refactor: rename internal/fs package to internal/common as it contains various stuff

descriptions.go

@@ -6,7 +6,7 @@ import (
 	"path/filepath"
 
 	"github.com/go-errors/errors"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 )
 
 // This file contains data types for scheme managers, issuers, credential types
@@ -199,7 +199,7 @@ func (ct *CredentialType) SchemeManagerIdentifier() SchemeManagerIdentifier {
 
 func (ct *CredentialType) Logo(conf *Configuration) string {
 	path := filepath.Join(conf.Path, ct.SchemeManagerID, ct.IssuerID, "Issues", ct.ID, "logo.png")
-	exists, err := fs.PathExists(path)
+	exists, err := common.PathExists(path)
 	if err != nil || !exists {
 		return ""
 	}

internal/fs/fs.go → internal/common/common.go

-package fs
+package common
 
 import (
 	"crypto/rand"

internal/servercore/sessions.go

@@ -9,7 +9,7 @@ import (
 	"github.com/privacybydesign/gabi"
 	"github.com/privacybydesign/gabi/big"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/privacybydesign/irmago/server"
 
 	"github.com/sirupsen/logrus"
@@ -176,7 +176,7 @@ func (s *Server) newSession(action irma.Action, request irma.RequestorRequest) *
 	}
 
 	s.conf.Logger.WithFields(logrus.Fields{"session": ses.token}).Debug("New session started")
-	nonce := fs.RandomBigInt(new(big.Int).Lsh(big.NewInt(1), gabi.DefaultSystemParameters[2048].Lstatzk))
+	nonce := common.RandomBigInt(new(big.Int).Lsh(big.NewInt(1), gabi.DefaultSystemParameters[2048].Lstatzk))
 	ses.request.Base().Nonce = nonce
 	ses.request.Base().Context = one
 	s.sessions.add(ses)

internal/sessiontest/session_test.go

@@ -10,7 +10,7 @@ import (
 	"time"
 
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/privacybydesign/irmago/internal/test"
 	"github.com/privacybydesign/irmago/irmaclient"
 	"github.com/privacybydesign/irmago/server"
@@ -445,13 +445,13 @@ func TestDownloadSchemeManager(t *testing.T) {
 	require.Contains(t, client.Configuration.CredentialTypes, irma.NewCredentialTypeIdentifier("irma-demo.RU.studentCard"))
 
 	basepath := filepath.Join(handler.storage, "client", "irma_configuration", "irma-demo")
-	exists, err := fs.PathExists(filepath.Join(basepath, "description.xml"))
+	exists, err := common.PathExists(filepath.Join(basepath, "description.xml"))
 	require.NoError(t, err)
 	require.True(t, exists)
-	exists, err = fs.PathExists(filepath.Join(basepath, "RU", "description.xml"))
+	exists, err = common.PathExists(filepath.Join(basepath, "RU", "description.xml"))
 	require.NoError(t, err)
 	require.True(t, exists)
-	exists, err = fs.PathExists(filepath.Join(basepath, "RU", "Issues", "studentCard", "description.xml"))
+	exists, err = common.PathExists(filepath.Join(basepath, "RU", "Issues", "studentCard", "description.xml"))
 	require.NoError(t, err)
 	require.True(t, exists)
 }

internal/test/testdata.go

@@ -13,7 +13,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/stretchr/testify/require"
 )
 
@@ -74,7 +74,7 @@ func FindTestdataFolder(t *testing.T) string {
 	path := "testdata"
 
 	for i := 0; i < 3; i++ {
-		exists, err := fs.PathExists(path)
+		exists, err := common.PathExists(path)
 		checkError(t, err)
 		if exists {
 			return path
@@ -103,14 +103,14 @@ func ClearAllTestStorage() {
 func CreateTestStorage(t *testing.T) string {
 	tmp, err := ioutil.TempDir("", "irmatest")
 	require.NoError(t, err)
-	checkError(t, fs.EnsureDirectoryExists(filepath.Join(tmp, "client")))
+	checkError(t, common.EnsureDirectoryExists(filepath.Join(tmp, "client")))
 	return tmp
 }
 
