1/*
2 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
3 * Copyright (c) 2002-2008 Atheros Communications, Inc.
4 *
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 *
17 * $FreeBSD$
18 */
19#include "opt_ah.h"
20
21#include "ah.h"
22#include "ah_internal.h"
23
24#include "ar5212/ar5212.h"
25#include "ar5212/ar5212reg.h"
26#include "ar5212/ar5212desc.h"
27
28/*
29 * Note: The key cache hardware requires that each double-word
30 * pair be written in even/odd order (since the destination is
31 * a 64-bit register).  Don't reorder the writes in this code
32 * w/o considering this!
33 */
34#define	KEY_XOR			0xaa
35
36#define	IS_MIC_ENABLED(ah) \
37	(AH5212(ah)->ah_staId1Defaults & AR_STA_ID1_CRPT_MIC_ENABLE)
38
39/*
40 * Return the size of the hardware key cache.
41 */
42uint32_t
43ar5212GetKeyCacheSize(struct ath_hal *ah)
44{
45	return AH_PRIVATE(ah)->ah_caps.halKeyCacheSize;
46}
47
48/*
49 * Return true if the specific key cache entry is valid.
50 */
51HAL_BOOL
52ar5212IsKeyCacheEntryValid(struct ath_hal *ah, uint16_t entry)
53{
54	if (entry < AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
55		uint32_t val = OS_REG_READ(ah, AR_KEYTABLE_MAC1(entry));
56		if (val & AR_KEYTABLE_VALID)
57			return AH_TRUE;
58	}
59	return AH_FALSE;
60}
61
62/*
63 * Clear the specified key cache entry and any associated MIC entry.
64 */
65HAL_BOOL
66ar5212ResetKeyCacheEntry(struct ath_hal *ah, uint16_t entry)
67{
68	uint32_t keyType;
69
70	if (entry >= AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
71		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
72		    __func__, entry);
73		return AH_FALSE;
74	}
75	keyType = OS_REG_READ(ah, AR_KEYTABLE_TYPE(entry));
76
77	/* XXX why not clear key type/valid bit first? */
78	OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0);
79	OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0);
80	OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0);
81	OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0);
82	OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0);
83	OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), AR_KEYTABLE_TYPE_CLR);
84	OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0);
85	OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0);
86	if (keyType == AR_KEYTABLE_TYPE_TKIP && IS_MIC_ENABLED(ah)) {
87		uint16_t micentry = entry+64;	/* MIC goes at slot+64 */
88
89		HALASSERT(micentry < AH_PRIVATE(ah)->ah_caps.halKeyCacheSize);
90		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), 0);
91		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);
92		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), 0);
93		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);
94		/* NB: key type and MAC are known to be ok */
95	}
96	return AH_TRUE;
97}
98
99/*
100 * Sets the mac part of the specified key cache entry (and any
101 * associated MIC entry) and mark them valid.
102 *
103 * Since mac[0] is shifted off and not presented to the hardware,
104 * it does double duty as a "don't use for unicast, use for multicast
105 * matching" flag. This interface should later be extended to
106 * explicitly do that rather than overloading a bit in the MAC
107 * address.
108 */
109HAL_BOOL
110ar5212SetKeyCacheEntryMac(struct ath_hal *ah, uint16_t entry, const uint8_t *mac)
111{
112	uint32_t macHi, macLo;
113	uint32_t unicast_flag = AR_KEYTABLE_VALID;
114
115	if (entry >= AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
116		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
117		    __func__, entry);
118		return AH_FALSE;
119	}
120	/*
121	 * Set MAC address -- shifted right by 1.  MacLo is
122	 * the 4 MSBs, and MacHi is the 2 LSBs.
123	 */
124	if (mac != AH_NULL) {
125		/*
126		 * AR_KEYTABLE_VALID indicates that the address is a unicast
127		 * address, which must match the transmitter address for
128		 * decrypting frames.
129		 * Not setting this bit allows the hardware to use the key
130		 * for multicast frame decryption.
131		 */
132		if (mac[0] & 0x01)
133			unicast_flag = 0;
134
135		macHi = (mac[5] << 8) | mac[4];
136		macLo = (mac[3] << 24)| (mac[2] << 16)
137		      | (mac[1] << 8) | mac[0];
138		macLo >>= 1;
139		macLo |= (macHi & 1) << 31;	/* carry */
140		macHi >>= 1;
141	} else {
142		macLo = macHi = 0;
143	}
144	OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
145	OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi | unicast_flag);
146	return AH_TRUE;
147}
148
149/*
150 * Sets the contents of the specified key cache entry
151 * and any associated MIC entry.
152 */
153HAL_BOOL
154ar5212SetKeyCacheEntry(struct ath_hal *ah, uint16_t entry,
155                       const HAL_KEYVAL *k, const uint8_t *mac,
156                       int xorKey)
157{
158	struct ath_hal_5212 *ahp = AH5212(ah);
159	const HAL_CAPABILITIES *pCap = &AH_PRIVATE(ah)->ah_caps;
160	uint32_t key0, key1, key2, key3, key4;
161	uint32_t keyType;
162	uint32_t xorMask = xorKey ?
