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rtw_security.c
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rtw_security.c
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/******************************************************************************
*
* Copyright(c) 2007 - 2017 Realtek Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
*****************************************************************************/
#define _RTW_SECURITY_C_
#include <drv_types.h>
static const char *_security_type_str[] = {
"N/A",
"WEP40",
"TKIP",
"TKIP_WM",
"AES",
"WEP104",
"SMS4",
"WEP_WPA",
"BIP",
};
const char *security_type_str(u8 value)
{
#ifdef CONFIG_IEEE80211W
if (value <= _BIP_)
#else
if (value <= _WEP_WPA_MIXED_)
#endif
return _security_type_str[value];
return NULL;
}
#ifdef DBG_SW_SEC_CNT
#define WEP_SW_ENC_CNT_INC(sec, ra) do {\
if (is_broadcast_mac_addr(ra)) \
sec->wep_sw_enc_cnt_bc++; \
else if (is_multicast_mac_addr(ra)) \
sec->wep_sw_enc_cnt_mc++; \
else \
sec->wep_sw_enc_cnt_uc++; \
} while (0)
#define WEP_SW_DEC_CNT_INC(sec, ra) do {\
if (is_broadcast_mac_addr(ra)) \
sec->wep_sw_dec_cnt_bc++; \
else if (is_multicast_mac_addr(ra)) \
sec->wep_sw_dec_cnt_mc++; \
else \
sec->wep_sw_dec_cnt_uc++; \
} while (0)
#define TKIP_SW_ENC_CNT_INC(sec, ra) do {\
if (is_broadcast_mac_addr(ra)) \
sec->tkip_sw_enc_cnt_bc++; \
else if (is_multicast_mac_addr(ra)) \
sec->tkip_sw_enc_cnt_mc++; \
else \
sec->tkip_sw_enc_cnt_uc++; \
} while (0)
#define TKIP_SW_DEC_CNT_INC(sec, ra) do {\
if (is_broadcast_mac_addr(ra)) \
sec->tkip_sw_dec_cnt_bc++; \
else if (is_multicast_mac_addr(ra)) \
sec->tkip_sw_dec_cnt_mc++; \
else \
sec->tkip_sw_dec_cnt_uc++; \
} while (0)
#define AES_SW_ENC_CNT_INC(sec, ra) do {\
if (is_broadcast_mac_addr(ra)) \
sec->aes_sw_enc_cnt_bc++; \
else if (is_multicast_mac_addr(ra)) \
sec->aes_sw_enc_cnt_mc++; \
else \
sec->aes_sw_enc_cnt_uc++; \
} while (0)
#define AES_SW_DEC_CNT_INC(sec, ra) do {\
if (is_broadcast_mac_addr(ra)) \
sec->aes_sw_dec_cnt_bc++; \
else if (is_multicast_mac_addr(ra)) \
sec->aes_sw_dec_cnt_mc++; \
else \
sec->aes_sw_dec_cnt_uc++; \
} while (0)
#else
#define WEP_SW_ENC_CNT_INC(sec, ra)
#define WEP_SW_DEC_CNT_INC(sec, ra)
#define TKIP_SW_ENC_CNT_INC(sec, ra)
#define TKIP_SW_DEC_CNT_INC(sec, ra)
#define AES_SW_ENC_CNT_INC(sec, ra)
#define AES_SW_DEC_CNT_INC(sec, ra)
#endif /* DBG_SW_SEC_CNT */
/* *****WEP related***** */
#define CRC32_POLY 0x04c11db7
struct arc4context {
u32 x;
u32 y;
u8 state[256];
};
static void arcfour_init(struct arc4context *parc4ctx, u8 *key, u32 key_len)
{
u32 t, u;
u32 keyindex;
u32 stateindex;
u8 *state;
u32 counter;
state = parc4ctx->state;
parc4ctx->x = 0;
parc4ctx->y = 0;
for (counter = 0; counter < 256; counter++)
state[counter] = (u8)counter;
keyindex = 0;
stateindex = 0;
for (counter = 0; counter < 256; counter++) {
t = state[counter];
stateindex = (stateindex + key[keyindex] + t) & 0xff;
u = state[stateindex];
state[stateindex] = (u8)t;
state[counter] = (u8)u;
if (++keyindex >= key_len)
keyindex = 0;
}
}
static u32 arcfour_byte(struct arc4context *parc4ctx)
{
u32 x;
u32 y;
u32 sx, sy;
u8 *state;
state = parc4ctx->state;
x = (parc4ctx->x + 1) & 0xff;
sx = state[x];
y = (sx + parc4ctx->y) & 0xff;
sy = state[y];
parc4ctx->x = x;
parc4ctx->y = y;
