3 files changed, 42 insertions, 3 deletions
diff --git a/src/shared/conf-parser.c b/src/shared/conf-parser.c
index 1141f9964f..83be79a4f5 100644
--- a/src/shared/conf-parser.c
+++ b/src/shared/conf-parser.c
@@ -37,6 +37,7 @@
 #include "path-util.h"
 #include "process-util.h"
 #include "signal-util.h"
+#include "socket-util.h"
 #include "string-util.h"
 #include "strv.h"
 #include "syslog-util.h"
@@ -873,3 +874,40 @@ int config_parse_personality(
         *personality = p;
         return 0;
 }
+
+int config_parse_ifname(
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        char **s = data;
+        int r;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        if (isempty(rvalue)) {
+                *s = mfree(*s);
+                return 0;
+        }
+
+        if (!ifname_valid(rvalue)) {
+                log_syntax(unit, LOG_ERR, filename, line, 0, "Interface name is not valid or too long, ignoring assignment: %s", rvalue);
+                return 0;
+        }
+
+        r = free_and_strdup(s, rvalue);
+        if (r < 0)
+                return log_oom();
+
+        return 0;
+}
diff --git a/src/shared/conf-parser.h b/src/shared/conf-parser.h
index 73fb132413..f6964e3fd4 100644
--- a/src/shared/conf-parser.h
+++ b/src/shared/conf-parser.h
@@ -125,6 +125,7 @@ int config_parse_log_facility(const char *unit, const char *filename, unsigned l
 int config_parse_log_level(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_signal(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_personality(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+int config_parse_ifname(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 
 #define DEFINE_CONFIG_PARSE_ENUM(function,name,type,msg)                \
         int function(const char *unit,                                  \
diff --git a/src/shared/firewall-util.c b/src/shared/firewall-util.c
index ade2de7727..97865eac4a 100644
--- a/src/shared/firewall-util.c
+++ b/src/shared/firewall-util.c
@@ -44,6 +44,7 @@
 #include "firewall-util.h"
 #include "in-addr-util.h"
 #include "macro.h"
+#include "socket-util.h"
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(struct xtc_handle*, iptc_free);
 
@@ -59,10 +60,9 @@ static int entry_fill_basics(
 
         assert(entry);
 
-        if (out_interface && strlen(out_interface) >= IFNAMSIZ)
+        if (out_interface && !ifname_valid(out_interface))
                 return -EINVAL;
-
-        if (in_interface && strlen(in_interface) >= IFNAMSIZ)
+        if (in_interface && !ifname_valid(in_interface))
                 return -EINVAL;
 
         entry->ip.proto = protocol;