[PATCH 26/97] NAN: Process IGTK KDE from NDP setup messages
Andrei Otcheretianski
andrei.otcheretianski at intel.com
Tue Apr 28 13:05:27 PDT 2026
From: Avraham Stern <avraham.stern at intel.com>
When an IGTK KDE is included in the key data field of NDP setup
M3 and M4 messages, parse the KDE and install the IGTK for Rx
from this peer.
Signed-off-by: Avraham Stern <avraham.stern at intel.com>
---
src/nan/nan_i.h | 3 ++
src/nan/nan_sec.c | 114 ++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 112 insertions(+), 5 deletions(-)
diff --git a/src/nan/nan_i.h b/src/nan/nan_i.h
index e3babcd171..a21e9d3f8e 100644
--- a/src/nan/nan_i.h
+++ b/src/nan/nan_i.h
@@ -528,6 +528,7 @@ struct nan_pairing_peer_data {
* @ndl: NDL data associated with this peer
* @bootstrap: Bootstrap information of the peer
* @pairing: Pairing data associated with this peer
+ * @igtk_id: IGTK key ID used with this peer. Zero if IGTK is not used.
*/
struct nan_peer {
struct dl_list list;
@@ -545,6 +546,8 @@ struct nan_peer {
struct nan_bootstrap bootstrap;
struct nan_pairing_peer_data pairing;
+
+ u8 igtk_id;
};
/**
diff --git a/src/nan/nan_sec.c b/src/nan/nan_sec.c
index 115fb137a2..7220fc7fa3 100644
--- a/src/nan/nan_sec.c
+++ b/src/nan/nan_sec.c
@@ -422,6 +422,94 @@ static int nan_sec_rx_m4(struct nan_data *nan, struct nan_peer *peer,
}
+static int nan_sec_rx_key_data(struct nan_data *nan,
+ struct nan_peer *peer, u8 peer_capab,
+ const u8 *enc_key_data, size_t key_data_len)
+{
+ struct wpabuf *key_data = NULL;
+ struct wpa_eapol_ie_parse ie;
+ struct nan_ndp_sec *ndp_sec = &peer->ndp_setup.sec;
+ int ret = -1;
+ int cipher;
+ unsigned int key_len;
+ enum wpa_alg alg;
+
+ if (((peer_capab & NAN_CS_INFO_CAPA_GTK_SUPP_MASK) >>
+ NAN_CS_INFO_CAPA_GTK_SUPP_POS) == NAN_CS_INFO_CAPA_GTK_SUPP_NONE) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: SEC: Peer does not support IGTK/BIGTK, ignore key data");
+ return 0;
+ }
+
+ if (peer_capab & NAN_CS_INFO_CAPA_IGTK_USE_NCS_BIP_GMAC_256) {
+ cipher = WPA_CIPHER_BIP_GMAC_256;
+ alg = WPA_ALG_BIP_GMAC_256;
+ } else {
+ cipher = WPA_CIPHER_AES_128_CMAC;
+ alg = WPA_ALG_BIP_CMAC_128;
+ }
+
+ key_len = wpa_cipher_key_len(cipher);
+
+ key_data = nan_crypto_decrypt_key_data(ndp_sec->ptk.kek,
+ ndp_sec->ptk.kek_len,
+ enc_key_data, key_data_len);
+ if (!key_data) {
+ wpa_printf(MSG_DEBUG, "NAN: SEC: Failed to decrypt key data");
+ return -1;
+ }
+
+ if (wpa_parse_kde_ies(wpabuf_head(key_data), wpabuf_len(key_data),
+ &ie) < 0) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: SEC: Failed to parse decrypted key data");
+ goto fail;
+ }
+
+ if (ie.igtk && ie.igtk_len) {
+ struct wpa_igtk_kde *igtk_kde = (struct wpa_igtk_kde *)ie.igtk;
+ u16 key_idx;
+
+ if (ie.igtk_len != WPA_IGTK_KDE_PREFIX_LEN + key_len) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: SEC: Invalid IGTK KDE length: %zu (expected %u)",