163		(KEY_XOR << 24 | KEY_XOR << 16 | KEY_XOR << 8 | KEY_XOR) : 0;
164
165	if (entry >= pCap->halKeyCacheSize) {
166		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
167		    __func__, entry);
168		return AH_FALSE;
169	}
170	switch (k->kv_type) {
171	case HAL_CIPHER_AES_OCB:
172		keyType = AR_KEYTABLE_TYPE_AES;
173		break;
174	case HAL_CIPHER_AES_CCM:
175		if (!pCap->halCipherAesCcmSupport) {
176			HALDEBUG(ah, HAL_DEBUG_ANY,
177			    "%s: AES-CCM not supported by mac rev 0x%x\n",
178			    __func__, AH_PRIVATE(ah)->ah_macRev);
179			return AH_FALSE;
180		}
181		keyType = AR_KEYTABLE_TYPE_CCM;
182		break;
183	case HAL_CIPHER_TKIP:
184		keyType = AR_KEYTABLE_TYPE_TKIP;
185		if (IS_MIC_ENABLED(ah) && entry+64 >= pCap->halKeyCacheSize) {
186			HALDEBUG(ah, HAL_DEBUG_ANY,
187			    "%s: entry %u inappropriate for TKIP\n",
188			    __func__, entry);
189			return AH_FALSE;
190		}
191		break;
192	case HAL_CIPHER_WEP:
193		if (k->kv_len < 40 / NBBY) {
194			HALDEBUG(ah, HAL_DEBUG_ANY,
195			    "%s: WEP key length %u too small\n",
196			    __func__, k->kv_len);
197			return AH_FALSE;
198		}
199		if (k->kv_len <= 40 / NBBY)
200			keyType = AR_KEYTABLE_TYPE_40;
201		else if (k->kv_len <= 104 / NBBY)
202			keyType = AR_KEYTABLE_TYPE_104;
203		else
204			keyType = AR_KEYTABLE_TYPE_128;
205		break;
206	case HAL_CIPHER_CLR:
207		keyType = AR_KEYTABLE_TYPE_CLR;
208		break;
209	default:
210		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: cipher %u not supported\n",
211		    __func__, k->kv_type);
212		return AH_FALSE;
213	}
214
215	key0 = LE_READ_4(k->kv_val+0) ^ xorMask;
216	key1 = (LE_READ_2(k->kv_val+4) ^ xorMask) & 0xffff;
217	key2 = LE_READ_4(k->kv_val+6) ^ xorMask;
218	key3 = (LE_READ_2(k->kv_val+10) ^ xorMask) & 0xffff;
219	key4 = LE_READ_4(k->kv_val+12) ^ xorMask;
220	if (k->kv_len <= 104 / NBBY)
221		key4 &= 0xff;
222
223	/*
224	 * Note: key cache hardware requires that each double-word
225	 * pair be written in even/odd order (since the destination is
226	 * a 64-bit register).  Don't reorder these writes w/o
227	 * considering this!
228	 */
229	if (keyType == AR_KEYTABLE_TYPE_TKIP && IS_MIC_ENABLED(ah)) {
230		uint16_t micentry = entry+64;	/* MIC goes at slot+64 */
231		uint32_t mic0, mic1, mic2, mic3, mic4;
232
233		/*
234		 * Invalidate the encrypt/decrypt key until the MIC
235		 * key is installed so pending rx frames will fail
236		 * with decrypt errors rather than a MIC error.
237		 */
238		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), ~key0);
239		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), ~key1);
240		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
241		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
242		OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
243		OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
244		(void) ar5212SetKeyCacheEntryMac(ah, entry, mac);
245
246
247		/*
248		 * Write MIC entry according to new or old key layout.
249		 * The MISC_MODE register is assumed already set so
250		 * these writes will be handled properly (happens on
251		 * attach and at every reset).
252		 */
253		/* RX mic */
254		mic0 = LE_READ_4(k->kv_mic+0);
255		mic2 = LE_READ_4(k->kv_mic+4);
256		if (ahp->ah_miscMode & AR_MISC_MODE_MIC_NEW_LOC_ENABLE) {
257			/*
258			 * Both RX and TX mic values can be combined into
259			 * one cache slot entry:
260			 *  8*N + 800         31:0    RX Michael key 0
261			 *  8*N + 804         15:0    TX Michael key 0 [31:16]
262			 *  8*N + 808         31:0    RX Michael key 1
263			 *  8*N + 80C         15:0    TX Michael key 0 [15:0]
264			 *  8*N + 810         31:0    TX Michael key 1
265			 *  8*N + 814         15:0    reserved
266			 *  8*N + 818         31:0    reserved
267			 *  8*N + 81C         14:0    reserved
268			 *                    15      key valid == 0
269			 */
270			/* TX mic */
271			mic1 = LE_READ_2(k->kv_txmic+2) & 0xffff;
272			mic3 = LE_READ_2(k->kv_txmic+0) & 0xffff;
273			mic4 = LE_READ_4(k->kv_txmic+4);
274		} else {
275			mic1 = mic3 = mic4 = 0;
276		}
277		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
278		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), mic1);
279		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
280		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), mic3);
281		OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), mic4);
282		OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
283			AR_KEYTABLE_TYPE_CLR);
284		/* NB: MIC key is not marked valid and has no MAC address */
285		OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(micentry), 0);
286		OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(micentry), 0);
287
288		/* correct intentionally corrupted key */
289		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
290		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
291	} else {
292		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
293		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
294		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
295		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
296		OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
297		OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
298
299		(void) ar5212SetKeyCacheEntryMac(ah, entry, mac);
300	}
301	return AH_TRUE;
302}
303