From c93966d5a18d6222d26c276f4b4cfb7626b6ddc6 Mon Sep 17 00:00:00 2001
From: Denis Kenzior <denkenz@gmail.com>
Date: Fri, 3 Sep 2021 16:26:46 -0500
Subject: [PATCH] ie: Add parse utility for network cost vendor IE

---
 src/ie.c | 20 ++++++++++++++++++++
 src/ie.h |  3 +++
 2 files changed, 23 insertions(+)

diff --git a/src/ie.c b/src/ie.c
index 0aa86af6..1ce1d8a5 100644
--- a/src/ie.c
+++ b/src/ie.c
@@ -2472,3 +2472,23 @@ void ie_build_fils_ip_addr_response(
 done:
 	*len = to - (len + 1);
 }
+
+/*
+ * Parse Network Cost IE according to:
+ * https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-nct/88f0cdf4-cdf2-4455-b849-4abf1e5c11ac
+ */
+int ie_parse_network_cost(const void *data, size_t len,
+				uint16_t *level, uint16_t *flags)
+{
+	const uint8_t *ie = data;
+
+	if (len < 10 || ie[0] != IE_TYPE_VENDOR_SPECIFIC || ie[1] != 8)
+		return -ENOMSG;
+
+	if (memcmp(ie + 2, microsoft_oui, 3) || ie[5] != 0x11)
+		return -ENOMSG;
+
+	*level = l_get_le16(ie + 6);
+	*flags = l_get_le16(ie + 8);
+	return 0;
+}
diff --git a/src/ie.h b/src/ie.h
index 8d4ab3c1..a2fdc2e3 100644
--- a/src/ie.h
+++ b/src/ie.h
@@ -626,3 +626,6 @@ int ie_parse_fils_ip_addr_response(struct ie_tlv_iter *iter,
 void ie_build_fils_ip_addr_response(
 			const struct ie_fils_ip_addr_response_info *info,
 			uint8_t *to);
+
+int ie_parse_network_cost(const void *data, size_t len,
+				uint16_t *flags, uint16_t *level);