DGNum/hostapd
6
0
Fork 0
Code Issues Pull requests 1 Projects Releases Packages Wiki Activity Actions

WPA: Explicitly clear the buffer used for decrypting Key Data

Browse source 
When AES-WRAP was used to protect the EAPOL-Key Key Data field, this was
decrypted using a temporary heap buffer with aes_unwrap(). That buffer
was not explicitly cleared, so it was possible for the group keys to
remain in memory unnecessarily until the allocated area was reused.
Clean this up by clearing the temporary allocation explicitly before
freeing it.

Signed-off-by: Jouni Malinen <j@w1.fi>
This commit is contained in:
Jouni Malinen 2015-12-20 10:52:30 +02:00
parent a551da6aae
commit cd5895e8c5
1 changed files with 2 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
src/rsn_supp/wpa.c
View file

@ -1670,14 +1670,14 @@ static int wpa_supplicant_decrypt_key_data(struct wpa_sm *sm,
} }
if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, *key_data_len / 8, if (aes_unwrap(sm->ptk.kek, sm->ptk.kek_len, *key_data_len / 8,
key_data, buf)) { key_data, buf)) {
os_free(buf); bin_clear_free(buf, *key_data_len);
wpa_msg(sm->ctx->msg_ctx, MSG_WARNING, wpa_msg(sm->ctx->msg_ctx, MSG_WARNING,
"WPA: AES unwrap failed - " "WPA: AES unwrap failed - "
"could not decrypt EAPOL-Key key data"); "could not decrypt EAPOL-Key key data");
return -1; return -1;
} }
os_memcpy(key_data, buf, *key_data_len); os_memcpy(key_data, buf, *key_data_len);
os_free(buf); bin_clear_free(buf, *key_data_len);
WPA_PUT_BE16(key->key_data_length, *key_data_len); WPA_PUT_BE16(key->key_data_length, *key_data_len);
} else { } else {
wpa_msg(sm->ctx->msg_ctx, MSG_WARNING, wpa_msg(sm->ctx->msg_ctx, MSG_WARNING,