internal: move packages under this directory (#5836)

* Rename pkg -> internal

* Rename routes -> route

* Move route -> internal/route

* Rename models -> db

* Move db -> internal/db

* Fix route2 -> route

* Move cmd -> internal/cmd

* Bump version

2 files changed, 447 insertions, 0 deletions

diff --git a/internal/auth/ldap/README.md b/internal/auth/ldap/README.md
new file mode 100644
index 00000000..bc357e96
--- /dev/null
+++ b/internal/auth/ldap/README.md
@@ -0,0 +1,119 @@
+Gogs LDAP Authentication Module
+===============================
+
+## About
+
+This authentication module attempts to authorize and authenticate a user
+against an LDAP server. It provides two methods of authentication: LDAP via
+BindDN, and LDAP simple authentication.
+
+LDAP via BindDN functions like most LDAP authentication systems. First, it
+queries the LDAP server using a Bind DN and searches for the user that is
+attempting to sign in. If the user is found, the module attempts to bind to the
+server using the user's supplied credentials. If this succeeds, the user has
+been authenticated, and their account information is retrieved and passed to the
+Gogs login infrastructure.
+
+LDAP simple authentication does not utilize a Bind DN. Instead, it binds
+directly with the LDAP server using the user's supplied credentials. If the bind
+succeeds and no filter rules out the user, the user is authenticated.
+
+LDAP via BindDN is recommended for most users. By using a Bind DN, the server
+can perform authorization by restricting which entries the Bind DN account can
+read. Furthermore, using a Bind DN with reduced permissions can reduce security risk
+in the face of application bugs.
+
+## Usage
+
+To use this module, add an LDAP authentication source via the Authentications
+section in the admin panel. Both the LDAP via BindDN and the simple auth LDAP
+share the following fields:
+
+* Authorization Name **(required)**
+    * A name to assign to the new method of authorization.
+
+* Host **(required)**
+    * The address where the LDAP server can be reached.
+    * Example: mydomain.com
+
+* Port **(required)**
+    * The port to use when connecting to the server.
+    * Example: 636
+
+* Enable TLS Encryption (optional)
+    * Whether to use TLS when connecting to the LDAP server.
+
+* Admin Filter (optional)
+    * An LDAP filter specifying if a user should be given administrator
+      privileges. If a user accounts passes the filter, the user will be
+      privileged as an administrator.
+    * Example: (objectClass=adminAccount)
+
+* First name attribute (optional)
+    * The attribute of the user's LDAP record containing the user's first name.
+      This will be used to populate their account information.
+    * Example: givenName
+
+* Surname attribute (optional)
+    * The attribute of the user's LDAP record containing the user's surname This
+      will be used to populate their account information.
+    * Example: sn
+
+* E-mail attribute **(required)**
+    * The attribute of the user's LDAP record containing the user's email
+      address. This will be used to populate their account information.
+    * Example: mail
+
+**LDAP via BindDN** adds the following fields:
+
+* Bind DN (optional)
+    * The DN to bind to the LDAP server with when searching for the user. This
+      may be left blank to perform an anonymous search.
+    * Example: cn=Search,dc=mydomain,dc=com
+
+* Bind Password (optional)
+    * The password for the Bind DN specified above, if any. _Note: The password
+      is stored in plaintext at the server. As such, ensure that your Bind DN
+      has as few privileges as possible._
+
+* User Search Base **(required)**
+    * The LDAP base at which user accounts will be searched for.
+    * Example: ou=Users,dc=mydomain,dc=com
+
+* User Filter **(required)**
+    * An LDAP filter declaring how to find the user record that is attempting to
+      authenticate. The '%s' matching parameter will be substituted with the
+      user's username.
+    * Example: (&(objectClass=posixAccount)(uid=%s))
