Added files from the first prototype.

cmd/csaf_provider/controller.go

@@ -0,0 +1,399 @@
+package main
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"crypto/sha512"
+	"embed"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"hash"
+	"html/template"
+	"io"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/ProtonMail/gopenpgp/v2/crypto"
+
+	"github.com/intevation/csaf_trusted/csaf"
+)
+
+const dateFormat = time.RFC3339
+
+//go:embed tmpl
+var tmplFS embed.FS
+
+type controller struct {
+	cfg  *config
+	tmpl *template.Template
+}
+
+func newController(cfg *config) (*controller, error) {
+
+	c := controller{cfg: cfg}
+	var err error
+
+	if c.tmpl, err = template.ParseFS(tmplFS, "tmpl/*.html"); err != nil {
+		return nil, err
+	}
+
+	return &c, nil
+}
+
+func (c *controller) bind(pim *pathInfoMux) {
+	pim.handleFunc("/", c.index)
+	pim.handleFunc("/upload", c.upload)
+	pim.handleFunc("/create", c.create)
+}
+
+func (c *controller) render(rw http.ResponseWriter, tmpl string, arg interface{}) {
+	rw.Header().Set("Content-type", "text/html; charset=utf-8")
+	if err := c.tmpl.ExecuteTemplate(rw, tmpl, arg); err != nil {
+		log.Printf("warn: %v\n", err)
+	}
+}
+
+func (c *controller) failed(rw http.ResponseWriter, tmpl string, err error) {
+	rw.Header().Set("Content-type", "text/html; charset=utf-8")
+	result := map[string]interface{}{"Error": err}
+	if err := c.tmpl.ExecuteTemplate(rw, tmpl, result); err != nil {
+		log.Printf("warn: %v\n", err)
+	}
+}
+
+func (c *controller) index(rw http.ResponseWriter, r *http.Request) {
+	c.render(rw, "index.html", map[string]interface{}{
+		"Config": c.cfg,
+	})
+}
+
+func (c *controller) create(rw http.ResponseWriter, r *http.Request) {
+	if err := ensureFolders(c.cfg); err != nil {
+		c.failed(rw, "create.html", err)
+		return
+	}
+	c.render(rw, "create.html", nil)
+}
+
+func (c *controller) tlpParam(r *http.Request) (tlp, error) {
+	t := tlp(strings.ToLower(r.FormValue("tlp")))
+	for _, x := range c.cfg.TLPs {
+		if x == t {
+			return t, nil
+		}
+	}
+	return "", fmt.Errorf("unsupported TLP type '%s'", t)
+}
+
+func cleanFileName(s string) string {
+	s = strings.ReplaceAll(s, `/`, ``)
+	s = strings.ReplaceAll(s, `\`, ``)
+	r := regexp.MustCompile(`\.{2,}`)
+	s = r.ReplaceAllString(s, `.`)
+	return s
+}
+
+func loadCSAF(r *http.Request) (string, []byte, error) {
+	file, handler, err := r.FormFile("csaf")
+	if err != nil {
+		return "", nil, err
+	}
+	defer file.Close()
+
+	var buf bytes.Buffer
+	lr := io.LimitReader(file, 10*1024*1024)
+	if _, err := io.Copy(&buf, lr); err != nil {
+		return "", nil, err
+	}
+	return cleanFileName(handler.Filename), buf.Bytes(), nil
+}
+
+func writeHash(fname, name string, h hash.Hash, data []byte) error {
+
+	if _, err := io.Copy(h, bytes.NewReader(data)); err != nil {
+		return err
+	}
+
+	f, err := os.Create(fname)
+	if err != nil {
+		return err
+	}
+	fmt.Fprintf(f, "%x %s\n", h.Sum(nil), name)
+	return f.Close()
+}
+
+func (c *controller) loadCryptoKey() (*crypto.Key, error) {
+	f, err := os.Open(c.cfg.Key)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	return crypto.NewKeyFromArmoredReader(f)
+}
+
+func (c *controller) handleSignature(r *http.Request, data []byte) (string, string, error) {
+
+	// Either way ... we need the key.
+	key, err := c.loadCryptoKey()
+	if err != nil {
+		return "", "", err
+	}
+
+	fingerprint := key.GetFingerprint()
+
+	// Was the signature given via request?
+	if c.cfg.UploadSignature {
+		sigText := r.FormValue("signature")
+		if sigText == "" {
+			return "", "", errors.New("missing signature in request")
+		}
+
+		pgpSig, err := crypto.NewPGPSignatureFromArmored(sigText)
+		if err != nil {
+			return "", "", err
+		}
+
+		// Use as public key
+		signRing, err := crypto.NewKeyRing(key)
+		if err != nil {
+			return "", "", err
+		}
+
+		if err := signRing.VerifyDetached(
+			crypto.NewPlainMessage(data),
+			pgpSig, crypto.GetUnixTime(),
+		); err != nil {
+			return "", "", err
+		}
+
+		return sigText, fingerprint, nil
+	}
+
+	// Sign ourself
+
+	if passwd := r.FormValue("passphrase"); passwd != "" {
+		if key, err = key.Unlock([]byte(passwd)); err != nil {
+			return "", "", err
+		}
+	}
+
+	// Use as private key
+	signRing, err := crypto.NewKeyRing(key)
+	if err != nil {
+		return "", "", err
+	}
+
+	sig, err := signRing.SignDetached(crypto.NewPlainMessage(data))
+	if err != nil {
+		return "", "", err
+	}
+
+	armored, err := sig.GetArmored()
+	return armored, fingerprint, err
+}
+
+func (c *controller) upload(rw http.ResponseWriter, r *http.Request) {
+
+	newCSAF, data, err := loadCSAF(r)
+	if err != nil {
+		c.failed(rw, "upload.html", err)
+		return
+	}
+
+	var content interface{}
+	if err := json.Unmarshal(data, &content); err != nil {
+		c.failed(rw, "upload.html", err)
+		return
+	}
+
+	ex, err := newExtraction(content)
+	if err != nil {
+		c.failed(rw, "upload.html", err)
+		return
+	}
+
+	t, err := c.tlpParam(r)
+	if err != nil {
+		c.failed(rw, "upload.html", err)
+		return
+	}
+
+	// Extract real TLP from document.
