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 ((pid = fork()) < 0) {
63        ALOGE("fork failed (%s)", strerror(errno));
64        return ResponseCode::ServiceStartFailed;
65    }
66
67    if (!pid) {
68        ensure_entropy_file_exists();
69        if (execl(HOSTAPD_BIN_FILE, HOSTAPD_BIN_FILE,
70                  "-e", WIFI_ENTROPY_FILE,
71                  HOSTAPD_CONF_FILE, (char *) NULL)) {
72            ALOGE("execl failed (%s)", strerror(errno));
73        }
74        ALOGE("SoftAP failed to start");
75        return ResponseCode::ServiceStartFailed;
76    } else {
77        mPid = pid;
78        ALOGD("SoftAP started successfully");
79        usleep(AP_BSS_START_DELAY);
80    }
81    return ResponseCode::SoftapStatusResult;
82}
83
84int SoftapController::stopSoftap() {
85
86    if (mPid == 0) {
87        ALOGE("SoftAP is not running");
88        return ResponseCode::SoftapStatusResult;
89    }
90
91    ALOGD("Stopping the SoftAP service...");
92    kill(mPid, SIGTERM);
93    waitpid(mPid, NULL, 0);
94
95    mPid = 0;
96    ALOGD("SoftAP stopped successfully");
97    usleep(AP_BSS_STOP_DELAY);
98    return ResponseCode::SoftapStatusResult;
99}
100
101bool SoftapController::isSoftapStarted() {
102    return (mPid != 0);
103}
104
105/*
106 * Arguments:
107 *  argv[2] - wlan interface
108 *  argv[3] - SSID
109 *  argv[4] - Broadcast/Hidden
110 *  argv[5] - Channel
111 *  argv[6] - Security
112 *  argv[7] - Key
113 */
114int SoftapController::setSoftap(int argc, char *argv[]) {
115    char psk_str[2*SHA256_DIGEST_LENGTH+1];
116    int ret = ResponseCode::SoftapStatusResult;
117    int i = 0;
118    int fd;
119    int hidden = 0;
120    int channel = AP_CHANNEL_DEFAULT;
121    char *wbuf = NULL;
122    char *fbuf = NULL;
123
124    if (argc < 5) {
125        ALOGE("Softap set is missing arguments. Please use:");
126        ALOGE("softap <wlan iface> <SSID> <hidden/broadcast> <channel> <wpa2?-psk|open> <passphrase>");
127        return ResponseCode::CommandSyntaxError;
128    }
129
130    if (!strcasecmp(argv[4], "hidden"))
131        hidden = 1;
132
133    if (argc >= 5) {
134        channel = atoi(argv[5]);
135        if (channel <= 0)
136            channel = AP_CHANNEL_DEFAULT;
137    }
138
139    asprintf(&wbuf, "interface=%s\ndriver=nl80211\nctrl_interface="
140            "/data/misc/wifi/hostapd\nssid=%s\nchannel=%d\nieee80211n=1\n"
141            "hw_mode=g\nignore_broadcast_ssid=%d\n",
142            argv[2], argv[3], channel, hidden);
143
144    if (argc > 7) {
145        if (!strcmp(argv[6], "wpa-psk")) {
146            generatePsk(argv[3], argv[7], psk_str);
147            asprintf(&fbuf, "%swpa=1\nwpa_pairwise=TKIP CCMP\nwpa_psk=%s\n", wbuf, psk_str);
148        } else if (!strcmp(argv[6], "wpa2-psk")) {
149            generatePsk(argv[3], argv[7], psk_str);
150            asprintf(&fbuf, "%swpa=2\nrsn_pairwise=CCMP\nwpa_psk=%s\n", wbuf, psk_str);
151        } else if (!strcmp(argv[6], "open")) {
152            asprintf(&fbuf, "%s", wbuf);
153        }
154    } else if (argc > 6) {
155        if (!strcmp(argv[6], "open")) {
156            asprintf(&fbuf, "%s", wbuf);
157        }
158    } else {
159        asprintf(&fbuf, "%s", wbuf);
160    }
161
162    fd = open(HOSTAPD_CONF_FILE, O_CREAT | O_TRUNC | O_WRONLY | O_NOFOLLOW, 0660);
163    if (fd < 0) {
164        ALOGE("Cannot update \"%s\": %s", HOSTAPD_CONF_FILE, strerror(errno));
165        free(wbuf);
166        free(fbuf);
167        return ResponseCode::OperationFailed;
168    }
169    if (write(fd, fbuf, strlen(fbuf)) < 0) {
170        ALOGE("Cannot write to \"%s\": %s", HOSTAPD_CONF_FILE, strerror(errno));
171        ret = ResponseCode::OperationFailed;
172    }
173    free(wbuf);
174    free(fbuf);
175
176    /* Note: apparently open can fail to set permissions correctly at times */
177    if (fchmod(fd, 0660) < 0) {
178        ALOGE("Error changing permissions of %s to 0660: %s",
179                HOSTAPD_CONF_FILE, strerror(errno));
180        close(fd);
181        unlink(HOSTAPD_CONF_FILE);
182        return ResponseCode::OperationFailed;
183    }
184
185    if (fchown(fd, AID_SYSTEM, AID_WIFI) < 0) {
186        ALOGE("Error changing group ownership of %s to %d: %s",
187                HOSTAPD_CONF_FILE, AID_WIFI, strerror(errno));
188        close(fd);
189        unlink(HOSTAPD_CONF_FILE);
190        return ResponseCode::OperationFailed;
191    }
192
193    close(fd);
194    return ret;
195}
196
197/*
198 * Arguments:
199 *	argv[2] - interface name
200 *	argv[3] - AP or P2P or STA
201 */
202int SoftapController::fwReloadSoftap(int argc, char *argv[])
203{
204    int i = 0;
205    char *fwpath = NULL;
206
207    if (argc < 4) {
208        ALOGE("SoftAP fwreload is missing arguments. Please use: softap <wlan iface> <AP|P2P|STA>");
209        return ResponseCode::CommandSyntaxError;
210    }
211
212    if (strcmp(argv[3], "AP") == 0) {
213        fwpath = (char *)wifi_get_fw_path(WIFI_GET_FW_PATH_AP);
214    } else if (strcmp(argv[3], "P2P") == 0) {
215        fwpath = (char *)wifi_get_fw_path(WIFI_GET_FW_PATH_P2P);
216    } else if (strcmp(argv[3], "STA") == 0) {
217        fwpath = (char *)wifi_get_fw_path(WIFI_GET_FW_PATH_STA);
218    }
219    if (!fwpath)
220        return ResponseCode::CommandParameterError;
221    if (wifi_change_fw_path((const char *)fwpath)) {
222        ALOGE("Softap fwReload failed");
223        return ResponseCode::OperationFailed;
224    }
225    else {
226        ALOGD("Softap fwReload - Ok");
227    }
228    return ResponseCode::SoftapStatusResult;
229}
230
231void SoftapController::generatePsk(char *ssid, char *passphrase, char *psk_str) {
232    unsigned char psk[SHA256_DIGEST_LENGTH];
233    int j;
234    // Use the PKCS#5 PBKDF2 with 4096 iterations
235    PKCS5_PBKDF2_HMAC_SHA1(passphrase, strlen(passphrase),
236            reinterpret_cast<const unsigned char *>(ssid), strlen(ssid),
237            4096, SHA256_DIGEST_LENGTH, psk);
238    for (j=0; j < SHA256_DIGEST_LENGTH; j++) {
239        sprintf(&psk_str[j*2], "%02x", psk[j]);
240    }
241}
242