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consul/agent/xds/rbac_test.go

901 lines
24 KiB

package xds
import (
"fmt"
"path/filepath"
"sort"
"testing"
envoy_rbac_v3 "github.com/envoyproxy/go-control-plane/envoy/config/rbac/v3"
envoy_matcher_v3 "github.com/envoyproxy/go-control-plane/envoy/type/matcher/v3"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"github.com/hashicorp/consul/agent/structs"
)
func TestRemoveIntentionPrecedence(t *testing.T) {
testIntention := func(t *testing.T, src, dst string, action structs.IntentionAction) *structs.Intention {
t.Helper()
ixn := structs.TestIntention(t)
ixn.SourceName = src
ixn.DestinationName = dst
ixn.Action = action
//nolint:staticcheck
ixn.UpdatePrecedence()
return ixn
}
testSourceIntention := func(src string, action structs.IntentionAction) *structs.Intention {
return testIntention(t, src, "api", action)
}
testSourcePermIntention := func(src string, perms ...*structs.IntentionPermission) *structs.Intention {
ixn := testIntention(t, src, "api", "")
ixn.Permissions = perms
return ixn
}
sorted := func(ixns ...*structs.Intention) structs.Intentions {
sort.SliceStable(ixns, func(i, j int) bool {
return ixns[j].Precedence < ixns[i].Precedence
})
return structs.Intentions(ixns)
}
var (
nameWild = structs.NewServiceName("*", nil)
nameWeb = structs.NewServiceName("web", nil)
permSlashPrefix = &structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
}
permDenySlashPrefix = &structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
}
xdsPermSlashPrefix = &envoy_rbac_v3.Permission{
Rule: &envoy_rbac_v3.Permission_UrlPath{
UrlPath: &envoy_matcher_v3.PathMatcher{
Rule: &envoy_matcher_v3.PathMatcher_Path{
Path: &envoy_matcher_v3.StringMatcher{
MatchPattern: &envoy_matcher_v3.StringMatcher_Prefix{
Prefix: "/",
},
},
},
},
},
}
)
// NOTE: these default=(allow|deny) wild=(allow|deny) path=(allow|deny)
// tests below are meant to verify some of the behaviors work as expected
// when the default acl mode changes for the system
tests := map[string]struct {
intentionDefaultAllow bool
http bool
intentions structs.Intentions
expect []*rbacIntention
}{
"default-allow-path-allow": {
intentionDefaultAllow: true,
http: true,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
),
expect: []*rbacIntention{}, // EMPTY, just use the defaults
},
"default-deny-path-allow": {
intentionDefaultAllow: false,
http: true,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
),
expect: []*rbacIntention{
{
Source: nameWeb,
Action: intentionActionLayer7,
Permissions: []*rbacPermission{
{
Definition: permSlashPrefix,
Action: intentionActionAllow,
Perm: xdsPermSlashPrefix,
NotPerms: nil,
Skip: false,
ComputedPermission: xdsPermSlashPrefix,
},
},
Precedence: 9,
Skip: false,
ComputedPrincipal: idPrincipal(nameWeb),
},
},
},
"default-allow-path-deny": {
intentionDefaultAllow: true,
http: true,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
),
expect: []*rbacIntention{
{
Source: nameWeb,
Action: intentionActionLayer7,
Permissions: []*rbacPermission{
{
Definition: permDenySlashPrefix,
Action: intentionActionDeny,
Perm: xdsPermSlashPrefix,
NotPerms: nil,
Skip: false,
ComputedPermission: xdsPermSlashPrefix,
},
},
Precedence: 9,
Skip: false,
ComputedPrincipal: idPrincipal(nameWeb),
},
},
},
"default-deny-path-deny": {
intentionDefaultAllow: false,
http: true,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
),
expect: []*rbacIntention{},
},
// ========================
"default-allow-deny-all-and-path-allow": {
intentionDefaultAllow: true,
http: true,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
testSourceIntention("*", structs.IntentionActionDeny),
),
expect: []*rbacIntention{
{
Source: nameWild,
NotSources: []structs.ServiceName{
nameWeb,
