diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/pamldapd.go | 328 |
1 files changed, 0 insertions, 328 deletions
diff --git a/src/pamldapd.go b/src/pamldapd.go deleted file mode 100644 index 9685b3e..0000000 --- a/src/pamldapd.go +++ /dev/null @@ -1,328 +0,0 @@ -package main - -import ( - "encoding/json" - "errors" - "flag" - "fmt" - "github.com/msteinert/pam" - "github.com/nmcclain/asn1-ber" - "github.com/nmcclain/ldap" - "log" - "net" - "os" - "os/user" - "strings" -) - -type Backend struct { - ldap.Binder - ldap.Searcher - ldap.Closer - logger *log.Logger - Listen string - PAMServiceName string - PeopleDN string - GroupsDN string - BindAdminDN string - BindAdminPassword string -} - -func main() { - var configfile = flag.String("c", "pamldapd.json", "Configuration file") - var logfile = flag.String("l", "", "Log file (STDOUT if blank)") - flag.Parse() - var backend = Backend{} - { - confighandle, err := os.Open(*configfile) - if err != nil { - fmt.Printf("Could not read: %s\n", err) - os.Exit(1) - } - decoder := json.NewDecoder(confighandle) - if err := decoder.Decode(&backend); err != nil { - fmt.Printf("Could not decode configuration configfile %s: %s\n", *configfile, err) - confighandle.Close() - os.Exit(1) - } - confighandle.Close() - } - if *logfile == "" { - backend.logger = log.New(os.Stdout, "", log.LstdFlags) - } else { - loghandle, err := os.OpenFile(*logfile, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0600) - if err != nil { - fmt.Printf("Could not open log file: %s\n", err) - os.Exit(1) - } - defer loghandle.Close() - log.SetOutput(loghandle) - backend.logger = log.New(loghandle, "", log.LstdFlags) - } - - current_user, err := user.Current() - if err != nil { - fmt.Printf("Could not get current user: %s\n", err) - os.Exit(1) - } - if current_user.Uid != "0" { - backend.logger.Printf("WARNING: PAM authentication will fail because not running as root user") - } - - l := ldap.NewServer() - l.EnforceLDAP = true - l.BindFunc("", backend) - l.SearchFunc("", backend) - l.CloseFunc("", backend) - backend.logger.Printf("LDAP server listen: %s", backend.Listen) - if err := l.ListenAndServe(backend.Listen); err != nil { - backend.logger.Printf("LDAP server listen failed: %s", err.Error()) - os.Exit(1) - } -} - -func (b Backend) Bind(bindDN, bindSimplePw string, conn net.Conn) (resultCode ldap.LDAPResultCode, err error) { - var logger_title = fmt.Sprintf("Bind addr=%s bindDN=%s", conn.RemoteAddr().String(), bindDN) - b.logger.Printf("%s begin", logger_title) - if bindDN == b.BindAdminDN { - if bindSimplePw != b.BindAdminPassword { - return ldap.LDAPResultInvalidCredentials, errors.New("Password Incorrect") - } - b.logger.Printf("%s success as administrator", logger_title) - return ldap.LDAPResultSuccess, nil - } else { - var username string - if username, err = b.getUserNameFromBindDN(bindDN); err != nil { - return ldap.LDAPResultInvalidCredentials, err - } - if err := PAMAuth(b.PAMServiceName, username, bindSimplePw); err != nil { - return ldap.LDAPResultInvalidCredentials, err - } - b.logger.Printf("%s success as normal user", logger_title) - return ldap.LDAPResultSuccess, nil - } -} - -func (b Backend) Search(bindDN string, req ldap.SearchRequest, conn net.Conn) (result ldap.ServerSearchResult, err error) { - var logger_title = fmt.Sprintf("Search bindDN=%s baseDN=%s filter=%s addr=%s", bindDN, req.BaseDN, req.Filter, conn.RemoteAddr().String()) - b.logger.Printf("%s begin", logger_title) - filterObjectClass, err := ldap.GetFilterObjectClass(req.Filter) - if err != nil { - return ldap.ServerSearchResult{ResultCode: ldap.LDAPResultOperationsError}, fmt.Errorf("%s error parsing ObjectClass: %s", logger_title, req.Filter) - } - var username string - var user_entity_name string - if filterObjectClass == "posixaccount" || filterObjectClass == "" { - user_entity_name = "uid" - } else if filterObjectClass == "posixgroup" { - user_entity_name = "memberUid" - } else { - return ldap.ServerSearchResult{ResultCode: ldap.LDAPResultOperationsError}, fmt.Errorf("%s error: Filter does not contain objectclass=posixaccount nor objectclass=posixgroup", logger_title) - } - - if bindDN == b.BindAdminDN { - filterUid, err := GetFilterEntity(user_entity_name, req.Filter) - if err != nil { - return ldap.ServerSearchResult{ResultCode: ldap.LDAPResultOperationsError}, fmt.Errorf("%s error find condition uid: %s", logger_title, req.Filter) - } - if binddn_username, err := b.getUserNameFromBaseDN(req.BaseDN); err == nil { - username = binddn_username - } else { - username = filterUid - } - } else { - if username, err = b.getUserNameFromBindDN(bindDN); err != nil { - return ldap.ServerSearchResult{ResultCode: ldap.LDAPResultOperationsError}, err - } - } - if req.BaseDN == "" { - return ldap.ServerSearchResult{make([]*ldap.Entry, 0), []string{}, []ldap.Control{}, ldap.LDAPResultSuccess}, nil - } - var entry *ldap.Entry - if filterObjectClass == "posixaccount" || filterObjectClass == "" { - if entry, err = b.makeSearchEntryAccount("cn="+username+","+b.PeopleDN, username); err != nil { - return ldap.ServerSearchResult{ResultCode: ldap.LDAPResultOperationsError}, err - } - } else if filterObjectClass == "posixgroup" { - if entry, err = b.makeSearchEntryGroup(b.GroupsDN, username); err != nil { - return ldap.ServerSearchResult{ResultCode: ldap.LDAPResultOperationsError}, err - } - } else { - return ldap.ServerSearchResult{ResultCode: ldap.LDAPResultOperationsError}, fmt.Errorf("%s error: Filter does not contain objectclass=posixaccount nor objectclass=posixgroup", logger_title) - } - return ldap.ServerSearchResult{[]*ldap.Entry{entry}, []string{}, []ldap.Control{}, ldap.LDAPResultSuccess}, nil - - return ldap.ServerSearchResult{make([]*ldap.Entry, 0), []string{}, []ldap.Control{}, ldap.LDAPResultSuccess}, nil -} - -func (b Backend) Close(bindDN string, conn net.Conn) (err error) { - b.logger.Printf("Close addr=%s", conn.RemoteAddr().String()) - return nil -} - -func PAMAuth(serviceName, userName, passwd string) error { - t, err := pam.StartFunc(serviceName, userName, func(s pam.Style, msg string) (string, error) { - switch s { - case pam.PromptEchoOff: - return passwd, nil - case pam.PromptEchoOn, pam.ErrorMsg, pam.TextInfo: - return "", nil - } - return "", errors.New("Unrecognized PAM message style") - }) - - if err != nil { - return err - } - - if err = t.Authenticate(0); err != nil { - return err - } - - return nil -} - -func (b Backend) getUserNameFromBindDN(bindDN string) (username string, err error) { - if bindDN == "" { - return "", errors.New("bindDN not specified") - } - if !strings.HasSuffix(bindDN, ","+b.PeopleDN) { - return "", errors.New("bindDN not matched") - } - rest := strings.TrimSuffix(bindDN, ","+b.PeopleDN) - if rest == "" { - return "", errors.New("bindDN format error") - } - if strings.Contains(rest, ",") { - return "", errors.New("bindDN has too much entities") - } - if strings.HasPrefix(rest, "uid=") { - username = strings.TrimPrefix(rest, "uid=") - } else if strings.HasPrefix(rest, "cn=") { - username = strings.TrimPrefix(rest, "cn=") - } else { - return "", errors.New("bindDN contains no cn/uid entry") - } - return username, nil -} - -func (b Backend) getUserNameFromBaseDN(baseDN