+
+**LDAP using simple auth** adds the following fields:
+
+* User DN **(required)**
+    * A template to use as the user's DN. The `%s` matching parameter will be
+      substituted with the user's username.
+    * Example: cn=%s,ou=Users,dc=mydomain,dc=com
+    * Example: uid=%s,ou=Users,dc=mydomain,dc=com
+
+* User Filter **(required)**
+    * An LDAP filter declaring when a user should be allowed to log in. The `%s`
+      matching parameter will be substituted with the user's username.
+    * Example: (&(objectClass=posixAccount)(cn=%s))
+    * Example: (&(objectClass=posixAccount)(uid=%s))
+
+**Verify group membership in LDAP** uses the following fields:
+
+* Group Search Base (optional)
+    * The LDAP DN used for groups.
+    * Example: ou=group,dc=mydomain,dc=com
+
+* Group Name Filter (optional)
+    * An LDAP filter declaring how to find valid groups in the above DN.
+    * Example: (|(cn=gogs_users)(cn=admins))
+
+* User Attribute in Group (optional)
+    * Which user LDAP attribute is listed in the group.
+    * Example: uid
+
+* Group Attribute for User (optional)
+    * Which group LDAP attribute contains an array above user attribute names.
+    * Example: memberUid
diff --git a/internal/auth/ldap/ldap.go b/internal/auth/ldap/ldap.go
new file mode 100644
index 00000000..e88cef77
--- /dev/null
+++ b/internal/auth/ldap/ldap.go
@@ -0,0 +1,328 @@
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+// Package ldap provide functions & structure to query a LDAP ldap directory
+// For now, it's mainly tested again an MS Active Directory service, see README.md for more information
+package ldap
+
+import (
+	"crypto/tls"
+	"fmt"
+	"strings"
+
+	log "gopkg.in/clog.v1"
+	"gopkg.in/ldap.v2"
+)
+
+type SecurityProtocol int
+
+// Note: new type must be added at the end of list to maintain compatibility.
+const (
+	SECURITY_PROTOCOL_UNENCRYPTED SecurityProtocol = iota
+	SECURITY_PROTOCOL_LDAPS
+	SECURITY_PROTOCOL_START_TLS
+)
+
+// Basic LDAP authentication service
+type Source struct {
+	Host              string // LDAP host
+	Port              int    // port number
+	SecurityProtocol  SecurityProtocol
+	SkipVerify        bool
+	BindDN            string `ini:"bind_dn,omitempty"` // DN to bind with
+	BindPassword      string `ini:",omitempty"`        // Bind DN password
+	UserBase          string `ini:",omitempty"`        // Base search path for users
+	UserDN            string `ini:"user_dn,omitempty"` // Template for the DN of the user for simple auth
+	AttributeUsername string // Username attribute
+	AttributeName     string // First name attribute
+	AttributeSurname  string // Surname attribute
+	AttributeMail     string // E-mail attribute
+	AttributesInBind  bool   // fetch attributes in bind context (not user)
+	Filter            string // Query filter to validate entry
+	AdminFilter       string // Query filter to check if user is admin
+	GroupEnabled      bool   // if the group checking is enabled
+	GroupDN           string `ini:"group_dn"` // Group Search Base
+	GroupFilter       string // Group Name Filter
+	GroupMemberUID    string `ini:"group_member_uid"` // Group Attribute containing array of UserUID
+	UserUID           string `ini:"user_uid"`         // User Attribute listed in Group
+}
+
+func (ls *Source) sanitizedUserQuery(username string) (string, bool) {
+	// See http://tools.ietf.org/search/rfc4515
+	badCharacters := "\x00()*\\"
+	if strings.ContainsAny(username, badCharacters) {
+		log.Trace("LDAP: Username contains invalid query characters: %s", username)
+		return "", false
+	}
+
+	return strings.Replace(ls.Filter, "%s", username, -1), true
+}
+
+func (ls *Source) sanitizedUserDN(username string) (string, bool) {
+	// See http://tools.ietf.org/search/rfc4514: "special characters"
+	badCharacters := "\x00()*\\,='\"#+;<>"
+	if strings.ContainsAny(username, badCharacters) || strings.HasPrefix(username, " ") || strings.HasSuffix(username, " ") {
+		log.Trace("LDAP: Username contains invalid query characters: %s", username)
