleepIntervalMS = 100     // If peer is behind, sleep this amount
+	maxMsgSize = 1048576        // 1MB TODO make it configurable
+	maxTxSize  = maxMsgSize - 8 // account for amino overhead of TxMessage
+
+	peerCatchupSleepIntervalMS = 100 // If peer is behind, sleep this amount
 )
 
 // MempoolReactor handles mempool tx broadcasting amongst peers.
@@ -98,11 +99,6 @@ func (memR *MempoolReactor) Receive(chID byte, src p2p.Peer, msgBytes []byte) {
 	}
 }
 
-// BroadcastTx is an alias for Mempool.CheckTx. Broadcasting itself happens in peer routines.
-func (memR *MempoolReactor) BroadcastTx(tx types.Tx, cb func(*abci.Response)) error {
-	return memR.Mempool.CheckTx(tx, cb)
-}
-
 // PeerState describes the state of a peer.
 type PeerState interface {
 	GetHeight() int64

node/node.go

@@ -117,15 +117,17 @@ func DefaultNewNode(config *cfg.Config, logger log.Logger) (*Node, error) {
 }
 
 // MetricsProvider returns a consensus, p2p and mempool Metrics.
-type MetricsProvider func() (*cs.Metrics, *p2p.Metrics, *mempl.Metrics, *sm.Metrics)
+type MetricsProvider func(chainID string) (*cs.Metrics, *p2p.Metrics, *mempl.Metrics, *sm.Metrics)
 
 // DefaultMetricsProvider returns Metrics build using Prometheus client library
 // if Prometheus is enabled. Otherwise, it returns no-op Metrics.
 func DefaultMetricsProvider(config *cfg.InstrumentationConfig) MetricsProvider {
-	return func() (*cs.Metrics, *p2p.Metrics, *mempl.Metrics, *sm.Metrics) {
+	return func(chainID string) (*cs.Metrics, *p2p.Metrics, *mempl.Metrics, *sm.Metrics) {
 		if config.Prometheus {
-			return cs.PrometheusMetrics(config.Namespace), p2p.PrometheusMetrics(config.Namespace),
-				mempl.PrometheusMetrics(config.Namespace), sm.PrometheusMetrics(config.Namespace)
+			return cs.PrometheusMetrics(config.Namespace, "chain_id", chainID),
+				p2p.PrometheusMetrics(config.Namespace, "chain_id", chainID),
+				mempl.PrometheusMetrics(config.Namespace, "chain_id", chainID),
+				sm.PrometheusMetrics(config.Namespace, "chain_id", chainID)
 		}
 		return cs.NopMetrics(), p2p.NopMetrics(), mempl.NopMetrics(), sm.NopMetrics()
 	}
@@ -274,7 +276,7 @@ func NewNode(config *cfg.Config,
 		consensusLogger.Info("This node is not a validator", "addr", addr, "pubKey", pubKey)
 	}
 
-	csMetrics, p2pMetrics, memplMetrics, smMetrics := metricsProvider()
+	csMetrics, p2pMetrics, memplMetrics, smMetrics := metricsProvider(genDoc.ChainID)
 
 	// Make MempoolReactor
 	mempool := mempl.NewMempool(

p2p/metrics.go

@@ -7,7 +7,11 @@ import (
 	stdprometheus "github.com/prometheus/client_golang/prometheus"
 )
 
-const MetricsSubsystem = "p2p"
+const (
+	// MetricsSubsystem is a subsystem shared by all metrics exposed by this
+	// package.
+	MetricsSubsystem = "p2p"
+)
 
 // Metrics contains metrics exposed by this package.
 type Metrics struct {
@@ -24,45 +28,51 @@ type Metrics struct {
 }
 
 // PrometheusMetrics returns Metrics build using Prometheus client library.
-func PrometheusMetrics(namespace string) *Metrics {
+// Optionally, labels can be provided along with their values ("foo",
+// "fooValue").
+func PrometheusMetrics(namespace string, labelsAndValues ...string) *Metrics {
+	labels := []string{}
+	for i := 0; i < len(labelsAndValues); i += 2 {
+		labels = append(labels, labelsAndValues[i])
+	}
 	return &Metrics{
 		Peers: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "peers",
 			Help:      "Number of peers.",
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 		PeerReceiveBytesTotal: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "peer_receive_bytes_total",
 			Help:      "Number of bytes received from a given peer.",
-		}, []string{"peer_id"}),
+		}, append(labels, "peer_id")).With(labelsAndValues...),
 		PeerSendBytesTotal: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "peer_send_bytes_total",
 			Help:      "Number of bytes sent to a given peer.",
-		}, []string{"peer_id"}),
+		}, append(labels, "peer_id")).With(labelsAndValues...),
 		PeerPendingSendBytes: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "peer_pending_send_bytes",
 			Help:      "Number of pending bytes to be sent to a given peer.",
-		}, []string{"peer_id"}),
+		}, append(labels, "peer_id")).With(labelsAndValues...),
 		NumTxs: prometheus.NewGaugeFrom(stdprometheus.GaugeOpts{
 			Namespace: namespace,
 			Subsystem: MetricsSubsystem,
 			Name:      "num_txs",
 			Help:      "Number of transactions submitted by each peer.",
-		}, []string{"peer_id"}),
+		}, append(labels, "peer_id")).With(labelsAndValues...),
 	}
 }
 
 // NopMetrics returns no-op Metrics.
 func NopMetrics() *Metrics {
 	return &Metrics{
-		Peers: discard.NewGauge(),
+		Peers:                 discard.NewGauge(),
 		PeerReceiveBytesTotal: discard.NewCounter(),
 		PeerSendBytesTotal:    discard.NewCounter(),
 		PeerPendingSendBytes:  discard.NewGauge(),

privval/client_test.go

@@ -13,7 +13,6 @@ import (
 	cmn "github.com/tendermint/tendermint/libs/common"
 	"github.com/tendermint/tendermint/libs/log"
 
-	p2pconn "github.com/tendermint/tendermint/p2p/conn"
 	"github.com/tendermint/tendermint/types"
 )
 
@@ -186,40 +185,36 @@ func TestSocketPVVoteKeepalive(t *testing.T) {
 	}
 }
 
-// TestSocketPVDeadlineTCPOnly is not relevant to Unix domain sockets, since the
-// OS knows instantaneously the state of both sides of the connection.
-func TestSocketPVDeadlineTCPOnly(t *testing.T) {
-	var (
-		addr            = testFreeTCPAddr(t)
-		listenc         = make(chan struct{})
-		thisConnTimeout = 100 * time.Millisecond
-		sc              = newSocketVal(log.TestingLogger(), addr, thisConnTimeout)
-	)
+func TestSocketPVDeadline(t *testing.T) {
+	for _, tc := range socketTestCases(t) {
+		func() {
+			var (
+				listenc         = make(chan struct{})
+				thisConnTimeout = 100 * time.Millisecond
+				sc              = newSocketVal(log.TestingLogger(), tc.addr, thisConnTimeout)
+			)
 
-	go func(sc *SocketVal) {
-		defer close(listenc)
+			go func(sc *SocketVal) {
+				defer close(listenc)
 
-		assert.Equal(t, sc.Start().(cmn.Error).Data(), ErrConnTimeout)
+				// Note: the TCP connection times out at the accept() phase,
+				// whereas the Unix domain sockets connection times out while
+				// attempting to fetch the remote signer's public key.
+				assert.True(t, IsConnTimeout(sc.Start()))
 
-		assert.False(t, sc.IsRunning())
-	}(sc)
+				assert.False(t, sc.IsRunning())
+			}(sc)
 
-	for {
-		conn, err := cmn.Connect(addr)
-		if err != nil {
-			continue
-		}
+			for {
+				_, err := cmn.Connect(tc.addr)
+				if err == nil {
+					break
+				}
+			}
 
-		_, err = p2pconn.MakeSecretConnection(
-			conn,
-			ed25519.GenPrivKey(),
-		)
-		if err == nil {
-			break
-		}
+			<-listenc
+		}()
 	}
-
-	<-listenc
 }
 
 func TestRemoteSignVoteErrors(t *testing.T) {

privval/remote_signer.go

@@ -258,3 +258,18 @@ func handleRequest(req RemoteSignerMsg, chainID string, privVal types.PrivValida
 
 	return res, err
 }
+
+// IsConnTimeout returns a boolean indicating whether the error is known to
+// report that a connection timeout occurred. This detects both fundamental
+// network timeouts, as well as ErrConnTimeout errors.
+func IsConnTimeout(err error) bool {
+	if cmnErr, ok := err.(cmn.Error); ok {
+		if cmnErr.Data() == ErrConnTimeout {
+			return true
+		}
+	}
+	if _, ok := err.(timeoutError); ok {
+		return true
+	}
+	return false
+}

