Hi Stefan,
> On 2/08/2019, at 11:13 PM, Stefan Sperling <s...@stsp.name> wrote:
>
> This diff enables HW offload for WPA2 CCMP (AES) encrypted unicast
> frames in iwm(4). This is in preparation for Tx aggregation support.
Lightly tested on:
iwm0 at pci1 dev 0 function 0 "Intel Dual Band Wireless AC 7265" rev 0x69, msi
iwm0: hw rev 0x210, fw ver 16.242414.0, address xx:xx:xx:xx:xx:xx
pkg_add -u; download a few big files; ifconfig down; ifconfig up;
change network.
comments inline. supposing the async set keys command is a non-issue then,
for what it’s worth from this 802.11 novice, ok procter@
thanks!
Richard.
> WEP and WPA1/TKIP ciphers are still handled in software, which mirrors
> what the older iwn(4) driver is doing. We don't enable 11n at all with
> those ciphers (see ieee80211_ht_negotiate()), and we won't aggregate
> non-encrypted frames (see ieee80211_can_use_ampdu()).
>
> Based on an initial diff by procter@ and some code from iwn(4).
>
> Tested on 7260, 7265, 8260, and 8265 in bsd.rd upgrade and with pkg_add -u.
>
> ok?
>
> diff refs/heads/master refs/heads/iwm-hwcrypt
> blob - 7add1e9e682ef5e22169ec1e89a182cda1af7e2a
> blob + 839c0a0f8b3a62115ba6d5e15adfa63158475c86
> --- sys/dev/pci/if_iwm.c
> +++ sys/dev/pci/if_iwm.c
> @@ -367,6 +367,8 @@ int iwm_get_signal_strength(struct iwm_softc *,
> struct
> void iwm_rx_rx_phy_cmd(struct iwm_softc *, struct iwm_rx_packet *,
> struct iwm_rx_data *);
> int iwm_get_noise(const struct iwm_statistics_rx_non_phy *);
> +int iwm_ccmp_decap(struct iwm_softc *, struct mbuf *,
> + struct ieee80211_node *);
> void iwm_rx_rx_mpdu(struct iwm_softc *, struct iwm_rx_packet *,
> struct iwm_rx_data *);
> void iwm_enable_ht_cck_fallback(struct iwm_softc *, struct iwm_node *);
> @@ -448,6 +450,10 @@ int iwm_disassoc(struct iwm_softc *);
> int iwm_run(struct iwm_softc *);
> int iwm_run_stop(struct iwm_softc *);
> struct ieee80211_node *iwm_node_alloc(struct ieee80211com *);
> +int iwm_set_key(struct ieee80211com *, struct ieee80211_node *,
> + struct ieee80211_key *);
> +void iwm_delete_key(struct ieee80211com *,
> + struct ieee80211_node *, struct ieee80211_key *);
> void iwm_calib_timeout(void *);
> int iwm_media_change(struct ifnet *);
> void iwm_newstate_task(void *);
> @@ -3429,11 +3435,91 @@ iwm_get_noise(const struct iwm_statistics_rx_non_phy *
> return (nbant == 0) ? -127 : (total / nbant) - 107;
> }
>
> +int
> +iwm_ccmp_decap(struct iwm_softc *sc, struct mbuf *m, struct ieee80211_node
> *ni)
> +{
> + struct ieee80211com *ic = &sc->sc_ic;
> + struct ieee80211_key *k = &ni->ni_pairwise_key;
> + struct ieee80211_frame *wh;
> + struct ieee80211_rx_ba *ba;
> + uint64_t pn, *prsc;
> + uint8_t *ivp;
> + uint8_t tid;
> + int hdrlen, hasqos;
> +
> + wh = mtod(m, struct ieee80211_frame *);
> + hdrlen = ieee80211_get_hdrlen(wh);
> + ivp = (uint8_t *)wh + hdrlen;
> +
> + /* Check that ExtIV bit is be set. */
> + if (!(ivp[3] & IEEE80211_WEP_EXTIV)) {
> + DPRINTF(("CCMP decap ExtIV not set\n"));
> + return 1;
> + }
> + hasqos = ieee80211_has_qos(wh);
> + tid = hasqos ? ieee80211_get_qos(wh) & IEEE80211_QOS_TID : 0;
> + ba = hasqos ? &ni->ni_rx_ba[tid] : NULL;
> + prsc = &k->k_rsc[tid];
> +
> + /* Extract the 48-bit PN from the CCMP header. */
> + pn = (uint64_t)ivp[0] |
> + (uint64_t)ivp[1] << 8 |
> + (uint64_t)ivp[4] << 16 |
> + (uint64_t)ivp[5] << 24 |
> + (uint64_t)ivp[6] << 32 |
> + (uint64_t)ivp[7] << 40;
> + if (pn <= *prsc) {
> + if (hasqos && ba->ba_state == IEEE80211_BA_AGREED) {
> + /*
> + * This is an A-MPDU subframe.
