ieee80211_rx_result
ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
{
u8 *data, *key = NULL, key_offset;
size_t data_len;
unsigned int hdrlen;
u8 mic[MICHAEL_MIC_LEN];
struct sk_buff *skb = rx->skb;
struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
int authenticator = 1, wpa_test = 0;
/* No way to verify the MIC if the hardware stripped it */
if (status->flag & RX_FLAG_MMIC_STRIPPED)
return RX_CONTINUE;
if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
!ieee80211_has_protected(hdr->frame_control) ||
!ieee80211_is_data_present(hdr->frame_control))
return RX_CONTINUE;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (skb->len < hdrlen + MICHAEL_MIC_LEN)
return RX_DROP_UNUSABLE;
data = skb->data + hdrlen;
data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
#if 0
authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */
#else
authenticator = 1;
#endif
key_offset = authenticator ?
NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY :
NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY;
key = &rx->key->conf.key[key_offset];
michael_mic(key, hdr, data, data_len, mic);
if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) {
if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
return RX_DROP_UNUSABLE;
mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx,
(void *) skb->data, NULL,
GFP_ATOMIC);
return RX_DROP_UNUSABLE;
}
/* remove Michael MIC from payload */
skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
/* update IV in key information to be able to detect replays */
rx->key->u.tkip.rx[rx->queue].iv32 = rx->tkip_iv32;
rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16;
return RX_CONTINUE;
}
ieee80211_tx_result
ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
{
u8 *data, *key, *mic, key_offset;
size_t data_len;
unsigned int hdrlen;
struct ieee80211_hdr *hdr;
struct sk_buff *skb = tx->skb;
int authenticator;
int wpa_test = 0;
int tail;
hdr = (struct ieee80211_hdr *)skb->data;
if (!tx->key || tx->key->conf.alg != ALG_TKIP || skb->len < 24 ||
!ieee80211_is_data_present(hdr->frame_control))
return TX_CONTINUE;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (skb->len < hdrlen)
return TX_DROP;
data = skb->data + hdrlen;
data_len = skb->len - hdrlen;
if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&
!(tx->flags & IEEE80211_TX_FRAGMENTED) &&
!(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&
!wpa_test) {
/* hwaccel - with no need for preallocated room for MMIC */
return TX_CONTINUE;
}
tail = MICHAEL_MIC_LEN;
if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
tail += TKIP_ICV_LEN;
if (WARN_ON(skb_tailroom(skb) < tail ||
skb_headroom(skb) < TKIP_IV_LEN))
return TX_DROP;
#if 0
authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
#else
authenticator = 1;
#endif
key_offset = authenticator ?
NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY :
NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;
key = &tx->key->conf.key[key_offset];
mic = skb_put(skb, MICHAEL_MIC_LEN);
michael_mic(key, hdr, data, data_len, mic);
return TX_CONTINUE;
}
ieee80211_tx_result
ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
{
u8 *data, *key, *mic, key_offset;
size_t data_len;
unsigned int hdrlen;
struct ieee80211_hdr *hdr;
struct sk_buff *skb = tx->skb;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
int authenticator;
int tail;
hdr = (struct ieee80211_hdr *)skb->data;
if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
return TX_CONTINUE;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (skb->len < hdrlen)
return TX_DROP;
data = skb->data + hdrlen;
data_len = skb->len - hdrlen;
if (info->control.hw_key &&
!(tx->flags & IEEE80211_TX_FRAGMENTED) &&
!(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
/* hwaccel - with no need for SW-generated MMIC */
return TX_CONTINUE;
}
tail = MICHAEL_MIC_LEN;
if (!info->control.hw_key)
tail += TKIP_ICV_LEN;
if (WARN_ON(skb_tailroom(skb) < tail ||
skb_headroom(skb) < TKIP_IV_LEN))
return TX_DROP;
#if 0
authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
#else
authenticator = 1;
#endif
key_offset = authenticator ?
NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY :
NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY;
key = &tx->key->conf.key[key_offset];
mic = skb_put(skb, MICHAEL_MIC_LEN);
michael_mic(key, hdr, data, data_len, mic);
return TX_CONTINUE;
}
ieee80211_tx_result
ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
{
u8 *data, *key, *mic;
size_t data_len;
unsigned int hdrlen;
struct ieee80211_hdr *hdr;
struct sk_buff *skb = tx->skb;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
int tail;
hdr = (struct ieee80211_hdr *)skb->data;
if (!tx->key || tx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
skb->len < 24 || !ieee80211_is_data_present(hdr->frame_control))
return TX_CONTINUE;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (skb->len < hdrlen)
return TX_DROP;
data = skb->data + hdrlen;
data_len = skb->len - hdrlen;
if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE)) {
/* Need to use software crypto for the test */
info->control.hw_key = NULL;
}
if (info->control.hw_key &&
(info->flags & IEEE80211_TX_CTL_DONTFRAG ||
tx->local->ops->set_frag_threshold) &&
!(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
/* hwaccel - with no need for SW-generated MMIC */
return TX_CONTINUE;
}
tail = MICHAEL_MIC_LEN;
if (!info->control.hw_key)
tail += TKIP_ICV_LEN;
if (WARN_ON(skb_tailroom(skb) < tail ||
skb_headroom(skb) < TKIP_IV_LEN))
return TX_DROP;
key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
mic = skb_put(skb, MICHAEL_MIC_LEN);
michael_mic(key, hdr, data, data_len, mic);
if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
mic[0]++;
return TX_CONTINUE;
}
ieee80211_rx_result
ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
{
u8 *data, *key = NULL;
size_t data_len;
unsigned int hdrlen;
u8 mic[MICHAEL_MIC_LEN];
struct sk_buff *skb = rx->skb;
struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
/*
* it makes no sense to check for MIC errors on anything other
* than data frames.
*/
if (!ieee80211_is_data_present(hdr->frame_control))
return RX_CONTINUE;
/*
* No way to verify the MIC if the hardware stripped it or
* the IV with the key index. In this case we have solely rely
* on the driver to set RX_FLAG_MMIC_ERROR in the event of a
* MIC failure report.
*/
if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
if (status->flag & RX_FLAG_MMIC_ERROR)
goto mic_fail;
if (!(status->flag & RX_FLAG_IV_STRIPPED))
goto update_iv;
return RX_CONTINUE;
}
/*
* Some hardware seems to generate Michael MIC failure reports; even
* though, the frame was not encrypted with TKIP and therefore has no
* MIC. Ignore the flag them to avoid triggering countermeasures.
*/
if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP ||
!(status->flag & RX_FLAG_DECRYPTED))
return RX_CONTINUE;
if (rx->sdata->vif.type == NL80211_IFTYPE_AP && rx->key->conf.keyidx) {
/*
* APs with pairwise keys should never receive Michael MIC
* errors for non-zero keyidx because these are reserved for
* group keys and only the AP is sending real multicast
* frames in the BSS. (
*/
return RX_DROP_UNUSABLE;
}
if (status->flag & RX_FLAG_MMIC_ERROR)
goto mic_fail;
hdrlen = ieee80211_hdrlen(hdr->frame_control);
if (skb->len < hdrlen + MICHAEL_MIC_LEN)
return RX_DROP_UNUSABLE;
data = skb->data + hdrlen;
data_len = skb->len - hdrlen - MICHAEL_MIC_LEN;
key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY];
michael_mic(key, hdr, data, data_len, mic);
if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0)
goto mic_fail;
/* remove Michael MIC from payload */
skb_trim(skb, skb->len - MICHAEL_MIC_LEN);
update_iv:
/* update IV in key information to be able to detect replays */
rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
return RX_CONTINUE;
mic_fail:
/*
* In some cases the key can be unset - e.g. a multicast packet, in
* a driver that supports HW encryption. Send up the key idx only if
* the key is set.
*/
mac80211_ev_michael_mic_failure(rx->sdata,
rx->key ? rx->key->conf.keyidx : -1,
(void *) skb->data, NULL, GFP_ATOMIC);
return RX_DROP_UNUSABLE;
}
