From 56c52da2d554f081e8fce58ecbcf6a40c605b95b Mon Sep 17 00:00:00 2001 From: Jouni Malinen Date: Sat, 24 Jan 2015 19:52:08 +0200 Subject: [PATCH] mac80111: Add BIP-CMAC-256 cipher This allows mac80211 to configure BIP-CMAC-256 to the driver and also use software-implementation within mac80211 when the driver does not support this with hardware accelaration. Signed-off-by: Jouni Malinen Signed-off-by: Johannes Berg --- include/linux/ieee80211.h | 9 ++++ net/mac80211/aes_cmac.c | 34 ++++++++++---- net/mac80211/aes_cmac.h | 5 ++- net/mac80211/cfg.c | 2 + net/mac80211/debugfs_key.c | 4 ++ net/mac80211/key.c | 14 +++++- net/mac80211/main.c | 13 +++--- net/mac80211/rx.c | 21 ++++++--- net/mac80211/tx.c | 3 ++ net/mac80211/wpa.c | 92 ++++++++++++++++++++++++++++++++++++++ net/mac80211/wpa.h | 4 ++ 11 files changed, 180 insertions(+), 21 deletions(-) diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h index dbf417bf25bf..b9c7897dc566 100644 --- a/include/linux/ieee80211.h +++ b/include/linux/ieee80211.h @@ -1017,6 +1017,15 @@ struct ieee80211_mmie { u8 mic[8]; } __packed; +/* Management MIC information element (IEEE 802.11w) for GMAC and CMAC-256 */ +struct ieee80211_mmie_16 { + u8 element_id; + u8 length; + __le16 key_id; + u8 sequence_number[6]; + u8 mic[16]; +} __packed; + struct ieee80211_vendor_ie { u8 element_id; u8 len; diff --git a/net/mac80211/aes_cmac.c b/net/mac80211/aes_cmac.c index 9b9009f99551..4192806be3d3 100644 --- a/net/mac80211/aes_cmac.c +++ b/net/mac80211/aes_cmac.c @@ -18,8 +18,8 @@ #include "key.h" #include "aes_cmac.h" -#define AES_CMAC_KEY_LEN 16 #define CMAC_TLEN 8 /* CMAC TLen = 64 bits (8 octets) */ +#define CMAC_TLEN_256 16 /* CMAC TLen = 128 bits (16 octets) */ #define AAD_LEN 20 @@ -35,9 +35,9 @@ static void gf_mulx(u8 *pad) pad[AES_BLOCK_SIZE - 1] ^= 0x87; } - -static void aes_128_cmac_vector(struct crypto_cipher *tfm, size_t num_elem, - const u8 *addr[], const size_t *len, u8 *mac) +static void aes_cmac_vector(struct crypto_cipher *tfm, size_t num_elem, + const u8 *addr[], const size_t *len, u8 *mac, + size_t mac_len) { u8 cbc[AES_BLOCK_SIZE], pad[AES_BLOCK_SIZE]; const u8 *pos, *end; @@ -88,7 +88,7 @@ static void aes_128_cmac_vector(struct crypto_cipher *tfm, size_t num_elem, for (i = 0; i < AES_BLOCK_SIZE; i++) pad[i] ^= cbc[i]; crypto_cipher_encrypt_one(tfm, pad, pad); - memcpy(mac, pad, CMAC_TLEN); + memcpy(mac, pad, mac_len); } @@ -107,17 +107,35 @@ void ieee80211_aes_cmac(struct crypto_cipher *tfm, const u8 *aad, addr[2] = zero; len[2] = CMAC_TLEN; - aes_128_cmac_vector(tfm, 3, addr, len, mic); + aes_cmac_vector(tfm, 3, addr, len, mic, CMAC_TLEN); } +void ieee80211_aes_cmac_256(struct crypto_cipher *tfm, const u8 *aad, + const u8 *data, size_t data_len, u8 *mic) +{ + const u8 *addr[3]; + size_t len[3]; + u8 zero[CMAC_TLEN_256]; + + memset(zero, 0, CMAC_TLEN_256); + addr[0] = aad; + len[0] = AAD_LEN; + addr[1] = data; + len[1] = data_len - CMAC_TLEN_256; + addr[2] = zero; + len[2] = CMAC_TLEN_256; + + aes_cmac_vector(tfm, 3, addr, len, mic, CMAC_TLEN_256); +} -struct crypto_cipher *ieee80211_aes_cmac_key_setup(const u8 key[]) +struct crypto_cipher *ieee80211_aes_cmac_key_setup(const u8 key[], + size_t key_len) { struct crypto_cipher *tfm; tfm = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); if (!IS_ERR(tfm)) - crypto_cipher_setkey(tfm, key, AES_CMAC_KEY_LEN); + crypto_cipher_setkey(tfm, key, key_len); return tfm; } diff --git a/net/mac80211/aes_cmac.h b/net/mac80211/aes_cmac.h index 0ce6487af795..3702041f44fd 100644 --- a/net/mac80211/aes_cmac.h +++ b/net/mac80211/aes_cmac.h @@ -11,9 +11,12 @@ #include -struct crypto_cipher *ieee80211_aes_cmac_key_setup(const u8 key[]); +struct crypto_cipher *ieee80211_aes_cmac_key_setup(const u8 key[], + size_t key_len); void ieee80211_aes_cmac(struct crypto_cipher *tfm, const u8 *aad, const u8 *data, size_t data_len, u8 *mic); +void ieee80211_aes_cmac_256(struct crypto_cipher *tfm, const u8 *aad, + const u8 *data, size_t data_len, u8 *mic); void ieee80211_aes_cmac_key_free(struct crypto_cipher *tfm); #endif /* AES_CMAC_H */ diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index ef84441c119c..b7e528bbecce 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -164,6 +164,7 @@ static int ieee80211_add_key(struct wiphy *wiphy, struct net_device *dev, case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: break; @@ -362,6 +363,7 @@ static int ieee80211_get_key(struct wiphy *wiphy, struct net_device *dev, params.seq_len = 6; break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: pn64 = atomic64_read(&key->u.aes_cmac.tx_pn); seq[0] = pn64; seq[1] = pn64 >> 8; diff --git a/net/mac80211/debugfs_key.c b/net/mac80211/debugfs_key.c index 64de07b16092..d1b60eb014a8 100644 --- a/net/mac80211/debugfs_key.c +++ b/net/mac80211/debugfs_key.c @@ -101,6 +101,7 @@ static ssize_t key_tx_spec_read(struct file *file, char __user *userbuf, (u8)(pn >> 16), (u8)(pn >> 8), (u8)pn); break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: pn = atomic64_read(&key->u.aes_cmac.tx_pn); len = scnprintf(buf, sizeof(buf), "%02x%02x%02x%02x%02x%02x\n", (u8)(pn >> 40), (u8)(pn >> 32), (u8)(pn >> 24), @@ -153,6 +154,7 @@ static ssize_t key_rx_spec_read(struct file *file, char __user *userbuf, len = p - buf; break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: rpn = key->u.aes_cmac.rx_pn; p += scnprintf(p, sizeof(buf)+buf-p, "%02x%02x%02x%02x%02x%02x\n", @@ -191,6 +193,7 @@ static ssize_t key_replays_read(struct file *file, char __user *userbuf, len = scnprintf(buf, sizeof(buf), "%u\n", key->u.ccmp.replays); break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: len = scnprintf(buf, sizeof(buf), "%u\n", key->u.aes_cmac.replays); break; @@ -214,6 +217,7 @@ static ssize_t key_icverrors_read(struct file *file, char __user *userbuf, switch (key->conf.cipher) { case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: len = scnprintf(buf, sizeof(buf), "%u\n", key->u.aes_cmac.icverrors); break; diff --git a/net/mac80211/key.c b/net/mac80211/key.c index 83c61085c3f0..7ceea9d9fcd2 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -165,6 +165,7 @@ static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key) case WLAN_CIPHER_SUITE_CCMP: case WLAN_CIPHER_SUITE_CCMP_256: case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: /* all of these we can do in software - if driver can */ @@ -417,8 +418,12 @@ ieee80211_key_alloc(u32 cipher, int idx, size_t key_len, } break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: key->conf.iv_len = 0; - key->conf.icv_len = sizeof(struct ieee80211_mmie); + if (cipher == WLAN_CIPHER_SUITE_AES_CMAC) + key->conf.icv_len = sizeof(struct ieee80211_mmie); + else + key->conf.icv_len = sizeof(struct ieee80211_mmie_16); if (seq) for (j = 0; j < IEEE80211_CMAC_PN_LEN; j++) key->u.aes_cmac.rx_pn[j] = @@ -428,7 +433,7 @@ ieee80211_key_alloc(u32 cipher, int idx, size_t key_len, * it does not need to be initialized for every packet. */ key->u.aes_cmac.tfm = - ieee80211_aes_cmac_key_setup(key_data); + ieee80211_aes_cmac_key_setup(key_data, key_len); if (IS_ERR(key->u.aes_cmac.tfm)) { err = PTR_ERR(key->u.aes_cmac.tfm); kfree(key); @@ -481,6 +486,7 @@ static void ieee80211_key_free_common(struct ieee80211_key *key) ieee80211_aes_key_free(key->u.ccmp.tfm); break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm); break; case WLAN_CIPHER_SUITE_GCMP: @@ -804,6 +810,7 @@ void ieee80211_get_key_tx_seq(struct ieee80211_key_conf *keyconf, seq->ccmp.pn[0] = pn64 >> 40; break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: pn64 = atomic64_read(&key->u.aes_cmac.tx_pn); seq->ccmp.pn[5] = pn64; seq->ccmp.pn[4] = pn64 >> 8; @@ -854,6 +861,7 @@ void ieee80211_get_key_rx_seq(struct ieee80211_key_conf *keyconf, memcpy(seq->ccmp.pn, pn, IEEE80211_CCMP_PN_LEN); break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: if (WARN_ON(tid != 0)) return; pn = key->u.aes_cmac.rx_pn; @@ -897,6 +905,7 @@ void ieee80211_set_key_tx_seq(struct ieee80211_key_conf *keyconf, atomic64_set(&key->u.ccmp.tx_pn, pn64); break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: pn64 = (u64)seq->aes_cmac.pn[5] | ((u64)seq->aes_cmac.pn[4] << 8) | ((u64)seq->aes_cmac.pn[3] << 16) | @@ -948,6 +957,7 @@ void ieee80211_set_key_rx_seq(struct ieee80211_key_conf *keyconf, memcpy(pn, seq->ccmp.pn, IEEE80211_CCMP_PN_LEN); break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: if (WARN_ON(tid != 0)) return; pn = key->u.aes_cmac.rx_pn; diff --git a/net/mac80211/main.c b/net/mac80211/main.c index a5ad2d5bb29b..053a17c5023a 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -671,7 +671,8 @@ static int ieee80211_init_cipher_suites(struct ieee80211_local *local) WLAN_CIPHER_SUITE_GCMP_256, /* keep last -- depends on hw flags! */ - WLAN_CIPHER_SUITE_AES_CMAC + WLAN_CIPHER_SUITE_AES_CMAC, + WLAN_CIPHER_SUITE_BIP_CMAC_256, }; if (local->hw.flags & IEEE80211_HW_SW_CRYPTO_CONTROL || @@ -710,7 +711,7 @@ static int ieee80211_init_cipher_suites(struct ieee80211_local *local) local->hw.wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites); if (!have_mfp) - local->hw.wiphy->n_cipher_suites--; + local->hw.wiphy->n_cipher_suites -= 2; if (!have_wep) { local->hw.wiphy->cipher_suites += 2; @@ -736,9 +737,9 @@ static int ieee80211_init_cipher_suites(struct ieee80211_local *local) if (have_wep) n_suites += 2; - /* check if we have AES_CMAC */ + /* check if we have AES_CMAC, BIP-CMAC-256 */ if (have_mfp) - n_suites++; + n_suites += 2; suites = kmalloc(sizeof(u32) * n_suites, GFP_KERNEL); if (!suites) @@ -755,8 +756,10 @@ static int ieee80211_init_cipher_suites(struct ieee80211_local *local) suites[w++] = WLAN_CIPHER_SUITE_WEP104; } - if (have_mfp) + if (have_mfp) { suites[w++] = WLAN_CIPHER_SUITE_AES_CMAC; + suites[w++] = WLAN_CIPHER_SUITE_BIP_CMAC_256; + } for (r = 0; r < local->hw.n_cipher_schemes; r++) suites[w++] = cs[r].cipher; diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index e8c6ba5ce70b..93ebc9525478 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -647,6 +647,7 @@ static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) { struct ieee80211_mgmt *hdr = (struct ieee80211_mgmt *) skb->data; struct ieee80211_mmie *mmie; + struct ieee80211_mmie_16 *mmie16; if (skb->len < 24 + sizeof(*mmie) || !is_multicast_ether_addr(hdr->da)) return -1; @@ -656,11 +657,18 @@ static int ieee80211_get_mmie_keyidx(struct sk_buff *skb) mmie = (struct ieee80211_mmie *) (skb->data + skb->len - sizeof(*mmie)); - if (mmie->element_id != WLAN_EID_MMIE || - mmie->length != sizeof(*mmie) - 2) - return -1; - - return le16_to_cpu(mmie->key_id); + if (mmie->element_id == WLAN_EID_MMIE && + mmie->length == sizeof(*mmie) - 2) + return le16_to_cpu(mmie->key_id); + + mmie16 = (struct ieee80211_mmie_16 *) + (skb->data + skb->len - sizeof(*mmie16)); + if (skb->len >= 24 + sizeof(*mmie16) && + mmie16->element_id == WLAN_EID_MMIE && + mmie16->length == sizeof(*mmie16) - 2) + return le16_to_cpu(mmie16->key_id); + + return -1; } static int iwl80211_get_cs_keyid(const struct ieee80211_cipher_scheme *cs, @@ -1660,6 +1668,9 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) case WLAN_CIPHER_SUITE_AES_CMAC: result = ieee80211_crypto_aes_cmac_decrypt(rx); break; + case WLAN_CIPHER_SUITE_BIP_CMAC_256: + result = ieee80211_crypto_aes_cmac_256_decrypt(rx); + break; case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: result = ieee80211_crypto_gcmp_decrypt(rx); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index be57e0afd019..909c27be1fdc 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -639,6 +639,7 @@ ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx) ieee80211_is_mgmt(hdr->frame_control); break; case WLAN_CIPHER_SUITE_AES_CMAC: + case WLAN_CIPHER_SUITE_BIP_CMAC_256: if (!ieee80211_is_mgmt(hdr->frame_control)) tx->key = NULL; break; @@ -1021,6 +1022,8 @@ ieee80211_tx_h_encrypt(struct ieee80211_tx_data *tx) tx, IEEE80211_CCMP_256_MIC_LEN); case WLAN_CIPHER_SUITE_AES_CMAC: return ieee80211_crypto_aes_cmac_encrypt(tx); + case WLAN_CIPHER_SUITE_BIP_CMAC_256: + return ieee80211_crypto_aes_cmac_256_encrypt(tx); case WLAN_CIPHER_SUITE_GCMP: case WLAN_CIPHER_SUITE_GCMP_256: return ieee80211_crypto_gcmp_encrypt(tx); diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c index ae654de9782a..549af118de9f 100644 --- a/net/mac80211/wpa.c +++ b/net/mac80211/wpa.c @@ -955,6 +955,48 @@ ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx) return TX_CONTINUE; } +ieee80211_tx_result +ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx) +{ + struct sk_buff *skb; + struct ieee80211_tx_info *info; + struct