Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * Copyright 2002-2004, Instant802 Networks, Inc.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

#include <linux/netdevice.h>

#include <linux/types.h>

#include <linux/slab.h>

#include <linux/skbuff.h>

#include <linux/compiler.h>

#include <net/mac80211.h>

#include "ieee80211_i.h"

#include "michael.h"

#include "tkip.h"

#include "aes_ccm.h"

#include "wpa.h"

static int ieee80211_get_hdr_info(const struct sk_buff *skb, u8 **sa, u8 **da,

                                  u8 *qos_tid, u8 **data, size_t *data_len)

{

        struct ieee80211_hdr *hdr;

        size_t hdrlen;

        u16 fc;

        int a4_included;

        u8 *pos;

        hdr = (struct ieee80211_hdr *) skb->data;

        fc = le16_to_cpu(hdr->frame_control);

        hdrlen = 24;

        if ((fc & (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) ==

            (IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS)) {

                hdrlen += ETH_ALEN;

                *sa = hdr->addr4;

                *da = hdr->addr3;

        } else if (fc & IEEE80211_FCTL_FROMDS) {

                *sa = hdr->addr3;

                *da = hdr->addr1;

        } else if (fc & IEEE80211_FCTL_TODS) {

                *sa = hdr->addr2;

                *da = hdr->addr3;

        } else {

                *sa = hdr->addr2;

                *da = hdr->addr1;

        }

        if (fc & 0x80)

                hdrlen += 2;

        *data = skb->data + hdrlen;

        *data_len = skb->len - hdrlen;

        a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==

                (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS);

        if ((fc & IEEE80211_FCTL_FTYPE) == IEEE80211_FTYPE_DATA &&

            fc & IEEE80211_STYPE_QOS_DATA) {

                pos = (u8 *) &hdr->addr4;

                if (a4_included)

                        pos += 6;

                *qos_tid = pos[0] & 0x0f;

                *qos_tid |= 0x80; /* qos_included flag */

        } else

                *qos_tid = 0;

        return skb->len < hdrlen ? -1 : 0;

}

ieee80211_txrx_result

ieee80211_tx_h_michael_mic_add(struct ieee80211_txrx_data *tx)

{

        u8 *data, *sa, *da, *key, *mic, qos_tid;

        size_t data_len;

        u16 fc;

        struct sk_buff *skb = tx->skb;

        int authenticator;

        int wpa_test = 0;

        fc = tx->fc;

        if (!tx->key || tx->key->conf.alg != ALG_TKIP || skb->len < 24 ||

            !WLAN_FC_DATA_PRESENT(fc))

                return TXRX_CONTINUE;

        if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len))

                return TXRX_DROP;

        if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&

            !(tx->flags & IEEE80211_TXRXD_FRAGMENTED) &&

            !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) &&

            !wpa_test) {

                /* hwaccel - with no need for preallocated room for Michael MIC

                 */

                return TXRX_CONTINUE;

        }

        if (skb_tailroom(skb) < MICHAEL_MIC_LEN) {

                I802_DEBUG_INC(tx->local->tx_expand_skb_head);

                if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN,

                                              MICHAEL_MIC_LEN + TKIP_ICV_LEN,

                                              GFP_ATOMIC))) {

                        printk(KERN_DEBUG "%s: failed to allocate more memory "

                               "for Michael MIC\n", tx->dev->name);

                        return TXRX_DROP;

                }

        }

#if 0

        authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */

#else

        authenticator = 1;

#endif

        key = &tx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_TX_MIC_KEY :

                                 ALG_TKIP_TEMP_AUTH_RX_MIC_KEY];

        mic = skb_put(skb, MICHAEL_MIC_LEN);

        michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);

        return TXRX_CONTINUE;

}

ieee80211_txrx_result

ieee80211_rx_h_michael_mic_verify(struct ieee80211_txrx_data *rx)

{

        u8 *data, *sa, *da, *key = NULL, qos_tid;

        size_t data_len;

        u16 fc;

        u8 mic[MICHAEL_MIC_LEN];

        struct sk_buff *skb = rx->skb;

        int authenticator = 1, wpa_test = 0;

        DECLARE_MAC_BUF(mac);

        fc = rx->fc;

