1 files changed, 64 insertions, 0 deletions
diff --git a/lib/inet_proto.c b/lib/inet_proto.c
new file mode 100644
index 0000000..71cd3b1
--- /dev/null
+++ b/lib/inet_proto.c
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * inet_proto.c
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <string.h>
+
+#include "rt_names.h"
+#include "utils.h"
+
+const char *inet_proto_n2a(int proto, char *buf, int len)
+{
+	static char *ncache;
+	static int icache = -1;
+	struct protoent *pe;
+
+	if (proto == icache)
+		return ncache;
+
+	pe = getprotobynumber(proto);
+	if (pe && !numeric) {
+		if (icache != -1)
+			free(ncache);
+		icache = proto;
+		ncache = strdup(pe->p_name);
+		strlcpy(buf, pe->p_name, len);
+		return buf;
+	}
+	snprintf(buf, len, "ipproto-%d", proto);
+	return buf;
+}
+
+int inet_proto_a2n(const char *buf)
+{
+	static char *ncache;
+	static int icache = -1;
+	struct protoent *pe;
+	__u8 ret;
+
+	if (icache != -1 && strcmp(ncache, buf) == 0)
+		return icache;
+
+	if (!get_u8(&ret, buf, 10))
+		return ret;
+
+	pe = getprotobyname(buf);
+	if (pe) {
+		if (icache != -1)
+			free(ncache);
+		icache = pe->p_proto;
+		ncache = strdup(pe->p_name);
+		return pe->p_proto;
+	}
+	return -1;
+}