node-installer: initialize

go.work

@@ -3,4 +3,5 @@ go 1.21
 use (
 	.
 	./service-mesh
+	./node-installer
 )

node-installer/README.md

@@ -0,0 +1,44 @@
+# Contrast node installer
+
+This program runs as a daemonset on every CC-enabled node of a Kubernetes cluster.
+It expects the host filesystem of the node to be mounted under `/host`.
+On start, it will read a configuration file under `$CONFIG_DIR/contrast-node-install.json` and install binary artifacts on the host filesystem according to the configuration.
+After installing binary artifacts, it installs and patches configuration files for the Contrast runtime class `contrast-cc-isolation` and restarts containerd.
+
+## Configuration
+
+By default, the installer ships with a config file under `/config/contrast-node-install.json`, which takes binary artifacts from the container image.
+If desired, you can replace the configuration using a Kubernetes configmap by mounting it into the container.
+
+- `files`: List of files to be installed.
+- `files[*].url`: Source of the file's content. Use `http://` or `https://` to download it or `file://` to copy a file from the container image.
+- `files[*].path`: Target location of the file on the host filesystem.
+- `files[*].integrity`: Expected Subresource Integrity (SRI) digest of the file. Only required if url starts with `http://` or `https://`.
+
+Consider the following example:
+
+```json
+{
+    "files": [
+        {
+            "url": "https://cdn.confidential.cloud/contrast/node-components/2024-03-13/kata-containers.img",
+            "path": "/opt/edgeless/share/kata-containers.img",
+            "integrity": "sha256-EdFywKAU+xD0BXmmfbjV4cB6Gqbq9R9AnMWoZFCM3A0="
+        },
+        {
+            "url": "https://cdn.confidential.cloud/contrast/node-components/2024-03-13/kata-containers-igvm.img",
+            "path": "/opt/edgeless/share/kata-containers-igvm.img",
+            "integrity": "sha256-E9Ttx6f9QYwKlQonO/fl1bF2MNBoU4XG3/HHvt9Zv30="
+        },
+        {
+            "url": "https://cdn.confidential.cloud/contrast/node-components/2024-03-13/cloud-hypervisor-cvm",
+            "path": "/opt/edgeless/bin/cloud-hypervisor-snp",
+            "integrity": "sha256-coTHzd5/QLjlPQfrp9d2TJTIXKNuANTN7aNmpa8PRXo="
+        },
+        {
+            "url": "file:///opt/edgeless/bin/containerd-shim-contrast-cc-v2",
+            "path": "/opt/edgeless/bin/containerd-shim-contrast-cc-v2",
+        }
+    ]
+}
+```

node-installer/go.mod

@@ -0,0 +1,17 @@
+module github.com/edgelesssys/contrast/node-installer
+
+go 1.21
+
+require (
+	github.com/pelletier/go-toml v1.9.5
+	github.com/stretchr/testify v1.9.0
+	go.uber.org/goleak v1.3.0
+	golang.org/x/sys v0.18.0
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

node-installer/go.sum

@@ -0,0 +1,22 @@
+github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
+github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/pelletier/go-toml v1.9.5 h1:4yBQzkHv+7BHq2PQUZF3Mx0IYxG7LsP222s7Agd3ve8=
+github.com/pelletier/go-toml v1.9.5/go.mod h1:u1nR/EPcESfeI/szUZKdtJ0xRNbUoANCkoOuaOx1Y+c=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
+github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
+go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
+golang.org/x/sys v0.18.0 h1:DBdB3niSjOA/O0blCZBqDefyWNYveAYMNF1Wum0DYQ4=
+golang.org/x/sys v0.18.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