 func SetupTestStorage(t *testing.T) string {
 	storage := CreateTestStorage(t)
 	path := FindTestdataFolder(t)
-	err := fs.CopyDirectory(filepath.Join(path, testStorageDir), filepath.Join(storage, "client"))
+	err := common.CopyDirectory(filepath.Join(path, testStorageDir), filepath.Join(storage, "client"))
 	checkError(t, err)
 	return storage
 }

irma/cmd/download.go

@@ -8,7 +8,7 @@ import (
 
 	"github.com/go-errors/errors"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/spf13/cobra"
 )
 
@@ -24,7 +24,7 @@ var downloadCmd = &cobra.Command{
 		if len(args) == 0 {
 			path = defaultIrmaconf
 		} else {
-			if err := fs.AssertPathExists(args[0]); err == nil {
+			if err := common.AssertPathExists(args[0]); err == nil {
 				path = args[0]
 				urls = args[1:]
 			} else {
@@ -36,7 +36,7 @@ var downloadCmd = &cobra.Command{
 			if defaultIrmaconf == "" {
 				die("Failed to determine default irma_configuration path", nil)
 			}
-			if err := fs.EnsureDirectoryExists(defaultIrmaconf); err != nil {
+			if err := common.EnsureDirectoryExists(defaultIrmaconf); err != nil {
 				die("Failed to create irma_configuration directory", err)
 			}
 			fmt.Println("No irma_configuration path specified, using " + defaultIrmaconf)
@@ -48,7 +48,7 @@ var downloadCmd = &cobra.Command{
 }
 
 func downloadSchemeManager(dest string, urls []string) error {
-	exists, err := fs.PathExists(dest)
+	exists, err := common.PathExists(dest)
 	if err != nil {
 		return errors.Errorf("Could not check path existence: %s", err.Error())
 	}
@@ -72,7 +72,7 @@ func downloadSchemeManager(dest string, urls []string) error {
 		normalizedUrls = append(normalizedUrls, u)
 		urlparts := strings.Split(u, "/")
 		managerName := urlparts[len(urlparts)-1]
-		if err = fs.AssertPathNotExists(filepath.Join(dest, managerName)); err != nil {
+		if err = common.AssertPathNotExists(filepath.Join(dest, managerName)); err != nil {
 			return errors.Errorf("Scheme manager %s already exists", managerName)
 		}
 	}

irma/cmd/issuer-keygen.go

@@ -10,7 +10,7 @@ import (
 
 	"github.com/go-errors/errors"
 	"github.com/privacybydesign/gabi"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/spf13/cobra"
 )
 
@@ -79,7 +79,7 @@ IRMA applications.`,
 				return err
 			}
 		}
-		if err = fs.AssertPathExists(path); err != nil {
+		if err = common.AssertPathExists(path); err != nil {
 			return errors.WrapPrefix(err, "Nonexisting path specified", 0)
 		}
 
@@ -101,14 +101,14 @@ IRMA applications.`,
 		defaultFilename := strconv.Itoa(int(counter)) + ".xml"
 		if privkeyfile == "" {
 			keypath := filepath.Join(path, "PrivateKeys")
-			if err = fs.EnsureDirectoryExists(keypath); err != nil {
+			if err = common.EnsureDirectoryExists(keypath); err != nil {
 				return errors.WrapPrefix(err, "Failed to create"+keypath, 0)
 			}
 			privkeyfile = filepath.Join(keypath, defaultFilename)
 		}
 		if pubkeyfile == "" {
 			keypath := filepath.Join(path, "PublicKeys")
-			if err = fs.EnsureDirectoryExists(keypath); err != nil {
+			if err = common.EnsureDirectoryExists(keypath); err != nil {
 				return errors.WrapPrefix(err, "Failed to create"+keypath, 0)
 			}
 			pubkeyfile = filepath.Join(keypath, defaultFilename)

irma/cmd/keygen.go

@@ -10,7 +10,7 @@ import (
 
 	"github.com/go-errors/errors"
 	"github.com/privacybydesign/gabi/signed"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/spf13/cobra"
 )
 
