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authorWim <wim@42.be>2019-06-16 23:33:25 +0200
committerGitHub <noreply@github.com>2019-06-16 23:33:25 +0200
commitcb712ff37d3c20a21695e00c52fff213a6fd40b4 (patch)
tree0ba0ee4f55bf6ace2656562465cc82d807e741b9 /vendor/golang.org/x/net/idna/idna10.0.0.go
parentf4ae61044888f591830e6c1be9a2bdb14f88943e (diff)
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Update vendor (#852)
Diffstat (limited to 'vendor/golang.org/x/net/idna/idna10.0.0.go')
-rw-r--r--vendor/golang.org/x/net/idna/idna10.0.0.go734
1 files changed, 734 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/idna/idna10.0.0.go b/vendor/golang.org/x/net/idna/idna10.0.0.go
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index 00000000..a98a31f4
--- /dev/null
+++ b/vendor/golang.org/x/net/idna/idna10.0.0.go
@@ -0,0 +1,734 @@
+// Code generated by running "go generate" in golang.org/x/text. DO NOT EDIT.
+
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.10
+
+// Package idna implements IDNA2008 using the compatibility processing
+// defined by UTS (Unicode Technical Standard) #46, which defines a standard to
+// deal with the transition from IDNA2003.
+//
+// IDNA2008 (Internationalized Domain Names for Applications), is defined in RFC
+// 5890, RFC 5891, RFC 5892, RFC 5893 and RFC 5894.
+// UTS #46 is defined in https://www.unicode.org/reports/tr46.
+// See https://unicode.org/cldr/utility/idna.jsp for a visualization of the
+// differences between these two standards.
+package idna // import "golang.org/x/net/idna"
+
+import (
+ "fmt"
+ "strings"
+ "unicode/utf8"
+
+ "golang.org/x/text/secure/bidirule"
+ "golang.org/x/text/unicode/bidi"
+ "golang.org/x/text/unicode/norm"
+)
+
+// NOTE: Unlike common practice in Go APIs, the functions will return a
+// sanitized domain name in case of errors. Browsers sometimes use a partially
+// evaluated string as lookup.
+// TODO: the current error handling is, in my opinion, the least opinionated.
+// Other strategies are also viable, though:
+// Option 1) Return an empty string in case of error, but allow the user to
+// specify explicitly which errors to ignore.
+// Option 2) Return the partially evaluated string if it is itself a valid
+// string, otherwise return the empty string in case of error.
+// Option 3) Option 1 and 2.
+// Option 4) Always return an empty string for now and implement Option 1 as
+// needed, and document that the return string may not be empty in case of
+// error in the future.
+// I think Option 1 is best, but it is quite opinionated.
+
+// ToASCII is a wrapper for Punycode.ToASCII.
+func ToASCII(s string) (string, error) {
+ return Punycode.process(s, true)
+}
+
+// ToUnicode is a wrapper for Punycode.ToUnicode.
+func ToUnicode(s string) (string, error) {
+ return Punycode.process(s, false)
+}
+
+// An Option configures a Profile at creation time.
+type Option func(*options)
+
+// Transitional sets a Profile to use the Transitional mapping as defined in UTS
+// #46. This will cause, for example, "ß" to be mapped to "ss". Using the
+// transitional mapping provides a compromise between IDNA2003 and IDNA2008
+// compatibility. It is used by most browsers when resolving domain names. This
+// option is only meaningful if combined with MapForLookup.
+func Transitional(transitional bool) Option {
+ return func(o *options) { o.transitional = true }
+}
+
+// VerifyDNSLength sets whether a Profile should fail if any of the IDN parts
+// are longer than allowed by the RFC.
+func VerifyDNSLength(verify bool) Option {
+ return func(o *options) { o.verifyDNSLength = verify }
+}
+
+// RemoveLeadingDots removes leading label separators. Leading runes that map to
+// dots, such as U+3002 IDEOGRAPHIC FULL STOP, are removed as well.
+//
+// This is the behavior suggested by the UTS #46 and is adopted by some
+// browsers.