        /*

         * No way to verify the MIC if the hardware stripped it

         */

        if (rx->u.rx.status->flag & RX_FLAG_MMIC_STRIPPED)

                return TXRX_CONTINUE;

        if (!rx->key || rx->key->conf.alg != ALG_TKIP ||

            !(rx->fc & IEEE80211_FCTL_PROTECTED) || !WLAN_FC_DATA_PRESENT(fc))

                return TXRX_CONTINUE;

        if (ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len)

            || data_len < MICHAEL_MIC_LEN)

                return TXRX_DROP;

        data_len -= MICHAEL_MIC_LEN;

#if 0

        authenticator = fc & IEEE80211_FCTL_TODS; /* FIX */

#else

        authenticator = 1;

#endif

        key = &rx->key->conf.key[authenticator ? ALG_TKIP_TEMP_AUTH_RX_MIC_KEY :

                                 ALG_TKIP_TEMP_AUTH_TX_MIC_KEY];

        michael_mic(key, da, sa, qos_tid & 0x0f, data, data_len, mic);

        if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0 || wpa_test) {

                if (!(rx->flags & IEEE80211_TXRXD_RXRA_MATCH))

                        return TXRX_DROP;

                printk(KERN_DEBUG "%s: invalid Michael MIC in data frame from "

                       "%s\n", rx->dev->name, print_mac(mac, sa));

                mac80211_ev_michael_mic_failure(rx->dev, rx->key->conf.keyidx,

                                                (void *) skb->data);

                return TXRX_DROP;

        }

        /* remove Michael MIC from payload */

        skb_trim(skb, skb->len - MICHAEL_MIC_LEN);

        /* update IV in key information to be able to detect replays */

        rx->key->u.tkip.iv32_rx[rx->u.rx.queue] = rx->u.rx.tkip_iv32;

        rx->key->u.tkip.iv16_rx[rx->u.rx.queue] = rx->u.rx.tkip_iv16;

        return TXRX_CONTINUE;

}

static int tkip_encrypt_skb(struct ieee80211_txrx_data *tx,

                            struct sk_buff *skb, int test)

{

        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;

        struct ieee80211_key *key = tx->key;

        int hdrlen, len, tailneed;

        u16 fc;

        u8 *pos;

        fc = le16_to_cpu(hdr->frame_control);

        hdrlen = ieee80211_get_hdrlen(fc);

        len = skb->len - hdrlen;

        if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)

                tailneed = 0;

        else

                tailneed = TKIP_ICV_LEN;

        if ((skb_headroom(skb) < TKIP_IV_LEN ||

             skb_tailroom(skb) < tailneed)) {

                I802_DEBUG_INC(tx->local->tx_expand_skb_head);

                if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed,

                                              GFP_ATOMIC)))

                        return -1;

        }

        pos = skb_push(skb, TKIP_IV_LEN);

        memmove(pos, pos + TKIP_IV_LEN, hdrlen);

        pos += hdrlen;

        /* Increase IV for the frame */

        key->u.tkip.iv16++;

        if (key->u.tkip.iv16 == 0)

                key->u.tkip.iv32++;

        if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {

                hdr = (struct ieee80211_hdr *)skb->data;

                /* hwaccel - with preallocated room for IV */

                ieee80211_tkip_add_iv(pos, key,

                                      (u8) (key->u.tkip.iv16 >> 8),

                                      (u8) (((key->u.tkip.iv16 >> 8) | 0x20) &

                                            0x7f),

                                      (u8) key->u.tkip.iv16);

                tx->u.tx.control->key_idx = tx->key->conf.hw_key_idx;

                return 0;

        }

        /* Add room for ICV */

        skb_put(skb, TKIP_ICV_LEN);

        hdr = (struct ieee80211_hdr *) skb->data;

        ieee80211_tkip_encrypt_data(tx->local->wep_tx_tfm,

                                    key, pos, len, hdr->addr2);

        return 0;

}

ieee80211_txrx_result

ieee80211_crypto_tkip_encrypt(struct ieee80211_txrx_data *tx)

