FILS: Move AssocResp construction to a helper function

This can be reused from driver-based AP SME callback.

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

diff --git a/src/ap/wpa_auth.c b/src/ap/wpa_auth.c
index c92aca06355b4fe321c30c6603d820e43b0aa674..fcd4736c9b6f50350dc79c439a6916a5c359857b 100644 (file)
--- a/src/ap/wpa_auth.c
+++ b/src/ap/wpa_auth.c
@@ -40,6 +40,8 @@ static int wpa_verify_key_mic(int akmp, struct wpa_ptk *PTK, u8 *data,
 #ifdef CONFIG_FILS
 static int wpa_aead_decrypt(struct wpa_state_machine *sm, struct wpa_ptk *ptk,
                            u8 *buf, size_t buf_len, u16 *_key_data_len);
+static struct wpabuf * fils_prepare_plainbuf(struct wpa_state_machine *sm,
+                                            const struct wpabuf *hlp);
 #endif /* CONFIG_FILS */
 static void wpa_sm_call_step(void *eloop_ctx, void *timeout_ctx);
 static void wpa_group_sm_step(struct wpa_authenticator *wpa_auth,
@@ -2349,11 +2351,6 @@ int fils_encrypt_assoc(struct wpa_state_machine *sm, u8 *buf,
        u8 *pos = buf + current_len;
        struct ieee80211_mgmt *mgmt;
        struct wpabuf *plain;
-       u8 *len, *tmp, *tmp2;
-       u8 hdr[2];
-       u8 *gtk, dummy_gtk[32];
-       size_t gtk_len;
-       struct wpa_group *gsm;
        const u8 *aad[5];
        size_t aad_len[5];
 
@@ -2389,10 +2386,54 @@ int fils_encrypt_assoc(struct wpa_state_machine *sm, u8 *buf,
        aad_len[4] = pos - aad[4];
 
        /* The following elements will be encrypted with AES-SIV */
+       plain = fils_prepare_plainbuf(sm, hlp);
+       if (!plain) {
+               wpa_printf(MSG_DEBUG, "FILS: Plain buffer prep failed");
+               return -1;
+       }
+
+       if (pos + wpabuf_len(plain) + AES_BLOCK_SIZE > end) {
+               wpa_printf(MSG_DEBUG,
+                          "FILS: Not enough room for FILS elements");
+               wpabuf_free(plain);
+               return -1;
+       }
+
+       wpa_hexdump_buf_key(MSG_DEBUG, "FILS: Association Response plaintext",
+                           plain);
+
+       if (aes_siv_encrypt(sm->PTK.kek, sm->PTK.kek_len,
+                           wpabuf_head(plain), wpabuf_len(plain),
+                           5, aad, aad_len, pos) < 0) {
+               wpabuf_free(plain);
+               return -1;
+       }
+
+       wpa_hexdump(MSG_DEBUG,
+                   "FILS: Encrypted Association Response elements",
+                   pos, AES_BLOCK_SIZE + wpabuf_len(plain));
+       current_len += wpabuf_len(plain) + AES_BLOCK_SIZE;
+       wpabuf_free(plain);
+
+       sm->fils_completed = 1;
+
+       return current_len;
+}
+
+
+static struct wpabuf * fils_prepare_plainbuf(struct wpa_state_machine *sm,
+                                            const struct wpabuf *hlp)
+{
+       struct wpabuf *plain;
+       u8 *len, *tmp, *tmp2;
+       u8 hdr[2];
+       u8 *gtk, dummy_gtk[32];
+       size_t gtk_len;
+       struct wpa_group *gsm;
 
        plain = wpabuf_alloc(1000);
        if (!plain)
-               return -1;
+               return NULL;
 
        /* TODO: FILS Public Key */
 
@@ -2426,7 +2467,7 @@ int fils_encrypt_assoc(struct wpa_state_machine *sm, u8 *buf,
                 */
                if (random_get_bytes(dummy_gtk, gtk_len) < 0) {
                        wpabuf_free(plain);
-                       return -1;
+                       return NULL;
                }
                gtk = dummy_gtk;
        }
@@ -2443,33 +2484,7 @@ int fils_encrypt_assoc(struct wpa_state_machine *sm, u8 *buf,
        wpabuf_put(plain, tmp2 - tmp);
 
        *len = (u8 *) wpabuf_put(plain, 0) - len - 1;
-
-       if (pos + wpabuf_len(plain) + AES_BLOCK_SIZE > end) {
-               wpa_printf(MSG_DEBUG,
-                          "FILS: Not enough room for FILS elements");
-               wpabuf_free(plain);
-               return -1;
-       }
-
-       wpa_hexdump_buf_key(MSG_DEBUG, "FILS: Association Response plaintext",
-                           plain);
-
-       if (aes_siv_encrypt(sm->PTK.kek, sm->PTK.kek_len,
-                           wpabuf_head(plain), wpabuf_len(plain),
-                           5, aad, aad_len, pos) < 0) {
-               wpabuf_free(plain);
-               return -1;
-       }
-
-       wpa_hexdump(MSG_DEBUG,
-                   "FILS: Encrypted Association Response elements",
-                   pos, AES_BLOCK_SIZE + wpabuf_len(plain));
-       current_len += wpabuf_len(plain) + AES_BLOCK_SIZE;
-       wpabuf_free(plain);
-
-       sm->fils_completed = 1;
-
-       return current_len;
+       return plain;
 }