Bugfix when no input file specified

This reverts commit 74ad307bd1.

.gitignore

@@ -1,2 +1,3 @@
 ./20211228134923.20211228151348
 tmpwrk
+godit

README.md

@@ -3,4 +3,8 @@
 Golang implementation of openBSM library  
 
 BSM is the audit format used by Darwin/FreeBSD  
-See http://www.trustedbsd.org/openbsm.html  
+See http://www.trustedbsd.org/openbsm.html  
+
+Include a binary "godit" which print audit logs in text or json format  
+Godit can read log files, /dev/auditpipe, or stdin with "-"  
+

capsicum.go

@@ -0,0 +1,242 @@
+// This is an implementation of libbsm
+// Copyright johan@nosd.in 2023
+//
+//go:build freebsd
+// +build freebsd
+
+//
+
+package main
+
+
+const (
+	// From freeebsd-src/sys/sys/caprights.h :
+	/*
+	 * The top two bits in the first element of the cr_rights[] array contain
+	 * total number of elements in the array - 2. This means if those two bits are
+	 * equal to 0, we have 2 array elements.
+	 * The top two bits in all remaining array elements should be 0.
+	 * The next five bits contain array index. Only one bit is used and bit position
+	 * in this five-bits range defines array index. This means there can be at most
+	 * five array elements.
+	 */
+	// So, I lazily chose to include index bit in following values
+	/* INDEX 0 */
+	
+	/*
+	 * General file I/O.
+	 */
+	/* Allows for openat(O_RDONLY), read(2), readv(2). */
+	CAP_READ      = 0x0200000000000001
+	/* Allows for openat(O_WRONLY | O_APPEND), write(2), writev(2). */
+	CAP_WRITE     = 0x0200000000000002
+	/* Allows for lseek(fd, 0, SEEK_CUR). */
+	CAP_SEEK_TELL = 0x0200000000000004
+	/* Allows for lseek(2). */
+	CAP_SEEK      = CAP_SEEK_TELL | 0x0200000000000008
+	/* Allows for aio_read(2), pread(2), preadv(2). */
+	CAP_PREAD     = (CAP_SEEK | CAP_READ)
+	/*
+	 * Allows for aio_write(2), openat(O_WRONLY) (without O_APPEND), pwrite(2),
+	 * pwritev(2).
+	 */
+	CAP_PWRITE    = (CAP_SEEK | CAP_WRITE)
+	/* Allows for mmap(PROT_NONE). */
+	CAP_MMAP      = 0x0200000000000010
+	/* Allows for mmap(PROT_READ). */
+	CAP_MMAP_R    = (CAP_MMAP | CAP_SEEK | CAP_READ)
+	/* Allows for mmap(PROT_WRITE). */
+	CAP_MMAP_W    = (CAP_MMAP | CAP_SEEK | CAP_WRITE)
+	/* Allows for mmap(PROT_EXEC). */
+	CAP_MMAP_X    = (CAP_MMAP | CAP_SEEK | 0x0200000000000020)
+	/* Allows for mmap(PROT_READ | PROT_WRITE). */
+	CAP_MMAP_RW   = (CAP_MMAP_R | CAP_MMAP_W)
+	/* Allows for mmap(PROT_READ | PROT_EXEC). */
+	CAP_MMAP_RX   = (CAP_MMAP_R | CAP_MMAP_X)
+	/* Allows for mmap(PROT_WRITE | PROT_EXEC). */
+	CAP_MMAP_WX   = (CAP_MMAP_W | CAP_MMAP_X)
+	/* Allows for mmap(PROT_READ | PROT_WRITE | PROT_EXEC). */
+	CAP_MMAP_RWX  = (CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X)
+	/* Allows for openat(O_CREAT). */
+	CAP_CREATE    = 0x0200000000000040
+	/* Allows for openat(O_EXEC) and fexecve(2) in turn. */
+	CAP_FEXECVE   = 0x0200000000000080
+	/* Allows for openat(O_SYNC), openat(O_FSYNC), fsync(2), aio_fsync(2). */
+	CAP_FSYNC     = 0x0200000000000100
+	/* Allows for openat(O_TRUNC), ftruncate(2). */
+	CAP_FTRUNCATE = 0x0200000000000200
+	
+	/* Lookups - used to constrain *at() calls. */
+	CAP_LOOKUP    = 0x0200000000000400
+	
+	/* VFS methods. */
