redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity
remarkable-linux/net/mac80211/tkip.c
Johannes Berg 8f20fc2498 [MAC80211]: embed key conf in key, fix driver interface 
This patch embeds the struct ieee80211_key_conf into struct ieee80211_key
and thus avoids allocations and having data present twice.

This required some more changes:
 1) The removal of the IEEE80211_KEY_DEFAULT_TX_KEY key flag.
    This flag isn't used by drivers nor should it be since
    we have a set_key_idx() callback. Maybe that callback needs
    to be extended to include the key conf, but only a driver that
    requires it will tell.
 2) The removal of the IEEE80211_KEY_DEFAULT_WEP_ONLY key flag.
    This flag is global, so it shouldn't be passed in the key
    conf structure. Pass it to the function instead.

Also, this patch removes the AID parameter to the set_key() callback
because it is currently unused and the hardware currently cannot know
about the AID anyway. I suspect this was used with some hardware that
actually selected the AID itself, but that functionality was removed.

Additionally, I've removed the ALG_NULL key algorithm since we have
ALG_NONE.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:51 -07:00

344 lines
9.9 KiB
C
Raw Blame History

/*
* Copyright 2002-2004, Instant802 Networks, Inc.
* Copyright 2005, Devicescape Software, 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/kernel.h>
#include <linux/types.h>
#include <linux/netdevice.h>
#include <net/mac80211.h>
#include "ieee80211_key.h"
#include "tkip.h"
#include "wep.h"
/* TKIP key mixing functions */
#define PHASE1_LOOP_COUNT 8
/* 2-byte by 2-byte subset of the full AES S-box table; second part of this
* table is identical to first part but byte-swapped */
static const u16 tkip_sbox[256] =
{
0xC6A5, 0xF884, 0xEE99, 0xF68D, 0xFF0D, 0xD6BD, 0xDEB1, 0x9154,
0x6050, 0x0203, 0xCEA9, 0x567D, 0xE719, 0xB562, 0x4DE6, 0xEC9A,
0x8F45, 0x1F9D, 0x8940, 0xFA87, 0xEF15, 0xB2EB, 0x8EC9, 0xFB0B,
0x41EC, 0xB367, 0x5FFD, 0x45EA, 0x23BF, 0x53F7, 0xE496, 0x9B5B,
0x75C2, 0xE11C, 0x3DAE, 0x4C6A, 0x6C5A, 0x7E41, 0xF502, 0x834F,
0x685C, 0x51F4, 0xD134, 0xF908, 0xE293, 0xAB73, 0x6253, 0x2A3F,
0x080C, 0x9552, 0x4665, 0x9D5E, 0x3028, 0x37A1, 0x0A0F, 0x2FB5,
0x0E09, 0x2436, 0x1B9B, 0xDF3D, 0xCD26, 0x4E69, 0x7FCD, 0xEA9F,
0x121B, 0x1D9E, 0x5874, 0x342E, 0x362D, 0xDCB2, 0xB4EE, 0x5BFB,
0xA4F6, 0x764D, 0xB761, 0x7DCE, 0x527B, 0xDD3E, 0x5E71, 0x1397,
0xA6F5, 0xB968, 0x0000, 0xC12C, 0x4060, 0xE31F, 0x79C8, 0xB6ED,
0xD4BE, 0x8D46, 0x67D9, 0x724B, 0x94DE, 0x98D4, 0xB0E8, 0x854A,
0xBB6B, 0xC52A, 0x4FE5, 0xED16, 0x86C5, 0x9AD7, 0x6655, 0x1194,
