1/*
2 * Ultra Wide Band
3 * Address management
4 *
5 * Copyright (C) 2005-2006 Intel Corporation
6 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version
10 * 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 * 02110-1301, USA.
21 *
22 *
23 * FIXME: docs
24 */
25
26#include <linux/slab.h>
27#include <linux/errno.h>
28#include <linux/module.h>
29#include <linux/device.h>
30#include <linux/random.h>
31#include <linux/etherdevice.h>
32
33#include "uwb-internal.h"
34
35
36/** Device Address Management command */
37struct uwb_rc_cmd_dev_addr_mgmt {
38 struct uwb_rccb rccb;
39 u8 bmOperationType;
40 u8 baAddr[6];
41} __attribute__((packed));
42
43
44/**
45 * Low level command for setting/getting UWB radio's addresses
46 *
47 * @hwarc: HWA Radio Control interface instance
48 * @bmOperationType:
49 * Set/get, MAC/DEV (see WUSB1.0[8.6.2.2])
50 * @baAddr: address buffer--assumed to have enough data to hold
51 * the address type requested.
52 * @reply: Pointer to reply buffer (can be stack allocated)
53 * @returns: 0 if ok, < 0 errno code on error.
54 *
55 * @cmd has to be allocated because USB cannot grok USB or vmalloc
56 * buffers depending on your combination of host architecture.
57 */
58static
59int uwb_rc_dev_addr_mgmt(struct uwb_rc *rc,
60 u8 bmOperationType, const u8 *baAddr,
61 struct uwb_rc_evt_dev_addr_mgmt *reply)
62{
63 int result;
64 struct uwb_rc_cmd_dev_addr_mgmt *cmd;
65
66 result = -ENOMEM;
67 cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
68 if (cmd == NULL)
69 goto error_kzalloc;
70 cmd->rccb.bCommandType = UWB_RC_CET_GENERAL;
71 cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_DEV_ADDR_MGMT);
72 cmd->bmOperationType = bmOperationType;
73 if (baAddr) {
74 size_t size = 0;
75 switch (bmOperationType >> 1) {
76 case 0: size = 2; break;
77 case 1: size = 6; break;
78 default: BUG();
79 }
80 memcpy(cmd->baAddr, baAddr, size);
81 }
82 reply->rceb.bEventType = UWB_RC_CET_GENERAL;
83 reply->rceb.wEvent = UWB_RC_CMD_DEV_ADDR_MGMT;
84 result = uwb_rc_cmd(rc, "DEV-ADDR-MGMT",
85 &cmd->rccb, sizeof(*cmd),
86 &reply->rceb, sizeof(*reply));
87 if (result < 0)
88 goto error_cmd;
89 if (result < sizeof(*reply)) {
90 dev_err(&rc->uwb_dev.dev,
91 "DEV-ADDR-MGMT: not enough data replied: "
92 "%d vs %zu bytes needed\n", result, sizeof(*reply));
93 result = -ENOMSG;
94 } else if (reply->bResultCode != UWB_RC_RES_SUCCESS) {
95 dev_err(&rc->uwb_dev.dev,
96 "DEV-ADDR-MGMT: command execution failed: %s (%d)\n",
97 uwb_rc_strerror(reply->bResultCode),
98 reply->bResultCode);
99 result = -EIO;
100 } else
101 result = 0;
102error_cmd:
103 kfree(cmd);
104error_kzalloc:
105 return result;
106}
107
108
109/**
110 * Set the UWB RC MAC or device address.
111 *
112 * @rc: UWB Radio Controller
113 * @_addr: Pointer to address to write [assumed to be either a
114 * 'struct uwb_mac_addr *' or a 'struct uwb_dev_addr *'].
115 * @type: Type of address to set (UWB_ADDR_DEV or UWB_ADDR_MAC).
116 * @returns: 0 if ok, < 0 errno code on error.
117 *
118 * Some anal retentivity here: even if both 'struct
119 * uwb_{dev,mac}_addr' have the actual byte array in the same offset
120 * and I could just pass _addr to hwarc_cmd_dev_addr_mgmt(), I prefer
121 * to use some syntatic sugar in case someday we decide to change the
122 * format of the structs. The compiler will optimize it out anyway.
