diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index b04a4378adcc..81241e18f3a4 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -2368,47 +2368,6 @@ ieee80211_rx_h_mgmt(struct ieee80211_rx_data *rx) return RX_QUEUED; } -static void ieee80211_rx_michael_mic_report(struct ieee80211_hdr *hdr, - struct ieee80211_rx_data *rx) -{ - int keyidx; - unsigned int hdrlen; - - hdrlen = ieee80211_hdrlen(hdr->frame_control); - if (rx->skb->len >= hdrlen + 4) - keyidx = rx->skb->data[hdrlen + 3] >> 6; - else - keyidx = -1; - - if (!rx->sta) { - /* - * Some hardware seem to generate incorrect Michael MIC - * reports; ignore them to avoid triggering countermeasures. - */ - return; - } - - if (!ieee80211_has_protected(hdr->frame_control)) - return; - - if (rx->sdata->vif.type == NL80211_IFTYPE_AP && 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; - } - - if (!ieee80211_is_data(hdr->frame_control) && - !ieee80211_is_auth(hdr->frame_control)) - return; - - mac80211_ev_michael_mic_failure(rx->sdata, keyidx, hdr, NULL, - GFP_ATOMIC); -} - /* TODO: use IEEE80211_RX_FRAGMENTED */ static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, struct ieee80211_rate *rate) @@ -2752,12 +2711,6 @@ static bool ieee80211_prepare_and_rx_handle(struct ieee80211_rx_data *rx, if (!prepares) return false; - if (status->flag & RX_FLAG_MMIC_ERROR) { - if (status->rx_flags & IEEE80211_RX_RA_MATCH) - ieee80211_rx_michael_mic_report(hdr, rx); - return false; - } - if (!consume) { skb = skb_copy(skb, GFP_ATOMIC); if (!skb) { diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c index f1765de2f4bf..9dc3b5f26e80 100644 --- a/net/mac80211/wpa.c +++ b/net/mac80211/wpa.c @@ -87,14 +87,50 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; - /* No way to verify the MIC if the hardware stripped it */ - if (status->flag & RX_FLAG_MMIC_STRIPPED) + /* + * 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; - if (!rx->key || rx->key->conf.cipher != WLAN_CIPHER_SUITE_TKIP || - !ieee80211_has_protected(hdr->frame_control) || - !ieee80211_is_data_present(hdr->frame_control)) + /* + * 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) @@ -102,27 +138,25 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) 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) { - 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; - } + 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->queue].iv32 = rx->tkip_iv32; rx->key->u.tkip.rx[rx->queue].iv16 = rx->tkip_iv16; return RX_CONTINUE; + +mic_fail: + mac80211_ev_michael_mic_failure(rx->sdata, rx->key->conf.keyidx, + (void *) skb->data, NULL, GFP_ATOMIC); + return RX_DROP_UNUSABLE; }