f-50: lab: image vérifiée, disques et seeds des VM #50

Signed-off-by: GnomeZworc <nicolas.boufidjeline@g3e.fr>
This commit is contained in:
GnomeZworc 2026-10-04 14:21:20 +02:00
commit 4b176c22d7
Signed by: nicolas.boufideline
GPG key ID: 4406BBBF8845D632
7 changed files with 999 additions and 20 deletions

View file

@ -8,6 +8,7 @@ import (
"path/filepath" "path/filepath"
"strings" "strings"
"git.g3e.fr/syonad/two/internal/lab/provision"
"git.g3e.fr/syonad/two/internal/lab/render" "git.g3e.fr/syonad/two/internal/lab/render"
"git.g3e.fr/syonad/two/internal/lab/topology" "git.g3e.fr/syonad/two/internal/lab/topology"
) )
@ -111,7 +112,7 @@ func renderCmd(args []string, stdout, stderr io.Writer) int {
return 1 return 1
} }
for _, n := range nodes { for _, n := range nodes {
if err := writeNode(n); err != nil { if err := provision.WriteFiles(n); err != nil {
fmt.Fprintf(stderr, "lab: %v\n", err) fmt.Fprintf(stderr, "lab: %v\n", err)
return 1 return 1
} }
@ -137,21 +138,3 @@ func readKeys(files []string) ([]string, error) {
} }
return keys, nil return keys, nil
} }
func writeNode(n render.Node) error {
if err := os.MkdirAll(n.Dir, 0o700); err != nil {
return err
}
files := map[string][]byte{
"qemu.args": []byte(strings.Join(n.QEMU, "\n") + "\n"),
"meta-data": n.MetaData,
"user-data": n.UserData,
"network-config": n.NetworkConfig,
}
for name, content := range files {
if err := os.WriteFile(filepath.Join(n.Dir, name), content, 0o600); err != nil {
return err
}
}
return nil
}

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@ -0,0 +1,185 @@
package provision
import (
"bufio"
"bytes"
"context"
"crypto/sha512"
"encoding/hex"
"errors"
"fmt"
"io"
"net/http"
"net/url"
"os"
"path"
"path/filepath"
"regexp"
"strings"
"git.g3e.fr/syonad/two/internal/lab/topology"
)
const maxSumsSize = 1 << 20
var sha512Pattern = regexp.MustCompile(`^[0-9a-f]{128}$`)
type Fetcher struct {
Client *http.Client
CacheDir string
}
func (f Fetcher) Image(ctx context.Context, img topology.Image) (string, error) {
if !filepath.IsAbs(f.CacheDir) {
return "", fmt.Errorf("image cache dir %q must be an absolute path", f.CacheDir)
}
name, err := fileName(img.URL)
if err != nil {
return "", fmt.Errorf("image %s: %w", img.Name, err)
}
sums, err := f.get(ctx, img.Sums, maxSumsSize)
if err != nil {
return "", fmt.Errorf("image %s: sums: %w", img.Name, err)
}
want, err := expectedSum(sums, name)
if err != nil {
return "", fmt.Errorf("image %s: %s: %w", img.Name, img.Sums, err)
}
dir := filepath.Join(f.CacheDir, img.Name)
target := filepath.Join(dir, name)
if got, err := fileSum(target); err == nil && got == want {
return target, nil
} else if err != nil && !errors.Is(err, os.ErrNotExist) {
return "", fmt.Errorf("image %s: %w", img.Name, err)
}
if err := os.MkdirAll(dir, 0o755); err != nil {
return "", err
}
if err := f.download(ctx, img.URL, dir, target, want); err != nil {
return "", fmt.Errorf("image %s: %w", img.Name, err)
}
return target, nil
}
func (f Fetcher) client() *http.Client {
if f.Client != nil {
return f.Client
}
return http.DefaultClient
}
func (f Fetcher) open(ctx context.Context, rawURL string) (*http.Response, error) {
req, err := http.NewRequestWithContext(ctx, http.MethodGet, rawURL, nil)
if err != nil {
return nil, err
}
resp, err := f.client().Do(req)
if err != nil {
return nil, err
}
if resp.StatusCode != http.StatusOK {
resp.Body.Close()
return nil, fmt.Errorf("GET %s: %s", rawURL, resp.Status)
}
return resp, nil
}
func (f Fetcher) get(ctx context.Context, rawURL string, limit int64) ([]byte, error) {
resp, err := f.open(ctx, rawURL)
if err != nil {
return nil, err
}
defer resp.Body.Close()
data, err := io.ReadAll(io.LimitReader(resp.Body, limit+1))