privval/remote_signer_test.go

@@ -5,6 +5,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/pkg/errors"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/tendermint/tendermint/crypto/ed25519"
@@ -66,3 +67,24 @@ func TestRemoteSignerRetryTCPOnly(t *testing.T) {
 		t.Error("expected remote to observe connection attempts")
 	}
 }
+
+func TestIsConnTimeoutForFundamentalTimeouts(t *testing.T) {
+	// Generate a networking timeout
+	dialer := DialTCPFn(testFreeTCPAddr(t), time.Millisecond, ed25519.GenPrivKey())
+	_, err := dialer()
+	assert.Error(t, err)
+	assert.True(t, IsConnTimeout(err))
+}
+
+func TestIsConnTimeoutForWrappedConnTimeouts(t *testing.T) {
+	dialer := DialTCPFn(testFreeTCPAddr(t), time.Millisecond, ed25519.GenPrivKey())
+	_, err := dialer()
+	assert.Error(t, err)
+	err = cmn.ErrorWrap(ErrConnTimeout, err.Error())
+	assert.True(t, IsConnTimeout(err))
+}
+
+func TestIsConnTimeoutForNonTimeoutErrors(t *testing.T) {
+	assert.False(t, IsConnTimeout(cmn.ErrorWrap(ErrDialRetryMax, "max retries exceeded")))
+	assert.False(t, IsConnTimeout(errors.New("completely irrelevant error")))
+}

rpc/core/pipe.go

@@ -149,8 +149,10 @@ func validatePage(page, perPage, totalCount int) int {
 }
 
 func validatePerPage(perPage int) int {
-	if perPage < 1 || perPage > maxPerPage {
+	if perPage < 1 {
 		return defaultPerPage
+	} else if perPage > maxPerPage {
+		return maxPerPage
 	}
 	return perPage
 }

rpc/core/pipe_test.go

@@ -47,7 +47,6 @@ func TestPaginationPage(t *testing.T) {
 }
 
 func TestPaginationPerPage(t *testing.T) {
-
 	cases := []struct {
 		totalCount int
 		perPage    int
@@ -59,7 +58,7 @@ func TestPaginationPerPage(t *testing.T) {
 		{5, defaultPerPage, defaultPerPage},
 		{5, maxPerPage - 1, maxPerPage - 1},
 		{5, maxPerPage, maxPerPage},
-		{5, maxPerPage + 1, defaultPerPage},
+		{5, maxPerPage + 1, maxPerPage},
 	}
 
 	for _, c := range cases {

scripts/json2wal/main.go

@@ -45,7 +45,10 @@ func main() {
 	}
 	defer walFile.Close()
 
-	br := bufio.NewReader(f)
+	// the length of tendermint/wal/MsgInfo in the wal.json may exceed the defaultBufSize(4096) of bufio
+	// because of the byte array in BlockPart
+	// leading to unmarshal error: unexpected end of JSON input
+	br := bufio.NewReaderSize(f, 2*types.BlockPartSizeBytes)
 	dec := cs.NewWALEncoder(walFile)
 
 	for {

state/metrics.go

@@ -7,14 +7,26 @@ import (
 	stdprometheus "github.com/prometheus/client_golang/prometheus"
 )
 
-const MetricsSubsystem = "state"
+const (
+	// MetricsSubsystem is a subsystem shared by all metrics exposed by this
+	// package.
+	MetricsSubsystem = "state"
+)
 
+// Metrics contains metrics exposed by this package.
 type Metrics struct {
 	// Time between BeginBlock and EndBlock.
 	BlockProcessingTime metrics.Histogram
 }
 
-func PrometheusMetrics(namespace string) *Metrics {
+// PrometheusMetrics returns Metrics build using Prometheus client library.
+// Optionally, labels can be provided along with their values ("foo",
+// "fooValue").
+func PrometheusMetrics(namespace string, labelsAndValues ...string) *Metrics {
+	labels := []string{}
+	for i := 0; i < len(labelsAndValues); i += 2 {
+		labels = append(labels, labelsAndValues[i])
+	}
 	return &Metrics{
 		BlockProcessingTime: prometheus.NewHistogramFrom(stdprometheus.HistogramOpts{
 			Namespace: namespace,
@@ -22,10 +34,11 @@ func PrometheusMetrics(namespace string) *Metrics {
 			Name:      "block_processing_time",
 			Help:      "Time between BeginBlock and EndBlock in ms.",
 			Buckets:   stdprometheus.LinearBuckets(1, 10, 10),
-		}, []string{}),
+		}, labels).With(labelsAndValues...),
 	}
 }
 
+// NopMetrics returns no-op Metrics.
 func NopMetrics() *Metrics {
 	return &Metrics{
 		BlockProcessingTime: discard.NewHistogram(),

state/state_test.go

@@ -3,6 +3,8 @@ package state
 import (
 	"bytes"
 	"fmt"
+	"math"
+	"math/big"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -263,6 +265,511 @@ func TestOneValidatorChangesSaveLoad(t *testing.T) {
 	}
 }
 
