Added support for gopher URLs. (#14749)

* Added support for gopher URLs.

* Add setting and make this user settable instead

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: Andrew Thornton <art27@cantab.net>

modules/setting/service.go

@@ -6,6 +6,7 @@ package setting
 
 import (
 	"regexp"
+	"strings"
 	"time"
 
 	"code.gitea.io/gitea/modules/log"
@@ -55,6 +56,7 @@ var Service struct {
 	AutoWatchOnChanges                      bool
 	DefaultOrgMemberVisible                 bool
 	UserDeleteWithCommentsMaxTime           time.Duration
+	ValidSiteURLSchemes                     []string
 
 	// OpenID settings
 	EnableOpenIDSignIn bool
@@ -120,6 +122,16 @@ func newService() {
 	Service.DefaultOrgVisibilityMode = structs.VisibilityModes[Service.DefaultOrgVisibility]
 	Service.DefaultOrgMemberVisible = sec.Key("DEFAULT_ORG_MEMBER_VISIBLE").MustBool()
 	Service.UserDeleteWithCommentsMaxTime = sec.Key("USER_DELETE_WITH_COMMENTS_MAX_TIME").MustDuration(0)
+	sec.Key("VALID_SITE_URL_SCHEMES").MustString("http,https")
+	Service.ValidSiteURLSchemes = sec.Key("VALID_SITE_URL_SCHEMES").Strings(",")
+	schemes := make([]string, len(Service.ValidSiteURLSchemes))
+	for _, scheme := range Service.ValidSiteURLSchemes {
+		scheme = strings.ToLower(strings.TrimSpace(scheme))
+		if scheme != "" {
+			schemes = append(schemes, scheme)
+		}
+	}
+	Service.ValidSiteURLSchemes = schemes
 
 	if err := Cfg.Section("service.explore").MapTo(&Service.Explore); err != nil {
 		log.Fatal("Failed to map service.explore settings: %v", err)

modules/validation/binding.go

@@ -55,6 +55,7 @@ func CheckGitRefAdditionalRulesValid(name string) bool {
 func AddBindingRules() {
 	addGitRefNameBindingRule()
 	addValidURLBindingRule()
+	addValidSiteURLBindingRule()
 	addGlobPatternRule()
 	addRegexPatternRule()
 	addGlobOrRegexPatternRule()
@@ -102,6 +103,24 @@ func addValidURLBindingRule() {
 	})
 }
 
+func addValidSiteURLBindingRule() {
+	// URL validation rule
+	binding.AddRule(&binding.Rule{
+		IsMatch: func(rule string) bool {
+			return strings.HasPrefix(rule, "ValidSiteUrl")
+		},
+		IsValid: func(errs binding.Errors, name string, val interface{}) (bool, binding.Errors) {
+			str := fmt.Sprintf("%v", val)
+			if len(str) != 0 && !IsValidSiteURL(str) {
+				errs.Add([]string{name}, binding.ERR_URL, "Url")
+				return false, errs
+			}
+
+			return true, errs
+		},
+	})
+}
+
 func addGlobPatternRule() {
 	binding.AddRule(&binding.Rule{
 		IsMatch: func(rule string) bool {

modules/validation/helpers.go

@@ -52,6 +52,25 @@ func IsValidURL(uri string) bool {
 	return true
 }
 
+// IsValidSiteURL checks if URL is valid
+func IsValidSiteURL(uri string) bool {
+	u, err := url.ParseRequestURI(uri)
+	if err != nil {
+		return false
+	}
+
+	if !validPort(portOnly(u.Host)) {
+		return false
+	}
+
+	for _, scheme := range setting.Service.ValidSiteURLSchemes {
+		if scheme == u.Scheme {
+			return true
+		}
+	}
+	return false
+}
+
 // IsAPIURL checks if URL is current Gitea instance API URL
 func IsAPIURL(uri string) bool {
 	return strings.HasPrefix(strings.ToLower(uri), strings.ToLower(setting.AppURL+"api"))