},
Action: intentionActionDeny,
Permissions: nil,
Precedence: 8,
Skip: false,
ComputedPrincipal: andPrincipals(
[]*envoy_rbac_v3.Principal{
idPrincipal(nameWild),
notPrincipal(
idPrincipal(nameWeb),
),
},
),
},
},
},
"default-deny-deny-all-and-path-allow": {
intentionDefaultAllow: false,
http: true,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
testSourceIntention("*", structs.IntentionActionDeny),
),
expect: []*rbacIntention{
{
Source: nameWeb,
Action: intentionActionLayer7,
Permissions: []*rbacPermission{
{
Definition: permSlashPrefix,
Action: intentionActionAllow,
Perm: xdsPermSlashPrefix,
NotPerms: nil,
Skip: false,
ComputedPermission: xdsPermSlashPrefix,
},
},
Precedence: 9,
Skip: false,
ComputedPrincipal: idPrincipal(nameWeb),
},
},
},
"default-allow-deny-all-and-path-deny": {
intentionDefaultAllow: true,
http: true,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
testSourceIntention("*", structs.IntentionActionDeny),
),
expect: []*rbacIntention{
{
Source: nameWeb,
Action: intentionActionLayer7,
Permissions: []*rbacPermission{
{
Definition: permDenySlashPrefix,
Action: intentionActionDeny,
Perm: xdsPermSlashPrefix,
NotPerms: nil,
Skip: false,
ComputedPermission: xdsPermSlashPrefix,
},
},
Precedence: 9,
Skip: false,
ComputedPrincipal: idPrincipal(nameWeb),
},
{
Source: nameWild,
NotSources: []structs.ServiceName{
nameWeb,
},
Action: intentionActionDeny,
Permissions: nil,
Precedence: 8,
Skip: false,
ComputedPrincipal: andPrincipals(
[]*envoy_rbac_v3.Principal{
idPrincipal(nameWild),
notPrincipal(
idPrincipal(nameWeb),
),
},
),
},
},
},
"default-deny-deny-all-and-path-deny": {
intentionDefaultAllow: false,
http: true,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
testSourceIntention("*", structs.IntentionActionDeny),
),
expect: []*rbacIntention{},
},
// ========================
"default-allow-allow-all-and-path-allow": {
intentionDefaultAllow: true,
http: true,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
testSourceIntention("*", structs.IntentionActionAllow),
),
expect: []*rbacIntention{},
},
"default-deny-allow-all-and-path-allow": {
intentionDefaultAllow: false,
http: true,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
testSourceIntention("*", structs.IntentionActionAllow),
),
expect: []*rbacIntention{
{
Source: nameWeb,
Action: intentionActionLayer7,
Permissions: []*rbacPermission{
{
Definition: permSlashPrefix,
Action: intentionActionAllow,
Perm: xdsPermSlashPrefix,
NotPerms: nil,
Skip: false,
ComputedPermission: xdsPermSlashPrefix,
},
},
Precedence: 9,
Skip: false,
ComputedPrincipal: idPrincipal(nameWeb),
},
{
Source: nameWild,
NotSources: []structs.ServiceName{
nameWeb,
},
Action: intentionActionAllow,
Permissions: nil,
Precedence: 8,
Skip: false,
ComputedPrincipal: andPrincipals(
[]*envoy_rbac_v3.Principal{
idPrincipal(nameWild),
notPrincipal(
idPrincipal(nameWeb),
),
},
),
},
},
},
"default-allow-allow-all-and-path-deny": {
intentionDefaultAllow: true,
http: true,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
testSourceIntention("*", structs.IntentionActionAllow),
),
expect: []*rbacIntention{
{
Source: nameWeb,
Action: intentionActionLayer7,
Permissions: []*rbacPermission{
{
Definition: permDenySlashPrefix,
Action: intentionActionDeny,
Perm: xdsPermSlashPrefix,
NotPerms: nil,
Skip: false,
ComputedPermission: xdsPermSlashPrefix,
},
},
Precedence: 9,
Skip: false,
ComputedPrincipal: idPrincipal(nameWeb),
},
},
},
"default-deny-allow-all-and-path-deny": {
intentionDefaultAllow: false,
http: true,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
testSourceIntention("*", structs.IntentionActionAllow),
),
expect: []*rbacIntention{
{
Source: nameWild,
NotSources: []structs.ServiceName{
nameWeb,
},
Action: intentionActionAllow,
