This might be useful for debugging.

Applies log on either match/pass rules and can be changed via relayctl reload.
Attached to listen on directive.

G

Index: parse.y
===================================================================
RCS file: /cvs/src/usr.sbin/relayd/parse.y,v
retrieving revision 1.255
diff -u -p -u -p -r1.255 parse.y
--- parse.y	29 Oct 2023 11:27:11 -0000	1.255
+++ parse.y	22 May 2024 15:12:09 -0000
@@ -179,14 +179,14 @@ typedef struct {
 %token	TIMEOUT TLS TO ROUTER RTLABEL TRANSPARENT URL WITH TTL RTABLE
 %token	MATCH PARAMS RANDOM LEASTSTATES SRCHASH KEY CERTIFICATE PASSWORD ECDHE
 %token	EDH TICKETS CONNECTION CONNECTIONS CONTEXT ERRORS STATE CHANGES CHECKS
-%token	WEBSOCKETS
+%token	WEBSOCKETS PFLOG
 %token	<v.string>	STRING
 %token  <v.number>	NUMBER
 %type	<v.string>	context hostname interface table value path
 %type	<v.number>	http_type loglevel quick
 %type	<v.number>	dstmode flag forwardmode retry
 %type	<v.number>	opttls opttlsclient
-%type	<v.number>	redirect_proto relay_proto match
+%type	<v.number>	redirect_proto relay_proto match pflog
 %type	<v.number>	action ruleaf key_option
 %type	<v.port>	port
 %type	<v.host>	host
@@ -605,7 +605,7 @@ rdroptsl	: forwardmode TO tablespec inte
 			$3->conf.rdrid = rdr->conf.id;
 			$3->conf.flags |= F_USED;
 		}
-		| LISTEN ON STRING redirect_proto port interface {
+		| LISTEN ON STRING redirect_proto port interface pflog {
 			if (host($3, &rdr->virts,
 			    SRV_MAX_VIRTS, &$5, $6, $4) <= 0) {
 				yyerror("invalid virtual ip: %s", $3);
@@ -618,6 +618,8 @@ rdroptsl	: forwardmode TO tablespec inte
 			if (rdr->conf.port == 0)
 				rdr->conf.port = $5.val[0];
 			tableport = rdr->conf.port;
+			if ($7)
+				rdr->conf.flags |= F_PFLOG;
 		}
 		| DISABLE		{ rdr->conf.flags |= F_DISABLE; }
 		| STICKYADDR		{ rdr->conf.flags |= F_STICKY; }
@@ -651,6 +653,10 @@ match		: /* empty */		{ $$ = 0; }
 		| MATCH			{ $$ = 1; }
 		;
 
+pflog		: /* empty */		{ $$ = 0; }
+		| PFLOG			{ $$ = 1; }
+		;
+
 forwardmode	: FORWARD		{ $$ = FWD_NORMAL; }
 		| ROUTE			{ $$ = FWD_ROUTE; }
 		| TRANSPARENT FORWARD	{ $$ = FWD_TRANS; }
@@ -2454,6 +2460,7 @@ lookup(char *s)
 		{ "pass",		PASS },
 		{ "password",		PASSWORD },
 		{ "path",		PATH },
+		{ "pflog",		PFLOG },
 		{ "pftag",		PFTAG },
 		{ "port",		PORT },
 		{ "prefork",		PREFORK },
Index: pfe_filter.c
===================================================================
RCS file: /cvs/src/usr.sbin/relayd/pfe_filter.c,v
retrieving revision 1.65
diff -u -p -u -p -r1.65 pfe_filter.c
--- pfe_filter.c	14 Sep 2023 09:54:31 -0000	1.65
+++ pfe_filter.c	22 May 2024 15:12:09 -0000
@@ -377,6 +377,11 @@ sync_ruleset(struct relayd *env, struct 
 		rio.rule.direction = PF_IN;
 		rio.rule.keep_state = PF_STATE_NORMAL;
 
+		if (rdr->conf.flags & F_PFLOG)
+			rio.rule.log = 1;
+		else
+			rio.rule.log = 0; /* allow change via reload */
+
 		switch (t->conf.fwdmode) {
 		case FWD_NORMAL:
 			/* traditional redirection */
Index: relayd.conf.5
===================================================================
RCS file: /cvs/src/usr.sbin/relayd/relayd.conf.5,v
retrieving revision 1.207
diff -u -p -u -p -r1.207 relayd.conf.5
--- relayd.conf.5	29 Oct 2023 11:27:11 -0000	1.207
+++ relayd.conf.5	22 May 2024 15:12:09 -0000
@@ -517,6 +517,7 @@ At least one entry for the main table is
 .Op ip-proto
 .Ic port Ar port
 .Op Ic interface Ar name
+.Op Ic pflog
 .Xc
 Specify an
 .Ar address
@@ -540,6 +541,12 @@ or
 it defaults to
 .Cm tcp .
 The rule can be optionally restricted to a given interface name.
+The optional
+.Ic pflog
+keyword will add 
+.Cm log
+to the rule. The logged packets are sent to
+.Xr pflog 4 .
 .It Xo
 .Op Ic match
 .Ic pftag Ar name
Index: relayd.h
===================================================================
RCS file: /cvs/src/usr.sbin/relayd/relayd.h,v
retrieving revision 1.272
diff -u -p -u -p -r1.272 relayd.h
--- relayd.h	18 May 2024 06:34:46 -0000	1.272
+++ relayd.h	22 May 2024 15:12:09 -0000
@@ -402,6 +402,7 @@ union hashkey {
 #define F_TLSINSPECT		0x04000000
 #define F_HASHKEY		0x08000000
 #define F_AGENTX_TRAPONLY	0x10000000
+#define F_PFLOG	0x20000000
 
 #define F_BITS								\
 	"\10\01DISABLE\02BACKUP\03USED\04DOWN\05ADD\06DEL\07CHANGED"	\