docs(admin/policy): document ReadWritePaths for logging to files

The default Anubis systemd configuration is very restrictive in
order to prevent any possible compromise of Anubis to be useful
by threat actors. As such, it assumes all logs will be pushed to
the system journal. Some administrators do not want Anubis' logs
to be pushed to the system journal and want Anubis to log to a
file instead.

This change documents how to set up ReadWritePaths in the Anubis
systemd configuration such that Anubis can lot to a file as
administrators expect.

Closes: #1468
Signed-off-by: Xe Iaso <me@xeiaso.net>

cmd/anubis/main.go

@@ -418,8 +418,8 @@ func main() {
 
 	var redirectDomainsList []string
 	if *redirectDomains != "" {
-		domains := strings.SplitSeq(*redirectDomains, ",")
-		for domain := range domains {
+		domains := strings.Split(*redirectDomains, ",")
+		for _, domain := range domains {
 			_, err = url.Parse(domain)
 			if err != nil {
 				log.Fatalf("cannot parse redirect-domain %q: %s", domain, err.Error())

cmd/robots2policy/main.go

@@ -10,7 +10,6 @@ import (
 	"net/http"
 	"os"
 	"regexp"
-	"slices"
 	"strings"
 
 	"github.com/TecharoHQ/anubis/lib/config"
@@ -211,8 +210,11 @@ func parseRobotsTxt(input io.Reader) ([]RobotsRule, error) {
 
 	// Mark blacklisted user agents (those with "Disallow: /")
 	for i := range rules {
-		if slices.Contains(rules[i].Disallows, "/") {
-			rules[i].IsBlacklist = true
+		for _, disallow := range rules[i].Disallows {
+			if disallow == "/" {
+				rules[i].IsBlacklist = true
+				break
+			}
 		}
 	}
 

cmd/robots2policy/robots2policy_test.go

@@ -158,8 +158,8 @@ func TestDataFileConversion(t *testing.T) {
 			}
 
 			if strings.ToLower(*outputFormat) == "yaml" {
-				var actualData []any
-				var expectedData []any
+				var actualData []interface{}
+				var expectedData []interface{}
 
 				err = yaml.Unmarshal(actualOutput, &actualData)
 				if err != nil {
@@ -178,8 +178,8 @@ func TestDataFileConversion(t *testing.T) {
 					t.Errorf("Output mismatch for %s\nExpected:\n%s\n\nActual:\n%s", tc.name, expectedStr, actualStr)
 				}
 			} else {
-				var actualData []any
-				var expectedData []any
+				var actualData []interface{}
+				var expectedData []interface{}
 
 				err = json.Unmarshal(actualOutput, &actualData)
 				if err != nil {
@@ -419,6 +419,6 @@ Disallow: /`
 
 // compareData performs a deep comparison of two data structures,
 // ignoring differences that are semantically equivalent in YAML/JSON
-func compareData(actual, expected any) bool {
+func compareData(actual, expected interface{}) bool {
 	return reflect.DeepEqual(actual, expected)
 }

docs/docs/admin/policies.mdx

@@ -393,6 +393,32 @@ logging:
 
 When files are rotated out, the old files will be named after the rotation timestamp in [RFC 3339 format](https://www.rfc-editor.org/rfc/rfc3339).
 
+:::note
+
+If you are running Anubis in systemd via a native package, the default systemd unit settings are very restrictive and will forbid writing to folders in `/var/log`. In order to fix this, please make a [drop-in unit](https://www.flatcar.org/docs/latest/setup/systemd/drop-in-units/) like the following:
+
+```text
+# /etc/systemd/anubis@instance-name.service.d/50-var-log-readwrite.conf
+[Service]
+ReadWritePaths=/run /var/log/anubis
+```
+
+Once you write this to the correct place, reload the systemd configuration:
+
+```text
+sudo systemctl daemon-reload
+```
+
+And then restart Anubis:
+
+```text
+sudo systemctl restart anubis@instance-name
+```
+
+You may be required to make drop-ins for each Anubis instance depending on the facts and circumstances of your deployment.
+
+:::
+
 ### `stdio` sink
 