+func TestProposerFrequency(t *testing.T) {
+
+	// some explicit test cases
+	testCases := []struct {
+		powers []int64
+	}{
+		// 2 vals
+		{[]int64{1, 1}},
+		{[]int64{1, 2}},
+		{[]int64{1, 100}},
+		{[]int64{5, 5}},
+		{[]int64{5, 100}},
+		{[]int64{50, 50}},
+		{[]int64{50, 100}},
+		{[]int64{1, 1000}},
+
+		// 3 vals
+		{[]int64{1, 1, 1}},
+		{[]int64{1, 2, 3}},
+		{[]int64{1, 2, 3}},
+		{[]int64{1, 1, 10}},
+		{[]int64{1, 1, 100}},
+		{[]int64{1, 10, 100}},
+		{[]int64{1, 1, 1000}},
+		{[]int64{1, 10, 1000}},
+		{[]int64{1, 100, 1000}},
+
+		// 4 vals
+		{[]int64{1, 1, 1, 1}},
+		{[]int64{1, 2, 3, 4}},
+		{[]int64{1, 1, 1, 10}},
+		{[]int64{1, 1, 1, 100}},
+		{[]int64{1, 1, 1, 1000}},
+		{[]int64{1, 1, 10, 100}},
+		{[]int64{1, 1, 10, 1000}},
+		{[]int64{1, 1, 100, 1000}},
+		{[]int64{1, 10, 100, 1000}},
+	}
+
+	for caseNum, testCase := range testCases {
+		// run each case 5 times to sample different
+		// initial priorities
+		for i := 0; i < 5; i++ {
+			valSet := genValSetWithPowers(testCase.powers)
+			testProposerFreq(t, caseNum, valSet)
+		}
+	}
+
+	// some random test cases with up to 300 validators
+	maxVals := 100
+	maxPower := 1000
+	nTestCases := 5
+	for i := 0; i < nTestCases; i++ {
+		N := cmn.RandInt() % maxVals
+		vals := make([]*types.Validator, N)
+		totalVotePower := int64(0)
+		for j := 0; j < N; j++ {
+			votePower := int64(cmn.RandInt() % maxPower)
+			totalVotePower += votePower
+			privVal := types.NewMockPV()
+			pubKey := privVal.GetPubKey()
+			val := types.NewValidator(pubKey, votePower)
+			val.ProposerPriority = cmn.RandInt64()
+			vals[j] = val
+		}
+		valSet := types.NewValidatorSet(vals)
+		valSet.RescalePriorities(totalVotePower)
+		testProposerFreq(t, i, valSet)
+	}
+}
+
+// new val set with given powers and random initial priorities
+func genValSetWithPowers(powers []int64) *types.ValidatorSet {
+	size := len(powers)
+	vals := make([]*types.Validator, size)
+	totalVotePower := int64(0)
+	for i := 0; i < size; i++ {
+		totalVotePower += powers[i]
+		val := types.NewValidator(ed25519.GenPrivKey().PubKey(), powers[i])
+		val.ProposerPriority = cmn.RandInt64()
+		vals[i] = val
+	}
+	valSet := types.NewValidatorSet(vals)
+	valSet.RescalePriorities(totalVotePower)
+	return valSet
+}
+
+// test a proposer appears as frequently as expected
+func testProposerFreq(t *testing.T, caseNum int, valSet *types.ValidatorSet) {
+	N := valSet.Size()
+	totalPower := valSet.TotalVotingPower()
+
+	// run the proposer selection and track frequencies
+	runMult := 1
+	runs := int(totalPower) * runMult
+	freqs := make([]int, N)
+	for i := 0; i < runs; i++ {
+		prop := valSet.GetProposer()
+		idx, _ := valSet.GetByAddress(prop.Address)
+		freqs[idx] += 1
+		valSet.IncrementProposerPriority(1)
+	}
+
+	// assert frequencies match expected (max off by 1)
+	for i, freq := range freqs {
+		_, val := valSet.GetByIndex(i)
+		expectFreq := int(val.VotingPower) * runMult
+		gotFreq := freq
+		abs := int(math.Abs(float64(expectFreq - gotFreq)))
+
+		// max bound on expected vs seen freq was proven
+		// to be 1 for the 2 validator case in
+		// https://github.com/cwgoes/tm-proposer-idris
+		// and inferred to generalize to N-1
+		bound := N - 1
+		require.True(t, abs <= bound, fmt.Sprintf("Case %d val %d (%d): got %d, expected %d", caseNum, i, N, gotFreq, expectFreq))
+	}
+}
+
+// TestProposerPriorityDoesNotGetResetToZero assert that we preserve accum when calling updateState
+// see https://github.com/tendermint/tendermint/issues/2718
+func TestProposerPriorityDoesNotGetResetToZero(t *testing.T) {
+	tearDown, _, state := setupTestCase(t)
+	defer tearDown(t)
+	val1VotingPower := int64(10)
+	val1PubKey := ed25519.GenPrivKey().PubKey()
+	val1 := &types.Validator{Address: val1PubKey.Address(), PubKey: val1PubKey, VotingPower: val1VotingPower}
+
+	state.Validators = types.NewValidatorSet([]*types.Validator{val1})
+	state.NextValidators = state.Validators
+
+	// NewValidatorSet calls IncrementProposerPriority but uses on a copy of val1
+	assert.EqualValues(t, 0, val1.ProposerPriority)
+
+	block := makeBlock(state, state.LastBlockHeight+1)
+	blockID := types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+	abciResponses := &ABCIResponses{
+		EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: nil},
+	}
+	validatorUpdates, err := types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+	require.NoError(t, err)
+	updatedState, err := updateState(state, blockID, &block.Header, abciResponses, validatorUpdates)
+	assert.NoError(t, err)
+	curTotal := val1VotingPower
+	// one increment step and one validator: 0 + power - total_power == 0
+	assert.Equal(t, 0+val1VotingPower-curTotal, updatedState.NextValidators.Validators[0].ProposerPriority)
+
+	// add a validator
+	val2PubKey := ed25519.GenPrivKey().PubKey()
+	val2VotingPower := int64(100)
+	updateAddVal := abci.ValidatorUpdate{PubKey: types.TM2PB.PubKey(val2PubKey), Power: val2VotingPower}
+	validatorUpdates, err = types.PB2TM.ValidatorUpdates([]abci.ValidatorUpdate{updateAddVal})
+	assert.NoError(t, err)
+	updatedState2, err := updateState(updatedState, blockID, &block.Header, abciResponses, validatorUpdates)
+	assert.NoError(t, err)
+
+	require.Equal(t, len(updatedState2.NextValidators.Validators), 2)
+	_, updatedVal1 := updatedState2.NextValidators.GetByAddress(val1PubKey.Address())
+	_, addedVal2 := updatedState2.NextValidators.GetByAddress(val2PubKey.Address())
+	// adding a validator should not lead to a ProposerPriority equal to zero (unless the combination of averaging and
+	// incrementing would cause so; which is not the case here)
+	totalPowerBefore2 := curTotal
+	// while adding we compute prio == -1.125 * total:
+	wantVal2ProposerPrio := -(totalPowerBefore2 + (totalPowerBefore2 >> 3))
+	wantVal2ProposerPrio = wantVal2ProposerPrio + val2VotingPower
+	// then increment:
+	totalPowerAfter := val1VotingPower + val2VotingPower
+	// mostest:
+	wantVal2ProposerPrio = wantVal2ProposerPrio - totalPowerAfter
+	avg := big.NewInt(0).Add(big.NewInt(val1VotingPower), big.NewInt(wantVal2ProposerPrio))
+	avg.Div(avg, big.NewInt(2))
+	wantVal2ProposerPrio = wantVal2ProposerPrio - avg.Int64()
+	wantVal1Prio := 0 + val1VotingPower - avg.Int64()
+	assert.Equal(t, wantVal1Prio, updatedVal1.ProposerPriority)
+	assert.Equal(t, wantVal2ProposerPrio, addedVal2.ProposerPriority)
+
+	// Updating a validator does not reset the ProposerPriority to zero:
+	updatedVotingPowVal2 := int64(1)
+	updateVal := abci.ValidatorUpdate{PubKey: types.TM2PB.PubKey(val2PubKey), Power: updatedVotingPowVal2}
+	validatorUpdates, err = types.PB2TM.ValidatorUpdates([]abci.ValidatorUpdate{updateVal})
+	assert.NoError(t, err)
+
+	// this will cause the diff of priorities (31)
+	// to be larger than threshold == 2*totalVotingPower (22):
+	updatedState3, err := updateState(updatedState2, blockID, &block.Header, abciResponses, validatorUpdates)
+	assert.NoError(t, err)
+
+	require.Equal(t, len(updatedState3.NextValidators.Validators), 2)
+	_, prevVal1 := updatedState3.Validators.GetByAddress(val1PubKey.Address())
+	_, updatedVal2 := updatedState3.NextValidators.GetByAddress(val2PubKey.Address())
+
+	// divide previous priorities by 2 == CEIL(31/22) as diff > threshold:
+	expectedVal1PrioBeforeAvg := prevVal1.ProposerPriority/2 + prevVal1.VotingPower
+	wantVal2ProposerPrio = wantVal2ProposerPrio/2 + updatedVotingPowVal2
+	// val1 will be proposer:
+	total := val1VotingPower + updatedVotingPowVal2
+	expectedVal1PrioBeforeAvg = expectedVal1PrioBeforeAvg - total
+	avgI64 := (wantVal2ProposerPrio + expectedVal1PrioBeforeAvg) / 2
+	wantVal2ProposerPrio = wantVal2ProposerPrio - avgI64
+	wantVal1Prio = expectedVal1PrioBeforeAvg - avgI64
+	assert.Equal(t, wantVal2ProposerPrio, updatedVal2.ProposerPriority)
+	_, updatedVal1 = updatedState3.NextValidators.GetByAddress(val1PubKey.Address())
+	assert.Equal(t, wantVal1Prio, updatedVal1.ProposerPriority)
+}
+
+func TestProposerPriorityProposerAlternates(t *testing.T) {
+	// Regression test that would fail if the inner workings of
+	// IncrementProposerPriority change.
+	// Additionally, make sure that same power validators alternate if both
+	// have the same voting power (and the 2nd was added later).
+	tearDown, _, state := setupTestCase(t)
+	defer tearDown(t)
+	val1VotingPower := int64(10)
+	val1PubKey := ed25519.GenPrivKey().PubKey()
+	val1 := &types.Validator{Address: val1PubKey.Address(), PubKey: val1PubKey, VotingPower: val1VotingPower}
+
+	// reset state validators to above validator
+	state.Validators = types.NewValidatorSet([]*types.Validator{val1})
+	state.NextValidators = state.Validators
+	// we only have one validator:
+	assert.Equal(t, val1PubKey.Address(), state.Validators.Proposer.Address)
+
+	block := makeBlock(state, state.LastBlockHeight+1)
+	blockID := types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+	// no updates:
+	abciResponses := &ABCIResponses{
+		EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: nil},
+	}
+	validatorUpdates, err := types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+	require.NoError(t, err)
+
+	updatedState, err := updateState(state, blockID, &block.Header, abciResponses, validatorUpdates)
+	assert.NoError(t, err)
+
+	// 0 + 10 (initial prio) - 10 (avg) - 10 (mostest - total) = -10
+	totalPower := val1VotingPower
+	wantVal1Prio := 0 + val1VotingPower - totalPower
+	assert.Equal(t, wantVal1Prio, updatedState.NextValidators.Validators[0].ProposerPriority)
+	assert.Equal(t, val1PubKey.Address(), updatedState.NextValidators.Proposer.Address)
+
+	// add a validator with the same voting power as the first
+	val2PubKey := ed25519.GenPrivKey().PubKey()
+	updateAddVal := abci.ValidatorUpdate{PubKey: types.TM2PB.PubKey(val2PubKey), Power: val1VotingPower}
+	validatorUpdates, err = types.PB2TM.ValidatorUpdates([]abci.ValidatorUpdate{updateAddVal})
+	assert.NoError(t, err)
+
+	updatedState2, err := updateState(updatedState, blockID, &block.Header, abciResponses, validatorUpdates)
+	assert.NoError(t, err)
+
+	require.Equal(t, len(updatedState2.NextValidators.Validators), 2)
+	assert.Equal(t, updatedState2.Validators, updatedState.NextValidators)
+
+	// val1 will still be proposer as val2 just got added:
+	assert.Equal(t, val1PubKey.Address(), updatedState.NextValidators.Proposer.Address)
+	assert.Equal(t, updatedState2.Validators.Proposer.Address, updatedState2.NextValidators.Proposer.Address)
+	assert.Equal(t, updatedState2.Validators.Proposer.Address, val1PubKey.Address())
+	assert.Equal(t, updatedState2.NextValidators.Proposer.Address, val1PubKey.Address())
+
+	_, updatedVal1 := updatedState2.NextValidators.GetByAddress(val1PubKey.Address())
+	_, oldVal1 := updatedState2.Validators.GetByAddress(val1PubKey.Address())
+	_, updatedVal2 := updatedState2.NextValidators.GetByAddress(val2PubKey.Address())
+
+	totalPower = val1VotingPower // no update
+	v2PrioWhenAddedVal2 := -(totalPower + (totalPower >> 3))
+	v2PrioWhenAddedVal2 = v2PrioWhenAddedVal2 + val1VotingPower       // -11 + 10 == -1
+	v1PrioWhenAddedVal2 := oldVal1.ProposerPriority + val1VotingPower // -10 + 10 == 0
+	totalPower = 2 * val1VotingPower                                  // now we have to validators with that power
+	v1PrioWhenAddedVal2 = v1PrioWhenAddedVal2 - totalPower            // mostest
+	// have to express the AVG in big.Ints as -1/2 == -1 in big.Int while -1/2 == 0 in int64
+	avgSum := big.NewInt(0).Add(big.NewInt(v2PrioWhenAddedVal2), big.NewInt(v1PrioWhenAddedVal2))
+	avg := avgSum.Div(avgSum, big.NewInt(2))
+	expectedVal2Prio := v2PrioWhenAddedVal2 - avg.Int64()
+	totalPower = 2 * val1VotingPower // 10 + 10