if err != nil {
return nil, err
}
if int64(len(data)) > limit {
return nil, fmt.Errorf("GET %s: larger than %d bytes", rawURL, limit)
}
return data, nil
}
func (f Fetcher) download(ctx context.Context, rawURL, dir, target, want string) error {
resp, err := f.open(ctx, rawURL)
if err != nil {
return err
}
defer resp.Body.Close()
tmp, err := os.CreateTemp(dir, filepath.Base(target)+".part-*")
if err != nil {
return err
}
defer os.Remove(tmp.Name())
h := sha512.New()
if _, err := io.Copy(io.MultiWriter(tmp, h), resp.Body); err != nil {
tmp.Close()
return fmt.Errorf("GET %s: %w", rawURL, err)
}
if err := tmp.Close(); err != nil {
return err
}
if got := hex.EncodeToString(h.Sum(nil)); got != want {
return fmt.Errorf("GET %s: sha512 %s, want %s", rawURL, got, want)
}
if err := os.Chmod(tmp.Name(), 0o644); err != nil {
return err
}
return os.Rename(tmp.Name(), target)
}
func fileName(rawURL string) (string, error) {
u, err := url.Parse(rawURL)
if err != nil {
return "", err
}
name := path.Base(u.Path)
if name == "" || name == "." || name == "/" {
return "", fmt.Errorf("url %q does not name a file", rawURL)
}
return name, nil
}
func expectedSum(sums []byte, name string) (string, error) {
var found []string
sc := bufio.NewScanner(bytes.NewReader(sums))
for sc.Scan() {
fields := strings.Fields(sc.Text())
if len(fields) != 2 || strings.TrimPrefix(fields[1], "*") != name {
continue
}
sum := strings.ToLower(fields[0])
if !sha512Pattern.MatchString(sum) {
return "", fmt.Errorf("entry for %s is not a sha512 sum", name)
}
found = append(found, sum)
}
if err := sc.Err(); err != nil {
return "", err
}
switch {
case len(found) == 0:
return "", fmt.Errorf("no sum for %s", name)
case len(found) > 1:
return "", fmt.Errorf("%d sums for %s", len(found), name)
}
return found[0], nil
}
func fileSum(p string) (string, error) {
file, err := os.Open(p)
if err != nil {
return "", err
}
defer file.Close()
h := sha512.New()
if _, err := io.Copy(h, file); err != nil {
return "", err
}
return hex.EncodeToString(h.Sum(nil)), nil
}

View file

@ -0,0 +1,334 @@
package provision
import (
"context"
"crypto/sha512"
"encoding/hex"
"net/http"
"net/http/httptest"
"os"
"path/filepath"
"strings"
"sync"
"testing"
"git.g3e.fr/syonad/two/internal/lab/topology"
)
const imageName = "debian-12-generic-amd64.qcow2"
type mirror struct {
mu sync.Mutex
files map[string][]byte
status map[string]int
hits map[string]int
server *httptest.Server
}
func newMirror(t *testing.T) *mirror {
t.Helper()
m := &mirror{files: map[string][]byte{}, status: map[string]int{}, hits: map[string]int{}}
m.server = httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
m.mu.Lock()
defer m.mu.Unlock()
m.hits[r.URL.Path]++
if code := m.status[r.URL.Path]; code != 0 {
w.WriteHeader(code)
return
}
data, ok := m.files[r.URL.Path]
if !ok {
http.NotFound(w, r)
return
}
w.Write(data)
}))
t.Cleanup(m.server.Close)
return m
}
func (m *mirror) put(path string, data []byte) {
m.mu.Lock()
defer m.mu.Unlock()
m.files[path] = data
}
func (m *mirror) count(path string) int {
m.mu.Lock()
defer m.mu.Unlock()
return m.hits[path]
}
func (m *mirror) image() topology.Image {
return topology.Image{
Name: "debian12",
URL: m.server.URL + "/bookworm/latest/" + imageName,
Sums: m.server.URL + "/bookworm/latest/SHA512SUMS",
}
}
func sum(data []byte) string {
h := sha512.Sum512(data)
return hex.EncodeToString(h[:])
}
func publish(m *mirror, content []byte) {
m.put("/bookworm/latest/"+imageName, content)
m.put("/bookworm/latest/SHA512SUMS", []byte(
sum([]byte("other"))+" debian-12-genericcloud-amd64.qcow2\n"+
sum(content)+" "+imageName+"\n"+
sum([]byte("raw"))+" debian-12-generic-amd64.raw\n"))