@@ -30,10 +30,10 @@ var keygenCmd = &cobra.Command{
 		}
 
 		// For safety we enforce that we never overwrite a file
-		if err := fs.AssertPathNotExists(skfile); err != nil {
+		if err := common.AssertPathNotExists(skfile); err != nil {
 			return errors.Errorf("File %s already exists, not overwriting", skfile)
 		}
-		if err := fs.AssertPathNotExists(pkfile); err != nil {
+		if err := common.AssertPathNotExists(pkfile); err != nil {
 			return errors.Errorf("File %s already exists, not overwriting", pkfile)
 		}
 

irma/cmd/meta.go

@@ -10,7 +10,7 @@ import (
 	"github.com/privacybydesign/gabi"
 	"github.com/privacybydesign/gabi/big"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/spf13/cobra"
 )
 
@@ -46,7 +46,7 @@ var metaCmd = &cobra.Command{
 }
 
 func printMetadataAttr(metaint *big.Int, confpath string) error {
-	if err := fs.AssertPathExists(confpath); err != nil {
+	if err := common.AssertPathExists(confpath); err != nil {
 		return errors.WrapPrefix(err, "Cannot read irma_configuration", 0)
 	}
 	conf, err := irma.NewConfiguration(confpath, irma.ConfigurationOptions{ReadOnly: true})

irma/cmd/request.go

@@ -14,7 +14,7 @@ import (
 	"github.com/go-errors/errors"
 	"github.com/mdp/qrterminal"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/privacybydesign/irmago/server"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
@@ -55,13 +55,13 @@ func configureJWTKey(authmethod, key string) (interface{}, jwt.SigningMethod, er
 		bts    []byte
 	)
 	// If the key refers to an existing file, use contents of the file as key
-	if bts, err = fs.ReadKey("", key); err != nil {
+	if bts, err = common.ReadKey("", key); err != nil {
 		bts = []byte(key)
 	}
 	switch authmethod {
 	case "hmac":
 		jwtalg = jwt.SigningMethodHS256
-		if sk, err = fs.Base64Decode(bts); err != nil {
+		if sk, err = common.Base64Decode(bts); err != nil {
 			return nil, nil, err
 		}
 	case "rsa":

irma/cmd/sign.go

@@ -14,7 +14,7 @@ import (
 	"github.com/go-errors/errors"
 	"github.com/privacybydesign/gabi/signed"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/spf13/cobra"
 )
 
@@ -50,7 +50,7 @@ Careful: this command could fail and invalidate or destroy your scheme manager d
 			return errors.WrapPrefix(err, "Failed to read private key:", 0)
 		}
 
-		if err = fs.AssertPathExists(confpath); err != nil {
+		if err = common.AssertPathExists(confpath); err != nil {
 			return err
 		}
 
@@ -80,7 +80,7 @@ func signManager(privatekey *ecdsa.PrivateKey, confpath string, skipverification
 
 	// Traverse dir and add file hashes to index
 	var index irma.SchemeManagerIndex = make(map[string]irma.ConfigurationFileHash)
-	err := fs.WalkDir(confpath, func(path string, info os.FileInfo) error {
+	err := common.WalkDir(confpath, func(path string, info os.FileInfo) error {
 		return calculateFileHash(path, info, confpath, index)
 	})
 	if err != nil {

irma/cmd/update.go

@@ -6,7 +6,7 @@ import (
 
 	"github.com/go-errors/errors"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/spf13/cobra"
 )
 
@@ -44,7 +44,7 @@ var updateCmd = &cobra.Command{
 func updateSchemeManager(paths []string) error {
 	// Before doing anything, first check that all paths are scheme managers
 	for _, path := range paths {
-		if err := fs.AssertPathExists(filepath.Join(path, "index")); err != nil {
+		if err := common.AssertPathExists(filepath.Join(path, "index")); err != nil {
 			return errors.Errorf("%s is not a valid scheme manager (%s)", path, err.Error())
 		}
 	}

irma/cmd/verify.go

@@ -8,7 +8,7 @@ import (
 
 	"github.com/go-errors/errors"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/spf13/cobra"
 )
 
