From bed74b38d985e48d1e8b4b8c132e97a8987e07ac Mon Sep 17 00:00:00 2001 From: Felix Lange Date: Thu, 25 Mar 2021 12:32:32 +0100 Subject: [PATCH] cmd/devp2p: fix comparison of TXT record value (#22572) * cmd/devp2p: fix comparison of TXT record value The AWS API returns quoted DNS strings, so we must encode the new value before comparing it against the existing record content. * cmd/devp2p: add test * cmd/devp2p: fix typo and rename val -> newValue --- cmd/devp2p/dns_route53.go | 35 +++++++++++++++++----------------- cmd/devp2p/dns_route53_test.go | 24 +++++++++++++++++++++++ 2 files changed, 42 insertions(+), 17 deletions(-) diff --git a/cmd/devp2p/dns_route53.go b/cmd/devp2p/dns_route53.go index 010913060a..2b6a30e60f 100644 --- a/cmd/devp2p/dns_route53.go +++ b/cmd/devp2p/dns_route53.go @@ -131,7 +131,7 @@ func (c *route53Client) deploy(name string, t *dnsdisc.Tree) error { } } - // wait for all change batches to propagate + // Wait for all change batches to propagate. for _, change := range changesToCheck { log.Info(fmt.Sprintf("Waiting for change request %s", *change.ChangeInfo.Id)) wreq := &route53.GetChangeInput{Id: change.ChangeInfo.Id} @@ -196,24 +196,29 @@ func (c *route53Client) computeChanges(name string, records map[string]string, e records = lrecords var changes []types.Change - for path, val := range records { + for path, newValue := range records { + prevRecords, exists := existing[path] + prevValue := strings.Join(prevRecords.values, "") + + // prevValue contains quoted strings, encode newValue to compare. + newValue = splitTXT(newValue) + + // Assign TTL. ttl := int64(rootTTL) if path != name { ttl = int64(treeNodeTTL) } - prevRecords, exists := existing[path] - prevValue := strings.Join(prevRecords.values, "") if !exists { // Entry is unknown, push a new one - log.Info(fmt.Sprintf("Creating %s = %q", path, val)) - changes = append(changes, newTXTChange("CREATE", path, ttl, splitTXT(val))) - } else if prevValue != val || prevRecords.ttl != ttl { + log.Info(fmt.Sprintf("Creating %s = %s", path, newValue)) + changes = append(changes, newTXTChange("CREATE", path, ttl, newValue)) + } else if prevValue != newValue || prevRecords.ttl != ttl { // Entry already exists, only change its content. - log.Info(fmt.Sprintf("Updating %s from %q to %q", path, prevValue, val)) - changes = append(changes, newTXTChange("UPSERT", path, ttl, splitTXT(val))) + log.Info(fmt.Sprintf("Updating %s from %s to %s", path, prevValue, newValue)) + changes = append(changes, newTXTChange("UPSERT", path, ttl, newValue)) } else { - log.Info(fmt.Sprintf("Skipping %s = %q", path, val)) + log.Debug(fmt.Sprintf("Skipping %s = %s", path, newValue)) } } @@ -288,21 +293,19 @@ func changeCount(ch types.Change) int { // collectRecords collects all TXT records below the given name. func (c *route53Client) collectRecords(name string) (map[string]recordSet, error) { - log.Info(fmt.Sprintf("Retrieving existing TXT records on %s (%s)", name, c.zoneID)) var req route53.ListResourceRecordSetsInput req.HostedZoneId = &c.zoneID existing := make(map[string]recordSet) - for { + for page := 0; ; page++ { + log.Info("Loading existing TXT records", "name", name, "zone", c.zoneID, "page", page) resp, err := c.api.ListResourceRecordSets(context.TODO(), &req) if err != nil { return existing, err } - for _, set := range resp.ResourceRecordSets { if !isSubdomain(*set.Name, name) || set.Type != types.RRTypeTxt { continue } - s := recordSet{ttl: *set.TTL} for _, rec := range set.ResourceRecords { s.values = append(s.values, *rec.Value) @@ -314,14 +317,12 @@ func (c *route53Client) collectRecords(name string) (map[string]recordSet, error if !resp.IsTruncated { break } - - // Set the cursor to the next batc. From the AWS docs: + // Set the cursor to the next batch. From the AWS docs: // // To display the next page of results, get the values of NextRecordName, // NextRecordType, and NextRecordIdentifier (if any) from the response. Then submit // another ListResourceRecordSets request, and specify those values for // StartRecordName, StartRecordType, and StartRecordIdentifier. - req.StartRecordIdentifier = resp.NextRecordIdentifier req.StartRecordName = resp.NextRecordName req.StartRecordType = resp.NextRecordType diff --git a/cmd/devp2p/dns_route53_test.go b/cmd/devp2p/dns_route53_test.go index 600c281a28..e6eb516e6b 100644 --- a/cmd/devp2p/dns_route53_test.go +++ b/cmd/devp2p/dns_route53_test.go @@ -162,5 +162,29 @@ func TestRoute53ChangeSort(t *testing.T) { } } +// This test checks that computeChanges compares the quoted value of the records correctly. +func TestRoute53NoChange(t *testing.T) { + // Existing record set. + testTree0 := map[string]recordSet{ + "n": {ttl: rootTTL, values: []string{ + `"enrtree-root:v1 e=JWXYDBPXYWG6FX3GMDIBFA6CJ4 l=C7HRFPF3BLGF3YR4DY5KX3SMBE seq=1 sig=o908WmNp7LibOfPsr4btQwatZJ5URBr2ZAuxvK4UWHlsB9sUOTJQaGAlLPVAhM__XJesCHxLISo94z5Z2a463gA"`, + }}, + "2xs2367yhaxjfglzhvawlqd4zy.n": {ttl: treeNodeTTL, values: []string{ + `"enr:-HW4QOFzoVLaFJnNhbgMoDXPnOvcdVuj7pDpqRvh6BRDO68aVi5ZcjB3vzQRZH2IcLBGHzo8uUN3snqmgTiE56CH3AMBgmlkgnY0iXNlY3AyNTZrMaECC2_24YYkYHEgdzxlSNKQEnHhuNAbNlMlWJxrJxbAFvA"`, + }}, + } + // New set. + testTree1 := map[string]string{ + "n": "enrtree-root:v1 e=JWXYDBPXYWG6FX3GMDIBFA6CJ4 l=C7HRFPF3BLGF3YR4DY5KX3SMBE seq=1 sig=o908WmNp7LibOfPsr4btQwatZJ5URBr2ZAuxvK4UWHlsB9sUOTJQaGAlLPVAhM__XJesCHxLISo94z5Z2a463gA", + "2XS2367YHAXJFGLZHVAWLQD4ZY.n": "enr:-HW4QOFzoVLaFJnNhbgMoDXPnOvcdVuj7pDpqRvh6BRDO68aVi5ZcjB3vzQRZH2IcLBGHzo8uUN3snqmgTiE56CH3AMBgmlkgnY0iXNlY3AyNTZrMaECC2_24YYkYHEgdzxlSNKQEnHhuNAbNlMlWJxrJxbAFvA", + } + + var client route53Client + changes := client.computeChanges("n", testTree1, testTree0) + if len(changes) > 0 { + t.Fatalf("wrong changes (got %d, want 0)", len(changes)) + } +} + func sp(s string) *string { return &s } func ip(i int64) *int64 { return &i }