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aes_ccmp.c
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1 /*
2  * Copyright (c) 1996, 2003 VIA Networking Technologies, Inc.
3  * All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License along
16  * with this program; if not, write to the Free Software Foundation, Inc.,
17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * File: aes_ccmp.c
20  *
21  * Purpose: AES_CCMP decryption
22  *
23  * Author: Warren Hsu
24  *
25  * Date: Feb 15, 2005
26  *
27  * Functions:
28  * AESbGenCCMP - Parsing RX-packet
29  *
30  * Revision History:
31  */
32 
33 #include "device.h"
34 #include "80211hdr.h"
35 
36 /*--------------------- Static Definitions -------------------------*/
37 
38 /*--------------------- Static Classes ----------------------------*/
39 
40 /*--------------------- Static Variables --------------------------*/
41 
42 /*
43  * SBOX Table
44  */
45 
46 BYTE sbox_table[256] = {
47  0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
48  0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
49  0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
50  0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
51  0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
52  0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
53  0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
54  0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
55  0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
56  0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
57  0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
58  0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
59  0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
60  0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
61  0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
62  0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16
63 };
64 
65 BYTE dot2_table[256] = {
66  0x00, 0x02, 0x04, 0x06, 0x08, 0x0a, 0x0c, 0x0e, 0x10, 0x12, 0x14, 0x16, 0x18, 0x1a, 0x1c, 0x1e,
67  0x20, 0x22, 0x24, 0x26, 0x28, 0x2a, 0x2c, 0x2e, 0x30, 0x32, 0x34, 0x36, 0x38, 0x3a, 0x3c, 0x3e,
68  0x40, 0x42, 0x44, 0x46, 0x48, 0x4a, 0x4c, 0x4e, 0x50, 0x52, 0x54, 0x56, 0x58, 0x5a, 0x5c, 0x5e,
69  0x60, 0x62, 0x64, 0x66, 0x68, 0x6a, 0x6c, 0x6e, 0x70, 0x72, 0x74, 0x76, 0x78, 0x7a, 0x7c, 0x7e,
70  0x80, 0x82, 0x84, 0x86, 0x88, 0x8a, 0x8c, 0x8e, 0x90, 0x92, 0x94, 0x96, 0x98, 0x9a, 0x9c, 0x9e,
71  0xa0, 0xa2, 0xa4, 0xa6, 0xa8, 0xaa, 0xac, 0xae, 0xb0, 0xb2, 0xb4, 0xb6, 0xb8, 0xba, 0xbc, 0xbe,
72  0xc0, 0xc2, 0xc4, 0xc6, 0xc8, 0xca, 0xcc, 0xce, 0xd0, 0xd2, 0xd4, 0xd6, 0xd8, 0xda, 0xdc, 0xde,
