1 /*
2  * Atheros CARL9170 driver
3  *
4  * firmware parser
5  *
6  * Copyright 2009, 2010, Christian Lamparter <chunkeey@googlemail.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; see the file COPYING.  If not, see
20  * http://www.gnu.org/licenses/.
21  */
22 
23 #include <linux/kernel.h>
24 #include <linux/firmware.h>
25 #include <linux/crc32.h>
26 #include <linux/module.h>
27 #include "carl9170.h"
28 #include "fwcmd.h"
29 #include "version.h"
30 
31 static const u8 otus_magic[4] = { OTUS_MAGIC };
32 
33 static const void *carl9170_fw_find_desc(struct ar9170 *ar, const u8 descid[4],
34 	const unsigned int len, const u8 compatible_revision)
35 {
36 	const struct carl9170fw_desc_head *iter;
37 
38 	carl9170fw_for_each_hdr(iter, ar->fw.desc) {
39 		if (carl9170fw_desc_cmp(iter, descid, len,
40 					compatible_revision))
41 			return (void *)iter;
42 	}
43 
44 	/* needed to find the LAST desc */
45 	if (carl9170fw_desc_cmp(iter, descid, len,
46 				compatible_revision))
47 		return (void *)iter;
48 
49 	return NULL;
50 }
51 
52 static int carl9170_fw_verify_descs(struct ar9170 *ar,
53 	const struct carl9170fw_desc_head *head, unsigned int max_len)
54 {
55 	const struct carl9170fw_desc_head *pos;
56 	unsigned long pos_addr, end_addr;
57 	unsigned int pos_length;
58 
59 	if (max_len < sizeof(*pos))
60 		return -ENODATA;
61 
62 	max_len = min_t(unsigned int, CARL9170FW_DESC_MAX_LENGTH, max_len);
63 
64 	pos = head;
65 	pos_addr = (unsigned long) pos;
66 	end_addr = pos_addr + max_len;
67 
68 	while (pos_addr < end_addr) {
69 		if (pos_addr + sizeof(*head) > end_addr)
70 			return -E2BIG;
71 
72 		pos_length = le16_to_cpu(pos->length);
73 
74 		if (pos_length < sizeof(*head))
75 			return -EBADMSG;
76 
77 		if (pos_length > max_len)
78 			return -EOVERFLOW;
79 
80 		if (pos_addr + pos_length > end_addr)
81 			return -EMSGSIZE;
82 
83 		if (carl9170fw_desc_cmp(pos, LAST_MAGIC,
84 					CARL9170FW_LAST_DESC_SIZE,
85 					CARL9170FW_LAST_DESC_CUR_VER))
86 			return 0;
87 
88 		pos_addr += pos_length;
89 		pos = (void *)pos_addr;
90 		max_len -= pos_length;
91 	}
92 	return -EINVAL;
93 }
94 
95 static void carl9170_fw_info(struct ar9170 *ar)
96 {
97 	const struct carl9170fw_motd_desc *motd_desc;
98 	unsigned int str_ver_len;
99 	u32 fw_date;
100 
101 	dev_info(&ar->udev->dev, "driver   API: %s 2%03d-%02d-%02d [%d-%d]\n",
102 		CARL9170FW_VERSION_GIT, CARL9170FW_VERSION_YEAR,
103 		CARL9170FW_VERSION_MONTH, CARL9170FW_VERSION_DAY,
104 		CARL9170FW_API_MIN_VER, CARL9170FW_API_MAX_VER);
105 
106 	motd_desc = carl9170_fw_find_desc(ar, MOTD_MAGIC,
107 		sizeof(*motd_desc), CARL9170FW_MOTD_DESC_CUR_VER);
108 
109 	if (motd_desc) {
110 		str_ver_len = strnlen(motd_desc->release,
111 			CARL9170FW_MOTD_RELEASE_LEN);
112 
113 		fw_date = le32_to_cpu(motd_desc->fw_year_month_day);
114 
115 		dev_info(&ar->udev->dev, "firmware API: %.*s 2%03d-%02d-%02d\n",
116 			 str_ver_len, motd_desc->release,
117 			 CARL9170FW_GET_YEAR(fw_date),
118 			 CARL9170FW_GET_MONTH(fw_date),
119 			 CARL9170FW_GET_DAY(fw_date));
120 
121 		strlcpy(ar->hw->wiphy->fw_version, motd_desc->release,
122 			sizeof(ar->hw->wiphy->fw_version));
123 	}
124 }
125 