state[y] = (u8)sx;
state[x] = (u8)sy;
return state[(sx + sy) & 0xff];
}
static void arcfour_encrypt(struct arc4context *parc4ctx,
u8 *dest,
u8 *src,
u32 len)
{
u32 i;
for (i = 0; i < len; i++)
dest[i] = src[i] ^ (unsigned char)arcfour_byte(parc4ctx);
}
static sint bcrc32initialized = 0;
static u32 crc32_table[256];
static u8 crc32_reverseBit(u8 data)
{
return (u8)((data << 7) & 0x80) | ((data << 5) & 0x40) | ((data << 3) & 0x20) | ((data << 1) & 0x10) | ((data >> 1) & 0x08) | ((data >> 3) & 0x04) | ((data >> 5) & 0x02) | ((
data >> 7) & 0x01) ;
}
static void crc32_init(void)
{
if (bcrc32initialized == 1)
goto exit;
else {
sint i, j;
u32 c;
u8 *p = (u8 *)&c, *p1;
u8 k;
c = 0x12340000;
for (i = 0; i < 256; ++i) {
k = crc32_reverseBit((u8)i);
for (c = ((u32)k) << 24, j = 8; j > 0; --j)
c = c & 0x80000000 ? (c << 1) ^ CRC32_POLY : (c << 1);
p1 = (u8 *)&crc32_table[i];
p1[0] = crc32_reverseBit(p[3]);
p1[1] = crc32_reverseBit(p[2]);
p1[2] = crc32_reverseBit(p[1]);
p1[3] = crc32_reverseBit(p[0]);
}
bcrc32initialized = 1;
}
exit:
return;
}
static u32 getcrc32(u8 *buf, sint len)
{
u8 *p;
u32 crc;
if (bcrc32initialized == 0)
crc32_init();
crc = 0xffffffff; /* preload shift register, per CRC-32 spec */
for (p = buf; len > 0; ++p, --len)
crc = crc32_table[(crc ^ *p) & 0xff] ^ (crc >> 8);
return ~crc; /* transmit complement, per CRC-32 spec */
}
/*
Need to consider the fragment situation
*/
void rtw_wep_encrypt(_adapter *padapter, u8 *pxmitframe)
{
/* exclude ICV */
unsigned char crc[4];
struct arc4context mycontext;
sint curfragnum, length;
u32 keylength;
u8 *pframe, *payload, *iv; /* ,*wepkey */
u8 wepkey[16];
u8 hw_hdr_offset = 0;
struct pkt_attrib *pattrib = &((struct xmit_frame *)pxmitframe)->attrib;
struct security_priv *psecuritypriv = &padapter->securitypriv;
struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
if (((struct xmit_frame *)pxmitframe)->buf_addr == NULL)
return;
#ifdef CONFIG_USB_TX_AGGREGATION
hw_hdr_offset = TXDESC_SIZE +
(((struct xmit_frame *)pxmitframe)->pkt_offset * PACKET_OFFSET_SZ);
#else
#ifdef CONFIG_TX_EARLY_MODE
hw_hdr_offset = TXDESC_OFFSET + EARLY_MODE_INFO_SIZE;
#else
hw_hdr_offset = TXDESC_OFFSET;
#endif
#endif
pframe = ((struct xmit_frame *)pxmitframe)->buf_addr + hw_hdr_offset;
/* start to encrypt each fragment */
if ((pattrib->encrypt == _WEP40_) || (pattrib->encrypt == _WEP104_)) {
keylength = psecuritypriv->dot11DefKeylen[psecuritypriv->dot11PrivacyKeyIndex];
for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
iv = pframe + pattrib->hdrlen;
_rtw_memcpy(&wepkey[0], iv, 3);
_rtw_memcpy(&wepkey[3], &psecuritypriv->dot11DefKey[psecuritypriv->dot11PrivacyKeyIndex].skey[0], keylength);
payload = pframe + pattrib->iv_len + pattrib->hdrlen;
if ((curfragnum + 1) == pattrib->nr_frags) {
/* the last fragment */
length = pattrib->last_txcmdsz - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
*((u32 *)crc) = cpu_to_le32(getcrc32(payload, length));
arcfour_init(&mycontext, wepkey, 3 + keylength);
arcfour_encrypt(&mycontext, payload, payload, length);
arcfour_encrypt(&mycontext, payload + length, crc, 4);
} else {
length = pxmitpriv->frag_len - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len ;
*((u32 *)crc) = cpu_to_le32(getcrc32(payload, length));
