Work around AP misbehavior on EAPOL-Key descriptor version

It looks like some APs are incorrectly selecting descriptor version 3
(AES-128-CMAC) for EAPOL-Key frames when version 2 (HMAC-SHA1) was
expected to be used. This is likely triggered by an attempt to negotiate
PMF with SHA1-based AKM.

Since AES-128-CMAC is considered stronger than HMAC-SHA1, allow the
incorrect, but stronger, option to be used in these cases to avoid
interoperability issues with deployed APs.

This issue shows up with "WPA: CCMP is used, but EAPOL-Key descriptor
version (3) is not 2" in debug log. With the new workaround, this issue
is ignored and "WPA: Interoperability workaround: allow incorrect
(should have been HMAC-SHA1), but stronger (is AES-128-CMAC), descriptor
version to be used" is written to the log.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

Diffstat

-rw-r--r-- src/rsn_supp/wpa.c

1 files changed, 3 insertions, 0 deletions

diff --git a/src/rsn_supp/wpa.c b/src/rsn_supp/wpa.c
index d95c1bd..f8825d2 100644
--- a/src/rsn_supp/wpa.c
+++ b/src/rsn_supp/wpa.c
@@ -1756,6 +1756,9 @@ int wpa_sm_rx_eapol(struct wpa_sm *sm, const u8 *src_addr,
 			wpa_msg(sm->ctx->msg_ctx, MSG_INFO,
 				"WPA: Backwards compatibility: allow invalid "
 				"version for non-CCMP group keys");
+		} else if (ver == WPA_KEY_INFO_TYPE_AES_128_CMAC) {
+			wpa_msg(sm->ctx->msg_ctx, MSG_INFO,
+				"WPA: Interoperability workaround: allow incorrect (should have been HMAC-SHA1), but stronger (is AES-128-CMAC), descriptor version to be used");
 		} else
 			goto out;
 	} else if (sm->pairwise_cipher == WPA_CIPHER_GCMP &&
add patch to fix InputMethodManagerService crash while switching user