126 static bool valid_dma_addr(const u32 address)
127 {
128 	if (address >= AR9170_SRAM_OFFSET &&
129 	    address < (AR9170_SRAM_OFFSET + AR9170_SRAM_SIZE))
130 		return true;
131 
132 	return false;
133 }
134 
135 static bool valid_cpu_addr(const u32 address)
136 {
137 	if (valid_dma_addr(address) || (address >= AR9170_PRAM_OFFSET &&
138 	    address < (AR9170_PRAM_OFFSET + AR9170_PRAM_SIZE)))
139 		return true;
140 
141 	return false;
142 }
143 
144 static int carl9170_fw_checksum(struct ar9170 *ar, const __u8 *data,
145 				size_t len)
146 {
147 	const struct carl9170fw_otus_desc *otus_desc;
148 	const struct carl9170fw_last_desc *last_desc;
149 	const struct carl9170fw_chk_desc *chk_desc;
150 	unsigned long fin, diff;
151 	unsigned int dsc_len;
152 	u32 crc32;
153 
154 	last_desc = carl9170_fw_find_desc(ar, LAST_MAGIC,
155 		sizeof(*last_desc), CARL9170FW_LAST_DESC_CUR_VER);
156 	if (!last_desc)
157 		return -EINVAL;
158 
159 	otus_desc = carl9170_fw_find_desc(ar, OTUS_MAGIC,
160 		sizeof(*otus_desc), CARL9170FW_OTUS_DESC_CUR_VER);
161 	if (!otus_desc) {
162 		dev_err(&ar->udev->dev, "failed to find compatible firmware "
163 			"descriptor.\n");
164 		return -ENODATA;
165 	}
166 
167 	chk_desc = carl9170_fw_find_desc(ar, CHK_MAGIC,
168 		sizeof(*chk_desc), CARL9170FW_CHK_DESC_CUR_VER);
169 
170 	if (!chk_desc) {
171 		dev_warn(&ar->udev->dev, "Unprotected firmware image.\n");
172 		return 0;
173 	}
174 
175 	dsc_len = min_t(unsigned int, len,
176 			(unsigned long)chk_desc - (unsigned long)otus_desc);
177 
178 	fin = (unsigned long) last_desc + sizeof(*last_desc);
179 	diff = fin - (unsigned long) otus_desc;
180 
181 	if (diff < len)
182 		len -= diff;
183 
184 	if (len < 256)
185 		return -EIO;
186 
187 	crc32 = crc32_le(~0, data, len);
188 	if (cpu_to_le32(crc32) != chk_desc->fw_crc32) {
189 		dev_err(&ar->udev->dev, "fw checksum test failed.\n");
190 		return -ENOEXEC;
191 	}
192 
193 	crc32 = crc32_le(crc32, (void *)otus_desc, dsc_len);
194 	if (cpu_to_le32(crc32) != chk_desc->hdr_crc32) {
195 		dev_err(&ar->udev->dev, "descriptor check failed.\n");
196 		return -EINVAL;
197 	}
198 	return 0;
199 }
200 
201 static int carl9170_fw_tx_sequence(struct ar9170 *ar)
202 {
203 	const struct carl9170fw_txsq_desc *txsq_desc;
204 
205 	txsq_desc = carl9170_fw_find_desc(ar, TXSQ_MAGIC, sizeof(*txsq_desc),
206 					  CARL9170FW_TXSQ_DESC_CUR_VER);
207 	if (txsq_desc) {
208 		ar->fw.tx_seq_table = le32_to_cpu(txsq_desc->seq_table_addr);
209 		if (!valid_cpu_addr(ar->fw.tx_seq_table))
210 			return -EINVAL;
211 	} else {
212 		ar->fw.tx_seq_table = 0;
213 	}
214 
215 	return 0;
216 }
217 
218 static void carl9170_fw_set_if_combinations(struct ar9170 *ar,
219 					    u16 if_comb_types)
220 {
221 	if (ar->fw.vif_num < 2)
222 		return;
223 
224 	ar->if_comb_limits[0].max = ar->fw.vif_num;
225 	ar->if_comb_limits[0].types = if_comb_types;
226 
227 	ar->if_combs[0].num_different_channels = 1;
228 	ar->if_combs[0].max_interfaces = ar->fw.vif_num;
229 	ar->if_combs[0].limits = ar->if_comb_limits;
230 	ar->if_combs[0].n_limits = ARRAY_SIZE(ar->if_comb_limits);
231 
232 	ar->hw->wiphy->iface_combinations = ar->if_combs;
233 	ar->hw->wiphy->n_iface_combinations = ARRAY_SIZE(ar->if_combs);