arcfour_init(&mycontext, wepkey, 3 + keylength);
arcfour_encrypt(&mycontext, payload, payload, length);
arcfour_encrypt(&mycontext, payload + length, crc, 4);
pframe += pxmitpriv->frag_len;
pframe = (u8 *)RND4((SIZE_PTR)(pframe));
}
}
WEP_SW_ENC_CNT_INC(psecuritypriv, pattrib->ra);
}
}
void rtw_wep_decrypt(_adapter *padapter, u8 *precvframe)
{
/* exclude ICV */
u8 crc[4];
struct arc4context mycontext;
sint length;
u32 keylength;
u8 *pframe, *payload, *iv, wepkey[16];
u8 keyindex;
struct rx_pkt_attrib *prxattrib = &(((union recv_frame *)precvframe)->u.hdr.attrib);
struct security_priv *psecuritypriv = &padapter->securitypriv;
pframe = (unsigned char *)((union recv_frame *)precvframe)->u.hdr.rx_data;
/* start to decrypt recvframe */
if ((prxattrib->encrypt == _WEP40_) || (prxattrib->encrypt == _WEP104_)) {
iv = pframe + prxattrib->hdrlen;
/* keyindex=(iv[3]&0x3); */
keyindex = prxattrib->key_index;
keylength = psecuritypriv->dot11DefKeylen[keyindex];
_rtw_memcpy(&wepkey[0], iv, 3);
/* _rtw_memcpy(&wepkey[3], &psecuritypriv->dot11DefKey[psecuritypriv->dot11PrivacyKeyIndex].skey[0],keylength); */
_rtw_memcpy(&wepkey[3], &psecuritypriv->dot11DefKey[keyindex].skey[0], keylength);
length = ((union recv_frame *)precvframe)->u.hdr.len - prxattrib->hdrlen - prxattrib->iv_len;
payload = pframe + prxattrib->iv_len + prxattrib->hdrlen;
/* decrypt payload include icv */
arcfour_init(&mycontext, wepkey, 3 + keylength);
arcfour_encrypt(&mycontext, payload, payload, length);
/* calculate icv and compare the icv */
*((u32 *)crc) = le32_to_cpu(getcrc32(payload, length - 4));
WEP_SW_DEC_CNT_INC(psecuritypriv, prxattrib->ra);
}
return;
}
/* 3 =====TKIP related===== */
static u32 secmicgetuint32(u8 *p)
/* Convert from Byte[] to Us4Byte32 in a portable way */
{
s32 i;
u32 res = 0;
for (i = 0; i < 4; i++)
res |= ((u32)(*p++)) << (8 * i);
return res;
}
static void secmicputuint32(u8 *p, u32 val)
/* Convert from Us4Byte32 to Byte[] in a portable way */
{
long i;
for (i = 0; i < 4; i++) {
*p++ = (u8)(val & 0xff);
val >>= 8;
}
}
static void secmicclear(struct mic_data *pmicdata)
{
/* Reset the state to the empty message. */
pmicdata->L = pmicdata->K0;
pmicdata->R = pmicdata->K1;
pmicdata->nBytesInM = 0;
pmicdata->M = 0;
}
void rtw_secmicsetkey(struct mic_data *pmicdata, u8 *key)
{
/* Set the key */
pmicdata->K0 = secmicgetuint32(key);
pmicdata->K1 = secmicgetuint32(key + 4);
/* and reset the message */
secmicclear(pmicdata);
}
void rtw_secmicappendbyte(struct mic_data *pmicdata, u8 b)
{
/* Append the byte to our word-sized buffer */
pmicdata->M |= ((unsigned long)b) << (8 * pmicdata->nBytesInM);
pmicdata->nBytesInM++;
/* Process the word if it is full. */
if (pmicdata->nBytesInM >= 4) {
pmicdata->L ^= pmicdata->M;
pmicdata->R ^= ROL32(pmicdata->L, 17);
pmicdata->L += pmicdata->R;
pmicdata->R ^= ((pmicdata->L & 0xff00ff00) >> 8) | ((pmicdata->L & 0x00ff00ff) << 8);
pmicdata->L += pmicdata->R;
pmicdata->R ^= ROL32(pmicdata->L, 3);
pmicdata->L += pmicdata->R;
pmicdata->R ^= ROR32(pmicdata->L, 2);
pmicdata->L += pmicdata->R;
/* Clear the buffer */
pmicdata->M = 0;
pmicdata->nBytesInM = 0;
}
}
void rtw_secmicappend(struct mic_data *pmicdata, u8 *src, u32 nbytes)
{
/* This is simple */
while (nbytes > 0) {
rtw_secmicappendbyte(pmicdata, *src++);
nbytes--;
