More documentation, and alias function for loading a KeyStore from a filepath path

README.md

@@ -1,3 +1,3 @@
 # MJWT
 
-A simple wrapper for JWT. Contains an AccessToken and RefreshToken model.
+A simple wrapper for JWT. Contains an AccessToken and RefreshToken model.

issuer.go

@@ -7,6 +7,8 @@ import (
 	"time"
 )
 
+// Issuer provides the signing for a PrivateKey identified by the KID in the
+// provided KeyStore
 type Issuer struct {
 	issuer   string
 	kid      string
@@ -14,10 +16,12 @@ type Issuer struct {
 	keystore *KeyStore
 }
 
+// NewIssuer creates an Issuer with an empty KeyStore
 func NewIssuer(name, kid string, signing jwt.SigningMethod) (*Issuer, error) {
 	return NewIssuerWithKeyStore(name, kid, signing, NewKeyStore())
 }
 
+// NewIssuerWithKeyStore creates an Issuer with a provided KeyStore
 func NewIssuerWithKeyStore(name, kid string, signing jwt.SigningMethod, keystore *KeyStore) (*Issuer, error) {
 	i := &Issuer{name, kid, signing, keystore}
 	if i.keystore.HasPrivateKey(kid) {
@@ -31,10 +35,12 @@ func NewIssuerWithKeyStore(name, kid string, signing jwt.SigningMethod, keystore
 	return i, i.keystore.SaveSingleKey(kid)
 }
 
+// GenerateJwt produces a signed JWT in string form
 func (i *Issuer) GenerateJwt(sub, id string, aud jwt.ClaimStrings, dur time.Duration, claims Claims) (string, error) {
 	return i.SignJwt(wrapClaims[Claims](sub, id, i.issuer, aud, dur, claims))
 }
 
+// SignJwt produces a signed JWT in string form from a raw jwt.Claims structure
 func (i *Issuer) SignJwt(wrapped jwt.Claims) (string, error) {
 	key, err := i.PrivateKey()
 	if err != nil {
@@ -45,10 +51,12 @@ func (i *Issuer) SignJwt(wrapped jwt.Claims) (string, error) {
 	return token.SignedString(key)
 }
 
+// PrivateKey outputs the rsa.PrivateKey from the KID of the Issuer
 func (i *Issuer) PrivateKey() (*rsa.PrivateKey, error) {
 	return i.keystore.GetPrivateKey(i.kid)
 }
 
+// KeyStore outputs the underlying KeyStore used by the Issuer
 func (i *Issuer) KeyStore() *KeyStore {
 	return i.keystore
 }

jwks.go

@@ -6,6 +6,7 @@ import (
 	"io"
 )
 
+// WriteJwkSetJson outputs the public keys used by the Issuers
 func WriteJwkSetJson(w io.Writer, issuers []*Issuer) error {
 	enc := json.NewEncoder(w)
 	enc.SetIndent("", "  ")

keystore.go

@@ -26,12 +26,14 @@ const PemExt = ".pem"
 const PrivatePemExt = PrivateStr + PemExt
 const PublicPemExt = PublicStr + PemExt
 
+// KeyStore provides a store for a collection of private/public keypair structs
 type KeyStore struct {
 	mu    *sync.RWMutex
 	store map[string]*keyPair
 	dir   afero.Fs
 }
 
+// NewKeyStore creates an empty KeyStore
 func NewKeyStore() *KeyStore {
 	return &KeyStore{
 		mu:    new(sync.RWMutex),
@@ -39,12 +41,28 @@ func NewKeyStore() *KeyStore {
 	}
 }
 
+// NewKeyStoreWithDir creates an empty KeyStore with an underlying afero.Fs
+// filesystem for saving the internal store data
 func NewKeyStoreWithDir(dir afero.Fs) *KeyStore {
 	keyStore := NewKeyStore()
 	keyStore.dir = dir
 	return keyStore
 }
 
+// NewKeyStoreFromPath creates an empty KeyStore. The provided path is walked to
+// load the private/public keys. See implementation in NewKeyStoreFromDir.
+func NewKeyStoreFromPath(dir string) (*KeyStore, error) {
+	abs, err := filepath.Abs(dir)
+	if err != nil {
+		return nil, err
+	}
+	return NewKeyStoreFromDir(afero.NewBasePathFs(afero.NewOsFs(), abs))
+}
+
+// NewKeyStoreFromDir creates an empty KeyStore. The provided afero.Fs is walked
+// to find all private/public keys in files named `.private.pem` and
+// `.public.pem` respectively. The keys are loaded into the KeyStore and any
+// errors are returned immediately.
 func NewKeyStoreFromDir(dir afero.Fs) (*KeyStore, error) {
 	keyStore := NewKeyStoreWithDir(dir)
 	err := afero.Walk(dir, ".", func(path string, d fs.FileInfo, err error) error {
@@ -94,6 +112,7 @@ type keyPair struct {
 	public  *rsa.PublicKey
 }
 
+// LoadPrivateKey sets the rsa.PrivateKey/rsa.PublicKey for the KID
 func (k *KeyStore) LoadPrivateKey(kid string, key *rsa.PrivateKey) {
 	k.mu.Lock()
 	if k.store[kid] == nil {
@@ -104,6 +123,7 @@ func (k *KeyStore) LoadPrivateKey(kid string, key *rsa.PrivateKey) {
 	k.mu.Unlock()
 }
 
+// LoadPublicKey sets the rsa.PublicKey for the KID
 func (k *KeyStore) LoadPublicKey(kid string, key *rsa.PublicKey) {
 	k.mu.Lock()
 	if k.store[kid] == nil {
@@ -113,12 +133,14 @@ func (k *KeyStore) LoadPublicKey(kid string, key *rsa.PublicKey) {
 	k.mu.Unlock()
 }
 