@@ -45,7 +45,7 @@ func RunVerify(path string, verbose bool) error {
 		return err
 	}
 
-	isScheme, err := fs.PathExists(filepath.Join(path, "index"))
+	isScheme, err := common.PathExists(filepath.Join(path, "index"))
 	if err != nil {
 		return err
 	}

irmaclient/client.go

@@ -13,7 +13,7 @@ import (
 	"github.com/privacybydesign/gabi/big"
 	"github.com/privacybydesign/gabi/revocation"
 	"github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/sirupsen/logrus"
 )
 
@@ -131,10 +131,10 @@ func New(
 	handler ClientHandler,
 ) (*Client, error) {
 	var err error
-	if err = fs.AssertPathExists(storagePath); err != nil {
+	if err = common.AssertPathExists(storagePath); err != nil {
 		return nil, err
 	}
-	if err = fs.AssertPathExists(irmaConfigurationPath); err != nil {
+	if err = common.AssertPathExists(irmaConfigurationPath); err != nil {
 		return nil, err
 	}
 
@@ -339,7 +339,7 @@ func (client *Client) addCredential(cred *credential) (err error) {
 
 func generateSecretKey() (*secretKey, error) {
 	return &secretKey{
-		Key: fs.RandomBigInt(new(big.Int).Lsh(big.NewInt(1), uint(gabi.DefaultSystemParameters[1024].Lm))),
+		Key: common.RandomBigInt(new(big.Int).Lsh(big.NewInt(1), uint(gabi.DefaultSystemParameters[1024].Lm))),
 	}, nil
 }
 
@@ -844,7 +844,7 @@ func (client *Client) Proofs(choice *irma.DisclosureChoice, request irma.Session
 
 // generateIssuerProofNonce generates a nonce which the issuer must use in its gabi.ProofS.
 func generateIssuerProofNonce() (*big.Int, error) {
-	return fs.RandomBigInt(new(big.Int).Lsh(big.NewInt(1), uint(gabi.DefaultSystemParameters[4096].Lstatzk))), nil
+	return common.RandomBigInt(new(big.Int).Lsh(big.NewInt(1), uint(gabi.DefaultSystemParameters[4096].Lstatzk))), nil
 }
 
 // IssuanceProofBuilders constructs a list of proof builders in the issuance protocol

irmaclient/legacy.go

@@ -8,7 +8,7 @@ import (
 	"github.com/privacybydesign/gabi"
 	"github.com/privacybydesign/gabi/revocation"
 	irma "github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 )
 
 // This file contains the legacy storage based on files. These functions are needed
@@ -36,7 +36,7 @@ func (f *fileStorage) path(p string) string {
 }
 
 func (f *fileStorage) load(dest interface{}, path string) (err error) {
-	exists, err := fs.PathExists(f.path(path))
+	exists, err := common.PathExists(f.path(path))
 	if err != nil || !exists {
 		return
 	}
@@ -58,7 +58,7 @@ func (f *fileStorage) signatureFilename(attrs *irma.AttributeList) string {
 
 func (f *fileStorage) LoadSignature(attrs *irma.AttributeList) (signature *gabi.CLSignature, witness *revocation.Witness, err error) {
 	sigpath := f.signatureFilename(attrs)
-	if err := fs.AssertPathExists(f.path(sigpath)); err != nil {
+	if err := common.AssertPathExists(f.path(sigpath)); err != nil {
 		return nil, nil, err
 	}
 	sig := &clSignatureWitness{}

irmaclient/storage.go

@@ -9,7 +9,7 @@ import (
 	"github.com/privacybydesign/gabi"
 	"github.com/privacybydesign/gabi/revocation"
 	irma "github.com/privacybydesign/irmago"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 
 	"github.com/go-errors/errors"
 	"go.etcd.io/bbolt"
@@ -55,7 +55,7 @@ func (s *storage) path(p string) string {
 // backups to iCloud/Google disabled) is the responsibility of the user.
 func (s *storage) Open() error {
 	var err error
-	if err = fs.AssertPathExists(s.storagePath); err != nil {
+	if err = common.AssertPathExists(s.storagePath); err != nil {
 		return err
 	}
 	s.db, err = bbolt.Open(s.path(databaseFile), 0600, &bbolt.Options{Timeout: 1 * time.Second})

irmaconfig.go

@@ -34,7 +34,7 @@ import (
 	"github.com/privacybydesign/gabi"
 	"github.com/privacybydesign/gabi/big"
 	"github.com/privacybydesign/gabi/signed"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/sirupsen/logrus"
 )
 