+	expectedVal1Prio := oldVal1.ProposerPriority + val1VotingPower - avg.Int64() - totalPower
+	// val1's ProposerPriority story: -10 (see above) + 10 (voting pow) - (-1) (avg) - 20 (total) == -19
+	assert.EqualValues(t, expectedVal1Prio, updatedVal1.ProposerPriority)
+	// val2 prio when added: -(totalVotingPower + (totalVotingPower >> 3)) == -11
+	// -> -11 + 10  (voting power) - (-1) (avg) == 0
+	assert.EqualValues(t, expectedVal2Prio, updatedVal2.ProposerPriority, "unexpected proposer priority for validator: %v", updatedVal2)
+
+	validatorUpdates, err = types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+	require.NoError(t, err)
+
+	updatedState3, err := updateState(updatedState2, blockID, &block.Header, abciResponses, validatorUpdates)
+	assert.NoError(t, err)
+
+	// proposer changes from now on (every iteration) as long as there are no changes in the validator set:
+	assert.NotEqual(t, updatedState3.Validators.Proposer.Address, updatedState3.NextValidators.Proposer.Address)
+
+	assert.Equal(t, updatedState3.Validators, updatedState2.NextValidators)
+	_, updatedVal1 = updatedState3.NextValidators.GetByAddress(val1PubKey.Address())
+	_, oldVal1 = updatedState3.Validators.GetByAddress(val1PubKey.Address())
+	_, updatedVal2 = updatedState3.NextValidators.GetByAddress(val2PubKey.Address())
+	_, oldVal2 := updatedState3.Validators.GetByAddress(val2PubKey.Address())
+
+	// val2 will be proposer:
+	assert.Equal(t, val2PubKey.Address(), updatedState3.NextValidators.Proposer.Address)
+	// check if expected proposer prio is matched:
+
+	expectedVal1Prio2 := oldVal1.ProposerPriority + val1VotingPower
+	expectedVal2Prio2 := oldVal2.ProposerPriority + val1VotingPower - totalPower
+	avgSum = big.NewInt(expectedVal1Prio + expectedVal2Prio)
+	avg = avgSum.Div(avgSum, big.NewInt(2))
+	expectedVal1Prio -= avg.Int64()
+	expectedVal2Prio -= avg.Int64()
+
+	// -19 + 10 - 0 (avg) == -9
+	assert.EqualValues(t, expectedVal1Prio2, updatedVal1.ProposerPriority, "unexpected proposer priority for validator: %v", updatedVal2)
+	// 0 + 10 - 0 (avg) - 20 (total) == -10
+	assert.EqualValues(t, expectedVal2Prio2, updatedVal2.ProposerPriority, "unexpected proposer priority for validator: %v", updatedVal2)
+
+	// no changes in voting power and both validators have same voting power
+	// -> proposers should alternate:
+	oldState := updatedState3
+	for i := 0; i < 1000; i++ {
+		// no validator updates:
+		abciResponses := &ABCIResponses{
+			EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: nil},
+		}
+		validatorUpdates, err = types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+		require.NoError(t, err)
+
+		updatedState, err := updateState(oldState, blockID, &block.Header, abciResponses, validatorUpdates)
+		assert.NoError(t, err)
+		// alternate (and cyclic priorities):
+		assert.NotEqual(t, updatedState.Validators.Proposer.Address, updatedState.NextValidators.Proposer.Address, "iter: %v", i)
+		assert.Equal(t, oldState.Validators.Proposer.Address, updatedState.NextValidators.Proposer.Address, "iter: %v", i)
+
+		_, updatedVal1 = updatedState.NextValidators.GetByAddress(val1PubKey.Address())
+		_, updatedVal2 = updatedState.NextValidators.GetByAddress(val2PubKey.Address())
+
+		if i%2 == 0 {
+			assert.Equal(t, updatedState.Validators.Proposer.Address, val2PubKey.Address())
+			assert.Equal(t, expectedVal1Prio, updatedVal1.ProposerPriority) // -19
+			assert.Equal(t, expectedVal2Prio, updatedVal2.ProposerPriority) // 0
+		} else {
+			assert.Equal(t, updatedState.Validators.Proposer.Address, val1PubKey.Address())
+			assert.Equal(t, expectedVal1Prio2, updatedVal1.ProposerPriority) // -9
+			assert.Equal(t, expectedVal2Prio2, updatedVal2.ProposerPriority) // -10
+		}
+		// update for next iteration:
+		oldState = updatedState
+	}
+}
+
+func TestLargeGenesisValidator(t *testing.T) {
+	tearDown, _, state := setupTestCase(t)
+	defer tearDown(t)
+
+	genesisVotingPower := int64(types.MaxTotalVotingPower / 1000)
+	genesisPubKey := ed25519.GenPrivKey().PubKey()
+	// fmt.Println("genesis addr: ", genesisPubKey.Address())
+	genesisVal := &types.Validator{Address: genesisPubKey.Address(), PubKey: genesisPubKey, VotingPower: genesisVotingPower}
+	// reset state validators to above validator
+	state.Validators = types.NewValidatorSet([]*types.Validator{genesisVal})
+	state.NextValidators = state.Validators
+	require.True(t, len(state.Validators.Validators) == 1)
+
+	// update state a few times with no validator updates
+	// asserts that the single validator's ProposerPrio stays the same
+	oldState := state
+	for i := 0; i < 10; i++ {
+		// no updates:
+		abciResponses := &ABCIResponses{
+			EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: nil},
+		}
+		validatorUpdates, err := types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+		require.NoError(t, err)
+
+		block := makeBlock(oldState, oldState.LastBlockHeight+1)
+		blockID := types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+
+		updatedState, err := updateState(oldState, blockID, &block.Header, abciResponses, validatorUpdates)
+		// no changes in voting power (ProposerPrio += VotingPower == Voting in 1st round; than shiftByAvg == 0,
+		// than -Total == -Voting)
+		// -> no change in ProposerPrio (stays zero):
+		assert.EqualValues(t, oldState.NextValidators, updatedState.NextValidators)
+		assert.EqualValues(t, 0, updatedState.NextValidators.Proposer.ProposerPriority)
+
+		oldState = updatedState
+	}
+	// add another validator, do a few iterations (create blocks),
+	// add more validators with same voting power as the 2nd
+	// let the genesis validator "unbond",
+	// see how long it takes until the effect wears off and both begin to alternate
+	// see: https://github.com/tendermint/tendermint/issues/2960
+	firstAddedValPubKey := ed25519.GenPrivKey().PubKey()
+	firstAddedValVotingPower := int64(10)
+	firstAddedVal := abci.ValidatorUpdate{PubKey: types.TM2PB.PubKey(firstAddedValPubKey), Power: firstAddedValVotingPower}
+	validatorUpdates, err := types.PB2TM.ValidatorUpdates([]abci.ValidatorUpdate{firstAddedVal})
+	assert.NoError(t, err)
+	abciResponses := &ABCIResponses{
+		EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: []abci.ValidatorUpdate{firstAddedVal}},
+	}
+	block := makeBlock(oldState, oldState.LastBlockHeight+1)
+	blockID := types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+	updatedState, err := updateState(oldState, blockID, &block.Header, abciResponses, validatorUpdates)
+
+	lastState := updatedState
+	for i := 0; i < 200; i++ {
+		// no updates:
+		abciResponses := &ABCIResponses{
+			EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: nil},
+		}
+		validatorUpdates, err := types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+		require.NoError(t, err)
+
+		block := makeBlock(lastState, lastState.LastBlockHeight+1)
+		blockID := types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+
+		updatedStateInner, err := updateState(lastState, blockID, &block.Header, abciResponses, validatorUpdates)
+		lastState = updatedStateInner
+	}
+	// set state to last state of above iteration
+	state = lastState
+
+	// set oldState to state before above iteration
+	oldState = updatedState
+	_, oldGenesisVal := oldState.NextValidators.GetByAddress(genesisVal.Address)
+	_, newGenesisVal := state.NextValidators.GetByAddress(genesisVal.Address)
+	_, addedOldVal := oldState.NextValidators.GetByAddress(firstAddedValPubKey.Address())
+	_, addedNewVal := state.NextValidators.GetByAddress(firstAddedValPubKey.Address())
+	// expect large negative proposer priority for both (genesis validator decreased, 2nd validator increased):
+	assert.True(t, oldGenesisVal.ProposerPriority > newGenesisVal.ProposerPriority)
+	assert.True(t, addedOldVal.ProposerPriority < addedNewVal.ProposerPriority)
+
+	// add 10 validators with the same voting power as the one added directly after genesis:
+	for i := 0; i < 10; i++ {
+		addedPubKey := ed25519.GenPrivKey().PubKey()
+
+		addedVal := abci.ValidatorUpdate{PubKey: types.TM2PB.PubKey(addedPubKey), Power: firstAddedValVotingPower}
+		validatorUpdates, err := types.PB2TM.ValidatorUpdates([]abci.ValidatorUpdate{addedVal})
+		assert.NoError(t, err)
+
+		abciResponses := &ABCIResponses{
+			EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: []abci.ValidatorUpdate{addedVal}},
+		}
+		block := makeBlock(oldState, oldState.LastBlockHeight+1)
+		blockID := types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+		state, err = updateState(state, blockID, &block.Header, abciResponses, validatorUpdates)
+	}
+	require.Equal(t, 10+2, len(state.NextValidators.Validators))
+
+	// remove genesis validator:
+	removeGenesisVal := abci.ValidatorUpdate{PubKey: types.TM2PB.PubKey(genesisPubKey), Power: 0}
+	abciResponses = &ABCIResponses{
+		EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: []abci.ValidatorUpdate{removeGenesisVal}},
+	}
+	block = makeBlock(oldState, oldState.LastBlockHeight+1)
+	blockID = types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+	validatorUpdates, err = types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+	require.NoError(t, err)
+	updatedState, err = updateState(state, blockID, &block.Header, abciResponses, validatorUpdates)
+	require.NoError(t, err)
+	// only the first added val (not the genesis val) should be left
+	assert.Equal(t, 11, len(updatedState.NextValidators.Validators))
+
+	// call update state until the effect for the 3rd added validator
+	// being proposer for a long time after the genesis validator left wears off:
+	curState := updatedState
+	count := 0
+	isProposerUnchanged := true
+	for isProposerUnchanged {
+		abciResponses := &ABCIResponses{
+			EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: nil},
+		}
+		validatorUpdates, err = types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+		require.NoError(t, err)
+		block = makeBlock(curState, curState.LastBlockHeight+1)
+		blockID = types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+		curState, err = updateState(curState, blockID, &block.Header, abciResponses, validatorUpdates)
+		if !bytes.Equal(curState.Validators.Proposer.Address, curState.NextValidators.Proposer.Address) {
+			isProposerUnchanged = false
+		}
+		count++
+	}
+	updatedState = curState
+	// the proposer changes after this number of blocks
+	firstProposerChangeExpectedAfter := 1
+	assert.Equal(t, firstProposerChangeExpectedAfter, count)
+	// store proposers here to see if we see them again in the same order:
+	numVals := len(updatedState.Validators.Validators)
+	proposers := make([]*types.Validator, numVals)
+	for i := 0; i < 100; i++ {
+		// no updates:
+		abciResponses := &ABCIResponses{
+			EndBlock: &abci.ResponseEndBlock{ValidatorUpdates: nil},
+		}
+		validatorUpdates, err := types.PB2TM.ValidatorUpdates(abciResponses.EndBlock.ValidatorUpdates)
+		require.NoError(t, err)
+
+		block := makeBlock(updatedState, updatedState.LastBlockHeight+1)
+		blockID := types.BlockID{block.Hash(), block.MakePartSet(testPartSize).Header()}
+
+		updatedState, err = updateState(updatedState, blockID, &block.Header, abciResponses, validatorUpdates)
+		if i > numVals { // expect proposers to cycle through after the first iteration (of numVals blocks):
+			if proposers[i%numVals] == nil {
+				proposers[i%numVals] = updatedState.NextValidators.Proposer
+			} else {
+				assert.Equal(t, proposers[i%numVals], updatedState.NextValidators.Proposer)
+			}
+		}
+	}
+}
+
 func TestStoreLoadValidatorsIncrementsProposerPriority(t *testing.T) {
 	const valSetSize = 2
 	tearDown, stateDB, state := setupTestCase(t)

