diff options
Diffstat (limited to 'net/ieee80211')
-rw-r--r-- | net/ieee80211/ieee80211_rx.c | 56 |
1 files changed, 50 insertions, 6 deletions
diff --git a/net/ieee80211/ieee80211_rx.c b/net/ieee80211/ieee80211_rx.c index 2759312a4204..d9265195656d 100644 --- a/net/ieee80211/ieee80211_rx.c +++ b/net/ieee80211/ieee80211_rx.c @@ -415,17 +415,16 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb, ieee->host_mc_decrypt : ieee->host_decrypt; if (can_be_decrypted) { - int idx = 0; if (skb->len >= hdrlen + 3) { /* Top two-bits of byte 3 are the key index */ - idx = skb->data[hdrlen + 3] >> 6; + keyidx = skb->data[hdrlen + 3] >> 6; } - /* ieee->crypt[] is WEP_KEY (4) in length. Given that idx - * is only allowed 2-bits of storage, no value of idx can - * be provided via above code that would result in idx + /* ieee->crypt[] is WEP_KEY (4) in length. Given that keyidx + * is only allowed 2-bits of storage, no value of keyidx can + * be provided via above code that would result in keyidx * being out of range */ - crypt = ieee->crypt[idx]; + crypt = ieee->crypt[keyidx]; #ifdef NOT_YET sta = NULL; @@ -655,6 +654,51 @@ int ieee80211_rx(struct ieee80211_device *ieee, struct sk_buff *skb, goto rx_dropped; } + /* If the frame was decrypted in hardware, we may need to strip off + * any security data (IV, ICV, etc) that was left behind */ + if (!can_be_decrypted && (fc & IEEE80211_FCTL_PROTECTED) && + ieee->host_strip_iv_icv) { + int trimlen = 0; + + /* Top two-bits of byte 3 are the key index */ + if (skb->len >= hdrlen + 3) + keyidx = skb->data[hdrlen + 3] >> 6; + + /* To strip off any security data which appears before the + * payload, we simply increase hdrlen (as the header gets + * chopped off immediately below). For the security data which + * appears after the payload, we use skb_trim. */ + + switch (ieee->sec.encode_alg[keyidx]) { + case SEC_ALG_WEP: + /* 4 byte IV */ + hdrlen += 4; + /* 4 byte ICV */ + trimlen = 4; + break; + case SEC_ALG_TKIP: + /* 4 byte IV, 4 byte ExtIV */ + hdrlen += 8; + /* 8 byte MIC, 4 byte ICV */ + trimlen = 12; + break; + case SEC_ALG_CCMP: + /* 8 byte CCMP header */ + hdrlen += 8; + /* 8 byte MIC */ + trimlen = 8; + break; + } + + if (skb->len < trimlen) + goto rx_dropped; + + __skb_trim(skb, skb->len - trimlen); + + if (skb->len < hdrlen) + goto rx_dropped; + } + /* skb: hdr + (possible reassembled) full plaintext payload */ payload = skb->data + hdrlen; |