Permissions: nil,
Precedence: 8,
Skip: false,
ComputedPrincipal: andPrincipals(
[]*envoy_rbac_v3.Principal{
idPrincipal(nameWild),
notPrincipal(
idPrincipal(nameWeb),
),
},
),
},
},
},
}
for name, tt := range tests {
t.Run(name, func(t *testing.T) {
rbacIxns := intentionListToIntermediateRBACForm(tt.intentions, tt.http)
intentionDefaultAction := intentionActionFromBool(tt.intentionDefaultAllow)
rbacIxns = removeIntentionPrecedence(rbacIxns, intentionDefaultAction)
require.Equal(t, tt.expect, rbacIxns)
})
}
}
func TestMakeRBACNetworkAndHTTPFilters(t *testing.T) {
testIntention := func(t *testing.T, src, dst string, action structs.IntentionAction) *structs.Intention {
t.Helper()
ixn := structs.TestIntention(t)
ixn.SourceName = src
ixn.DestinationName = dst
ixn.Action = action
//nolint:staticcheck
ixn.UpdatePrecedence()
return ixn
}
testSourceIntention := func(src string, action structs.IntentionAction) *structs.Intention {
return testIntention(t, src, "api", action)
}
testSourcePermIntention := func(src string, perms ...*structs.IntentionPermission) *structs.Intention {
ixn := testIntention(t, src, "api", "")
ixn.Permissions = perms
return ixn
}
sorted := func(ixns ...*structs.Intention) structs.Intentions {
sort.SliceStable(ixns, func(i, j int) bool {
return ixns[j].Precedence < ixns[i].Precedence
})
return structs.Intentions(ixns)
}
var (
permSlashPrefix = &structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
}
permDenySlashPrefix = &structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
}
)
tests := map[string]struct {
intentionDefaultAllow bool
intentions structs.Intentions
}{
"default-deny-mixed-precedence": {
intentionDefaultAllow: false,
intentions: sorted(
testIntention(t, "web", "api", structs.IntentionActionAllow),
testIntention(t, "*", "api", structs.IntentionActionDeny),
testIntention(t, "web", "*", structs.IntentionActionDeny),
),
},
"default-deny-service-wildcard-allow": {
intentionDefaultAllow: false,
intentions: sorted(
testSourceIntention("*", structs.IntentionActionAllow),
),
},
"default-allow-service-wildcard-deny": {
intentionDefaultAllow: true,
intentions: sorted(
testSourceIntention("*", structs.IntentionActionDeny),
),
},
"default-deny-one-allow": {
intentionDefaultAllow: false,
intentions: sorted(
testSourceIntention("web", structs.IntentionActionAllow),
),
},
"default-allow-one-deny": {
intentionDefaultAllow: true,
intentions: sorted(
testSourceIntention("web", structs.IntentionActionDeny),
),
},
"default-deny-allow-deny": {
intentionDefaultAllow: false,
intentions: sorted(
testSourceIntention("web", structs.IntentionActionDeny),
testSourceIntention("*", structs.IntentionActionAllow),
),
},
"default-deny-kitchen-sink": {
intentionDefaultAllow: false,
intentions: sorted(
// (double exact)
testSourceIntention("web", structs.IntentionActionAllow),
testSourceIntention("unsafe", structs.IntentionActionDeny),
testSourceIntention("cron", structs.IntentionActionAllow),
testSourceIntention("*", structs.IntentionActionAllow),
),
},
"default-allow-kitchen-sink": {
intentionDefaultAllow: true,
intentions: sorted(
// (double exact)
testSourceIntention("web", structs.IntentionActionDeny),
testSourceIntention("unsafe", structs.IntentionActionAllow),
testSourceIntention("cron", structs.IntentionActionDeny),
testSourceIntention("*", structs.IntentionActionDeny),
),
},
// ========================
"default-allow-path-allow": {
intentionDefaultAllow: true,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
),
},
"default-deny-path-allow": {
intentionDefaultAllow: false,
intentions: sorted(
testSourcePermIntention("web", permSlashPrefix),
),
},
"default-allow-path-deny": {
intentionDefaultAllow: true,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
