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
31static const u8 otus_magic[4] = { OTUS_MAGIC };
32
33static 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
52static 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
95static 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
126static 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
135static 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
144static 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
201static 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
218static 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
236static 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
380static struct carl9170fw_desc_head *
381carl9170_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
410int 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