}
}
void rtw_secgetmic(struct mic_data *pmicdata, u8 *dst)
{
/* Append the minimum padding */
rtw_secmicappendbyte(pmicdata, 0x5a);
rtw_secmicappendbyte(pmicdata, 0);
rtw_secmicappendbyte(pmicdata, 0);
rtw_secmicappendbyte(pmicdata, 0);
rtw_secmicappendbyte(pmicdata, 0);
/* and then zeroes until the length is a multiple of 4 */
while (pmicdata->nBytesInM != 0)
rtw_secmicappendbyte(pmicdata, 0);
/* The appendByte function has already computed the result. */
secmicputuint32(dst, pmicdata->L);
secmicputuint32(dst + 4, pmicdata->R);
/* Reset to the empty message. */
secmicclear(pmicdata);
}
void rtw_seccalctkipmic(u8 *key, u8 *header, u8 *data, u32 data_len, u8 *mic_code, u8 pri)
{
struct mic_data micdata;
u8 priority[4] = {0x0, 0x0, 0x0, 0x0};
rtw_secmicsetkey(&micdata, key);
priority[0] = pri;
/* Michael MIC pseudo header: DA, SA, 3 x 0, Priority */
if (header[1] & 1) { /* ToDS==1 */
rtw_secmicappend(&micdata, &header[16], 6); /* DA */
if (header[1] & 2) /* From Ds==1 */
rtw_secmicappend(&micdata, &header[24], 6);
else
rtw_secmicappend(&micdata, &header[10], 6);
} else { /* ToDS==0 */
rtw_secmicappend(&micdata, &header[4], 6); /* DA */
if (header[1] & 2) /* From Ds==1 */
rtw_secmicappend(&micdata, &header[16], 6);
else
rtw_secmicappend(&micdata, &header[10], 6);
}
rtw_secmicappend(&micdata, &priority[0], 4);
rtw_secmicappend(&micdata, data, data_len);
rtw_secgetmic(&micdata, mic_code);
}
/* macros for extraction/creation of unsigned char/unsigned short values */
#define RotR1(v16) ((((v16) >> 1) & 0x7FFF) ^ (((v16) & 1) << 15))
#define Lo8(v16) ((u8)((v16) & 0x00FF))
#define Hi8(v16) ((u8)(((v16) >> 8) & 0x00FF))
#define Lo16(v32) ((u16)((v32) & 0xFFFF))
#define Hi16(v32) ((u16)(((v32) >> 16) & 0xFFFF))
#define Mk16(hi, lo) ((lo) ^ (((u16)(hi)) << 8))
/* select the Nth 16-bit word of the temporal key unsigned char array TK[] */
#define TK16(N) Mk16(tk[2*(N)+1], tk[2*(N)])
/* S-box lookup: 16 bits --> 16 bits */
#define _S_(v16) (Sbox1[0][Lo8(v16)] ^ Sbox1[1][Hi8(v16)])
/* fixed algorithm "parameters" */
#define PHASE1_LOOP_CNT 8 /* this needs to be "big enough" */
#define TA_SIZE 6 /* 48-bit transmitter address */
#define TK_SIZE 16 /* 128-bit temporal key */
#define P1K_SIZE 10 /* 80-bit Phase1 key */
#define RC4_KEY_SIZE 16 /* 128-bit RC4KEY (104 bits unknown) */
/* 2-unsigned char by 2-unsigned char subset of the full AES S-box table */
static const unsigned short Sbox1[2][256] = /* Sbox for hash (can be in ROM) */
{ {
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,
},
{ /* second half of table is unsigned char-reversed version of first! */
0xA5C6, 0x84F8, 0x99EE, 0x8DF6, 0x0DFF, 0xBDD6, 0xB1DE, 0x5491,
0x5060, 0x0302, 0xA9CE, 0x7D56, 0x19E7, 0x62B5, 0xE64D, 0x9AEC,
0x458F, 0x9D1F, 0x4089, 0x87FA, 0x15EF, 0xEBB2, 0xC98E, 0x0BFB,
0xEC41, 0x67B3, 0xFD5F, 0xEA45, 0xBF23, 0xF753, 0x96E4, 0x5B9B,
0xC275, 0x1CE1, 0xAE3D, 0x6A4C, 0x5A6C, 0x417E, 0x02F5, 0x4F83,
0x5C68, 0xF451, 0x34D1, 0x08F9, 0x93E2, 0x73AB, 0x5362, 0x3F2A,
0x0C08, 0x5295, 0x6546, 0x5E9D, 0x2830, 0xA137, 0x0F0A, 0xB52F,
0x090E, 0x3624, 0x9B1B, 0x3DDF, 0x26CD, 0x694E, 0xCD7F, 0x9FEA,
0x1B12, 0x9E1D, 0x7458, 0x2E34, 0x2D36, 0xB2DC, 0xEEB4, 0xFB5B,
0xF6A4, 0x4D76, 0x61B7, 0xCE7D, 0x7B52, 0x3EDD, 0x715E, 0x9713,
