mesh: Document Mesh Peering Management element structure in more detail

Provide details on the pointers to the subfields and rename "pmk" to
"chosen_pmk" and use SAE_PMKID_LEN macro with it to make the code more
readable.

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

diff --git a/wpa_supplicant/mesh_mpm.c b/wpa_supplicant/mesh_mpm.c
index 3259151a58f82a5c3db1565b9a665d21dbb8495f..4caa55ce5871d57d274ce45d0b7d141006f7e49e 100644 (file)
--- a/wpa_supplicant/mesh_mpm.c
+++ b/wpa_supplicant/mesh_mpm.c
@@ -20,11 +20,11 @@
 #include "mesh_rsn.h"
 
 struct mesh_peer_mgmt_ie {
-       const u8 *proto_id;
-       const u8 *llid;
-       const u8 *plid;
-       const u8 *reason;
-       const u8 *pmk;
+       const u8 *proto_id; /* Mesh Peering Protocol Identifier (2 octets) */
+       const u8 *llid; /* Local Link ID (2 octets) */
+       const u8 *plid; /* Peer Link ID (conditional, 2 octets) */
+       const u8 *reason; /* Reason Code (conditional, 2 octets) */
+       const u8 *chosen_pmk; /* Chosen PMK (optional, 16 octets) */
 };
 
 static void plink_timer(void *eloop_ctx, void *user_data);
@@ -72,10 +72,10 @@ static int mesh_mpm_parse_peer_mgmt(struct wpa_supplicant *wpa_s,
 {
        os_memset(mpm_ie, 0, sizeof(*mpm_ie));
 
-       /* remove optional PMK at end */
-       if (len >= 16) {
-               mpm_ie->pmk = ie + len - 16;
-               len -= 16;
+       /* Remove optional Chosen PMK field at end */
+       if (len >= SAE_PMKID_LEN) {
+               mpm_ie->chosen_pmk = ie + len - SAE_PMKID_LEN;
+               len -= SAE_PMKID_LEN;
        }
 
        if ((action_field == PLINK_OPEN && len != 4) ||
@@ -101,8 +101,8 @@ static int mesh_mpm_parse_peer_mgmt(struct wpa_supplicant *wpa_s,
                len -= 2;
        }
 
-       /* plid, present for confirm, and possibly close */
-       if (len)
+       /* Peer Link ID, present for confirm, and possibly close */
+       if (len >= 2)
                mpm_ie->plid = ie;
 
        return 0;
@@ -1014,7 +1014,7 @@ void mesh_mpm_action_rx(struct wpa_supplicant *wpa_s,
        if ((mconf->security & MESH_CONF_SEC_AMPE) &&
            mesh_rsn_process_ampe(wpa_s, sta, &elems,
                                  &mgmt->u.action.category,
-                                 peer_mgmt_ie.pmk,
+                                 peer_mgmt_ie.chosen_pmk,
                                  ies, ie_len)) {
                wpa_printf(MSG_DEBUG, "MPM: RSN process rejected frame");
                return;