73  0xe0, 0xe2, 0xe4, 0xe6, 0xe8, 0xea, 0xec, 0xee, 0xf0, 0xf2, 0xf4, 0xf6, 0xf8, 0xfa, 0xfc, 0xfe,
74  0x1b, 0x19, 0x1f, 0x1d, 0x13, 0x11, 0x17, 0x15, 0x0b, 0x09, 0x0f, 0x0d, 0x03, 0x01, 0x07, 0x05,
75  0x3b, 0x39, 0x3f, 0x3d, 0x33, 0x31, 0x37, 0x35, 0x2b, 0x29, 0x2f, 0x2d, 0x23, 0x21, 0x27, 0x25,
76  0x5b, 0x59, 0x5f, 0x5d, 0x53, 0x51, 0x57, 0x55, 0x4b, 0x49, 0x4f, 0x4d, 0x43, 0x41, 0x47, 0x45,
77  0x7b, 0x79, 0x7f, 0x7d, 0x73, 0x71, 0x77, 0x75, 0x6b, 0x69, 0x6f, 0x6d, 0x63, 0x61, 0x67, 0x65,
78  0x9b, 0x99, 0x9f, 0x9d, 0x93, 0x91, 0x97, 0x95, 0x8b, 0x89, 0x8f, 0x8d, 0x83, 0x81, 0x87, 0x85,
79  0xbb, 0xb9, 0xbf, 0xbd, 0xb3, 0xb1, 0xb7, 0xb5, 0xab, 0xa9, 0xaf, 0xad, 0xa3, 0xa1, 0xa7, 0xa5,
80  0xdb, 0xd9, 0xdf, 0xdd, 0xd3, 0xd1, 0xd7, 0xd5, 0xcb, 0xc9, 0xcf, 0xcd, 0xc3, 0xc1, 0xc7, 0xc5,
81  0xfb, 0xf9, 0xff, 0xfd, 0xf3, 0xf1, 0xf7, 0xf5, 0xeb, 0xe9, 0xef, 0xed, 0xe3, 0xe1, 0xe7, 0xe5
82 };
83 
84 BYTE dot3_table[256] = {
85  0x00, 0x03, 0x06, 0x05, 0x0c, 0x0f, 0x0a, 0x09, 0x18, 0x1b, 0x1e, 0x1d, 0x14, 0x17, 0x12, 0x11,
86  0x30, 0x33, 0x36, 0x35, 0x3c, 0x3f, 0x3a, 0x39, 0x28, 0x2b, 0x2e, 0x2d, 0x24, 0x27, 0x22, 0x21,
87  0x60, 0x63, 0x66, 0x65, 0x6c, 0x6f, 0x6a, 0x69, 0x78, 0x7b, 0x7e, 0x7d, 0x74, 0x77, 0x72, 0x71,
88  0x50, 0x53, 0x56, 0x55, 0x5c, 0x5f, 0x5a, 0x59, 0x48, 0x4b, 0x4e, 0x4d, 0x44, 0x47, 0x42, 0x41,
89  0xc0, 0xc3, 0xc6, 0xc5, 0xcc, 0xcf, 0xca, 0xc9, 0xd8, 0xdb, 0xde, 0xdd, 0xd4, 0xd7, 0xd2, 0xd1,
90  0xf0, 0xf3, 0xf6, 0xf5, 0xfc, 0xff, 0xfa, 0xf9, 0xe8, 0xeb, 0xee, 0xed, 0xe4, 0xe7, 0xe2, 0xe1,
91  0xa0, 0xa3, 0xa6, 0xa5, 0xac, 0xaf, 0xaa, 0xa9, 0xb8, 0xbb, 0xbe, 0xbd, 0xb4, 0xb7, 0xb2, 0xb1,
92  0x90, 0x93, 0x96, 0x95, 0x9c, 0x9f, 0x9a, 0x99, 0x88, 0x8b, 0x8e, 0x8d, 0x84, 0x87, 0x82, 0x81,
93  0x9b, 0x98, 0x9d, 0x9e, 0x97, 0x94, 0x91, 0x92, 0x83, 0x80, 0x85, 0x86, 0x8f, 0x8c, 0x89, 0x8a,
94  0xab, 0xa8, 0xad, 0xae, 0xa7, 0xa4, 0xa1, 0xa2, 0xb3, 0xb0, 0xb5, 0xb6, 0xbf, 0xbc, 0xb9, 0xba,
95  0xfb, 0xf8, 0xfd, 0xfe, 0xf7, 0xf4, 0xf1, 0xf2, 0xe3, 0xe0, 0xe5, 0xe6, 0xef, 0xec, 0xe9, 0xea,
96  0xcb, 0xc8, 0xcd, 0xce, 0xc7, 0xc4, 0xc1, 0xc2, 0xd3, 0xd0, 0xd5, 0xd6, 0xdf, 0xdc, 0xd9, 0xda,
97  0x5b, 0x58, 0x5d, 0x5e, 0x57, 0x54, 0x51, 0x52, 0x43, 0x40, 0x45, 0x46, 0x4f, 0x4c, 0x49, 0x4a,
98  0x6b, 0x68, 0x6d, 0x6e, 0x67, 0x64, 0x61, 0x62, 0x73, 0x70, 0x75, 0x76, 0x7f, 0x7c, 0x79, 0x7a,
99  0x3b, 0x38, 0x3d, 0x3e, 0x37, 0x34, 0x31, 0x32, 0x23, 0x20, 0x25, 0x26, 0x2f, 0x2c, 0x29, 0x2a,
100  0x0b, 0x08, 0x0d, 0x0e, 0x07, 0x04, 0x01, 0x02, 0x13, 0x10, 0x15, 0x16, 0x1f, 0x1c, 0x19, 0x1a
101 };
102 
103 /*--------------------- Static Functions --------------------------*/
