TMHASH is 32 bytes. Closes #1990 (#2732)

* tmhash is fully 32 bytes. closes #1990

* AddressSize

* fix tests

* fix max sizes

crypto/crypto.go

@@ -1,21 +1,23 @@
 package crypto
 
 import (
+	"github.com/tendermint/tendermint/crypto/tmhash"
 	cmn "github.com/tendermint/tendermint/libs/common"
 )
 
-type PrivKey interface {
-	Bytes() []byte
-	Sign(msg []byte) ([]byte, error)
-	PubKey() PubKey
-	Equals(PrivKey) bool
-}
+const (
+	AddressSize = tmhash.TruncatedSize
+)
 
 // An address is a []byte, but hex-encoded even in JSON.
 // []byte leaves us the option to change the address length.
 // Use an alias so Unmarshal methods (with ptr receivers) are available too.
 type Address = cmn.HexBytes
 
+func AddressHash(bz []byte) Address {
+	return Address(tmhash.SumTruncated(bz))
+}
+
 type PubKey interface {
 	Address() Address
 	Bytes() []byte
@@ -23,6 +25,13 @@ type PubKey interface {
 	Equals(PubKey) bool
 }
 
+type PrivKey interface {
+	Bytes() []byte
+	Sign(msg []byte) ([]byte, error)
+	PubKey() PubKey
+	Equals(PrivKey) bool
+}
+
 type Symmetric interface {
 	Keygen() []byte
 	Encrypt(plaintext []byte, secret []byte) (ciphertext []byte)

crypto/ed25519/ed25519.go

@@ -136,7 +136,7 @@ type PubKeyEd25519 [PubKeyEd25519Size]byte
 
 // Address is the SHA256-20 of the raw pubkey bytes.
 func (pubKey PubKeyEd25519) Address() crypto.Address {
-	return crypto.Address(tmhash.Sum(pubKey[:]))
+	return crypto.Address(tmhash.SumTruncated(pubKey[:]))
 }
 
 // Bytes marshals the PubKey using amino encoding.

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"}, "fa9bc106ffd932d919bee935ceb6cf2b3dd72d8f"},
-		{[]string{"key1"}, []string{"value2"}, "e00e7dcfe54e9fafef5111e813a587f01ba9c3e8"},
+		{[]string{"key1"}, []string{"value1"}, "321d150de16dceb51c72981b432b115045383259b1a550adf8dc80f927508967"},
+		{[]string{"key1"}, []string{"value2"}, "2a9e4baf321eac99f6eecc3406603c14bc5e85bb7b80483cbfc75b3382d24a2f"},
 		// swap order with 2 keys
-		{[]string{"key1", "key2"}, []string{"value1", "value2"}, "eff12d1c703a1022ab509287c0f196130123d786"},
-		{[]string{"key2", "key1"}, []string{"value2", "value1"}, "eff12d1c703a1022ab509287c0f196130123d786"},
+		{[]string{"key1", "key2"}, []string{"value1", "value2"}, "c4d8913ab543ba26aa970646d4c99a150fd641298e3367cf68ca45fb45a49881"},
+		{[]string{"key2", "key1"}, []string{"value2", "value1"}, "c4d8913ab543ba26aa970646d4c99a150fd641298e3367cf68ca45fb45a49881"},
 		// swap order with 3 keys
-		{[]string{"key1", "key2", "key3"}, []string{"value1", "value2", "value3"}, "b2c62a277c08dbd2ad73ca53cd1d6bfdf5830d26"},
-		{[]string{"key1", "key3", "key2"}, []string{"value1", "value3", "value2"}, "b2c62a277c08dbd2ad73ca53cd1d6bfdf5830d26"},
+		{[]string{"key1", "key2", "key3"}, []string{"value1", "value2", "value3"}, "b23cef00eda5af4548a213a43793f2752d8d9013b3f2b64bc0523a4791196268"},
+		{[]string{"key1", "key3", "key2"}, []string{"value1", "value3", "value2"}, "b23cef00eda5af4548a213a43793f2752d8d9013b3f2b64bc0523a4791196268"},
 	}
 	for i, tc := range tests {
 		db := newSimpleMap()

crypto/tmhash/hash.go

@@ -6,10 +6,27 @@ import (
 )
 
 const (
-	Size      = 20
+	Size      = sha256.Size
 	BlockSize = sha256.BlockSize
 )
 
+// New returns a new hash.Hash.
+func New() hash.Hash {
+	return sha256.New()
+}
+
+// Sum returns the SHA256 of the bz.
+func Sum(bz []byte) []byte {
+	h := sha256.Sum256(bz)
+	return h[:]
+}
+
+//-------------------------------------------------------------
+
+const (
+	TruncatedSize = 20
+)
+
 type sha256trunc struct {
 	sha256 hash.Hash
 }
@@ -19,7 +36,7 @@ func (h sha256trunc) Write(p []byte) (n int, err error) {
 }
 func (h sha256trunc) Sum(b []byte) []byte {
 	shasum := h.sha256.Sum(b)
-	return shasum[:Size]
+	return shasum[:TruncatedSize]
 }
 
 func (h sha256trunc) Reset() {
@@ -27,22 +44,22 @@ func (h sha256trunc) Reset() {
 }
 
 func (h sha256trunc) Size() int {
-	return Size
+	return TruncatedSize
 }
 
 func (h sha256trunc) BlockSize() int {
 	return h.sha256.BlockSize()
 }
 
-// New returns a new hash.Hash.
-func New() hash.Hash {
+// NewTruncated returns a new hash.Hash.
+func NewTruncated() hash.Hash {
 	return sha256trunc{
 		sha256: sha256.New(),
 	}
 }
 