 By default, Anubis logs everything to the standard error stream of its process. This requires no configuration:

internal/glob/glob.go

@@ -36,7 +36,7 @@ func Glob(pattern, subj string) bool {
 	end := len(parts) - 1
 
 	// Go over the leading parts and ensure they match.
-	for i := range end {
+	for i := 0; i < end; i++ {
 		idx := strings.Index(subj, parts[i])
 
 		switch i {

internal/hash_bench_test.go

@@ -184,7 +184,7 @@ func TestHashCollisions(t *testing.T) {
 	for _, prefix := range prefixes {
 		for _, suffix := range suffixes {
 			for _, variation := range variations {
-				for i := range 100 {
+				for i := 0; i < 100; i++ {
 					input := fmt.Sprintf("%s%s%s-%d", prefix, suffix, variation, i)
 					hash := XXHash64sum(input)
 					if existing, exists := xxhashHashes[hash]; exists {
@@ -211,7 +211,7 @@ func TestHashCollisions(t *testing.T) {
 
 	seqCount := 0
 	for _, pattern := range patterns {
-		for i := range 10000 {
+		for i := 0; i < 10000; i++ {
 			input := fmt.Sprintf(pattern, i)
 			hash := XXHash64sum(input)
 			if existing, exists := xxhashHashes[hash]; exists {

internal/honeypot/naive/naive.go

@@ -120,7 +120,7 @@ func (i *Impl) makeAffirmations() []string {
 	count := rand.IntN(5) + 1
 
 	var result []string
-	for range count {
+	for j := 0; j < count; j++ {
 		result = append(result, i.affirmation.Spin())
 	}
 
@@ -131,7 +131,7 @@ func (i *Impl) makeSpins() []string {
 	count := rand.IntN(5) + 1
 
 	var result []string
-	for range count {
+	for j := 0; j < count; j++ {
 		result = append(result, i.body.Spin())
 	}
 

internal/listor.go

@@ -16,7 +16,7 @@ func (lo *ListOr[T]) UnmarshalJSON(data []byte) error {
 
 	// Check if first non-whitespace character is '['
 	firstChar := data[0]
-	for i := range data {
+	for i := 0; i < len(data); i++ {
 		if data[i] != ' ' && data[i] != '\t' && data[i] != '\n' && data[i] != '\r' {
 			firstChar = data[i]
 			break
@@ -36,4 +36,4 @@ func (lo *ListOr[T]) UnmarshalJSON(data []byte) error {
 	}
 
 	return nil
-}
+}

internal/ogtags/mem_test.go

@@ -95,7 +95,7 @@ func TestMemoryUsage(t *testing.T) {
 
 	// Run getTarget many times
 	u, _ := url.Parse("/path/to/resource?query=1&foo=bar&baz=qux")
-	for range 10000 {
+	for i := 0; i < 10000; i++ {
 		_ = cache.getTarget(u)
 	}
 
@@ -129,7 +129,7 @@ func TestMemoryUsage(t *testing.T) {
 	runtime.GC()
 	runtime.ReadMemStats(&m1)
 
-	for range 1000 {
+	for i := 0; i < 1000; i++ {
 		_ = cache.extractOGTags(doc)
 	}
 

internal/ogtags/ogtags_fuzz_test.go

@@ -3,7 +3,6 @@ package ogtags
 import (
 	"context"
 	"net/url"
-	"slices"
 	"strings"
 	"testing"
 	"unicode/utf8"
@@ -79,7 +78,7 @@ func FuzzGetTarget(f *testing.F) {
 		}
 
 		// Ensure no memory corruption by calling multiple times
-		for range 3 {
+		for i := 0; i < 3; i++ {
 			result2 := cache.getTarget(u)
 			if result != result2 {
 				t.Errorf("getTarget not deterministic: %q != %q", result, result2)
@@ -149,8 +148,11 @@ func FuzzExtractOGTags(f *testing.F) {
 				}
 			}
 			if !approved {
-				if slices.Contains(cache.approvedTags, property) {
-					approved = true
+				for _, tag := range cache.approvedTags {
+					if property == tag {
+						approved = true
+						break
+					}
 				}
 			}
 			if !approved {
@@ -258,8 +260,11 @@ func FuzzExtractMetaTagInfo(f *testing.F) {
 				}
 			}
 			if !approved {
-				if slices.Contains(cache.approvedTags, property) {
-					approved = true
+				for _, tag := range cache.approvedTags {
+					if property == tag {
+						approved = true
+						break
+					}
 				}
 			}
 			if !approved {

internal/ogtags/parse.go

@@ -1,7 +1,6 @@
 package ogtags
 
 import (
-	"slices"
 	"strings"
 
 	"golang.org/x/net/html"
@@ -66,8 +65,10 @@ func (c *OGTagCache) extractMetaTagInfo(n *html.Node) (property, content string)
 	}
 
