Rename randutil methods.

command/crypto/jwk/create.go

@@ -562,7 +562,7 @@ func createAction(ctx *cli.Context) error {
 				return errors.Wrap(err, "error reading password")
 			}
 
-			salt, err := randutil.GetRandomSalt(pbkdf2SaltSize)
+			salt, err := randutil.Salt(pbkdf2SaltSize)
 			if err != nil {
 				return err
 			}
@@ -574,7 +574,7 @@ func createAction(ctx *cli.Context) error {
 				P2S:       salt,
 			}
 		} else {
-			key, err := randutil.RandAlphanumeric(32)
+			key, err := randutil.Alphanumeric(32)
 			if err != nil {
 				return errors.Wrap(err, "error generating password")
 			}

command/crypto/jwt/sign.go

@@ -283,7 +283,7 @@ func signAction(ctx *cli.Context) error {
 		c.IssuedAt = jose.NewNumericDate(now)
 	}
 	if c.ID == "" && ctx.IsSet("jti") {
-		if c.ID, err = randutil.RandHex(40); err != nil {
+		if c.ID, err = randutil.Hex(40); err != nil {
 			return errors.Wrap(err, "error creating random jti")
 		}
 	}

command/oauth/cmd.go

@@ -282,12 +282,12 @@ type oauth struct {
 }
 
 func newOauth(provider, clientID, clientSecret, authzEp, tokenEp, scope, loginHint string) (*oauth, error) {
-	state, err := randutil.GenerateRandomRestrictedString(32)
+	state, err := randutil.Alphanumeric(32)
 	if err != nil {
 		return nil, err
 	}
 
-	challenge, err := randutil.GenerateRandomRestrictedString(64)
+	challenge, err := randutil.Alphanumeric(64)
 	if err != nil {
 		return nil, err
 	}

crypto/randutil/random.go

@@ -8,8 +8,19 @@ import (
 	"github.com/pkg/errors"
 )
 
-// GetRandomSalt generates a new salt of the given size.
-func GetRandomSalt(size int) ([]byte, error) {
+var ascii string
+
+func init() {
+	// initialize the charcters in ascii
+	aciiBytes := make([]byte, 94)
+	for i := range aciiBytes {
+		aciiBytes[i] = byte(i + 33)
+	}
+	ascii = string(aciiBytes)
+}
+
+// Salt generates a new random salt of the given size.
+func Salt(size int) ([]byte, error) {
 	salt := make([]byte, size)
 	_, err := io.ReadFull(rand.Reader, salt)
 	if err != nil {
@@ -18,10 +29,10 @@ func GetRandomSalt(size int) ([]byte, error) {
 	return salt, nil
 }
 
-// RandString returns a random string of a given length using the characters
-// in the given string. It splits the string on runes to support UTF-8
+// String returns a random string of a given length using the characters in
+// the given string. It splits the string on runes to support UTF-8
 // characters.
-func RandString(length int, chars string) (string, error) {
+func String(length int, chars string) (string, error) {
 	result := make([]rune, length)
 	runes := []rune(chars)
 	for i := range result {
@@ -34,54 +45,22 @@ func RandString(length int, chars string) (string, error) {
 	return string(result), nil
 }
 
-// RandHex returns a random string of the given length using the hexadecimal
+// Hex returns a random string of the given length using the hexadecimal
 // characters in lower case (0-9+a-f).
-func RandHex(length int) (string, error) {
-	return RandString(length, "0123456789abcdef")
+func Hex(length int) (string, error) {
+	return String(length, "0123456789abcdef")
 }
 
-// RandAlphanumeric returns a random string of the given length using the 62
+// Alphanumeric returns a random string of the given length using the 62
 // alphanumeric characters in the POSIX/C locale (a-z+A-Z+0-9).
-func RandAlphanumeric(length int) (string, error) {
-	return RandString(length, "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ")
+func Alphanumeric(length int) (string, error) {
+	return String(length, "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ")
 }
 
-// GenerateRandomASCIIString returns a securely generated random ASCII string.
-// It reads random numbers from crypto/rand and searches for printable characters.
-// It will return an error if the system's secure random number generator fails to
+// Ascii returns a securely generated random ASCII string. It reads random
+// numbers from crypto/rand and searches for printable characters. It will
+// return an error if the system's secure random number generator fails to
 // function correctly, in which case the caller must not continue.
-func GenerateRandomASCIIString(length int) (string, error) {
-	result := ""
-	for {
-		if len(result) >= length {
-			return result, nil
-		}
-		num, err := rand.Int(rand.Reader, big.NewInt(int64(127)))
-		if err != nil {
-			return "", err
-		}
-		n := num.Int64()
-		// Make sure that the number/byte/letter is inside
-		// the range of printable ASCII characters (excluding space and DEL)
-		if n > 32 && n < 127 {
-			result += string(n)
-		}
-	}
-}
-
-// GenerateRandomRestrictedString returns a securely generated random ASCII string.
-// It reads random numbers from crypto/rand and searches for printable characters.
-// It will return an error if the system's secure random number generator fails to
-// function correctly, in which case the caller must not continue.
-func GenerateRandomRestrictedString(length int) (string, error) {
-	const chars = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-	result := make([]byte, length)
-	for i := range result {
-		num, err := rand.Int(rand.Reader, big.NewInt(int64(len(chars))))
-		if err != nil {
-			return "", err
-		}
-		result[i] = chars[num.Int64()]
-	}
-	return string(result), nil
+func Ascii(length int) (string, error) {
+	return String(length, ascii)
 }

jose/generate.go

@@ -160,7 +160,7 @@ func generateOctKey(size int, alg, use, kid string) (*JSONWebKey, error) {
 		size = DefaultOctSize
 	}
 
-	key, err := randutil.RandAlphanumeric(size)
+	key, err := randutil.Alphanumeric(size)
 	if err != nil {
 		return nil, err
 	}

utils/reader/read.go

@@ -68,7 +68,7 @@ func GeneratePasswordOnEmpty(ptr *string, key string) error {
 
 	if len(*ptr) == 0 {
 		var err error
-		if *ptr, err = randutil.GenerateRandomRestrictedString(passwordLength); err != nil {
+		if *ptr, err = randutil.Alphanumeric(passwordLength); err != nil {
 			return errors.Wrapf(err, "Failed to generate %s", key)
 		}
 		fmt.Printf("\n\n%s: %s\n\n", key, *ptr)