node-installer/internal/asset/fetcher.go

@@ -0,0 +1,89 @@
+package asset
+
+import (
+	"context"
+	"crypto/sha256"
+	"crypto/sha512"
+	"encoding/base64"
+	"fmt"
+	"hash"
+	"net/url"
+)
+
+// Fetcher can retrieve assets from various sources.
+// It works by delegating to a handler for the scheme of the source URI.
+type Fetcher struct {
+	handlers map[string]handler
+}
+
+// NewDefaultFetcher creates a new fetcher with default handlers.
+func NewDefaultFetcher() *Fetcher {
+	fileFetcher := NewFileFetcher()
+	httpFetcher := NewHTTPFetcher()
+	return NewFetcher(map[string]handler{
+		"file":  fileFetcher,
+		"http":  httpFetcher,
+		"https": httpFetcher,
+	})
+}
+
+// NewFetcher creates a new fetcher.
+func NewFetcher(handlers map[string]handler) *Fetcher {
+	return &Fetcher{
+		handlers: handlers,
+	}
+}
+
+// Fetch retrieves a file from a source URI.
+func (f *Fetcher) Fetch(ctx context.Context, sourceURI, destination, integrity string) (changed bool, retErr error) {
+	uri, err := url.Parse(sourceURI)
+	if err != nil {
+		return false, err
+	}
+	hasher, expectedSum, err := hashFromIntegrity(integrity)
+	if err != nil {
+		return false, err
+	}
+	schemeFetcher := f.handlers[uri.Scheme]
+	if schemeFetcher == nil {
+		return false, fmt.Errorf("no handler for scheme %s", uri.Scheme)
+	}
+	return schemeFetcher.Fetch(ctx, uri, destination, expectedSum, hasher)
+}
+
+// FetchUnchecked retrieves a file from a source URI without verifying its integrity.
+func (f *Fetcher) FetchUnchecked(ctx context.Context, sourceURI, destination string) error {
+	uri, err := url.Parse(sourceURI)
+	if err != nil {
+		return err
+	}
+	schemeFetcher := f.handlers[uri.Scheme]
+	if schemeFetcher == nil {
+		return fmt.Errorf("no handler for scheme %s", uri.Scheme)
+	}
+	return schemeFetcher.FetchUnchecked(ctx, uri, destination)
+}
+
+type handler interface {
+	Fetch(ctx context.Context, uri *url.URL, destination string, expectedSum []byte, hasher hash.Hash) (bool, error)
+	FetchUnchecked(ctx context.Context, uri *url.URL, destination string) error
+}
+
+func hashFromIntegrity(integrity string) (hash.Hash, []byte, error) {
+	var hash hash.Hash
+	switch integrity[:7] {
+	case "sha256-":
+		hash = sha256.New()
+	case "sha384-":
+		hash = sha512.New384()
+	case "sha512-":
+		hash = sha512.New()
+	default:
+		return nil, nil, fmt.Errorf("unsupported hash algorithm: %s", integrity[:7])
+	}
+	expectedSum, err := base64.StdEncoding.DecodeString(integrity[7:])
+	if err != nil {
+		return nil, nil, fmt.Errorf("decoding integrity value: %w", err)
+	}
+	return hash, expectedSum, nil
+}

node-installer/internal/asset/fetcher_test.go

@@ -0,0 +1,139 @@
+package asset
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/edgelesssys/contrast/node-installer/internal/fileop"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/goleak"
+)
+
+func TestMain(m *testing.M) {
+	goleak.VerifyTestMain(m)
+}
+
+func TestFetch(t *testing.T) {
+	sourceDir, err := os.MkdirTemp("", "fileop-test-empty")
+	require.NoError(t, err)
+	fooSource := filepath.Join(sourceDir, "foo")
+	require.NoError(t, os.WriteFile(fooSource, []byte("foo"), 0o644))
+	defer os.RemoveAll(sourceDir)
+
+	testCases := map[string]struct {
+		dstContent   []byte
+		sourceURIs   []string
+		sri          string
+		wantModified bool
+		wantErr      bool
+	}{
+		"identical": {
+			dstContent: []byte("foo"),
+			sourceURIs: []string{"file://" + fooSource, "http://example.com/foo"},
+			sri:        "sha256-LCa0a2j/xo/5m0U8HTBBNBNCLXBkg7+g+YpeiGJm564=",
+		},
+		"different": {
+			dstContent:   []byte("bar"),
+			sourceURIs:   []string{"file://" + fooSource, "http://example.com/foo"},
+			sri:          "sha256-LCa0a2j/xo/5m0U8HTBBNBNCLXBkg7+g+YpeiGJm564=",
+			wantModified: true,
+		},
+		"sri mismatch": {
+			dstContent: []byte("foo"),
+			sourceURIs: []string{"file://" + fooSource, "http://example.com/foo"},
+			sri:        "sha256-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=",
+			wantErr:    true,
+		},
+		"unchecked": {
+			dstContent:   []byte("bar"),
+			sourceURIs:   []string{"file://" + fooSource, "http://example.com/foo"},
+			wantModified: true,
+		},
+		"src not found": {
+			dstContent: []byte("foo"),
+			sourceURIs: []string{"file://this/file/is/nonexistent", "http://example.com//this/file/is/nonexistent"},
+			wantErr:    true,
+		},
+		"dst not found": {
+			sourceURIs:   []string{"file://" + fooSource, "http://example.com/foo"},
+			wantModified: true,
+		},
+	}
+	for name, tc := range testCases {
+		for _, sourceURI := range tc.sourceURIs {
+			t.Run(name+"_"+sourceURI, func(t *testing.T) {
+				assert := assert.New(t)
+				require := require.New(t)
+
+				emptyDir, err := os.MkdirTemp("", "fileop-test-empty")
+				require.NoError(err)
+				defer os.RemoveAll(emptyDir)
+				dst := filepath.Join(emptyDir, "dst")
+				if tc.dstContent != nil {
+					require.NoError(os.WriteFile(dst, tc.dstContent, 0o644))
+					defer os.Remove(dst)
+				}
+				httpResponses := map[string][]byte{
+					"/foo": []byte("foo"),
+				}
+				fetcher := NewFetcher(map[string]handler{
+					"file": NewFileFetcher(),
+					"http": newFakeHTTPFetcher(httpResponses),
+				})
+				var modified bool
+				var fetchErr error
+				if tc.sri != "" {
+					modified, fetchErr = fetcher.Fetch(context.Background(), sourceURI, dst, tc.sri)
+				} else {
+					fetchErr = fetcher.FetchUnchecked(context.Background(), sourceURI, dst)
+					modified = true // FetchUnchecked always modifies the file
+				}
+				if tc.wantErr {
+					require.Error(fetchErr)
+					return
+				}
+				require.NoError(fetchErr)
+				assert.Equal(tc.wantModified, modified)
+				got, err := os.ReadFile(dst)
+				require.NoError(err)
+				assert.Equal([]byte("foo"), got)
+			})
+		}
+	}
+}
+
+func newFakeHTTPFetcher(responses map[string][]byte) *HTTPFetcher {
+	hClient := http.Client{
+		Transport: &fakeRoundTripper{store: responses},
+	}
+
+	return &HTTPFetcher{
+		client: &hClient,
+		mover:  fileop.NewDefault(),
+	}
+}
+
+type fakeRoundTripper struct {
+	store map[string][]byte
+}
+
+func (f *fakeRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	path := req.URL.Path
+	body, ok := f.store[path]
+	if !ok {
+		return &http.Response{
+			StatusCode: http.StatusNotFound,
+			Body:       io.NopCloser(bytes.NewReader([]byte("not found"))),
+		}, nil
+	}
+	return &http.Response{
+		StatusCode: http.StatusOK,
+		Body:       io.NopCloser(bytes.NewReader(body)),
+	}, nil
+}