 	// Check exact matches
-	if slices.Contains(c.approvedTags, propertyKey) {
-		return propertyKey, content
+	for _, tag := range c.approvedTags {
+		if propertyKey == tag {
+			return propertyKey, content
+		}
 	}
 
 	return "", content

internal/test/playwright_test.go

@@ -270,7 +270,7 @@ func TestPlaywrightBrowser(t *testing.T) {
 
 				var performedAction action
 				var err error
-				for i := range 5 {
+				for i := 0; i < 5; i++ {
 					performedAction, err = executeTestCase(t, tc, typ, anubisURL)
 					if performedAction == tc.action {
 						break

lib/anubis.go

@@ -81,11 +81,11 @@ type Server struct {
 func (s *Server) getTokenKeyfunc() jwt.Keyfunc {
 	// return ED25519 key if HS512 is not set
 	if len(s.hs512Secret) == 0 {
-		return func(token *jwt.Token) (any, error) {
+		return func(token *jwt.Token) (interface{}, error) {
 			return s.ed25519Priv.Public().(ed25519.PublicKey), nil
 		}
 	} else {
-		return func(token *jwt.Token) (any, error) {
+		return func(token *jwt.Token) (interface{}, error) {
 			return s.hs512Secret, nil
 		}
 	}

lib/anubis_test.go

@@ -38,8 +38,8 @@ func NewTLogWriter(t *testing.T) io.Writer {
 
 // Write splits input on newlines and logs each line separately.
 func (w *TLogWriter) Write(p []byte) (n int, err error) {
-	lines := strings.SplitSeq(string(p), "\n")
-	for line := range lines {
+	lines := strings.Split(string(p), "\n")
+	for _, line := range lines {
 		if line != "" {
 			w.t.Log(line)
 		}

lib/config/config.go

@@ -228,8 +228,8 @@ type ImportStatement struct {
 }
 
 func (is *ImportStatement) open() (fs.File, error) {
-	if after, ok := strings.CutPrefix(is.Import, "(data)/"); ok {
-		fname := after
+	if strings.HasPrefix(is.Import, "(data)/") {
+		fname := strings.TrimPrefix(is.Import, "(data)/")
 		fin, err := data.BotPolicies.Open(fname)
 		return fin, err
 	}
@@ -325,7 +325,7 @@ func (sc StatusCodes) Valid() error {
 }
 
 type fileConfig struct {
-	OpenGraph   openGraphFileConfig `json:"openGraph"`
+	OpenGraph   openGraphFileConfig `json:"openGraph,omitempty"`
 	Impressum   *Impressum          `json:"impressum,omitempty"`
 	Store       *Store              `json:"store"`
 	Bots        []BotOrImport       `json:"bots"`

lib/config/config_test.go

@@ -188,6 +188,7 @@ func TestBotValid(t *testing.T) {
 	}
 
 	for _, cs := range tests {
+		cs := cs
 		t.Run(cs.name, func(t *testing.T) {
 			err := cs.bot.Valid()
 			if err == nil && cs.err == nil {
@@ -215,6 +216,7 @@ func TestConfigValidKnownGood(t *testing.T) {
 	}
 
 	for _, st := range finfos {
+		st := st
 		t.Run(st.Name(), func(t *testing.T) {
 			fin, err := os.Open(filepath.Join("testdata", "good", st.Name()))
 			if err != nil {
@@ -301,6 +303,7 @@ func TestConfigValidBad(t *testing.T) {
 	}
 
 	for _, st := range finfos {
+		st := st
 		t.Run(st.Name(), func(t *testing.T) {
 			fin, err := os.Open(filepath.Join("testdata", "bad", st.Name()))
 			if err != nil {

lib/config_test.go

@@ -24,6 +24,7 @@ func TestBadConfigs(t *testing.T) {
 	}
 
 	for _, st := range finfos {
+		st := st
 		t.Run(st.Name(), func(t *testing.T) {
 			if _, err := LoadPoliciesOrDefault(t.Context(), filepath.Join("config", "testdata", "bad", st.Name()), anubis.DefaultDifficulty, "info"); err == nil {
 				t.Fatal(err)
@@ -41,6 +42,7 @@ func TestGoodConfigs(t *testing.T) {
 	}
 
 	for _, st := range finfos {
+		st := st
 		t.Run(st.Name(), func(t *testing.T) {
 			t.Run("with-thoth", func(t *testing.T) {
 				ctx := thothmock.WithMockThoth(t)

lib/http.go

@@ -182,7 +182,10 @@ func makeCode(err error) string {
 	enc := base64.StdEncoding.EncodeToString(buf.Bytes())
 	var builder strings.Builder
 	for i := 0; i < len(enc); i += width {
-		end := min(i+width, len(enc))
+		end := i + width
+		if end > len(enc) {
+			end = len(enc)
+		}
 		builder.WriteString(enc[i:end])
 		builder.WriteByte('\n')
 	}

lib/policy/expressions/environment_test.go

@@ -103,7 +103,7 @@ func TestBotEnvironment(t *testing.T) {
 					t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
 				}
 
