Re: [PATCH-mm 1/3] mac80211: tkip.c use get/put_unaligned helpers

From: Jiri Benc
Date: Thu Apr 17 2008 - 04:59:48 EST


On Wed, 16 Apr 2008 11:29:30 -0700, Harvey Harrison wrote:
> Signed-off-by: Harvey Harrison <harvey.harrison@xxxxxxxxx>
> ---
> This depends on the introduction of the new unaligned helpers, and applies
> on top of the cleanup patches already in -mm.

Please send all mac80211 patches to the linux-wireless mailing list and
CC Johannes Berg. (It's a good idea to resend all of the mac80211
patches you sent.)

Thanks,

Jiri

>
> net/mac80211/tkip.c | 62 +++++++++++++++++++--------------------------------
> 1 files changed, 23 insertions(+), 39 deletions(-)
>
> diff --git a/net/mac80211/tkip.c b/net/mac80211/tkip.c
> index 61c60d3..1c5a46a 100644
> --- a/net/mac80211/tkip.c
> +++ b/net/mac80211/tkip.c
> @@ -63,16 +63,6 @@ static const u16 tkip_sbox[256] =
> 0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A,
> };
>
> -
> -/*
> - * Get a cpu-byteorder u16 from a u8 pointer fixing up possible unaligned
> - * accesses.
> - */
> -static inline u16 getle16(const u8 *x)
> -{
> - return le16_to_cpu(get_unaligned((__le16 *)x));
> -}
> -
> static inline u16 tkip_S(u16 val)
> {
> return tkip_sbox[val & 0xff] ^ swab16(tkip_sbox[val >> 8]);
> @@ -91,17 +81,17 @@ static void tkip_mixing_phase1(const u8 *ta, const u8 *tk, u32 tsc_IV32,
>
> p1k[0] = tsc_IV32 & 0xFFFF;
> p1k[1] = tsc_IV32 >> 16;
> - p1k[2] = getle16(ta + 0);
> - p1k[3] = getle16(ta + 2);
> - p1k[4] = getle16(ta + 4);
> + p1k[2] = get_unaligned_le16(ta + 0);
> + p1k[3] = get_unaligned_le16(ta + 2);
> + p1k[4] = get_unaligned_le16(ta + 4);
>
> for (i = 0; i < PHASE1_LOOP_COUNT; i++) {
> j = 2 * (i & 1);
> - p1k[0] += tkip_S(p1k[4] ^ getle16(tk + 0 + j));
> - p1k[1] += tkip_S(p1k[0] ^ getle16(tk + 4 + j));
> - p1k[2] += tkip_S(p1k[1] ^ getle16(tk + 8 + j));
> - p1k[3] += tkip_S(p1k[2] ^ getle16(tk + 12 + j));
> - p1k[4] += tkip_S(p1k[3] ^ getle16(tk + 0 + j)) + i;
> + p1k[0] += tkip_S(p1k[4] ^ get_unaligned_le16(tk + 0 + j));
> + p1k[1] += tkip_S(p1k[0] ^ get_unaligned_le16(tk + 4 + j));
> + p1k[2] += tkip_S(p1k[1] ^ get_unaligned_le16(tk + 8 + j));
> + p1k[3] += tkip_S(p1k[2] ^ get_unaligned_le16(tk + 12 + j));
> + p1k[4] += tkip_S(p1k[3] ^ get_unaligned_le16(tk + 0 + j)) + i;
> }
> }
>
> @@ -119,14 +109,14 @@ static void tkip_mixing_phase2(const u16 *p1k, const u8 *tk, u16 tsc_IV16,
> ppk[4] = p1k[4];
> ppk[5] = p1k[4] + tsc_IV16;
>
> - ppk[0] += tkip_S(ppk[5] ^ getle16(tk + 0));
> - ppk[1] += tkip_S(ppk[0] ^ getle16(tk + 2));
> - ppk[2] += tkip_S(ppk[1] ^ getle16(tk + 4));