+func RemoveLeadingDots(remove bool) Option {
+ return func(o *options) { o.removeLeadingDots = remove }
+}
+
+// ValidateLabels sets whether to check the mandatory label validation criteria
+// as defined in Section 5.4 of RFC 5891. This includes testing for correct use
+// of hyphens ('-'), normalization, validity of runes, and the context rules.
+func ValidateLabels(enable bool) Option {
+ return func(o *options) {
+ // Don't override existing mappings, but set one that at least checks
+ // normalization if it is not set.
+ if o.mapping == nil && enable {
+ o.mapping = normalize
+ }
+ o.trie = trie
+ o.validateLabels = enable
+ o.fromPuny = validateFromPunycode
+ }
+}
+
+// StrictDomainName limits the set of permissible ASCII characters to those
+// allowed in domain names as defined in RFC 1034 (A-Z, a-z, 0-9 and the
+// hyphen). This is set by default for MapForLookup and ValidateForRegistration.
+//
+// This option is useful, for instance, for browsers that allow characters
+// outside this range, for example a '_' (U+005F LOW LINE). See
+// http://www.rfc-editor.org/std/std3.txt for more details This option
+// corresponds to the UseSTD3ASCIIRules option in UTS #46.
+func StrictDomainName(use bool) Option {
+ return func(o *options) {
+ o.trie = trie
+ o.useSTD3Rules = use
+ o.fromPuny = validateFromPunycode
+ }
+}
+
+// NOTE: the following options pull in tables. The tables should not be linked
+// in as long as the options are not used.
+
+// BidiRule enables the Bidi rule as defined in RFC 5893. Any application
+// that relies on proper validation of labels should include this rule.
+func BidiRule() Option {
+ return func(o *options) { o.bidirule = bidirule.ValidString }
+}
+
+// ValidateForRegistration sets validation options to verify that a given IDN is
+// properly formatted for registration as defined by Section 4 of RFC 5891.
+func ValidateForRegistration() Option {
+ return func(o *options) {
+ o.mapping = validateRegistration
+ StrictDomainName(true)(o)
+ ValidateLabels(true)(o)
+ VerifyDNSLength(true)(o)
+ BidiRule()(o)
+ }
+}
+
+// MapForLookup sets validation and mapping options such that a given IDN is
+// transformed for domain name lookup according to the requirements set out in
+// Section 5 of RFC 5891. The mappings follow the recommendations of RFC 5894,
+// RFC 5895 and UTS 46. It does not add the Bidi Rule. Use the BidiRule option
+// to add this check.
+//
+// The mappings include normalization and mapping case, width and other
+// compatibility mappings.
+func MapForLookup() Option {
+ return func(o *options) {
+ o.mapping = validateAndMap
+ StrictDomainName(true)(o)
+ ValidateLabels(true)(o)
+ }
+}
+
+type options struct {
+ transitional bool
+ useSTD3Rules bool
+ validateLabels bool
+ verifyDNSLength bool
+ removeLeadingDots bool
+
+ trie *idnaTrie
+
+ // fromPuny calls validation rules when converting A-labels to U-labels.
+ fromPuny func(p *Profile, s string) error
+
+ // mapping implements a validation and mapping step as defined in RFC 5895
+ // or UTS 46, tailored to, for example, domain registration or lookup.
+ mapping func(p *Profile, s string) (mapped string, isBidi bool, err error)
+
+ // bidirule, if specified, checks whether s conforms to the Bidi Rule
+ // defined in RFC 5893.
+ bidirule func(s string) bool
+}
+
+// A Profile defines the configuration of an IDNA mapper.
+type Profile struct {
+ options
+}
+
+func apply(o *options, opts []Option) {
+ for _, f := range opts {
+ f(o)
+ }
+}
+
+// New creates a new Profile.
+//
+// With no options, the returned Profile is the most permissive and equals the
+// Punycode Profile. Options can be passed to further restrict the Profile. The
+// MapForLookup and ValidateForRegistration options set a collection of options,
+// for lookup and registration purposes respectively, which can be tailored by
+// adding more fine-grained options, where later options override earlier
+// options.
+func New(o ...Option) *Profile {
+ p := &Profile{}
+ apply(&p.options, o)
+ return p
+}
+
+// ToASCII converts a domain or domain label to its ASCII form. For example,
+// ToASCII("bücher.example.com") is "xn--bcher-kva.example.com", and
+// ToASCII("golang") is "golang". If an error is encountered it will return
+// an error and a (partially) processed result.