{

        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;

        u16 fc;

        struct sk_buff *skb = tx->skb;

        int wpa_test = 0, test = 0;

        fc = le16_to_cpu(hdr->frame_control);

        if (!WLAN_FC_DATA_PRESENT(fc))

                return TXRX_CONTINUE;

        tx->u.tx.control->icv_len = TKIP_ICV_LEN;

        tx->u.tx.control->iv_len = TKIP_IV_LEN;

        ieee80211_tx_set_iswep(tx);

        if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&

            !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&

            !wpa_test) {

                /* hwaccel - with no need for preallocated room for IV/ICV */

                tx->u.tx.control->key_idx = tx->key->conf.hw_key_idx;

                return TXRX_CONTINUE;

        }

        if (tkip_encrypt_skb(tx, skb, test) < 0)

                return TXRX_DROP;

        if (tx->u.tx.extra_frag) {

                int i;

                for (i = 0; i < tx->u.tx.num_extra_frag; i++) {

                        if (tkip_encrypt_skb(tx, tx->u.tx.extra_frag[i], test)

                            < 0)

                                return TXRX_DROP;

                }

        }

        return TXRX_CONTINUE;

}

ieee80211_txrx_result

ieee80211_crypto_tkip_decrypt(struct ieee80211_txrx_data *rx)

{

        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;

        u16 fc;

        int hdrlen, res, hwaccel = 0, wpa_test = 0;

        struct ieee80211_key *key = rx->key;

        struct sk_buff *skb = rx->skb;

        DECLARE_MAC_BUF(mac);

        fc = le16_to_cpu(hdr->frame_control);

        hdrlen = ieee80211_get_hdrlen(fc);

        if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)

                return TXRX_CONTINUE;

        if (!rx->sta || skb->len - hdrlen < 12)

                return TXRX_DROP;

        if (rx->u.rx.status->flag & RX_FLAG_DECRYPTED) {

                if (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED) {

                        /*

                         * Hardware took care of all processing, including

                         * replay protection, and stripped the ICV/IV so

                         * we cannot do any checks here.

                         */

                        return TXRX_CONTINUE;

                }

                /* let TKIP code verify IV, but skip decryption */

                hwaccel = 1;

        }

        res = ieee80211_tkip_decrypt_data(rx->local->wep_rx_tfm,

                                          key, skb->data + hdrlen,

                                          skb->len - hdrlen, rx->sta->addr,

                                          hwaccel, rx->u.rx.queue,

                                          &rx->u.rx.tkip_iv32,

                                          &rx->u.rx.tkip_iv16);

        if (res != TKIP_DECRYPT_OK || wpa_test) {

#ifdef CONFIG_MAC80211_DEBUG

                if (net_ratelimit())

                        printk(KERN_DEBUG "%s: TKIP decrypt failed for RX "

                               "frame from %s (res=%d)\n", rx->dev->name,

                               print_mac(mac, rx->sta->addr), res);

#endif /* CONFIG_MAC80211_DEBUG */

                return TXRX_DROP;

        }

        /* Trim ICV */

        skb_trim(skb, skb->len - TKIP_ICV_LEN);

        /* Remove IV */

        memmove(skb->data + TKIP_IV_LEN, skb->data, hdrlen);

        skb_pull(skb, TKIP_IV_LEN);

        return TXRX_CONTINUE;

}

static void ccmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *b_0, u8 *aad,

                                int encrypted)

{

        u16 fc;

        int a4_included, qos_included;

        u8 qos_tid, *fc_pos, *data, *sa, *da;

        int len_a;

        size_t data_len;

        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;

        fc_pos = (u8 *) &hdr->frame_control;

        fc = fc_pos[0] ^ (fc_pos[1] << 8);

        a4_included = (fc & (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) ==

                (IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS);

        ieee80211_get_hdr_info(skb, &sa, &da, &qos_tid, &data, &data_len);

        data_len -= CCMP_HDR_LEN + (encrypted ? CCMP_MIC_LEN : 0);

        if (qos_tid & 0x80) {

                qos_included = 1;

                qos_tid &= 0x0f;

        } else

                qos_included = 0;

        /* First block, b_0 */

        b_0[0] = 0x59; /* flags: Adata: 1, M: 011, L: 001 */

        /* Nonce: QoS Priority | A2 | PN */

        b_0[1] = qos_tid;

        memcpy(&b_0[2], hdr->addr2, 6);

        memcpy(&b_0[8], pn, CCMP_PN_LEN);