0xF5A6, 0x68B9, 0x0000, 0x2CC1, 0x6040, 0x1FE3, 0xC879, 0xEDB6,
0xBED4, 0x468D, 0xD967, 0x4B72, 0xDE94, 0xD498, 0xE8B0, 0x4A85,
0x6BBB, 0x2AC5, 0xE54F, 0x16ED, 0xC586, 0xD79A, 0x5566, 0x9411,
0xCF8A, 0x10E9, 0x0604, 0x81FE, 0xF0A0, 0x4478, 0xBA25, 0xE34B,
0xF3A2, 0xFE5D, 0xC080, 0x8A05, 0xAD3F, 0xBC21, 0x4870, 0x04F1,
0xDF63, 0xC177, 0x75AF, 0x6342, 0x3020, 0x1AE5, 0x0EFD, 0x6DBF,
0x4C81, 0x1418, 0x3526, 0x2FC3, 0xE1BE, 0xA235, 0xCC88, 0x392E,
0x5793, 0xF255, 0x82FC, 0x477A, 0xACC8, 0xE7BA, 0x2B32, 0x95E6,
0xA0C0, 0x9819, 0xD19E, 0x7FA3, 0x6644, 0x7E54, 0xAB3B, 0x830B,
0xCA8C, 0x29C7, 0xD36B, 0x3C28, 0x79A7, 0xE2BC, 0x1D16, 0x76AD,
0x3BDB, 0x5664, 0x4E74, 0x1E14, 0xDB92, 0x0A0C, 0x6C48, 0xE4B8,
0x5D9F, 0x6EBD, 0xEF43, 0xA6C4, 0xA839, 0xA431, 0x37D3, 0x8BF2,
0x32D5, 0x438B, 0x596E, 0xB7DA, 0x8C01, 0x64B1, 0xD29C, 0xE049,
0xB4D8, 0xFAAC, 0x07F3, 0x25CF, 0xAFCA, 0x8EF4, 0xE947, 0x1810,
0xD56F, 0x88F0, 0x6F4A, 0x725C, 0x2438, 0xF157, 0xC773, 0x5197,
0x23CB, 0x7CA1, 0x9CE8, 0x213E, 0xDD96, 0xDC61, 0x860D, 0x850F,
0x90E0, 0x427C, 0xC471, 0xAACC, 0xD890, 0x0506, 0x01F7, 0x121C,
0xA3C2, 0x5F6A, 0xF9AE, 0xD069, 0x9117, 0x5899, 0x273A, 0xB927,
0x38D9, 0x13EB, 0xB32B, 0x3322, 0xBBD2, 0x70A9, 0x8907, 0xA733,
0xB62D, 0x223C, 0x9215, 0x20C9, 0x4987, 0xFFAA, 0x7850, 0x7AA5,
0x8F03, 0xF859, 0x8009, 0x171A, 0xDA65, 0x31D7, 0xC684, 0xB8D0,
0xC382, 0xB029, 0x775A, 0x111E, 0xCB7B, 0xFCA8, 0xD66D, 0x3A2C,
}
};
/*
**********************************************************************
* Routine: Phase 1 -- generate P1K, given TA, TK, IV32
*
* Inputs:
* tk[] = temporal key [128 bits]
* ta[] = transmitter's MAC address [ 48 bits]
* iv32 = upper 32 bits of IV [ 32 bits]
* Output:
* p1k[] = Phase 1 key [ 80 bits]
*
* Note:
* This function only needs to be called every 2**16 packets,
* although in theory it could be called every packet.
*
**********************************************************************
*/
static void phase1(u16 *p1k, const u8 *tk, const u8 *ta, u32 iv32)
{
sint i;
/* Initialize the 80 bits of P1K[] from IV32 and TA[0..5] */
p1k[0] = Lo16(iv32);
p1k[1] = Hi16(iv32);
p1k[2] = Mk16(ta[1], ta[0]); /* use TA[] as little-endian */
p1k[3] = Mk16(ta[3], ta[2]);
p1k[4] = Mk16(ta[5], ta[4]);
/* Now compute an unbalanced Feistel cipher with 80-bit block */
/* size on the 80-bit block P1K[], using the 128-bit key TK[] */
for (i = 0; i < PHASE1_LOOP_CNT ; i++) {
/* Each add operation here is mod 2**16 */
p1k[0] += _S_(p1k[4] ^ TK16((i & 1) + 0));
p1k[1] += _S_(p1k[0] ^ TK16((i & 1) + 2));
p1k[2] += _S_(p1k[1] ^ TK16((i & 1) + 4));
p1k[3] += _S_(p1k[2] ^ TK16((i & 1) + 6));
p1k[4] += _S_(p1k[3] ^ TK16((i & 1) + 0));
p1k[4] += (unsigned short)i; /* avoid "slide attacks" */
}
}
/*
**********************************************************************
* Routine: Phase 2 -- generate RC4KEY, given TK, P1K, IV16
*
* Inputs:
* tk[] = Temporal key [128 bits]
* p1k[] = Phase 1 output key [ 80 bits]
* iv16 = low 16 bits of IV counter [ 16 bits]
* Output:
* rc4key[] = the key used to encrypt the packet [128 bits]
*
* Note:
* The value {TA,IV32,IV16} for Phase1/Phase2 must be unique
* across all packets using the same key TK value. Then, for a
* given value of TK[], this TKIP48 construction guarantees that
* the final RC4KEY value is unique across all packets.