123 */
124static int uwb_rc_addr_set(struct uwb_rc *rc,
125 const void *_addr, enum uwb_addr_type type)
126{
127 int result;
128 u8 bmOperationType = 0x1; /* Set address */
129 const struct uwb_dev_addr *dev_addr = _addr;
130 const struct uwb_mac_addr *mac_addr = _addr;
131 struct uwb_rc_evt_dev_addr_mgmt reply;
132 const u8 *baAddr;
133
134 result = -EINVAL;
135 switch (type) {
136 case UWB_ADDR_DEV:
137 baAddr = dev_addr->data;
138 break;
139 case UWB_ADDR_MAC:
140 baAddr = mac_addr->data;
141 bmOperationType |= 0x2;
142 break;
143 default:
144 return result;
145 }
146 return uwb_rc_dev_addr_mgmt(rc, bmOperationType, baAddr, &reply);
147}
148
149
150/**
151 * Get the UWB radio's MAC or device address.
152 *
153 * @rc: UWB Radio Controller
154 * @_addr: Where to write the address data [assumed to be either a
155 * 'struct uwb_mac_addr *' or a 'struct uwb_dev_addr *'].
156 * @type: Type of address to get (UWB_ADDR_DEV or UWB_ADDR_MAC).
157 * @returns: 0 if ok (and *_addr set), < 0 errno code on error.
158 *
159 * See comment in uwb_rc_addr_set() about anal retentivity in the
160 * type handling of the address variables.
161 */
162static int uwb_rc_addr_get(struct uwb_rc *rc,
163 void *_addr, enum uwb_addr_type type)
164{
165 int result;
166 u8 bmOperationType = 0x0; /* Get address */
167 struct uwb_rc_evt_dev_addr_mgmt evt;
168 struct uwb_dev_addr *dev_addr = _addr;
169 struct uwb_mac_addr *mac_addr = _addr;
170 u8 *baAddr;
171
172 result = -EINVAL;
173 switch (type) {
174 case UWB_ADDR_DEV:
175 baAddr = dev_addr->data;
176 break;
177 case UWB_ADDR_MAC:
178 bmOperationType |= 0x2;
179 baAddr = mac_addr->data;
180 break;
181 default:
182 return result;
183 }
184 result = uwb_rc_dev_addr_mgmt(rc, bmOperationType, baAddr, &evt);
185 if (result == 0)
186 switch (type) {
187 case UWB_ADDR_DEV:
188 memcpy(&dev_addr->data, evt.baAddr,
189 sizeof(dev_addr->data));
190 break;
191 case UWB_ADDR_MAC:
192 memcpy(&mac_addr->data, evt.baAddr,
193 sizeof(mac_addr->data));
194 break;
195 default: /* shut gcc up */
196 BUG();
197 }
198 return result;
199}
200
201
202/** Get @rc's MAC address to @addr */
203int uwb_rc_mac_addr_get(struct uwb_rc *rc,
204 struct uwb_mac_addr *addr) {
205 return uwb_rc_addr_get(rc, addr, UWB_ADDR_MAC);
206}
207EXPORT_SYMBOL_GPL(uwb_rc_mac_addr_get);
208
209
210/** Get @rc's device address to @addr */
211int uwb_rc_dev_addr_get(struct uwb_rc *rc,
212 struct uwb_dev_addr *addr) {
213 return uwb_rc_addr_get(rc, addr, UWB_ADDR_DEV);
214}
215EXPORT_SYMBOL_GPL(uwb_rc_dev_addr_get);
216
217
218/** Set @rc's address to @addr */
219int uwb_rc_mac_addr_set(struct uwb_rc *rc,
220 const struct uwb_mac_addr *addr)
221{
222 int result = -EINVAL;
223 mutex_lock(&rc->uwb_dev.mutex);
224 result = uwb_rc_addr_set(rc, addr, UWB_ADDR_MAC);
225 mutex_unlock(&rc->uwb_dev.mutex);
226 return result;
227}
228
229
230/** Set @rc's address to @addr */
231int uwb_rc_dev_addr_set(struct uwb_rc *rc,
232 const struct uwb_dev_addr *addr)
233{
234 int result = -EINVAL;
235 mutex_lock(&rc->uwb_dev.mutex);
236 result = uwb_rc_addr_set(rc, addr, UWB_ADDR_DEV);
237 rc->uwb_dev.dev_addr = *addr;
238 mutex_unlock(&rc->uwb_dev.mutex);
239 return result;
240}
241
242/* Returns !0 if given address is already assigned to device. */
243int __uwb_mac_addr_assigned_check(struct device *dev, void *_addr)
244{
245 struct uwb_dev *uwb_dev = to_uwb_dev(dev);
246 struct uwb_mac_addr *addr = _addr;
247
248 if (!uwb_mac_addr_cmp(addr, &uwb_dev->mac_addr))
249 return !0;
250 return 0;
251}
252
253/* Returns !0 if given address is already assigned to device. */
254int __uwb_dev_addr_assigned_check(struct device *dev, void *_addr)
255{
256 struct uwb_dev *uwb_dev = to_uwb_dev(dev);
257 struct uwb_dev_addr *addr = _addr;
258 if (!uwb_dev_addr_cmp(addr, &uwb_dev->dev_addr))
259 return !0;
260 return 0;
261}
262
263/**
264 * uwb_dev_addr_assign - assigned a generated DevAddr to a radio controller
265 * @rc: the (local) radio controller device requiring a new DevAddr
266 *
267 * A new DevAddr is required when:
268 * - first setting up a radio controller
269 * - if the hardware reports a DevAddr conflict
270 *
271 * The DevAddr is randomly generated in the generated DevAddr range
272 * [0x100, 0xfeff]. The number of devices in a beacon group is limited
273 * by mMaxBPLength (96) so this address space will never be exhausted.
