rpc: enforce BIP 145 SegWit rules in getblocktemplate - #2569
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Approach looks good, reversing rpcserver.go causes all the three added integration tests to fail, and confirmed the behavior of getblocktemplate against Bitcoin Core.
There's a broken test here:
=== RUN TestHelp
rpcserverhelp_test.go:43: Failed to generate help for method 'getblocktemplate': getblocktemplateresult-rules
--- FAIL: TestHelp (0.00s)
There's also some formatting changes and minor code readability improvements in the diff below. I know that not all the code is following the formatting rules, but I think that would be nice to at least follow them in the lines we modify. Thanks for the PR.
diff --git a/integration/rpcserver_test.go b/integration/rpcserver_test.go
index c7f52cef..ee34f173 100644
--- a/integration/rpcserver_test.go
+++ b/integration/rpcserver_test.go
@@ -299,8 +299,12 @@ func ensureSegwitActive(r *rpctest.Harness, t *testing.T) {
t.Fatalf("unable to get blockchain info: %v", err)
}
- if info.Bip9SoftForks == nil || info.Bip9SoftForks["segwit"] == nil {
- t.Fatalf("segwit softfork status not found in blockchain info")
+ if info.Bip9SoftForks == nil ||
+ info.Bip9SoftForks["segwit"] == nil {
+
+ // Segwit softfork status should be found in blockchain
+ // info.
+ t.Fatal("Missing segwit status on blockchain info")
}
status := info.Bip9SoftForks["segwit"].Status
@@ -309,7 +313,8 @@ func ensureSegwitActive(r *rpctest.Harness, t *testing.T) {
}
if _, err := r.Client.Generate(100); err != nil {
- t.Fatalf("unable to generate blocks to activate segwit: %v", err)
+ t.Fatal("block generation to activate segwit failed;",
+ "err:", err.Error())
}
}
}
@@ -324,30 +329,33 @@ func testGetBlockTemplateSegwitActiveNoRule(r *rpctest.Harness, t *testing.T) {
}
_, err := r.Client.GetBlockTemplate(req)
-
if err == nil {
- t.Fatalf("Expected getblocktemplate to fail without 'segwit' rule")
+ t.Fatal("getblocktemplate must fail without 'segwit' rule")
}
// Expect: ErrRPCInvalidParameter with correct message
rpcErr, ok := err.(*btcjson.RPCError)
-
if !ok {
t.Fatalf("Expected an RPCError, but got: %v", err)
}
-
if rpcErr.Code != btcjson.ErrRPCInvalidParameter {
- t.Fatalf("Expected error code %d, but got: %d", btcjson.ErrRPCInvalidParameter, rpcErr.Code)
+ t.Fatal("Unexpected error code;",
+ "expected", btcjson.ErrRPCInvalidParameter,
+ "got", rpcErr.Code)
}
- expectedMessage := "Support for 'segwit' rule requires explicit client support"
-
+ expectedMessage := "Support for 'segwit' rule requires explicit " +
+ "client support"
if rpcErr.Message != expectedMessage {
- t.Fatalf("Expected error message '%s', but got: '%s'", expectedMessage, rpcErr.Message)
+ t.Fatal("Unexpected error message;",
+ "expected", expectedMessage,
+ "got", rpcErr.Message)
}
}
-func testGetBlockTemplateSegwitActiveWithRule(r *rpctest.Harness, t *testing.T) {
+func testGetBlockTemplateSegwitActiveWithRule(r *rpctest.Harness,
+ t *testing.T) {
+
// Guarantee SegWit is fully active before testing
ensureSegwitActive(r, t)
@@ -357,11 +365,10 @@ func testGetBlockTemplateSegwitActiveWithRule(r *rpctest.Harness, t *testing.T)
}
result, err := r.Client.GetBlockTemplate(req)
-
if err != nil {
- t.Fatalf("Expected getblocktemplate to succeed, got error: %v", err)
+ t.Fatal("Expected getblocktemplate to succeed;",
+ "got error:", err.Error())
}
-
if result == nil {
t.Fatal("Expected non-nil result")
}
@@ -373,7 +380,6 @@ func testGetBlockTemplateSegwitActiveWithRule(r *rpctest.Harness, t *testing.T)
break
}
}
-
if !hasSegwitRule {
t.Fatalf("Expected 'segwit' rule to be present in the response")
}
@@ -383,26 +389,25 @@ func testGetBlockTemplateResponseRules(r *rpctest.Harness, t *testing.T) {
// Guarantee SegWit is fully active before testing
ensureSegwitActive(r, t)
- // Call getblocktemplate with 'segwit' rule when segwit is active
+ // Call getblocktemplate with 'segwit' rule when segwit is active.
req := &btcjson.TemplateRequest{
Rules: []string{"segwit"},
}
result, err := r.Client.GetBlockTemplate(req)
-
if err != nil {
- t.Fatalf("Expected getblocktemplate to succeed, got error: %v", err)
+ t.Fatal("Expected getblocktemplate to succeed;",
+ "got error:", err.Error())
}
-
if result == nil {
t.Fatal("Expected non-nil result")
}
- // Verify blockTemplateResult includes "!segwit" in Rules when WitnessCommitment is non-nil
- // and "segwit" when WitnessCommitment is nil.
