// Copyright (c) Tailscale Inc & AUTHORS // SPDX-License-Identifier: BSD-3-Clause //go:build linux package main import ( "bytes" _ "embed" "encoding/base64" "encoding/json" "encoding/pem" "errors" "fmt" "io" "io/fs" "net" "net/http" "net/http/httptest" "net/netip" "os" "os/exec" "path/filepath" "strconv" "strings" "sync" "testing" "time" "github.com/google/go-cmp/cmp" "golang.org/x/sys/unix" "tailscale.com/ipn" "tailscale.com/tailcfg" "tailscale.com/tstest" "tailscale.com/types/netmap" "tailscale.com/types/ptr" ) func TestContainerBoot(t *testing.T) { d := t.TempDir() lapi := localAPI{FSRoot: d} if err := lapi.Start(); err != nil { t.Fatal(err) } defer lapi.Close() kube := kubeServer{FSRoot: d} if err := kube.Start(); err != nil { t.Fatal(err) } defer kube.Close() dirs := []string{ "var/lib", "usr/bin", "tmp", "dev/net", "proc/sys/net/ipv4", "proc/sys/net/ipv6/conf/all", } for _, path := range dirs { if err := os.MkdirAll(filepath.Join(d, path), 0700); err != nil { t.Fatal(err) } } files := map[string][]byte{ "usr/bin/tailscaled": fakeTailscaled, "usr/bin/tailscale": fakeTailscale, "usr/bin/iptables": fakeTailscale, "usr/bin/ip6tables": fakeTailscale, "dev/net/tun": []byte(""), "proc/sys/net/ipv4/ip_forward": []byte("0"), "proc/sys/net/ipv6/conf/all/forwarding": []byte("0"), } resetFiles := func() { for path, content := range files { // Making everything executable is a little weird, but the // stuff that doesn't need to be executable doesn't care if we // do make it executable. if err := os.WriteFile(filepath.Join(d, path), content, 0700); err != nil { t.Fatal(err) } } } resetFiles() boot := filepath.Join(d, "containerboot") if err := exec.Command("go", "build", "-o", boot, "tailscale.com/cmd/containerboot").Run(); err != nil { t.Fatalf("Building containerboot: %v", err) } argFile := filepath.Join(d, "args") runningSockPath := filepath.Join(d, "tmp/tailscaled.sock") type phase struct { // If non-nil, send this IPN bus notification (and remember it as the // initial update for any future new watchers, then wait for all the // Waits below to be true before proceeding to the next phase. Notify *ipn.Notify // WantCmds is the commands that containerboot should run in this phase. WantCmds []string // WantKubeSecret is the secret keys/values that should exist in the // kube secret. WantKubeSecret map[string]string // WantFiles files that should exist in the container and their // contents. WantFiles map[string]string } runningNotify := &ipn.Notify{ State: ptr.To(ipn.Running), NetMap: &netmap.NetworkMap{ SelfNode: (&tailcfg.Node{ StableID: tailcfg.StableNodeID("myID"), Name: "test-node.test.ts.net", Addresses: []netip.Prefix{netip.MustParsePrefix("100.64.0.1/32")}, }).View(), }, } tests := []struct { Name string Env map[string]string KubeSecret map[string]string KubeDenyPatch bool Phases []phase }{ { // Out of the box default: runs in userspace mode, ephemeral storage, interactive login. Name: "no_args", Env: nil, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false", }, }, { Notify: runningNotify, }, }, }, { // Userspace mode, ephemeral storage, authkey provided on every run. Name: "authkey", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, }, { Notify: runningNotify, }, }, }, { // Userspace mode, ephemeral storage, authkey provided on every run. Name: "authkey-old-flag", Env: map[string]string{ "TS_AUTH_KEY": "tskey-key", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, }, { Notify: runningNotify, }, }, }, { Name: "authkey_disk_state", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", "TS_STATE_DIR": filepath.Join(d, "tmp"), }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, }, { Notify: runningNotify, }, }, }, { Name: "routes", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", "TS_ROUTES": "1.2.3.0/24,10.20.30.0/24", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key --advertise-routes=1.2.3.0/24,10.20.30.0/24", }, }, { Notify: runningNotify, WantFiles: map[string]string{ "proc/sys/net/ipv4/ip_forward": "0", "proc/sys/net/ipv6/conf/all/forwarding": "0", }, }, }, }, { Name: "routes_kernel_ipv4", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", "TS_ROUTES": "1.2.3.0/24,10.20.30.0/24", "TS_USERSPACE": "false", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key --advertise-routes=1.2.3.0/24,10.20.30.0/24", }, }, { Notify: runningNotify, WantFiles: map[string]string{ "proc/sys/net/ipv4/ip_forward": "1", "proc/sys/net/ipv6/conf/all/forwarding": "0", }, }, }, }, { Name: "routes_kernel_ipv6", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", "TS_ROUTES": "::/64,1::/64", "TS_USERSPACE": "false", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key --advertise-routes=::/64,1::/64", }, }, { Notify: runningNotify, WantFiles: map[string]string{ "proc/sys/net/ipv4/ip_forward": "0", "proc/sys/net/ipv6/conf/all/forwarding": "1", }, }, }, }, { Name: "routes_kernel_all_families", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", "TS_ROUTES": "::/64,1.2.3.0/24", "TS_USERSPACE": "false", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key --advertise-routes=::/64,1.2.3.0/24", }, }, { Notify: runningNotify, WantFiles: map[string]string{ "proc/sys/net/ipv4/ip_forward": "1", "proc/sys/net/ipv6/conf/all/forwarding": "1", }, }, }, }, { Name: "proxy", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", "TS_DEST_IP": "1.2.3.4", "TS_USERSPACE": "false", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, }, { Notify: runningNotify, WantCmds: []string{ "/usr/bin/iptables -t nat -I PREROUTING 1 -d 100.64.0.1 -j DNAT --to-destination 1.2.3.4", }, }, }, }, { Name: "authkey_once", Env: map[string]string{ "TS_AUTHKEY": "tskey-key", "TS_AUTH_ONCE": "true", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking", }, }, { Notify: &ipn.Notify{ State: ptr.To(ipn.NeedsLogin), }, WantCmds: []string{ "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, }, { Notify: runningNotify, }, }, }, { Name: "kube_storage", Env: map[string]string{ "KUBERNETES_SERVICE_HOST": kube.Host, "KUBERNETES_SERVICE_PORT_HTTPS": kube.Port, }, KubeSecret: map[string]string{ "authkey": "tskey-key", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=kube:tailscale --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, WantKubeSecret: map[string]string{ "authkey": "tskey-key", }, }, { Notify: runningNotify, WantKubeSecret: map[string]string{ "authkey": "tskey-key", "device_fqdn": "test-node.test.ts.net", "device_id": "myID", "device_ips": `["100.64.0.1"]`, }, }, }, }, { Name: "kube_disk_storage", Env: map[string]string{ "KUBERNETES_SERVICE_HOST": kube.Host, "KUBERNETES_SERVICE_PORT_HTTPS": kube.Port, // Explicitly set to an empty value, to override the default of "tailscale". "TS_KUBE_SECRET": "", "TS_STATE_DIR": filepath.Join(d, "tmp"), "TS_AUTHKEY": "tskey-key", }, KubeSecret: map[string]string{}, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, WantKubeSecret: map[string]string{}, }, { Notify: runningNotify, WantKubeSecret: map[string]string{}, }, }, }, { Name: "kube_storage_no_patch", Env: map[string]string{ "KUBERNETES_SERVICE_HOST": kube.Host, "KUBERNETES_SERVICE_PORT_HTTPS": kube.Port, "TS_AUTHKEY": "tskey-key", }, KubeSecret: map[string]string{}, KubeDenyPatch: true, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=kube:tailscale --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, WantKubeSecret: map[string]string{}, }, { Notify: runningNotify, WantKubeSecret: map[string]string{}, }, }, }, { // Same as previous, but deletes the authkey from the kube secret. Name: "kube_storage_auth_once", Env: map[string]string{ "KUBERNETES_SERVICE_HOST": kube.Host, "KUBERNETES_SERVICE_PORT_HTTPS": kube.Port, "TS_AUTH_ONCE": "true", }, KubeSecret: map[string]string{ "authkey": "tskey-key", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=kube:tailscale --statedir=/tmp --tun=userspace-networking", }, WantKubeSecret: map[string]string{ "authkey": "tskey-key", }, }, { Notify: &ipn.Notify{ State: ptr.To(ipn.NeedsLogin), }, WantCmds: []string{ "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, WantKubeSecret: map[string]string{ "authkey": "tskey-key", }, }, { Notify: runningNotify, WantKubeSecret: map[string]string{ "device_fqdn": "test-node.test.ts.net", "device_id": "myID", "device_ips": `["100.64.0.1"]`, }, }, }, }, { Name: "kube_storage_updates", Env: map[string]string{ "KUBERNETES_SERVICE_HOST": kube.Host, "KUBERNETES_SERVICE_PORT_HTTPS": kube.Port, }, KubeSecret: map[string]string{ "authkey": "tskey-key", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=kube:tailscale --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --authkey=tskey-key", }, WantKubeSecret: map[string]string{ "authkey": "tskey-key", }, }, { Notify: runningNotify, WantKubeSecret: map[string]string{ "authkey": "tskey-key", "device_fqdn": "test-node.test.ts.net", "device_id": "myID", "device_ips": `["100.64.0.1"]`, }, }, { Notify: &ipn.Notify{ State: ptr.To(ipn.Running), NetMap: &netmap.NetworkMap{ SelfNode: (&tailcfg.Node{ StableID: tailcfg.StableNodeID("newID"), Name: "new-name.test.ts.net", Addresses: []netip.Prefix{netip.MustParsePrefix("100.64.0.1/32")}, }).View(), }, }, WantKubeSecret: map[string]string{ "authkey": "tskey-key", "device_fqdn": "new-name.test.ts.net", "device_id": "newID", "device_ips": `["100.64.0.1"]`, }, }, }, }, { Name: "proxies", Env: map[string]string{ "TS_SOCKS5_SERVER": "localhost:1080", "TS_OUTBOUND_HTTP_PROXY_LISTEN": "localhost:8080", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking --socks5-server=localhost:1080 --outbound-http-proxy-listen=localhost:8080", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false", }, }, { Notify: runningNotify, }, }, }, { Name: "dns", Env: map[string]string{ "TS_ACCEPT_DNS": "true", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=true", }, }, { Notify: runningNotify, }, }, }, { Name: "extra_args", Env: map[string]string{ "TS_EXTRA_ARGS": "--widget=rotated", "TS_TAILSCALED_EXTRA_ARGS": "--experiments=widgets", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking --experiments=widgets", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --widget=rotated", }, }, { Notify: runningNotify, }, }, }, { Name: "hostname", Env: map[string]string{ "TS_HOSTNAME": "my-server", }, Phases: []phase{ { WantCmds: []string{ "/usr/bin/tailscaled --socket=/tmp/tailscaled.sock --state=mem: --statedir=/tmp --tun=userspace-networking", "/usr/bin/tailscale --socket=/tmp/tailscaled.sock up --accept-dns=false --hostname=my-server", }, }, { Notify: runningNotify, }, }, }, } for _, test := range tests { t.Run(test.Name, func(t *testing.T) { lapi.Reset() kube.Reset() os.Remove(argFile) os.Remove(runningSockPath) resetFiles() for k, v := range test.KubeSecret { kube.SetSecret(k, v) } kube.SetPatching(!test.KubeDenyPatch) cmd := exec.Command(boot) cmd.Env = []string{ fmt.Sprintf("PATH=%s/usr/bin:%s", d, os.Getenv("PATH")), fmt.Sprintf("TS_TEST_RECORD_ARGS=%s", argFile), fmt.Sprintf("TS_TEST_SOCKET=%s", lapi.Path), fmt.Sprintf("TS_SOCKET=%s", runningSockPath), fmt.Sprintf("TS_TEST_ONLY_ROOT=%s", d), } for k, v := range test.Env { cmd.Env = append(cmd.Env, fmt.Sprintf("%s=%s", k, v)) } cbOut := &lockingBuffer{} defer func() { if t.Failed() { t.Logf("containerboot output:\n%s", cbOut.String()) } }() cmd.Stderr = cbOut if err := cmd.Start(); err != nil { t.Fatalf("starting containerboot: %v", err) } defer func() { cmd.Process.Signal(unix.SIGTERM) cmd.Process.Wait() }() var wantCmds []string for i, p := range test.Phases { lapi.Notify(p.Notify) wantCmds = append(wantCmds, p.WantCmds...) waitArgs(t, 2*time.Second, d, argFile, strings.Join(wantCmds, "\n")) err := tstest.WaitFor(2*time.Second, func() error { if p.WantKubeSecret != nil { got := kube.Secret() if diff := cmp.Diff(got, p.WantKubeSecret); diff != "" { return fmt.Errorf("unexpected kube secret data (-got+want):\n%s", diff) } } else { got := kube.Secret() if len(got) > 0 { return fmt.Errorf("kube secret unexpectedly not empty, got %#v", got) } } return nil }) if err != nil { t.Fatalf("phase %d: %v", i, err) } err = tstest.WaitFor(2*time.Second, func() error { for path, want := range p.WantFiles { gotBs, err := os.ReadFile(filepath.Join(d, path)) if err != nil { return fmt.Errorf("reading wanted file %q: %v", path, err) } if got := strings.TrimSpace(string(gotBs)); got != want { return fmt.Errorf("wrong file contents for %q, got %q want %q", path, got, want) } } return nil }) if err != nil { t.Fatal(err) } } waitLogLine(t, 2*time.Second, cbOut, "Startup complete, waiting for shutdown signal") }) } } type lockingBuffer struct { sync.Mutex b bytes.Buffer } func (b *lockingBuffer) Write(bs []byte) (int, error) { b.Lock() defer b.Unlock() return b.b.Write(bs) } func (b *lockingBuffer) String() string { b.Lock() defer b.Unlock() return b.b.String() } // waitLogLine looks for want in the contents of b. // // Only lines starting with 'boot: ' (the output of containerboot // itself) are considered, and the logged timestamp is ignored. // // waitLogLine fails the entire test if path doesn't contain want // before the timeout. func waitLogLine(t *testing.T, timeout time.Duration, b *lockingBuffer, want string) { deadline := time.Now().Add(timeout) for time.Now().Before(deadline) { for _, line := range strings.Split(b.String(), "\n") { if !strings.HasPrefix(line, "boot: ") { continue } if strings.HasSuffix(line, " "+want) { return } } time.Sleep(100 * time.Millisecond) } t.Fatalf("timed out waiting for wanted output line %q. Output:\n%s", want, b.String()) } // waitArgs waits until the contents of path matches wantArgs, a set // of command lines recorded by test_tailscale.sh and // test_tailscaled.sh. // // All occurrences of removeStr are removed from the file prior to // comparison. This is used to remove the varying temporary root // directory name from recorded commandlines, so that wantArgs can be // a constant value. // // waitArgs fails the entire test if path doesn't contain wantArgs // before the timeout. func waitArgs(t *testing.T, timeout