+	/* Allows for fchdir(2). */
+	CAP_FCHDIR    = 0x0200000000000800
+	/* Allows for fchflags(2). */
+	CAP_FCHFLAGS  = 0x0200000000001000
+	/* Allows for fchflags(2) and chflagsat(2). */
+	CAP_CHFLAGSAT = (CAP_FCHFLAGS | CAP_LOOKUP)
+	/* Allows for fchmod(2). */
+	CAP_FCHMOD    = 0x0200000000002000
+	/* Allows for fchmod(2) and fchmodat(2). */
+	CAP_FCHMODAT  = (CAP_FCHMOD | CAP_LOOKUP)
+	/* Allows for fchown(2). */
+	CAP_FCHOWN    = 0x0200000000004000
+	/* Allows for fchown(2) and fchownat(2). */
+	CAP_FCHOWNAT  = (CAP_FCHOWN | CAP_LOOKUP)
+	/* Allows for fcntl(2). */
+	CAP_FCNTL     = 0x0200000000008000
+	/*
+	 * Allows for flock(2), openat(O_SHLOCK), openat(O_EXLOCK),
+	 * fcntl(F_SETLK_REMOTE), fcntl(F_SETLKW), fcntl(F_SETLK), fcntl(F_GETLK).
+	 */
+	CAP_FLOCK           = 0x0200000000010000
+	/* Allows for fpathconf(2). */
+	CAP_FPATHCONF       = 0x0200000000020000
+	/* Allows for UFS background-fsck operations. */
+	CAP_FSCK            = 0x0200000000040000
+	/* Allows for fstat(2). */
+	CAP_FSTAT           = 0x0200000000080000
+	/* Allows for fstat(2), fstatat(2) and faccessat(2). */
+	CAP_FSTATAT         = (CAP_FSTAT | CAP_LOOKUP)
+	/* Allows for fstatfs(2). */
+	CAP_FSTATFS         = 0x0200000000100000
+	/* Allows for futimens(2) and futimes(2). */
+	CAP_FUTIMES         = 0x0200000000200000
+	/* Allows for futimens(2), futimes(2), futimesat(2) and utimensat(2). */
+	CAP_FUTIMESAT       = (CAP_FUTIMES | CAP_LOOKUP)
+	/* Allows for linkat(2) (target directory descriptor). */
+	CAP_LINKAT_TARGET   = (CAP_LOOKUP | 0x0200000000400000)
+	/* Allows for mkdirat(2). */
+	CAP_MKDIRAT         = (CAP_LOOKUP | 0x0200000000800000)
+	/* Allows for mkfifoat(2). */
+	CAP_MKFIFOAT        = (CAP_LOOKUP | 0x0200000001000000)
+	/* Allows for mknodat(2). */
+	CAP_MKNODAT         = (CAP_LOOKUP | 0x0200000002000000)
+	/* Allows for renameat(2) (source directory descriptor). */
+	CAP_RENAMEAT_SOURCE = (CAP_LOOKUP | 0x0200000004000000)
+	/* Allows for symlinkat(2). */
+	CAP_SYMLINKAT       = (CAP_LOOKUP | 0x0200000008000000)
+	/*
+	 * Allows for unlinkat(2) and renameat(2) if destination object exists and
+	 * will be removed.
+	 */
+	CAP_UNLINKAT    = (CAP_LOOKUP | 0x0200000010000000)
+	
+	/* Socket operations. */
+	/* Allows for accept(2) and accept4(2). */
+	CAP_ACCEPT      = 0x0200000020000000
+	/* Allows for bind(2). */
+	CAP_BIND        = 0x0200000040000000
+	/* Allows for connect(2). */
+	CAP_CONNECT     = 0x0200000080000000
+	/* Allows for getpeername(2). */
+	CAP_GETPEERNAME = 0x0200000100000000
+	/* Allows for getsockname(2). */
+	CAP_GETSOCKNAME = 0x0200000200000000
+	/* Allows for getsockopt(2). */
+	CAP_GETSOCKOPT  = 0x0200000400000000
+	/* Allows for listen(2). */
+	CAP_LISTEN      = 0x0200000800000000
+	/* Allows for sctp_peeloff(2). */
+	CAP_PEELOFF     = 0x0300001000000000
+	CAP_RECV        = CAP_READ
+	CAP_SEND        = CAP_WRITE
+	/* Allows for setsockopt(2). */
+	CAP_SETSOCKOPT  = 0x0200002000000000
+	/* Allows for shutdown(2). */
+	CAP_SHUTDOWN    = 0x0200004000000000
+	
+	/* Allows for bindat(2) on a directory descriptor. */
+	CAP_BINDAT        = (CAP_LOOKUP | 0x0200008000000000)