+ ie.igtk_len,
+ WPA_IGTK_KDE_PREFIX_LEN + key_len);
+ goto fail;
+ }
+
+ /* Key ID must be 4 or 5, see Wi-Fi Aware Specification v4.0,
+ * section 7.1.3.3
+ */
+ key_idx = WPA_GET_LE16(igtk_kde->keyid);
+ if (key_idx < 4 || key_idx > 5) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: SEC: Invalid IGTK key index: %u",
+ key_idx);
+ goto fail;
+ }
+
+ if (nan->cfg->set_group_key(nan->cfg->cb_ctx, alg,
+ peer->nmi_addr, key_idx,
+ igtk_kde->pn, igtk_kde->igtk,
+ key_len, KEY_FLAG_GROUP_RX) < 0) {
+ wpa_printf(MSG_DEBUG,
+ "NAN: SEC: Failed to install IGTK");
+ goto fail;
+ }
+
+ peer->igtk_id = key_idx;
+ wpa_hexdump_key(MSG_DEBUG, "NAN: SEC: Received IGTK",
+ igtk_kde->igtk, key_len);
+ }
+
+ ret = 0;
+fail:
+ wpabuf_clear_free(key_data);
+ return ret;
+}
+
+
/**
* nan_sec_rx - Handle security context for Rx frames
* @nan: NAN module context from nan_init()
@@ -437,7 +525,7 @@ int nan_sec_rx(struct nan_data *nan, struct nan_peer *peer,
struct wpa_eapol_key *key;
struct nan_shared_key *shared_key_desc;
size_t shared_key_desc_len;
- u16 info, desc;
+ u16 info, desc, key_data_len;
size_t total_len;
u8 instance_id, cipher, capab, gtk_csid;
u8 *pos;
@@ -498,8 +586,9 @@ int nan_sec_rx(struct nan_data *nan, struct nan_peer *peer,
return -1;
}
- total_len += NAN_KEY_MIC_LEN +
- WPA_GET_BE16(pos + NAN_KEY_MIC_LEN);
+ key_data_len = WPA_GET_BE16(pos + NAN_KEY_MIC_LEN);
+ total_len += NAN_KEY_MIC_LEN + key_data_len;
+ pos += NAN_KEY_MIC_LEN + 2;
if (total_len >
(shared_key_desc_len - sizeof(struct nan_shared_key))) {
@@ -516,8 +605,9 @@ int nan_sec_rx(struct nan_data *nan, struct nan_peer *peer,
return -1;
}
- total_len += NAN_KEY_MIC_24_LEN +
- WPA_GET_BE16(pos + NAN_KEY_MIC_24_LEN);
+ key_data_len = WPA_GET_BE16(pos + NAN_KEY_MIC_24_LEN);
+ total_len += NAN_KEY_MIC_24_LEN + key_data_len;
+ pos += NAN_KEY_MIC_24_LEN + 2;
if (total_len >
(shared_key_desc_len - sizeof(struct nan_shared_key))) {
@@ -601,12 +691,26 @@ int nan_sec_rx(struct nan_data *nan, struct nan_peer *peer,
!(info & WPA_KEY_INFO_SECURE))
return -1;
ret = nan_sec_rx_m3(nan, peer, msg, key);
+
+ /* Ignore unencrypted key data */
+ if (!ret && key_data_len > 0 &&
+ (info & WPA_KEY_INFO_ENCR_KEY_DATA))
+ ret = nan_sec_rx_key_data(nan, peer,
+ ndp_sec->i_capab, pos,
+ key_data_len);
break;
case NAN_SUBTYPE_DATA_PATH_KEY_INSTALL:
if (!(info & WPA_KEY_INFO_MIC) ||
!(info & WPA_KEY_INFO_SECURE))
return -1;
ret = nan_sec_rx_m4(nan, peer, msg, key);
+
+ /* Ignore unencrypted key data */
+ if (!ret && key_data_len > 0 &&
+ (info & WPA_KEY_INFO_ENCR_KEY_DATA))
+ ret = nan_sec_rx_key_data(nan, peer,
+ ndp_sec->r_capab, pos,
+ key_data_len);
break;
default:
wpa_printf(MSG_DEBUG, "NAN: SEC: Invalid frame OUI subtype");
--
2.53.0
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