wifi.c revision 243af8b84968ec4f5afb628c43a2c541c4feee7b 
1/*
2 * Copyright 2008, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdlib.h>
18#include <fcntl.h>
19#include <errno.h>
20#include <string.h>
21
22#include "hardware_legacy/wifi.h"
23#include "libwpa_client/wpa_ctrl.h"
24
25#define LOG_TAG "WifiHW"
26#include "cutils/log.h"
27#include "cutils/memory.h"
28#include "cutils/misc.h"
29#include "cutils/properties.h"
30#include "private/android_filesystem_config.h"
31#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
32#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
33#include <sys/_system_properties.h>
34#endif
35
36static struct wpa_ctrl *ctrl_conn;
37static struct wpa_ctrl *monitor_conn;
38
39extern int do_dhcp();
40extern int ifc_init();
41extern void ifc_close();
42extern char *dhcp_lasterror();
43extern void get_dhcp_info();
44extern int init_module(void *, unsigned long, const char *);
45extern int delete_module(const char *, unsigned int);
46
47static char iface[PROPERTY_VALUE_MAX];
48// TODO: use new ANDROID_SOCKET mechanism, once support for multiple
49// sockets is in
50
51#ifndef WIFI_DRIVER_MODULE_PATH
52#define WIFI_DRIVER_MODULE_PATH         "/system/lib/modules/wlan.ko"
53#endif
54#ifndef WIFI_DRIVER_MODULE_NAME
55#define WIFI_DRIVER_MODULE_NAME         "wlan"
56#endif
57#ifndef WIFI_DRIVER_MODULE_ARG
58#define WIFI_DRIVER_MODULE_ARG          ""
59#endif
60#ifndef WIFI_FIRMWARE_LOADER
61#define WIFI_FIRMWARE_LOADER		""
62#endif
63#define WIFI_TEST_INTERFACE		"sta"
64
65static const char IFACE_DIR[]           = "/data/system/wpa_supplicant";
66static const char DRIVER_MODULE_NAME[]  = WIFI_DRIVER_MODULE_NAME;
67static const char DRIVER_MODULE_TAG[]   = WIFI_DRIVER_MODULE_NAME " ";
68static const char DRIVER_MODULE_PATH[]  = WIFI_DRIVER_MODULE_PATH;
69static const char DRIVER_MODULE_ARG[]   = WIFI_DRIVER_MODULE_ARG;
70static const char FIRMWARE_LOADER[]     = WIFI_FIRMWARE_LOADER;
71static const char DRIVER_PROP_NAME[]    = "wlan.driver.status";
72static const char SUPPLICANT_NAME[]     = "wpa_supplicant";
73static const char SUPP_PROP_NAME[]      = "init.svc.wpa_supplicant";
74static const char SUPP_CONFIG_TEMPLATE[]= "/system/etc/wifi/wpa_supplicant.conf";
75static const char SUPP_CONFIG_FILE[]    = "/data/misc/wifi/wpa_supplicant.conf";
76static const char MODULE_FILE[]         = "/proc/modules";
77
78static int insmod(const char *filename, const char *args)
79{
80    void *module;
81    unsigned int size;
82    int ret;
83
84    module = load_file(filename, &size);
85    if (!module)
86        return -1;
87
88    ret = init_module(module, size, args);
89
90    free(module);
91
92    return ret;
93}
94
95static int rmmod(const char *modname)
96{
97    int ret = -1;
98    int maxtry = 10;
99
100    while (maxtry-- > 0) {
101        ret = delete_module(modname, O_NONBLOCK | O_EXCL);
102        if (ret < 0 && errno == EAGAIN)
103            usleep(500000);
104        else
105            break;
106    }
107
108    if (ret != 0)
109        LOGD("Unable to unload driver module \"%s\": %s\n",
110             modname, strerror(errno));
111    return ret;
112}
113
114int do_dhcp_request(int *ipaddr, int *gateway, int *mask,
115                    int *dns1, int *dns2, int *server, int *lease) {
116    /* For test driver, always report success */
117    if (strcmp(iface, WIFI_TEST_INTERFACE) == 0)
118        return 0;
119
120    if (ifc_init() < 0)
121        return -1;
122
123    if (do_dhcp(iface) < 0) {
124        ifc_close();
125        return -1;
126    }
127    ifc_close();
128    get_dhcp_info(ipaddr, gateway, mask, dns1, dns2, server, lease);
129    return 0;
130}
131
132const char *get_dhcp_error_string() {
133    return dhcp_lasterror();
134}
135
136static int check_driver_loaded() {
137    char driver_status[PROPERTY_VALUE_MAX];
138    FILE *proc;
139    char line[sizeof(DRIVER_MODULE_TAG)+10];
140
141    if (!property_get(DRIVER_PROP_NAME, driver_status, NULL)
142            || strcmp(driver_status, "ok") != 0) {
143        return 0;  /* driver not loaded */
144    }
145    /*
146     * If the property says the driver is loaded, check to
147     * make sure that the property setting isn't just left
148     * over from a previous manual shutdown or a runtime
149     * crash.
