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light: implement light block (#5298)

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This commit is contained in:
Callum Waters
2020-09-01 17:45:55 +02:00
committed by GitHub
parent b6a5f7b126
commit 2b58a62721
25 changed files with 1343 additions and 1196 deletions
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273
light/client_test.go
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@@ -53,6 +53,8 @@ var (
// last header (3/3 signed)
3: h3,
}
l1 = &types.LightBlock{SignedHeader: h1, ValidatorSet: vals}
l2 = &types.LightBlock{SignedHeader: h2, ValidatorSet: vals}
fullNode = mockp.New(
chainID,
headerSet,
@@ -108,6 +110,11 @@ func TestValidateTrustOptions(t *testing.T) {
}
func TestMock(t *testing.T) {
l, _ := fullNode.LightBlock(3)
assert.Equal(t, int64(3), l.Height)
}
func TestClient_SequentialVerification(t *testing.T) {
newKeys := genPrivKeys(4)
newVals := newKeys.ToValidators(10, 1)
@@ -212,7 +219,7 @@ func TestClient_SequentialVerification(t *testing.T) {
require.NoError(t, err)
_, err = c.VerifyHeaderAtHeight(3, bTime.Add(3*time.Hour))
_, err = c.VerifyLightBlockAtHeight(3, bTime.Add(3*time.Hour))
if tc.verifyErr {
assert.Error(t, err)
} else {
@@ -335,7 +342,7 @@ func TestClient_SkippingVerification(t *testing.T) {
require.NoError(t, err)
_, err = c.VerifyHeaderAtHeight(3, bTime.Add(3*time.Hour))
_, err = c.VerifyLightBlockAtHeight(3, bTime.Add(3*time.Hour))
if tc.verifyErr {
assert.Error(t, err)
} else {
@@ -346,18 +353,18 @@ func TestClient_SkippingVerification(t *testing.T) {
}
// start from a large header to make sure that the pivot height doesn't select a height outside
// start from a large light block to make sure that the pivot height doesn't select a height outside
// the appropriate range
func TestClientLargeBisectionVerification(t *testing.T) {
veryLargeFullNode := mockp.New(GenMockNode(chainID, 100, 3, 1, bTime))
h1, err := veryLargeFullNode.SignedHeader(90)
l1, err := veryLargeFullNode.LightBlock(90)
require.NoError(t, err)
c, err := light.NewClient(
chainID,
light.TrustOptions{
Period: 4 * time.Hour,
Height: 90,
Hash: h1.Hash(),
Height: l1.Height,
Hash: l1.Hash(),
},
veryLargeFullNode,
[]provider.Provider{veryLargeFullNode},
@@ -367,7 +374,7 @@ func TestClientLargeBisectionVerification(t *testing.T) {
require.NoError(t, err)
h, err := c.Update(bTime.Add(100 * time.Minute))
assert.NoError(t, err)
h2, err := veryLargeFullNode.SignedHeader(100)
h2, err := veryLargeFullNode.LightBlock(100)
require.NoError(t, err)
assert.Equal(t, h, h2)
}
@@ -387,15 +394,15 @@ func TestClientBisectionBetweenTrustedHeaders(t *testing.T) {
)
require.NoError(t, err)
_, err = c.VerifyHeaderAtHeight(3, bTime.Add(2*time.Hour))
_, err = c.VerifyLightBlockAtHeight(3, bTime.Add(2*time.Hour))
require.NoError(t, err)
// confirm that the client already doesn't have the header
_, err = c.TrustedHeader(2)
// confirm that the client already doesn't have the light block
_, err = c.TrustedLightBlock(2)
require.Error(t, err)
// verify using bisection the header between the two trusted headers
_, err = c.VerifyHeaderAtHeight(2, bTime.Add(1*time.Hour))
// verify using bisection the light block between the two trusted light blocks
_, err = c.VerifyLightBlockAtHeight(2, bTime.Add(1*time.Hour))
assert.NoError(t, err)
}
@@ -409,20 +416,16 @@ func TestClient_Cleanup(t *testing.T) {
light.Logger(log.TestingLogger()),
)
require.NoError(t, err)
_, err = c.TrustedHeader(1)
_, err = c.TrustedLightBlock(1)
require.NoError(t, err)
err = c.Cleanup()
require.NoError(t, err)
// Check no headers/valsets exist after Cleanup.