0x8ACF, 0xE910, 0x0406, 0xFE81, 0xA0F0, 0x7844, 0x25BA, 0x4BE3,
0xA2F3, 0x5DFE, 0x80C0, 0x058A, 0x3FAD, 0x21BC, 0x7048, 0xF104,
0x63DF, 0x77C1, 0xAF75, 0x4263, 0x2030, 0xE51A, 0xFD0E, 0xBF6D,
0x814C, 0x1814, 0x2635, 0xC32F, 0xBEE1, 0x35A2, 0x88CC, 0x2E39,
0x9357, 0x55F2, 0xFC82, 0x7A47, 0xC8AC, 0xBAE7, 0x322B, 0xE695,
0xC0A0, 0x1998, 0x9ED1, 0xA37F, 0x4466, 0x547E, 0x3BAB, 0x0B83,
0x8CCA, 0xC729, 0x6BD3, 0x283C, 0xA779, 0xBCE2, 0x161D, 0xAD76,
0xDB3B, 0x6456, 0x744E, 0x141E, 0x92DB, 0x0C0A, 0x486C, 0xB8E4,
0x9F5D, 0xBD6E, 0x43EF, 0xC4A6, 0x39A8, 0x31A4, 0xD337, 0xF28B,
0xD532, 0x8B43, 0x6E59, 0xDAB7, 0x018C, 0xB164, 0x9CD2, 0x49E0,
0xD8B4, 0xACFA, 0xF307, 0xCF25, 0xCAAF, 0xF48E, 0x47E9, 0x1018,
0x6FD5, 0xF088, 0x4A6F, 0x5C72, 0x3824, 0x57F1, 0x73C7, 0x9751,
0xCB23, 0xA17C, 0xE89C, 0x3E21, 0x96DD, 0x61DC, 0x0D86, 0x0F85,
0xE090, 0x7C42, 0x71C4, 0xCCAA, 0x90D8, 0x0605, 0xF701, 0x1C12,
0xC2A3, 0x6A5F, 0xAEF9, 0x69D0, 0x1791, 0x9958, 0x3A27, 0x27B9,
0xD938, 0xEB13, 0x2BB3, 0x2233, 0xD2BB, 0xA970, 0x0789, 0x33A7,
0x2DB6, 0x3C22, 0x1592, 0xC920, 0x8749, 0xAAFF, 0x5078, 0xA57A,
0x038F, 0x59F8, 0x0980, 0x1A17, 0x65DA, 0xD731, 0x84C6, 0xD0B8,
0x82C3, 0x29B0, 0x5A77, 0x1E11, 0x7BCB, 0xA8FC, 0x6DD6, 0x2C3A,
};
static inline u16 Mk16(u8 x, u8 y)
{
return ((u16) x << 8) | (u16) y;
}
static inline u8 Hi8(u16 v)
{
return v >> 8;
}
static inline u8 Lo8(u16 v)
{
return v & 0xff;
}
static inline u16 Hi16(u32 v)
{
return v >> 16;
}
static inline u16 Lo16(u32 v)
{
return v & 0xffff;
}
static inline u16 RotR1(u16 v)
{
return (v >> 1) | ((v & 0x0001) << 15);
}
static inline u16 tkip_S(u16 val)
{
u16 a = tkip_sbox[Hi8(val)];
return tkip_sbox[Lo8(val)] ^ Hi8(a) ^ (Lo8(a) << 8);
}
/* P1K := Phase1(TA, TK, TSC)
* TA = transmitter address (48 bits)
* TK = dot11DefaultKeyValue or dot11KeyMappingValue (128 bits)
* TSC = TKIP sequence counter (48 bits, only 32 msb bits used)
* P1K: 80 bits
*/
static void tkip_mixing_phase1(const u8 *ta, const u8 *tk, u32 tsc_IV32,
u16 *p1k)
{
int i, j;
p1k[0] = Lo16(tsc_IV32);
p1k[1] = Hi16(tsc_IV32);
p1k[2] = Mk16(ta[1], ta[0]);
p1k[3] = Mk16(ta[3], ta[2]);
p1k[4] = Mk16(ta[5], ta[4]);
for (i = 0; i < PHASE1_LOOP_COUNT; i++) {
j = 2 * (i & 1);
p1k[0] += tkip_S(p1k[4] ^ Mk16(tk[ 1 + j], tk[ 0 + j]));
p1k[1] += tkip_S(p1k[0] ^ Mk16(tk[ 5 + j], tk[ 4 + j]));
p1k[2] += tkip_S(p1k[1] ^ Mk16(tk[ 9 + j], tk[ 8 + j]));
p1k[3] += tkip_S(p1k[2] ^ Mk16(tk[13 + j], tk[12 + j]));
p1k[4] += tkip_S(p1k[3] ^ Mk16(tk[ 1 + j], tk[ 0 + j])) + i;
}
}
static void tkip_mixing_phase2(const u16 *p1k, const u8 *tk, u16 tsc_IV16,
u8 *rc4key)
{
u16 ppk[6];
int i;
ppk[0] = p1k[0];
ppk[1] = p1k[1];
ppk[2] = p1k[2];
ppk[3] = p1k[3];