+func (p *Profile) ToASCII(s string) (string, error) {
+ return p.process(s, true)
+}
+
+// ToUnicode converts a domain or domain label to its Unicode form. For example,
+// ToUnicode("xn--bcher-kva.example.com") is "bücher.example.com", and
+// ToUnicode("golang") is "golang". If an error is encountered it will return
+// an error and a (partially) processed result.
+func (p *Profile) ToUnicode(s string) (string, error) {
+ pp := *p
+ pp.transitional = false
+ return pp.process(s, false)
+}
+
+// String reports a string with a description of the profile for debugging
+// purposes. The string format may change with different versions.
+func (p *Profile) String() string {
+ s := ""
+ if p.transitional {
+ s = "Transitional"
+ } else {
+ s = "NonTransitional"
+ }
+ if p.useSTD3Rules {
+ s += ":UseSTD3Rules"
+ }
+ if p.validateLabels {
+ s += ":ValidateLabels"
+ }
+ if p.verifyDNSLength {
+ s += ":VerifyDNSLength"
+ }
+ return s
+}
+
+var (
+ // Punycode is a Profile that does raw punycode processing with a minimum
+ // of validation.
+ Punycode *Profile = punycode
+
+ // Lookup is the recommended profile for looking up domain names, according
+ // to Section 5 of RFC 5891. The exact configuration of this profile may
+ // change over time.
+ Lookup *Profile = lookup
+
+ // Display is the recommended profile for displaying domain names.
+ // The configuration of this profile may change over time.
+ Display *Profile = display
+
+ // Registration is the recommended profile for checking whether a given
+ // IDN is valid for registration, according to Section 4 of RFC 5891.
+ Registration *Profile = registration
+
+ punycode = &Profile{}
+ lookup = &Profile{options{
+ transitional: true,
+ useSTD3Rules: true,
+ validateLabels: true,
+ trie: trie,
+ fromPuny: validateFromPunycode,
+ mapping: validateAndMap,
+ bidirule: bidirule.ValidString,
+ }}
+ display = &Profile{options{
+ useSTD3Rules: true,
+ validateLabels: true,
+ trie: trie,
+ fromPuny: validateFromPunycode,
+ mapping: validateAndMap,
+ bidirule: bidirule.ValidString,
+ }}
+ registration = &Profile{options{
+ useSTD3Rules: true,
+ validateLabels: true,
+ verifyDNSLength: true,
+ trie: trie,
+ fromPuny: validateFromPunycode,
+ mapping: validateRegistration,
+ bidirule: bidirule.ValidString,
+ }}
+
+ // TODO: profiles
+ // Register: recommended for approving domain names: don't do any mappings
+ // but rather reject on invalid input. Bundle or block deviation characters.
+)
+
+type labelError struct{ label, code_ string }
+
+func (e labelError) code() string { return e.code_ }
+func (e labelError) Error() string {
+ return fmt.Sprintf("idna: invalid label %q", e.label)
+}
+
+type runeError rune
+
+func (e runeError) code() string { return "P1" }
+func (e runeError) Error() string {
+ return fmt.Sprintf("idna: disallowed rune %U", e)
+}
+
+// process implements the algorithm described in section 4 of UTS #46,
+// see https://www.unicode.org/reports/tr46.
+func (p *Profile) process(s string, toASCII bool) (string, error) {
+ var err error
+ var isBidi bool
+ if p.mapping != nil {
+ s, isBidi, err = p.mapping(p, s)
+ }
+ // Remove leading empty labels.
+ if p.removeLeadingDots {
+ for ; len(s) > 0 && s[0] == '.'; s = s[1:] {
+ }
+ }
+ // TODO: allow for a quick check of the tables data.
+ // It seems like we should only create this error on ToASCII, but the
+ // UTS 46 conformance tests suggests we should always check this.
+ if err == nil && p.verifyDNSLength && s == "" {
+ err = &labelError{s, "A4"}
+ }
+ labels := labelIter{orig: s}
+ for ; !labels.done(); labels.next() {
+ label := labels.label()
+ if label == "" {
+ // Empty labels are not okay. The label iterator skips the last
+ // label if it is empty.
