[feature] domain block wildcarding (#1178)

* for domain block lookups, lookup along subdomain parts

Signed-off-by: kim <grufwub@gmail.com>

* only lookup up to a max of 5 domain parts to prevent DOS, limit inserted domains to max of 5 subdomains

Signed-off-by: kim <grufwub@gmail.com>

* add test for domain block wildcarding

Signed-off-by: kim <grufwub@gmail.com>

* check cached status first, increase cached domain time

Signed-off-by: kim <grufwub@gmail.com>

* fix domain wildcard part building logic

Signed-off-by: kim <grufwub@gmail.com>

* create separate domain.BlockCache{} type to hold all domain blocks in memory

Signed-off-by: kim <grufwub@gmail.com>

* remove unused variable

Signed-off-by: kim <grufwub@gmail.com>

* add docs and test to domain block cache, check for domain == host in domain block getter funcs

Signed-off-by: kim <grufwub@gmail.com>

* add license text

Signed-off-by: kim <grufwub@gmail.com>

* check order in which we check primary cache

Signed-off-by: kim <grufwub@gmail.com>

* add better documentation of how domain block checking is performed

Signed-off-by: kim <grufwub@gmail.com>

* change

Signed-off-by: kim <grufwub@gmail.com>

Signed-off-by: kim <grufwub@gmail.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/internal/cache/domain/domain_test.go b/internal/cache/domain/domain_test.go
new file mode 100644
index 000000000..416ce5012
--- /dev/null
+++ b/internal/cache/domain/domain_test.go
@@ -0,0 +1,85 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package domain_test
+
+import (
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/superseriousbusiness/gotosocial/internal/cache/domain"
+)
+
+func TestBlockCache(t *testing.T) {
+	c := domain.New(100, time.Second)
+
+	blocks := []string{
+		"google.com",
+		"google.co.uk",
+		"pleroma.bad.host",
+	}
+
+	loader := func() ([]string, error) {
+		t.Log("load: returning blocked domains")
+		return blocks, nil
+	}
+
+	// Check a list of known blocked domains.
+	for _, domain := range []string{
+		"google.com",
+		"mail.google.com",
+		"google.co.uk",
+		"mail.google.co.uk",
+		"pleroma.bad.host",
+		"dev.pleroma.bad.host",
+	} {
+		t.Logf("checking domain is blocked: %s", domain)
+		if b, _ := c.IsBlocked(domain, loader); !b {
+			t.Errorf("domain should be blocked: %s", domain)
+		}
+	}
+
+	// Check a list of known unblocked domains.
+	for _, domain := range []string{
+		"askjeeves.com",
+		"ask-kim.co.uk",
+		"google.ie",
+		"mail.google.ie",
+		"gts.bad.host",
+		"mastodon.bad.host",
+	} {
+		t.Logf("checking domain isn't blocked: %s", domain)
+		if b, _ := c.IsBlocked(domain, loader); b {
+			t.Errorf("domain should not be blocked: %s", domain)
+		}
+	}
+
+	// Clear the cache
+	c.Clear()
+
+	knownErr := errors.New("known error")
+
+	// Check that reload is actually performed and returns our error
+	if _, err := c.IsBlocked("", func() ([]string, error) {
+		t.Log("load: returning known error")
+		return nil, knownErr
+	}); !errors.Is(err, knownErr) {
+		t.Errorf("is blocked did not return expected error: %v", err)
+	}
+}