types/block.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/tendermint/tendermint/crypto"
 	"github.com/tendermint/tendermint/crypto/merkle"
+	"github.com/tendermint/tendermint/crypto/tmhash"
 	cmn "github.com/tendermint/tendermint/libs/common"
 	"github.com/tendermint/tendermint/version"
 )
@@ -637,6 +638,7 @@ func (commit *Commit) StringIndented(indent string) string {
 //-----------------------------------------------------------------------------
 
 // SignedHeader is a header along with the commits that prove it.
+// It is the basis of the lite client.
 type SignedHeader struct {
 	*Header `json:"header"`
 	Commit  *Commit `json:"commit"`
@@ -789,11 +791,6 @@ type BlockID struct {
 	PartsHeader PartSetHeader `json:"parts"`
 }
 
-// IsZero returns true if this is the BlockID for a nil-block
-func (blockID BlockID) IsZero() bool {
-	return len(blockID.Hash) == 0 && blockID.PartsHeader.IsZero()
-}
-
 // Equals returns true if the BlockID matches the given BlockID
 func (blockID BlockID) Equals(other BlockID) bool {
 	return bytes.Equal(blockID.Hash, other.Hash) &&
@@ -821,6 +818,19 @@ func (blockID BlockID) ValidateBasic() error {
 	return nil
 }
 
+// IsZero returns true if this is the BlockID of a nil block.
+func (blockID BlockID) IsZero() bool {
+	return len(blockID.Hash) == 0 &&
+		blockID.PartsHeader.IsZero()
+}
+
+// IsComplete returns true if this is a valid BlockID of a non-nil block.
+func (blockID BlockID) IsComplete() bool {
+	return len(blockID.Hash) == tmhash.Size &&
+		blockID.PartsHeader.Total > 0 &&
+		len(blockID.PartsHeader.Hash) == tmhash.Size
+}
+
 // String returns a human readable string representation of the BlockID
 func (blockID BlockID) String() string {
 	return fmt.Sprintf(`%v:%v`, blockID.Hash, blockID.PartsHeader)

types/canonical.go

@@ -36,8 +36,8 @@ type CanonicalVote struct {
 	Type      SignedMsgType // type alias for byte
 	Height    int64         `binary:"fixed64"`
 	Round     int64         `binary:"fixed64"`
-	Timestamp time.Time
 	BlockID   CanonicalBlockID
+	Timestamp time.Time
 	ChainID   string
 }
 
@@ -75,8 +75,8 @@ func CanonicalizeVote(chainID string, vote *Vote) CanonicalVote {
 		Type:      vote.Type,
 		Height:    vote.Height,
 		Round:     int64(vote.Round), // cast int->int64 to make amino encode it fixed64 (does not work for int)
-		Timestamp: vote.Timestamp,
 		BlockID:   CanonicalizeBlockID(vote.BlockID),
+		Timestamp: vote.Timestamp,
 		ChainID:   chainID,
 	}
 }

types/params.go

@@ -22,6 +22,14 @@ type ConsensusParams struct {
 	Validator ValidatorParams `json:"validator"`
 }
 
+// HashedParams is a subset of ConsensusParams.
+// It is amino encoded and hashed into
+// the Header.ConsensusHash.
+type HashedParams struct {
+	BlockMaxBytes int64
+	BlockMaxGas   int64
+}
+
 // BlockSizeParams define limits on the block size.
 type BlockSizeParams struct {
 	MaxBytes int64 `json:"max_bytes"`
@@ -116,13 +124,16 @@ func (params *ConsensusParams) Validate() error {
 	return nil
 }
 
-// Hash returns a hash of the parameters to store in the block header
-// No Merkle tree here, only three values are hashed here
-// thus benefit from saving space < drawbacks from proofs' overhead
-// Revisit this function if new fields are added to ConsensusParams
+// Hash returns a hash of a subset of the parameters to store in the block header.
+// Only the Block.MaxBytes and Block.MaxGas are included in the hash.
+// This allows the ConsensusParams to evolve more without breaking the block
+// protocol. No need for a Merkle tree here, just a small struct to hash.
 func (params *ConsensusParams) Hash() []byte {
 	hasher := tmhash.New()
-	bz := cdcEncode(params)
+	bz := cdcEncode(HashedParams{
+		params.BlockSize.MaxBytes,
+		params.BlockSize.MaxGas,
+	})
 	if bz == nil {
 		panic("cannot fail to encode ConsensusParams")
 	}

types/part_set.go

@@ -9,7 +9,6 @@ import (
 	"github.com/pkg/errors"
 
 	"github.com/tendermint/tendermint/crypto/merkle"
-	"github.com/tendermint/tendermint/crypto/tmhash"
 	cmn "github.com/tendermint/tendermint/libs/common"
 )
 
@@ -27,16 +26,6 @@ type Part struct {
 	hash []byte
 }
 
-func (part *Part) Hash() []byte {
-	if part.hash != nil {
-		return part.hash
-	}
-	hasher := tmhash.New()
-	hasher.Write(part.Bytes) // nolint: errcheck, gas
-	part.hash = hasher.Sum(nil)
-	return part.hash
-}
-
 // ValidateBasic performs basic validation.
 func (part *Part) ValidateBasic() error {
 	if part.Index < 0 {
@@ -75,7 +64,7 @@ func (psh PartSetHeader) String() string {
 }
 
 func (psh PartSetHeader) IsZero() bool {
-	return psh.Total == 0
+	return psh.Total == 0 && len(psh.Hash) == 0
 }
 
 func (psh PartSetHeader) Equals(other PartSetHeader) bool {
@@ -217,7 +206,7 @@ func (ps *PartSet) AddPart(part *Part) (bool, error) {
 	}
 
 	// Check hash proof
-	if part.Proof.Verify(ps.Hash(), part.Hash()) != nil {
+	if part.Proof.Verify(ps.Hash(), part.Bytes) != nil {
 		return false, ErrPartSetInvalidProof
 	}
 

types/proposal.go

@@ -60,6 +60,10 @@ func (p *Proposal) ValidateBasic() error {
 	if err := p.BlockID.ValidateBasic(); err != nil {
 		return fmt.Errorf("Wrong BlockID: %v", err)
 	}
+	// ValidateBasic above would pass even if the BlockID was empty:
+	if !p.BlockID.IsComplete() {
+		return fmt.Errorf("Expected a complete, non-empty BlockID, got: %v", p.BlockID)
+	}
 
 	// NOTE: Timestamp validation is subtle and handled elsewhere.
 

