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-rw-r--r--vendor/gitea.com/go-chi/captcha/captcha.go248
1 files changed, 248 insertions, 0 deletions
diff --git a/vendor/gitea.com/go-chi/captcha/captcha.go b/vendor/gitea.com/go-chi/captcha/captcha.go
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index 0000000000..9d7e1f2ccb
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+++ b/vendor/gitea.com/go-chi/captcha/captcha.go
@@ -0,0 +1,248 @@
+// Copyright 2013 Beego Authors
+// Copyright 2014 The Macaron 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 captcha a middleware that provides captcha service for Macaron.
+package captcha
+
+import (
+ "fmt"
+ "html/template"
+ "image/color"
+ "net/http"
+ "path"
+ "strings"
+
+ "gitea.com/go-chi/cache"
+ "github.com/unknwon/com"
+)
+
+const _VERSION = "0.1.0"
+
+func Version() string {
+ return _VERSION
+}
+
+var (
+ defaultChars = []byte{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
+)
+
+// Captcha represents a captcha service.
+type Captcha struct {
+ Store cache.Cache
+ SubURL string
+ URLPrefix string
+ FieldIdName string
+ FieldCaptchaName string
+ StdWidth int
+ StdHeight int
+ ChallengeNums int
+ Expiration int64
+ CachePrefix string
+ ColorPalette color.Palette
+}
+
+// generate key string
+func (c *Captcha) key(id string) string {
+ return c.CachePrefix + id
+}
+
+// generate rand chars with default chars
+func (c *Captcha) genRandChars() string {
+ return string(com.RandomCreateBytes(c.ChallengeNums, defaultChars...))
+}
+
+// CreateHTML outputs HTML for display and fetch new captcha images.
+func (c *Captcha) CreateHTML() template.HTML {
+ value, err := c.CreateCaptcha()
+ if err != nil {
+ panic(fmt.Errorf("fail to create captcha: %v", err))
+ }
+ return template.HTML(fmt.Sprintf(`<input type="hidden" name="%[1]s" value="%[2]s">
+ <a class="captcha" href="javascript:" tabindex="-1">
+ <img onclick="this.src=('%[3]s%[4]s%[2]s.png?reload='+(new Date()).getTime())" class="captcha-img" src="%[3]s%[4]s%[2]s.png">
+ </a>`, c.FieldIdName, value, c.SubURL, c.URLPrefix))
+}
+
+// create a new captcha id
+func (c *Captcha) CreateCaptcha() (string, error) {
+ id := string(com.RandomCreateBytes(15))
+ if err := c.Store.Put(c.key(id), c.genRandChars(), c.Expiration); err != nil {
+ return "", err
+ }
+ return id, nil
+}
+
+// verify from a request
+func (c *Captcha) VerifyReq(req *http.Request) bool {
+ req.ParseForm()
+ return c.Verify(req.Form.Get(c.FieldIdName), req.Form.Get(c.FieldCaptchaName))
+}
+
+// direct verify id and challenge string
+func (c *Captcha) Verify(id string, challenge string) bool {
+ if len(challenge) == 0 || len(id) == 0 {
+ return false
+ }
+
+ var chars string
+
+ key := c.key(id)
+
+ if v, ok := c.Store.Get(key).(string); ok {
+ chars = v
+ } else {
+ return false
+ }
+
+ defer c.Store.Delete(key)
+
+ if len(chars) != len(challenge) {
+ return false
+ }
+
+ // verify challenge
+ for i, c := range []byte(chars) {
+ if c != challenge[i]-48 {
+ return false
+ }
+ }
+
+ return true
+}
+
+type Options struct {
+ // Suburl path. Default is empty.
+ SubURL string
+ // URL prefix of getting captcha pictures. Default is "/captcha/".
+ URLPrefix string
+ // Hidden input element ID. Default is "captcha_id".
+ FieldIdName string
+ // User input value element name in request form. Default is "captcha".
+ FieldCaptchaName string
+ // Challenge number. Default is 6.
