git: e5536b061033 - stable/14 - pfctl: relax interface name requirement

The branch stable/14 has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=e5536b061033bdc56cee7c1d42ab4fc17f5b8051

commit e5536b061033bdc56cee7c1d42ab4fc17f5b8051
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2026-05-07 09:58:17 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2026-05-14 19:04:19 +0000

    pfctl: relax interface name requirement
    
    The FreeBSD network stack, for better or worse, does not impose any
    requirements on interface names. As such it's valid for an interface
    name to start with a number (or indeed, be something like '⭐').
    
    Allow this in pfctl, and add a test case for the specific case of
    interface names starting with a number.
    
    Note that we don't support UTF-8 names fully, so those may still fail.
    
    PR:             295064
    MFC after:      1 week
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
    
    (cherry picked from commit 4e7c1ff95a5187faee524055f22c4cf4134d1147)
---
 sbin/pfctl/parse.y            |  2 +-
 tests/sys/netpfil/pf/names.sh | 40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/sbin/pfctl/parse.y b/sbin/pfctl/parse.y
index 58245ca642e0..df17486a5d45 100644
--- a/sbin/pfctl/parse.y
+++ b/sbin/pfctl/parse.y
@@ -3728,7 +3728,7 @@ dynaddr		: '(' STRING ')'		{
 			char	*p, *op;
 
 			op = $2;
-			if (!isalpha(op[0])) {
+			if (op[0] == '\0') {
 				yyerror("invalid interface name '%s'", op);
 				free(op);
 				YYERROR;
diff --git a/tests/sys/netpfil/pf/names.sh b/tests/sys/netpfil/pf/names.sh
index e47b0917cfec..c6f2a06c15f9 100644
--- a/tests/sys/netpfil/pf/names.sh
+++ b/tests/sys/netpfil/pf/names.sh
@@ -95,8 +95,48 @@ group_cleanup()
 	pft_cleanup
 }
 
+atf_test_case "start_number" "cleanup"
+start_number_head()
+{
+	atf_set descr 'Test interface names starting with a number'
+	atf_set require.user root
+}
+
+start_number_body()
+{
+	pft_init
+
+	epair=$(vnet_mkepair)
+	ifconfig ${epair}a 192.0.2.1/24 up
+
+	vnet_mkjail alcatraz ${epair}b
+	jexec alcatraz ifconfig ${epair}b 192.0.2.2/24 up
+	jexec alcatraz ifconfig ${epair}b name 4ever
+	jexec alcatraz pfctl -e
+
+	jexec alcatraz ifconfig
+
+	pft_set_rules alcatraz \
+	    "block" \
+	    "pass in from any to (4ever)"
+
+	atf_check -o ignore ping -c 3 192.0.2.2
+
+	# Negative test, if the interface doesn't exist we don't pass packets
+	pft_set_rules alcatraz \
+	    "block" \
+	    "pass in from any to (5ever)"
+	atf_check -s exit:2 -o ignore ping -c 1 -t 1 192.0.2.2
+}
+
+start_number_cleanup()
+{
+	pft_cleanup
+}
+
 atf_init_test_cases()
 {
 	atf_add_test_case "names"
 	atf_add_test_case "group"
+	atf_add_test_case "start_number"
 }