*
* Suggested implementation optimization: if PPK[] is "overlaid"
* appropriately on RC4KEY[], there is no need for the final
* for loop below that copies the PPK[] result into RC4KEY[].
*
**********************************************************************
*/
static void phase2(u8 *rc4key, const u8 *tk, const u16 *p1k, u16 iv16)
{
sint i;
u16 PPK[6]; /* temporary key for mixing */
/* Note: all adds in the PPK[] equations below are mod 2**16 */
for (i = 0; i < 5; i++)
PPK[i] = p1k[i]; /* first, copy P1K to PPK */
PPK[5] = p1k[4] + iv16; /* next, add in IV16 */
/* Bijective non-linear mixing of the 96 bits of PPK[0..5] */
PPK[0] += _S_(PPK[5] ^ TK16(0)); /* Mix key in each "round" */
PPK[1] += _S_(PPK[0] ^ TK16(1));
PPK[2] += _S_(PPK[1] ^ TK16(2));
PPK[3] += _S_(PPK[2] ^ TK16(3));
PPK[4] += _S_(PPK[3] ^ TK16(4));
PPK[5] += _S_(PPK[4] ^ TK16(5)); /* Total # S-box lookups == 6 */
/* Final sweep: bijective, "linear". Rotates kill LSB correlations */
PPK[0] += RotR1(PPK[5] ^ TK16(6));
PPK[1] += RotR1(PPK[0] ^ TK16(7)); /* Use all of TK[] in Phase2 */
PPK[2] += RotR1(PPK[1]);
PPK[3] += RotR1(PPK[2]);
PPK[4] += RotR1(PPK[3]);
PPK[5] += RotR1(PPK[4]);
/* Note: At this point, for a given key TK[0..15], the 96-bit output */
/* value PPK[0..5] is guaranteed to be unique, as a function */
/* of the 96-bit "input" value {TA,IV32,IV16}. That is, P1K */
/* is now a keyed permutation of {TA,IV32,IV16}. */
/* Set RC4KEY[0..3], which includes "cleartext" portion of RC4 key */
rc4key[0] = Hi8(iv16); /* RC4KEY[0..2] is the WEP IV */
rc4key[1] = (Hi8(iv16) | 0x20) & 0x7F; /* Help avoid weak (FMS) keys */
rc4key[2] = Lo8(iv16);
rc4key[3] = Lo8((PPK[5] ^ TK16(0)) >> 1);
/* Copy 96 bits of PPK[0..5] to RC4KEY[4..15] (little-endian) */
for (i = 0; i < 6; i++) {
rc4key[4 + 2 * i] = Lo8(PPK[i]);
rc4key[5 + 2 * i] = Hi8(PPK[i]);
}
}
/* The hlen isn't include the IV */
u32 rtw_tkip_encrypt(_adapter *padapter, u8 *pxmitframe)
{
/* exclude ICV */
u16 pnl;
u32 pnh;
u8 rc4key[16];
u8 ttkey[16];
u8 crc[4];
u8 hw_hdr_offset = 0;
struct arc4context mycontext;
sint curfragnum, length;
u32 prwskeylen;
u8 *pframe, *payload, *iv, *prwskey;
union pn48 dot11txpn;
/* struct sta_info *stainfo; */
struct pkt_attrib *pattrib = &((struct xmit_frame *)pxmitframe)->attrib;
struct security_priv *psecuritypriv = &padapter->securitypriv;
struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
u32 res = _SUCCESS;
if (((struct xmit_frame *)pxmitframe)->buf_addr == NULL)
return _FAIL;
#ifdef CONFIG_USB_TX_AGGREGATION
hw_hdr_offset = TXDESC_SIZE +
(((struct xmit_frame *)pxmitframe)->pkt_offset * PACKET_OFFSET_SZ);
#else
#ifdef CONFIG_TX_EARLY_MODE
hw_hdr_offset = TXDESC_OFFSET + EARLY_MODE_INFO_SIZE;
#else
hw_hdr_offset = TXDESC_OFFSET;
#endif
#endif
pframe = ((struct xmit_frame *)pxmitframe)->buf_addr + hw_hdr_offset;
/* 4 start to encrypt each fragment */
if (pattrib->encrypt == _TKIP_) {
/*
if(pattrib->psta)
{
stainfo = pattrib->psta;
}
else
{
RTW_INFO("%s, call rtw_get_stainfo()\n", __func__);
stainfo=rtw_get_stainfo(&padapter->stapriv ,&pattrib->ra[0] );
}
*/
/* if (stainfo!=NULL) */
{
/*
if(!(stainfo->state &_FW_LINKED))
{
RTW_INFO("%s, psta->state(0x%x) != _FW_LINKED\n", __func__, stainfo->state);
return _FAIL;
}
*/
if (IS_MCAST(pattrib->ra))
prwskey = psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey;
else {
