nuke/lib/policy/expressions/environment_test.go
The Ninth 00fa939acf
Implement FCrDNS and other DNS features (#1308)
* Implement FCrDNS and other DNS features

* Redesign DNS cache and methods

* Fix DNS cache

* Rename regexSafe arg

* Alter verifyFCrDNS(addr) behaviour

* Remove unused dnsCache field from Server struct

* Upd expressions docs

* Update docs/docs/CHANGELOG.md

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

* refactor(dns): simplify FCrDNS logging

* docs: clarify verifyFCrDNS behavior

Add a note to the documentation for `verifyFCrDNS` to clarify that it returns true when no PTR records are found for the given IP address.

* fix(dns): Improve FCrDNS error handling and tests

The `VerifyFCrDNS` function previously ignored errors returned from reverse DNS lookups. This could lead to incorrect passes when a DNS failure (other than a simple 'not found') occurred. This change ensures that any error from a reverse lookup will cause the FCrDNS check to fail.

The test suite for FCrDNS has been updated to reflect this change. The mock DNS lookups now simulate both 'not found' errors and other generic DNS errors. The test cases have been updated to ensure that the function behaves correctly in both scenarios, resolving a situation where two test cases were effectively duplicates.

* docs: Update FCrDNS documentation and spelling

Corrected a typo in the `verifyFCrDNS` function documentation.

Additionally, updated the spelling exception list to include new terms and remove redundant entries.

* chore: update spelling

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

---------

Signed-off-by: Xe Iaso <me@xeiaso.net>
Co-authored-by: Xe Iaso <me@xeiaso.net>
2025-11-26 22:24:45 -05:00