string) (username string, err error) { - if baseDN == "" { - return "", errors.New("baseDN not specified") - } - if !strings.HasSuffix(baseDN, ","+b.PeopleDN) { - return "", errors.New("baseDN not matched") - } - rest := strings.TrimSuffix(baseDN, ","+b.PeopleDN) - if rest == "" { - return "", errors.New("baseDN format error") - } - if strings.Contains(rest, ",") { - return "", errors.New("baseDN has too much entities") - } - if strings.HasPrefix(rest, "uid=") { - username = strings.TrimPrefix(rest, "uid=") - } else if strings.HasPrefix(rest, "cn=") { - username = strings.TrimPrefix(rest, "cn=") - } else { - return "", errors.New("baseDN contains no cn/uid entry") - } - return username, nil -} - -func (b Backend) makeSearchEntryAccount(dn string, username string) (entry *ldap.Entry, err error) { - attrs := []*ldap.EntryAttribute{} - var u *user.User - if u, err = user.Lookup(username); err != nil { - return entry, err - } - attrs = append(attrs, &ldap.EntryAttribute{"objectClass", []string{"posixAccount"}}) - attrs = append(attrs, &ldap.EntryAttribute{"cn", []string{username}}) - attrs = append(attrs, &ldap.EntryAttribute{"uid", []string{username}}) - attrs = append(attrs, &ldap.EntryAttribute{"uidNumber", []string{u.Uid}}) - attrs = append(attrs, &ldap.EntryAttribute{"givenName", []string{u.Name}}) - attrs = append(attrs, &ldap.EntryAttribute{"gidNumber", []string{u.Gid}}) - attrs = append(attrs, &ldap.EntryAttribute{"homeDirectory", []string{u.HomeDir}}) - - entry = &ldap.Entry{dn, attrs} - return entry, nil -} - -func (b Backend) makeSearchEntryGroup(basedn string, username string) (entry *ldap.Entry, err error) { - attrs := []*ldap.EntryAttribute{} - var ( - u *user.User - g *user.Group - ) - if u, err = user.Lookup(username); err != nil { - return entry, err - } - if g, err = user.LookupGroupId(u.Gid); err != nil { - return entry, err - } - - attrs = append(attrs, &ldap.EntryAttribute{"objectClass", []string{"posixGroup"}}) - attrs = append(attrs, &ldap.EntryAttribute{"cn", []string{g.Name}}) - attrs = append(attrs, &ldap.EntryAttribute{"gidNumber", []string{u.Gid}}) - attrs = append(attrs, &ldap.EntryAttribute{"memberUid", []string{username}}) - - dn := "cn=" + g.Name + "," + basedn - entry = &ldap.Entry{dn, attrs} - return entry, nil -} - -func GetFilterEntity(entity string, filter string) (string, error) { - f, err := ldap.CompileFilter(filter) - if err != nil { - return "", err - } - return parseFilterEntity(entity, f) -} - -func parseFilterEntity(entity string, f *ber.Packet) (string, error) { - foundEntity := "" - switch ldap.FilterMap[f.Tag] { - case "Equality Match": - if len(f.Children) != 2 { - return "", errors.New("Equality match must have only two children") - } - attribute := strings.ToLower(f.Children[0].Value.(string)) - value := f.Children[1].Value.(string) - if attribute == entity { - foundEntity = strings.ToLower(value) - } - case "And": - for _, child := range f.Children { - subType, err := parseFilterEntity(entity, child) - if err != nil { - return "", err - } - if len(subType) > 0 { - foundEntity = subType - } - } - case "Or": - for _, child := range f.Children { - subType, err := parseFilterEntity(entity, child) - if err != nil { - return "", err - } - if len(subType) > 0 { - foundEntity = subType - } - } - case "Not": - if len(f.Children) != 1 { - return "", errors.New("Not filter must have only one child") - } - subType, err := parseFilterEntity(entity, f.Children[0]) - if err != nil { - return "", err - } - if len(subType) > 0 { - foundEntity = subType - } - - } - return strings.ToLower(foundEntity), nil -} |