+ // Verify blockTemplateResult includes "!segwit" in Rules when
+ // WitnessCommitment is non-nil and "segwit" when WitnessCommitment is
+ // nil.
hasNotSegwit := false
hasSegwit := false
-
for _, rule := range result.Rules {
if rule == "!segwit" {
hasNotSegwit = true
@@ -410,15 +415,18 @@ func testGetBlockTemplateResponseRules(r *rpctest.Harness, t *testing.T) {
hasSegwit = true
}
}
+ hasWitnessCommitment := result.DefaultWitnessCommitment != ""
+ switch {
+ case hasWitnessCommitment && !hasNotSegwit:
+ // We expect Rules to contain '!segwit' when WitnessCommitment
+ // present.
+ t.Fatal("expected Rules to contain !segwit")
+
+ case !hasWitnessCommitment && !hasSegwit:
+ // We expect Rules to contain 'segwit' when WitnessCommitment is
+ // not present.
+ t.Fatal("expected Rules to contain segwit")
- if result.DefaultWitnessCommitment != "" {
- if !hasNotSegwit {
- t.Fatalf("Expected Rules to contain '!segwit' because WitnessCommitment is present")
- }
- } else {
- if !hasSegwit {
- t.Fatalf("Expected Rules to contain 'segwit' because WitnessCommitment is absent")
- }
}
}
diff --git a/rpcserver.go b/rpcserver.go
index b3faa90b..5ef652bc 100644
--- a/rpcserver.go
+++ b/rpcserver.go
@@ -20,6 +20,7 @@ import (
"net"
"net/http"
"os"
+ "slices"
"strconv"
"strings"
"sync"
@@ -1688,7 +1689,10 @@ func (state *gbtWorkState) updateBlockTemplate(s *rpcServer, useCoinbaseValue bo
// and returned to the caller.
//
// This function MUST be called with the state locked.
-func (state *gbtWorkState) blockTemplateResult(useCoinbaseValue bool, submitOld *bool, segwitActive bool) (*btcjson.GetBlockTemplateResult, error) {
+func (state *gbtWorkState) blockTemplateResult(useCoinbaseValue,
+ segwitActive bool,
+ submitOld *bool) (*btcjson.GetBlockTemplateResult, error) {
+
// Ensure the timestamps are still in valid range for the template.
// This should really only ever happen if the local clock is changed
// after the template is generated, but it's important to avoid serving
@@ -1843,7 +1847,10 @@ func (state *gbtWorkState) blockTemplateResult(useCoinbaseValue bool, submitOld
// has passed without finding a solution.
//
// See https://en.bitcoin.it/wiki/BIP_0022 for more details.
-func handleGetBlockTemplateLongPoll(s *rpcServer, longPollID string, useCoinbaseValue bool, closeChan <-chan struct{}, segwitActive bool) (interface{}, error) {
+func handleGetBlockTemplateLongPoll(s *rpcServer, longPollID string,
+ useCoinbaseValue, segwitActive bool,
+ closeChan <-chan struct{}) (interface{}, error) {
+
state := s.gbtWorkState
state.Lock()
// The state unlock is intentionally not deferred here since it needs to
@@ -1859,7 +1866,9 @@ func handleGetBlockTemplateLongPoll(s *rpcServer, longPollID string, useCoinbase
// the caller is invalid.
prevHash, lastGenerated, err := decodeTemplateID(longPollID)
if err != nil {
- result, err := state.blockTemplateResult(useCoinbaseValue, nil, segwitActive)
+ result, err := state.blockTemplateResult(
+ useCoinbaseValue, segwitActive, nil,
+ )
if err != nil {
state.Unlock()
return nil, err
@@ -1880,8 +1889,9 @@ func handleGetBlockTemplateLongPoll(s *rpcServer, longPollID string, useCoinbase
// old block template depending on whether or not a solution has
// already been found and added to the block chain.
submitOld := prevHash.IsEqual(prevTemplateHash)
- result, err := state.blockTemplateResult(useCoinbaseValue,
- &submitOld, segwitActive)
+ result, err := state.blockTemplateResult(
+ useCoinbaseValue, segwitActive, &submitOld,
+ )
if err != nil {
state.Unlock()
return nil, err
@@ -1921,7 +1931,9 @@ func handleGetBlockTemplateLongPoll(s *rpcServer, longPollID string, useCoinbase
// block template depending on whether or not a solution has already
// been found and added to the block chain.