node-installer/internal/asset/file.go

@@ -0,0 +1,65 @@
+package asset
+
+import (
+	"context"
+	"fmt"
+	"hash"
+	"io"
+	"net/url"
+	"os"
+	"slices"
+
+	"github.com/edgelesssys/contrast/node-installer/internal/fileop"
+)
+
+// FileFetcher is a Fetcher that retrieves assets from a file.
+// It handles the "file" scheme.
+type FileFetcher struct {
+	copier copier
+}
+
+// NewFileFetcher creates a new file fetcher.
+func NewFileFetcher() *FileFetcher {
+	return &FileFetcher{copier: fileop.NewDefault()}
+}
+
+// Fetch retrieves a file from the local filesystem.
+func (f *FileFetcher) Fetch(_ context.Context, uri *url.URL, destination string, expectedSum []byte, hasher hash.Hash) (bool, error) {
+	if uri.Scheme != "file" {
+		return false, fmt.Errorf("file fetcher does not support scheme %s", uri.Scheme)
+	}
+	sourceFile, err := os.Open(uri.Path)
+	if err != nil {
+		return false, fmt.Errorf("opening file: %w", err)
+	}
+	defer sourceFile.Close()
+
+	if _, err := io.Copy(hasher, sourceFile); err != nil {
+		return false, fmt.Errorf("hashing file: %w", err)
+	}
+	if err := sourceFile.Close(); err != nil {
+		return false, fmt.Errorf("closing file: %w", err)
+	}
+	actualSum := hasher.Sum(nil)
+	if !slices.Equal(actualSum, expectedSum) {
+		return false, fmt.Errorf("file hash mismatch: expected %x, got %x", expectedSum, actualSum)
+	}
+	changed, err := f.copier.CopyOnDiff(uri.Path, destination)
+	if err != nil {
+		return false, fmt.Errorf("copying file: %w", err)
+	}
+	return changed, nil
+}
+
+// FetchUnchecked retrieves a file from the local filesystem without verifying its integrity.
+func (f *FileFetcher) FetchUnchecked(_ context.Context, uri *url.URL, destination string) error {
+	if uri.Scheme != "file" {
+		return fmt.Errorf("file fetcher does not support scheme %s", uri.Scheme)
+	}
+	_, err := f.copier.CopyOnDiff(uri.Path, destination)
+	return err
+}
+
+type copier interface {
+	CopyOnDiff(src, dst string) (bool, error)
+}