+ ChallengeNums int
+ // Captcha image width. Default is 240.
+ Width int
+ // Captcha image height. Default is 80.
+ Height int
+ // Captcha expiration time in seconds. Default is 600.
+ Expiration int64
+ // Cache key prefix captcha characters. Default is "captcha_".
+ CachePrefix string
+ // ColorPalette holds a collection of primary colors used for
+ // the captcha's text. If not defined, a random color will be generated.
+ ColorPalette color.Palette
+}
+
+func prepareOptions(options []Options) Options {
+ var opt Options
+ if len(options) > 0 {
+ opt = options[0]
+ }
+
+ opt.SubURL = strings.TrimSuffix(opt.SubURL, "/")
+
+ // Defaults.
+ if len(opt.URLPrefix) == 0 {
+ opt.URLPrefix = "/captcha/"
+ } else if opt.URLPrefix[len(opt.URLPrefix)-1] != '/' {
+ opt.URLPrefix += "/"
+ }
+ if len(opt.FieldIdName) == 0 {
+ opt.FieldIdName = "captcha_id"
+ }
+ if len(opt.FieldCaptchaName) == 0 {
+ opt.FieldCaptchaName = "captcha"
+ }
+ if opt.ChallengeNums == 0 {
+ opt.ChallengeNums = 6
+ }
+ if opt.Width == 0 {
+ opt.Width = stdWidth
+ }
+ if opt.Height == 0 {
+ opt.Height = stdHeight
+ }
+ if opt.Expiration == 0 {
+ opt.Expiration = 600
+ }
+ if len(opt.CachePrefix) == 0 {
+ opt.CachePrefix = "captcha_"
+ }
+
+ return opt
+}
+
+// NewCaptcha initializes and returns a captcha with given options.
+func NewCaptcha(opts ...Options) *Captcha {
+ opt := prepareOptions(opts)
+ return &Captcha{
+ SubURL: opt.SubURL,
+ URLPrefix: opt.URLPrefix,
+ FieldIdName: opt.FieldIdName,
+ FieldCaptchaName: opt.FieldCaptchaName,
+ StdWidth: opt.Width,
+ StdHeight: opt.Height,
+ ChallengeNums: opt.ChallengeNums,
+ Expiration: opt.Expiration,
+ CachePrefix: opt.CachePrefix,
+ ColorPalette: opt.ColorPalette,
+ }
+}
+
+// Captchaer is a middleware that maps a captcha.Captcha service into the Macaron handler chain.
+// An single variadic captcha.Options struct can be optionally provided to configure.
+// This should be register after cache.Cacher.
+func Captchaer(cpt *Captcha) func(http.Handler) http.Handler {
+ return func(next http.Handler) http.Handler {
+ return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+ if strings.HasPrefix(req.URL.Path, cpt.URLPrefix) {
+ var chars string
+ id := path.Base(req.URL.Path)
+ if i := strings.Index(id, "."); i > -1 {
+ id = id[:i]
+ }
+ key := cpt.key(id)
+
+ reloads := req.URL.Query()["reload"]
+ // Reload captcha.
+ if len(reloads) > 0 && len(reloads[0]) > 0 {
+ chars = cpt.genRandChars()
+ if err := cpt.Store.Put(key, chars, cpt.Expiration); err != nil {
+ w.WriteHeader(500)
+ w.Write([]byte("captcha reload error"))
+ panic(fmt.Errorf("reload captcha: %v", err))
+ }
+ } else {
+ if v, ok := cpt.Store.Get(key).(string); ok {
+ chars = v
+ } else {
+ w.WriteHeader(404)
+ w.Write([]byte("captcha not found"))
+ return
+ }
+ }
+
+ w.WriteHeader(200)
+ if _, err := NewImage([]byte(chars), cpt.StdWidth, cpt.StdHeight, cpt.ColorPalette).WriteTo(w); err != nil {
+ panic(fmt.Errorf("write captcha: %v", err))
+ }
+ return
+ }
+
+ next.ServeHTTP(w, req)
+ })
+ }
+}