-// Sum returns the first 20 bytes of SHA256 of the bz.
-func Sum(bz []byte) []byte {
+// SumTruncated returns the first 20 bytes of SHA256 of the bz.
+func SumTruncated(bz []byte) []byte {
 	hash := sha256.Sum256(bz)
-	return hash[:Size]
+	return hash[:TruncatedSize]
 }

crypto/tmhash/hash_test.go

@@ -14,10 +14,29 @@ func TestHash(t *testing.T) {
 	hasher.Write(testVector)
 	bz := hasher.Sum(nil)
 
+	bz2 := tmhash.Sum(testVector)
+
 	hasher = sha256.New()
 	hasher.Write(testVector)
-	bz2 := hasher.Sum(nil)
-	bz2 = bz2[:20]
+	bz3 := hasher.Sum(nil)
 
 	assert.Equal(t, bz, bz2)
+	assert.Equal(t, bz, bz3)
+}
+
+func TestHashTruncated(t *testing.T) {
+	testVector := []byte("abc")
+	hasher := tmhash.NewTruncated()
+	hasher.Write(testVector)
+	bz := hasher.Sum(nil)
+
+	bz2 := tmhash.SumTruncated(testVector)
+
+	hasher = sha256.New()
+	hasher.Write(testVector)
+	bz3 := hasher.Sum(nil)
+	bz3 = bz3[:tmhash.TruncatedSize]
+
+	assert.Equal(t, bz, bz2)
+	assert.Equal(t, bz, bz3)
 }

docs/spec/blockchain/blockchain.md

@@ -344,7 +344,7 @@ next validator sets Merkle root.
 ### ConsensusParamsHash
 
 ```go
-block.ConsensusParamsHash == tmhash(amino(state.ConsensusParams))
+block.ConsensusParamsHash == TMHASH(amino(state.ConsensusParams))
 ```
 
 Hash of the amino-encoded consensus parameters.

docs/spec/blockchain/encoding.md

@@ -176,13 +176,12 @@ greater, for example:
 h0  h1          h3  h4             h0  h1  h2  h3  h4  h5
 ```
 
-Tendermint always uses the `TMHASH` hash function, which is the first 20-bytes
-of the SHA256:
+Tendermint always uses the `TMHASH` hash function, which is equivalent to
+SHA256:
 
 ```
 func TMHASH(bz []byte) []byte {
-    shasum := SHA256(bz)
-    return shasum[:20]
+    return SHA256(bz)
 }
 ```
 

docs/spec/blockchain/state.md

@@ -56,8 +56,8 @@ type Validator struct {
 }
 ```
 
-When hashing the Validator struct, the pubkey is not hashed,
-because the address is already the hash of the pubkey.
+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.

p2p/key.go

@@ -8,7 +8,6 @@ import (
 
 	crypto "github.com/tendermint/tendermint/crypto"
 	"github.com/tendermint/tendermint/crypto/ed25519"
-	"github.com/tendermint/tendermint/crypto/tmhash"
 	cmn "github.com/tendermint/tendermint/libs/common"
 )
 
@@ -17,7 +16,7 @@ type ID string
 
 // IDByteLength is the length of a crypto.Address. Currently only 20.
 // TODO: support other length addresses ?
-const IDByteLength = tmhash.Size
+const IDByteLength = crypto.AddressSize
 
 //------------------------------------------------------------------------------
 // Persistent peer ID

state/validation.go

@@ -5,7 +5,7 @@ import (
 	"errors"
 	"fmt"
 
-	"github.com/tendermint/tendermint/crypto/tmhash"
+	"github.com/tendermint/tendermint/crypto"
 	dbm "github.com/tendermint/tendermint/libs/db"
 	"github.com/tendermint/tendermint/types"
 )
@@ -158,7 +158,7 @@ func validateBlock(stateDB dbm.DB, state State, block *types.Block) error {
 	// NOTE: We can't actually verify it's the right proposer because we dont
 	// know what round the block was first proposed. So just check that it's
 	// a legit address and a known validator.
-	if len(block.ProposerAddress) != tmhash.Size ||
+	if len(block.ProposerAddress) != crypto.AddressSize ||
 		!state.Validators.HasAddress(block.ProposerAddress) {
 		return fmt.Errorf(
 			"Block.Header.ProposerAddress, %X, is not a validator",

types/block.go

@@ -15,7 +15,7 @@ import (
 
 const (
 	// MaxHeaderBytes is a maximum header size (including amino overhead).
-	MaxHeaderBytes int64 = 533
+	MaxHeaderBytes int64 = 653
 