150     */
151    if ((proc = fopen(MODULE_FILE, "r")) == NULL) {
152        LOGW("Could not open %s: %s", MODULE_FILE, strerror(errno));
153        property_set(DRIVER_PROP_NAME, "unloaded");
154        return 0;
155    }
156    while ((fgets(line, sizeof(line), proc)) != NULL) {
157        if (strncmp(line, DRIVER_MODULE_TAG, strlen(DRIVER_MODULE_TAG)) == 0) {
158            fclose(proc);
159            return 1;
160        }
161    }
162    fclose(proc);
163    property_set(DRIVER_PROP_NAME, "unloaded");
164    return 0;
165}
166
167int wifi_load_driver()
168{
169    char driver_status[PROPERTY_VALUE_MAX];
170    int count = 100; /* wait at most 20 seconds for completion */
171
172    if (check_driver_loaded()) {
173        return 0;
174    }
175
176    if (insmod(DRIVER_MODULE_PATH, DRIVER_MODULE_ARG) < 0)
177        return -1;
178
179    if (strcmp(FIRMWARE_LOADER,"") == 0) {
180        usleep(500000);
181        property_set(DRIVER_PROP_NAME, "ok");
182    }
183    else {
184        property_set("ctl.start", FIRMWARE_LOADER);
185    }
186    sched_yield();
187    while (count-- > 0) {
188        if (property_get(DRIVER_PROP_NAME, driver_status, NULL)) {
189            if (strcmp(driver_status, "ok") == 0)
190                return 0;
191            else if (strcmp(DRIVER_PROP_NAME, "failed") == 0)
192                return -1;
193        }
194        usleep(200000);
195    }
196    property_set(DRIVER_PROP_NAME, "timeout");
197    return -1;
198}
199
200int wifi_unload_driver()
201{
202    int count = 20; /* wait at most 10 seconds for completion */
203
204    if (rmmod(DRIVER_MODULE_NAME) == 0) {
205	while (count-- > 0) {
206	    if (!check_driver_loaded())
207		break;
208    	    usleep(500000);
209	}
210	if (count) {
211    	    return 0;
212	}
213	return -1;
214    } else
215        return -1;
216}
217
218int ensure_config_file_exists()
219{
220    char buf[2048];
221    int srcfd, destfd;
222    int nread;
223
224    if (access(SUPP_CONFIG_FILE, R_OK|W_OK) == 0) {
225        return 0;
226    } else if (errno != ENOENT) {
227        LOGE("Cannot access \"%s\": %s", SUPP_CONFIG_FILE, strerror(errno));
228        return -1;
229    }
230
231    srcfd = open(SUPP_CONFIG_TEMPLATE, O_RDONLY);
232    if (srcfd < 0) {
233        LOGE("Cannot open \"%s\": %s", SUPP_CONFIG_TEMPLATE, strerror(errno));
234        return -1;
235    }
236
237    destfd = open(SUPP_CONFIG_FILE, O_CREAT|O_WRONLY, 0660);
238    if (destfd < 0) {
239        close(srcfd);
240        LOGE("Cannot create \"%s\": %s", SUPP_CONFIG_FILE, strerror(errno));
241        return -1;
242    }
243
244    while ((nread = read(srcfd, buf, sizeof(buf))) != 0) {
245        if (nread < 0) {
246            LOGE("Error reading \"%s\": %s", SUPP_CONFIG_TEMPLATE, strerror(errno));
247            close(srcfd);
248            close(destfd);
249            unlink(SUPP_CONFIG_FILE);
250            return -1;
251        }
252        write(destfd, buf, nread);
253    }
254
255    close(destfd);
256    close(srcfd);
257
258    if (chown(SUPP_CONFIG_FILE, AID_SYSTEM, AID_WIFI) < 0) {
259        LOGE("Error changing group ownership of %s to %d: %s",
260             SUPP_CONFIG_FILE, AID_WIFI, strerror(errno));
261        unlink(SUPP_CONFIG_FILE);
262        return -1;
263    }
264    return 0;
265}
266