),
},
"default-deny-path-deny": {
intentionDefaultAllow: false,
intentions: sorted(
testSourcePermIntention("web", permDenySlashPrefix),
),
},
// ========================
"default-allow-deny-all-and-path-allow": {
intentionDefaultAllow: true,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
},
),
testSourceIntention("*", structs.IntentionActionDeny),
),
},
"default-deny-deny-all-and-path-allow": {
intentionDefaultAllow: false,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
},
),
testSourceIntention("*", structs.IntentionActionDeny),
),
},
"default-allow-deny-all-and-path-deny": {
intentionDefaultAllow: true,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
},
),
testSourceIntention("*", structs.IntentionActionDeny),
),
},
"default-deny-deny-all-and-path-deny": {
intentionDefaultAllow: false,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
},
),
testSourceIntention("*", structs.IntentionActionDeny),
),
},
// ========================
"default-deny-two-path-deny-and-path-allow": {
intentionDefaultAllow: false,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathExact: "/v1/secret",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathExact: "/v1/admin",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
},
),
),
},
"default-allow-two-path-deny-and-path-allow": {
intentionDefaultAllow: true,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathExact: "/v1/secret",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathExact: "/v1/admin",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/",
},
},
),
),
},
"default-deny-single-intention-with-kitchen-sink-perms": {
intentionDefaultAllow: false,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathExact: "/v1/secret",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/v1",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathRegex: "/v[123]",
Methods: []string{"GET", "HEAD", "OPTIONS"},
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
Header: []structs.IntentionHTTPHeaderPermission{
{Name: "x-foo", Present: true},
{Name: "x-bar", Exact: "xyz"},
{Name: "x-dib", Prefix: "gaz"},
{Name: "x-gir", Suffix: "zim"},
{Name: "x-zim", Regex: "gi[rR]"},
{Name: "z-foo", Present: true, Invert: true},
{Name: "z-bar", Exact: "xyz", Invert: true},
{Name: "z-dib", Prefix: "gaz", Invert: true},
{Name: "z-gir", Suffix: "zim", Invert: true},
{Name: "z-zim", Regex: "gi[rR]", Invert: true},
},
},
},
),
),
},
"default-allow-single-intention-with-kitchen-sink-perms": {
intentionDefaultAllow: true,
intentions: sorted(
testSourcePermIntention("web",
&structs.IntentionPermission{
Action: structs.IntentionActionAllow,
HTTP: &structs.IntentionHTTPPermission{
PathExact: "/v1/secret",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathPrefix: "/v1",
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
PathRegex: "/v[123]",
Methods: []string{"GET", "HEAD", "OPTIONS"},
},
},
&structs.IntentionPermission{
Action: structs.IntentionActionDeny,
HTTP: &structs.IntentionHTTPPermission{
Header: []structs.IntentionHTTPHeaderPermission{
{Name: "x-foo", Present: true},
{Name: "x-bar", Exact: "xyz"},
{Name: "x-dib", Prefix: "gaz"},
{Name: "x-gir", Suffix: "zim"},
{Name: "x-zim", Regex: "gi[rR]"},
{Name: "z-foo", Present: true, Invert: true},
{Name: "z-bar", Exact: "xyz", Invert: true},
{Name: "z-dib", Prefix: "gaz", Invert: true},
{Name: "z-gir", Suffix: "zim", Invert: true},
{Name: "z-zim", Regex: "gi[rR]", Invert: true},
},
},
},
),
),
},
}
for name, tt := range tests {
tt := tt
t.Run(name, func(t *testing.T) {
t.Run("network filter", func(t *testing.T) {
filter, err := makeRBACNetworkFilter(tt.intentions, tt.intentionDefaultAllow)
require.NoError(t, err)
t.Run("current", func(t *testing.T) {
gotJSON := protoToJSON(t, filter)