ppk[4] = p1k[4];
ppk[5] = p1k[4] + tsc_IV16;
ppk[0] += tkip_S(ppk[5] ^ Mk16(tk[ 1], tk[ 0]));
ppk[1] += tkip_S(ppk[0] ^ Mk16(tk[ 3], tk[ 2]));
ppk[2] += tkip_S(ppk[1] ^ Mk16(tk[ 5], tk[ 4]));
ppk[3] += tkip_S(ppk[2] ^ Mk16(tk[ 7], tk[ 6]));
ppk[4] += tkip_S(ppk[3] ^ Mk16(tk[ 9], tk[ 8]));
ppk[5] += tkip_S(ppk[4] ^ Mk16(tk[11], tk[10]));
ppk[0] += RotR1(ppk[5] ^ Mk16(tk[13], tk[12]));
ppk[1] += RotR1(ppk[0] ^ Mk16(tk[15], tk[14]));
ppk[2] += RotR1(ppk[1]);
ppk[3] += RotR1(ppk[2]);
ppk[4] += RotR1(ppk[3]);
ppk[5] += RotR1(ppk[4]);
rc4key[0] = Hi8(tsc_IV16);
rc4key[1] = (Hi8(tsc_IV16) | 0x20) & 0x7f;
rc4key[2] = Lo8(tsc_IV16);
rc4key[3] = Lo8((ppk[5] ^ Mk16(tk[1], tk[0])) >> 1);
for (i = 0; i < 6; i++) {
rc4key[4 + 2 * i] = Lo8(ppk[i]);
rc4key[5 + 2 * i] = Hi8(ppk[i]);
}
}
/* Add TKIP IV and Ext. IV at @pos. @iv0, @iv1, and @iv2 are the first octets
* of the IV. Returns pointer to the octet following IVs (i.e., beginning of
* the packet payload). */
u8 * ieee80211_tkip_add_iv(u8 *pos, struct ieee80211_key *key,
u8 iv0, u8 iv1, u8 iv2)
{
*pos++ = iv0;
*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;
}
void ieee80211_tkip_gen_phase1key(struct ieee80211_key *key, u8 *ta,
u16 *phase1key)
{
tkip_mixing_phase1(ta, &key->conf.key[ALG_TKIP_TEMP_ENCR_KEY],
key->u.tkip.iv32, phase1key);
}
void ieee80211_tkip_gen_rc4key(struct ieee80211_key *key, u8 *ta,
u8 *rc4key)
{
/* Calculate per-packet key */
if (key->u.tkip.iv16 == 0 || !key->u.tkip.tx_initialized) {
/* IV16 wrapped around - perform TKIP phase 1 */
tkip_mixing_phase1(ta, &key->conf.key[ALG_TKIP_TEMP_ENCR_KEY],
key->u.tkip.iv32, key->u.tkip.p1k);
key->u.tkip.tx_initialized = 1;
}
tkip_mixing_phase2(key->u.tkip.p1k,
&key->conf.key[ALG_TKIP_TEMP_ENCR_KEY],
key->u.tkip.iv16, rc4key);
}
/* Encrypt packet payload with TKIP using @key. @pos is a pointer to the
* beginning of the buffer containing payload. This payload must include
* headroom of eight octets for IV and Ext. IV and taildroom of four octets
* for ICV. @payload_len is the length of payload (_not_ including extra
* headroom and tailroom). @ta is the transmitter addresses. */
void ieee80211_tkip_encrypt_data(struct crypto_blkcipher *tfm,
struct ieee80211_key *key,
u8 *pos, size_t payload_len, u8 *ta)
{
u8 rc4key[16];
ieee80211_tkip_gen_rc4key(key, ta, rc4key);
pos = ieee80211_tkip_add_iv(pos, key, rc4key[0], rc4key[1], rc4key[2]);
ieee80211_wep_encrypt_data(tfm, rc4key, 16, pos, payload_len);
}
/* Decrypt packet payload with TKIP using @key. @pos is a pointer to the
* beginning of the buffer containing IEEE 802.11 header payload, i.e.,
* including IV, Ext. IV, real data, Michael MIC, ICV. @payload_len is the
