You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
72 lines
3.0 KiB
72 lines
3.0 KiB
3 years ago
|
// Copyright 2018 by David A. Golden. All rights reserved.
|
||
|
|
//
|
||
|
|
// 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
|
||
|
|
|
||
|
|
package scram
|
||
|
|
|
||
|
|
import (
|
||
|
|
"crypto/sha1"
|
||
|
|
"crypto/sha256"
|
||
|
|
"crypto/sha512"
|
||
|
|
"fmt"
|
||
|
|
"hash"
|
||
|
|
|
||
|
|
"github.com/xdg-go/stringprep"
|
||
|
|
)
|
||
|
|
|
||
|
|
// HashGeneratorFcn abstracts a factory function that returns a hash.Hash
|
||
|
|
// value to be used for SCRAM operations. Generally, one would use the
|
||
|
|
// provided package variables, `scram.SHA1` and `scram.SHA256`, for the most
|
||
|
|
// common forms of SCRAM.
|
||
|
|
type HashGeneratorFcn func() hash.Hash
|
||
|
|
|
||
|
|
// SHA1 is a function that returns a crypto/sha1 hasher and should be used to
|
||
|
|
// create Client objects configured for SHA-1 hashing.
|
||
|
|
var SHA1 HashGeneratorFcn = func() hash.Hash { return sha1.New() }
|
||
|
|
|
||
|
|
// SHA256 is a function that returns a crypto/sha256 hasher and should be used
|
||
|
|
// to create Client objects configured for SHA-256 hashing.
|
||
|
|
var SHA256 HashGeneratorFcn = func() hash.Hash { return sha256.New() }
|
||
|
|
|
||
|
|
// SHA512 is a function that returns a crypto/sha512 hasher and should be used
|
||
|
|
// to create Client objects configured for SHA-512 hashing.
|
||
|
|
var SHA512 HashGeneratorFcn = func() hash.Hash { return sha512.New() }
|
||
|
|
|
||
|
|
// NewClient constructs a SCRAM client component based on a given hash.Hash
|
||
|
|
// factory receiver. This constructor will normalize the username, password
|
||
|
|
// and authzID via the SASLprep algorithm, as recommended by RFC-5802. If
|
||
|
|
// SASLprep fails, the method returns an error.
|
||
|
|
func (f HashGeneratorFcn) NewClient(username, password, authzID string) (*Client, error) {
|
||
|
|
var userprep, passprep, authprep string
|
||
|
|
var err error
|
||
|
|
|
||
|
|
if userprep, err = stringprep.SASLprep.Prepare(username); err != nil {
|
||
|
|
return nil, fmt.Errorf("Error SASLprepping username '%s': %v", username, err)
|
||
|
|
}
|
||
|
|
if passprep, err = stringprep.SASLprep.Prepare(password); err != nil {
|
||
|
|
return nil, fmt.Errorf("Error SASLprepping password '%s': %v", password, err)
|
||
|
|
}
|
||
|
|
if authprep, err = stringprep.SASLprep.Prepare(authzID); err != nil {
|
||
|
|
return nil, fmt.Errorf("Error SASLprepping authzID '%s': %v", authzID, err)
|
||
|
|
}
|
||
|
|
|
||
|
|
return newClient(userprep, passprep, authprep, f), nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// NewClientUnprepped acts like NewClient, except none of the arguments will
|
||
|
|
// be normalized via SASLprep. This is not generally recommended, but is
|
||
|
|
// provided for users that may have custom normalization needs.
|
||
|
|
func (f HashGeneratorFcn) NewClientUnprepped(username, password, authzID string) (*Client, error) {
|
||
|
|
return newClient(username, password, authzID, f), nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// NewServer constructs a SCRAM server component based on a given hash.Hash
|
||
|
|
// factory receiver. To be maximally generic, it uses dependency injection to
|
||
|
|
// handle credential lookup, which is the process of turning a username string
|
||
|
|
// into a struct with stored credentials for authentication.
|
||
|
|
func (f HashGeneratorFcn) NewServer(cl CredentialLookup) (*Server, error) {
|
||
|
|
return newServer(cl, f)
|
||
|
|
}
|