h, err := c.TrustedHeader(1)
// Check no light blocks exist after Cleanup.
l, err := c.TrustedLightBlock(1)
assert.Error(t, err)
assert.Nil(t, h)
valSet, _, err := c.TrustedValidatorSet(1)
assert.Error(t, err)
assert.Nil(t, valSet)
assert.Nil(t, l)
}
// trustedHeader.Height == options.Height
@@ -430,7 +433,7 @@ func TestClientRestoresTrustedHeaderAfterStartup1(t *testing.T) {
// 1. options.Hash == trustedHeader.Hash
{
trustedStore := dbs.New(dbm.NewMemDB(), chainID)
err := trustedStore.SaveSignedHeaderAndValidatorSet(h1, vals)
err := trustedStore.SaveLightBlock(l1)
require.NoError(t, err)
c, err := light.NewClient(
@@ -443,23 +446,17 @@ func TestClientRestoresTrustedHeaderAfterStartup1(t *testing.T) {
)
require.NoError(t, err)
h, err := c.TrustedHeader(1)
l, err := c.TrustedLightBlock(1)
assert.NoError(t, err)
assert.NotNil(t, h)
assert.Equal(t, h.Hash(), h1.Hash())
valSet, _, err := c.TrustedValidatorSet(1)
assert.NoError(t, err)
assert.NotNil(t, valSet)
if assert.NotNil(t, valSet) {
assert.Equal(t, h.ValidatorsHash.Bytes(), valSet.Hash())
}
assert.NotNil(t, l)
assert.Equal(t, l.Hash(), h1.Hash())
assert.Equal(t, l.ValidatorSet.Hash(), h1.ValidatorsHash.Bytes())
}
// 2. options.Hash != trustedHeader.Hash
{
trustedStore := dbs.New(dbm.NewMemDB(), chainID)
err := trustedStore.SaveSignedHeaderAndValidatorSet(h1, vals)
err := trustedStore.SaveLightBlock(l1)
require.NoError(t, err)
// header1 != header
@@ -489,17 +486,11 @@ func TestClientRestoresTrustedHeaderAfterStartup1(t *testing.T) {
)
require.NoError(t, err)
h, err := c.TrustedHeader(1)
l, err := c.TrustedLightBlock(1)
assert.NoError(t, err)
if assert.NotNil(t, h) {
assert.Equal(t, h.Hash(), header1.Hash())
}
valSet, _, err := c.TrustedValidatorSet(1)
assert.NoError(t, err)
assert.NotNil(t, valSet)
if assert.NotNil(t, valSet) {
assert.Equal(t, h.ValidatorsHash.Bytes(), valSet.Hash())
if assert.NotNil(t, l) {
assert.Equal(t, l.Hash(), header1.Hash())
assert.NoError(t, l.ValidateBasic(chainID))
}
}
}
@@ -509,7 +500,7 @@ func TestClientRestoresTrustedHeaderAfterStartup2(t *testing.T) {
// 1. options.Hash == trustedHeader.Hash
{
trustedStore := dbs.New(dbm.NewMemDB(), chainID)
err := trustedStore.SaveSignedHeaderAndValidatorSet(h1, vals)
err := trustedStore.SaveLightBlock(l1)
require.NoError(t, err)
c, err := light.NewClient(
@@ -527,24 +518,18 @@ func TestClientRestoresTrustedHeaderAfterStartup2(t *testing.T) {
require.NoError(t, err)
// Check we still have the 1st header (+header+).
h, err := c.TrustedHeader(1)
l, err := c.TrustedLightBlock(1)
assert.NoError(t, err)
assert.NotNil(t, h)
assert.Equal(t, h.Hash(), h1.Hash())
valSet, _, err := c.TrustedValidatorSet(1)
assert.NoError(t, err)
assert.NotNil(t, valSet)
if assert.NotNil(t, valSet) {
assert.Equal(t, h.ValidatorsHash.Bytes(), valSet.Hash())
}
assert.NotNil(t, l)
assert.Equal(t, l.Hash(), h1.Hash())
assert.NoError(t, l.ValidateBasic(chainID))
}
// 2. options.Hash != trustedHeader.Hash
// This could happen if previous provider was lying to us.