274 *
275 * [ECMA-368] 17.1.1, 17.16.
276 */
277int uwb_rc_dev_addr_assign(struct uwb_rc *rc)
278{
279 struct uwb_dev_addr new_addr;
280
281 do {
282 get_random_bytes(new_addr.data, sizeof(new_addr.data));
283 } while (new_addr.data[0] == 0x00 || new_addr.data[0] == 0xff
284 || __uwb_dev_addr_assigned(rc, &new_addr));
285
286 return uwb_rc_dev_addr_set(rc, &new_addr);
287}
288
289/**
290 * uwbd_evt_handle_rc_dev_addr_conflict - handle a DEV_ADDR_CONFLICT event
291 * @evt: the DEV_ADDR_CONFLICT notification from the radio controller
292 *
293 * A new (non-conflicting) DevAddr is assigned to the radio controller.
294 *
295 * [ECMA-368] 17.1.1.1.
296 */
297int uwbd_evt_handle_rc_dev_addr_conflict(struct uwb_event *evt)
298{
299 struct uwb_rc *rc = evt->rc;
300
301 return uwb_rc_dev_addr_assign(rc);
302}
303
304/*
305 * Print the 48-bit EUI MAC address of the radio controller when
306 * reading /sys/class/uwb_rc/XX/mac_address
307 */
308static ssize_t uwb_rc_mac_addr_show(struct device *dev,
309 struct device_attribute *attr, char *buf)
310{
311 struct uwb_dev *uwb_dev = to_uwb_dev(dev);
312 struct uwb_rc *rc = uwb_dev->rc;
313 struct uwb_mac_addr addr;
314 ssize_t result;
315
316 mutex_lock(&rc->uwb_dev.mutex);
317 result = uwb_rc_addr_get(rc, &addr, UWB_ADDR_MAC);
318 mutex_unlock(&rc->uwb_dev.mutex);
319 if (result >= 0) {
320 result = uwb_mac_addr_print(buf, UWB_ADDR_STRSIZE, &addr);
321 buf[result++] = '\n';
322 }
323 return result;
324}
325
326/*
327 * Parse a 48 bit address written to /sys/class/uwb_rc/XX/mac_address
328 * and if correct, set it.
329 */
330static ssize_t uwb_rc_mac_addr_store(struct device *dev,
331 struct device_attribute *attr,
332 const char *buf, size_t size)
333{
334 struct uwb_dev *uwb_dev = to_uwb_dev(dev);
335 struct uwb_rc *rc = uwb_dev->rc;
336 struct uwb_mac_addr addr;
337 ssize_t result;
338
339 if (!mac_pton(buf, addr.data))
340 return -EINVAL;
341 if (is_multicast_ether_addr(addr.data)) {
342 dev_err(&rc->uwb_dev.dev, "refusing to set multicast "
343 "MAC address %s\n", buf);
344 return -EINVAL;
345 }
346 result = uwb_rc_mac_addr_set(rc, &addr);
347 if (result == 0)
348 rc->uwb_dev.mac_addr = addr;
349
350 return result < 0 ? result : size;
351}
352DEVICE_ATTR(mac_address, S_IRUGO | S_IWUSR, uwb_rc_mac_addr_show, uwb_rc_mac_addr_store);
353
354/** Print @addr to @buf, @return bytes written */
355size_t __uwb_addr_print(char *buf, size_t buf_size, const unsigned char *addr,
356 int type)
357{
358 size_t result;
359 if (type)
360 result = scnprintf(buf, buf_size, "%pM", addr);
361 else
362 result = scnprintf(buf, buf_size, "%02x:%02x",
363 addr[1], addr[0]);
364 return result;
365}
366EXPORT_SYMBOL_GPL(__uwb_addr_print);
367