SoftapController.cpp revision 2f8e725e19e151acc1f8cf564f91a2ef09139f44 
1/*
2 * Copyright (C) 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 <errno.h>
19#include <fcntl.h>
20#include <string.h>
21
22#include <sys/socket.h>
23#include <sys/stat.h>
24#include <sys/ioctl.h>
25#include <sys/types.h>
26#include <sys/wait.h>
27
28#include <netinet/in.h>
29#include <arpa/inet.h>
30
31#include <linux/wireless.h>
32
33#include <openssl/evp.h>
34#include <openssl/sha.h>
35
36#define LOG_TAG "SoftapController"
37#include <cutils/log.h>
38#include <netutils/ifc.h>
39#include <private/android_filesystem_config.h>
40#include "wifi.h"
41#include "ResponseCode.h"
42
43#include "SoftapController.h"
44
45static const char HOSTAPD_CONF_FILE[]    = "/data/misc/wifi/hostapd.conf";
46static const char HOSTAPD_BIN_FILE[]    = "/system/bin/hostapd";
47
48SoftapController::SoftapController()
49    : mPid(0) {}
50
51SoftapController::~SoftapController() {
52}
53
54int SoftapController::startSoftap() {
55    pid_t pid = 1;
56
57    if (mPid) {
58        ALOGE("SoftAP is already running");
59        return ResponseCode::SoftapStatusResult;
60    }
61
62    if (ensure_entropy_file_exists() < 0) {
63        ALOGE("Wi-Fi entropy file was not created");
64    }
65
66    if ((pid = fork()) < 0) {
67        ALOGE("fork failed (%s)", strerror(errno));
68        return ResponseCode::ServiceStartFailed;
69    }
70
71    if (!pid) {
72        ensure_entropy_file_exists();
73        if (execl(HOSTAPD_BIN_FILE, HOSTAPD_BIN_FILE,
74                  "-e", WIFI_ENTROPY_FILE,
75                  HOSTAPD_CONF_FILE, (char *) NULL)) {
76            ALOGE("execl failed (%s)", strerror(errno));
77        }
78        ALOGE("SoftAP failed to start");
79        return ResponseCode::ServiceStartFailed;
80    } else {
81        mPid = pid;
82        ALOGD("SoftAP started successfully");
83        usleep(AP_BSS_START_DELAY);
84    }
85    return ResponseCode::SoftapStatusResult;
86}
87
88int SoftapController::stopSoftap() {
89
90    if (mPid == 0) {
91        ALOGE("SoftAP is not running");
92        return ResponseCode::SoftapStatusResult;
93    }
94
95    ALOGD("Stopping the SoftAP service...");
96    kill(mPid, SIGTERM);
97    waitpid(mPid, NULL, 0);
98
99    mPid = 0;
100    ALOGD("SoftAP stopped successfully");
101    usleep(AP_BSS_STOP_DELAY);
102    return ResponseCode::SoftapStatusResult;
103}
104
105bool SoftapController::isSoftapStarted() {
106    return (mPid != 0);
107}
108
109/*
110 * Arguments:
111 *  argv[2] - wlan interface
112 *  argv[3] - SSID
113 *  argv[4] - Broadcast/Hidden
114 *  argv[5] - Channel
115 *  argv[6] - Security
116 *  argv[7] - Key
117 */
118int SoftapController::setSoftap(int argc, char *argv[]) {
119    char psk_str[2*SHA256_DIGEST_LENGTH+1];
120    int ret = ResponseCode::SoftapStatusResult;
121    int fd;
122    int hidden = 0;
123    int channel = AP_CHANNEL_DEFAULT;
124    char *wbuf = NULL;
125    char *fbuf = NULL;
126
127    if (argc < 5) {
128        ALOGE("Softap set is missing arguments. Please use:");
129        ALOGE("softap <wlan iface> <SSID> <hidden/broadcast> <channel> <wpa2?-psk|open> <passphrase>");
130        return ResponseCode::CommandSyntaxError;
131    }
132
133    if (!strcasecmp(argv[4], "hidden"))
134        hidden = 1;
135
136    if (argc >= 5) {
137        channel = atoi(argv[5]);
138        if (channel <= 0)
139            channel = AP_CHANNEL_DEFAULT;
140    }
141
142    asprintf(&wbuf, "interface=%s\ndriver=nl80211\nctrl_interface="
143            "/data/misc/wifi/hostapd\nssid=%s\nchannel=%d\nieee80211n=1\n"
144            "hw_mode=%c\nignore_broadcast_ssid=%d\nwowlan_triggers=any\n",