{
trustedStore := dbs.New(dbm.NewMemDB(), chainID)
err := trustedStore.SaveSignedHeaderAndValidatorSet(h1, vals)
err := trustedStore.SaveLightBlock(l1)
require.NoError(t, err)
// header1 != header
@@ -578,13 +563,9 @@ func TestClientRestoresTrustedHeaderAfterStartup2(t *testing.T) {
require.NoError(t, err)
// Check we no longer have the invalid 1st header (+header+).
h, err := c.TrustedHeader(1)
l, err := c.TrustedLightBlock(1)
assert.Error(t, err)
assert.Nil(t, h)
valSet, _, err := c.TrustedValidatorSet(1)
assert.Error(t, err)
assert.Nil(t, valSet)
assert.Nil(t, l)
}
}
@@ -594,10 +575,10 @@ func TestClientRestoresTrustedHeaderAfterStartup3(t *testing.T) {
{
// load the first three headers into the trusted store
trustedStore := dbs.New(dbm.NewMemDB(), chainID)
err := trustedStore.SaveSignedHeaderAndValidatorSet(h1, vals)
err := trustedStore.SaveLightBlock(l1)
require.NoError(t, err)
err = trustedStore.SaveSignedHeaderAndValidatorSet(h2, vals)
err = trustedStore.SaveLightBlock(l2)
require.NoError(t, err)
c, err := light.NewClient(
@@ -610,38 +591,28 @@ func TestClientRestoresTrustedHeaderAfterStartup3(t *testing.T) {
)
require.NoError(t, err)
// Check we still have the 1st header (+header+).
h, err := c.TrustedHeader(1)
// Check we still have the 1st light block.
l, err := c.TrustedLightBlock(1)
assert.NoError(t, err)
assert.NotNil(t, h)
assert.Equal(t, h.Hash(), h1.Hash())
assert.NotNil(t, l)
assert.Equal(t, l.Hash(), h1.Hash())
assert.NoError(t, l.ValidateBasic(chainID))
valSet, _, err := c.TrustedValidatorSet(1)
assert.NoError(t, err)
assert.NotNil(t, valSet)
if assert.NotNil(t, valSet) {
assert.Equal(t, h.ValidatorsHash.Bytes(), valSet.Hash())
}
// Check we no longer have 2nd header (+header2+).
h, err = c.TrustedHeader(2)
// Check we no longer have 2nd light block.
l, err = c.TrustedLightBlock(2)
assert.Error(t, err)
assert.Nil(t, h)
assert.Nil(t, l)
valSet, _, err = c.TrustedValidatorSet(2)
l, err = c.TrustedLightBlock(3)
assert.Error(t, err)
assert.Nil(t, valSet)
h, err = c.TrustedHeader(3)
assert.Error(t, err)
assert.Nil(t, h)
assert.Nil(t, l)
}
// 2. options.Hash != trustedHeader.Hash
// This could happen if previous provider was lying to us.
{
trustedStore := dbs.New(dbm.NewMemDB(), chainID)
err := trustedStore.SaveSignedHeaderAndValidatorSet(h1, vals)
err := trustedStore.SaveLightBlock(l1)
require.NoError(t, err)
// header1 != header
@@ -650,7 +621,10 @@ func TestClientRestoresTrustedHeaderAfterStartup3(t *testing.T) {
header2 := keys.GenSignedHeader(chainID, 2, bTime.Add(2*time.Hour), nil, vals, vals,
hash("app_hash"), hash("cons_hash"), hash("results_hash"), 0, len(keys))
err = trustedStore.SaveSignedHeaderAndValidatorSet(header2, vals)
err = trustedStore.SaveLightBlock(&types.LightBlock{
SignedHeader: header2,
ValidatorSet: vals,
})
require.NoError(t, err)
primary := mockp.New(
@@ -675,27 +649,17 @@ func TestClientRestoresTrustedHeaderAfterStartup3(t *testing.T) {
)
require.NoError(t, err)
// Check we have swapped invalid 1st header (+header+) with correct one (+header1+).
h, err := c.TrustedHeader(1)
// Check we have swapped invalid 1st light block (+lightblock+) with correct one (+lightblock2+).
