Re: lib/57172: LOG_MAKEPRI macro in sys/syslog.h defined incorrectly

[RVP <rvp%SDF.ORG@localhost>]

The following reply was made to PR lib/57172; it has been noted by GNATS.

From: RVP <rvp%SDF.ORG@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: lib/57172: LOG_MAKEPRI macro in sys/syslog.h defined
 incorrectly
Date: Fri, 2 Aug 2024 22:41:31 +0000 (UTC)

 I tripped over this same thing recently and made the patch below. It:
 
 a) Gets rid of LOG_MAKEPRI(). The only user in-tree is syslogd(8).
 
 b) Simplify INTERNAL_MARK.
 
 c) Adds a `-k' flag to not translate remote kern.* -> user.* (from
     FreeBSD).
 
     (src/lib/libc/gen/xsyslog.c forces this on all locally-generated
      kern.* messages. Maybe it shouldn't since syslogd does it anyway.)
 
 d) Fix syslogd:
     - SIGN_NUM_PRIVALS not defined anywhere.
     - Use the standard idiom to make `priority'.
 
 -RVP
 
 ---START patch---
 diff -urN a/src/crypto/external/bsd/heimdal/dist/lib/roken/syslog.hin b/src/crypto/external/bsd/heimdal/dist/lib/roken/syslog.hin
 --- a/src/crypto/external/bsd/heimdal/dist/lib/roken/syslog.hin	2011-04-13 18:15:43.000000000 +0000
 +++ b/src/crypto/external/bsd/heimdal/dist/lib/roken/syslog.hin	2024-07-28 21:53:12.784379077 +0000
 @@ -86,12 +86,11 @@
   #define	LOG_PRIMASK	0x07	/* mask to extract priority part (internal) */
   				/* extract priority */
   #define	LOG_PRI(p)	((p) & LOG_PRIMASK)
 -#define	LOG_MAKEPRI(fac, pri)	(((fac) << 3) | (pri))
 
   #ifdef SYSLOG_NAMES
   #define	INTERNAL_NOPRI	0x10	/* the "no priority" priority */
   				/* mark "facility" */
 -#define	INTERNAL_MARK	LOG_MAKEPRI(LOG_NFACILITIES, 0)
 +#define	INTERNAL_MARK	(LOG_NFACILITIES << 3)
   typedef struct _code {
   	char	*c_name;
   	int	c_val;
 diff -urN a/src/sys/sys/syslog.h b/src/sys/sys/syslog.h
 --- a/src/sys/sys/syslog.h	2024-07-12 03:31:26.109855531 +0000
 +++ b/src/sys/sys/syslog.h	2024-07-28 21:55:25.744625715 +0000
 @@ -62,12 +62,11 @@
   #define	LOG_PRIMASK	0x07	/* mask to extract priority part (internal) */
   				/* extract priority */
   #define	LOG_PRI(p)	((p) & LOG_PRIMASK)
 -#define	LOG_MAKEPRI(fac, pri)	(((fac) << 3) | (pri))
 
   #ifdef SYSLOG_NAMES
   #define	INTERNAL_NOPRI	0x10	/* the "no priority" priority */
   				/* mark "facility" */
 -#define	INTERNAL_MARK	LOG_MAKEPRI(LOG_NFACILITIES, 0)
 +#define	INTERNAL_MARK	(LOG_NFACILITIES << 3)
   typedef struct _code {
   	const char	*c_name;
   	int	c_val;
 diff -urN a/src/usr.sbin/syslogd/syslogd.8 b/src/usr.sbin/syslogd/syslogd.8
 --- a/src/usr.sbin/syslogd/syslogd.8	2022-11-08 01:43:09.000000000 +0000
 +++ b/src/usr.sbin/syslogd/syslogd.8	2024-07-28 23:12:21.623389569 +0000
 @@ -37,7 +37,7 @@
   .Nd log systems messages
   .Sh SYNOPSIS
   .Nm
 -.Op Fl nrSsTUvX
 +.Op Fl knrSsTUvX
   .Op Fl B Ar buffer_length
   .Op Fl b Ar bind_address
   .Op Fl d Op Oo Cm \&~ Oc Ns Ar what
 @@ -91,6 +91,15 @@
   Set GID to
   .Ar group
   after the sockets and log files have been opened.
 +.It Fl k
 +Disable the translation of (remote) messages received with facility
 +.Dq kern
 +to facility
 +.Dq user .
 +Usually the
 +.Dq kern
 +facility is reserved for messages read directly from
 +.Pa /dev/klog .
   .It Fl m Ar mark_interval
   Select the number of minutes between ``mark'' messages;
   the default is 20 minutes.
 diff -urN a/src/usr.sbin/syslogd/syslogd.c b/src/usr.sbin/syslogd/syslogd.c
 --- a/src/usr.sbin/syslogd/syslogd.c	2023-10-11 23:22:13.000000000 +0000
 +++ b/src/usr.sbin/syslogd/syslogd.c	2024-07-28 22:54:20.649653887 +0000
 @@ -205,6 +205,7 @@
   				 * this, it will only break some syslog-sign
   				 * configurations (e.g. with SG="0").
   				 */
 +bool	KernXlat = true;	/* translate kern.* -> user.* */
   char	appname[]   = "syslogd";/* the APPNAME for own messages */
   char   *include_pid;		/* include PID in own messages */
   char	include_pid_buf[11];
 @@ -319,7 +320,7 @@
   	/* should we set LC_TIME="C" to ensure correct timestamps&parsing? */
   	(void)setlocale(LC_ALL, "");
 
 -	while ((ch = getopt(argc, argv, "b:B:d::nsSf:m:o:p:P:ru:g:t:TUvX")) != -1)
 +	while ((ch = getopt(argc, argv, "b:B:d::knsSf:m:o:p:P:ru:g:t:TUvX")) != -1)
   		switch(ch) {
   		case 'b':
   			bindhostname = optarg;
 @@ -360,6 +361,9 @@
   			if (*group == '\0')
   				usage();
   			break;
 +		case 'k':		/* pass-thru (remote) kern.* */
 +			KernXlat = true;
 +			break;
   		case 'm':		/* mark interval */
   			MarkInterval = atoi(optarg) * 60;
   			break;
 @@ -557,7 +561,7 @@
   #if (IETF_NUM_PRIVALUES != (LOG_NFACILITIES<<3))
   	logerror("Warning: system defines %d priority values, but "
   	    "syslog-protocol/syslog-sign specify %d values",
 -	    LOG_NFACILITIES, SIGN_NUM_PRIVALS);
 +	    LOG_NFACILITIES, IETF_NUM_PRIVALUES >> 3);
   #endif
 
   	/*
 @@ -1549,12 +1553,12 @@
   		pri = DEFUPRI;
 
   	/*
 -	 * Don't allow users to log kernel messages.
 +	 * Don't (usually) allow users to log kernel messages.
   	 * NOTE: Since LOG_KERN == 0, this will also match
   	 *	 messages with no facility specified.
   	 */
 -	if ((pri & LOG_FACMASK) == LOG_KERN)
 -		pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri));
 +	if ((pri & LOG_FACMASK) == LOG_KERN && KernXlat)
 +		pri = LOG_USER | LOG_PRI(pri);
 
   	if (bsdsyslog) {
   		buffer = printline_bsdsyslog(hname, p, flags, pri);
 ---END patch---