package precis

import "golang.org/x/text/secure/precis"

Package precis contains types and functions for the preparation, enforcement, and comparison of internationalized strings ("PRECIS") as defined in RFC 7564. It also contains several pre-defined profiles for passwords, nicknames, and usernames as defined in RFC 7613 and RFC 7700.

BE ADVISED: This package is under construction and the API may change in backwards incompatible ways and without notice.

Index ¶

Package Files ¶

class.go doc.go nickname.go options.go profile.go profiles.go tables.go transformer.go trieval.go

Constants ¶

const UnicodeVersion = "8.0.0"

UnicodeVersion is the Unicode version from which the tables in this package are derived.

type Option ¶

type Option func(*options)

An Option is used to define the behavior and rules of a Profile.

var (
    // The IgnoreCase option causes the profile to perform a case insensitive
    // comparison during the PRECIS comparison step.
    IgnoreCase Option = ignoreCase

    // The AllowWide option causes the profile to allow full-width and half-width
    // characters by mapping them to their decomposition mappings. This is useful
    // for profiles that are based on the identifier class which would otherwise
    // disallow wide characters.
    AllowWide Option = allowWide

    // The DisallowEmpty option causes the enforcement step to return an error if
    // the resulting string would be empty.
    DisallowEmpty Option = disallowEmpty
)

func AdditionalMapping ¶

func AdditionalMapping(t ...func() transform.Transformer) Option

The AdditionalMapping option defines the additional mapping rule for the Profile by applying Transformer's in sequence.

func Disallow ¶

func Disallow(set runes.Set) Option

The Disallow option further restricts a Profile's allowed characters beyond what is disallowed by the underlying string class.

func FoldCase ¶

func FoldCase(opts ...cases.Option) Option

The FoldCase option defines a Profile's case mapping rule. Options can be provided to determine the type of case folding used.

func Norm ¶

func Norm(f norm.Form) Option

The Norm option defines a Profile's normalization rule. Defaults to NFC.

func Width ¶

func Width(w width.Transformer) Option

The Width option defines a Profile's width mapping rule.

type Profile ¶

type Profile struct {
    transform.NopResetter
    // contains filtered or unexported fields
}

A Profile represents a set of rules for normalizing and validating strings in the PRECIS framework.

var (
    Nickname              Profile = nickname          // Implements the Nickname profile specified in RFC 7700.
    UsernameCaseMapped    Profile = usernamecasemap   // Implements the UsernameCaseMapped profile specified in RFC 7613.
    UsernameCasePreserved Profile = usernamenocasemap // Implements the UsernameCasePreserved profile specified in RFC 7613.
    OpaqueString          Profile = opaquestring      // Implements the OpaqueString profile defined in RFC 7613 for passwords and other secure labels.
)

func NewFreeform ¶

func NewFreeform(opts ...Option) Profile

NewFreeform creates a new PRECIS profile based on the Freeform string class. Profiles created from this class are suitable for use where expressiveness is prioritized over safety like passwords, and display-elements such as nicknames in a chat room.

func NewIdentifier ¶

func NewIdentifier(opts ...Option) Profile

NewIdentifier creates a new PRECIS profile based on the Identifier string class. Profiles created from this class are suitable for use where safety is prioritized over expressiveness like network identifiers, user accounts, chat rooms, and file names.

func (Profile) Allowed ¶

func (p Profile) Allowed() runes.Set

Allowed returns a runes.Set containing every rune that is a member of the underlying profile's string class and not disallowed by any profile specific rules.

func (Profile) Bytes ¶

func (p Profile) Bytes(b []byte) ([]byte, error)

Bytes returns a new byte slice with the result of applying the profile to b.

func (Profile) Compare ¶

func (p Profile) Compare(a, b string) bool

Compare enforces both strings, and then compares them for bit-string identity (byte-for-byte equality). If either string cannot be enforced, the comparison is false.

func (Profile) NewTransformer ¶

func (p Profile) NewTransformer() *Transformer

NewTransformer creates a new transform.Transformer that performs the PRECIS preparation and enforcement steps on the given UTF-8 encoded bytes.

func (Profile) String ¶

func (p Profile) String(s string) (string, error)

String returns a string with the result of applying the profile to s.

type Transformer ¶

type Transformer struct {
    // contains filtered or unexported fields
}

Transformer implements the transform.Transformer interface.

func (Transformer) Bytes ¶

func (t Transformer) Bytes(b []byte) []byte

Bytes returns a new byte slice with the result of applying t to b.

func (Transformer) Reset ¶

func (t Transformer) Reset()

Reset implements the transform.Transformer interface.

func (Transformer) String ¶

func (t Transformer) String(s string) string

String returns a string with the result of applying t to s.

func (Transformer) Transform ¶

func (t Transformer) Transform(dst, src []byte, atEOF bool) (nDst, nSrc int, err error)

Transform implements the transform.Transformer interface.