-				result, _, err := prog.Eval(map[string]any{
+				result, _, err := prog.Eval(map[string]interface{}{
 					"headers": tt.headers,
 				})
 				if err != nil {
@@ -168,7 +168,7 @@ func TestBotEnvironment(t *testing.T) {
 					t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
 				}
 
-				result, _, err := prog.Eval(map[string]any{
+				result, _, err := prog.Eval(map[string]interface{}{
 					"path": tt.path,
 				})
 				if err != nil {
@@ -280,7 +280,7 @@ func TestBotEnvironment(t *testing.T) {
 					t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
 				}
 
-				result, _, err := prog.Eval(map[string]any{})
+				result, _, err := prog.Eval(map[string]interface{}{})
 				if err != nil {
 					t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
 				}
@@ -359,7 +359,7 @@ func TestBotEnvironment(t *testing.T) {
 						t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
 					}
 
-					result, _, err := prog.Eval(map[string]any{})
+					result, _, err := prog.Eval(map[string]interface{}{})
 					if err != nil {
 						t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
 					}
@@ -421,7 +421,7 @@ func TestBotEnvironment(t *testing.T) {
 						t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
 					}
 
-					result, _, err := prog.Eval(map[string]any{})
+					result, _, err := prog.Eval(map[string]interface{}{})
 					if err != nil {
 						t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
 					}
@@ -514,7 +514,7 @@ func TestBotEnvironment(t *testing.T) {
 						t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
 					}
 
-					result, _, err := prog.Eval(map[string]any{})
+					result, _, err := prog.Eval(map[string]interface{}{})
 					if err != nil {
 						t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
 					}
@@ -572,7 +572,7 @@ func TestBotEnvironment(t *testing.T) {
 						t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
 					}
 
-					result, _, err := prog.Eval(map[string]any{})
+					result, _, err := prog.Eval(map[string]interface{}{})
 					if tt.evalError {
 						if err == nil {
 							t.Errorf("%s: expected an evaluation error, but got none", tt.description)
@@ -598,7 +598,7 @@ func TestThresholdEnvironment(t *testing.T) {
 	}
 