> + * Such frames may be received out of order due to
> + * legitimate retransmissions of failed subframes
> + * in previous A-MPDUs. Duplicates will be handled
> + * in ieee80211_input() as part of A-MPDU reordering.
> + */
> + } else if (ieee80211_has_seq(wh)) {
> + /*
> + * Not necessarily a replayed frame since we did not
> + * check the sequence number of the 802.11 header yet.
> + */
> + int nrxseq, orxseq;
> +
> + nrxseq = letoh16(*(u_int16_t *)wh->i_seq) >>
> + IEEE80211_SEQ_SEQ_SHIFT;
> + if (hasqos)
> + orxseq = ni->ni_qos_rxseqs[tid];
> + else
> + orxseq = ni->ni_rxseq;
> + if (nrxseq < orxseq) {
> + DPRINTF(("CCMP replayed (n=%d < o=%d)\n",
> + nrxseq, orxseq));
> + ic->ic_stats.is_ccmp_replays++;
> + return 1;
> + }
> + } else {
> + DPRINTF(("CCMP replayed\n"));
> + ic->ic_stats.is_ccmp_replays++;
> + return 1;
> + }
> + }
> + /* Update last seen packet number. */
> + *prsc = pn;
> +
> + /* Clear Protected bit and strip IV. */
> + wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
> + memmove(mtod(m, caddr_t) + IEEE80211_CCMP_HDRLEN, wh, hdrlen);
> + m_adj(m, IEEE80211_CCMP_HDRLEN);
> + /* Strip MIC. */
> + m_adj(m, -IEEE80211_CCMP_MICLEN);
> + return 0;
> +}
> +
> void
> iwm_rx_rx_mpdu(struct iwm_softc *sc, struct iwm_rx_packet *pkt,
> struct iwm_rx_data *data)
> {
> struct ieee80211com *ic = &sc->sc_ic;
> + struct ifnet *ifp = IC2IFP(ic);
> struct ieee80211_frame *wh;
> struct ieee80211_node *ni;
> struct ieee80211_rxinfo rxi;
> @@ -3509,6 +3595,38 @@ iwm_rx_rx_mpdu(struct iwm_softc *sc, struct iwm_rx_pac
> rxi.rxi_rssi = rssi;
> rxi.rxi_tstamp = device_timestamp;
>
> + /* Handle hardware decryption. */
> + if (((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL)
> + && (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) &&
> + !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
> + (ni->ni_flags & IEEE80211_NODE_RXPROT) &&
> + ni->ni_pairwise_key.k_cipher == IEEE80211_CIPHER_CCMP) {
> + if ((rx_pkt_status & IWM_RX_MPDU_RES_STATUS_SEC_ENC_MSK) !=
> + IWM_RX_MPDU_RES_STATUS_SEC_CCM_ENC) {
> + ic->ic_stats.is_ccmp_dec_errs++;
> + ifp->if_ierrors++;
> + m_freem(m);
> + goto done;
> + }
> + /* Check whether decryption was successful or not. */
> + if ((rx_pkt_status &
> + (IWM_RX_MPDU_RES_STATUS_DEC_DONE |
> + IWM_RX_MPDU_RES_STATUS_MIC_OK)) !=
> + (IWM_RX_MPDU_RES_STATUS_DEC_DONE |
> + IWM_RX_MPDU_RES_STATUS_MIC_OK)) {
> + ic->ic_stats.is_ccmp_dec_errs++;
> + ifp->if_ierrors++;
> + m_freem(m);
> + goto done;
> + }
> + if (iwm_ccmp_decap(sc, m, ni) != 0) {
> + ifp->if_ierrors++;
> + m_freem(m);
> + goto done;
> + }
> + rxi.rxi_flags |= IEEE80211_RXI_HWDEC;
> + }
> +
> #if NBPFILTER > 0
> if (sc->sc_drvbpf != NULL) {
> struct mbuf mb;
> @@ -3566,6 +3684,7 @@ iwm_rx_rx_mpdu(struct iwm_softc *sc, struct iwm_rx_pac
> }
> #endif
> ieee80211_input(IC2IFP(ic), m, ni, &rxi);
> +done:
> /*
> * ieee80211_input() might have changed our BSS.
> * Restore ic_bss's channel if we are still in the same BSS.