> - ppk[3] += tkip_S(ppk[2] ^ getle16(tk + 6));
> - ppk[4] += tkip_S(ppk[3] ^ getle16(tk + 8));
> - ppk[5] += tkip_S(ppk[4] ^ getle16(tk + 10));
> - ppk[0] += ror16(ppk[5] ^ getle16(tk + 12), 1);
> - ppk[1] += ror16(ppk[0] ^ getle16(tk + 14), 1);
> + ppk[0] += tkip_S(ppk[5] ^ get_unaligned_le16(tk + 0));
> + ppk[1] += tkip_S(ppk[0] ^ get_unaligned_le16(tk + 2));
> + ppk[2] += tkip_S(ppk[1] ^ get_unaligned_le16(tk + 4));
> + ppk[3] += tkip_S(ppk[2] ^ get_unaligned_le16(tk + 6));
> + ppk[4] += tkip_S(ppk[3] ^ get_unaligned_le16(tk + 8));
> + ppk[5] += tkip_S(ppk[4] ^ get_unaligned_le16(tk + 10));
> + ppk[0] += ror16(ppk[5] ^ get_unaligned_le16(tk + 12), 1);
> + ppk[1] += ror16(ppk[0] ^ get_unaligned_le16(tk + 14), 1);
> ppk[2] += ror16(ppk[1], 1);
> ppk[3] += ror16(ppk[2], 1);
> ppk[4] += ror16(ppk[3], 1);
> @@ -135,11 +125,11 @@ static void tkip_mixing_phase2(const u16 *p1k, const u8 *tk, u16 tsc_IV16,
> rc4key[0] = tsc_IV16 >> 8;
> rc4key[1] = ((tsc_IV16 >> 8) | 0x20) & 0x7f;
> rc4key[2] = tsc_IV16 & 0xFF;
> - rc4key[3] = ((ppk[5] ^ getle16(tk)) >> 1) & 0xFF;
> + rc4key[3] = ((ppk[5] ^ get_unaligned_le16(tk)) >> 1) & 0xFF;
>
> rc4key += 4;
> - for (i = 0; i < 6; i++)
> - put_unaligned(cpu_to_le16(ppk[i]), (__le16 *)rc4key + i);
> + for (i = 0; i < 12; i += 2)
> + put_unaligned_le16(ppk[i], rc4key + i);
> }
>
>
> @@ -153,11 +143,8 @@ u8 * ieee80211_tkip_add_iv(u8 *pos, struct ieee80211_key *key,
> *pos++ = iv1;
> *pos++ = iv2;
> *pos++ = (key->conf.keyidx << 6) | (1 << 5) /* Ext IV */;
> - *pos++ = key->u.tkip.iv32 & 0xff;
> - *pos++ = (key->u.tkip.iv32 >> 8) & 0xff;
> - *pos++ = (key->u.tkip.iv32 >> 16) & 0xff;
> - *pos++ = (key->u.tkip.iv32 >> 24) & 0xff;
> - return pos;
> + put_unaligned_le32(key->u.tkip.iv32, pos);
> + return pos + 4;
> }
>
>
> @@ -200,10 +187,7 @@ void ieee80211_get_tkip_key(struct ieee80211_key_conf *keyconf,
>
> iv16 = data[hdr_len] << 8;
> iv16 += data[hdr_len + 2];
> - iv32 = data[hdr_len + 4] +
> - (data[hdr_len + 5] >> 8) +
> - (data[hdr_len + 6] >> 16) +
> - (data[hdr_len + 7] >> 24);
> + iv32 = get_unaligned_le32(data + hdr_len + 4);
>
> #ifdef CONFIG_TKIP_DEBUG
> printk(KERN_DEBUG "TKIP encrypt: iv16 = 0x%04x, iv32 = 0x%08x\n",
> @@ -274,7 +258,7 @@ int ieee80211_tkip_decrypt_data(struct crypto_blkcipher *tfm,
>
> iv16 = (pos[0] << 8) | pos[2];
> keyid = pos[3];
> - iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24);
> + iv32 = get_unaligned_le32(pos + 4);
> pos += 8;
> #ifdef CONFIG_TKIP_DEBUG
> {
> --
> 1.5.5.144.g3e42
>


--
Jiri Benc
SUSE Labs
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