l, err := c.TrustedLightBlock(1)
assert.NoError(t, err)
assert.NotNil(t, h)
assert.Equal(t, h.Hash(), header1.Hash())
assert.NotNil(t, l)
assert.Equal(t, l.Hash(), header1.Hash())
assert.NoError(t, l.ValidateBasic(chainID))
valSet, _, err := c.TrustedValidatorSet(1)
assert.NoError(t, err)
assert.NotNil(t, valSet)
if assert.NotNil(t, valSet) {
assert.Equal(t, h.ValidatorsHash.Bytes(), valSet.Hash())
}
// Check we no longer have invalid 2nd header (+header2+).
h, err = c.TrustedHeader(2)
// Check we no longer have invalid 2nd light block (+lightblock2+).
l, err = c.TrustedLightBlock(2)
assert.Error(t, err)
assert.Nil(t, h)
valSet, _, err = c.TrustedValidatorSet(2)
assert.Error(t, err)
assert.Nil(t, valSet)
assert.Nil(t, l)
}
}
@@ -711,16 +675,11 @@ func TestClient_Update(t *testing.T) {
require.NoError(t, err)
// should result in downloading & verifying header #3
h, err := c.Update(bTime.Add(2 * time.Hour))
l, err := c.Update(bTime.Add(2 * time.Hour))
assert.NoError(t, err)
if assert.NotNil(t, h) {
assert.EqualValues(t, 3, h.Height)
}
valSet, _, err := c.TrustedValidatorSet(3)
assert.NoError(t, err)
if assert.NotNil(t, valSet) {
assert.Equal(t, h.ValidatorsHash.Bytes(), valSet.Hash())
if assert.NotNil(t, l) {
assert.EqualValues(t, 3, l.Height)
assert.NoError(t, l.ValidateBasic(chainID))
}
}
@@ -735,7 +694,7 @@ func TestClient_Concurrency(t *testing.T) {
)
require.NoError(t, err)
_, err = c.VerifyHeaderAtHeight(2, bTime.Add(2*time.Hour))
_, err = c.VerifyLightBlockAtHeight(2, bTime.Add(2*time.Hour))
require.NoError(t, err)
var wg sync.WaitGroup
@@ -744,7 +703,7 @@ func TestClient_Concurrency(t *testing.T) {
go func() {
defer wg.Done()
// NOTE: Cleanup, Stop, VerifyHeaderAtHeight and Verify are not supposed
// NOTE: Cleanup, Stop, VerifyLightBlockAtHeight and Verify are not supposed
// to be concurrenly safe.
assert.Equal(t, chainID, c.ChainID())
@@ -755,13 +714,9 @@ func TestClient_Concurrency(t *testing.T) {
_, err = c.FirstTrustedHeight()
assert.NoError(t, err)
h, err := c.TrustedHeader(1)
l, err := c.TrustedLightBlock(1)
assert.NoError(t, err)
assert.NotNil(t, h)
vals, _, err := c.TrustedValidatorSet(2)
assert.NoError(t, err)
assert.NotNil(t, vals)
assert.NotNil(t, l)
}()
}
@@ -789,7 +744,7 @@ func TestClientReplacesPrimaryWithWitnessIfPrimaryIsUnavailable(t *testing.T) {
func TestClient_BackwardsVerification(t *testing.T) {
{
trustHeader, _ := largeFullNode.SignedHeader(6)
trustHeader, _ := largeFullNode.LightBlock(6)
c, err := light.NewClient(
chainID,
light.TrustOptions{
@@ -805,42 +760,38 @@ func TestClient_BackwardsVerification(t *testing.T) {
require.NoError(t, err)
// 1) verify before the trusted header using backwards => expect no error
h, err := c.VerifyHeaderAtHeight(5, bTime.Add(6*time.Minute))
h, err := c.VerifyLightBlockAtHeight(5, bTime.Add(6*time.Minute))
require.NoError(t, err)
if assert.NotNil(t, h) {
assert.EqualValues(t, 5, h.Height)
}
// 2) untrusted header is expired but trusted header is not => expect no error
h, err = c.VerifyHeaderAtHeight(3, bTime.Add(8*time.Minute))
h, err = c.VerifyLightBlockAtHeight(3, bTime.Add(8*time.Minute))
assert.NoError(t, err)
assert.NotNil(t, h)
// 3) already stored headers should return the header without error