}
func fetch(t *testing.T, m *mirror, cache string) string {
t.Helper()
got, err := Fetcher{Client: m.server.Client(), CacheDir: cache}.Image(context.Background(), m.image())
if err != nil {
t.Fatalf("Image: %v", err)
}
return got
}
func fetchError(t *testing.T, m *mirror, cache string) string {
t.Helper()
_, err := Fetcher{Client: m.server.Client(), CacheDir: cache}.Image(context.Background(), m.image())
if err == nil {
t.Fatal("Image: no error")
}
return err.Error()
}
func entries(t *testing.T, dir string) []string {
t.Helper()
list, err := os.ReadDir(dir)
if err != nil && !os.IsNotExist(err) {
t.Fatal(err)
}
var names []string
for _, e := range list {
names = append(names, e.Name())
}
return names
}
func TestImage_DownloadsAndVerifies(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
cache := t.TempDir()
got := fetch(t, m, cache)
if want := filepath.Join(cache, "debian12", "debian-12-generic-amd64.qcow2"); got != want {
t.Errorf("path = %s, want %s", got, want)
}
data, err := os.ReadFile(got)
if err != nil || string(data) != "qcow2 image" {
t.Errorf("content = %q, %v", data, err)
}
info, err := os.Stat(got)
if err != nil || info.Mode().Perm() != 0o644 {
t.Errorf("mode = %v, %v", info.Mode().Perm(), err)
}
if names := entries(t, filepath.Join(cache, "debian12")); len(names) != 1 {
t.Errorf("cache dir holds %v, want only the image", names)
}
}
func TestImage_ReusesAVerifiedCacheButAlwaysRereadsTheSums(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
cache := t.TempDir()
fetch(t, m, cache)
fetch(t, m, cache)
if n := m.count("/bookworm/latest/" + imageName); n != 1 {
t.Errorf("image downloaded %d times, want 1", n)
}
if n := m.count("/bookworm/latest/SHA512SUMS"); n != 2 {
t.Errorf("sums read %d times, want 2", n)
}
}
func TestImage_ReplacesACorruptedCache(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
cache := t.TempDir()
path := fetch(t, m, cache)
if err := os.WriteFile(path, []byte("bit rot"), 0o644); err != nil {
t.Fatal(err)
}
fetch(t, m, cache)
if data, _ := os.ReadFile(path); string(data) != "qcow2 image" {
t.Errorf("content = %q, want the published image", data)
}
if n := m.count("/bookworm/latest/" + imageName); n != 2 {
t.Errorf("image downloaded %d times, want 2", n)
}
}
func TestImage_FollowsANewReleaseOfTheSameFile(t *testing.T) {
m := newMirror(t)
publish(m, []byte("release 1"))
cache := t.TempDir()
path := fetch(t, m, cache)
publish(m, []byte("release 2"))
fetch(t, m, cache)
if data, _ := os.ReadFile(path); string(data) != "release 2" {
t.Errorf("content = %q, want release 2", data)
}
}
func TestImage_RejectsAMismatchAndLeavesNothing(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
m.put("/bookworm/latest/"+imageName, []byte("tampered"))
cache := t.TempDir()
msg := fetchError(t, m, cache)
if !strings.Contains(msg, "sha512") {
t.Errorf("error = %q, want a sha512 mismatch", msg)
}
if names := entries(t, filepath.Join(cache, "debian12")); len(names) != 0 {
t.Errorf("cache dir holds %v after a mismatch, want nothing", names)
}
}
func TestImage_KeepsTheVerifiedCacheWhenANewDownloadFails(t *testing.T) {
m := newMirror(t)
publish(m, []byte("release 1"))
cache := t.TempDir()
path := fetch(t, m, cache)
publish(m, []byte("release 2"))
m.put("/bookworm/latest/"+imageName, []byte("truncated"))
fetchError(t, m, cache)
if data, _ := os.ReadFile(path); string(data) != "release 1" {
t.Errorf("content = %q, want release 1 kept", data)
}
if names := entries(t, filepath.Join(cache, "debian12")); len(names) != 1 {
t.Errorf("cache dir holds %v, want only the image", names)
}
}
func TestImage_AcceptsBinaryModeSumLines(t *testing.T) {
m := newMirror(t)
content := []byte("qcow2 image")