145            argv[2], argv[3], channel, (channel <= 14) ? 'g' : 'a', hidden);
146
147    if (argc > 7) {
148        if (!strcmp(argv[6], "wpa-psk")) {
149            generatePsk(argv[3], argv[7], psk_str);
150            asprintf(&fbuf, "%swpa=3\nwpa_pairwise=TKIP CCMP\nwpa_psk=%s\n", wbuf, psk_str);
151        } else if (!strcmp(argv[6], "wpa2-psk")) {
152            generatePsk(argv[3], argv[7], psk_str);
153            asprintf(&fbuf, "%swpa=2\nrsn_pairwise=CCMP\nwpa_psk=%s\n", wbuf, psk_str);
154        } else if (!strcmp(argv[6], "open")) {
155            asprintf(&fbuf, "%s", wbuf);
156        }
157    } else if (argc > 6) {
158        if (!strcmp(argv[6], "open")) {
159            asprintf(&fbuf, "%s", wbuf);
160        }
161    } else {
162        asprintf(&fbuf, "%s", wbuf);
163    }
164
165    fd = open(HOSTAPD_CONF_FILE, O_CREAT | O_TRUNC | O_WRONLY | O_NOFOLLOW, 0660);
166    if (fd < 0) {
167        ALOGE("Cannot update \"%s\": %s", HOSTAPD_CONF_FILE, strerror(errno));
168        free(wbuf);
169        free(fbuf);
170        return ResponseCode::OperationFailed;
171    }
172    if (write(fd, fbuf, strlen(fbuf)) < 0) {
173        ALOGE("Cannot write to \"%s\": %s", HOSTAPD_CONF_FILE, strerror(errno));
174        ret = ResponseCode::OperationFailed;
175    }
176    free(wbuf);
177    free(fbuf);
178
179    /* Note: apparently open can fail to set permissions correctly at times */
180    if (fchmod(fd, 0660) < 0) {
181        ALOGE("Error changing permissions of %s to 0660: %s",
182                HOSTAPD_CONF_FILE, strerror(errno));
183        close(fd);
184        unlink(HOSTAPD_CONF_FILE);
185        return ResponseCode::OperationFailed;
186    }
187
188    if (fchown(fd, AID_SYSTEM, AID_WIFI) < 0) {
189        ALOGE("Error changing group ownership of %s to %d: %s",
190                HOSTAPD_CONF_FILE, AID_WIFI, strerror(errno));
191        close(fd);
192        unlink(HOSTAPD_CONF_FILE);
193        return ResponseCode::OperationFailed;
194    }
195
196    close(fd);
197    return ret;
198}
199
200/*
201 * Arguments:
202 *	argv[2] - interface name
203 *	argv[3] - AP or P2P or STA
204 */
205int SoftapController::fwReloadSoftap(int argc, char *argv[])
206{
207    char *fwpath = NULL;
208
209    if (argc < 4) {
210        ALOGE("SoftAP fwreload is missing arguments. Please use: softap <wlan iface> <AP|P2P|STA>");
211        return ResponseCode::CommandSyntaxError;
212    }
213
214    if (strcmp(argv[3], "AP") == 0) {
215        fwpath = (char *)wifi_get_fw_path(WIFI_GET_FW_PATH_AP);
216    } else if (strcmp(argv[3], "P2P") == 0) {
217        fwpath = (char *)wifi_get_fw_path(WIFI_GET_FW_PATH_P2P);
218    } else if (strcmp(argv[3], "STA") == 0) {
219        fwpath = (char *)wifi_get_fw_path(WIFI_GET_FW_PATH_STA);
220    }
221    if (!fwpath)
222        return ResponseCode::CommandParameterError;
223    if (wifi_change_fw_path((const char *)fwpath)) {
224        ALOGE("Softap fwReload failed");
225        return ResponseCode::OperationFailed;
226    }
227    else {
228        ALOGD("Softap fwReload - Ok");
229    }
230    return ResponseCode::SoftapStatusResult;
231}
232
233void SoftapController::generatePsk(char *ssid, char *passphrase, char *psk_str) {
234    unsigned char psk[SHA256_DIGEST_LENGTH];
235    int j;
236    // Use the PKCS#5 PBKDF2 with 4096 iterations
237    PKCS5_PBKDF2_HMAC_SHA1(passphrase, strlen(passphrase),
238            reinterpret_cast<const unsigned char *>(ssid), strlen(ssid),
239            4096, SHA256_DIGEST_LENGTH, psk);
240    for (j=0; j < SHA256_DIGEST_LENGTH; j++) {
241        sprintf(&psk_str[j*2], "%02x", psk[j]);
242    }
243}
244