time.Duration, removeStr, path, wantArgs string) { t.Helper() wantArgs = strings.TrimSpace(wantArgs) deadline := time.Now().Add(timeout) var got string for time.Now().Before(deadline) { bs, err := os.ReadFile(path) if errors.Is(err, fs.ErrNotExist) { // Don't bother logging that the file doesn't exist, it // should start existing soon. goto loop } else if err != nil { t.Logf("reading %q: %v", path, err) goto loop } got = strings.TrimSpace(string(bs)) got = strings.ReplaceAll(got, removeStr, "") if got == wantArgs { return } loop: time.Sleep(100 * time.Millisecond) } t.Fatalf("waiting for args file %q to have expected output, got:\n%s\n\nWant: %s", path, got, wantArgs) } //go:embed test_tailscaled.sh var fakeTailscaled []byte //go:embed test_tailscale.sh var fakeTailscale []byte // localAPI is a minimal fake tailscaled LocalAPI server that presents // just enough functionality for containerboot to function // correctly. In practice this means it only supports querying // tailscaled status, and panics on all other uses to make it very // obvious that something unexpected happened. type localAPI struct { FSRoot string Path string // populated by Start srv *http.Server sync.Mutex cond *sync.Cond notify *ipn.Notify } func (l *localAPI) Start() error { path := filepath.Join(l.FSRoot, "tmp/tailscaled.sock.fake") if err := os.MkdirAll(filepath.Dir(path), 0700); err != nil { return err } ln, err := net.Listen("unix", path) if err != nil { return err } l.srv = &http.Server{ Handler: l, } l.Path = path l.cond = sync.NewCond(&l.Mutex) go l.srv.Serve(ln) return nil } func (l *localAPI) Close() { l.srv.Close() } func (l *localAPI) Reset() { l.Lock() defer l.Unlock() l.notify = nil l.cond.Broadcast() } func (l *localAPI) Notify(n *ipn.Notify) { if n == nil { return } l.Lock() defer l.Unlock() l.notify = n l.cond.Broadcast() } func (l *localAPI) ServeHTTP(w http.ResponseWriter, r *http.Request) { if r.Method != "GET" { panic(fmt.Sprintf("unsupported method %q", r.Method)) } if r.URL.Path != "/localapi/v0/watch-ipn-bus" { panic(fmt.Sprintf("unsupported path %q", r.URL.Path)) } w.Header().Set("Content-Type", "application/json") w.WriteHeader(http.StatusOK) if f, ok := w.(http.Flusher); ok { f.Flush() } enc := json.NewEncoder(w) l.Lock() defer l.Unlock() for { if l.notify != nil { if err := enc.Encode(l.notify); err != nil { // Usually broken pipe as the test client disconnects. return } if f, ok := w.(http.Flusher); ok { f.Flush() } } l.cond.Wait() } } // kubeServer is a minimal fake Kubernetes server that presents just // enough functionality for containerboot to function correctly. In // practice this means it only supports reading and modifying a single // kube secret, and panics on all other uses to make it very obvious // that something unexpected happened. type kubeServer struct { FSRoot string Host, Port string // populated by Start srv *httptest.Server sync.Mutex secret map[string]string canPatch bool } func (k *kubeServer) Secret() map[string]string { k.Lock() defer k.Unlock() ret := map[string]string{} for k, v := range k.secret { ret[k] = v } return ret } func (k *kubeServer) SetSecret(key, val string) { k.Lock() defer k.Unlock() k.secret[key] = val } func (k *kubeServer) SetPatching(canPatch bool) { k.Lock() defer k.Unlock() k.canPatch = canPatch } func (k *kubeServer) Reset() { k.Lock() defer k.Unlock() k.secret = map[string]string{} } func (k *kubeServer) Start() error { root := filepath.Join(k.FSRoot, "var/run/secrets/kubernetes.io/serviceaccount") if err := os.MkdirAll(root, 0700); err != nil { return err } if err := os.WriteFile(filepath.Join(root, "namespace"), []byte("default"), 0600); err != nil { return err } if err := os.WriteFile(filepath.Join(root, "token"), []byte("bearer_token"), 0600); err != nil { return err } k.srv = httptest.NewTLSServer(k) k.Host = k.srv.Listener.Addr().