types/results.go

@@ -3,25 +3,20 @@ package types
 import (
 	abci "github.com/tendermint/tendermint/abci/types"
 	"github.com/tendermint/tendermint/crypto/merkle"
-	"github.com/tendermint/tendermint/crypto/tmhash"
 	cmn "github.com/tendermint/tendermint/libs/common"
 )
 
 //-----------------------------------------------------------------------------
 
 // ABCIResult is the deterministic component of a ResponseDeliverTx.
-// TODO: add Tags
+// TODO: add tags and other fields
+// https://github.com/tendermint/tendermint/issues/1007
 type ABCIResult struct {
 	Code uint32       `json:"code"`
 	Data cmn.HexBytes `json:"data"`
 }
 
-// Hash returns the canonical hash of the ABCIResult
-func (a ABCIResult) Hash() []byte {
-	bz := tmhash.Sum(cdcEncode(a))
-	return bz
-}
-
+// Bytes returns the amino encoded ABCIResult
 func (a ABCIResult) Bytes() []byte {
 	return cdcEncode(a)
 }

types/results_test.go

@@ -16,20 +16,21 @@ func TestABCIResults(t *testing.T) {
 	e := ABCIResult{Code: 14, Data: []byte("foo")}
 	f := ABCIResult{Code: 14, Data: []byte("bar")}
 
-	// Nil and []byte{} should produce the same hash.
-	require.Equal(t, a.Hash(), a.Hash())
-	require.Equal(t, b.Hash(), b.Hash())
-	require.Equal(t, a.Hash(), b.Hash())
+	// Nil and []byte{} should produce the same bytes
+	require.Equal(t, a.Bytes(), a.Bytes())
+	require.Equal(t, b.Bytes(), b.Bytes())
+	require.Equal(t, a.Bytes(), b.Bytes())
 
 	// a and b should be the same, don't go in results.
 	results := ABCIResults{a, c, d, e, f}
 
-	// Make sure each result hashes properly.
+	// Make sure each result serializes differently
 	var last []byte
-	for i, res := range results {
-		h := res.Hash()
-		assert.NotEqual(t, last, h, "%d", i)
-		last = h
+	assert.Equal(t, last, a.Bytes()) // first one is empty
+	for i, res := range results[1:] {
+		bz := res.Bytes()
+		assert.NotEqual(t, last, bz, "%d", i)
+		last = bz
 	}
 
 	// Make sure that we can get a root hash from results and verify proofs.
@@ -38,7 +39,7 @@ func TestABCIResults(t *testing.T) {
 
 	for i, res := range results {
 		proof := results.ProveResult(i)
-		valid := proof.Verify(root, res.Hash())
+		valid := proof.Verify(root, res.Bytes())
 		assert.NoError(t, valid, "%d", i)
 	}
 }

types/tx.go

@@ -31,13 +31,14 @@ func (tx Tx) String() string {
 // Txs is a slice of Tx.
 type Txs []Tx
 
-// Hash returns the simple Merkle root hash of the transactions.
+// Hash returns the Merkle root hash of the transaction hashes.
+// i.e. the leaves of the tree are the hashes of the txs.
 func (txs Txs) Hash() []byte {
 	// These allocations will be removed once Txs is switched to [][]byte,
 	// ref #2603. This is because golang does not allow type casting slices without unsafe
 	txBzs := make([][]byte, len(txs))
 	for i := 0; i < len(txs); i++ {
-		txBzs[i] = txs[i]
+		txBzs[i] = txs[i].Hash()
 	}
 	return merkle.SimpleHashFromByteSlices(txBzs)
 }
@@ -69,7 +70,7 @@ func (txs Txs) Proof(i int) TxProof {
 	l := len(txs)
 	bzs := make([][]byte, l)
 	for i := 0; i < l; i++ {
-		bzs[i] = txs[i]
+		bzs[i] = txs[i].Hash()
 	}
 	root, proofs := merkle.SimpleProofsFromByteSlices(bzs)
 
@@ -87,8 +88,8 @@ type TxProof struct {
 	Proof    merkle.SimpleProof
 }
 
-// LeadHash returns the hash of the this proof refers to.
-func (tp TxProof) LeafHash() []byte {
+// Leaf returns the hash(tx), which is the leaf in the merkle tree which this proof refers to.
+func (tp TxProof) Leaf() []byte {
 	return tp.Data.Hash()
 }
 
@@ -104,7 +105,7 @@ func (tp TxProof) Validate(dataHash []byte) error {
 	if tp.Proof.Total <= 0 {
 		return errors.New("Proof total must be positive")
 	}
-	valid := tp.Proof.Verify(tp.RootHash, tp.LeafHash())
+	valid := tp.Proof.Verify(tp.RootHash, tp.Leaf())
 	if valid != nil {
 		return errors.New("Proof is not internally consistent")
 	}

types/tx_test.go

@@ -66,14 +66,13 @@ func TestValidTxProof(t *testing.T) {
 		root := txs.Hash()
 		// make sure valid proof for every tx
 		for i := range txs {
-			leaf := txs[i]
-			leafHash := leaf.Hash()
+			tx := []byte(txs[i])
 			proof := txs.Proof(i)
 			assert.Equal(t, i, proof.Proof.Index, "%d: %d", h, i)
 			assert.Equal(t, len(txs), proof.Proof.Total, "%d: %d", h, i)
 			assert.EqualValues(t, root, proof.RootHash, "%d: %d", h, i)
-			assert.EqualValues(t, leaf, proof.Data, "%d: %d", h, i)
-			assert.EqualValues(t, leafHash, proof.LeafHash(), "%d: %d", h, i)
+			assert.EqualValues(t, tx, proof.Data, "%d: %d", h, i)
+			assert.EqualValues(t, txs[i].Hash(), proof.Leaf(), "%d: %d", h, i)
 			assert.Nil(t, proof.Validate(root), "%d: %d", h, i)
 			assert.NotNil(t, proof.Validate([]byte("foobar")), "%d: %d", h, i)
 

types/validator.go

@@ -4,8 +4,6 @@ import (
 	"bytes"
 	"fmt"
 
-	"github.com/tendermint/tendermint/crypto/tmhash"
-
 	"github.com/tendermint/tendermint/crypto"
 	cmn "github.com/tendermint/tendermint/libs/common"
 )
@@ -70,12 +68,6 @@ func (v *Validator) String() string {
 		v.ProposerPriority)
 }
 
-// Hash computes the unique ID of a validator with a given voting power.
-// It excludes the ProposerPriority value, which changes with every round.
-func (v *Validator) Hash() []byte {
-	return tmhash.Sum(v.Bytes())
-}
-
 // Bytes computes the unique encoding of a validator with a given voting power.
 // These are the bytes that gets hashed in consensus. It excludes address
 // as its redundant with the pubkey. This also excludes ProposerPriority

types/validator_set.go

@@ -13,13 +13,13 @@ import (
 )
 
 // The maximum allowed total voting power.
-// We set the ProposerPriority of freshly added validators to -1.125*totalVotingPower.
-// To compute 1.125*totalVotingPower efficiently, we do:
-// totalVotingPower + (totalVotingPower >> 3) because
-// x + (x >> 3) = x + x/8 = x * (1 + 0.125).
-// MaxTotalVotingPower is the largest int64 `x` with the property that `x + (x >> 3)` is
-// still in the bounds of int64.
-const MaxTotalVotingPower = int64(8198552921648689607)
+// It needs to be sufficiently small to, in all cases::
+// 1. prevent clipping in incrementProposerPriority()
+// 2. let (diff+diffMax-1) not overflow in IncrementPropposerPriotity()
+// (Proof of 1 is tricky, left to the reader).
+// It could be higher, but this is sufficiently large for our purposes,
+// and leaves room for defensive purposes.
+const MaxTotalVotingPower = int64(math.MaxInt64) / 8
 
 // ValidatorSet represent a set of *Validator at a given height.
 // The validators can be fetched by address or index.
@@ -78,44 +78,57 @@ func (vals *ValidatorSet) IncrementProposerPriority(times int) {
 		panic("Cannot call IncrementProposerPriority with non-positive times")
 	}
 
-	const shiftEveryNthIter = 10
+	// Cap the difference between priorities to be proportional to 2*totalPower by
+	// re-normalizing priorities, i.e., rescale all priorities by multiplying with:
+	//  2*totalVotingPower/(maxPriority - minPriority)
+	diffMax := 2 * vals.TotalVotingPower()
+	vals.RescalePriorities(diffMax)
+
 	var proposer *Validator
 	// call IncrementProposerPriority(1) times times:
 	for i := 0; i < times; i++ {
-		shiftByAvgProposerPriority := i%shiftEveryNthIter == 0
-		proposer = vals.incrementProposerPriority(shiftByAvgProposerPriority)
-	}
-	isShiftedAvgOnLastIter := (times-1)%shiftEveryNthIter == 0
-	if !isShiftedAvgOnLastIter {
-		validatorsHeap := cmn.NewHeap()
-		vals.shiftByAvgProposerPriority(validatorsHeap)
+		proposer = vals.incrementProposerPriority()
 	}
+	vals.shiftByAvgProposerPriority()
+
 	vals.Proposer = proposer
 }
 