 	// MaxAminoOverheadForBlock - maximum amino overhead to encode a block (up to
 	// MaxBlockSizeBytes in size) not including it's parts except Data.

types/block_test.go

@@ -10,6 +10,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
+	"github.com/tendermint/tendermint/crypto"
 	"github.com/tendermint/tendermint/crypto/tmhash"
 	cmn "github.com/tendermint/tendermint/libs/common"
 	"github.com/tendermint/tendermint/version"
@@ -116,7 +117,7 @@ func TestBlockMakePartSetWithEvidence(t *testing.T) {
 
 	partSet := MakeBlock(h, []Tx{Tx("Hello World")}, commit, evList).MakePartSet(1024)
 	assert.NotNil(t, partSet)
-	assert.Equal(t, 2, partSet.Total())
+	assert.Equal(t, 3, partSet.Total())
 }
 
 func TestBlockHashesTo(t *testing.T) {
@@ -262,7 +263,7 @@ func TestMaxHeaderBytes(t *testing.T) {
 		AppHash:            tmhash.Sum([]byte("app_hash")),
 		LastResultsHash:    tmhash.Sum([]byte("last_results_hash")),
 		EvidenceHash:       tmhash.Sum([]byte("evidence_hash")),
-		ProposerAddress:    tmhash.Sum([]byte("proposer_address")),
+		ProposerAddress:    crypto.AddressHash([]byte("proposer_address")),
 	}
 
 	bz, err := cdc.MarshalBinaryLengthPrefixed(h)
@@ -292,9 +293,9 @@ func TestBlockMaxDataBytes(t *testing.T) {
 	}{
 		0: {-10, 1, 0, true, 0},
 		1: {10, 1, 0, true, 0},
-		2: {742, 1, 0, true, 0},
-		3: {743, 1, 0, false, 0},
-		4: {744, 1, 0, false, 1},
+		2: {886, 1, 0, true, 0},
+		3: {887, 1, 0, false, 0},
+		4: {888, 1, 0, false, 1},
 	}
 
 	for i, tc := range testCases {
@@ -320,9 +321,9 @@ func TestBlockMaxDataBytesUnknownEvidence(t *testing.T) {
 	}{
 		0: {-10, 1, true, 0},
 		1: {10, 1, true, 0},
-		2: {824, 1, true, 0},
-		3: {825, 1, false, 0},
-		4: {826, 1, false, 1},
+		2: {984, 1, true, 0},
+		3: {985, 1, false, 0},
+		4: {986, 1, false, 1},
 	}
 
 	for i, tc := range testCases {

types/evidence.go

@@ -14,7 +14,7 @@ import (
 
 const (
 	// MaxEvidenceBytes is a maximum size of any evidence (including amino overhead).
-	MaxEvidenceBytes int64 = 436
+	MaxEvidenceBytes int64 = 484
 )
 
 // ErrEvidenceInvalid wraps a piece of evidence and the error denoting how or why it is invalid.

types/validator.go

@@ -77,15 +77,15 @@ func (v *Validator) Hash() []byte {
 }
 
 // Bytes computes the unique encoding of a validator with a given voting power.
-// These are the bytes that gets hashed in consensus. It excludes pubkey
-// as its redundant with the address. This also excludes accum which changes
+// These are the bytes that gets hashed in consensus. It excludes address
+// as its redundant with the pubkey. This also excludes accum which changes
 // every round.
 func (v *Validator) Bytes() []byte {
 	return cdcEncode((struct {
-		Address     Address
+		PubKey      crypto.PubKey
 		VotingPower int64
 	}{
-		v.Address,
+		v.PubKey,
 		v.VotingPower,
 	}))
 }

types/vote.go

@@ -12,7 +12,7 @@ import (
 
 const (
 	// MaxVoteBytes is a maximum vote size (including amino overhead).
-	MaxVoteBytes int64 = 199
+	MaxVoteBytes int64 = 223
 )
 
 var (

types/vote_test.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"github.com/tendermint/tendermint/crypto"
 	"github.com/tendermint/tendermint/crypto/ed25519"
 	"github.com/tendermint/tendermint/crypto/tmhash"
 )
@@ -37,7 +38,7 @@ func exampleVote(t byte) *Vote {
 				Hash:  tmhash.Sum([]byte("blockID_part_set_header_hash")),
 			},
 		},
-		ValidatorAddress: tmhash.Sum([]byte("validator_address")),
+		ValidatorAddress: crypto.AddressHash([]byte("validator_address")),
 		ValidatorIndex:   56789,
 	}
 }
@@ -211,7 +212,7 @@ func TestMaxVoteBytes(t *testing.T) {
 	timestamp := time.Date(math.MaxInt64, 0, 0, 0, 0, 0, math.MaxInt64, time.UTC)
 
 	vote := &Vote{
-		ValidatorAddress: tmhash.Sum([]byte("validator_address")),
+		ValidatorAddress: crypto.AddressHash([]byte("validator_address")),
 		ValidatorIndex:   math.MaxInt64,
 		Height:           math.MaxInt64,
 		Round:            math.MaxInt64,