234 }
235 
236 static int carl9170_fw(struct ar9170 *ar, const __u8 *data, size_t len)
237 {
238 	const struct carl9170fw_otus_desc *otus_desc;
239 	int err;
240 	u16 if_comb_types;
241 
242 	err = carl9170_fw_checksum(ar, data, len);
243 	if (err)
244 		return err;
245 
246 	otus_desc = carl9170_fw_find_desc(ar, OTUS_MAGIC,
247 		sizeof(*otus_desc), CARL9170FW_OTUS_DESC_CUR_VER);
248 	if (!otus_desc) {
249 		return -ENODATA;
250 	}
251 
252 #define SUPP(feat)						\
253 	(carl9170fw_supports(otus_desc->feature_set, feat))
254 
255 	if (!SUPP(CARL9170FW_DUMMY_FEATURE)) {
256 		dev_err(&ar->udev->dev, "invalid firmware descriptor "
257 			"format detected.\n");
258 		return -EINVAL;
259 	}
260 
261 	ar->fw.api_version = otus_desc->api_ver;
262 
263 	if (ar->fw.api_version < CARL9170FW_API_MIN_VER ||
264 	    ar->fw.api_version > CARL9170FW_API_MAX_VER) {
265 		dev_err(&ar->udev->dev, "unsupported firmware api version.\n");
266 		return -EINVAL;
267 	}
268 
269 	if (!SUPP(CARL9170FW_COMMAND_PHY) || SUPP(CARL9170FW_UNUSABLE) ||
270 	    !SUPP(CARL9170FW_HANDLE_BACK_REQ)) {
271 		dev_err(&ar->udev->dev, "firmware does support "
272 			"mandatory features.\n");
273 		return -ECANCELED;
274 	}
275 
276 	if (ilog2(le32_to_cpu(otus_desc->feature_set)) >=
277 		__CARL9170FW_FEATURE_NUM) {
278 		dev_warn(&ar->udev->dev, "driver does not support all "
279 			 "firmware features.\n");
280 	}
281 
282 	if (!SUPP(CARL9170FW_COMMAND_CAM)) {
283 		dev_info(&ar->udev->dev, "crypto offloading is disabled "
284 			 "by firmware.\n");
285 		ar->fw.disable_offload_fw = true;
286 	}
287 
288 	if (SUPP(CARL9170FW_PSM) && SUPP(CARL9170FW_FIXED_5GHZ_PSM))
289 		ar->hw->flags |= IEEE80211_HW_SUPPORTS_PS;
290 
291 	if (!SUPP(CARL9170FW_USB_INIT_FIRMWARE)) {
292 		dev_err(&ar->udev->dev, "firmware does not provide "
293 			"mandatory interfaces.\n");
294 		return -EINVAL;
295 	}
296 
297 	if (SUPP(CARL9170FW_MINIBOOT))
298 		ar->fw.offset = le16_to_cpu(otus_desc->miniboot_size);
299 	else
300 		ar->fw.offset = 0;
301 
302 	if (SUPP(CARL9170FW_USB_DOWN_STREAM)) {
303 		ar->hw->extra_tx_headroom += sizeof(struct ar9170_stream);
304 		ar->fw.tx_stream = true;
305 	}
306 
307 	if (SUPP(CARL9170FW_USB_UP_STREAM))
308 		ar->fw.rx_stream = true;
309 
310 	if (SUPP(CARL9170FW_RX_FILTER)) {
311 		ar->fw.rx_filter = true;
312 		ar->rx_filter_caps = FIF_FCSFAIL | FIF_PLCPFAIL |
313 			FIF_CONTROL | FIF_PSPOLL | FIF_OTHER_BSS |
314 			FIF_PROMISC_IN_BSS;
315 	}
316 
317 	if (SUPP(CARL9170FW_HW_COUNTERS))
318 		ar->fw.hw_counters = true;
319 
320 	if (SUPP(CARL9170FW_WOL))
321 		device_set_wakeup_enable(&ar->udev->dev, true);
322 
323 	if (SUPP(CARL9170FW_RX_BA_FILTER))
324 		ar->fw.ba_filter = true;
325 
326 	if_comb_types = BIT(NL80211_IFTYPE_STATION) |
327 			BIT(NL80211_IFTYPE_P2P_CLIENT);
328 
329 	ar->fw.vif_num = otus_desc->vif_num;
330 	ar->fw.cmd_bufs = otus_desc->cmd_bufs;
331 	ar->fw.address = le32_to_cpu(otus_desc->fw_address);
332 	ar->fw.rx_size = le16_to_cpu(otus_desc->rx_max_frame_len);
333 	ar->fw.mem_blocks = min_t(unsigned int, otus_desc->tx_descs, 0xfe);
334 	atomic_set(&ar->mem_free_blocks, ar->fw.mem_blocks);