-func (vals *ValidatorSet) incrementProposerPriority(subAvg bool) *Validator {
-	for _, val := range vals.Validators {
-		// Check for overflow for sum.
-		val.ProposerPriority = safeAddClip(val.ProposerPriority, val.VotingPower)
+func (vals *ValidatorSet) RescalePriorities(diffMax int64) {
+	// NOTE: This check is merely a sanity check which could be
+	// removed if all tests would init. voting power appropriately;
+	// i.e. diffMax should always be > 0
+	if diffMax <= 0 {
+		return
 	}
 
-	validatorsHeap := cmn.NewHeap()
-	if subAvg { // shift by avg ProposerPriority
-		vals.shiftByAvgProposerPriority(validatorsHeap)
-	} else { // just update the heap
+	// Caculating ceil(diff/diffMax):
+	// Re-normalization is performed by dividing by an integer for simplicity.
+	// NOTE: This may make debugging priority issues easier as well.
+	diff := computeMaxMinPriorityDiff(vals)
+	ratio := (diff + diffMax - 1) / diffMax
+	if ratio > 1 {
 		for _, val := range vals.Validators {
-			validatorsHeap.PushComparable(val, proposerPriorityComparable{val})
+			val.ProposerPriority /= ratio
 		}
 	}
+}
 
+func (vals *ValidatorSet) incrementProposerPriority() *Validator {
+	for _, val := range vals.Validators {
+		// Check for overflow for sum.
+		newPrio := safeAddClip(val.ProposerPriority, val.VotingPower)
+		val.ProposerPriority = newPrio
+	}
 	// Decrement the validator with most ProposerPriority:
-	mostest := validatorsHeap.Peek().(*Validator)
+	mostest := vals.getValWithMostPriority()
 	// mind underflow
 	mostest.ProposerPriority = safeSubClip(mostest.ProposerPriority, vals.TotalVotingPower())
 
 	return mostest
 }
 
+// should not be called on an empty validator set
 func (vals *ValidatorSet) computeAvgProposerPriority() int64 {
 	n := int64(len(vals.Validators))
 	sum := big.NewInt(0)
@@ -131,11 +144,38 @@ func (vals *ValidatorSet) computeAvgProposerPriority() int64 {
 	panic(fmt.Sprintf("Cannot represent avg ProposerPriority as an int64 %v", avg))
 }
 
-func (vals *ValidatorSet) shiftByAvgProposerPriority(validatorsHeap *cmn.Heap) {
+// compute the difference between the max and min ProposerPriority of that set
+func computeMaxMinPriorityDiff(vals *ValidatorSet) int64 {
+	max := int64(math.MinInt64)
+	min := int64(math.MaxInt64)
+	for _, v := range vals.Validators {
+		if v.ProposerPriority < min {
+			min = v.ProposerPriority
+		}
+		if v.ProposerPriority > max {
+			max = v.ProposerPriority
+		}
+	}
+	diff := max - min
+	if diff < 0 {
+		return -1 * diff
+	} else {
+		return diff
+	}
+}
+
+func (vals *ValidatorSet) getValWithMostPriority() *Validator {
+	var res *Validator
+	for _, val := range vals.Validators {
+		res = res.CompareProposerPriority(val)
+	}
+	return res
+}
+
+func (vals *ValidatorSet) shiftByAvgProposerPriority() {
 	avgProposerPriority := vals.computeAvgProposerPriority()
 	for _, val := range vals.Validators {
 		val.ProposerPriority = safeSubClip(val.ProposerPriority, avgProposerPriority)
-		validatorsHeap.PushComparable(val, proposerPriorityComparable{val})
 	}
 }
 
@@ -373,8 +413,7 @@ func (vals *ValidatorSet) VerifyCommit(chainID string, blockID BlockID, height i
 	if talliedVotingPower > vals.TotalVotingPower()*2/3 {
 		return nil
 	}
-	return fmt.Errorf("Invalid commit -- insufficient voting power: got %v, needed %v",
-		talliedVotingPower, vals.TotalVotingPower()*2/3+1)
+	return errTooMuchChange{talliedVotingPower, vals.TotalVotingPower()*2/3 + 1}
 }
 
 // VerifyFutureCommit will check to see if the set would be valid with a different
@@ -456,12 +495,37 @@ func (vals *ValidatorSet) VerifyFutureCommit(newSet *ValidatorSet, chainID strin
 	}
 
 	if oldVotingPower <= oldVals.TotalVotingPower()*2/3 {
-		return cmn.NewError("Invalid commit -- insufficient old voting power: got %v, needed %v",
-			oldVotingPower, oldVals.TotalVotingPower()*2/3+1)
+		return errTooMuchChange{oldVotingPower, oldVals.TotalVotingPower()*2/3 + 1}
 	}
 	return nil
 }
 
+//-----------------
+// ErrTooMuchChange
+
+func IsErrTooMuchChange(err error) bool {
+	switch err_ := err.(type) {
+	case cmn.Error:
+		_, ok := err_.Data().(errTooMuchChange)
+		return ok
+	case errTooMuchChange:
+		return true
+	default:
+		return false
+	}
+}
+
+type errTooMuchChange struct {
+	got    int64
+	needed int64
+}
+
+func (e errTooMuchChange) Error() string {
+	return fmt.Sprintf("Invalid commit -- insufficient old voting power: got %v, needed %v", e.got, e.needed)
+}
+
+//----------------
+
 func (vals *ValidatorSet) String() string {
 	return vals.StringIndented("")
 }
@@ -508,20 +572,6 @@ func (valz ValidatorsByAddress) Swap(i, j int) {
 	valz[j] = it
 }
 
-//-------------------------------------
-// Use with Heap for sorting validators by ProposerPriority
-
-type proposerPriorityComparable struct {
-	*Validator
-}
-
-// We want to find the validator with the greatest ProposerPriority.
-func (ac proposerPriorityComparable) Less(o interface{}) bool {
-	other := o.(proposerPriorityComparable).Validator
-	larger := ac.CompareProposerPriority(other)
-	return bytes.Equal(larger.Address, ac.Address)
-}
-
 //----------------------------------------
 // For testing
 