m.put("/bookworm/latest/"+imageName, content)
m.put("/bookworm/latest/SHA512SUMS", []byte(strings.ToUpper(sum(content))+" *"+imageName+"\n"))
fetch(t, m, t.TempDir())
}
func TestImage_SumsRejections(t *testing.T) {
content := []byte("qcow2 image")
cases := map[string]struct {
sums string
want string
}{
"no entry": {sum(content) + " debian-12-generic-arm64.qcow2\n", "no sum for " + imageName},
"two entries": {sum(content) + " " + imageName + "\n" + sum(content) + " " + imageName + "\n", "2 sums for " + imageName},
"not sha512": {"d41d8cd98f00b204e9800998ecf8427e " + imageName + "\n", "is not a sha512 sum"},
"prefix of name": {sum(content) + " " + imageName + ".sig\n", "no sum for " + imageName},
"name in directory": {sum(content) + " nested/" + imageName + "\n", "no sum for " + imageName},
}
for name, c := range cases {
t.Run(name, func(t *testing.T) {
m := newMirror(t)
m.put("/bookworm/latest/"+imageName, content)
m.put("/bookworm/latest/SHA512SUMS", []byte(c.sums))
if msg := fetchError(t, m, t.TempDir()); !strings.Contains(msg, c.want) {
t.Errorf("error = %q, want %q", msg, c.want)
}
if n := m.count("/bookworm/latest/" + imageName); n != 0 {
t.Errorf("image downloaded %d times before the sums were trusted", n)
}
})
}
}
func TestImage_RefusesOversizedSums(t *testing.T) {
m := newMirror(t)
m.put("/bookworm/latest/SHA512SUMS", make([]byte, 1<<20+1))
if msg := fetchError(t, m, t.TempDir()); !strings.Contains(msg, "larger than 1048576 bytes") {
t.Errorf("error = %q", msg)
}
}
func TestImage_AcceptsSumsOfExactlyTheLimit(t *testing.T) {
m := newMirror(t)
content := []byte("qcow2 image")
line := sum(content) + " " + imageName + "\n"
m.put("/bookworm/latest/"+imageName, content)
m.put("/bookworm/latest/SHA512SUMS", []byte(strings.Repeat("\n", 1<<20-len(line))+line))
fetch(t, m, t.TempDir())
}
func TestImage_HTTPErrors(t *testing.T) {
for _, path := range []string{"/bookworm/latest/SHA512SUMS", "/bookworm/latest/" + imageName} {
t.Run(path, func(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
m.status[path] = http.StatusServiceUnavailable
cache := t.TempDir()
if msg := fetchError(t, m, cache); !strings.Contains(msg, "503") {
t.Errorf("error = %q, want the http status", msg)
}
if names := entries(t, filepath.Join(cache, "debian12")); len(names) != 0 {
t.Errorf("cache dir holds %v, want nothing", names)
}
})
}
}
func TestImage_RefusesARelativeCacheDir(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
if msg := fetchError(t, m, "cache"); !strings.Contains(msg, "must be an absolute path") {
t.Errorf("error = %q", msg)
}
if n := m.count("/bookworm/latest/SHA512SUMS"); n != 0 {
t.Errorf("sums read %d times", n)
}
}
func TestImage_RefusesAURLWithoutFileName(t *testing.T) {
m := newMirror(t)
img := m.image()
img.URL = m.server.URL + "/"
_, err := Fetcher{Client: m.server.Client(), CacheDir: t.TempDir()}.Image(context.Background(), img)
if err == nil || !strings.Contains(err.Error(), "does not name a file") {
t.Errorf("error = %v", err)
}
}
func TestImage_RejectsAnInterruptedDownloadAndLeavesNothing(t *testing.T) {
content := []byte("qcow2 image")
server := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if strings.HasSuffix(r.URL.Path, "SHA512SUMS") {
w.Write([]byte(sum(content) + " " + imageName + "\n"))
return
}
w.Header().Set("Content-Length", "1000")
w.Write(content[:4])
}))
defer server.Close()
cache := t.TempDir()
img := topology.Image{Name: "debian12", URL: server.URL + "/" + imageName, Sums: server.URL + "/SHA512SUMS"}
_, err := Fetcher{Client: server.Client(), CacheDir: cache}.Image(context.Background(), img)
if err == nil || !strings.Contains(err.Error(), "unexpected EOF") {
t.Errorf("error = %v, want an interrupted transfer", err)