h, err = c.VerifyHeaderAtHeight(5, bTime.Add(6*time.Minute))
h, err = c.VerifyLightBlockAtHeight(5, bTime.Add(6*time.Minute))
assert.NoError(t, err)
assert.NotNil(t, h)
// 4a) First verify latest header
_, err = c.VerifyHeaderAtHeight(9, bTime.Add(9*time.Minute))
_, err = c.VerifyLightBlockAtHeight(9, bTime.Add(9*time.Minute))
require.NoError(t, err)
// 4b) Verify backwards using bisection => expect no error
_, err = c.VerifyHeaderAtHeight(7, bTime.Add(10*time.Minute))
_, err = c.VerifyLightBlockAtHeight(7, bTime.Add(9*time.Minute))
assert.NoError(t, err)
// shouldn't have verified this header in the process
_, err = c.TrustedHeader(8)
_, err = c.TrustedLightBlock(8)
assert.Error(t, err)
// 5) trusted header has expired => expect error
_, err = c.VerifyHeaderAtHeight(1, bTime.Add(20*time.Minute))
// 5) Try bisection method, but closest header (at 7) has expired
// so expect error
_, err = c.VerifyLightBlockAtHeight(8, bTime.Add(12*time.Minute))
assert.Error(t, err)
// 6) Try bisection method, but closest header (at 7) has expired
// so change to backwards => expect no error
_, err = c.VerifyHeaderAtHeight(8, bTime.Add(12*time.Minute))
assert.NoError(t, err)
}
{
testCases := []struct {
@@ -852,7 +803,7 @@ func TestClient_BackwardsVerification(t *testing.T) {
chainID,
map[int64]*types.SignedHeader{
1: h1,
2: keys.GenSignedHeader(chainID, 1, bTime.Add(1*time.Hour), nil, vals, vals,
2: keys.GenSignedHeader(chainID, 1, bTime.Add(30*time.Minute), nil, vals, vals,
hash("app_hash"), hash("cons_hash"), hash("results_hash"), 0, len(keys)),
3: h3,
},
@@ -866,7 +817,7 @@ func TestClient_BackwardsVerification(t *testing.T) {
map[int64]*types.SignedHeader{
1: h1,
2: keys.GenSignedHeader(chainID, 2, bTime.Add(30*time.Minute), nil, vals, vals,
hash("app_hash"), hash("cons_hash"), hash("results_hash"), 0, len(keys)),
hash("app_hash2"), hash("cons_hash23"), hash("results_hash30"), 0, len(keys)),
3: h3,
},
valSet,
@@ -874,7 +825,7 @@ func TestClient_BackwardsVerification(t *testing.T) {
},
}
for _, tc := range testCases {
for idx, tc := range testCases {
c, err := light.NewClient(
chainID,
light.TrustOptions{
@@ -887,10 +838,10 @@ func TestClient_BackwardsVerification(t *testing.T) {
dbs.New(dbm.NewMemDB(), chainID),
light.Logger(log.TestingLogger()),
)
require.NoError(t, err)
require.NoError(t, err, idx)
_, err = c.VerifyHeaderAtHeight(2, bTime.Add(1*time.Hour).Add(1*time.Second))
assert.Error(t, err)
_, err = c.VerifyLightBlockAtHeight(2, bTime.Add(1*time.Hour).Add(1*time.Second))
assert.Error(t, err, idx)
}
}
}
@@ -898,7 +849,7 @@ func TestClient_BackwardsVerification(t *testing.T) {
func TestClient_NewClientFromTrustedStore(t *testing.T) {
// 1) Initiate DB and fill with a "trusted" header
db := dbs.New(dbm.NewMemDB(), chainID)
err := db.SaveSignedHeaderAndValidatorSet(h1, vals)
err := db.SaveLightBlock(l1)
require.NoError(t, err)
c, err := light.NewClientFromTrustedStore(
@@ -910,18 +861,11 @@ func TestClient_NewClientFromTrustedStore(t *testing.T) {
)
require.NoError(t, err)
// 2) Check header exists (deadNode is being used to ensure we're not getting
// 2) Check light block exists (deadNode is being used to ensure we're not getting
// it from primary)
h, err := c.TrustedHeader(1)
