From: Martijn van Duren <openbsd+tech@list.imperialat.at>
Subject: smtpd: better default syslog tag for filters
To: tech@openbsd.org
Date: Fri, 20 Mar 2026 11:43:03 +0100

EHLO,

While reasonable for my initial testing, having the tag be set to the
name of the processor, instead of the name of the command might be
a better default choice. This also shaves of a bit of code.

OK?

martijn@

diff /usr/src
path + /usr/src
commit - a9b792a8dce6145cbe526f847ad0f84cf9afd558
blob - 02313181cc00765d3a2051ab92cd81ca15114961
file + usr.sbin/smtpd/parse.y
--- usr.sbin/smtpd/parse.y
+++ usr.sbin/smtpd/parse.y
@@ -454,7 +454,7 @@ PROC STRING STRING {
 	processor->command = $3;
 } proc_params {
 	if (!processor->tag)
-		processor->tag = processor_maketag(processor->command);
+		processor->tag = processor_maketag($2);
 	dict_set(conf->sc_filter_processes_dict, $2, processor);
 	processor = NULL;
 }
@@ -1956,7 +1956,7 @@ FILTER STRING PROC_EXEC STRING {
 	dict_set(conf->sc_filters_dict, $2, filter_config);
 } proc_params {
 	if (!processor->tag)
-		processor->tag = processor_maketag(processor->command);
+		processor->tag = processor_maketag(filter_config->proc);
 	dict_set(conf->sc_filter_processes_dict, filter_config->proc, processor);
 	processor = NULL;
 	filter_config = NULL;
@@ -3685,22 +3685,16 @@ config_lo_mask_source(struct listen_opts *lo) {
 
 /* Best effort. If it's ugly: use the tag parameter */
 static const char *
-processor_maketag(const char *cmd)
+processor_maketag(const char *name)
 {
-	char path[PATH_MAX];
-	int i, j;
-	char *tag;
+	char tag[TAG_MAX + 1];
+	size_t i, j;
 
-	strlcpy(path, cmd, sizeof(path));
-	for (i = 0; path[i] != '\0' && !isspace(path[i]); i++)
-		continue;
-	path[i] = '\0';
-	tag = basename(path);
-	for (i = j = 0; tag[j] != '\0'; j++) {
-		if (isalpha(tag[j]))
-			tag[i++] = tag[j];
+	for (i = j = 0; name[i] != '\0' && j < sizeof(tag) - 1; i++) {
+		if (isalnum(name[i]))
+			tag[j++] = name[i];
 	}
-	tag[i] = '\0';
+	tag[j] = '\0';
 
-	return xstrndup(tag, TAG_MAX);
+	return xstrdup(tag);
 }
commit - a9b792a8dce6145cbe526f847ad0f84cf9afd558
blob - 1cdaf067c5585ca69bb19baf72014d29adfe6747
file + usr.sbin/smtpd/smtpd.conf.5
--- usr.sbin/smtpd/smtpd.conf.5
+++ usr.sbin/smtpd/smtpd.conf.5
@@ -915,8 +915,7 @@ with which all log messages of this processor are writ
 .Ar tag
 is limited to 32 letters.
 The default is a best effort representation of the
-.Ar command
-name.
+.Ar proc-name .
 .El
 .It Ic queue Cm compression
 Store queue files in a compressed format.
commit - a9b792a8dce6145cbe526f847ad0f84cf9afd558
blob - 3574db4c03d611801672016b1d0d4314746802cf
file + usr.sbin/smtpd/smtpd.h
--- usr.sbin/smtpd/smtpd.h
+++ usr.sbin/smtpd/smtpd.h
@@ -1712,7 +1712,6 @@ int xasprintf(char **, const char *, ...)
 void *xmalloc(size_t);
 void *xcalloc(size_t, size_t);
 char *xstrdup(const char *);
-char *xstrndup(const char *, size_t);
 void *xmemdup(const void *, size_t);
 char *strip(char *);
 int io_xprint(struct io *, const char *);
commit - a9b792a8dce6145cbe526f847ad0f84cf9afd558
blob - ee4520d863e2434f5d047ec24be1716f05cf20c9
file + usr.sbin/smtpd/util.c
--- usr.sbin/smtpd/util.c
+++ usr.sbin/smtpd/util.c
@@ -76,17 +76,6 @@ xstrdup(const char *str)
 	return (r);
 }
 
-char *
-xstrndup(const char *str, size_t maxlen)
-{
-	char	*r;
-
-	if ((r = strndup(str, maxlen)) == NULL)
-		fatal("strdup");
-
-	return (r);
-}
-
 void *
 xmemdup(const void *ptr, size_t size)
 {