752 lines
22 KiB
Go

package expressions
import (
"context"
"errors"
"net"
"strings"
"testing"
"github.com/TecharoHQ/anubis/internal/dns"
"github.com/TecharoHQ/anubis/lib/store/memory"
"github.com/google/cel-go/common/types"
"github.com/google/cel-go/common/types/ref"
)
// newTestDNS is a helper function to create a new Dns object with an in-memory cache for testing.
func newTestDNS(forwardTTL int, reverseTTL int) *dns.Dns {
ctx := context.Background()
memStore := memory.New(ctx)
cache := dns.NewDNSCache(forwardTTL, reverseTTL, memStore)
return dns.New(ctx, cache)
}
func TestBotEnvironment(t *testing.T) {
dnsObj := newTestDNS(300, 300)
env, err := BotEnvironment(dnsObj)
if err != nil {
t.Fatalf("failed to create bot environment: %v", err)
}
t.Run("missingHeader", func(t *testing.T) {
tests := []struct {
headers map[string]string
name string
expression string
description string
expected types.Bool
}{
{
name: "missing-header",
expression: `missingHeader(headers, "Missing-Header")`,
headers: map[string]string{
"User-Agent": "test-agent",
"Content-Type": "application/json",
},
expected: types.Bool(true),
description: "should return true when header is missing",
},
{
name: "existing-header",
expression: `missingHeader(headers, "User-Agent")`,
headers: map[string]string{
"User-Agent": "test-agent",
"Content-Type": "application/json",
},
expected: types.Bool(false),
description: "should return false when header exists",
},
{
name: "case-sensitive",
expression: `missingHeader(headers, "user-agent")`,
headers: map[string]string{
"User-Agent": "test-agent",
},
expected: types.Bool(true),
description: "should be case-sensitive (user-agent != User-Agent)",
},
{
name: "empty-headers",
expression: `missingHeader(headers, "Any-Header")`,
headers: map[string]string{},
expected: types.Bool(true),
description: "should return true for any header when map is empty",
},
{
name: "real-world-sec-ch-ua",
expression: `missingHeader(headers, "Sec-Ch-Ua")`,
headers: map[string]string{
"User-Agent": "curl/7.68.0",
"Accept": "*/*",
"Host": "example.com",
},
expected: types.Bool(true),
description: "should detect missing browser-specific headers from bots",
},
{
name: "browser-with-sec-ch-ua",
expression: `missingHeader(headers, "Sec-Ch-Ua")`,
headers: map[string]string{
"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36",
"Sec-Ch-Ua": `"Chrome"; v="91", "Not A Brand"; v="99"`,
"Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
},
expected: types.Bool(false),
description: "should return false when browser sends Sec-Ch-Ua header",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
prog, err := Compile(env, tt.expression)
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
result, _, err := prog.Eval(map[string]interface{}{
"headers": tt.headers,
})
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result != tt.expected {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
t.Run("function-compilation", func(t *testing.T) {
src := `missingHeader(headers, "Test-Header")`
_, err := Compile(env, src)
if err != nil {
t.Fatalf("failed to compile missingHeader expression: %v", err)
}
})
})
t.Run("segments", func(t *testing.T) {
for _, tt := range []struct {
name string
description string
expression string
path string
expected types.Bool
}{
{
name: "simple",
description: "/ should have one path segment",
expression: `size(segments(path)) == 1`,
path: "/",
expected: types.Bool(true),
},
{
name: "two segments without trailing slash",
description: "/user/foo should have two segments",
expression: `size(segments(path)) == 2`,
path: "/user/foo",
expected: types.Bool(true),
},
{
name: "at least two segments",
description: "/foo/bar/ should have at least two path segments",
expression: `size(segments(path)) >= 2`,
path: "/foo/bar/",
expected: types.Bool(true),
},
{
name: "at most two segments",
description: "/foo/bar/ does not have less than two path segments",
expression: `size(segments(path)) < 2`,
path: "/foo/bar/",
expected: types.Bool(false),
},
} {
t.Run(tt.name, func(t *testing.T) {
prog, err := Compile(env, tt.expression)
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
result, _, err := prog.Eval(map[string]interface{}{
"path": tt.path,
})
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result != tt.expected {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
t.Run("invalid", func(t *testing.T) {
for _, tt := range []struct {
env any
name string
description string
expression string
wantFailCompile bool
wantFailEval bool
}{
{
name: "segments of headers",
description: "headers are not a path list",
expression: `segments(headers)`,
env: map[string]any{
"headers": map[string]string{
"foo": "bar",
},
},
wantFailCompile: true,
},
{
name: "invalid path type",
description: "a path should be a sting",
expression: `size(segments(path)) != 0`,
env: map[string]any{
"path": 4,
},
wantFailEval: true,
},
{
name: "invalid path",
description: "a path should start with a leading slash",
expression: `size(segments(path)) != 0`,
env: map[string]any{
"path": "foo",
},
wantFailEval: true,
},
} {
t.Run(tt.name, func(t *testing.T) {
prog, err := Compile(env, tt.expression)
if err != nil {
if !tt.wantFailCompile {
t.Log(tt.description)
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
} else {
return
}
}
_, _, err = prog.Eval(tt.env)
if err == nil {
t.Log(tt.description)
t.Fatal("wanted an error but got none")
}
t.Log(err)
})
}
})
t.Run("function-compilation", func(t *testing.T) {
src := `size(segments(path)) <= 2`
_, err := Compile(env, src)
if err != nil {
t.Fatalf("failed to compile missingHeader expression: %v", err)
}
})
})
t.Run("regexSafe", func(t *testing.T) {
tests := []struct {
name string
expression string
expected types.String
description string
}{
{
name: "complex-test",
expression: `regexSafe("^(test1|test2|)[a-z]+$")`,
expected: types.String("\\^\\(test1\\|test2\\|\\)\\[a\\-z\\]\\+\\$"),
description: "should escape all reserved regex characters",
},
{
name: "backslash-test",