types/validator_set_test.go

@@ -392,10 +392,16 @@ func TestAveragingInIncrementProposerPriority(t *testing.T) {
 func TestAveragingInIncrementProposerPriorityWithVotingPower(t *testing.T) {
 	// Other than TestAveragingInIncrementProposerPriority this is a more complete test showing
 	// how each ProposerPriority changes in relation to the validator's voting power respectively.
+	// average is zero in each round:
+	vp0 := int64(10)
+	vp1 := int64(1)
+	vp2 := int64(1)
+	total := vp0 + vp1 + vp2
+	avg := (vp0 + vp1 + vp2 - total) / 3
 	vals := ValidatorSet{Validators: []*Validator{
-		{Address: []byte{0}, ProposerPriority: 0, VotingPower: 10},
-		{Address: []byte{1}, ProposerPriority: 0, VotingPower: 1},
-		{Address: []byte{2}, ProposerPriority: 0, VotingPower: 1}}}
+		{Address: []byte{0}, ProposerPriority: 0, VotingPower: vp0},
+		{Address: []byte{1}, ProposerPriority: 0, VotingPower: vp1},
+		{Address: []byte{2}, ProposerPriority: 0, VotingPower: vp2}}}
 	tcs := []struct {
 		vals                  *ValidatorSet
 		wantProposerPrioritys []int64
@@ -407,95 +413,89 @@ func TestAveragingInIncrementProposerPriorityWithVotingPower(t *testing.T) {
 			vals.Copy(),
 			[]int64{
 				// Acumm+VotingPower-Avg:
-				0 + 10 - 12 - 4, // mostest will be subtracted by total voting power (12)
-				0 + 1 - 4,
-				0 + 1 - 4},
+				0 + vp0 - total - avg, // mostest will be subtracted by total voting power (12)
+				0 + vp1,
+				0 + vp2},
 			1,
 			vals.Validators[0]},
 		1: {
 			vals.Copy(),
 			[]int64{
-				(0 + 10 - 12 - 4) + 10 - 12 + 4, // this will be mostest on 2nd iter, too
-				(0 + 1 - 4) + 1 + 4,
-				(0 + 1 - 4) + 1 + 4},
+				(0 + vp0 - total) + vp0 - total - avg, // this will be mostest on 2nd iter, too
+				(0 + vp1) + vp1,
+				(0 + vp2) + vp2},
 			2,
 			vals.Validators[0]}, // increment twice -> expect average to be subtracted twice
 		2: {
 			vals.Copy(),
 			[]int64{
-				((0 + 10 - 12 - 4) + 10 - 12) + 10 - 12 + 4, // still mostest
-				((0 + 1 - 4) + 1) + 1 + 4,
-				((0 + 1 - 4) + 1) + 1 + 4},
+				0 + 3*(vp0-total) - avg, // still mostest
+				0 + 3*vp1,
+				0 + 3*vp2},
 			3,
 			vals.Validators[0]},
 		3: {
 			vals.Copy(),
 			[]int64{
-				0 + 4*(10-12) + 4 - 4, // still mostest
-				0 + 4*1 + 4 - 4,
-				0 + 4*1 + 4 - 4},
+				0 + 4*(vp0-total), // still mostest
+				0 + 4*vp1,
+				0 + 4*vp2},
 			4,
 			vals.Validators[0]},
 		4: {
 			vals.Copy(),
 			[]int64{
-				0 + 4*(10-12) + 10 + 4 - 4, // 4 iters was mostest
-				0 + 5*1 - 12 + 4 - 4,       // now this val is mostest for the 1st time (hence -12==totalVotingPower)
-				0 + 5*1 + 4 - 4},
+				0 + 4*(vp0-total) + vp0, // 4 iters was mostest
+				0 + 5*vp1 - total,       // now this val is mostest for the 1st time (hence -12==totalVotingPower)
+				0 + 5*vp2},
 			5,
 			vals.Validators[1]},
 		5: {
 			vals.Copy(),
 			[]int64{
-				0 + 6*10 - 5*12 + 4 - 4, // mostest again
-				0 + 6*1 - 12 + 4 - 4,    // mostest once up to here
-				0 + 6*1 + 4 - 4},
+				0 + 6*vp0 - 5*total, // mostest again
+				0 + 6*vp1 - total,   // mostest once up to here
+				0 + 6*vp2},
 			6,
 			vals.Validators[0]},
 		6: {
 			vals.Copy(),
 			[]int64{
-				0 + 7*10 - 6*12 + 4 - 4, // in 7 iters this val is mostest 6 times
-				0 + 7*1 - 12 + 4 - 4,    // in 7 iters this val is mostest 1 time
-				0 + 7*1 + 4 - 4},
+				0 + 7*vp0 - 6*total, // in 7 iters this val is mostest 6 times
+				0 + 7*vp1 - total,   // in 7 iters this val is mostest 1 time
+				0 + 7*vp2},
 			7,
 			vals.Validators[0]},
 		7: {
 			vals.Copy(),
 			[]int64{
-				0 + 8*10 - 7*12 + 4 - 4, // mostest
-				0 + 8*1 - 12 + 4 - 4,
-				0 + 8*1 + 4 - 4},
+				0 + 8*vp0 - 7*total, // mostest again
+				0 + 8*vp1 - total,
+				0 + 8*vp2},
 			8,
 			vals.Validators[0]},
 		8: {
 			vals.Copy(),
 			[]int64{
-				0 + 9*10 - 7*12 + 4 - 4,
-				0 + 9*1 - 12 + 4 - 4,
-				0 + 9*1 - 12 + 4 - 4}, // mostest
+				0 + 9*vp0 - 7*total,
+				0 + 9*vp1 - total,
+				0 + 9*vp2 - total}, // mostest
 			9,
 			vals.Validators[2]},
 		9: {
 			vals.Copy(),
 			[]int64{
-				0 + 10*10 - 8*12 + 4 - 4, // after 10 iters this is mostest again
-				0 + 10*1 - 12 + 4 - 4,    // after 6 iters this val is "mostest" once and not in between
-				0 + 10*1 - 12 + 4 - 4},   // in between 10 iters this val is "mostest" once
+				0 + 10*vp0 - 8*total, // after 10 iters this is mostest again
+				0 + 10*vp1 - total,   // after 6 iters this val is "mostest" once and not in between
+				0 + 10*vp2 - total},  // in between 10 iters this val is "mostest" once
 			10,
 			vals.Validators[0]},
 		10: {
 			vals.Copy(),
 			[]int64{
-				// shift twice inside incrementProposerPriority (shift every 10th iter);
-				// don't shift at the end of IncremenctProposerPriority
-				// last avg should be zero because
-				// ProposerPriority of validator 0: (0 + 11*10 - 8*12 - 4) == 10
-				// ProposerPriority of validator 1 and 2: (0 + 11*1 - 12 - 4) == -5
-				// and (10 + 5 - 5) / 3 == 0
-				0 + 11*10 - 8*12 - 4 - 12 - 0,
-				0 + 11*1 - 12 - 4 - 0,  // after 6 iters this val is "mostest" once and not in between
-				0 + 11*1 - 12 - 4 - 0}, // after 10 iters this val is "mostest" once
+				0 + 11*vp0 - 9*total,
+				0 + 11*vp1 - total,  // after 6 iters this val is "mostest" once and not in between
+				0 + 11*vp2 - total}, // after 10 iters this val is "mostest" once
 			11,
 			vals.Validators[0]},
 	}

types/vote.go

@@ -52,8 +52,8 @@ type Vote struct {
 	Type             SignedMsgType `json:"type"`
 	Height           int64         `json:"height"`
 	Round            int           `json:"round"`
-	Timestamp        time.Time     `json:"timestamp"`
 	BlockID          BlockID       `json:"block_id"` // zero if vote is nil.
+	Timestamp        time.Time     `json:"timestamp"`
 	ValidatorAddress Address       `json:"validator_address"`
 	ValidatorIndex   int           `json:"validator_index"`
 	Signature        []byte        `json:"signature"`
@@ -127,6 +127,11 @@ func (vote *Vote) ValidateBasic() error {
 	if err := vote.BlockID.ValidateBasic(); err != nil {
 		return fmt.Errorf("Wrong BlockID: %v", err)
 	}
+	// BlockID.ValidateBasic would not err if we for instance have an empty hash but a
+	// non-empty PartsSetHeader:
+	if !vote.BlockID.IsZero() && !vote.BlockID.IsComplete() {
+		return fmt.Errorf("BlockID must be either empty or complete, got: %v", vote.BlockID)
+	}
 	if len(vote.ValidatorAddress) != crypto.AddressSize {
 		return fmt.Errorf("Expected ValidatorAddress size to be %d bytes, got %d bytes",
 			crypto.AddressSize,

types/vote_test.go

@@ -63,8 +63,8 @@ func TestVoteSignableTestVectors(t *testing.T) {
 		{
 			CanonicalizeVote("", &Vote{}),
 			// NOTE: Height and Round are skipped here. This case needs to be considered while parsing.
-			// []byte{0x22, 0x9, 0x9, 0x0, 0x9, 0x6e, 0x88, 0xf1, 0xff, 0xff, 0xff},
-			[]byte{0x22, 0xb, 0x8, 0x80, 0x92, 0xb8, 0xc3, 0x98, 0xfe, 0xff, 0xff, 0xff, 0x1},
+			// []byte{0x2a, 0x9, 0x9, 0x0, 0x9, 0x6e, 0x88, 0xf1, 0xff, 0xff, 0xff},
+			[]byte{0x2a, 0xb, 0x8, 0x80, 0x92, 0xb8, 0xc3, 0x98, 0xfe, 0xff, 0xff, 0xff, 0x1},
 		},
 		// with proper (fixed size) height and round (PreCommit):
 		{
@@ -76,7 +76,7 @@ func TestVoteSignableTestVectors(t *testing.T) {
 				0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, // height
 				0x19,                                   // (field_number << 3) | wire_type
 				0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, // round
-				0x22, // (field_number << 3) | wire_type
+				0x2a, // (field_number << 3) | wire_type
 				// remaining fields (timestamp):
 				0xb, 0x8, 0x80, 0x92, 0xb8, 0xc3, 0x98, 0xfe, 0xff, 0xff, 0xff, 0x1},
 		},
@@ -90,7 +90,7 @@ func TestVoteSignableTestVectors(t *testing.T) {
 				0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, // height
 				0x19,                                   // (field_number << 3) | wire_type
 				0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, // round
-				0x22, // (field_number << 3) | wire_type
+				0x2a, // (field_number << 3) | wire_type
 				// remaining fields (timestamp):
 				0xb, 0x8, 0x80, 0x92, 0xb8, 0xc3, 0x98, 0xfe, 0xff, 0xff, 0xff, 0x1},
 		},
@@ -102,7 +102,7 @@ func TestVoteSignableTestVectors(t *testing.T) {
 				0x19,                                   // (field_number << 3) | wire_type
 				0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, // round
 				// remaining fields (timestamp):
-				0x22,
+				0x2a,
 				0xb, 0x8, 0x80, 0x92, 0xb8, 0xc3, 0x98, 0xfe, 0xff, 0xff, 0xff, 0x1},
 		},
 		// containing non-empty chain_id:
@@ -114,7 +114,7 @@ func TestVoteSignableTestVectors(t *testing.T) {
 				0x19,                                   // (field_number << 3) | wire_type
 				0x1, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, // round
 				// remaining fields:
-				0x22,                                                                // (field_number << 3) | wire_type
+				0x2a,                                                                // (field_number << 3) | wire_type
 				0xb, 0x8, 0x80, 0x92, 0xb8, 0xc3, 0x98, 0xfe, 0xff, 0xff, 0xff, 0x1, // timestamp
 				0x32,                                                                               // (field_number << 3) | wire_type
 				0xd, 0x74, 0x65, 0x73, 0x74, 0x5f, 0x63, 0x68, 0x61, 0x69, 0x6e, 0x5f, 0x69, 0x64}, // chainID

version/version.go

@@ -18,7 +18,7 @@ const (
 	// TMCoreSemVer is the current version of Tendermint Core.
 	// It's the Semantic Version of the software.
 	// Must be a string because scripts like dist.sh read this file.
-	TMCoreSemVer = "0.28.1"
+	TMCoreSemVer = "0.29.0"
 
 	// ABCISemVer is the semantic version of the ABCI library
 	ABCISemVer  = "0.15.0"
@@ -36,10 +36,10 @@ func (p Protocol) Uint64() uint64 {
 
 var (
 	// P2PProtocol versions all p2p behaviour and msgs.
-	P2PProtocol Protocol = 5
+	P2PProtocol Protocol = 6
 
 	// BlockProtocol versions all block data structures and processing.
-	BlockProtocol Protocol = 8
+	BlockProtocol Protocol = 9
 )
 
 //------------------------------------------------------------------------