+		return "", false
+	}
+
+	return strings.Replace(ls.UserDN, "%s", username, -1), true
+}
+
+func (ls *Source) sanitizedGroupFilter(group string) (string, bool) {
+	// See http://tools.ietf.org/search/rfc4515
+	badCharacters := "\x00*\\"
+	if strings.ContainsAny(group, badCharacters) {
+		log.Trace("LDAP: Group filter invalid query characters: %s", group)
+		return "", false
+	}
+
+	return group, true
+}
+
+func (ls *Source) sanitizedGroupDN(groupDn string) (string, bool) {
+	// See http://tools.ietf.org/search/rfc4514: "special characters"
+	badCharacters := "\x00()*\\'\"#+;<>"
+	if strings.ContainsAny(groupDn, badCharacters) || strings.HasPrefix(groupDn, " ") || strings.HasSuffix(groupDn, " ") {
+		log.Trace("LDAP: Group DN contains invalid query characters: %s", groupDn)
+		return "", false
+	}
+
+	return groupDn, true
+}
+
+func (ls *Source) findUserDN(l *ldap.Conn, name string) (string, bool) {
+	log.Trace("Search for LDAP user: %s", name)
+	if len(ls.BindDN) > 0 && len(ls.BindPassword) > 0 {
+		// Replace placeholders with username
+		bindDN := strings.Replace(ls.BindDN, "%s", name, -1)
+		err := l.Bind(bindDN, ls.BindPassword)
+		if err != nil {
+			log.Trace("LDAP: Failed to bind as BindDN '%s': %v", bindDN, err)
+			return "", false
+		}
+		log.Trace("LDAP: Bound as BindDN: %s", bindDN)
+	} else {
+		log.Trace("LDAP: Proceeding with anonymous LDAP search")
+	}
+
+	// A search for the user.
+	userFilter, ok := ls.sanitizedUserQuery(name)
+	if !ok {
+		return "", false
+	}
+
+	log.Trace("LDAP: Searching for DN using filter '%s' and base '%s'", userFilter, ls.UserBase)
+	search := ldap.NewSearchRequest(
+		ls.UserBase, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0,
+		false, userFilter, []string{}, nil)
+
+	// Ensure we found a user
+	sr, err := l.Search(search)
+	if err != nil || len(sr.Entries) < 1 {
+		log.Trace("LDAP: Failed search using filter '%s': %v", userFilter, err)
+		return "", false
+	} else if len(sr.Entries) > 1 {
+		log.Trace("LDAP: Filter '%s' returned more than one user", userFilter)
+		return "", false
+	}
+
+	userDN := sr.Entries[0].DN
+	if userDN == "" {
+		log.Error(2, "LDAP: Search was successful, but found no DN!")
+		return "", false
+	}
+
+	return userDN, true
+}
+
+func dial(ls *Source) (*ldap.Conn, error) {
+	log.Trace("LDAP: Dialing with security protocol '%v' without verifying: %v", ls.SecurityProtocol, ls.SkipVerify)
+
+	tlsCfg := &tls.Config{
+		ServerName:         ls.Host,
+		InsecureSkipVerify: ls.SkipVerify,
+	}
+	if ls.SecurityProtocol == SECURITY_PROTOCOL_LDAPS {
+		return ldap.DialTLS("tcp", fmt.Sprintf("%s:%d", ls.Host, ls.Port), tlsCfg)
+	}
+
+	conn, err := ldap.Dial("tcp", fmt.Sprintf("%s:%d", ls.Host, ls.Port))
+	if err != nil {
+		return nil, fmt.Errorf("Dial: %v", err)
+	}
+
+	if ls.SecurityProtocol == SECURITY_PROTOCOL_START_TLS {
+		if err = conn.StartTLS(tlsCfg); err != nil {
+			conn.Close()
+			return nil, fmt.Errorf("StartTLS: %v", err)
+		}
+	}
+
+	return conn, nil
+}
+
+func bindUser(l *ldap.Conn, userDN, passwd string) error {
+	log.Trace("Binding with userDN: %s", userDN)
+	err := l.Bind(userDN, passwd)
+	if err != nil {
+		log.Trace("LDAP authentication failed for '%s': %v", userDN, err)
+		return err
+	}
+	log.Trace("Bound successfully with userDN: %s", userDN)
+	return err
+}
+
+// searchEntry : search an LDAP source if an entry (name, passwd) is valid and in the specific filter
+func (ls *Source) SearchEntry(name, passwd string, directBind bool) (string, string, string, string, bool, bool) {
+	// See https://tools.ietf.org/search/rfc4513#section-5.1.2
+	if len(passwd) == 0 {
+		log.Trace("authentication failed for '%s' with empty password", name)
+		return "", "", "", "", false, false
+	}
+	l, err := dial(ls)
+	if err != nil {
+		log.Error(2, "LDAP connect failed for '%s': %v", ls.Host, err)
+		return "", "", "", "", false, false
+	}
+	defer l.Close()
+
+	var userDN string
+	if directBind {
+		log.Trace("LDAP will bind directly via UserDN template: %s", ls.UserDN)
+
+		var ok bool
