xref: /freebsd/sys/dev/ath/ath_hal/ar5210/ar5210_keycache.c (revision aa24f48b361effe51163877d84f1b70d32b77e04)
1 /*
2  * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
3  * Copyright (c) 2002-2004 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 "ar5210/ar5210.h"
25 #include "ar5210/ar5210reg.h"
26 
27 #define	AR_KEYTABLE_SIZE	64
28 #define	KEY_XOR			0xaa
29 
30 /*
31  * Return the size of the hardware key cache.
32  */
33 u_int
34 ar5210GetKeyCacheSize(struct ath_hal *ah)
35 {
36 	return AR_KEYTABLE_SIZE;
37 }
38 
39 /*
40  * Return the size of the hardware key cache.
41  */
42 HAL_BOOL
43 ar5210IsKeyCacheEntryValid(struct ath_hal *ah, uint16_t entry)
44 {
45 	if (entry < AR_KEYTABLE_SIZE) {
46 		uint32_t val = OS_REG_READ(ah, AR_KEYTABLE_MAC1(entry));
47 		if (val & AR_KEYTABLE_VALID)
48 			return AH_TRUE;
49 	}
50 	return AH_FALSE;
51 }
52 
53 /*
54  * Clear the specified key cache entry.
55  */
56 HAL_BOOL
57 ar5210ResetKeyCacheEntry(struct ath_hal *ah, uint16_t entry)
58 {
59 	if (entry < AR_KEYTABLE_SIZE) {
60 		OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), 0);
61 		OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), 0);
62 		OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), 0);
63 		OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), 0);
64 		OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), 0);
65 		OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), 0);
66 		OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), 0);
67 		OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry), 0);
68 		return AH_TRUE;
69 	}
70 	return AH_FALSE;
71 }
72 
73 /*
74  * Sets the mac part of the specified key cache entry and mark it valid.
75  */
76 HAL_BOOL
77 ar5210SetKeyCacheEntryMac(struct ath_hal *ah, uint16_t entry, const uint8_t *mac)
78 {
79 	uint32_t macHi, macLo;
80 
81 	if (entry < AR_KEYTABLE_SIZE) {
82 		/*
83 		 * Set MAC address -- shifted right by 1.  MacLo is
84 		 * the 4 MSBs, and MacHi is the 2 LSBs.
85 		 */
86 		if (mac != AH_NULL) {
87 			macHi = (mac[5] << 8) | mac[4];
88 			macLo = (mac[3] << 24)| (mac[2] << 16)
89 			      | (mac[1] << 8) | mac[0];
90 			macLo >>= 1;
91 			macLo |= (macHi & 1) << 31;	/* carry */
92 			macHi >>= 1;
93 		} else {
94 			macLo = macHi = 0;
95 		}
96 
97 		OS_REG_WRITE(ah, AR_KEYTABLE_MAC0(entry), macLo);
98 		OS_REG_WRITE(ah, AR_KEYTABLE_MAC1(entry),
99 			macHi | AR_KEYTABLE_VALID);
100 		return AH_TRUE;
101 	}
102 	return AH_FALSE;
103 }
104 
105 /*
106  * Sets the contents of the specified key cache entry.
107  */
108 HAL_BOOL
109 ar5210SetKeyCacheEntry(struct ath_hal *ah, uint16_t entry,
110                        const HAL_KEYVAL *k, const uint8_t *mac, int xorKey)
111 {
112 	uint32_t key0, key1, key2, key3, key4;
113 	uint32_t keyType;
114 	uint32_t xorMask= xorKey ?
115 		(KEY_XOR << 24 | KEY_XOR << 16 | KEY_XOR << 8 | KEY_XOR) : 0;
116 
117 	if (entry >= AR_KEYTABLE_SIZE)
118 		return AH_FALSE;
119 	if (k->kv_type != HAL_CIPHER_WEP) {
120 		HALDEBUG(ah, HAL_DEBUG_ANY, "%s: cipher %u not supported\n",
121 		    __func__, k->kv_type);
122 		return AH_FALSE;
123 	}
124 
125 	/* NB: only WEP supported */
126 	if (k->kv_len < 40 / NBBY)
127 		return AH_FALSE;
128 	if (k->kv_len <= 40 / NBBY)
129 		keyType = AR_KEYTABLE_TYPE_40;
130 	else if (k->kv_len <= 104 / NBBY)
131 		keyType = AR_KEYTABLE_TYPE_104;
132 	else
133 		keyType = AR_KEYTABLE_TYPE_128;
134 
135 	key0 = LE_READ_4(k->kv_val+0) ^ xorMask;
136 	key1 = (LE_READ_2(k->kv_val+4) ^ xorMask) & 0xffff;
137 	key2 = LE_READ_4(k->kv_val+6) ^ xorMask;
138 	key3 = (LE_READ_2(k->kv_val+10) ^ xorMask) & 0xffff;
139 	key4 = LE_READ_4(k->kv_val+12) ^ xorMask;
140 	if (k->kv_len <= 104 / NBBY)
141 		key4 &= 0xff;
142 
143 	/*
144 	 * Note: WEP key cache hardware requires that each double-word
145 	 * pair be written in even/odd order (since the destination is
146 	 * a 64-bit register).  Don't reorder these writes w/o
147 	 * understanding this!
148 	 */
149 	OS_REG_WRITE(ah, AR_KEYTABLE_KEY0(entry), key0);
150 	OS_REG_WRITE(ah, AR_KEYTABLE_KEY1(entry), key1);
151 	OS_REG_WRITE(ah, AR_KEYTABLE_KEY2(entry), key2);
152 	OS_REG_WRITE(ah, AR_KEYTABLE_KEY3(entry), key3);
153 	OS_REG_WRITE(ah, AR_KEYTABLE_KEY4(entry), key4);
154 	OS_REG_WRITE(ah, AR_KEYTABLE_TYPE(entry), keyType);
155 	return ar5210SetKeyCacheEntryMac(ah, entry, mac);
156 }
157