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authorJouni Malinen <jouni@qca.qualcomm.com>2015-01-24 20:52:06 +0300
committerJohannes Berg <johannes.berg@intel.com>2015-01-27 13:06:09 +0300
commit00b9cfa3ff38401bd70c34b250ca13e5ea347b4a (patch)
tree1c3564bf28a6f4b49140a5e023520a1dc658d5c6 /net/mac80211/wpa.c
parentcfcf1682c4ca8f601a4702255958e0b1c9aa12cc (diff)
downloadlinux-00b9cfa3ff38401bd70c34b250ca13e5ea347b4a.tar.xz
mac80111: Add GCMP and GCMP-256 ciphers
This allows mac80211 to configure GCMP and GCMP-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 <jouni@qca.qualcomm.com> [remove a spurious newline] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/mac80211/wpa.c')
-rw-r--r--net/mac80211/wpa.c224
1 files changed, 224 insertions, 0 deletions
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 12398fde02e8..96b65c240109 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -22,6 +22,7 @@
#include "tkip.h"
#include "aes_ccm.h"
#include "aes_cmac.h"
+#include "aes_gcm.h"
#include "wpa.h"
ieee80211_tx_result
@@ -546,6 +547,229 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx)
return RX_CONTINUE;
}
+static void gcmp_special_blocks(struct sk_buff *skb, u8 *pn, u8 *j_0, u8 *aad)
+{
+ __le16 mask_fc;
+ u8 qos_tid;
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+
+ memcpy(j_0, hdr->addr2, ETH_ALEN);
+ memcpy(&j_0[ETH_ALEN], pn, IEEE80211_GCMP_PN_LEN);
+ j_0[13] = 0;
+ j_0[14] = 0;
+ j_0[AES_BLOCK_SIZE - 1] = 0x01;
+
+ /* AAD (extra authenticate-only data) / masked 802.11 header
+ * FC | A1 | A2 | A3 | SC | [A4] | [QC]
+ */
+ put_unaligned_be16(ieee80211_hdrlen(hdr->frame_control) - 2, &aad[0]);
+ /* Mask FC: zero subtype b4 b5 b6 (if not mgmt)
+ * Retry, PwrMgt, MoreData; set Protected
+ */
+ mask_fc = hdr->frame_control;
+ mask_fc &= ~cpu_to_le16(IEEE80211_FCTL_RETRY |
+ IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
+ if (!ieee80211_is_mgmt(hdr->frame_control))
+ mask_fc &= ~cpu_to_le16(0x0070);
+ mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
+
+ put_unaligned(mask_fc, (__le16 *)&aad[2]);
+ memcpy(&aad[4], &hdr->addr1, 3 * ETH_ALEN);
+
+ /* Mask Seq#, leave Frag# */
+ aad[22] = *((u8 *)&hdr->seq_ctrl) & 0x0f;
+ aad[23] = 0;
+
+ if (ieee80211_is_data_qos(hdr->frame_control))
+ qos_tid = *ieee80211_get_qos_ctl(hdr) &
+ IEEE80211_QOS_CTL_TID_MASK;
+ else
+ qos_tid = 0;
+
+ if (ieee80211_has_a4(hdr->frame_control)) {
+ memcpy(&aad[24], hdr->addr4, ETH_ALEN);
+ aad[30] = qos_tid;
+ aad[31] = 0;
+ } else {
+ memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
+ aad[24] = qos_tid;
+ }
+}
+
+static inline void gcmp_pn2hdr(u8 *hdr, const 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 void gcmp_hdr2pn(u8 *pn, const 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];
+}
+
+static int gcmp_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;
+ u8 pn[6];
+ u64 pn64;
+ u8 aad[2 * AES_BLOCK_SIZE];
+ u8 j_0[AES_BLOCK_SIZE];
+
+ if (info->control.hw_key &&
+ !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_GENERATE_IV) &&
+ !(info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
+ !((info->control.hw_key->flags &
+ IEEE80211_KEY_FLAG_GENERATE_IV_MGMT) &&
+ ieee80211_is_mgmt(hdr->frame_control))) {
+ /* hwaccel has no need for preallocated room for GCMP
+ * header or MIC fields
+ */
+ return 0;
+ }
+
