From f41d5b98670c94dd6f3b3e1c5ed47f961d6b8a98 Mon Sep 17 00:00:00 2001
From: Eugene Burkov <e.burkov@adguard.com>
Date: Tue, 11 May 2021 20:33:02 +0300
Subject: [PATCH] Pull request: 3115 domain case

Merge in DNS/adguard-home from 3115-domain-case to master

Updates #3115.

Squashed commit of the following:

commit 02b6d27d862b3e3dc2a17220cec35f0f18e31fb3
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue May 11 19:56:06 2021 +0300

    all: fix typos

commit cdd1de64d5f79605b5fdcad5879204194856b083
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue May 11 19:37:37 2021 +0300

    dnsforward: fix disallowed domains case matching
---
 CHANGELOG.md                  | 6 ++++++
 internal/dnsforward/access.go | 2 +-
 internal/dnsforward/filter.go | 6 +++++-
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3b715104..42aef610 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,12 @@ and this project adheres to
 ## [v0.106.3] - 2021-05-17 (APPROX.)
 -->
 
+### Fixed
+
+- Disallowed domains are now case-insensitive ([#3115]).
+
+[#3115]: https://github.com/AdguardTeam/AdGuardHome/issues/3115
+
 
 
 ## [v0.106.2] - 2021-05-06
diff --git a/internal/dnsforward/access.go b/internal/dnsforward/access.go
index dba0015d..f27eb667 100644
--- a/internal/dnsforward/access.go
+++ b/internal/dnsforward/access.go
@@ -47,7 +47,7 @@ func newAccessCtx(allowedClients, disallowedClients, blockedHosts []string) (a *
 
 	b := &strings.Builder{}
 	for _, s := range blockedHosts {
-		aghstrings.WriteToBuilder(b, s, "\n")
+		aghstrings.WriteToBuilder(b, strings.ToLower(s), "\n")
 	}
 
 	listArray := []filterlist.RuleList{}
diff --git a/internal/dnsforward/filter.go b/internal/dnsforward/filter.go
index b0e3ff89..93a72a86 100644
--- a/internal/dnsforward/filter.go
+++ b/internal/dnsforward/filter.go
@@ -20,7 +20,11 @@ func (s *Server) beforeRequestHandler(_ *proxy.Proxy, d *proxy.DNSContext) (bool
 	}
 
 	if len(d.Req.Question) == 1 {
-		host := strings.TrimSuffix(d.Req.Question[0].Name, ".")
+		// It's lowercased here since this handler is called before any
+		// other one.
+		name := strings.ToLower(d.Req.Question[0].Name)
+		d.Req.Question[0].Name = name
+		host := strings.TrimSuffix(name, ".")
 		if s.access.IsBlockedDomain(host) {
 			log.Tracef("Domain %s is blocked by settings", host)
 			return false, nil