}
if names := entries(t, filepath.Join(cache, "debian12")); len(names) != 0 {
t.Errorf("cache dir holds %v, want nothing", names)
}
}

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@ -0,0 +1,151 @@
package provision
import (
"context"
"errors"
"fmt"
"os"
"os/exec"
"path/filepath"
"strings"
"git.g3e.fr/syonad/two/internal/lab/render"
"git.g3e.fr/syonad/two/internal/lab/topology"
)
const (
KeyFile = "lab_ed25519"
KeyLabel = "two-lab"
DiskSize = "20G"
SeedLabel = "cidata"
ArgsFile = "qemu.args"
)
var SeedFiles = []string{"user-data", "meta-data", "network-config"}
type Runner interface {
Run(ctx context.Context, name string, args ...string) error
}
type ExecRunner struct{}
func (ExecRunner) Run(ctx context.Context, name string, args ...string) error {
out, err := exec.CommandContext(ctx, name, args...).CombinedOutput()
if err != nil {
return fmt.Errorf("%s: %w: %s", name, err, strings.TrimSpace(string(out)))
}
return nil
}
type Options struct {
RunDir string
Fetcher Fetcher
Runner Runner
}
func Prepare(ctx context.Context, p *topology.Plan, o Options) ([]render.Node, error) {
if !filepath.IsAbs(o.RunDir) {
return nil, fmt.Errorf("run dir %q must be an absolute path", o.RunDir)
}
if err := os.MkdirAll(o.RunDir, 0o700); err != nil {
return nil, err
}
images := map[string]string{}
for _, n := range p.Nodes {
if _, ok := images[n.Image]; ok {
continue
}
img, ok := imageNamed(p, n.Image)
if !ok {
return nil, fmt.Errorf("node %s: image %q is not declared", n.Name, n.Image)
}
base, err := o.Fetcher.Image(ctx, img)
if err != nil {
return nil, err
}
images[n.Image] = base
}
key, err := EnsureKey(ctx, o.Runner, o.RunDir)
if err != nil {
return nil, err
}
nodes, err := render.Render(p, render.Options{RunDir: o.RunDir, AuthorizedKeys: []string{key}})
if err != nil {
return nil, err
}
for i, n := range nodes {
if err := Stage(ctx, o.Runner, n, images[p.Nodes[i].Image]); err != nil {
return nil, fmt.Errorf("node %s: %w", n.Name, err)
}
}
return nodes, nil
}
func EnsureKey(ctx context.Context, r Runner, dir string) (string, error) {
private := filepath.Join(dir, KeyFile)
if _, err := os.Stat(private); errors.Is(err, os.ErrNotExist) {
if err := r.Run(ctx, "ssh-keygen", "-q", "-t", "ed25519", "-N", "", "-C", KeyLabel, "-f", private); err != nil {
return "", err
}
} else if err != nil {
return "", err
}
data, err := os.ReadFile(private + ".pub")
if err != nil {
return "", err
}
key := strings.TrimSpace(string(data))
if key == "" || strings.ContainsAny(key, "\r\n") {
return "", fmt.Errorf("%s.pub: not a single public key", private)
}
return key, nil
}
func WriteFiles(n render.Node) error {
if err := os.MkdirAll(n.Dir, 0o700); err != nil {
return err
}
files := map[string][]byte{
ArgsFile: []byte(strings.Join(n.QEMU, "\n") + "\n"),
"meta-data": n.MetaData,
"user-data": n.UserData,
"network-config": n.NetworkConfig,
}
for name, content := range files {
if err := os.WriteFile(filepath.Join(n.Dir, name), content, 0o600); err != nil {
return err
}
}
return nil
}
func Stage(ctx context.Context, r Runner, n render.Node, base string) error {
if !filepath.IsAbs(base) {
return fmt.Errorf("base image %q must be an absolute path", base)
}
if err := WriteFiles(n); err != nil {
return err
}
disk := filepath.Join(n.Dir, render.DiskFile)
seed := filepath.Join(n.Dir, render.SeedFile)
if err := r.Run(ctx, "qemu-img", "create", "-q", "-f", "qcow2", "-F", "qcow2", "-b", base, disk, DiskSize); err != nil {
return err
}
args := []string{"-quiet", "-output", seed, "-volid", SeedLabel, "-joliet", "-rock"}
for _, f := range SeedFiles {
args = append(args, filepath.Join(n.Dir, f))
}
return r.Run(ctx, "genisoimage", args...)