@@ -138,11 +138,11 @@ func NewConfiguration(path string, opts ConfigurationOptions) (conf *Configurati
 	}
 
 	if conf.assets != "" { // If an assets folder is specified, then it must exist
-		if err = fs.AssertPathExists(conf.assets); err != nil {
+		if err = common.AssertPathExists(conf.assets); err != nil {
 			return nil, errors.WrapPrefix(err, "Nonexistent assets folder specified", 0)
 		}
 	}
-	if err = fs.EnsureDirectoryExists(conf.Path); err != nil {
+	if err = common.EnsureDirectoryExists(conf.Path); err != nil {
 		return nil, err
 	}
 
@@ -172,7 +172,7 @@ func (conf *Configuration) ParseFolder() (err error) {
 
 	// Copy any new or updated scheme managers out of the assets into storage
 	if conf.assets != "" {
-		err = fs.IterateSubfolders(conf.assets, func(dir string, _ os.FileInfo) error {
+		err = common.IterateSubfolders(conf.assets, func(dir string, _ os.FileInfo) error {
 			scheme := NewSchemeManagerIdentifier(filepath.Base(dir))
 			uptodate, err := conf.isUpToDate(scheme)
 			if err != nil {
@@ -190,7 +190,7 @@ func (conf *Configuration) ParseFolder() (err error) {
 
 	// Parse scheme managers in storage
 	var mgrerr *SchemeManagerError
-	err = fs.IterateSubfolders(conf.Path, func(dir string, _ os.FileInfo) error {
+	err = common.IterateSubfolders(conf.Path, func(dir string, _ os.FileInfo) error {
 		manager := NewSchemeManager(filepath.Base(dir))
 		err := conf.ParseSchemeManagerFolder(dir, manager)
 		if err == nil {
@@ -464,7 +464,7 @@ func (conf *Configuration) Prune() {
 }
 
 func (conf *Configuration) parseIssuerFolders(manager *SchemeManager, path string) error {
-	return fs.IterateSubfolders(path, func(dir string, _ os.FileInfo) error {
+	return common.IterateSubfolders(path, func(dir string, _ os.FileInfo) error {
 		issuer := &Issuer{}
 		exists, err := conf.pathToDescription(manager, dir+"/description.xml", issuer)
 		if err != nil {
@@ -608,7 +608,7 @@ func (conf *Configuration) matchKeyPattern(issuerid IssuerIdentifier, pattern st
 // parse $schememanager/$issuer/Issues/*/description.xml
 func (conf *Configuration) parseCredentialsFolder(manager *SchemeManager, issuer *Issuer, path string) error {
 	var foundcred bool
-	err := fs.IterateSubfolders(path, func(dir string, _ os.FileInfo) error {
+	err := common.IterateSubfolders(path, func(dir string, _ os.FileInfo) error {
 		cred := &CredentialType{}
 		exists, err := conf.pathToDescription(manager, dir+"/description.xml", cred)
 		if err != nil {
@@ -718,7 +718,7 @@ func (conf *Configuration) CopyManagerFromAssets(scheme SchemeManagerIdentifier)
 	if err := os.RemoveAll(filepath.Join(conf.Path, name)); err != nil {
 		return false, err
 	}
-	return true, fs.CopyDirectory(
+	return true, common.CopyDirectory(
 		filepath.Join(conf.assets, name),
 		filepath.Join(conf.Path, name),
 	)
@@ -802,7 +802,7 @@ func (conf *Configuration) InstallSchemeManager(manager *SchemeManager, publicke
 	}
 
 	name := manager.ID
-	if err := fs.EnsureDirectoryExists(filepath.Join(conf.Path, name)); err != nil {
+	if err := common.EnsureDirectoryExists(filepath.Join(conf.Path, name)); err != nil {
 		return err
 	}
 