267int wifi_start_supplicant()
268{
269    char supp_status[PROPERTY_VALUE_MAX] = {'\0'};
270    int count = 200; /* wait at most 20 seconds for completion */
271#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
272    const prop_info *pi;
273    unsigned serial = 0;
274#endif
275
276    /* Check whether already running */
277    if (property_get(SUPP_PROP_NAME, supp_status, NULL)
278            && strcmp(supp_status, "running") == 0) {
279        return 0;
280    }
281
282    /* Before starting the daemon, make sure its config file exists */
283    if (ensure_config_file_exists() < 0) {
284        LOGE("Wi-Fi will not be enabled");
285        return -1;
286    }
287
288    /* Clear out any stale socket files that might be left over. */
289    wpa_ctrl_cleanup();
290
291#ifdef HAVE_LIBC_SYSTEM_PROPERTIES
292    /*
293     * Get a reference to the status property, so we can distinguish
294     * the case where it goes stopped => running => stopped (i.e.,
295     * it start up, but fails right away) from the case in which
296     * it starts in the stopped state and never manages to start
297     * running at all.
298     */
299    pi = __system_property_find(SUPP_PROP_NAME);
300    if (pi != NULL) {
301        serial = pi->serial;
302    }
303#endif
304    property_set("ctl.start", SUPPLICANT_NAME);
305    sched_yield();
306
307    while (count-- > 0) {
308 #ifdef HAVE_LIBC_SYSTEM_PROPERTIES
309        if (pi == NULL) {
310            pi = __system_property_find(SUPP_PROP_NAME);
311        }
312        if (pi != NULL) {
313            __system_property_read(pi, NULL, supp_status);
314            if (strcmp(supp_status, "running") == 0) {
315                return 0;
316            } else if (pi->serial != serial &&
317                    strcmp(supp_status, "stopped") == 0) {
318                return -1;
319            }
320        }
321#else
322        if (property_get(SUPP_PROP_NAME, supp_status, NULL)) {
323            if (strcmp(supp_status, "running") == 0)
324                return 0;
325        }
326#endif
327        usleep(100000);
328    }
329    return -1;
330}
331
332int wifi_stop_supplicant()
333{
334    char supp_status[PROPERTY_VALUE_MAX] = {'\0'};
335    int count = 50; /* wait at most 5 seconds for completion */
336
337    /* Check whether supplicant already stopped */
338    if (property_get(SUPP_PROP_NAME, supp_status, NULL)
339        && strcmp(supp_status, "stopped") == 0) {
340        return 0;
341    }
342
343    property_set("ctl.stop", SUPPLICANT_NAME);
344    sched_yield();
345
346    while (count-- > 0) {
347        if (property_get(SUPP_PROP_NAME, supp_status, NULL)) {
348            if (strcmp(supp_status, "stopped") == 0)
349                return 0;
350        }
351        usleep(100000);
352    }
353    return -1;
354}
355
356int wifi_connect_to_supplicant()
357{
358    char ifname[256];
359    char supp_status[PROPERTY_VALUE_MAX] = {'\0'};
360
361    /* Make sure supplicant is running */
362    if (!property_get(SUPP_PROP_NAME, supp_status, NULL)
363            || strcmp(supp_status, "running") != 0) {
364        LOGE("Supplicant not running, cannot connect");
365        return -1;
366    }
367
368    property_get("wifi.interface", iface, WIFI_TEST_INTERFACE);
369
370    if (access(IFACE_DIR, F_OK) == 0) {