/* prwskey=&stainfo->dot118021x_UncstKey.skey[0]; */
prwskey = pattrib->dot118021x_UncstKey.skey;
}
prwskeylen = 16;
for (curfragnum = 0; curfragnum < pattrib->nr_frags; curfragnum++) {
iv = pframe + pattrib->hdrlen;
payload = pframe + pattrib->iv_len + pattrib->hdrlen;
GET_TKIP_PN(iv, dot11txpn);
pnl = (u16)(dot11txpn.val);
pnh = (u32)(dot11txpn.val >> 16);
phase1((u16 *)&ttkey[0], prwskey, &pattrib->ta[0], pnh);
phase2(&rc4key[0], prwskey, (u16 *)&ttkey[0], pnl);
if ((curfragnum + 1) == pattrib->nr_frags) { /* 4 the last fragment */
length = pattrib->last_txcmdsz - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len;
*((u32 *)crc) = cpu_to_le32(getcrc32(payload, length)); /* modified by Amy*/
arcfour_init(&mycontext, rc4key, 16);
arcfour_encrypt(&mycontext, payload, payload, length);
arcfour_encrypt(&mycontext, payload + length, crc, 4);
} else {
length = pxmitpriv->frag_len - pattrib->hdrlen - pattrib->iv_len - pattrib->icv_len ;
*((u32 *)crc) = cpu_to_le32(getcrc32(payload, length)); /* modified by Amy*/
arcfour_init(&mycontext, rc4key, 16);
arcfour_encrypt(&mycontext, payload, payload, length);
arcfour_encrypt(&mycontext, payload + length, crc, 4);
pframe += pxmitpriv->frag_len;
pframe = (u8 *)RND4((SIZE_PTR)(pframe));
}
}
TKIP_SW_ENC_CNT_INC(psecuritypriv, pattrib->ra);
}
/*
else{
RTW_INFO("%s, psta==NUL\n", __func__);
res=_FAIL;
}
*/
}
return res;
}
/* The hlen isn't include the IV */
u32 rtw_tkip_decrypt(_adapter *padapter, u8 *precvframe)
{
/* exclude ICV */
u16 pnl;
u32 pnh;
u8 rc4key[16];
u8 ttkey[16];
u8 crc[4];
struct arc4context mycontext;
sint length;
u32 prwskeylen;
u8 *pframe, *payload, *iv, *prwskey;
union pn48 dot11txpn;
struct sta_info *stainfo;
struct rx_pkt_attrib *prxattrib = &((union recv_frame *)precvframe)->u.hdr.attrib;
struct security_priv *psecuritypriv = &padapter->securitypriv;
/* struct recv_priv *precvpriv=&padapter->recvpriv; */
u32 res = _SUCCESS;
pframe = (unsigned char *)((union recv_frame *)precvframe)->u.hdr.rx_data;
/* 4 start to decrypt recvframe */
if (prxattrib->encrypt == _TKIP_) {
stainfo = rtw_get_stainfo(&padapter->stapriv , &prxattrib->ta[0]);
if (stainfo != NULL) {
if (IS_MCAST(prxattrib->ra)) {
static systime start = 0;
static u32 no_gkey_bc_cnt = 0;
static u32 no_gkey_mc_cnt = 0;
if (psecuritypriv->binstallGrpkey == _FALSE) {
res = _FAIL;
if (start == 0)
start = rtw_get_current_time();
if (is_broadcast_mac_addr(prxattrib->ra))
no_gkey_bc_cnt++;
else
no_gkey_mc_cnt++;
if (rtw_get_passing_time_ms(start) > 1000) {
if (no_gkey_bc_cnt || no_gkey_mc_cnt) {
RTW_PRINT(FUNC_ADPT_FMT" no_gkey_bc_cnt:%u, no_gkey_mc_cnt:%u\n",
FUNC_ADPT_ARG(padapter), no_gkey_bc_cnt, no_gkey_mc_cnt);
}
start = rtw_get_current_time();
no_gkey_bc_cnt = 0;
no_gkey_mc_cnt = 0;
}
goto exit;
}
if (no_gkey_bc_cnt || no_gkey_mc_cnt) {
RTW_PRINT(FUNC_ADPT_FMT" gkey installed. no_gkey_bc_cnt:%u, no_gkey_mc_cnt:%u\n",
FUNC_ADPT_ARG(padapter), no_gkey_bc_cnt, no_gkey_mc_cnt);
}
start = 0;
no_gkey_bc_cnt = 0;
no_gkey_mc_cnt = 0;
/* RTW_INFO("rx bc/mc packets, to perform sw rtw_tkip_decrypt\n"); */
/* prwskey = psecuritypriv->dot118021XGrpKey[psecuritypriv->dot118021XGrpKeyid].skey; */
prwskey = psecuritypriv->dot118021XGrpKey[prxattrib->key_index].skey;
prwskeylen = 16;
} else {
prwskey = &stainfo->dot118021x_UncstKey.skey[0];
prwskeylen = 16;
}
iv = pframe + prxattrib->hdrlen;