+ if err == nil && p.verifyDNSLength {
+ err = &labelError{s, "A4"}
+ }
+ continue
+ }
+ if strings.HasPrefix(label, acePrefix) {
+ u, err2 := decode(label[len(acePrefix):])
+ if err2 != nil {
+ if err == nil {
+ err = err2
+ }
+ // Spec says keep the old label.
+ continue
+ }
+ isBidi = isBidi || bidirule.DirectionString(u) != bidi.LeftToRight
+ labels.set(u)
+ if err == nil && p.validateLabels {
+ err = p.fromPuny(p, u)
+ }
+ if err == nil {
+ // This should be called on NonTransitional, according to the
+ // spec, but that currently does not have any effect. Use the
+ // original profile to preserve options.
+ err = p.validateLabel(u)
+ }
+ } else if err == nil {
+ err = p.validateLabel(label)
+ }
+ }
+ if isBidi && p.bidirule != nil && err == nil {
+ for labels.reset(); !labels.done(); labels.next() {
+ if !p.bidirule(labels.label()) {
+ err = &labelError{s, "B"}
+ break
+ }
+ }
+ }
+ if toASCII {
+ for labels.reset(); !labels.done(); labels.next() {
+ label := labels.label()
+ if !ascii(label) {
+ a, err2 := encode(acePrefix, label)
+ if err == nil {
+ err = err2
+ }
+ label = a
+ labels.set(a)
+ }
+ n := len(label)
+ if p.verifyDNSLength && err == nil && (n == 0 || n > 63) {
+ err = &labelError{label, "A4"}
+ }
+ }
+ }
+ s = labels.result()
+ if toASCII && p.verifyDNSLength && err == nil {
+ // Compute the length of the domain name minus the root label and its dot.
+ n := len(s)
+ if n > 0 && s[n-1] == '.' {
+ n--
+ }
+ if len(s) < 1 || n > 253 {
+ err = &labelError{s, "A4"}
+ }
+ }
+ return s, err
+}
+
+func normalize(p *Profile, s string) (mapped string, isBidi bool, err error) {
+ // TODO: consider first doing a quick check to see if any of these checks
+ // need to be done. This will make it slower in the general case, but
+ // faster in the common case.
+ mapped = norm.NFC.String(s)
+ isBidi = bidirule.DirectionString(mapped) == bidi.RightToLeft
+ return mapped, isBidi, nil
+}
+
+func validateRegistration(p *Profile, s string) (idem string, bidi bool, err error) {
+ // TODO: filter need for normalization in loop below.
+ if !norm.NFC.IsNormalString(s) {
+ return s, false, &labelError{s, "V1"}
+ }
+ for i := 0; i < len(s); {
+ v, sz := trie.lookupString(s[i:])
+ if sz == 0 {
+ return s, bidi, runeError(utf8.RuneError)
+ }
+ bidi = bidi || info(v).isBidi(s[i:])
+ // Copy bytes not copied so far.
+ switch p.simplify(info(v).category()) {
+ // TODO: handle the NV8 defined in the Unicode idna data set to allow
+ // for strict conformance to IDNA2008.
+ case valid, deviation:
+ case disallowed, mapped, unknown, ignored:
+ r, _ := utf8.DecodeRuneInString(s[i:])
+ return s, bidi, runeError(r)
+ }
+ i += sz
+ }
+ return s, bidi, nil
+}
+
+func (c info) isBidi(s string) bool {
+ if !c.isMapped() {
+ return c&attributesMask == rtl
+ }
+ // TODO: also store bidi info for mapped data. This is possible, but a bit
+ // cumbersome and not for the common case.
+ p, _ := bidi.LookupString(s)
+ switch p.Class() {
+ case bidi.R, bidi.AL, bidi.AN:
+ return true
+ }
+ return false
+}
+
+func validateAndMap(p *Profile, s string) (vm string, bidi bool, err error) {
+ var (
+ b []byte
+ k int
+ )
+ // combinedInfoBits contains the or-ed bits of all runes. We use this
+ // to derive the mayNeedNorm bit later. This may trigger normalization
+ // overeagerly, but it will not do so in the common case. The end result
+ // is another 10% saving on BenchmarkProfile for the common case.