+	/* Allows for connectat(2) on a directory descriptor. */
+	CAP_CONNECTAT     = (CAP_LOOKUP | 0x0200010000000000)
+	
+	/* Allows for linkat(2) (source directory descriptor). */
+	CAP_LINKAT_SOURCE   = (CAP_LOOKUP | 0x0200020000000000)
+	/* Allows for renameat(2) (target directory descriptor). */
+	CAP_RENAMEAT_TARGET = (CAP_LOOKUP | 0x0200040000000000)
+	
+	CAP_SOCK_CLIENT   = (CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT |
+		CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN)
+	CAP_SOCK_SERVER   = (CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME |
+		CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND |
+		CAP_SETSOCKOPT | CAP_SHUTDOWN)
+	
+	/* All used bits for index 0. */
+	CAP_ALL0       = 0x020007FFFFFFFFFF
+	
+	/* Available bits for index 0. */
+	CAP_UNUSED0_44 = 0x0200080000000000
+	/* ... */
+	CAP_UNUSED0_57 = 0x0300000000000000
+	
+	/* INDEX 1 */
+	
+	/* Mandatory Access Control. */
+	/* Allows for mac_get_fd(3). */
+	CAP_MAC_GET      = 0x0400000000000001
+	/* Allows for mac_set_fd(3). */
+	CAP_MAC_SET      = 0x0400000000000002
+	
+	/* Methods on semaphores. */
+	CAP_SEM_GETVALUE = 0x0400000000000004
+	CAP_SEM_POST     = 0x0400000000000008
+	CAP_SEM_WAIT     = 0x0400000000000010
+	
+	/* Allows select(2) and poll(2) on descriptor. */
+	CAP_EVENT        = 0x0400000000000020
+	/* Allows for kevent(2) on kqueue descriptor with eventlist != NULL. */
+	CAP_KQUEUE_EVENT = 0x0400000000000040
+	
+	/* Strange and powerful rights that should not be given lightly. */
+	/* Allows for ioctl(2). */
+	CAP_IOCTL        = 0x0400000000000080
+	CAP_TTYHOOK      = 0x0400000000000100
+	
+	/* Process management via process descriptors. */
+	/* Allows for pdgetpid(2). */
+	CAP_PDGETPID     = 0x0400000000000200
+	/*
+	 * Allows for pdwait4(2).
+	 *
+	 * XXX: this constant was imported unused, but is targeted to be implemented
+	 *      in the future (bug 235871).
+	 */
+	CAP_PDWAIT         = 0x0400000000000400
+	/* Allows for pdkill(2). */
+	CAP_PDKILL         = 0x0400000000000800
+	
+	/* Extended attributes. */
+	/* Allows for extattr_delete_fd(2). */
+	CAP_EXTATTR_DELETE = 0x0400000000001000
+	/* Allows for extattr_get_fd(2). */
+	CAP_EXTATTR_GET    = 0x0400000000002000
+	/* Allows for extattr_list_fd(2). */
+	CAP_EXTATTR_LIST   = 0x0400000000004000
+	/* Allows for extattr_set_fd(2). */
+	CAP_EXTATTR_SET    = 0x0400000000008000
+	
+	/* Access Control Lists. */
+	/* Allows for acl_valid_fd_np(3). */
+	CAP_ACL_CHECK      = 0x0400000000010000
+	/* Allows for acl_delete_fd_np(3). */
+	CAP_ACL_DELETE     = 0x0400000000020000
+	/* Allows for acl_get_fd(3) and acl_get_fd_np(3). */
+	CAP_ACL_GET        = 0x0400000000040000
+	/* Allows for acl_set_fd(3) and acl_set_fd_np(3). */
+	CAP_ACL_SET        = 0x0400000000080000
+	
+	/* Allows for kevent(2) on kqueue descriptor with changelist != NULL. */
+	CAP_KQUEUE_CHANGE  = 0x0400000000100000
+	
+	CAP_KQUEUE         = (CAP_KQUEUE_EVENT | CAP_KQUEUE_CHANGE)
+	
+	/* All used bits for index 1. */
+	CAP_ALL1           = 0x04000000001FFFFF
+	
+	/* Available bits for index 1. */
+	CAP_UNUSED1_22     = 0x0400000000200000
+	/* ... */
+	CAP_UNUSED1_57     = 0x0500000000000000
+)