(*net.TCPAddr).IP.String() k.Port = strconv.Itoa(k.srv.Listener.Addr().(*net.TCPAddr).Port) var cert bytes.Buffer if err := pem.Encode(&cert, &pem.Block{Type: "CERTIFICATE", Bytes: k.srv.Certificate().Raw}); err != nil { return err } if err := os.WriteFile(filepath.Join(root, "ca.crt"), cert.Bytes(), 0600); err != nil { return err } return nil } func (k *kubeServer) Close() { k.srv.Close() } func (k *kubeServer) ServeHTTP(w http.ResponseWriter, r *http.Request) { if r.Header.Get("Authorization") != "Bearer bearer_token" { panic("client didn't provide bearer token in request") } switch r.URL.Path { case "/api/v1/namespaces/default/secrets/tailscale": k.serveSecret(w, r) case "/apis/authorization.k8s.io/v1/selfsubjectaccessreviews": k.serveSSAR(w, r) default: panic(fmt.Sprintf("unhandled fake kube api path %q", r.URL.Path)) } } func (k *kubeServer) serveSSAR(w http.ResponseWriter, r *http.Request) { var req struct { Spec struct { ResourceAttributes struct { Verb string `json:"verb"` } `json:"resourceAttributes"` } `json:"spec"` } if err := json.NewDecoder(r.Body).Decode(&req); err != nil { panic(fmt.Sprintf("decoding SSAR request: %v", err)) } ok := true if req.Spec.ResourceAttributes.Verb == "patch" { k.Lock() defer k.Unlock() ok = k.canPatch } // Just say yes to all SARs, we don't enforce RBAC. w.Header().Set("Content-Type", "application/json") fmt.Fprintf(w, `{"status":{"allowed":%v}}`, ok) } func (k *kubeServer) serveSecret(w http.ResponseWriter, r *http.Request) { bs, err := io.ReadAll(r.Body) if err != nil { http.Error(w, fmt.Sprintf("reading request body: %v", err), http.StatusInternalServerError) return } switch r.Method { case "GET": w.Header().Set("Content-Type", "application/json") ret := map[string]map[string]string{ "data": {}, } k.Lock() defer k.Unlock() for k, v := range k.secret { v := base64.StdEncoding.EncodeToString([]byte(v)) if err != nil { panic("encode failed") } ret["data"][k] = v } if err := json.NewEncoder(w).Encode(ret); err != nil { panic("encode failed") } case "PATCH": k.Lock() defer k.Unlock() if !k.canPatch { panic("containerboot tried to patch despite not being allowed") } switch r.Header.Get("Content-Type") { case "application/json-patch+json": req := []struct { Op string `json:"op"` Path string `json:"path"` }{} if err := json.Unmarshal(bs, &req); err != nil { panic(fmt.Sprintf("json decode failed: %v. Body:\n\n%s", err, string(bs))) } for _, op := range req { if op.Op != "remove" { panic(fmt.Sprintf("unsupported json-patch op %q", op.Op)) } if !strings.HasPrefix(op.Path, "/data/") { panic(fmt.Sprintf("unsupported json-patch path %q", op.Path)) } delete(k.secret, strings.TrimPrefix(op.Path, "/data/")) } case "application/strategic-merge-patch+json": req := struct { Data map[string][]byte `json:"data"` }{} if err := json.Unmarshal(bs, &req); err != nil { panic(fmt.Sprintf("json decode failed: %v. Body:\n\n%s", err, string(bs))) } for key, val := range req.Data { k.secret[key] = string(val) } default: panic(fmt.Sprintf("unknown content type %q", r.Header.Get("Content-Type"))) } default: panic(fmt.Sprintf("unhandled HTTP method %q", r.Method)) } }