h, err := c.TrustedLightBlock(1)
assert.NoError(t, err)
assert.EqualValues(t, 1, h.Height)
valSet, _, err := c.TrustedValidatorSet(1)
assert.NoError(t, err)
assert.NotNil(t, valSet)
if assert.NotNil(t, valSet) {
assert.Equal(t, h.ValidatorsHash.Bytes(), valSet.Hash())
}
assert.EqualValues(t, l1.Height, h.Height)
}
func TestClientRemovesWitnessIfItSendsUsIncorrectHeader(t *testing.T) {
@@ -967,18 +911,18 @@ func TestClientRemovesWitnessIfItSendsUsIncorrectHeader(t *testing.T) {
assert.EqualValues(t, 2, len(c.Witnesses()))
// witness behaves incorrectly -> removed from list, no error
h, err := c.VerifyHeaderAtHeight(2, bTime.Add(2*time.Hour))
l, err := c.VerifyLightBlockAtHeight(2, bTime.Add(2*time.Hour))
assert.NoError(t, err)
assert.EqualValues(t, 1, len(c.Witnesses()))
// header should still be verified
assert.EqualValues(t, 2, h.Height)
// light block should still be verified
assert.EqualValues(t, 2, l.Height)
// remaining witnesses doesn't have header -> error
_, err = c.VerifyHeaderAtHeight(3, bTime.Add(2*time.Hour))
// remaining witnesses don't have light block -> error
_, err = c.VerifyLightBlockAtHeight(3, bTime.Add(2*time.Hour))
if assert.Error(t, err) {
assert.Equal(t, "awaiting response from all witnesses exceeded dropout time", err.Error())
}
// witness does not have a header -> left in the list
// witness does not have a light block -> left in the list
assert.EqualValues(t, 1, len(c.Witnesses()))
}
@@ -1017,21 +961,16 @@ func TestClient_TrustedValidatorSet(t *testing.T) {
chainID,
trustOptions,
noValSetNode,
[]provider.Provider{fullNode, badValSetNode, fullNode},
[]provider.Provider{badValSetNode, fullNode, fullNode},
dbs.New(dbm.NewMemDB(), chainID),
light.Logger(log.TestingLogger()),
)
require.NoError(t, err)
assert.Equal(t, 2, len(c.Witnesses()))
_, err = c.VerifyHeaderAtHeight(2, bTime.Add(2*time.Hour).Add(1*time.Second))
_, err = c.VerifyLightBlockAtHeight(2, bTime.Add(2*time.Hour).Add(1*time.Second))
assert.NoError(t, err)
assert.Equal(t, 1, len(c.Witnesses()))
valSet, height, err := c.TrustedValidatorSet(0)
assert.NoError(t, err)
assert.NotNil(t, valSet)
assert.EqualValues(t, 2, height)
}
func TestClientReportsConflictingHeadersEvidence(t *testing.T) {
@@ -1063,7 +1002,7 @@ func TestClientReportsConflictingHeadersEvidence(t *testing.T) {
require.NoError(t, err)
// Check verification returns an error.
_, err = c.VerifyHeaderAtHeight(2, bTime.Add(2*time.Hour))
_, err = c.VerifyLightBlockAtHeight(2, bTime.Add(2*time.Hour))
if assert.Error(t, err) {
assert.Contains(t, err.Error(), "does not match one")
}
@@ -1085,14 +1024,14 @@ func TestClientPrunesHeadersAndValidatorSets(t *testing.T) {
light.PruningSize(1),
)
require.NoError(t, err)
_, err = c.TrustedHeader(1)
_, err = c.TrustedLightBlock(1)
require.NoError(t, err)
h, err := c.Update(bTime.Add(2 * time.Hour))
require.NoError(t, err)
require.Equal(t, int64(3), h.Height)
_, err = c.TrustedHeader(1)
_, err = c.TrustedLightBlock(1)
assert.Error(t, err)
}
@@ -1157,7 +1096,7 @@ func TestClientEnsureValidHeadersAndValSets(t *testing.T) {
)
require.NoError(t, err)
_, err = c.VerifyHeaderAtHeight(3, bTime.Add(2*time.Hour))
_, err = c.VerifyLightBlockAtHeight(3, bTime.Add(2*time.Hour))
if tc.err {
assert.Error(t, err)
} else {