libbsm.go

@@ -120,14 +120,16 @@ const (
 	AUT_PROCESS64_EX = 0x7d
 	AUT_IN_ADDR_EX   = 0x7e
 	AUT_SOCKET_EX    = 0x7f
+	// From sys/bsm/audit_record.h
 	AUT_SOCKINET32   = 0x80
 	AUT_SOCKINET128  = 0x81
 	AUT_SOCKUNIX     = 0x82
+	AUT_RIGHTS       = 0x83
 
 	// Display control
 	PRT_ONELINE        = 1
 	PRT_NORESOLVE_USER = 2
-	PRT_TIMESTAMP      = 4
+	PRT_TIMESYSLOG23   = 4
 	PRT_JSON           = 8
 )
 
@@ -373,6 +375,17 @@ type ZoneName struct {
 	Zone   []byte `json:"zone"`
 }
 
+type Capabilities struct {
+	Index uint8  `json:"index"`
+	Value uint64 `json:"value"`
+}
+
+type Rights struct {
+	Length uint8          `json:"length"` // Should it be nr of indices, or nr of capabilities? (in which case it should be calculated)
+					// Let it be nr of indices for now, we'll see when we will decode rights
+	Rights []Capabilities `json:"rights"`
+}
+
 /* Utilities */
 // users ID for resolution
 type user struct {
@@ -594,8 +607,8 @@ print_header32_tok(FILE *fp, tokenstr_t *tok, char *del, int oflags)
 */
 func (h *Header32) Print(file *os.File, delimiter string, flags int) {
 	var timeval string
-	if PRT_TIMESTAMP == flags&PRT_TIMESTAMP {
-		timeval = strconv.Itoa(int(h.S))
+	if PRT_TIMESYSLOG23 == flags&PRT_TIMESYSLOG23 {
+		timeval = time.Unix((int64)(h.S), 0).Add(time.Millisecond * (time.Duration)(h.Msec)).Format("2006-01-02T15:04:05.000Z07:00")
 	} else {
 		t := time.Unix((int64)(h.S), 0)
 		timeval = t.Format(time.UnixDate)
@@ -607,20 +620,37 @@ func (h *Header32) Print(file *os.File, delimiter string, flags int) {
 	}
 
 	if flags&PRT_JSON == PRT_JSON {
-		printable := struct {
-			Size    uint32 `json:"size"`           // Record byte count
-			Version uint8  `json:"version"`        // version # (uchar)
-			E_type  string `json:"event_type"`     // Event type
-			E_mod   uint16 `json:"event_modifier"` // Event modifier
-			Ts      string `json:"timestamp"`      // Seconds of time converted to data/hour/DST
-			Msec    uint32 `json:"msec"`           // Milliseconds of time
-		}{
-			Size:    h.Size,
-			Version: h.Version,
-			E_type:  evdesc,
-			E_mod:   h.E_mod,
-			Ts:      timeval,
-			Msec:    h.Msec,
+		var printable interface{}
+		if PRT_TIMESYSLOG23 == flags&PRT_TIMESYSLOG23 {
+			printable = struct {
+				Size    uint32 `json:"size"`           // Record byte count
+				Version uint8  `json:"version"`        // version # (uchar)
+				E_type  string `json:"event_type"`     // Event type
+				E_mod   uint16 `json:"event_modifier"` // Event modifier
+				Ts      string `json:"timestamp"`      // Seconds of time converted to RSYSLOG_SyslogProtocol23Format
+			}{
+				Size:    h.Size,
+				Version: h.Version,
+				E_type:  evdesc,
+				E_mod:   h.E_mod,
+				Ts:      timeval,
+			}
+		} else {
+			printable = struct {
+				Size    uint32 `json:"size"`           // Record byte count
+				Version uint8  `json:"version"`        // version # (uchar)
+				E_type  string `json:"event_type"`     // Event type
+				E_mod   uint16 `json:"event_modifier"` // Event modifier
+				Ts      string `json:"timestamp"`      // Seconds of time converted to data/hour/DST
+				Msec    uint32 `json:"msec"`           // Milliseconds of time
+			}{
+				Size:    h.Size,
+				Version: h.Version,
+				E_type:  evdesc,
+				E_mod:   h.E_mod,
+				Ts:      timeval,
+				Msec:    h.Msec,
+			}
 		}
 
