1/*-
2 * SPDX-License-Identifier: ISC
3 *
4 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
5 * Copyright (c) 2002-2008 Atheros Communications, Inc.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 *
19 * $FreeBSD: releng/12.0/sys/dev/ath/ath_hal/ar5212/ar5212_keycache.c 326695 2017-12-08 15:57:29Z pfg $
20 */
21#include "opt_ah.h"
22
23#include "ah.h"
24#include "ah_internal.h"
25
26#include "ar5212/ar5212.h"
27#include "ar5212/ar5212reg.h"
28#include "ar5212/ar5212desc.h"
29
30/*
31 * Note: The key cache hardware requires that each double-word
32 * pair be written in even/odd order (since the destination is
33 * a 64-bit register).  Don't reorder the writes in this code
34 * w/o considering this!
35 */
36#define	KEY_XOR			0xaa
37
38#define	IS_MIC_ENABLED(ah) \
39	(AH5212(ah)->ah_staId1Defaults & AR_STA_ID1_CRPT_MIC_ENABLE)
40
41/*
42 * Return the size of the hardware key cache.
43 */
44uint32_t
45ar5212GetKeyCacheSize(struct ath_hal *ah)
46{
47	return AH_PRIVATE(ah)->ah_caps.halKeyCacheSize;
48}
49
50/*
51 * Return true if the specific key cache entry is valid.
52 */
53HAL_BOOL
54ar5212IsKeyCacheEntryValid(struct ath_hal *ah, uint16_t entry)
55{
56	if (entry < AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
57		uint32_t val = OS_REG_READ(ah, AR_KEYTABLE_MAC1(entry));
58		if (val & AR_KEYTABLE_VALID)
59			return AH_TRUE;
60	}
61	return AH_FALSE;
62}
63
64/*
65 * Clear the specified key cache entry and any associated MIC entry.
66 */
67HAL_BOOL
68ar5212ResetKeyCacheEntry(struct ath_hal *ah, uint16_t entry)
69{
70	uint32_t keyType;
71
72	if (entry >= AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
73		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
74		    __func__, entry);
75		return AH_FALSE;
76	}
77	keyType = OS_REG_READ(ah, AR_KEYTABLE_TYPE(entry));
78
79	/* XXX why not clear key type/valid bit first? */
80	OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0);
81	OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0);
82	OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0);
83	OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0);
84	OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0);
85	OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), AR_KEYTABLE_TYPE_CLR);
86	OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0);
87	OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0);
88	if (keyType == AR_KEYTABLE_TYPE_TKIP && IS_MIC_ENABLED(ah)) {
89		uint16_t micentry = entry+64;	/* MIC goes at slot+64 */
90
91		HALASSERT(micentry < AH_PRIVATE(ah)->ah_caps.halKeyCacheSize);
92		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), 0);
93		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), 0);
94		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), 0);
95		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), 0);
96		/* NB: key type and MAC are known to be ok */
97	}
98	return AH_TRUE;
99}
100
101/*
102 * Sets the mac part of the specified key cache entry (and any
103 * associated MIC entry) and mark them valid.
104 *
105 * Since mac[0] is shifted off and not presented to the hardware,
106 * it does double duty as a "don't use for unicast, use for multicast
107 * matching" flag. This interface should later be extended to
108 * explicitly do that rather than overloading a bit in the MAC
109 * address.
110 */
111HAL_BOOL
112ar5212SetKeyCacheEntryMac(struct ath_hal *ah, uint16_t entry, const uint8_t *mac)
113{
114	uint32_t macHi, macLo;
115	uint32_t unicast_flag = AR_KEYTABLE_VALID;
116
117	if (entry >= AH_PRIVATE(ah)->ah_caps.halKeyCacheSize) {
118		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
119		    __func__, entry);
120		return AH_FALSE;
121	}
122	/*
123	 * Set MAC address -- shifted right by 1.  MacLo is
124	 * the 4 MSBs, and MacHi is the 2 LSBs.
125	 */
126	if (mac != AH_NULL) {
127		/*
128		 * AR_KEYTABLE_VALID indicates that the address is a unicast
129		 * address, which must match the transmitter address for
130		 * decrypting frames.
131		 * Not setting this bit allows the hardware to use the key
132		 * for multicast frame decryption.
133		 */
134		if (mac[0] & 0x01)
135			unicast_flag = 0;
136
137		macHi = (mac[5] << 8) | mac[4];
138		macLo = (mac[3] << 24)| (mac[2] << 16)
139		      | (mac[1] << 8) | mac[0];
140		macLo >>= 1;
141		macLo |= (macHi & 1) << 31;	/* carry */
142		macHi >>= 1;
143	} else {
144		macLo = macHi = 0;
145	}
146	OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
147	OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), macHi | unicast_flag);
148	return AH_TRUE;
149}
150
151/*
152 * Sets the contents of the specified key cache entry
153 * and any associated MIC entry.
154 */
155HAL_BOOL
156ar5212SetKeyCacheEntry(struct ath_hal *ah, uint16_t entry,
157                       const HAL_KEYVAL *k, const uint8_t *mac,
158                       int xorKey)
159{
160	struct ath_hal_5212 *ahp = AH5212(ah);
161	const HAL_CAPABILITIES *pCap = &AH_PRIVATE(ah)->ah_caps;
162	uint32_t key0, key1, key2, key3, key4;
163	uint32_t keyType;
164	uint32_t xorMask = xorKey ?