expression: `regexSafe("use \\\\ for special characters escaping\t, one/\"\\\"/for/cel and one/for/regex")`,
expected: types.String("use \\\\\\\\ for special characters escaping\t, one/\"\\\\\"/for/cel and one/for/regex"),
description: "should escape double-backslashes as double-double-backslashes and ignore cel escaping and forward slashes",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
prog, err := Compile(env, tt.expression)
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
result, _, err := prog.Eval(map[string]interface{}{})
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result != tt.expected {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
t.Run("function-compilation", func(t *testing.T) {
src := `regexSafe(".*")`
_, err := Compile(env, src)
if err != nil {
t.Fatalf("failed to compile regexSafe expression: %v", err)
}
})
})
t.Run("dnsFunctions", func(t *testing.T) {
originalDNSLookupAddr := dns.DNSLookupAddr
originalDNSLookupHost := dns.DNSLookupHost
defer func() {
dns.DNSLookupAddr = originalDNSLookupAddr
dns.DNSLookupHost = originalDNSLookupHost
}()
t.Run("reverseDNS", func(t *testing.T) {
tests := []struct {
name string
addr string
mockReturn []string
mockError error
expression string
expected ref.Val
description string
}{
{
name: "success",
addr: "8.8.8.8",
mockReturn: []string{"dns.google."},
expression: `reverseDNS("8.8.8.8")`,
expected: types.NewStringList(types.DefaultTypeAdapter, []string{"dns.google"}),
description: "should return domain names for an IP",
},
{
name: "not-found",
addr: "127.0.0.1",
mockReturn: []string{},
mockError: &net.DNSError{IsNotFound: true},
expression: `reverseDNS("127.0.0.1")`,
expected: types.NewStringList(types.DefaultTypeAdapter, []string{}),
description: "should return an empty list when not found",
},
{
name: "error",
addr: "error-addr",
mockError: errors.New("some dns error"),
expression: `reverseDNS("error-addr")`,
expected: types.NewStringList(types.DefaultTypeAdapter, []string{}),
description: "should return empty list on error",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
dns.DNSLookupAddr = func(addr string) ([]string, error) {
if addr == tt.addr {
return tt.mockReturn, tt.mockError
}
return nil, errors.New("unexpected address for reverse lookup")
}
prog, err := Compile(env, tt.expression)
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
result, _, err := prog.Eval(map[string]interface{}{})
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result.Equal(tt.expected) != types.True {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
})
t.Run("lookupHost", func(t *testing.T) {
tests := []struct {
name string
host string
mockReturn []string
mockError error
expression string
expected ref.Val
description string
}{
{
name: "success",
host: "dns.google",
mockReturn: []string{"8.8.8.8", "8.8.4.4"},
expression: `lookupHost("dns.google")`,
expected: types.NewStringList(types.DefaultTypeAdapter, []string{"8.8.8.8", "8.8.4.4"}),
description: "should return IPs for a domain name",
},
{
name: "not-found",
host: "nonexistent.domain.example.com",
mockReturn: []string{},
mockError: &net.DNSError{IsNotFound: true},
expression: `lookupHost("nonexistent.domain.example.com")`,
expected: types.NewStringList(types.DefaultTypeAdapter, []string{}),
description: "should return an empty list when not found",
},
{
name: "error",
host: "error-host",
mockError: errors.New("some dns error"),
expression: `lookupHost("error-host")`,
expected: types.NewStringList(types.DefaultTypeAdapter, []string{}),
description: "should return empty list on error",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
dns.DNSLookupHost = func(host string) ([]string, error) {
if host == tt.host {
return tt.mockReturn, tt.mockError
}
return nil, errors.New("unexpected host for forward lookup")
}
prog, err := Compile(env, tt.expression)
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
result, _, err := prog.Eval(map[string]interface{}{})
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result.Equal(tt.expected) != types.True {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
})
t.Run("verifyFCrDNS", func(t *testing.T) {
tests := []struct {
name string
addr string
reverseMockReturn []string
reverseMockError error
forwardMockReturn map[string][]string // name -> ips
forwardMockError map[string]error
expression string
expected types.Bool
description string
}{
{
name: "success",
addr: "8.8.8.8",
reverseMockReturn: []string{"dns.google."},
forwardMockReturn: map[string][]string{"dns.google": {"8.8.8.8", "8.8.4.4"}},
expression: `verifyFCrDNS("8.8.8.8")`,
expected: types.Bool(true),
description: "should return true for valid FCrDNS",
},
{
name: "failure",
addr: "1.2.3.4",
reverseMockReturn: []string{"spoofed.example.com."},
forwardMockReturn: map[string][]string{"spoofed.example.com": {"5.6.7.8"}},
expression: `verifyFCrDNS("1.2.3.4")`,
expected: types.Bool(false),
description: "should return false for invalid FCrDNS",
},
{
name: "reverse-lookup-fails",
addr: "1.1.1.1",
reverseMockError: errors.New("reverse lookup failed"),
expression: `verifyFCrDNS("1.1.1.1")`,
expected: types.Bool(false),
description: "should return false if reverse lookup fails",
},
{
name: "success-with-pattern",
addr: "8.8.8.8",
reverseMockReturn: []string{"dns.google."},
forwardMockReturn: map[string][]string{"dns.google": {"8.8.8.8"}},
expression: `verifyFCrDNS("8.8.8.8", "dns.google")`,
expected: types.Bool(true),
description: "should return true for valid FCrDNS with matching pattern",
},
{
name: "failure-with-pattern",
addr: "8.8.8.8",
reverseMockReturn: []string{"dns.google."},
forwardMockReturn: map[string][]string{"dns.google": {"8.8.8.8"}},
expression: `verifyFCrDNS("8.8.8.8", "wrong.pattern")`,
expected: types.Bool(false),
description: "should return false for FCrDNS with non-matching pattern",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
dns.DNSLookupAddr = func(addr string) ([]string, error) {
if addr == tt.addr {