        /* l(m) */

        b_0[14] = (data_len >> 8) & 0xff;

        b_0[15] = data_len & 0xff;

        /* AAD (extra authenticate-only data) / masked 802.11 header

         * FC | A1 | A2 | A3 | SC | [A4] | [QC] */

        len_a = a4_included ? 28 : 22;

        if (qos_included)

                len_a += 2;

        aad[0] = 0; /* (len_a >> 8) & 0xff; */

        aad[1] = len_a & 0xff;

        /* Mask FC: zero subtype b4 b5 b6 */

        aad[2] = fc_pos[0] & ~(BIT(4) | BIT(5) | BIT(6));

        /* Retry, PwrMgt, MoreData; set Protected */

        aad[3] = (fc_pos[1] & ~(BIT(3) | BIT(4) | BIT(5))) | BIT(6);

        memcpy(&aad[4], &hdr->addr1, 18);

        /* Mask Seq#, leave Frag# */

        aad[22] = *((u8 *) &hdr->seq_ctrl) & 0x0f;

        aad[23] = 0;

        if (a4_included) {

                memcpy(&aad[24], hdr->addr4, 6);

                aad[30] = 0;

                aad[31] = 0;

        } else

                memset(&aad[24], 0, 8);

        if (qos_included) {

                u8 *dpos = &aad[a4_included ? 30 : 24];

                /* Mask QoS Control field */

                dpos[0] = qos_tid;

                dpos[1] = 0;

        }

}

static inline void ccmp_pn2hdr(u8 *hdr, u8 *pn, int key_id)

{

        hdr[0] = pn[5];

        hdr[1] = pn[4];

        hdr[2] = 0;

        hdr[3] = 0x20 | (key_id << 6);

        hdr[4] = pn[3];

        hdr[5] = pn[2];

        hdr[6] = pn[1];

        hdr[7] = pn[0];

}

static inline int ccmp_hdr2pn(u8 *pn, u8 *hdr)

{

        pn[0] = hdr[7];

        pn[1] = hdr[6];

        pn[2] = hdr[5];

        pn[3] = hdr[4];

        pn[4] = hdr[1];

        pn[5] = hdr[0];

        return (hdr[3] >> 6) & 0x03;

}

static int ccmp_encrypt_skb(struct ieee80211_txrx_data *tx,

                            struct sk_buff *skb, int test)

{

        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;

        struct ieee80211_key *key = tx->key;

        int hdrlen, len, tailneed;

        u16 fc;

        u8 *pos, *pn, *b_0, *aad, *scratch;

        int i;

        scratch = key->u.ccmp.tx_crypto_buf;

        b_0 = scratch + 3 * AES_BLOCK_LEN;

        aad = scratch + 4 * AES_BLOCK_LEN;

        fc = le16_to_cpu(hdr->frame_control);

        hdrlen = ieee80211_get_hdrlen(fc);

        len = skb->len - hdrlen;

        if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)

                tailneed = 0;

        else

                tailneed = CCMP_MIC_LEN;

        if ((skb_headroom(skb) < CCMP_HDR_LEN ||

             skb_tailroom(skb) < tailneed)) {

                I802_DEBUG_INC(tx->local->tx_expand_skb_head);

                if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed,

                                              GFP_ATOMIC)))

                        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) {

                /* hwaccel - with preallocated room for CCMP header */

                tx->u.tx.control->key_idx = key->conf.hw_key_idx;

                return 0;

        }

        pos += CCMP_HDR_LEN;

        ccmp_special_blocks(skb, pn, b_0, aad, 0);

        ieee80211_aes_ccm_encrypt(key->u.ccmp.tfm, scratch, b_0, aad, pos, len,

                                  pos, skb_put(skb, CCMP_MIC_LEN));

        return 0;

}

ieee80211_txrx_result

ieee80211_crypto_ccmp_encrypt(struct ieee80211_txrx_data *tx)

{

        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;

        u16 fc;

        struct sk_buff *skb = tx->skb;

        int test = 0;

        fc = le16_to_cpu(hdr->frame_control);

        if (!WLAN_FC_DATA_PRESENT(fc))

                return TXRX_CONTINUE;

        tx->u.tx.control->icv_len = CCMP_MIC_LEN;

        tx->u.tx.control->iv_len = CCMP_HDR_LEN;

        ieee80211_tx_set_iswep(tx);

        if ((tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) &&

            !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {

                /* hwaccel - with no need for preallocated room for CCMP "