335 	ar->fw.mem_block_size = le16_to_cpu(otus_desc->tx_frag_len);
336 
337 	if (ar->fw.vif_num >= AR9170_MAX_VIRTUAL_MAC || !ar->fw.vif_num ||
338 	    ar->fw.mem_blocks < 16 || !ar->fw.cmd_bufs ||
339 	    ar->fw.mem_block_size < 64 || ar->fw.mem_block_size > 512 ||
340 	    ar->fw.rx_size > 32768 || ar->fw.rx_size < 4096 ||
341 	    !valid_cpu_addr(ar->fw.address)) {
342 		dev_err(&ar->udev->dev, "firmware shows obvious signs of "
343 			"malicious tampering.\n");
344 		return -EINVAL;
345 	}
346 
347 	ar->fw.beacon_addr = le32_to_cpu(otus_desc->bcn_addr);
348 	ar->fw.beacon_max_len = le16_to_cpu(otus_desc->bcn_len);
349 
350 	if (valid_dma_addr(ar->fw.beacon_addr) && ar->fw.beacon_max_len >=
351 	    AR9170_MAC_BCN_LENGTH_MAX) {
352 		ar->hw->wiphy->interface_modes |= BIT(NL80211_IFTYPE_ADHOC);
353 
354 		if (SUPP(CARL9170FW_WLANTX_CAB)) {
355 			if_comb_types |=
356 				BIT(NL80211_IFTYPE_AP) |
357 				BIT(NL80211_IFTYPE_P2P_GO);
358 
359 #ifdef CONFIG_MAC80211_MESH
360 			if_comb_types |=
361 				BIT(NL80211_IFTYPE_MESH_POINT);
362 #endif /* CONFIG_MAC80211_MESH */
363 		}
364 	}
365 
366 	carl9170_fw_set_if_combinations(ar, if_comb_types);
367 
368 	ar->hw->wiphy->interface_modes |= if_comb_types;
369 
370 	ar->hw->wiphy->flags &= ~WIPHY_FLAG_PS_ON_BY_DEFAULT;
371 
372 	/* As IBSS Encryption is software-based, IBSS RSN is supported. */
373 	ar->hw->wiphy->flags |= WIPHY_FLAG_HAS_REMAIN_ON_CHANNEL |
374 		 WIPHY_FLAG_IBSS_RSN | WIPHY_FLAG_SUPPORTS_TDLS;
375 
376 #undef SUPPORTED
377 	return carl9170_fw_tx_sequence(ar);
378 }
379 
380 static struct carl9170fw_desc_head *
381 carl9170_find_fw_desc(struct ar9170 *ar, const __u8 *fw_data, const size_t len)
382 
383 {
384 	int scan = 0, found = 0;
385 
386 	if (!carl9170fw_size_check(len)) {
387 		dev_err(&ar->udev->dev, "firmware size is out of bound.\n");
388 		return NULL;
389 	}
390 
391 	while (scan < len - sizeof(struct carl9170fw_desc_head)) {
392 		if (fw_data[scan++] == otus_magic[found])
393 			found++;
394 		else
395 			found = 0;
396 
397 		if (scan >= len)
398 			break;
399 
400 		if (found == sizeof(otus_magic))
401 			break;
402 	}
403 
404 	if (found != sizeof(otus_magic))
405 		return NULL;
406 
407 	return (void *)&fw_data[scan - found];
408 }
409 
410 int carl9170_parse_firmware(struct ar9170 *ar)
411 {
412 	const struct carl9170fw_desc_head *fw_desc = NULL;
413 	const struct firmware *fw = ar->fw.fw;
414 	unsigned long header_offset = 0;
415 	int err;
416 
417 	if (WARN_ON(!fw))
418 		return -EINVAL;
419 
420 	fw_desc = carl9170_find_fw_desc(ar, fw->data, fw->size);
421 
422 	if (!fw_desc) {
423 		dev_err(&ar->udev->dev, "unsupported firmware.\n");
424 		return -ENODATA;
425 	}
426 
427 	header_offset = (unsigned long)fw_desc - (unsigned long)fw->data;
428 
429 	err = carl9170_fw_verify_descs(ar, fw_desc, fw->size - header_offset);
430 	if (err) {
431 		dev_err(&ar->udev->dev, "damaged firmware (%d).\n", err);
432 		return err;
433 	}
434 
435 	ar->fw.desc = fw_desc;
436 
437 	carl9170_fw_info(ar);
438 
439 	err = carl9170_fw(ar, fw->data, fw->size);
440 	if (err) {
441 		dev_err(&ar->udev->dev, "failed to parse firmware (%d).\n",
442 			err);
443 		return err;
444 	}
445 
446 	return 0;
447 }
448