int ieee80211_aes_ccm_decrypt(struct crypto_aead *tfm, struct sk_buff *skb, const u64 pn, size_t mic_len) { u8 aad[2 * AES_BLOCK_SIZE]; u8 b_0[AES_BLOCK_SIZE]; u8 *data, *mic; size_t data_len, hdr_len; struct ieee80211_hdr *hdr = (void *)skb->data; struct scatterlist sg[3]; char aead_req_data[sizeof(struct aead_request) + crypto_aead_reqsize(tfm)] __aligned(__alignof__(struct aead_request)); struct aead_request *aead_req = (void *) aead_req_data; hdr_len = ieee80211_hdrlen(hdr->frame_control); data_len = skb->len - hdr_len - mic_len; if (data_len <= 0) return -EINVAL; ccmp_special_blocks(hdr, hdr_len, pn, b_0, aad); memset(aead_req, 0, sizeof(aead_req_data)); mic = skb->data + skb->len - mic_len; data = skb->data + hdr_len; sg_init_table(sg, 3); sg_set_buf(&sg[0], &aad[2], be16_to_cpup((__be16 *)aad)); sg_set_buf(&sg[1], data, data_len); sg_set_buf(&sg[2], mic, mic_len); aead_request_set_tfm(aead_req, tfm); aead_request_set_crypt(aead_req, sg, sg, data_len + mic_len, b_0); aead_request_set_ad(aead_req, sg[0].length); return crypto_aead_decrypt(aead_req); }
static int ccmp_encrypt_skb(struct ieee80211_tx_data *tx, struct sk_buff *skb) { struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; struct ieee80211_key *key = tx->key; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); int hdrlen, len, tail; u8 *pos, *pn; int i; bool skip_hw; skip_hw = (tx->key->conf.flags & IEEE80211_KEY_FLAG_SW_MGMT) && ieee80211_is_mgmt(hdr->frame_control); if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) && !skip_hw) { /* hwaccel - with no need for preallocated room for CCMP * header or MIC fields */ info->control.hw_key = &tx->key->conf; return 0; } hdrlen = ieee80211_hdrlen(hdr->frame_control); len = skb->len - hdrlen; if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) tail = 0; else tail = CCMP_MIC_LEN; if (WARN_ON(skb_tailroom(skb) < tail || skb_headroom(skb) < CCMP_HDR_LEN)) return -1; pos = skb_push(skb, CCMP_HDR_LEN); memmove(pos, pos + CCMP_HDR_LEN, hdrlen); hdr = (struct ieee80211_hdr *) pos; pos += hdrlen; /* PN = PN + 1 */ pn = key->u.ccmp.tx_pn; for (i = CCMP_PN_LEN - 1; i >= 0; i--) { pn[i]++; if (pn[i]) break; } ccmp_pn2hdr(pos, pn, key->conf.keyidx); if ((key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) && !skip_hw) { /* hwaccel - with preallocated room for CCMP header */ info->control.hw_key = &tx->key->conf; return 0; } pos += CCMP_HDR_LEN; ccmp_special_blocks(skb, pn, key->u.ccmp.tx_crypto_buf, 0); ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, key->u.ccmp.tx_crypto_buf, pos, len, pos, skb_put(skb, CCMP_MIC_LEN)); return 0; }