> @@ -4218,6 +4337,7 @@ iwm_tx(struct iwm_softc *sc, struct mbuf *m, struct ie
> uint8_t tid, type;
> int i, totlen, err, pad;
> int hdrlen2, rtsthres = ic->ic_rtsthreshold;
> + uint8_t *ivp;
nit: shift declare up under const struct iwm_rate? (declare order by size)
>
> wh = mtod(m, struct ieee80211_frame *);
> hdrlen = ieee80211_get_hdrlen(wh);
> @@ -4278,16 +4398,48 @@ iwm_tx(struct iwm_softc *sc, struct mbuf *m, struct ie
> bpf_mtap(sc->sc_drvbpf, &mb, BPF_DIRECTION_OUT);
> }
> #endif
> + totlen = m->m_pkthdr.len;
>
> if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
> - k = ieee80211_get_txkey(ic, wh, ni);
> - if ((m = ieee80211_encrypt(ic, m, k)) == NULL)
> - return ENOBUFS;
> - /* 802.11 header may have moved. */
> - wh = mtod(m, struct ieee80211_frame *);
> + k = ieee80211_get_txkey(ic, wh, ni);
> + if (k->k_cipher != IEEE80211_CIPHER_CCMP) {
> + if ((m = ieee80211_encrypt(ic, m, k)) == NULL)
> + return ENOBUFS;
> +
> + /* 802.11 header may have moved. */
> + wh = mtod(m, struct ieee80211_frame *);
> + totlen = m->m_pkthdr.len;
> + } else {
> + /* HW appends CCMP MIC */
> + totlen += IEEE80211_CCMP_HDRLEN;
> + }
> }
> - totlen = m->m_pkthdr.len;
>
> + /* Copy 802.11 header in TX command. */
> + memcpy(((uint8_t *)tx) + sizeof(*tx), wh, hdrlen);
> +
> + if (k != NULL && k->k_cipher == IEEE80211_CIPHER_CCMP) {
> + /* Trim 802.11 header and prepend CCMP IV. */
> + m_adj(m, hdrlen - IEEE80211_CCMP_HDRLEN);
> + ivp = mtod(m, u_int8_t *);
> + k->k_tsc++; /* increment the 48-bit PN */
> + ivp[0] = k->k_tsc; /* PN0 */
> + ivp[1] = k->k_tsc >> 8; /* PN1 */
> + ivp[2] = 0; /* Rsvd */
> + ivp[3] = k->k_id << 6 | IEEE80211_WEP_EXTIV;
> + ivp[4] = k->k_tsc >> 16; /* PN2 */
> + ivp[5] = k->k_tsc >> 24; /* PN3 */
> + ivp[6] = k->k_tsc >> 32; /* PN4 */
> + ivp[7] = k->k_tsc >> 40; /* PN5 */
> +
> + tx->sec_ctl = IWM_TX_CMD_SEC_CCM;
> + memcpy(tx->key, k->k_key, k->k_len);
The ring warrants an explicit_bzero() on teardown to clear these keys
I think. The other drivers don’t do this that I can see; perhaps
best left for another diff.
> + } else {
> + /* Trim 802.11 header. */
> + m_adj(m, hdrlen);
> + tx->sec_ctl = 0;
> + }
> +
> flags = 0;
> if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
> flags |= IWM_TX_CMD_FLG_ACK;
> @@ -4339,17 +4491,10 @@ iwm_tx(struct iwm_softc *sc, struct mbuf *m, struct ie
> tx->dram_lsb_ptr = htole32(data->scratch_paddr);
> tx->dram_msb_ptr = iwm_get_dma_hi_addr(data->scratch_paddr);
>
> - /* Copy 802.11 header in TX command. */
> - memcpy(((uint8_t *)tx) + sizeof(*tx), wh, hdrlen);
> -
> flags |= IWM_TX_CMD_FLG_BT_DIS | IWM_TX_CMD_FLG_SEQ_CTL;
>
> - tx->sec_ctl = 0;
> tx->tx_flags |= htole32(flags);
>
> - /* Trim 802.11 header. */
> - m_adj(m, hdrlen);
> -
> err = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m,
> BUS_DMA_NOWAIT | BUS_DMA_WRITE);
> if (err && err != EFBIG) {
> @@ -5939,7 +6084,60 @@ iwm_node_alloc(struct ieee80211com *ic)
> return malloc(sizeof (struct iwm_node), M_DEVBUF, M_NOWAIT | M_ZERO);
> }
>
> +int
> +iwm_set_key(struct ieee80211com *ic, struct ieee80211_node *ni,
> + struct ieee80211_key *k)
> +{
> + struct iwm_softc *sc = ic->ic_softc;
> + struct iwm_add_sta_key_cmd cmd = { 0 };
> +
> + if ((k->k_flags & IEEE80211_KEY_GROUP) ||
> + k->k_cipher != IEEE80211_CIPHER_CCMP) {
> + /* Fallback to software crypto for other ciphers. */
> + return (ieee80211_set_key(ic, ni, k));
nit: bad indent
> + }
> +
> + cmd.key_flags = htole16(IWM_STA_KEY_FLG_CCM |
> + IWM_STA_KEY_FLG_WEP_KEY_MAP |
> + ((k->k_id << IWM_STA_KEY_FLG_KEYID_POS) &
> + IWM_STA_KEY_FLG_KEYID_MSK));
> + if (k->k_flags & IEEE80211_KEY_GROUP)
> + cmd.key_flags |= htole16(IWM_STA_KEY_MULTICAST);
> +
> + memcpy(cmd.key, k->k_key, k->k_len);
> + cmd.key_offset = 0;
> + cmd.sta_id = IWM_STATION_ID;
> +
> + return iwm_send_cmd_pdu(sc, IWM_ADD_STA_KEY, IWM_CMD_ASYNC,
> + sizeof(cmd), &cmd);
Might the async command open a race between loading keys and decrypting
received packets?