@@ -812,7 +812,7 @@ func (conf *Configuration) InstallSchemeManager(manager *SchemeManager, publicke
 		return err
 	}
 	if publickey != nil {
-		if err := fs.SaveFile(path+"/pk.pem", publickey); err != nil {
+		if err := common.SaveFile(path+"/pk.pem", publickey); err != nil {
 			return err
 		}
 	} else {
@@ -1057,7 +1057,7 @@ func (i SchemeManagerIndex) Scheme() SchemeManagerIdentifier {
 // parseIndex parses the index file of the specified manager.
 func (conf *Configuration) parseIndex(name string, manager *SchemeManager) (SchemeManagerIndex, error) {
 	path := filepath.Join(conf.Path, name, "index")
-	if err := fs.AssertPathExists(path); err != nil {
+	if err := common.AssertPathExists(path); err != nil {
 		return nil, fmt.Errorf("Missing scheme manager index file; tried %s", path)
 	}
 	indexbts, err := ioutil.ReadFile(path)
@@ -1073,7 +1073,7 @@ func (conf *Configuration) parseIndex(name string, manager *SchemeManager) (Sche
 }
 
 func (conf *Configuration) checkUnsignedFiles(name string, index SchemeManagerIndex) error {
-	return fs.WalkDir(filepath.Join(conf.Path, name), func(path string, info os.FileInfo) error {
+	return common.WalkDir(filepath.Join(conf.Path, name), func(path string, info os.FileInfo) error {
 		relpath, err := filepath.Rel(conf.Path, path)
 		if err != nil {
 			return err
@@ -1130,7 +1130,7 @@ func (conf *Configuration) VerifySchemeManager(manager *SchemeManager) error {
 
 	var exists bool
 	for file := range manager.index {
-		exists, err = fs.PathExists(filepath.Join(conf.Path, file))
+		exists, err = common.PathExists(filepath.Join(conf.Path, file))
 		if err != nil {
 			return err
 		}
@@ -1182,7 +1182,7 @@ func (conf *Configuration) VerifySignature(id SchemeManagerIdentifier) (err erro
 	}()
 
 	dir := filepath.Join(conf.Path, id.String())
-	if err := fs.AssertPathExists(filepath.Join(dir, "index"), filepath.Join(dir, "index.sig"), filepath.Join(dir, "pk.pem")); err != nil {
+	if err := common.AssertPathExists(filepath.Join(dir, "index"), filepath.Join(dir, "index.sig"), filepath.Join(dir, "pk.pem")); err != nil {
 		return errors.New("Missing scheme manager index file, signature, or public key")
 	}
 