* length of payload, including IV, Ext. IV, MIC, ICV. */
int ieee80211_tkip_decrypt_data(struct crypto_blkcipher *tfm,
struct ieee80211_key *key,
u8 *payload, size_t payload_len, u8 *ta,
int only_iv, int queue)
{
u32 iv32;
u32 iv16;
u8 rc4key[16], keyid, *pos = payload;
int res;
if (payload_len < 12)
return -1;
iv16 = (pos[0] << 8) | pos[2];
keyid = pos[3];
iv32 = pos[4] | (pos[5] << 8) | (pos[6] << 16) | (pos[7] << 24);
pos += 8;
#ifdef CONFIG_TKIP_DEBUG
{
int i;
printk(KERN_DEBUG "TKIP decrypt: data(len=%zd)", payload_len);
for (i = 0; i < payload_len; i++)
printk(" %02x", payload[i]);
printk("\n");
printk(KERN_DEBUG "TKIP decrypt: iv16=%04x iv32=%08x\n",
iv16, iv32);
}
#endif /* CONFIG_TKIP_DEBUG */
if (!(keyid & (1 << 5)))
return TKIP_DECRYPT_NO_EXT_IV;
if ((keyid >> 6) != key->conf.keyidx)
return TKIP_DECRYPT_INVALID_KEYIDX;
if (key->u.tkip.rx_initialized[queue] &&
(iv32 < key->u.tkip.iv32_rx[queue] ||
(iv32 == key->u.tkip.iv32_rx[queue] &&
iv16 <= key->u.tkip.iv16_rx[queue]))) {
#ifdef CONFIG_TKIP_DEBUG
printk(KERN_DEBUG "TKIP replay detected for RX frame from "
MAC_FMT " (RX IV (%04x,%02x) <= prev. IV (%04x,%02x)\n",
MAC_ARG(ta),
iv32, iv16, key->u.tkip.iv32_rx[queue],
key->u.tkip.iv16_rx[queue]);
#endif /* CONFIG_TKIP_DEBUG */
return TKIP_DECRYPT_REPLAY;
}
if (only_iv) {
res = TKIP_DECRYPT_OK;
key->u.tkip.rx_initialized[queue] = 1;
goto done;
}
if (!key->u.tkip.rx_initialized[queue] ||
key->u.tkip.iv32_rx[queue] != iv32) {
key->u.tkip.rx_initialized[queue] = 1;
/* IV16 wrapped around - perform TKIP phase 1 */
tkip_mixing_phase1(ta, &key->conf.key[ALG_TKIP_TEMP_ENCR_KEY],
iv32, key->u.tkip.p1k_rx[queue]);
#ifdef CONFIG_TKIP_DEBUG
{
int i;
printk(KERN_DEBUG "TKIP decrypt: Phase1 TA=" MAC_FMT
" TK=", MAC_ARG(ta));
for (i = 0; i < 16; i++)
printk("%02x ",
key->conf.key[
ALG_TKIP_TEMP_ENCR_KEY + i]);
printk("\n");
printk(KERN_DEBUG "TKIP decrypt: P1K=");
for (i = 0; i < 5; i++)
printk("%04x ", key->u.tkip.p1k_rx[queue][i]);
printk("\n");
}
#endif /* CONFIG_TKIP_DEBUG */
}
tkip_mixing_phase2(key->u.tkip.p1k_rx[queue],
&key->conf.key[ALG_TKIP_TEMP_ENCR_KEY],
iv16, rc4key);
#ifdef CONFIG_TKIP_DEBUG
{
int i;
printk(KERN_DEBUG "TKIP decrypt: Phase2 rc4key=");
for (i = 0; i < 16; i++)
printk("%02x ", rc4key[i]);
printk("\n");
}
#endif /* CONFIG_TKIP_DEBUG */
res = ieee80211_wep_decrypt_data(tfm, rc4key, 16, pos, payload_len - 12);
done:
if (res == TKIP_DECRYPT_OK) {
/* FIX: these should be updated only after Michael MIC has been
* verified */
/* Record previously received IV */
key->u.tkip.iv32_rx[queue] = iv32;
key->u.tkip.iv16_rx[queue] = iv16;
}
return res;
}
View git blame Copy permalink