Commit f14df804 authored by Harvey Harrison's avatar Harvey Harrison Committed by John W. Linville
Browse files

mac80211: remove one user of ieee80211_get_hdr_info



ccmp_special_blocks was only using it to calculate data_len,
calculate that directly.

Use unaligned helpers rather than masking/shifting.

Use symbolic constants for the masked frame_control, and do it directly
on a le16 value.
Signed-off-by: default avatarHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 73e1f7c8
......@@ -11,6 +11,8 @@
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/compiler.h>
#include <linux/ieee80211.h>
#include <asm/unaligned.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
......@@ -296,67 +298,61 @@ ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
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;
__le16 mask_fc;
int a4_included;
u8 qos_tid;
u16 data_len, len_a;
unsigned int hdrlen;
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 &= IEEE80211_QOS_CTL_TID_MASK;
} else
qos_included = 0;
/* First block, b_0 */
/*
* Mask FC: zero subtype b4 b5 b6
* Retry, PwrMgt, MoreData; set Protected
*/
mask_fc = hdr->frame_control;
mask_fc &= ~cpu_to_le16(0x0070 | IEEE80211_FCTL_RETRY |
IEEE80211_FCTL_PM | IEEE80211_FCTL_MOREDATA);
mask_fc |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
hdrlen = ieee80211_hdrlen(hdr->frame_control);
len_a = hdrlen - 2;
a4_included = ieee80211_has_a4(hdr->frame_control);
if (ieee80211_is_data_qos(hdr->frame_control))
qos_tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
else
qos_tid = 0;
data_len = skb->len - hdrlen - CCMP_HDR_LEN;
if (encrypted)
data_len -= CCMP_MIC_LEN;
/* 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, ETH_ALEN);
memcpy(&b_0[8], pn, CCMP_PN_LEN);
/* l(m) */
b_0[14] = (data_len >> 8) & 0xff;
b_0[15] = data_len & 0xff;
put_unaligned_be16(data_len, &b_0[14]);
/* 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 += IEEE80211_QOS_CTL_LEN;
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);
put_unaligned_be16(len_a, &aad[0]);
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 (a4_included) {
memcpy(&aad[24], hdr->addr4, ETH_ALEN);
aad[30] = 0;
aad[30] = qos_tid;
aad[31] = 0;
} else
} else {
memset(&aad[24], 0, ETH_ALEN + IEEE80211_QOS_CTL_LEN);
if (qos_included) {
u8 *dpos = &aad[a4_included ? 30 : 24];
/* Mask QoS Control field */
dpos[0] = qos_tid;
dpos[1] = 0;
aad[24] = qos_tid;
}
}
......
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