payload = pframe + prxattrib->iv_len + prxattrib->hdrlen;
length = ((union recv_frame *)precvframe)->u.hdr.len - prxattrib->hdrlen - prxattrib->iv_len;
GET_TKIP_PN(iv, dot11txpn);
pnl = (u16)(dot11txpn.val);
pnh = (u32)(dot11txpn.val >> 16);
phase1((u16 *)&ttkey[0], prwskey, &prxattrib->ta[0], pnh);
phase2(&rc4key[0], prwskey, (unsigned short *)&ttkey[0], pnl);
/* 4 decrypt payload include icv */
arcfour_init(&mycontext, rc4key, 16);
arcfour_encrypt(&mycontext, payload, payload, length);
*((u32 *)crc) = le32_to_cpu(getcrc32(payload, length - 4));
if (crc[3] != payload[length - 1] || crc[2] != payload[length - 2] || crc[1] != payload[length - 3] || crc[0] != payload[length - 4]) {
res = _FAIL;
}
TKIP_SW_DEC_CNT_INC(psecuritypriv, prxattrib->ra);
} else {
res = _FAIL;
}
}
exit:
return res;
}
/* 3 =====AES related===== */
#define MAX_MSG_SIZE 2048
/*****************************/
/******** SBOX Table *********/
/*****************************/
static u8 sbox_table[256] = {
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5,
0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0,
0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc,
0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a,
0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0,
0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b,
0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85,
0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5,
0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17,
0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88,
0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,
0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9,
0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6,
0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e,
0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94,
0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68,
0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16
};
/*****************************/
/**** Function Prototypes ****/
/*****************************/
static void bitwise_xor(u8 *ina, u8 *inb, u8 *out);
static void construct_mic_iv(
u8 *mic_header1,
sint qc_exists,
sint a4_exists,
u8 *mpdu,
uint payload_length,
u8 *pn_vector,
uint frtype);/* add for CONFIG_IEEE80211W, none 11w also can use */
static void construct_mic_header1(
u8 *mic_header1,
sint header_length,
u8 *mpdu,
uint frtype);/* add for CONFIG_IEEE80211W, none 11w also can use */
static void construct_mic_header2(
u8 *mic_header2,
u8 *mpdu,
sint a4_exists,
sint qc_exists);
static void construct_ctr_preload(
u8 *ctr_preload,
sint a4_exists,
sint qc_exists,
u8 *mpdu,
u8 *pn_vector,
sint c,
uint frtype);/* add for CONFIG_IEEE80211W, none 11w also can use */
static void xor_128(u8 *a, u8 *b, u8 *out);
static void xor_32(u8 *a, u8 *b, u8 *out);
static u8 sbox(u8 a);
static void next_key(u8 *key, sint round);
static void byte_sub(u8 *in, u8 *out);
static void shift_row(u8 *in, u8 *out);
static void mix_column(u8 *in, u8 *out);
static void aes128k128d(u8 *key, u8 *data, u8 *ciphertext);
/****************************************/
/* aes128k128d() */
/* Performs a 128 bit AES encrypt with */
/* 128 bit data. */
/****************************************/
static void xor_128(u8 *a, u8 *b, u8 *out)
{
sint i;
for (i = 0; i < 16; i++)
out[i] = a[i] ^ b[i];
}