submitOld := prevHash.IsEqual(&state.template.Block.Header.PrevBlock)
- result, err := state.blockTemplateResult(useCoinbaseValue, &submitOld, segwitActive)
+ result, err := state.blockTemplateResult(
+ useCoinbaseValue, segwitActive, &submitOld,
+ )
if err != nil {
return nil, err
}
@@ -1990,27 +2002,21 @@ func handleGetBlockTemplateRequest(s *rpcServer, request *btcjson.TemplateReques
}
}
- segwitState, err := s.cfg.Chain.ThresholdState(chaincfg.DeploymentSegwit)
+ segwitState, err := s.cfg.Chain.ThresholdState(
+ chaincfg.DeploymentSegwit,
+ )
if err != nil {
return nil, err
}
segwitActive := segwitState == blockchain.ThresholdActive
- hasSegwitRule := false
- if request != nil {
- for _, rule := range request.Rules {
- if rule == "segwit" {
- hasSegwitRule = true
- break
- }
- }
- }
-
+ hasSegwitRule := request != nil &&
+ slices.Contains(request.Rules, "segwit")
if segwitActive && !hasSegwitRule {
return nil, &btcjson.RPCError{
Code: btcjson.ErrRPCInvalidParameter,
- Message: "Support for 'segwit' rule requires explicit " +
- "client support",
+ Message: "Support for 'segwit' rule requires " +
+ "explicit client support",
}
}
@@ -2018,8 +2024,10 @@ func handleGetBlockTemplateRequest(s *rpcServer, request *btcjson.TemplateReques
// client to be notified when block template referenced by the ID should
// be replaced with a new one.
if request != nil && request.LongPollID != "" {
- return handleGetBlockTemplateLongPoll(s, request.LongPollID,
- useCoinbaseValue, closeChan, segwitActive)
+ return handleGetBlockTemplateLongPoll(
+ s, request.LongPollID, useCoinbaseValue, segwitActive,
+ closeChan,
+ )
}
// Protect concurrent access when updating block templates.
@@ -2036,7 +2044,9 @@ func handleGetBlockTemplateRequest(s *rpcServer, request *btcjson.TemplateReques
if err := state.updateBlockTemplate(s, useCoinbaseValue); err != nil {
return nil, err
}
- return state.blockTemplateResult(useCoinbaseValue, nil, segwitActive)
+ return state.blockTemplateResult(
+ useCoinbaseValue, segwitActive, nil,
+ )
}
// chainErrToGBTErrString converts an error returned from btcchain to a string
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Thanks for the review! Fixed the broken |
allocz
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Now all the tests are passing, but we still have some formatting things to fix. Tip: if you use vim, run git diff master >somefile and then open the diff on vim and set the color column to 80 chars and tab size to 8 spaces. Then you'll see the lines you edited that are longer than 80 columns.
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Thanks for the tip! I've addressed the formatting issues that were pointed out and pushed the updated changes. |
allocz
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This commit updates the getblocktemplate RPC to enforce the SegWit rules specified in BIP 145. Specifically, it ensures that: - Client requests are rejected with ErrRPCInvalidParameter if SegWit is active but the client does not explicitly support the 'segwit' rule. - The 'rules' array in the response conditionally includes '!segwit' if the generated block template contains transactions with witness data (indicating a witness commitment is required). - The 'rules' array includes 'segwit' (without the '!' prefix) when SegWit is active but the template does not contain any witness transactions. Additionally, integration tests have been added to verify that rule signaling and SegWit activation behave correctly during block template generation.
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|
|
||
| if info.Bip9SoftForks == nil || | ||
| info.Bip9SoftForks["segwit"] == nil { | ||
| t.Fatalf("segwit softfork status not found in" + |
There was a problem hiding this comment.
Empty line between info.Bip9SoftForks["segwit"] == nil { and t.Fatalf("segwit softfork status not found in" + would improve readability.
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Change Description
This PR addresses issue #1738 by enforcing BIP 145 SegWit rules within the
getblocktemplateRPC response.Specifically, this PR updates
rpcserver.goto ensure that:ErrRPCInvalidParameterif SegWit is active but the client does not explicitly include thesegwitrule in their request.rulesarray in the response conditionally includes!segwitif the generated block template contains transactions with witness data (indicating a witness commitment is required).rulesarray includessegwit(without the!prefix) when SegWit is active but the template does not contain any witness transactions.Steps to Test
go test -v -tags=rpctest -run=TestRpcServer ./integrationtestGetBlockTemplateSegwitActiveNoRule,testGetBlockTemplateSegwitActiveWithRule, andtestGetBlockTemplateResponseRulestests pass successfully.Pull Request Checklist
Testing
Code Style and Documentation