require.JSONEq(t, goldenSimple(t, filepath.Join("rbac", name), gotJSON), gotJSON)
})
t.Run("v2-compat", func(t *testing.T) {
filterV2, err := convertNetFilterToV2(filter)
require.NoError(t, err)
gotJSON := protoToJSON(t, filterV2)
require.JSONEq(t, goldenSimple(t, filepath.Join("rbac", name+".v2compat"), gotJSON), gotJSON)
})
})
t.Run("http filter", func(t *testing.T) {
filter, err := makeRBACHTTPFilter(tt.intentions, tt.intentionDefaultAllow)
require.NoError(t, err)
t.Run("current", func(t *testing.T) {
gotJSON := protoToJSON(t, filter)
require.JSONEq(t, goldenSimple(t, filepath.Join("rbac", name+"--httpfilter"), gotJSON), gotJSON)
})
t.Run("v2-compat", func(t *testing.T) {
filterV2, err := convertHttpFilterToV2(filter)
require.NoError(t, err)
gotJSON := protoToJSON(t, filterV2)
require.JSONEq(t, goldenSimple(t, filepath.Join("rbac", name+"--httpfilter.v2compat"), gotJSON), gotJSON)
})
})
})
}
}
func TestRemoveSameSourceIntentions(t *testing.T) {
testIntention := func(t *testing.T, src, dst string) *structs.Intention {
t.Helper()
ixn := structs.TestIntention(t)
ixn.SourceName = src
ixn.DestinationName = dst
//nolint:staticcheck
ixn.UpdatePrecedence()
return ixn
}
sorted := func(ixns ...*structs.Intention) structs.Intentions {
sort.SliceStable(ixns, func(i, j int) bool {
return ixns[j].Precedence < ixns[i].Precedence
})
return structs.Intentions(ixns)
}
tests := map[string]struct {
in structs.Intentions
expect structs.Intentions
}{
"empty": {},
"one": {
in: sorted(
testIntention(t, "*", "*"),
),
expect: sorted(
testIntention(t, "*", "*"),
),
},
"two with no match": {
in: sorted(
testIntention(t, "*", "foo"),
testIntention(t, "bar", "*"),
),
expect: sorted(
testIntention(t, "*", "foo"),
testIntention(t, "bar", "*"),
),
},
"two with match, exact": {
in: sorted(
testIntention(t, "bar", "foo"),
testIntention(t, "bar", "*"),
),
expect: sorted(
testIntention(t, "bar", "foo"),
),
},
"two with match, wildcard": {
in: sorted(
testIntention(t, "*", "foo"),
testIntention(t, "*", "*"),
),
expect: sorted(
testIntention(t, "*", "foo"),
),
},
}
for name, tc := range tests {
tc := tc
t.Run(name, func(t *testing.T) {
got := removeSameSourceIntentions(tc.in)
require.Equal(t, tc.expect, got)
})
}
}
func TestSimplifyNotSourceSlice(t *testing.T) {
tests := map[string]struct {
in []string
expect []string
}{
"empty": {},
"one": {
[]string{"bar"},
[]string{"bar"},
},
"two with no match": {
[]string{"foo", "bar"},
[]string{"foo", "bar"},
},
"two with match": {
[]string{"*", "bar"},
[]string{"*"},
},
"three with two matches down to one": {
[]string{"*", "foo", "bar"},
[]string{"*"},
},
}
for name, tc := range tests {
tc := tc
t.Run(name, func(t *testing.T) {
got := simplifyNotSourceSlice(makeServiceNameSlice(tc.in))
require.Equal(t, makeServiceNameSlice(tc.expect), got)
})
}
}
func TestIxnSourceMatches(t *testing.T) {
tests := []struct {
tester, against string
matches bool
}{
// identical precedence
{"web", "api", false},
{"*", "*", false},
// backwards precedence
{"*", "web", false},
// name wildcards
{"web", "*", true},
}
for _, tc := range tests {
t.Run(fmt.Sprintf("%s cmp %s", tc.tester, tc.against), func(t *testing.T) {
matches := ixnSourceMatches(
structs.ServiceNameFromString(tc.tester),
structs.ServiceNameFromString(tc.against),
)
assert.Equal(t, tc.matches, matches)
})
}
}
func makeServiceNameSlice(slice []string) []structs.ServiceName {
if len(slice) == 0 {
return nil
}
var out []structs.ServiceName
for _, src := range slice {
out = append(out, structs.ServiceNameFromString(src))
}
return out
}
func unmakeServiceNameSlice(slice []structs.ServiceName) []string {
if len(slice) == 0 {
return nil
}
var out []string
for _, src := range slice {
out = append(out, src.String())
}
return out
}