104 
105 /*--------------------- Export Variables --------------------------*/
106 
107 /*--------------------- Export Functions --------------------------*/
108 
109 static void xor_128(BYTE *a, BYTE *b, BYTE *out)
110 {
111  PDWORD dwPtrA = (PDWORD) a;
112  PDWORD dwPtrB = (PDWORD) b;
113  PDWORD dwPtrOut = (PDWORD) out;
114 
115  (*dwPtrOut++) = (*dwPtrA++) ^ (*dwPtrB++);
116  (*dwPtrOut++) = (*dwPtrA++) ^ (*dwPtrB++);
117  (*dwPtrOut++) = (*dwPtrA++) ^ (*dwPtrB++);
118  (*dwPtrOut++) = (*dwPtrA++) ^ (*dwPtrB++);
119 }
120 
121 
122 static void xor_32(BYTE *a, BYTE *b, BYTE *out)
123 {
124  PDWORD dwPtrA = (PDWORD) a;
125  PDWORD dwPtrB = (PDWORD) b;
126  PDWORD dwPtrOut = (PDWORD) out;
127 
128  (*dwPtrOut++) = (*dwPtrA++) ^ (*dwPtrB++);
129 }
130 
131 void AddRoundKey(BYTE *key, int round)
132 {
133  BYTE sbox_key[4];
134  BYTE rcon_table[10] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36};
135 
136  sbox_key[0] = sbox_table[key[13]];
137  sbox_key[1] = sbox_table[key[14]];
138  sbox_key[2] = sbox_table[key[15]];
139  sbox_key[3] = sbox_table[key[12]];
140 
141  key[0] = key[0] ^ rcon_table[round];
142  xor_32(&key[0], sbox_key, &key[0]);
143 
144  xor_32(&key[4], &key[0], &key[4]);
145  xor_32(&key[8], &key[4], &key[8]);
146  xor_32(&key[12], &key[8], &key[12]);
147 }
148 
149 void SubBytes(BYTE *in, BYTE *out)
150 {
151  int i;
152 
153  for (i = 0; i < 16; i++)
154  out[i] = sbox_table[in[i]];
155 }
156 
157 void ShiftRows(BYTE *in, BYTE *out)
158 {
159  out[0] = in[0];
160  out[1] = in[5];
161  out[2] = in[10];
162  out[3] = in[15];
163  out[4] = in[4];
164  out[5] = in[9];
165  out[6] = in[14];
166  out[7] = in[3];
167  out[8] = in[8];
168  out[9] = in[13];
169  out[10] = in[2];
170  out[11] = in[7];
171  out[12] = in[12];
172  out[13] = in[1];
173  out[14] = in[6];
174  out[15] = in[11];
175 }
176 
177 void MixColumns(BYTE *in, BYTE *out)
178 {
179 
180  out[0] = dot2_table[in[0]] ^ dot3_table[in[1]] ^ in[2] ^ in[3];
181  out[1] = in[0] ^ dot2_table[in[1]] ^ dot3_table[in[2]] ^ in[3];
182  out[2] = in[0] ^ in[1] ^ dot2_table[in[2]] ^ dot3_table[in[3]];
183  out[3] = dot3_table[in[0]] ^ in[1] ^ in[2] ^ dot2_table[in[3]];
184 }
185 
186 void AESv128(BYTE *key, BYTE *data, BYTE *ciphertext)
187 {
188  int i;
189  int round;
190  BYTE TmpdataA[16];
191  BYTE TmpdataB[16];
192  BYTE abyRoundKey[16];
193 
194  for (i = 0; i < 16; i++)
195  abyRoundKey[i] = key[i];
196 
197  for (round = 0; round < 11; round++) {
198  if (round == 0) {
199  xor_128(abyRoundKey, data, ciphertext);
200  AddRoundKey(abyRoundKey, round);
201  } else if (round == 10) {