+	if t == tlpCSAF {
+		if t = tlp(strings.ToLower(ex.tlpLabel)); !t.valid() || t == tlpCSAF {
+			c.failed(
+				rw, "upload.html", fmt.Errorf("not a valid TL: %s", ex.tlpLabel))
+			return
+		}
+	}
+
+	armored, fingerprint, err := c.handleSignature(r, data)
+	if err != nil {
+		c.failed(rw, "upload.html", err)
+		return
+	}
+
+	if err := c.doTransaction(t, func(folder string, pmd *csaf.ProviderMetadata) error {
+
+		year := strconv.Itoa(ex.currentReleaseDate.Year())
+
+		subDir := filepath.Join(folder, year)
+
+		// Create folder if it does not exists.
+		if _, err := os.Stat(subDir); err != nil {
+			if os.IsNotExist(err) {
+				if err := os.Mkdir(subDir, 0755); err != nil {
+					return err
+				}
+			} else {
+				return err
+			}
+		}
+
+		fname := filepath.Join(subDir, newCSAF)
+
+		// Write the file itself.
+		if err := ioutil.WriteFile(fname, data, 0644); err != nil {
+			return err
+		}
+
+		// Write SHA256 sum.
+		if err := writeHash(fname+".sha256", newCSAF, sha256.New(), data); err != nil {
+			return err
+		}
+
+		// Write SHA512 sum.
+		if err := writeHash(fname+".sha512", newCSAF, sha512.New(), data); err != nil {
+			return err
+		}
+
+		// Write signature.
+		if err := ioutil.WriteFile(fname+".asc", []byte(armored), 0644); err != nil {
+			return err
+		}
+
+		if err := updateIndices(
+			folder, filepath.Join(year, newCSAF),
+			ex.currentReleaseDate,
+		); err != nil {
+			return err
+		}
+
+		// Take over publisher
+		// TODO: Check for conflicts.
+		pmd.Publisher = ex.publisher
+
+		pmd.SetPGP(fingerprint, c.cfg.GetPGPURL(fingerprint))
+
+		return nil
+	}); err != nil {
+		c.failed(rw, "upload.html", err)
+		return
+	}
+
+	result := map[string]interface{}{
+		"Name":        newCSAF,
+		"ReleaseDate": ex.currentReleaseDate.Format(dateFormat),
+	}
+
+	c.render(rw, "upload.html", result)
+}
+
+func (c *controller) doTransaction(
+	t tlp,
+	fn func(string, *csaf.ProviderMetadata) error,
+) error {
+
+	wellknown := filepath.Join(c.cfg.Web, ".well-known", "csaf")
+
+	metadata := filepath.Join(wellknown, "provider-metadata.json")
+
+	pmd, err := func() (*csaf.ProviderMetadata, error) {
+		f, err := os.Open(metadata)
+		if err != nil {
+			if os.IsNotExist(err) {
+				return csaf.NewProviderMetadata(
+					c.cfg.Domain + "/.wellknown/csaf/provider-metadata.json"), nil
+			}
+			return nil, err
+		}
+		defer f.Close()
+		return csaf.LoadProviderMetadata(f)
+	}()
+
+	if err != nil {
+		return err
+	}
+
+	webTLP := filepath.Join(wellknown, string(t))
+
+	oldDir, err := filepath.EvalSymlinks(webTLP)
+	if err != nil {
+		return err
+	}
+
+	folderTLP := filepath.Join(c.cfg.Folder, string(t))
+
+	newDir, err := mkUniqDir(folderTLP)
+	if err != nil {
+		return err
+	}
+
+	// Copy old content into new.
+	if err := deepCopy(newDir, oldDir); err != nil {
+		os.RemoveAll(newDir)
+		return err
+	}
+
+	// Work with new folder.
+	if err := fn(newDir, pmd); err != nil {
+		os.RemoveAll(newDir)
+		return err
+	}
+
+	// Write back provider metadata.
+	newMetaName, newMetaFile, err := mkUniqFile(metadata)
+	if err != nil {
+		os.RemoveAll(newDir)
+		return err
+	}
+
+	if err := pmd.Save(newMetaFile); err != nil {
+		newMetaFile.Close()
+		os.Remove(newMetaName)
+		os.RemoveAll(newDir)
+		return err
+	}
+
+	if err := newMetaFile.Close(); err != nil {
+		os.Remove(newMetaName)
+		os.RemoveAll(newDir)
+		return err
+	}
+
+	if err := os.Rename(newMetaName, metadata); err != nil {
+		os.RemoveAll(newDir)
+		return err
+	}
+
+	// Switch directories.
+	symlink := filepath.Join(newDir, string(t))
+	if err := os.Symlink(newDir, symlink); err != nil {
+		os.RemoveAll(newDir)
+		return err
+	}
+	if err := os.Rename(symlink, webTLP); err != nil {
+		os.RemoveAll(newDir)
+		return err
+	}
+
+	return os.RemoveAll(oldDir)
+}