vendor update for E2E framework

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

vendor/k8s.io/cluster-bootstrap/token/util/helpers.go

@@ -0,0 +1,133 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"bufio"
+	"crypto/rand"
+	"fmt"
+	"regexp"
+	"strings"
+
+	"k8s.io/apimachinery/pkg/util/sets"
+	"k8s.io/cluster-bootstrap/token/api"
+)
+
+// validBootstrapTokenChars defines the characters a bootstrap token can consist of
+const validBootstrapTokenChars = "0123456789abcdefghijklmnopqrstuvwxyz"
+
+var (
+	// BootstrapTokenRegexp is a compiled regular expression of TokenRegexpString
+	BootstrapTokenRegexp = regexp.MustCompile(api.BootstrapTokenPattern)
+	// BootstrapTokenIDRegexp is a compiled regular expression of TokenIDRegexpString
+	BootstrapTokenIDRegexp = regexp.MustCompile(api.BootstrapTokenIDPattern)
+	// BootstrapGroupRegexp is a compiled regular expression of BootstrapGroupPattern
+	BootstrapGroupRegexp = regexp.MustCompile(api.BootstrapGroupPattern)
+)
+
+// GenerateBootstrapToken generates a new, random Bootstrap Token.
+func GenerateBootstrapToken() (string, error) {
+	tokenID, err := randBytes(api.BootstrapTokenIDBytes)
+	if err != nil {
+		return "", err
+	}
+
+	tokenSecret, err := randBytes(api.BootstrapTokenSecretBytes)
+	if err != nil {
+		return "", err
+	}
+
+	return TokenFromIDAndSecret(tokenID, tokenSecret), nil
+}
+
+// randBytes returns a random string consisting of the characters in
+// validBootstrapTokenChars, with the length customized by the parameter
+func randBytes(length int) (string, error) {
+	// len("0123456789abcdefghijklmnopqrstuvwxyz") = 36 which doesn't evenly divide
+	// the possible values of a byte: 256 mod 36 = 4. Discard any random bytes we
+	// read that are >= 252 so the bytes we evenly divide the character set.
+	const maxByteValue = 252
+
+	var (
+		b     byte
+		err   error
+		token = make([]byte, length)
+	)
+
+	reader := bufio.NewReaderSize(rand.Reader, length*2)
+	for i := range token {
+		for {
+			if b, err = reader.ReadByte(); err != nil {
+				return "", err
+			}
+			if b < maxByteValue {
+				break
+			}
+		}
+
+		token[i] = validBootstrapTokenChars[int(b)%len(validBootstrapTokenChars)]
+	}
+
+	return string(token), nil
+}
+
+// TokenFromIDAndSecret returns the full token which is of the form "{id}.{secret}"
+func TokenFromIDAndSecret(id, secret string) string {
+	return fmt.Sprintf("%s.%s", id, secret)
+}
+
+// IsValidBootstrapToken returns whether the given string is valid as a Bootstrap Token and
+// in other words satisfies the BootstrapTokenRegexp
+func IsValidBootstrapToken(token string) bool {
+	return BootstrapTokenRegexp.MatchString(token)
+}
+
+// IsValidBootstrapTokenID returns whether the given string is valid as a Bootstrap Token ID and
+// in other words satisfies the BootstrapTokenIDRegexp
+func IsValidBootstrapTokenID(tokenID string) bool {
+	return BootstrapTokenIDRegexp.MatchString(tokenID)
+}
+
+// BootstrapTokenSecretName returns the expected name for the Secret storing the
+// Bootstrap Token in the Kubernetes API.
+func BootstrapTokenSecretName(tokenID string) string {
+	return fmt.Sprintf("%s%s", api.BootstrapTokenSecretPrefix, tokenID)
+}
+
+// ValidateBootstrapGroupName checks if the provided group name is a valid
+// bootstrap group name. Returns nil if valid or a validation error if invalid.
+func ValidateBootstrapGroupName(name string) error {
+	if BootstrapGroupRegexp.Match([]byte(name)) {
+		return nil
+	}
+	return fmt.Errorf("bootstrap group %q is invalid (must match %s)", name, api.BootstrapGroupPattern)
+}
+
+// ValidateUsages validates that the passed in string are valid usage strings for bootstrap tokens.
+func ValidateUsages(usages []string) error {
+	validUsages := sets.NewString(api.KnownTokenUsages...)
+	invalidUsages := sets.NewString()
+	for _, usage := range usages {
+		if !validUsages.Has(usage) {
+			invalidUsages.Insert(usage)
+		}
+	}
+	if len(invalidUsages) > 0 {
+		return fmt.Errorf("invalid bootstrap token usage string: %s, valid usage options: %s", strings.Join(invalidUsages.List(), ","), strings.Join(api.KnownTokenUsages, ","))
+	}
+	return nil
+}