}
func imageNamed(p *topology.Plan, name string) (topology.Image, bool) {
for _, i := range p.Images {
if i.Name == name {
return i, true
}
}
return topology.Image{}, false
}

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@ -0,0 +1,317 @@
package provision
import (
"context"
"errors"
"os"
"path/filepath"
"reflect"
"strings"
"testing"
"go.yaml.in/yaml/v3"
"git.g3e.fr/syonad/two/internal/lab/render"
"git.g3e.fr/syonad/two/internal/lab/topology"
)
const generatedKey = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIFG/JMmjfko96WkJV8DiL6rip/H/q/R++y8s27Z+Cj6O two-lab"
type fakeRunner struct {
calls [][]string
fail string
}
func (f *fakeRunner) Run(_ context.Context, name string, args ...string) error {
f.calls = append(f.calls, append([]string{name}, args...))
if name == f.fail {
return errors.New(name + " failed")
}
if name == "ssh-keygen" {
private := args[len(args)-1]
if err := os.WriteFile(private, []byte("private"), 0o600); err != nil {
return err
}
return os.WriteFile(private+".pub", []byte(generatedKey+"\n"), 0o644)
}
return nil
}
func (f *fakeRunner) commands(name string) [][]string {
var out [][]string
for _, c := range f.calls {
if c[0] == name {
out = append(out, c)
}
}
return out
}
func labPlan(t *testing.T, m *mirror) *topology.Plan {
t.Helper()
img := m.image()
doc := `name: evpn-2hv
images:
debian12:
url: ` + img.URL + `
sums: ` + img.Sums + `
segments:
underlay: { switch: sw1, cidr: 10.250.0.0/24, mtu: 9000 }
nodes:
sw1: { role: switch, image: debian12, cpus: 2, memory: 1024 }
rr1: { role: rr, image: debian12, cpus: 1, memory: 1024, segments: [underlay] }
hv1: { role: hypervisor, image: debian12, cpus: 4, memory: 16384, segments: [underlay] }
hv2: { role: hypervisor, image: debian12, cpus: 4, memory: 16384, segments: [underlay] }
`
topo, err := topology.Parse([]byte(doc))
if err != nil {
t.Fatalf("Parse: %v", err)
}
p, err := topology.Compute(topo)
if err != nil {
t.Fatalf("Compute: %v", err)
}
return p
}
func prepare(t *testing.T, runner *fakeRunner) (string, string, *mirror, []render.Node, error) {
t.Helper()
m := newMirror(t)
publish(m, []byte("qcow2 image"))
root := t.TempDir()
run := filepath.Join(root, "run")
cache := filepath.Join(root, "cache")
nodes, err := Prepare(context.Background(), labPlan(t, m), Options{
RunDir: run,
Fetcher: Fetcher{Client: m.server.Client(), CacheDir: cache},
Runner: runner,
})
return run, cache, m, nodes, err
}
func TestPrepare_StagesEveryNode(t *testing.T) {
runner := &fakeRunner{}
run, cache, _, nodes, err := prepare(t, runner)
if err != nil {
t.Fatalf("Prepare: %v", err)
}
base := filepath.Join(cache, "debian12", "debian-12-generic-amd64.qcow2")
want := [][]string{
{"ssh-keygen", "-q", "-t", "ed25519", "-N", "", "-C", "two-lab", "-f", filepath.Join(run, "lab_ed25519")},
}
for _, n := range []string{"sw1", "rr1", "hv1", "hv2"} {
dir := filepath.Join(run, n)
want = append(want,
[]string{"qemu-img", "create", "-q", "-f", "qcow2", "-F", "qcow2", "-b", base, filepath.Join(dir, "disk.qcow2"), "20G"},
[]string{"genisoimage", "-quiet", "-output", filepath.Join(dir, "seed.iso"), "-volid", "cidata", "-joliet", "-rock",
filepath.Join(dir, "user-data"), filepath.Join(dir, "meta-data"), filepath.Join(dir, "network-config")},
)
}
if !reflect.DeepEqual(runner.calls, want) {
t.Errorf("commands:\n got %q\nwant %q", runner.calls, want)
}
var names []string
for _, n := range nodes {
names = append(names, n.Name)
}
if !reflect.DeepEqual(names, []string{"sw1", "rr1", "hv1", "hv2"}) {
t.Errorf("nodes = %v", names)
}
if info, err := os.Stat(run); err != nil || info.Mode().Perm() != 0o700 {
t.Errorf("run dir mode = %v, %v", info.Mode().Perm(), err)