202  SubBytes(ciphertext, TmpdataA);
203  ShiftRows(TmpdataA, TmpdataB);
204  xor_128(TmpdataB, abyRoundKey, ciphertext);
205  } else { /* round 1 ~ 9 */
206  SubBytes(ciphertext, TmpdataA);
207  ShiftRows(TmpdataA, TmpdataB);
208  MixColumns(&TmpdataB[0], &TmpdataA[0]);
209  MixColumns(&TmpdataB[4], &TmpdataA[4]);
210  MixColumns(&TmpdataB[8], &TmpdataA[8]);
211  MixColumns(&TmpdataB[12], &TmpdataA[12]);
212  xor_128(TmpdataA, abyRoundKey, ciphertext);
213  AddRoundKey(abyRoundKey, round);
214  }
215  }
216 
217 }
218 
219 /*
220  * Description: AES decryption
221  *
222  * Parameters:
223  * In:
224  * pbyRxKey - The key used to decrypt
225  * pbyFrame - Starting address of packet header
226  * wFrameSize - Total packet size including CRC
227  * Out:
228  * none
229  *
230  * Return Value: MIC compare result
231  *
232  */
233 
234 BOOL AESbGenCCMP(PBYTE pbyRxKey, PBYTE pbyFrame, WORD wFrameSize)
235 {
236  BYTE abyNonce[13];
237  BYTE MIC_IV[16];
238  BYTE MIC_HDR1[16];
239  BYTE MIC_HDR2[16];
240  BYTE abyMIC[16];
241  BYTE abyCTRPLD[16];
242  BYTE abyTmp[16];
243  BYTE abyPlainText[16];
244  BYTE abyLastCipher[16];
245 
246  PS802_11Header pMACHeader = (PS802_11Header) pbyFrame;
247  PBYTE pbyIV;
248  PBYTE pbyPayload;
249  WORD wHLen = 22;
250  /* 8 is IV, 8 is MIC, 4 is CRC */
251  WORD wPayloadSize = wFrameSize - 8 - 8 - 4 - WLAN_HDR_ADDR3_LEN;
252  BOOL bA4 = FALSE;
253  BYTE byTmp;
254  WORD wCnt;
255  int ii, jj, kk;
256 
257  pbyIV = pbyFrame + WLAN_HDR_ADDR3_LEN;
258  if (WLAN_GET_FC_TODS(*(PWORD) pbyFrame) &&
259  WLAN_GET_FC_FROMDS(*(PWORD) pbyFrame)) {
260  bA4 = TRUE;
261  pbyIV += 6; /* 6 is 802.11 address4 */
262  wHLen += 6;
263  wPayloadSize -= 6;
264  }
265  pbyPayload = pbyIV + 8; /* IV-length */
266 
267  abyNonce[0] = 0x00; /* now is 0, if Qos here will be priority */
268  memcpy(&(abyNonce[1]), pMACHeader->abyAddr2, ETH_ALEN);
269  abyNonce[7] = pbyIV[7];
270  abyNonce[8] = pbyIV[6];
271  abyNonce[9] = pbyIV[5];
272  abyNonce[10] = pbyIV[4];
273  abyNonce[11] = pbyIV[1];
274  abyNonce[12] = pbyIV[0];
275 
276  /* MIC_IV */
277  MIC_IV[0] = 0x59;
278  memcpy(&(MIC_IV[1]), &(abyNonce[0]), 13);
279  MIC_IV[14] = (BYTE)(wPayloadSize >> 8);
280  MIC_IV[15] = (BYTE)(wPayloadSize & 0xff);
281 
282  /* MIC_HDR1 */
283  MIC_HDR1[0] = (BYTE)(wHLen >> 8);
284  MIC_HDR1[1] = (BYTE)(wHLen & 0xff);
285  byTmp = (BYTE)(pMACHeader->wFrameCtl & 0xff);
286  MIC_HDR1[2] = byTmp & 0x8f;
287  byTmp = (BYTE)(pMACHeader->wFrameCtl >> 8);
288  byTmp &= 0x87;
289  MIC_HDR1[3] = byTmp | 0x40;
290  memcpy(&(MIC_HDR1[4]), pMACHeader->abyAddr1, ETH_ALEN);