+ hdrlen = ieee80211_hdrlen(hdr->frame_control);
+ len = skb->len - hdrlen;
+
+ if (info->control.hw_key)
+ tail = 0;
+ else
+ tail = IEEE80211_GCMP_MIC_LEN;
+
+ if (WARN_ON(skb_tailroom(skb) < tail ||
+ skb_headroom(skb) < IEEE80211_GCMP_HDR_LEN))
+ return -1;
+
+ pos = skb_push(skb, IEEE80211_GCMP_HDR_LEN);
+ memmove(pos, pos + IEEE80211_GCMP_HDR_LEN, hdrlen);
+ skb_set_network_header(skb, skb_network_offset(skb) +
+ IEEE80211_GCMP_HDR_LEN);
+
+ /* the HW only needs room for the IV, but not the actual IV */
+ if (info->control.hw_key &&
+ (info->control.hw_key->flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE))
+ return 0;
+
+ hdr = (struct ieee80211_hdr *)pos;
+ pos += hdrlen;
+
+ pn64 = atomic64_inc_return(&key->u.gcmp.tx_pn);
+
+ pn[5] = pn64;
+ pn[4] = pn64 >> 8;
+ pn[3] = pn64 >> 16;
+ pn[2] = pn64 >> 24;
+ pn[1] = pn64 >> 32;
+ pn[0] = pn64 >> 40;
+
+ gcmp_pn2hdr(pos, pn, key->conf.keyidx);
+
+ /* hwaccel - with software GCMP header */
+ if (info->control.hw_key)
+ return 0;
+
+ pos += IEEE80211_GCMP_HDR_LEN;
+ gcmp_special_blocks(skb, pn, j_0, aad);
+ ieee80211_aes_gcm_encrypt(key->u.gcmp.tfm, j_0, aad, pos, len,
+ skb_put(skb, IEEE80211_GCMP_MIC_LEN));
+
+ return 0;
+}
+
+ieee80211_tx_result
+ieee80211_crypto_gcmp_encrypt(struct ieee80211_tx_data *tx)
+{
+ struct sk_buff *skb;
+
+ ieee80211_tx_set_protected(tx);
+
+ skb_queue_walk(&tx->skbs, skb) {
+ if (gcmp_encrypt_skb(tx, skb) < 0)
+ return TX_DROP;
+ }
+
+ return TX_CONTINUE;
+}
+
+ieee80211_rx_result
+ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
+{
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
+ int hdrlen;
+ struct ieee80211_key *key = rx->key;
+ struct sk_buff *skb = rx->skb;
+ struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
+ u8 pn[IEEE80211_GCMP_PN_LEN];
+ int data_len;
+ int queue;
+
+ hdrlen = ieee80211_hdrlen(hdr->frame_control);
+
+ if (!ieee80211_is_data(hdr->frame_control) &&
+ !ieee80211_is_robust_mgmt_frame(skb))
+ return RX_CONTINUE;
+
+ data_len = skb->len - hdrlen - IEEE80211_GCMP_HDR_LEN -
+ IEEE80211_GCMP_MIC_LEN;
+ if (!rx->sta || data_len < 0)
+ return RX_DROP_UNUSABLE;
+
+ if (status->flag & RX_FLAG_DECRYPTED) {
+ if (!pskb_may_pull(rx->skb, hdrlen + IEEE80211_GCMP_HDR_LEN))
+ return RX_DROP_UNUSABLE;
+ } else {
+ if (skb_linearize(rx->skb))
+ return RX_DROP_UNUSABLE;
+ }
+
+ gcmp_hdr2pn(pn, skb->data + hdrlen);
+
+ queue = rx->security_idx;
+
+ if (memcmp(pn, key->u.gcmp.rx_pn[queue], IEEE80211_GCMP_PN_LEN) <= 0) {
+ key->u.gcmp.replays++;
+ return RX_DROP_UNUSABLE;
+ }
+
+ if (!(status->flag & RX_FLAG_DECRYPTED)) {
+ u8 aad[2 * AES_BLOCK_SIZE];
+ u8 j_0[AES_BLOCK_SIZE];
+ /* hardware didn't decrypt/verify MIC */
+ gcmp_special_blocks(skb, pn, j_0, aad);
+
+ if (ieee80211_aes_gcm_decrypt(
+ key->u.gcmp.tfm, j_0, aad,
+ skb->data + hdrlen + IEEE80211_GCMP_HDR_LEN,
+ data_len,
+ skb->data + skb->len - IEEE80211_GCMP_MIC_LEN))
+ return RX_DROP_UNUSABLE;
+ }
+
+ memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
+
+ /* Remove GCMP header and MIC */
+ if (pskb_trim(skb, skb->len - IEEE80211_GCMP_MIC_LEN))
+ return RX_DROP_UNUSABLE;
+ memmove(skb->data + IEEE80211_GCMP_HDR_LEN, skb->data, hdrlen);
+ skb_pull(skb, IEEE80211_GCMP_HDR_LEN);
+
+ return RX_CONTINUE;
+}
+
static ieee80211_tx_result
ieee80211_crypto_cs_encrypt(struct ieee80211_tx_data *tx,
struct sk_buff *skb)