 		j, err := json.Marshal(printable)
@@ -2972,14 +3002,136 @@ func (z *ZoneName) LoadFromBinary(rdr *bufio.Reader) error {
 }
 
 func (z *ZoneName) Print(file *os.File, delimiter string, flags int) {
-	fmt.Fprintf(file, "zone%s%s", delimiter, z.Zone)
-	if 0 == (flags & PRT_ONELINE) {
-		fmt.Fprintf(file, "\n")
+	if flags&PRT_JSON == PRT_JSON {
+		printable := struct {
+			Name   string `json:"name"`
+		}{
+			Name:   string(z.Zone),
+		}
+		j, err := json.Marshal(printable)
+		if err != nil {
+			// TODO
+			return
+		}
+		fmt.Fprintf(file, "\"zone\":")
+		fmt.Fprintf(file, "%s", j)
+		// ZoneName is always followed by something
+		fmt.Fprintf(file, ",")
 	} else {
-		fmt.Fprintf(file, "%s", delimiter)
+		fmt.Fprintf(file, "zone%s%s", delimiter, z.Zone)
+		if 0 == (flags & PRT_ONELINE) {
+			fmt.Fprintf(file, "\n")
+		} else {
+			fmt.Fprintf(file, "%s", delimiter)
+		}
 	}
 }
 
+func NewRights(r Rights) *Rights {
+	return &Rights{
+		Length: r.Length,
+		Rights: r.Rights,
+	}
+}
+
+func (r *Rights) GetType() uint8 {
+	return AUT_RIGHTS
+}
+
+func (r *Rights) getIndex(value uint64) uint8 {
+	var index uint8
+	idx := (value >> 57) & 0b11111
+	switch idx {
+		case 1:  index = 0
+		case 2:  index = 1
+		case 4:  index = 2
+		case 8:  index = 3
+		case 16: index = 4
+	}
+	return index
+}
+
+func (r *Rights) LoadFromBinary(rdr *bufio.Reader) error {
+	var firstVal uint64
+	var nextVal uint64
+	err := binary.Read(rdr, binary.BigEndian, &firstVal)
+	if err != nil {
+		return fmt.Errorf("Unable to read Rights.Length: %v", err)
+	}
+
+	/* The top two bits in the first element of the cr_rights[] array contain
+	* total number of elements in the array - 2 */
+	r.Length = uint8((firstVal >> 62) + 2)
+
+	rights := make([]Capabilities, r.Length)
+	capab := &Capabilities{
+		Index: r.getIndex(firstVal),
+		Value: firstVal,
+	}
+	rights[0] = *capab
+
+	for i := 1; i < int(r.Length); i++ {
+		err = binary.Read(rdr, binary.BigEndian, &nextVal)
+		if err != nil {
+			return fmt.Errorf("Unable to read Rights.Rights: %v", err)
+		} else {
+			capab := &Capabilities{
+				Index: r.getIndex(nextVal),
+				Value: nextVal,
+			}
+			rights[i] = *capab
+		}
+	}
+	r.Rights = rights[:r.Length]
+
+	return nil
+}
+
+// Override Capabilities Marshaling so we can print as hex
+func (c *Capabilities) MarshalJSON() ([]byte, error) {
+	val := fmt.Sprintf("%0.16x", c.Value)
+
+	type CapabilitiesJSON Capabilities
+	cJSON := struct {
+		Capabilities
+		Value string `json:"value"`
+	}{
+		Capabilities: Capabilities(*c),
+		Value:        val,
+	}
+
+	return json.Marshal(cJSON)
+}
+
+func (r *Rights) Print(file *os.File, delimiter string, flags int) {
+	if flags&PRT_JSON == PRT_JSON {
+		// Do not print Rights.Length, only capabilities array
+		j, err := json.Marshal(r.Rights)
+		if err != nil {
+			// TODO
+			return
+		}
+		fmt.Fprintf(file, "\"rights\":")
+		fmt.Fprintf(file, "%s", j)
+		// Rights is always followed by something
+		fmt.Fprintf(file, ",")
+	} else {
+		fmt.Fprintf(file, "rights%s%d", delimiter, r.Length)
+		for i:=0; i < int(r.Length); i++ {
+			if i < int(r.Length) {
+				fmt.Fprintf(file, "%s", delimiter)
+			}
+			fmt.Fprintf(file, "%d%s%0.16x", r.Rights[i].Index, delimiter, r.Rights[i].Value)
+		}
+		if 0 == (flags & PRT_ONELINE) {
+			fmt.Fprintf(file, "\n")
+		} else {
+			fmt.Fprintf(file, "%s", delimiter)
+		}
+	}
+}
+
+
 