}
}
func TestPrepare_DownloadsASharedImageOnce(t *testing.T) {
_, _, m, _, err := prepare(t, &fakeRunner{})
if err != nil {
t.Fatalf("Prepare: %v", err)
}
if n := m.count("/bookworm/latest/" + imageName); n != 1 {
t.Errorf("image downloaded %d times for four nodes, want 1", n)
}
if n := m.count("/bookworm/latest/SHA512SUMS"); n != 1 {
t.Errorf("sums read %d times for four nodes, want 1", n)
}
}
func TestPrepare_TheGeneratedKeyIsTheOnlyAuthorizedKey(t *testing.T) {
_, _, _, nodes, err := prepare(t, &fakeRunner{})
if err != nil {
t.Fatalf("Prepare: %v", err)
}
for _, n := range nodes {
data, err := os.ReadFile(filepath.Join(n.Dir, "user-data"))
if err != nil {
t.Fatal(err)
}
var cfg struct {
Keys []string `yaml:"ssh_authorized_keys"`
}
if err := yaml.Unmarshal(data, &cfg); err != nil {
t.Fatalf("%s user-data: %v", n.Name, err)
}
if !reflect.DeepEqual(cfg.Keys, []string{generatedKey}) {
t.Errorf("%s authorized keys = %q, want only the generated key", n.Name, cfg.Keys)
}
}
}
func TestPrepare_WritesTheRenderedFilesPrivately(t *testing.T) {
run, _, _, nodes, err := prepare(t, &fakeRunner{})
if err != nil {
t.Fatalf("Prepare: %v", err)
}
hv1 := filepath.Join(run, "hv1")
if nodes[2].Dir != hv1 {
t.Fatalf("hv1 dir = %s, want %s", nodes[2].Dir, hv1)
}
for _, f := range []string{"qemu.args", "user-data", "meta-data", "network-config"} {
info, err := os.Stat(filepath.Join(hv1, f))
if err != nil || info.Mode().Perm() != 0o600 {
t.Errorf("%s mode = %v, %v", f, info.Mode().Perm(), err)
}
}
args, err := os.ReadFile(filepath.Join(hv1, "qemu.args"))
if err != nil || !strings.HasPrefix(string(args), "-name\nhv1\n") || !strings.HasSuffix(string(args), "\n") {
t.Errorf("qemu.args = %q, %v", args, err)
}
}
func TestPrepare_StopsAtTheFirstFailedCommand(t *testing.T) {
runner := &fakeRunner{fail: "qemu-img"}
_, _, _, _, err := prepare(t, runner)
if err == nil || !strings.Contains(err.Error(), "node sw1: qemu-img failed") {
t.Errorf("error = %v", err)
}
if n := len(runner.commands("genisoimage")); n != 0 {
t.Errorf("genisoimage ran %d times after qemu-img failed", n)
}
}
func TestPrepare_StopsBeforeAnyCommandWhenTheImageIsWrong(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
m.put("/bookworm/latest/"+imageName, []byte("tampered"))
runner := &fakeRunner{}
root := t.TempDir()
_, err := Prepare(context.Background(), labPlan(t, m), Options{
RunDir: filepath.Join(root, "run"),
Fetcher: Fetcher{Client: m.server.Client(), CacheDir: filepath.Join(root, "cache")},
Runner: runner,
})
if err == nil || !strings.Contains(err.Error(), "sha512") {
t.Errorf("error = %v", err)
}
if len(runner.calls) != 0 {
t.Errorf("commands ran after a bad image: %q", runner.calls)
}
}
func TestPrepare_RefusesARelativeRunDir(t *testing.T) {
m := newMirror(t)
publish(m, []byte("qcow2 image"))
runner := &fakeRunner{}
_, err := Prepare(context.Background(), labPlan(t, m), Options{
RunDir: "run",
Fetcher: Fetcher{Client: m.server.Client(), CacheDir: t.TempDir()},
Runner: runner,
})
if err == nil || !strings.Contains(err.Error(), `run dir "run" must be an absolute path`) {
t.Errorf("error = %v", err)
}
if n := m.count("/bookworm/latest/SHA512SUMS"); n != 0 {
t.Errorf("sums read %d times before the run dir was checked", n)
}
}
func TestPrepare_RefusesAnUndeclaredImage(t *testing.T) {
m := newMirror(t)
p := labPlan(t, m)
p.Images = nil
_, err := Prepare(context.Background(), p, Options{RunDir: t.TempDir(), Runner: &fakeRunner{}})
if err == nil || !strings.Contains(err.Error(), `node sw1: image "debian12" is not declared`) {
t.Errorf("error = %v", err)
}
}
func TestEnsureKey_GeneratesOnlyOnce(t *testing.T) {