ieee80211_key *key = tx->key; + struct ieee80211_mmie_16 *mmie; + u8 aad[20]; + u64 pn64; + + if (WARN_ON(skb_queue_len(&tx->skbs) != 1)) + return TX_DROP; + + skb = skb_peek(&tx->skbs); + + info = IEEE80211_SKB_CB(skb); + + if (info->control.hw_key) + return TX_CONTINUE; + + if (WARN_ON(skb_tailroom(skb) < sizeof(*mmie))) + return TX_DROP; + + mmie = (struct ieee80211_mmie_16 *)skb_put(skb, sizeof(*mmie)); + mmie->element_id = WLAN_EID_MMIE; + mmie->length = sizeof(*mmie) - 2; + mmie->key_id = cpu_to_le16(key->conf.keyidx); + + /* PN = PN + 1 */ + pn64 = atomic64_inc_return(&key->u.aes_cmac.tx_pn); + + bip_ipn_set64(mmie->sequence_number, pn64); + + bip_aad(skb, aad); + + /* MIC = AES-256-CMAC(IGTK, AAD || Management Frame Body || MMIE, 128) + */ + ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, + skb->data + 24, skb->len - 24, mmie->mic); + + return TX_CONTINUE; +} ieee80211_rx_result ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) @@ -1006,6 +1048,56 @@ ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) return RX_CONTINUE; } +ieee80211_rx_result +ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) +{ + struct sk_buff *skb = rx->skb; + struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); + struct ieee80211_key *key = rx->key; + struct ieee80211_mmie_16 *mmie; + u8 aad[20], mic[16], ipn[6]; + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; + + if (!ieee80211_is_mgmt(hdr->frame_control)) + return RX_CONTINUE; + + /* management frames are already linear */ + + if (skb->len < 24 + sizeof(*mmie)) + return RX_DROP_UNUSABLE; + + mmie = (struct ieee80211_mmie_16 *) + (skb->data + skb->len - sizeof(*mmie)); + if (mmie->element_id != WLAN_EID_MMIE || + mmie->length != sizeof(*mmie) - 2) + return RX_DROP_UNUSABLE; /* Invalid MMIE */ + + bip_ipn_swap(ipn, mmie->sequence_number); + + if (memcmp(ipn, key->u.aes_cmac.rx_pn, 6) <= 0) { + key->u.aes_cmac.replays++; + return RX_DROP_UNUSABLE; + } + + if (!(status->flag & RX_FLAG_DECRYPTED)) { + /* hardware didn't decrypt/verify MIC */ + bip_aad(skb, aad); + ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, + skb->data + 24, skb->len - 24, mic); + if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { + key->u.aes_cmac.icverrors++; + return RX_DROP_UNUSABLE; + } + } + + memcpy(key->u.aes_cmac.rx_pn, ipn, 6); + + /* Remove MMIE */ + skb_trim(skb, skb->len - sizeof(*mmie)); + + return RX_CONTINUE; +} + ieee80211_tx_result ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx) { diff --git a/net/mac80211/wpa.h b/net/mac80211/wpa.h index 43e109f27a89..06b7f167a176 100644 --- a/net/mac80211/wpa.h +++ b/net/mac80211/wpa.h @@ -32,8 +32,12 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx, ieee80211_tx_result ieee80211_crypto_aes_cmac_encrypt(struct ieee80211_tx_data *tx); +ieee80211_tx_result +ieee80211_crypto_aes_cmac_256_encrypt(struct ieee80211_tx_data *tx); ieee80211_rx_result ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx); +ieee80211_rx_result +ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx); ieee80211_tx_result ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx); ieee80211_rx_result -- 2.20.1