+ var combinedInfoBits info
+ for i := 0; i < len(s); {
+ v, sz := trie.lookupString(s[i:])
+ if sz == 0 {
+ b = append(b, s[k:i]...)
+ b = append(b, "\ufffd"...)
+ k = len(s)
+ if err == nil {
+ err = runeError(utf8.RuneError)
+ }
+ break
+ }
+ combinedInfoBits |= info(v)
+ bidi = bidi || info(v).isBidi(s[i:])
+ start := i
+ i += sz
+ // Copy bytes not copied so far.
+ switch p.simplify(info(v).category()) {
+ case valid:
+ continue
+ case disallowed:
+ if err == nil {
+ r, _ := utf8.DecodeRuneInString(s[start:])
+ err = runeError(r)
+ }
+ continue
+ case mapped, deviation:
+ b = append(b, s[k:start]...)
+ b = info(v).appendMapping(b, s[start:i])
+ case ignored:
+ b = append(b, s[k:start]...)
+ // drop the rune
+ case unknown:
+ b = append(b, s[k:start]...)
+ b = append(b, "\ufffd"...)
+ }
+ k = i
+ }
+ if k == 0 {
+ // No changes so far.
+ if combinedInfoBits&mayNeedNorm != 0 {
+ s = norm.NFC.String(s)
+ }
+ } else {
+ b = append(b, s[k:]...)
+ if norm.NFC.QuickSpan(b) != len(b) {
+ b = norm.NFC.Bytes(b)
+ }
+ // TODO: the punycode converters require strings as input.
+ s = string(b)
+ }
+ return s, bidi, err
+}
+
+// A labelIter allows iterating over domain name labels.
+type labelIter struct {
+ orig string
+ slice []string
+ curStart int
+ curEnd int
+ i int
+}
+
+func (l *labelIter) reset() {
+ l.curStart = 0
+ l.curEnd = 0
+ l.i = 0
+}
+
+func (l *labelIter) done() bool {
+ return l.curStart >= len(l.orig)
+}
+
+func (l *labelIter) result() string {
+ if l.slice != nil {
+ return strings.Join(l.slice, ".")
+ }
+ return l.orig
+}
+
+func (l *labelIter) label() string {
+ if l.slice != nil {
+ return l.slice[l.i]
+ }
+ p := strings.IndexByte(l.orig[l.curStart:], '.')
+ l.curEnd = l.curStart + p
+ if p == -1 {
+ l.curEnd = len(l.orig)
+ }
+ return l.orig[l.curStart:l.curEnd]
+}
+
+// next sets the value to the next label. It skips the last label if it is empty.
+func (l *labelIter) next() {
+ l.i++
+ if l.slice != nil {
+ if l.i >= len(l.slice) || l.i == len(l.slice)-1 && l.slice[l.i] == "" {
+ l.curStart = len(l.orig)
+ }
+ } else {
+ l.curStart = l.curEnd + 1
+ if l.curStart == len(l.orig)-1 && l.orig[l.curStart] == '.' {
+ l.curStart = len(l.orig)
+ }
+ }
+}
+
+func (l *labelIter) set(s string) {
+ if l.slice == nil {
+ l.slice = strings.Split(l.orig, ".")
+ }
+ l.slice[l.i] = s
+}
+
+// acePrefix is the ASCII Compatible Encoding prefix.
+const acePrefix = "xn--"
+
+func (p *Profile) simplify(cat category) category {
+ switch cat {
+ case disallowedSTD3Mapped:
+ if p.useSTD3Rules {
+ cat = disallowed
+ } else {
+ cat = mapped
+ }
+ case disallowedSTD3Valid:
+ if p.useSTD3Rules {
+ cat = disallowed
+ } else {
+ cat = valid
+ }
+ case deviation:
+ if !p.transitional {
+ cat = valid
+ }
+ case validNV8, validXV8:
+ // TODO: handle V2008
+ cat = valid
+ }
+ return cat
+}
+
+func validateFromPunycode(p *Profile, s string) error {
+ if !norm.NFC.IsNormalString(s) {
+ return &labelError{s, "V1"}
+ }
+ // TODO: detect whether string may have to be normalized in the following
+ // loop.