371        snprintf(ifname, sizeof(ifname), "%s/%s", IFACE_DIR, iface);
372    } else {
373        strlcpy(ifname, iface, sizeof(ifname));
374    }
375
376    ctrl_conn = wpa_ctrl_open(ifname);
377    if (ctrl_conn == NULL) {
378        LOGE("Unable to open connection to supplicant on \"%s\": %s",
379             ifname, strerror(errno));
380        return -1;
381    }
382    monitor_conn = wpa_ctrl_open(ifname);
383    if (monitor_conn == NULL) {
384        wpa_ctrl_close(ctrl_conn);
385        ctrl_conn = NULL;
386        return -1;
387    }
388    if (wpa_ctrl_attach(monitor_conn) != 0) {
389        wpa_ctrl_close(monitor_conn);
390        wpa_ctrl_close(ctrl_conn);
391        ctrl_conn = monitor_conn = NULL;
392        return -1;
393    }
394    return 0;
395}
396
397int wifi_send_command(struct wpa_ctrl *ctrl, const char *cmd, char *reply, size_t *reply_len)
398{
399    int ret;
400
401    if (ctrl_conn == NULL) {
402        LOGV("Not connected to wpa_supplicant - \"%s\" command dropped.\n", cmd);
403        return -1;
404    }
405    ret = wpa_ctrl_request(ctrl, cmd, strlen(cmd), reply, reply_len, NULL);
406    if (ret == -2) {
407        LOGD("'%s' command timed out.\n", cmd);
408        return -2;
409    } else if (ret < 0 || strncmp(reply, "FAIL", 4) == 0) {
410        return -1;
411    }
412    if (strncmp(cmd, "PING", 4) == 0) {
413        reply[*reply_len] = '\0';
414    }
415    return 0;
416}
417
418int wifi_wait_for_event(char *buf, size_t buflen)
419{
420    size_t nread = buflen - 1;
421    int fd;
422    fd_set rfds;
423    int result;
424    struct timeval tval;
425    struct timeval *tptr;
426
427    if (monitor_conn == NULL)
428        return 0;
429
430    result = wpa_ctrl_recv(monitor_conn, buf, &nread);
431    if (result < 0) {
432        LOGD("wpa_ctrl_recv failed: %s\n", strerror(errno));
433        return -1;
434    }
435    buf[nread] = '\0';
436    /* LOGD("wait_for_event: result=%d nread=%d string=\"%s\"\n", result, nread, buf); */
437    /* Check for EOF on the socket */
438    if (result == 0 && nread == 0) {
439        /* Fabricate an event to pass up */
440        LOGD("Received EOF on supplicant socket\n");
441        strncpy(buf, WPA_EVENT_TERMINATING " - signal 0 received", buflen-1);
442        buf[buflen-1] = '\0';
443        return strlen(buf);
444    }
445    /*
446     * Events strings are in the format
447     *
448     *     <N>CTRL-EVENT-XXX
449     *
450     * where N is the message level in numerical form (0=VERBOSE, 1=DEBUG,
451     * etc.) and XXX is the event name. The level information is not useful
452     * to us, so strip it off.
453     */
454    if (buf[0] == '<') {
455        char *match = strchr(buf, '>');
456        if (match != NULL) {
457            nread -= (match+1-buf);
458            memmove(buf, match+1, nread+1);
459        }
460    }
461    return nread;
462}
463
464void wifi_close_supplicant_connection()
465{
466    if (ctrl_conn != NULL) {
467        wpa_ctrl_close(ctrl_conn);
468        ctrl_conn = NULL;
469    }
470    if (monitor_conn != NULL) {
471        wpa_ctrl_close(monitor_conn);
472        monitor_conn = NULL;
473    }
474}
475
476int wifi_command(const char *command, char *reply, size_t *reply_len)
477{
478    return wifi_send_command(ctrl_conn, command, reply, reply_len);
479}
480