                 * header or MIC fields */

                tx->u.tx.control->key_idx = tx->key->conf.hw_key_idx;

                return TXRX_CONTINUE;

        }

        if (ccmp_encrypt_skb(tx, skb, test) < 0)

                return TXRX_DROP;

        if (tx->u.tx.extra_frag) {

                int i;

                for (i = 0; i < tx->u.tx.num_extra_frag; i++) {

                        if (ccmp_encrypt_skb(tx, tx->u.tx.extra_frag[i], test)

                            < 0)

                                return TXRX_DROP;

                }

        }

        return TXRX_CONTINUE;

}

ieee80211_txrx_result

ieee80211_crypto_ccmp_decrypt(struct ieee80211_txrx_data *rx)

{

        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) rx->skb->data;

        u16 fc;

        int hdrlen;

        struct ieee80211_key *key = rx->key;

        struct sk_buff *skb = rx->skb;

        u8 pn[CCMP_PN_LEN];

        int data_len;

        DECLARE_MAC_BUF(mac);

        fc = le16_to_cpu(hdr->frame_control);

        hdrlen = ieee80211_get_hdrlen(fc);

        if ((rx->fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA)

                return TXRX_CONTINUE;

        data_len = skb->len - hdrlen - CCMP_HDR_LEN - CCMP_MIC_LEN;

        if (!rx->sta || data_len < 0)

                return TXRX_DROP;

        if ((rx->u.rx.status->flag & RX_FLAG_DECRYPTED) &&

            (rx->u.rx.status->flag & RX_FLAG_IV_STRIPPED))

                return TXRX_CONTINUE;

        (void) ccmp_hdr2pn(pn, skb->data + hdrlen);

        if (memcmp(pn, key->u.ccmp.rx_pn[rx->u.rx.queue], CCMP_PN_LEN) <= 0) {

#ifdef CONFIG_MAC80211_DEBUG

                u8 *ppn = key->u.ccmp.rx_pn[rx->u.rx.queue];

                printk(KERN_DEBUG "%s: CCMP replay detected for RX frame from "

                       "%s (RX PN %02x%02x%02x%02x%02x%02x <= prev. PN "

                       "%02x%02x%02x%02x%02x%02x)\n", rx->dev->name,

                       print_mac(mac, rx->sta->addr),

                       pn[0], pn[1], pn[2], pn[3], pn[4], pn[5],

                       ppn[0], ppn[1], ppn[2], ppn[3], ppn[4], ppn[5]);

#endif /* CONFIG_MAC80211_DEBUG */

                key->u.ccmp.replays++;

                return TXRX_DROP;

        }

        if (!(rx->u.rx.status->flag & RX_FLAG_DECRYPTED)) {

                /* hardware didn't decrypt/verify MIC */

                u8 *scratch, *b_0, *aad;

                scratch = key->u.ccmp.rx_crypto_buf;

                b_0 = scratch + 3 * AES_BLOCK_LEN;

                aad = scratch + 4 * AES_BLOCK_LEN;

                ccmp_special_blocks(skb, pn, b_0, aad, 1);

                if (ieee80211_aes_ccm_decrypt(

                            key->u.ccmp.tfm, scratch, b_0, aad,

                            skb->data + hdrlen + CCMP_HDR_LEN, data_len,

                            skb->data + skb->len - CCMP_MIC_LEN,

                            skb->data + hdrlen + CCMP_HDR_LEN)) {

#ifdef CONFIG_MAC80211_DEBUG

                        if (net_ratelimit())

                                printk(KERN_DEBUG "%s: CCMP decrypt failed "

                                       "for RX frame from %s\n", rx->dev->name,

                                       print_mac(mac, rx->sta->addr));

#endif /* CONFIG_MAC80211_DEBUG */

                        return TXRX_DROP;

                }

        }

        memcpy(key->u.ccmp.rx_pn[rx->u.rx.queue], pn, CCMP_PN_LEN);

        /* Remove CCMP header and MIC */

        skb_trim(skb, skb->len - CCMP_MIC_LEN);