 // From sys/bsm/audit_record.h
 func readRecordToStruct(reader *bufio.Reader) (Record, error) {
@@ -3149,6 +3301,13 @@ func readRecordToStruct(reader *bufio.Reader) (Record, error) {
 			return rec, fmt.Errorf("Unable to read: %v", err)
 		}
 		return NewZoneName(z), nil
+	case AUT_RIGHTS:
+		var r Rights
+		err := r.LoadFromBinary(reader)
+		if err != nil {
+			return rec, fmt.Errorf("Unable to read: %v", err)
+		}
+		return NewRights(r), nil
 	}
 
 	return rec, fmt.Errorf("Event type not supported: 0x%x", hdr[0])

main.go

@@ -33,7 +33,7 @@ import (
 )
 
 const (
-	version = "5.9.9a"
+	version = "0.6.1"
 )
 
 var (
@@ -48,13 +48,21 @@ func main() {
 	var flags int
 	var oneLine bool
 	var noUserResolve bool
-	var timestamp bool
+	var syslog23 bool
 	var json bool
 
-	pflag.BoolVarP(&oneLine, "oneline", "l", false, "Prints the entire record on the same line. If this option is not specified, every token is displayed on a different line.")
-	pflag.BoolVarP(&noUserResolve, "numeric", "n", false, "Do not convert user and group IDs to their names but leave in their numeric forms.")
+	pflag.BoolVarP(&oneLine, "oneline", "l", false, "Prints the entire record on the same line")
+	pflag.BoolVarP(&noUserResolve, "numeric", "n", false, "Do not convert user and group IDs to their names but leave in their numeric forms")
 	pflag.BoolVarP(&json, "json", "j", false, "Print compact json")
-	pflag.BoolVarP(&showVersion, "version", "V", false, "Show version then exit")
+	pflag.BoolVarP(&syslog23, "syslog23", "s", false, "Print time as \"2006-01-02T15:04:05.000Z07:00\", RFC339 with ms, also used on RSYSLOG_SyslogProtocol23Format. \"msec\" field will not be print in json output")
+	pflag.BoolVarP(&showVersion, "version", "V", false, "Show version and exit")
+
+	var Usage = func() {
+		fmt.Fprintf(os.Stderr, "Usage of \"%s [opts] auditfile\":\n", os.Args[0])
+		pflag.PrintDefaults()
+		fmt.Fprintf(os.Stderr, "Set auditfile to \"-\" to read stdin\n")
+	}
+	pflag.Usage = Usage
 
 	pflag.Parse()
 
@@ -68,14 +76,18 @@ func main() {
 	if noUserResolve {
 		flags = flags + PRT_NORESOLVE_USER
 	}
-	if timestamp {
-		flags = flags + PRT_TIMESTAMP
+	if syslog23 {
+		flags = flags + PRT_TIMESYSLOG23
 	}
 	if json {
 		flags |= PRT_JSON
 	}
 
 	args := os.Args
+	if len(os.Args) < 2 {
+		pflag.Usage()
+		os.Exit(1)
+	}
 	filename := args[len(args)-1]
 
 	var f *os.File