 	tests := []struct {
-		variables     map[string]any
+		variables     map[string]interface{}
 		name          string
 		expression    string
 		description   string
@@ -608,7 +608,7 @@ func TestThresholdEnvironment(t *testing.T) {
 		{
 			name:          "weight-variable-available",
 			expression:    `weight > 100`,
-			variables:     map[string]any{"weight": 150},
+			variables:     map[string]interface{}{"weight": 150},
 			expected:      types.Bool(true),
 			description:   "should support weight variable in expressions",
 			shouldCompile: true,
@@ -616,7 +616,7 @@ func TestThresholdEnvironment(t *testing.T) {
 		{
 			name:          "weight-variable-false-case",
 			expression:    `weight > 100`,
-			variables:     map[string]any{"weight": 50},
+			variables:     map[string]interface{}{"weight": 50},
 			expected:      types.Bool(false),
 			description:   "should correctly evaluate weight comparisons",
 			shouldCompile: true,
@@ -624,7 +624,7 @@ func TestThresholdEnvironment(t *testing.T) {
 		{
 			name:          "missingHeader-not-available",
 			expression:    `missingHeader(headers, "Test")`,
-			variables:     map[string]any{},
+			variables:     map[string]interface{}{},
 			expected:      types.Bool(false), // not used
 			description:   "should not have missingHeader function available",
 			shouldCompile: false,
@@ -667,7 +667,7 @@ func TestNewEnvironment(t *testing.T) {
 	tests := []struct {
 		name          string
 		expression    string
-		variables     map[string]any
+		variables     map[string]interface{}
 		expectBool    *bool // nil if we just want to test compilation or non-bool result
 		description   string
 		shouldCompile bool
@@ -675,7 +675,7 @@ func TestNewEnvironment(t *testing.T) {
 		{
 			name:          "randInt-function-compilation",
 			expression:    `randInt(10)`,
-			variables:     map[string]any{},
+			variables:     map[string]interface{}{},
 			expectBool:    nil, // Don't check result, just compilation
 			description:   "should compile randInt function",
 			shouldCompile: true,
@@ -683,7 +683,7 @@ func TestNewEnvironment(t *testing.T) {
 		{
 			name:          "randInt-range-validation",
 			expression:    `randInt(10) >= 0 && randInt(10) < 10`,
-			variables:     map[string]any{},
+			variables:     map[string]interface{}{},
 			expectBool:    boolPtr(true),
 			description:   "should return values in correct range",
 			shouldCompile: true,
@@ -691,7 +691,7 @@ func TestNewEnvironment(t *testing.T) {
 		{
 			name:          "strings-extension-size",
 			expression:    `"hello".size() == 5`,
-			variables:     map[string]any{},
+			variables:     map[string]interface{}{},
 			expectBool:    boolPtr(true),
 			description:   "should support string extension functions",
 			shouldCompile: true,
@@ -699,7 +699,7 @@ func TestNewEnvironment(t *testing.T) {
 		{
 			name:          "strings-extension-contains",
 			expression:    `"hello world".contains("world")`,
-			variables:     map[string]any{},
+			variables:     map[string]interface{}{},
 			expectBool:    boolPtr(true),
 			description:   "should support string contains function",
 			shouldCompile: true,
@@ -707,7 +707,7 @@ func TestNewEnvironment(t *testing.T) {
 		{
 			name:          "strings-extension-startsWith",
 			expression:    `"hello world".startsWith("hello")`,
-			variables:     map[string]any{},
+			variables:     map[string]interface{}{},
 			expectBool:    boolPtr(true),
 			description:   "should support string startsWith function",
 			shouldCompile: true,

lib/policy/policy_test.go

@@ -32,6 +32,7 @@ func TestGoodConfigs(t *testing.T) {
 	}
 
 	for _, st := range finfos {
+		st := st
 		t.Run(st.Name(), func(t *testing.T) {
 			t.Run("with-thoth", func(t *testing.T) {
 				fin, err := os.Open(filepath.Join("..", "config", "testdata", "good", st.Name()))
@@ -70,6 +71,7 @@ func TestBadConfigs(t *testing.T) {
 	}
 
 	for _, st := range finfos {
+		st := st
 		t.Run(st.Name(), func(t *testing.T) {
 			fin, err := os.Open(filepath.Join("..", "config", "testdata", "bad", st.Name()))
 			if err != nil {

lib/store/s3api/s3api_test.go

@@ -6,7 +6,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"maps"
 	"sync"
 	"testing"
 	"time"
@@ -37,7 +36,9 @@ func (m *mockS3) PutObject(ctx context.Context, in *s3.PutObjectInput, _ ...func
 	m.data[aws.ToString(in.Key)] = bytes.Clone(b)
 	if in.Metadata != nil {
 		m.meta[aws.ToString(in.Key)] = map[string]string{}
-		maps.Copy(m.meta[aws.ToString(in.Key)], in.Metadata)
+		for k, v := range in.Metadata {
+			m.meta[aws.ToString(in.Key)][k] = v
+		}
 	}
 	m.bucket = aws.ToString(in.Bucket)
 	return &s3.PutObjectOutput{}, nil

lib/store/valkey/factory.go

@@ -103,7 +103,7 @@ func (s Sentinel) Valid() error {
 // redisClient is satisfied by *valkey.Client and *valkey.ClusterClient.
 type redisClient interface {
 	Get(ctx context.Context, key string) *valkey.StringCmd
-	Set(ctx context.Context, key string, value any, expiration time.Duration) *valkey.StatusCmd
+	Set(ctx context.Context, key string, value interface{}, expiration time.Duration) *valkey.StatusCmd
 	Del(ctx context.Context, keys ...string) *valkey.IntCmd
 	Ping(ctx context.Context) *valkey.StatusCmd
 }

lib/thoth/auth.go

@@ -11,8 +11,8 @@ func authUnaryClientInterceptor(token string) grpc.UnaryClientInterceptor {
 	return func(
 		ctx context.Context,
 		method string,
-		req any,
-		reply any,
+		req interface{},
+		reply interface{},
 		cc *grpc.ClientConn,
 		invoker grpc.UnaryInvoker,
 		opts ...grpc.CallOption,