From 2d26304663e00cb58b5519cb1b7dc05cca1fbbe5 Mon Sep 17 00:00:00 2001
From: James Prestwood <prestwoj@gmail.com>
Date: Tue, 5 Dec 2023 07:46:38 -0800
Subject: [PATCH] scan: parse password identifier/exclusive bits

These bits are used to communicate to the station that SAE password
identifiers are used or required.
---
 src/scan.c | 20 +++++++++++++++++---
 src/scan.h |  2 ++
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/scan.c b/src/scan.c
index 5aa92a90..f48ffdef 100644
--- a/src/scan.c
+++ b/src/scan.c
@@ -1404,10 +1404,24 @@ static bool scan_parse_bss_information_elements(struct scan_bss *bss,
 			 * Currently only Proxy ARP bit (12) is checked, and if
 			 * not found, this is not a fatal error.
 			 */
-			if (iter.len < 2)
-				break;
+			if (iter.len >= 2)
+				bss->proxy_arp = test_bit(iter.data, 12);
+
+			/*
+			 * 802.11-2020 Table 9-153
+			 *
+			 * The spec merely mentions the "exclusive" bit and
+			 * doesn't enforce a requirement to check it anywhere.
+			 * But if set it would indicate the AP will only accept
+			 * auths when a password ID is used so store this in
+			 * order to fail early if no ID is set.
+			 */
+			if (iter.len >= 11) {
+				bss->sae_pw_id_used = test_bit(iter.data, 81);
+				bss->sae_pw_id_exclusive =
+							test_bit(iter.data, 82);
+			}
 
-			bss->proxy_arp = test_bit(iter.data, 12);
 		}
 	}
 
diff --git a/src/scan.h b/src/scan.h
index 0db7752d..65caf41c 100644
--- a/src/scan.h
+++ b/src/scan.h
@@ -88,6 +88,8 @@ struct scan_bss {
 	uint8_t cost_level : 3;
 	uint8_t cost_flags : 4;
 	bool dpp_configurator : 1;
+	bool sae_pw_id_used : 1;
+	bool sae_pw_id_exclusive : 1;
 };
 
 struct scan_parameters {