74 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			74 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| /*
 | |
|    Copyright The containerd 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 identifiers provides common validation for identifiers and keys
 | |
| // across containerd.
 | |
| //
 | |
| // Identifiers in containerd must be a alphanumeric, allowing limited
 | |
| // underscores, dashes and dots.
 | |
| //
 | |
| // While the character set may be expanded in the future, identifiers
 | |
| // are guaranteed to be safely used as filesystem path components.
 | |
| package identifiers
 | |
| 
 | |
| import (
 | |
| 	"regexp"
 | |
| 
 | |
| 	"github.com/containerd/containerd/errdefs"
 | |
| 	"github.com/pkg/errors"
 | |
| )
 | |
| 
 | |
| const (
 | |
| 	maxLength  = 76
 | |
| 	alphanum   = `[A-Za-z0-9]+`
 | |
| 	separators = `[._-]`
 | |
| )
 | |
| 
 | |
| var (
 | |
| 	// identifierRe defines the pattern for valid identifiers.
 | |
| 	identifierRe = regexp.MustCompile(reAnchor(alphanum + reGroup(separators+reGroup(alphanum)) + "*"))
 | |
| )
 | |
| 
 | |
| // Validate return nil if the string s is a valid identifier.
 | |
| //
 | |
| // identifiers must be valid domain names according to RFC 1035, section 2.3.1.  To
 | |
| // enforce case insensitvity, all characters must be lower case.
 | |
| //
 | |
| // In general, identifiers that pass this validation, should be safe for use as
 | |
| // a domain names or filesystem path component.
 | |
| func Validate(s string) error {
 | |
| 	if len(s) == 0 {
 | |
| 		return errors.Wrapf(errdefs.ErrInvalidArgument, "identifier must not be empty")
 | |
| 	}
 | |
| 
 | |
| 	if len(s) > maxLength {
 | |
| 		return errors.Wrapf(errdefs.ErrInvalidArgument, "identifier %q greater than maximum length (%d characters)", s, maxLength)
 | |
| 	}
 | |
| 
 | |
| 	if !identifierRe.MatchString(s) {
 | |
| 		return errors.Wrapf(errdefs.ErrInvalidArgument, "identifier %q must match %v", s, identifierRe)
 | |
| 	}
 | |
| 	return nil
 | |
| }
 | |
| 
 | |
| func reGroup(s string) string {
 | |
| 	return `(?:` + s + `)`
 | |
| }
 | |
| 
 | |
| func reAnchor(s string) string {
 | |
| 	return `^` + s + `$`
 | |
| }
 | 