291  memcpy(&(MIC_HDR1[10]), pMACHeader->abyAddr2, ETH_ALEN);
292 
293  /* MIC_HDR2 */
294  memcpy(&(MIC_HDR2[0]), pMACHeader->abyAddr3, ETH_ALEN);
295  byTmp = (BYTE)(pMACHeader->wSeqCtl & 0xff);
296  MIC_HDR2[6] = byTmp & 0x0f;
297  MIC_HDR2[7] = 0;
298 
299  if (bA4) {
300  memcpy(&(MIC_HDR2[8]), pMACHeader->abyAddr4, ETH_ALEN);
301  } else {
302  MIC_HDR2[8] = 0x00;
303  MIC_HDR2[9] = 0x00;
304  MIC_HDR2[10] = 0x00;
305  MIC_HDR2[11] = 0x00;
306  MIC_HDR2[12] = 0x00;
307  MIC_HDR2[13] = 0x00;
308  }
309  MIC_HDR2[14] = 0x00;
310  MIC_HDR2[15] = 0x00;
311 
312  /* CCMP */
313  AESv128(pbyRxKey, MIC_IV, abyMIC);
314  for (kk = 0; kk < 16; kk++)
315  abyTmp[kk] = MIC_HDR1[kk] ^ abyMIC[kk];
316 
317  AESv128(pbyRxKey, abyTmp, abyMIC);
318  for (kk = 0; kk < 16; kk++)
319  abyTmp[kk] = MIC_HDR2[kk] ^ abyMIC[kk];
320 
321  AESv128(pbyRxKey, abyTmp, abyMIC);
322 
323  wCnt = 1;
324  abyCTRPLD[0] = 0x01;
325  memcpy(&(abyCTRPLD[1]), &(abyNonce[0]), 13);
326 
327  for (jj = wPayloadSize; jj > 16; jj = jj-16) {
328 
329  abyCTRPLD[14] = (BYTE) (wCnt >> 8);
330  abyCTRPLD[15] = (BYTE) (wCnt & 0xff);
331 
332  AESv128(pbyRxKey, abyCTRPLD, abyTmp);
333 
334  for (kk = 0; kk < 16; kk++)
335  abyPlainText[kk] = abyTmp[kk] ^ pbyPayload[kk];
336 
337  for (kk = 0; kk < 16; kk++)
338  abyTmp[kk] = abyMIC[kk] ^ abyPlainText[kk];
339 
340  AESv128(pbyRxKey, abyTmp, abyMIC);
341 
342  memcpy(pbyPayload, abyPlainText, 16);
343  wCnt++;
344  pbyPayload += 16;
345  } /* for wPayloadSize */
346 
347  /* last payload */
348  memcpy(&(abyLastCipher[0]), pbyPayload, jj);
349  for (ii = jj; ii < 16; ii++)
350  abyLastCipher[ii] = 0x00;
351 
352  abyCTRPLD[14] = (BYTE) (wCnt >> 8);
353  abyCTRPLD[15] = (BYTE) (wCnt & 0xff);
354 
355  AESv128(pbyRxKey, abyCTRPLD, abyTmp);
356  for (kk = 0; kk < 16; kk++)
357  abyPlainText[kk] = abyTmp[kk] ^ abyLastCipher[kk];
358 
359  memcpy(pbyPayload, abyPlainText, jj);
360  pbyPayload += jj;
361 
362  /* for MIC calculation */
363  for (ii = jj; ii < 16; ii++)
364  abyPlainText[ii] = 0x00;
365  for (kk = 0; kk < 16; kk++)
366  abyTmp[kk] = abyMIC[kk] ^ abyPlainText[kk];
367 
368  AESv128(pbyRxKey, abyTmp, abyMIC);
369 
370  /* => above is the calculated MIC */
371 
372  wCnt = 0;
373  abyCTRPLD[14] = (BYTE) (wCnt >> 8);
374  abyCTRPLD[15] = (BYTE) (wCnt & 0xff);
375  AESv128(pbyRxKey, abyCTRPLD, abyTmp);
376 
377  for (kk = 0; kk < 8; kk++)
378  abyTmp[kk] = abyTmp[kk] ^ pbyPayload[kk];
379 
380  /* => above is the packet dec-MIC */
381 
382  if (!memcmp(abyMIC, abyTmp, 8))
383  return TRUE;
384  else
385  return FALSE;
386 }
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