From 23edcc4147ad36f8d55f0eb79c21e245ffb9f211 Mon Sep 17 00:00:00 2001 From: David Kilroy Date: Thu, 21 Aug 2008 23:28:05 +0100 Subject: orinoco: Add MIC on TX and check on RX Use the MIC algorithm from the crypto subsystem. Signed-off-by: David Kilroy Signed-off-by: John W. Linville --- drivers/net/wireless/Kconfig | 2 + drivers/net/wireless/hermes.h | 7 ++ drivers/net/wireless/orinoco.c | 234 ++++++++++++++++++++++++++++++++++++++--- drivers/net/wireless/orinoco.h | 2 + 4 files changed, 229 insertions(+), 16 deletions(-) diff --git a/drivers/net/wireless/Kconfig b/drivers/net/wireless/Kconfig index ea7da7117f4..45bdf0b339b 100644 --- a/drivers/net/wireless/Kconfig +++ b/drivers/net/wireless/Kconfig @@ -336,6 +336,8 @@ config HERMES depends on (PPC_PMAC || PCI || PCMCIA) && WLAN_80211 select WIRELESS_EXT select FW_LOADER + select CRYPTO + select CRYPTO_MICHAEL_MIC ---help--- A driver for 802.11b wireless cards based on the "Hermes" or Intersil HFA384x (Prism 2) MAC controller. This includes the vast diff --git a/drivers/net/wireless/hermes.h b/drivers/net/wireless/hermes.h index 113f3f6cb2d..8b13c8fef3d 100644 --- a/drivers/net/wireless/hermes.h +++ b/drivers/net/wireless/hermes.h @@ -184,13 +184,18 @@ #define HERMES_RXSTAT_ERR (0x0003) #define HERMES_RXSTAT_BADCRC (0x0001) #define HERMES_RXSTAT_UNDECRYPTABLE (0x0002) +#define HERMES_RXSTAT_MIC (0x0010) /* Frame contains MIC */ #define HERMES_RXSTAT_MACPORT (0x0700) #define HERMES_RXSTAT_PCF (0x1000) /* Frame was received in CF period */ +#define HERMES_RXSTAT_MIC_KEY_ID (0x1800) /* MIC key used */ #define HERMES_RXSTAT_MSGTYPE (0xE000) #define HERMES_RXSTAT_1042 (0x2000) /* RFC-1042 frame */ #define HERMES_RXSTAT_TUNNEL (0x4000) /* bridge-tunnel encoded frame */ #define HERMES_RXSTAT_WMP (0x6000) /* Wavelan-II Management Protocol frame */ +/* Shift amount for key ID in RXSTAT and TXCTRL */ +#define HERMES_MIC_KEY_ID_SHIFT 11 + struct hermes_tx_descriptor { __le16 status; __le16 reserved1; @@ -209,6 +214,8 @@ struct hermes_tx_descriptor { #define HERMES_TXCTRL_TX_OK (0x0002) /* ?? interrupt on Tx complete */ #define HERMES_TXCTRL_TX_EX (0x0004) /* ?? interrupt on Tx exception */ #define HERMES_TXCTRL_802_11 (0x0008) /* We supply 802.11 header */ +#define HERMES_TXCTRL_MIC (0x0010) /* 802.3 + TKIP */ +#define HERMES_TXCTRL_MIC_KEY_ID (0x1800) /* MIC Key ID mask */ #define HERMES_TXCTRL_ALT_RTRY (0x0020) /* Inquiry constants and data types */ diff --git a/drivers/net/wireless/orinoco.c b/drivers/net/wireless/orinoco.c index 768b3945267..6a196c31de4 100644 --- a/drivers/net/wireless/orinoco.c +++ b/drivers/net/wireless/orinoco.c @@ -89,6 +89,9 @@ #include #include +#include +#include + #include "hermes_rid.h" #include "hermes_dld.h" #include "orinoco.h" @@ -243,6 +246,74 @@ struct hermes_rx_descriptor { static int __orinoco_program_rids(struct net_device *dev); static void __orinoco_set_multicast_list(struct net_device *dev); +/********************************************************************/ +/* Michael MIC crypto setup */ +/********************************************************************/ +#define MICHAEL_MIC_LEN 8 +static int orinoco_mic_init(struct orinoco_private *priv) +{ + priv->tx_tfm_mic = crypto_alloc_hash("michael_mic", 0, 0); + if (IS_ERR(priv->tx_tfm_mic)) { + printk(KERN_DEBUG "orinoco_mic_init: could not allocate " + "crypto API michael_mic\n"); + priv->tx_tfm_mic = NULL; + return -ENOMEM; + } + + priv->rx_tfm_mic = crypto_alloc_hash("michael_mic", 0, 0); + if (IS_ERR(priv->rx_tfm_mic)) { + printk(KERN_DEBUG "orinoco_mic_init: could not allocate " + "crypto API michael_mic\n"); + priv->rx_tfm_mic = NULL; + return -ENOMEM; + } + + return 0; +} + +static void orinoco_mic_free(struct orinoco_private *priv) +{ + if (priv->tx_tfm_mic) + crypto_free_hash(priv->tx_tfm_mic); + if (priv->rx_tfm_mic) + crypto_free_hash(priv->rx_tfm_mic); +} + +static int michael_mic(struct crypto_hash *tfm_michael, u8 *key, + u8 *da, u8 *sa, u8 priority, + u8 *data, size_t data_len, u8 *mic) +{ + struct hash_desc desc; + struct scatterlist sg[2]; + u8 hdr[ETH_HLEN + 2]; /* size of header + padding */ + + if (tfm_michael == NULL) { + printk(KERN_WARNING "michael_mic: tfm_michael == NULL\n"); + return -1; + } + + /* Copy header into buffer. We need the padding on the end zeroed */ + memcpy(&hdr[0], da, ETH_ALEN); + memcpy(&hdr[ETH_ALEN], sa, ETH_ALEN); + hdr[ETH_ALEN*2] = priority; + hdr[ETH_ALEN*2+1] = 0; + hdr[ETH_ALEN*2+2] = 0; + hdr[ETH_ALEN*2+3] = 0; + + /* Use scatter gather to MIC header and data in one go */ + sg_init_table(sg, 2); + sg_set_buf(&sg[0], hdr, sizeof(hdr)); + sg_set_buf(&sg[1], data, data_len); + + if (crypto_hash_setkey(tfm_michael, key, MIC_KEYLEN)) + return -1; + + desc.tfm = tfm_michael; + desc.flags = 0; + return crypto_hash_digest(&desc, sg, data_len + sizeof(hdr), + mic); +} + /********************************************************************/ /* Internal helper functions */ /********************************************************************/ @@ -764,7 +835,6 @@ static int orinoco_xmit(struct sk_buff *skb, struct net_device *dev) int err = 0; u16 txfid = priv->txfid; struct ethhdr *eh; - int data_off; int tx_control; unsigned long flags; @@ -797,10 +867,12 @@ static int orinoco_xmit(struct sk_buff *skb, struct net_device *dev) if (skb->len < ETH_HLEN) goto drop; - eh = (struct ethhdr *)skb->data; - tx_control = HERMES_TXCTRL_TX_OK | HERMES_TXCTRL_TX_EX; + if (priv->encode_alg == IW_ENCODE_ALG_TKIP) + tx_control |= (priv->tx_key << HERMES_MIC_KEY_ID_SHIFT) | + HERMES_TXCTRL_MIC; + if (priv->has_alt_txcntl) { /* WPA enabled firmwares have tx_cntl at the end of * the 802.11 header. So write zeroed descriptor and @@ -842,6 +914,8 @@ static int orinoco_xmit(struct sk_buff *skb, struct net_device *dev) HERMES_802_3_OFFSET - HERMES_802_11_OFFSET); } + eh = (struct ethhdr *)skb->data; + /* Encapsulate Ethernet-II frames */ if (ntohs(eh->h_proto) > ETH_DATA_LEN) { /* Ethernet-II frame */ struct header_struct { @@ -851,33 +925,65 @@ static int orinoco_xmit(struct sk_buff *skb, struct net_device *dev) /* Strip destination and source from the data */ skb_pull(skb, 2 * ETH_ALEN); - data_off = HERMES_802_2_OFFSET + sizeof(encaps_hdr); /* And move them to a separate header */ memcpy(&hdr.eth, eh, 2 * ETH_ALEN); hdr.eth.h_proto = htons(sizeof(encaps_hdr) + skb->len); memcpy(hdr.encap, encaps_hdr, sizeof(encaps_hdr)); - err = hermes_bap_pwrite(hw, USER_BAP, &hdr, sizeof(hdr), - txfid, HERMES_802_3_OFFSET); - if (err) { - if (net_ratelimit()) - printk(KERN_ERR "%s: Error %d writing packet " - "header to BAP\n", dev->name, err); - goto busy; + /* Insert the SNAP header */ + if (skb_headroom(skb) < sizeof(hdr)) { + printk(KERN_ERR + "%s: Not enough headroom for 802.2 headers %d\n", + dev->name, skb_headroom(skb)); + goto drop; } - } else { /* IEEE 802.3 frame */ - data_off = HERMES_802_3_OFFSET; + eh = (struct ethhdr *) skb_push(skb, sizeof(hdr)); + memcpy(eh, &hdr, sizeof(hdr)); } err = hermes_bap_pwrite(hw, USER_BAP, skb->data, skb->len, - txfid, data_off); + txfid, HERMES_802_3_OFFSET); if (err) { printk(KERN_ERR "%s: Error %d writing packet to BAP\n", dev->name, err); goto busy; } + /* Calculate Michael MIC */ + if (priv->encode_alg == IW_ENCODE_ALG_TKIP) { + u8 mic_buf[MICHAEL_MIC_LEN + 1]; + u8 *mic; + size_t offset; + size_t len; + + if (skb->len % 2) { + /* MIC start is on an odd boundary */ + mic_buf[0] = skb->data[skb->len - 1]; + mic = &mic_buf[1]; + offset = skb->len - 1; + len = MICHAEL_MIC_LEN + 1; + } else { + mic = &mic_buf[0]; + offset = skb->len; + len = MICHAEL_MIC_LEN; + } + + michael_mic(priv->tx_tfm_mic, + priv->tkip_key[priv->tx_key].tx_mic, + eh->h_dest, eh->h_source, 0 /* priority */, + skb->data + ETH_HLEN, skb->len - ETH_HLEN, mic); + + /* Write the MIC */ + err = hermes_bap_pwrite(hw, USER_BAP, &mic_buf[0], len, + txfid, HERMES_802_3_OFFSET + offset); + if (err) { + printk(KERN_ERR "%s: Error %d writing MIC to BAP\n", + dev->name, err); + goto busy; + } + } + /* Finally, we actually initiate the send */ netif_stop_queue(dev); @@ -892,7 +998,7 @@ static int orinoco_xmit(struct sk_buff *skb, struct net_device *dev) } dev->trans_start = jiffies; - stats->tx_bytes += data_off + skb->len; + stats->tx_bytes += HERMES_802_3_OFFSET + skb->len; goto ok; drop: @@ -1172,6 +1278,25 @@ static void orinoco_rx_monitor(struct net_device *dev, u16 rxfid, stats->rx_dropped++; } +/* Get tsc from the firmware */ +static int orinoco_hw_get_tkip_iv(struct orinoco_private *priv, int key, + u8 *tsc) +{ + hermes_t *hw = &priv->hw; + int err = 0; + u8 tsc_arr[4][IW_ENCODE_SEQ_MAX_SIZE]; + + if ((key < 0) || (key > 4)) + return -EINVAL; + + err = hermes_read_ltv(hw, USER_BAP, HERMES_RID_CURRENT_TKIP_IV, + sizeof(tsc_arr), NULL, &tsc_arr); + if (!err) + memcpy(tsc, &tsc_arr[key][0], sizeof(tsc_arr[0])); + + return err; +} + static void __orinoco_ev_rx(struct net_device *dev, hermes_t *hw) { struct orinoco_private *priv = netdev_priv(dev); @@ -1240,6 +1365,11 @@ static void __orinoco_ev_rx(struct net_device *dev, hermes_t *hw) goto update_stats; } + /* Payload size does not include Michael MIC. Increase payload + * size to read it together with the data. */ + if (status & HERMES_RXSTAT_MIC) + length += MICHAEL_MIC_LEN; + /* We need space for the packet data itself, plus an ethernet header, plus 2 bytes so we can align the IP header on a 32bit boundary, plus 1 byte so we can read in odd length @@ -1303,6 +1433,63 @@ static void orinoco_rx(struct net_device *dev, length = le16_to_cpu(desc->data_len); fc = le16_to_cpu(desc->frame_ctl); + /* Calculate and check MIC */ + if (status & HERMES_RXSTAT_MIC) { + int key_id = ((status & HERMES_RXSTAT_MIC_KEY_ID) >> + HERMES_MIC_KEY_ID_SHIFT); + u8 mic[MICHAEL_MIC_LEN]; + u8 *rxmic; + u8 *src = (fc & IEEE80211_FCTL_FROMDS) ? + desc->addr3 : desc->addr2; + + /* Extract Michael MIC from payload */ + rxmic = skb->data + skb->len - MICHAEL_MIC_LEN; + + skb_trim(skb, skb->len - MICHAEL_MIC_LEN); + length -= MICHAEL_MIC_LEN; + + michael_mic(priv->rx_tfm_mic, + priv->tkip_key[key_id].rx_mic, + desc->addr1, + src, + 0, /* priority or QoS? */ + skb->data, + skb->len, + &mic[0]); + + if (memcmp(mic, rxmic, + MICHAEL_MIC_LEN)) { + union iwreq_data wrqu; + struct iw_michaelmicfailure wxmic; + DECLARE_MAC_BUF(mac); + + printk(KERN_WARNING "%s: " + "Invalid Michael MIC in data frame from %s, " + "using key %i\n", + dev->name, print_mac(mac, src), key_id); + + /* TODO: update stats */ + + /* Notify userspace */ + memset(&wxmic, 0, sizeof(wxmic)); + wxmic.flags = key_id & IW_MICFAILURE_KEY_ID; + wxmic.flags |= (desc->addr1[0] & 1) ? + IW_MICFAILURE_GROUP : IW_MICFAILURE_PAIRWISE; + wxmic.src_addr.sa_family = ARPHRD_ETHER; + memcpy(wxmic.src_addr.sa_data, src, ETH_ALEN); + + (void) orinoco_hw_get_tkip_iv(priv, key_id, + &wxmic.tsc[0]); + + memset(&wrqu, 0, sizeof(wrqu)); + wrqu.data.length = sizeof(wxmic); + wireless_send_event(dev, IWEVMICHAELMICFAILURE, &wrqu, + (char *) &wxmic); + + goto drop; + } + } + /* Handle decapsulation * In most cases, the firmware tell us about SNAP frames. * For some reason, the SNAP frames sent by LinkSys APs @@ -1342,6 +1529,11 @@ static void orinoco_rx(struct net_device *dev, stats->rx_bytes += length; return; + + drop: + dev_kfree_skb(skb); + stats->rx_errors++; + stats->rx_dropped++; } static void orinoco_rx_isr_tasklet(unsigned long data) @@ -3112,8 +3304,14 @@ static int orinoco_init(struct net_device *dev) else printk("40-bit key\n"); } - if (priv->has_wpa) + if (priv->has_wpa) { printk(KERN_DEBUG "%s: WPA-PSK supported\n", dev->name); + if (orinoco_mic_init(priv)) { + printk(KERN_ERR "%s: Failed to setup MIC crypto " + "algorithm. Disabling WPA support\n", dev->name); + priv->has_wpa = 0; + } + } /* Now we have the firmware capabilities, allocate appropiate * sized scan buffers */ @@ -3292,6 +3490,9 @@ struct net_device dev->set_multicast_list = orinoco_set_multicast_list; /* we use the default eth_mac_addr for setting the MAC addr */ + /* Reserve space in skb for the SNAP header */ + dev->hard_header_len += ENCAPS_OVERHEAD; + /* Set up default callbacks */ dev->open = orinoco_open; dev->stop = orinoco_stop; @@ -3327,6 +3528,7 @@ void free_orinocodev(struct net_device *dev) tasklet_kill(&priv->rx_tasklet); priv->wpa_ie_len = 0; kfree(priv->wpa_ie); + orinoco_mic_free(priv); orinoco_bss_data_free(priv); free_netdev(dev); } diff --git a/drivers/net/wireless/orinoco.h b/drivers/net/wireless/orinoco.h index e0c9be3daa3..981570bd3b9 100644 --- a/drivers/net/wireless/orinoco.h +++ b/drivers/net/wireless/orinoco.h @@ -158,6 +158,8 @@ struct orinoco_private { int wpa_ie_len; struct orinoco_tkip_key tkip_key[ORINOCO_MAX_KEYS]; + struct crypto_hash *rx_tfm_mic; + struct crypto_hash *tx_tfm_mic; unsigned int wpa_enabled:1; unsigned int tkip_cm_active:1; -- cgit v1.2.3