> +}
> +
> void
> +iwm_delete_key(struct ieee80211com *ic, struct ieee80211_node *ni,
> + struct ieee80211_key *k)
> +{
> + struct iwm_softc *sc = ic->ic_softc;
> + struct iwm_add_sta_key_cmd cmd = { 0 };
> +
> + if ((k->k_flags & IEEE80211_KEY_GROUP) ||
> + (k->k_cipher != IEEE80211_CIPHER_CCMP)) {
> + /* Fallback to software crypto for other ciphers. */
> + ieee80211_delete_key(ic, ni, k);
> + return;
> + }
> +
> + cmd.key_flags = htole16(IWM_STA_KEY_NOT_VALID |
> + IWM_STA_KEY_FLG_NO_ENC | IWM_STA_KEY_FLG_WEP_KEY_MAP |
> + ((k->k_id << IWM_STA_KEY_FLG_KEYID_POS) &
> + IWM_STA_KEY_FLG_KEYID_MSK));
> + memcpy(cmd.key, k->k_key, k->k_len);
> + cmd.key_offset = 0;
> + cmd.sta_id = IWM_STATION_ID;
> +
> + iwm_send_cmd_pdu(sc, IWM_ADD_STA_KEY, IWM_CMD_ASYNC, sizeof(cmd), &cmd);
> +}
> +
> +void
> iwm_calib_timeout(void *arg)
> {
> struct iwm_softc *sc = arg;
> @@ -7132,6 +7330,7 @@ iwm_notif_intr(struct iwm_softc *sc)
> case IWM_DTS_MEASUREMENT_NOTIFICATION:
> break;
>
> + case IWM_ADD_STA_KEY:
> case IWM_PHY_CONFIGURATION_CMD:
> case IWM_TX_ANT_CONFIGURATION_CMD:
> case IWM_ADD_STA:
> @@ -7814,6 +8013,8 @@ iwm_attach(struct device *parent, struct device *self,
>
> ic->ic_node_alloc = iwm_node_alloc;
> ic->ic_bgscan_start = iwm_bgscan;
> + ic->ic_set_key = iwm_set_key;
> + ic->ic_delete_key = iwm_delete_key;
>
> /* Override 802.11 state transition machine. */
> sc->sc_newstate = ic->ic_newstate;
> blob - da3d4bd1b26d2f88f469180075a00691739be6a5
> blob + def6715b6dc57708417d5dc3fb9d346b053e0197
> --- sys/dev/pci/if_iwmreg.h
> +++ sys/dev/pci/if_iwmreg.h
> @@ -641,11 +641,11 @@
> #define IWM_UCODE_TLV_API_LQ_SS_PARAMS (1 << 18)
> #define IWM_UCODE_TLV_API_EXT_SCAN_PRIORITY (1 << 24)
> #define IWM_UCODE_TLV_API_TX_POWER_CHAIN (1 << 27)
> -
> +#define IWM_UCODE_TLV_API_TKIP_MIC_KEYS (1 << 29)
> #define IWM_NUM_UCODE_TLV_API = 32
>
> #define IWM_UCODE_TLV_API_BITS \
> -
> "\020\10FRAGMENTED_SCAN\11WIFI_MCC_UPDATE\16WIDE_CMD_HDR\22LQ_SS_PARAMS\30EXT_SCAN_PRIO\33TX_POWER_CHAIN"
> +
> "\020\10FRAGMENTED_SCAN\11WIFI_MCC_UPDATE\16WIDE_CMD_HDR\22LQ_SS_PARAMS\30EXT_SCAN_PRIO\33TX_POWER_CHAIN\35TKIP_MIC_KEYS"
>
> /**
> * uCode capabilities
note: I copied this last hunk over from the linux driver; it’s unused by your
diff.