+// RemoveKey deletes the KID keypair from the KeyStore
 func (k *KeyStore) RemoveKey(kid string) {
 	k.mu.Lock()
 	delete(k.store, kid)
 	k.mu.Unlock()
 }
 
+// ListKeys provides a slice of the KIDs for all keys loaded in the KeyStore
 func (k *KeyStore) ListKeys() []string {
 	k.mu.RLock()
 	defer k.mu.RUnlock()
@@ -129,6 +151,7 @@ func (k *KeyStore) ListKeys() []string {
 	return keys
 }
 
+// GetPrivateKey outputs the rsa.PrivateKey for the KID from the KeyStore
 func (k *KeyStore) GetPrivateKey(kid string) (*rsa.PrivateKey, error) {
 	k.mu.RLock()
 	defer k.mu.RUnlock()
@@ -138,6 +161,7 @@ func (k *KeyStore) GetPrivateKey(kid string) (*rsa.PrivateKey, error) {
 	return k.store[kid].private, nil
 }
 
+// GetPublicKey outputs the rsa.PublicKey for the KID from the KeyStore
 func (k *KeyStore) GetPublicKey(kid string) (*rsa.PublicKey, error) {
 	k.mu.RLock()
 	defer k.mu.RUnlock()
@@ -147,12 +171,15 @@ func (k *KeyStore) GetPublicKey(kid string) (*rsa.PublicKey, error) {
 	return k.store[kid].public, nil
 }
 
+// ClearKeys clears the internal map and makes a new map to release used memory
 func (k *KeyStore) ClearKeys() {
 	k.mu.Lock()
 	clear(k.store)
+	k.store = make(map[string]*keyPair)
 	k.mu.Unlock()
 }
 
+// HasPrivateKey outputs true if the KID is found in the KeyStore
 func (k *KeyStore) HasPrivateKey(kid string) bool {
 	k.mu.RLock()
 	defer k.mu.RUnlock()
@@ -164,6 +191,7 @@ func (k *KeyStore) internalHasPrivateKey(kid string) bool {
 	return v != nil && v.private != nil
 }
 
+// HasPublicKey outputs true if the KID is found in the KeyStore
 func (k *KeyStore) HasPublicKey(kid string) bool {
 	k.mu.RLock()
 	defer k.mu.RUnlock()
@@ -175,6 +203,9 @@ func (k *KeyStore) internalHasPublicKey(kid string) bool {
 	return v != nil && v.public != nil
 }
 
+// VerifyJwt parses the provided token string and validates it against the KID
+// using the KeyStore. An error is returned if the token fails to parse or if
+// there is no matching KID in the KeyStore.
 func (k *KeyStore) VerifyJwt(token string, claims baseTypeClaim) (*jwt.Token, error) {
 	withClaims, err := jwt.ParseWithClaims(token, claims, func(token *jwt.Token) (interface{}, error) {
 		kid, ok := token.Header["kid"].(string)
@@ -189,6 +220,8 @@ func (k *KeyStore) VerifyJwt(token string, claims baseTypeClaim) (*jwt.Token, er
 	return withClaims, claims.Valid()
 }
 
+// SaveSingleKey writes the rsa.PrivateKey/rsa.PublicKey for the requested KID to
+// the underlying afero.Fs.
 func (k *KeyStore) SaveSingleKey(kid string) error {
 	if k.dir == nil {
 		return nil
@@ -201,16 +234,11 @@ func (k *KeyStore) SaveSingleKey(kid string) error {
 		return ErrMissingKeyPair
 	}
 
-	var errs []error
-	if pair.private != nil {
-		errs = append(errs, afero.WriteFile(k.dir, kid+PrivatePemExt, rsaprivate.Encode(pair.private), 0600))
-	}
-	if pair.public != nil {
-		errs = append(errs, afero.WriteFile(k.dir, kid+PublicPemExt, rsapublic.Encode(pair.public), 0600))
-	}
-	return errors.Join(errs...)
+	return writeSingleKey(k.dir, kid, pair)
 }
 
+// SaveKeys writes the rsa.PrivateKey/rsa.PublicKey for the requested KID to the
+// underlying afero.Fs.
 func (k *KeyStore) SaveKeys() error {
 	k.mu.RLock()
 	defer k.mu.RUnlock()
@@ -219,15 +247,19 @@ func (k *KeyStore) SaveKeys() error {
 	workers.SetLimit(runtime.NumCPU())
 	for kid, pair := range k.store {
 		workers.Go(func() error {
-			var errs []error
-			if pair.private != nil {
-				errs = append(errs, afero.WriteFile(k.dir, kid+PrivatePemExt, rsaprivate.Encode(pair.private), 0600))
-			}
-			if pair.public != nil {
-				errs = append(errs, afero.WriteFile(k.dir, kid+PublicPemExt, rsapublic.Encode(pair.public), 0600))
-			}
-			return errors.Join(errs...)
+			return writeSingleKey(k.dir, kid, pair)
 		})
 	}
 	return workers.Wait()
 }
+
+func writeSingleKey(dir afero.Fs, kid string, pair *keyPair) error {
+	var errs []error
+	if pair.private != nil {
+		errs = append(errs, afero.WriteFile(dir, kid+PrivatePemExt, rsaprivate.Encode(pair.private), 0600))
+	}
+	if pair.public != nil {
+		errs = append(errs, afero.WriteFile(dir, kid+PublicPemExt, rsapublic.Encode(pair.public), 0600))
+	}
+	return errors.Join(errs...)
+}