+ for i := 0; i < len(s); {
+ v, sz := trie.lookupString(s[i:])
+ if sz == 0 {
+ return runeError(utf8.RuneError)
+ }
+ if c := p.simplify(info(v).category()); c != valid && c != deviation {
+ return &labelError{s, "V6"}
+ }
+ i += sz
+ }
+ return nil
+}
+
+const (
+ zwnj = "\u200c"
+ zwj = "\u200d"
+)
+
+type joinState int8
+
+const (
+ stateStart joinState = iota
+ stateVirama
+ stateBefore
+ stateBeforeVirama
+ stateAfter
+ stateFAIL
+)
+
+var joinStates = [][numJoinTypes]joinState{
+ stateStart: {
+ joiningL: stateBefore,
+ joiningD: stateBefore,
+ joinZWNJ: stateFAIL,
+ joinZWJ: stateFAIL,
+ joinVirama: stateVirama,
+ },
+ stateVirama: {
+ joiningL: stateBefore,
+ joiningD: stateBefore,
+ },
+ stateBefore: {
+ joiningL: stateBefore,
+ joiningD: stateBefore,
+ joiningT: stateBefore,
+ joinZWNJ: stateAfter,
+ joinZWJ: stateFAIL,
+ joinVirama: stateBeforeVirama,
+ },
+ stateBeforeVirama: {
+ joiningL: stateBefore,
+ joiningD: stateBefore,
+ joiningT: stateBefore,
+ },
+ stateAfter: {
+ joiningL: stateFAIL,
+ joiningD: stateBefore,
+ joiningT: stateAfter,
+ joiningR: stateStart,
+ joinZWNJ: stateFAIL,
+ joinZWJ: stateFAIL,
+ joinVirama: stateAfter, // no-op as we can't accept joiners here
+ },
+ stateFAIL: {
+ 0: stateFAIL,
+ joiningL: stateFAIL,
+ joiningD: stateFAIL,
+ joiningT: stateFAIL,
+ joiningR: stateFAIL,
+ joinZWNJ: stateFAIL,
+ joinZWJ: stateFAIL,
+ joinVirama: stateFAIL,
+ },
+}
+
+// validateLabel validates the criteria from Section 4.1. Item 1, 4, and 6 are
+// already implicitly satisfied by the overall implementation.
+func (p *Profile) validateLabel(s string) (err error) {
+ if s == "" {
+ if p.verifyDNSLength {
+ return &labelError{s, "A4"}
+ }
+ return nil
+ }
+ if !p.validateLabels {
+ return nil
+ }
+ trie := p.trie // p.validateLabels is only set if trie is set.
+ if len(s) > 4 && s[2] == '-' && s[3] == '-' {
+ return &labelError{s, "V2"}
+ }
+ if s[0] == '-' || s[len(s)-1] == '-' {
+ return &labelError{s, "V3"}
+ }
+ // TODO: merge the use of this in the trie.
+ v, sz := trie.lookupString(s)
+ x := info(v)
+ if x.isModifier() {
+ return &labelError{s, "V5"}
+ }
+ // Quickly return in the absence of zero-width (non) joiners.
+ if strings.Index(s, zwj) == -1 && strings.Index(s, zwnj) == -1 {
+ return nil
+ }
+ st := stateStart
+ for i := 0; ; {
+ jt := x.joinType()
+ if s[i:i+sz] == zwj {
+ jt = joinZWJ
+ } else if s[i:i+sz] == zwnj {
+ jt = joinZWNJ
+ }
+ st = joinStates[st][jt]
+ if x.isViramaModifier() {
+ st = joinStates[st][joinVirama]
+ }
+ if i += sz; i == len(s) {
+ break
+ }
+ v, sz = trie.lookupString(s[i:])
+ x = info(v)
+ }
+ if st == stateFAIL || st == stateAfter {
+ return &labelError{s, "C"}
+ }
+ return nil
+}
+
+func ascii(s string) bool {
+ for i := 0; i < len(s); i++ {
+ if s[i] >= utf8.RuneSelf {
+ return false
+ }
+ }
+ return true
+}