@@ -1268,7 +1268,7 @@ func (conf *Configuration) UpdateSchemeManager(id SchemeManagerIdentifier, downl
 		path := filepath.Join(conf.Path, filename)
 		oldHash, known := manager.index[filename]
 		var have bool
-		have, err = fs.PathExists(path)
+		have, err = common.PathExists(path)
 		if err != nil {
 			return err
 		}
@@ -1380,7 +1380,7 @@ func (conf *Configuration) validateIssuer(manager *SchemeManager, issuer *Issuer
 	if err = validateDemoPrefix(issuer.Name); manager.Demo && err != nil {
 		return errors.Errorf("Name of demo issuer %s invalid: %s", issuer.ID, err.Error())
 	}
-	if err = fs.AssertPathExists(filepath.Join(dir, "logo.png")); err != nil {
+	if err = common.AssertPathExists(filepath.Join(dir, "logo.png")); err != nil {
 		conf.Warnings = append(conf.Warnings, fmt.Sprintf("Issuer %s has no logo.png", issuerid.String()))
 	}
 	return nil
@@ -1404,7 +1404,7 @@ func (conf *Configuration) validateCredentialType(manager *SchemeManager, issuer
 	if err := validateDemoPrefix(cred.Name); manager.Demo && err != nil {
 		return errors.Errorf("Name of demo credential %s invalid: %s", cred.ID, err.Error())
 	}
-	if err := fs.AssertPathExists(filepath.Join(dir, "logo.png")); err != nil {
+	if err := common.AssertPathExists(filepath.Join(dir, "logo.png")); err != nil {
 		conf.Warnings = append(conf.Warnings, fmt.Sprintf("Credential type %s has no logo.png", credid.String()))
 	}
 	return conf.validateAttributes(cred)
@@ -1457,7 +1457,7 @@ func (conf *Configuration) validateScheme(scheme *SchemeManager, dir string) err
 		return errors.Errorf("Scheme %s has wrong directory name %s", scheme.ID, filepath.Base(dir))
 	}
 	if scheme.KeyshareServer != "" {
-		if err := fs.AssertPathExists(filepath.Join(dir, "kss-0.pem")); err != nil {
+		if err := common.AssertPathExists(filepath.Join(dir, "kss-0.pem")); err != nil {
 			scheme.Status = SchemeManagerStatusParsingError
 			return errors.Errorf("Scheme %s has keyshare URL but no keyshare public key kss-0.pem", scheme.ID)
 		}
@@ -1620,7 +1620,7 @@ func DefaultSchemesPath() string {
 		return p
 	}
 	p = filepath.Join(p, "irma_configuration")
-	if err := fs.EnsureDirectoryExists(p); err != nil {
+	if err := common.EnsureDirectoryExists(p); err != nil {
 		return ""
 	}
 	return p
@@ -1628,7 +1628,7 @@ func DefaultSchemesPath() string {
 
 func firstExistingPath(paths []string) string {
 	for _, path := range paths {
-		if err := fs.EnsureDirectoryExists(path); err == nil {
+		if err := common.EnsureDirectoryExists(path); err == nil {
 			return path
 		}
 	}

irmago_test.go

@@ -11,7 +11,7 @@ import (
 	"github.com/privacybydesign/gabi"
 	"github.com/privacybydesign/gabi/big"
 	"github.com/privacybydesign/gabi/revocation"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 	"github.com/privacybydesign/irmago/internal/test"
 	"github.com/stretchr/testify/require"
 )
@@ -35,7 +35,7 @@ func TestConfigurationAutocopy(t *testing.T) {
 	defer test.ClearTestStorage(t, storage)
 
 	path := filepath.Join("testdata", "tmp", "client", "irma_configuration")
-	require.NoError(t, fs.CopyDirectory(filepath.Join("testdata", "irma_configuration"), path))
+	require.NoError(t, common.CopyDirectory(filepath.Join("testdata", "irma_configuration"), path))
 	conf, err := NewConfiguration(path, ConfigurationOptions{Assets: filepath.Join("testdata", "irma_configuration_updated")})
 	require.NoError(t, err)
 	require.NoError(t, conf.ParseFolder())

requests.go

@@ -14,7 +14,7 @@ import (
 	"github.com/privacybydesign/gabi"
 	"github.com/privacybydesign/gabi/big"
 	"github.com/privacybydesign/gabi/revocation"
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 )
 
 const (
@@ -800,7 +800,7 @@ func (t *Timestamp) Floor() Timestamp {
 }
 
 func readTimestamp(path string) (*Timestamp, bool, error) {
-	exists, err := fs.PathExists(path)
+	exists, err := common.PathExists(path)
 	if err != nil {
 		return nil, false, err
 	}

schemes.go

@@ -5,7 +5,7 @@ import (
 	"path/filepath"
 	"strings"
 
-	"github.com/privacybydesign/irmago/internal/fs"
+	"github.com/privacybydesign/irmago/internal/common"
 )
 
 // SchemeManagerPointer points to a remote IRMA scheme, containing information to download the scheme,
@@ -76,7 +76,7 @@ func (conf *Configuration) downloadDemoPrivateKeys(scheme *SchemeManager) error
 		skpath := file[:i] + strings.Replace(file[i:],