dir := t.TempDir()
runner := &fakeRunner{}
for i := 0; i < 2; i++ {
key, err := EnsureKey(context.Background(), runner, dir)
if err != nil || key != generatedKey {
t.Fatalf("EnsureKey #%d = %q, %v", i+1, key, err)
}
}
if n := len(runner.commands("ssh-keygen")); n != 1 {
t.Errorf("ssh-keygen ran %d times, want 1", n)
}
}
func TestEnsureKey_Rejections(t *testing.T) {
cases := map[string]string{
"empty": "\n",
"two keys": generatedKey + "\n" + generatedKey + "\n",
"stray break": "ssh-ed25519\rAAAA",
}
for name, pub := range cases {
t.Run(name, func(t *testing.T) {
dir := t.TempDir()
if err := os.WriteFile(filepath.Join(dir, "lab_ed25519"), []byte("private"), 0o600); err != nil {
t.Fatal(err)
}
if err := os.WriteFile(filepath.Join(dir, "lab_ed25519.pub"), []byte(pub), 0o644); err != nil {
t.Fatal(err)
}
if _, err := EnsureKey(context.Background(), &fakeRunner{}, dir); err == nil || !strings.Contains(err.Error(), "not a single public key") {
t.Errorf("error = %v", err)
}
})
}
}
func TestEnsureKey_ReportsAFailedGeneration(t *testing.T) {
if _, err := EnsureKey(context.Background(), &fakeRunner{fail: "ssh-keygen"}, t.TempDir()); err == nil || !strings.Contains(err.Error(), "ssh-keygen failed") {
t.Errorf("error = %v", err)
}
}
func TestStage_RefusesARelativeBaseImage(t *testing.T) {
runner := &fakeRunner{}
err := Stage(context.Background(), runner, render.Node{Name: "hv1", Dir: t.TempDir()}, "debian.qcow2")
if err == nil || !strings.Contains(err.Error(), "must be an absolute path") {
t.Errorf("error = %v", err)
}
if len(runner.calls) != 0 {
t.Errorf("commands ran: %q", runner.calls)
}
}
func TestExecRunner_ReportsTheCommandOutput(t *testing.T) {
err := ExecRunner{}.Run(context.Background(), "sh", "-c", "echo boom >&2; exit 3")
if err == nil || !strings.Contains(err.Error(), "sh: exit status 3: boom") {
t.Errorf("error = %v", err)
}
if err := (ExecRunner{}).Run(context.Background(), "true"); err != nil {
t.Errorf("true: %v", err)
}
}
func TestEnsureKey_WithTheRealSSHKeygen(t *testing.T) {
dir := t.TempDir()
key, err := EnsureKey(context.Background(), ExecRunner{}, dir)
if err != nil {
t.Fatalf("EnsureKey: %v", err)
}
if !strings.HasPrefix(key, "ssh-ed25519 ") || !strings.HasSuffix(key, " two-lab") {
t.Errorf("key = %q", key)
}
info, err := os.Stat(filepath.Join(dir, "lab_ed25519"))
if err != nil || info.Mode().Perm() != 0o600 {
t.Errorf("private key mode = %v, %v", info.Mode().Perm(), err)
}
}

View file

@ -18,6 +18,7 @@ const (
type Plan struct { type Plan struct {
Name string Name string
Images []Image
Segments []SegmentPlan Segments []SegmentPlan
Nodes []NodePlan Nodes []NodePlan
Cables []Cable Cables []Cable
@ -62,7 +63,7 @@ func Compute(t *Topology) (*Plan, error) {
return nil, err return nil, err
} }
p := &Plan{Name: t.Name} p := &Plan{Name: t.Name, Images: append([]Image(nil), t.Images...)}
for i, n := range t.Nodes { for i, n := range t.Nodes {
p.Nodes = append(p.Nodes, NodePlan{ p.Nodes = append(p.Nodes, NodePlan{
Name: n.Name, Name: n.Name,

View file

@ -107,6 +107,14 @@ func TestCompute_TwoHypervisorsPlan(t *testing.T) {
} }
} }
func TestCompute_CarriesTheDeclaredImages(t *testing.T) {
p := compute(t, twoHypervisors)
want := []Image{{Name: "deb", URL: "https://example.invalid/deb.qcow2", Sums: "https://example.invalid/SHA512SUMS"}}
if !reflect.DeepEqual(p.Images, want) {
t.Errorf("images = %+v, want %+v", p.Images, want)
}
}
func TestCompute_IsStableAcrossRuns(t *testing.T) { func TestCompute_IsStableAcrossRuns(t *testing.T) {
first := compute(t, twoHypervisors) first := compute(t, twoHypervisors)
for i := 0; i < 20; i++ { for i := 0; i < 20; i++ {