+		userDN, ok = ls.sanitizedUserDN(name)
+		if !ok {
+			return "", "", "", "", false, false
+		}
+	} else {
+		log.Trace("LDAP will use BindDN")
+
+		var found bool
+		userDN, found = ls.findUserDN(l, name)
+		if !found {
+			return "", "", "", "", false, false
+		}
+	}
+
+	if directBind || !ls.AttributesInBind {
+		// binds user (checking password) before looking-up attributes in user context
+		err = bindUser(l, userDN, passwd)
+		if err != nil {
+			return "", "", "", "", false, false
+		}
+	}
+
+	userFilter, ok := ls.sanitizedUserQuery(name)
+	if !ok {
+		return "", "", "", "", false, false
+	}
+
+	log.Trace("Fetching attributes '%v', '%v', '%v', '%v', '%v' with filter '%s' and base '%s'",
+		ls.AttributeUsername, ls.AttributeName, ls.AttributeSurname, ls.AttributeMail, ls.UserUID, userFilter, userDN)
+	search := ldap.NewSearchRequest(
+		userDN, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false, userFilter,
+		[]string{ls.AttributeUsername, ls.AttributeName, ls.AttributeSurname, ls.AttributeMail, ls.UserUID},
+		nil)
+
+	sr, err := l.Search(search)
+	if err != nil {
+		log.Error(2, "LDAP: User search failed: %v", err)
+		return "", "", "", "", false, false
+	} else if len(sr.Entries) < 1 {
+		if directBind {
+			log.Trace("LDAP: User filter inhibited user login")
+		} else {
+			log.Trace("LDAP: User search failed: 0 entries")
+		}
+
+		return "", "", "", "", false, false
+	}
+
+	username := sr.Entries[0].GetAttributeValue(ls.AttributeUsername)
+	firstname := sr.Entries[0].GetAttributeValue(ls.AttributeName)
+	surname := sr.Entries[0].GetAttributeValue(ls.AttributeSurname)
+	mail := sr.Entries[0].GetAttributeValue(ls.AttributeMail)
+	uid := sr.Entries[0].GetAttributeValue(ls.UserUID)
+
+	// Check group membership
+	if ls.GroupEnabled {
+		groupFilter, ok := ls.sanitizedGroupFilter(ls.GroupFilter)
+		if !ok {
+			return "", "", "", "", false, false
+		}
+		groupDN, ok := ls.sanitizedGroupDN(ls.GroupDN)
+		if !ok {
+			return "", "", "", "", false, false
+		}
+
+		log.Trace("LDAP: Fetching groups '%v' with filter '%s' and base '%s'", ls.GroupMemberUID, groupFilter, groupDN)
+		groupSearch := ldap.NewSearchRequest(
+			groupDN, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false, groupFilter,
+			[]string{ls.GroupMemberUID},
+			nil)
+
+		srg, err := l.Search(groupSearch)
+		if err != nil {
+			log.Error(2, "LDAP: Group search failed: %v", err)
+			return "", "", "", "", false, false
+		} else if len(srg.Entries) < 1 {
+			log.Trace("LDAP: Group search returned no entries")
+			return "", "", "", "", false, false
+		}
+
+		isMember := false
+		if ls.UserUID == "dn" {
+			for _, group := range srg.Entries {
+				for _, member := range group.GetAttributeValues(ls.GroupMemberUID) {
+					if member == sr.Entries[0].DN {
+						isMember = true
+					}
+				}
+			}
+		} else {
+			for _, group := range srg.Entries {
+				for _, member := range group.GetAttributeValues(ls.GroupMemberUID) {
+					if member == uid {
+						isMember = true
+					}
+				}
+			}
+		}
+
+		if !isMember {
+			log.Trace("LDAP: Group membership test failed [username: %s, group_member_uid: %s, user_uid: %s", username, ls.GroupMemberUID, uid)
+			return "", "", "", "", false, false
+		}
+	}
+
+	isAdmin := false
+	if len(ls.AdminFilter) > 0 {
+		log.Trace("Checking admin with filter '%s' and base '%s'", ls.AdminFilter, userDN)
+		search = ldap.NewSearchRequest(
+			userDN, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false, ls.AdminFilter,
+			[]string{ls.AttributeName},
+			nil)
+
+		sr, err = l.Search(search)
+		if err != nil {
+			log.Error(2, "LDAP: Admin search failed: %v", err)
+		} else if len(sr.Entries) < 1 {
+			log.Trace("LDAP: Admin search returned no entries")
+		} else {
+			isAdmin = true
+		}
+	}
+
+	if !directBind && ls.AttributesInBind {
+		// binds user (checking password) after looking-up attributes in BindDN context
+		err = bindUser(l, userDN, passwd)
+		if err != nil {
+			return "", "", "", "", false, false
+		}
+	}
+
+	return username, firstname, surname, mail, isAdmin, true
+}