165		(KEY_XOR << 24 | KEY_XOR << 16 | KEY_XOR << 8 | KEY_XOR) : 0;
166
167	if (entry >= pCap->halKeyCacheSize) {
168		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: entry %u out of range\n",
169		    __func__, entry);
170		return AH_FALSE;
171	}
172	switch (k->kv_type) {
173	case HAL_CIPHER_AES_OCB:
174		keyType = AR_KEYTABLE_TYPE_AES;
175		break;
176	case HAL_CIPHER_AES_CCM:
177		if (!pCap->halCipherAesCcmSupport) {
178			HALDEBUG(ah, HAL_DEBUG_ANY,
179			    "%s: AES-CCM not supported by mac rev 0x%x\n",
180			    __func__, AH_PRIVATE(ah)->ah_macRev);
181			return AH_FALSE;
182		}
183		keyType = AR_KEYTABLE_TYPE_CCM;
184		break;
185	case HAL_CIPHER_TKIP:
186		keyType = AR_KEYTABLE_TYPE_TKIP;
187		if (IS_MIC_ENABLED(ah) && entry+64 >= pCap->halKeyCacheSize) {
188			HALDEBUG(ah, HAL_DEBUG_ANY,
189			    "%s: entry %u inappropriate for TKIP\n",
190			    __func__, entry);
191			return AH_FALSE;
192		}
193		break;
194	case HAL_CIPHER_WEP:
195		if (k->kv_len < 40 / NBBY) {
196			HALDEBUG(ah, HAL_DEBUG_ANY,
197			    "%s: WEP key length %u too small\n",
198			    __func__, k->kv_len);
199			return AH_FALSE;
200		}
201		if (k->kv_len <= 40 / NBBY)
202			keyType = AR_KEYTABLE_TYPE_40;
203		else if (k->kv_len <= 104 / NBBY)
204			keyType = AR_KEYTABLE_TYPE_104;
205		else
206			keyType = AR_KEYTABLE_TYPE_128;
207		break;
208	case HAL_CIPHER_CLR:
209		keyType = AR_KEYTABLE_TYPE_CLR;
210		break;
211	default:
212		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: cipher %u not supported\n",
213		    __func__, k->kv_type);
214		return AH_FALSE;
215	}
216
217	key0 = LE_READ_4(k->kv_val+0) ^ xorMask;
218	key1 = (LE_READ_2(k->kv_val+4) ^ xorMask) & 0xffff;
219	key2 = LE_READ_4(k->kv_val+6) ^ xorMask;
220	key3 = (LE_READ_2(k->kv_val+10) ^ xorMask) & 0xffff;
221	key4 = LE_READ_4(k->kv_val+12) ^ xorMask;
222	if (k->kv_len <= 104 / NBBY)
223		key4 &= 0xff;
224
225	/*
226	 * Note: key cache hardware requires that each double-word
227	 * pair be written in even/odd order (since the destination is
228	 * a 64-bit register).  Don't reorder these writes w/o
229	 * considering this!
230	 */
231	if (keyType == AR_KEYTABLE_TYPE_TKIP && IS_MIC_ENABLED(ah)) {
232		uint16_t micentry = entry+64;	/* MIC goes at slot+64 */
233		uint32_t mic0, mic1, mic2, mic3, mic4;
234
235		/*
236		 * Invalidate the encrypt/decrypt key until the MIC
237		 * key is installed so pending rx frames will fail
238		 * with decrypt errors rather than a MIC error.
239		 */
240		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), ~key0);
241		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), ~key1);
242		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
243		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
244		OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
245		OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
246		(void) ar5212SetKeyCacheEntryMac(ah, entry, mac);
247
248		/*
249		 * Write MIC entry according to new or old key layout.
250		 * The MISC_MODE register is assumed already set so
251		 * these writes will be handled properly (happens on
252		 * attach and at every reset).
253		 */
254		/* RX mic */
255		mic0 = LE_READ_4(k->kv_mic+0);
256		mic2 = LE_READ_4(k->kv_mic+4);
257		if (ahp->ah_miscMode & AR_MISC_MODE_MIC_NEW_LOC_ENABLE) {
258			/*
259			 * Both RX and TX mic values can be combined into
260			 * one cache slot entry:
261			 *  8*N + 800         31:0    RX Michael key 0
262			 *  8*N + 804         15:0    TX Michael key 0 [31:16]
263			 *  8*N + 808         31:0    RX Michael key 1
264			 *  8*N + 80C         15:0    TX Michael key 0 [15:0]
265			 *  8*N + 810         31:0    TX Michael key 1
266			 *  8*N + 814         15:0    reserved
267			 *  8*N + 818         31:0    reserved
268			 *  8*N + 81C         14:0    reserved
269			 *                    15      key valid == 0
270			 */
271			/* TX mic */
272			mic1 = LE_READ_2(k->kv_txmic+2) & 0xffff;
273			mic3 = LE_READ_2(k->kv_txmic+0) & 0xffff;
274			mic4 = LE_READ_4(k->kv_txmic+4);
275		} else {
276			mic1 = mic3 = mic4 = 0;
277		}
278		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(micentry), mic0);
279		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(micentry), mic1);
280		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(micentry), mic2);
281		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(micentry), mic3);
282		OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(micentry), mic4);
283		OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(micentry),
284			AR_KEYTABLE_TYPE_CLR);
285		/* NB: MIC key is not marked valid and has no MAC address */
286		OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(micentry), 0);
287		OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(micentry), 0);
288
289		/* correct intentionally corrupted key */
290		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
291		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
292	} else {
293		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
294		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
295		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
296		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
297		OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
298		OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
299
300		(void) ar5212SetKeyCacheEntryMac(ah, entry, mac);
301	}
302	return AH_TRUE;
303}
304