return tt.reverseMockReturn, tt.reverseMockError
}
return nil, errors.New("unexpected address for reverse lookup")
}
dns.DNSLookupHost = func(host string) ([]string, error) {
host = strings.TrimSuffix(host, ".")
if ips, ok := tt.forwardMockReturn[host]; ok {
return ips, nil
}
if err, ok := tt.forwardMockError[host]; ok {
return nil, err
}
return nil, &net.DNSError{IsNotFound: true}
}
prog, err := Compile(env, tt.expression)
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
result, _, err := prog.Eval(map[string]interface{}{})
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result.Equal(tt.expected) != types.True {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
})
t.Run("arpaReverseIP", func(t *testing.T) {
tests := []struct {
name string
expression string
expected types.String
description string
evalError bool
}{
{
name: "ipv4",
expression: `arpaReverseIP("1.2.3.4")`,
expected: types.String("4.3.2.1"),
description: "should correctly reverse an IPv4 address",
},
{
name: "ipv6",
expression: `arpaReverseIP("2001:db8::1")`,
expected: types.String("1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2"),
description: "should correctly reverse an IPv6 address",
},
{
name: "ipv6-full",
expression: `arpaReverseIP("2001:0db8:85a3:0000:0000:8a2e:0370:7334")`,
expected: types.String("4.3.3.7.0.7.3.0.e.2.a.8.0.0.0.0.0.0.0.0.3.a.5.8.8.b.d.0.1.0.0.2"),
description: "should correctly reverse a fully expanded IPv6 address",
},
{
name: "ipv6-loopback",
expression: `arpaReverseIP("::1")`,
expected: types.String("1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0"),
description: "should correctly reverse the IPv6 loopback address",
},
{
name: "invalid-ip",
expression: `arpaReverseIP("not-an-ip")`,
evalError: true,
description: "should error on an invalid IP",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
prog, err := Compile(env, tt.expression)
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
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)
}
return
}
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result.Equal(tt.expected) != types.True {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
})
})
}
func TestThresholdEnvironment(t *testing.T) {
env, err := ThresholdEnvironment()
if err != nil {
t.Fatalf("failed to create threshold environment: %v", err)
}
tests := []struct {
variables map[string]interface{}
name string
expression string
description string
expected types.Bool
shouldCompile bool
}{
{
name: "weight-variable-available",
expression: `weight > 100`,
variables: map[string]interface{}{"weight": 150},
expected: types.Bool(true),
description: "should support weight variable in expressions",
shouldCompile: true,
},
{
name: "weight-variable-false-case",
expression: `weight > 100`,
variables: map[string]interface{}{"weight": 50},
expected: types.Bool(false),
description: "should correctly evaluate weight comparisons",
shouldCompile: true,
},
{
name: "missingHeader-not-available",
expression: `missingHeader(headers, "Test")`,
variables: map[string]interface{}{},
expected: types.Bool(false), // not used
description: "should not have missingHeader function available",
shouldCompile: false,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
prog, err := Compile(env, tt.expression)
if !tt.shouldCompile {
if err == nil {
t.Fatalf("%s: expected compilation to fail but it succeeded", tt.description)
}
return // Test passed - compilation failed as expected
}
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
result, _, err := prog.Eval(tt.variables)
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result != tt.expected {
t.Errorf("%s: expected %v, got %v", tt.description, tt.expected, result)
}
})
}
}
func TestNewEnvironment(t *testing.T) {
env, err := New()
if err != nil {
t.Fatalf("failed to create new environment: %v", err)
}
tests := []struct {
name string
expression string
variables map[string]interface{}
expectBool *bool // nil if we just want to test compilation or non-bool result
description string
shouldCompile bool
}{
{
name: "randInt-function-compilation",
expression: `randInt(10)`,
variables: map[string]interface{}{},
expectBool: nil, // Don't check result, just compilation
description: "should compile randInt function",
shouldCompile: true,
},
{
name: "randInt-range-validation",
expression: `randInt(10) >= 0 && randInt(10) < 10`,
variables: map[string]interface{}{},
expectBool: boolPtr(true),
description: "should return values in correct range",
shouldCompile: true,
},
{
name: "strings-extension-size",
expression: `"hello".size() == 5`,
variables: map[string]interface{}{},
expectBool: boolPtr(true),
description: "should support string extension functions",
shouldCompile: true,
},
{
name: "strings-extension-contains",
expression: `"hello world".contains("world")`,
variables: map[string]interface{}{},
expectBool: boolPtr(true),
description: "should support string contains function",
shouldCompile: true,
},
{
name: "strings-extension-startsWith",
expression: `"hello world".startsWith("hello")`,
variables: map[string]interface{}{},
expectBool: boolPtr(true),
description: "should support string startsWith function",
shouldCompile: true,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
prog, err := Compile(env, tt.expression)
if !tt.shouldCompile {
if err == nil {
t.Fatalf("%s: expected compilation to fail but it succeeded", tt.description)
}
return // Test passed - compilation failed as expected
}
if err != nil {
t.Fatalf("failed to compile expression %q: %v", tt.expression, err)
}
// If we only want to test compilation, skip evaluation
if tt.expectBool == nil {
return
}
result, _, err := prog.Eval(tt.variables)
if err != nil {
t.Fatalf("failed to evaluate expression %q: %v", tt.expression, err)
}
if result != types.Bool(*tt.expectBool) {
t.Errorf("%s: expected %v, got %v", tt.description, *tt.expectBool, result)
}
})
}
}
// Helper function to create bool pointers
func boolPtr(b bool) *bool {
return &b
}