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/types.h>
25#include <sys/wait.h>
26
27#include <dirent.h>
28
29#include <netinet/in.h>
30#include <arpa/inet.h>
31
32#define LOG_TAG "PppController"
33#include <cutils/log.h>
34
35#include "PppController.h"
36
37PppController::PppController() {
38    mTtys = new TtyCollection();
39    mPid = 0;
40}
41
42PppController::~PppController() {
43    TtyCollection::iterator it;
44
45    for (it = mTtys->begin(); it != mTtys->end(); ++it) {
46        free(*it);
47    }
48    mTtys->clear();
49}
50
51int PppController::attachPppd(const char *tty, struct in_addr local,
52                              struct in_addr remote, struct in_addr dns1,
53                              struct in_addr dns2) {
54    pid_t pid;
55
56    if (mPid) {
57        ALOGE("Multiple PPPD instances not currently supported");
58        errno = EBUSY;
59        return -1;
60    }
61
62    TtyCollection::iterator it;
63    for (it = mTtys->begin(); it != mTtys->end(); ++it) {
64        if (!strcmp(tty, *it)) {
65            break;
66        }
67    }
68    if (it == mTtys->end()) {
69        ALOGE("Invalid tty '%s' specified", tty);
70        errno = -EINVAL;
71        return -1;
72    }
73
74    if ((pid = fork()) < 0) {
75        ALOGE("fork failed (%s)", strerror(errno));
76        return -1;
77    }
78
79    if (!pid) {
80        char *l = strdup(inet_ntoa(local));
81        char *r = strdup(inet_ntoa(remote));
82        char *d1 = strdup(inet_ntoa(dns1));
83        char *d2 = strdup(inet_ntoa(dns2));
84        char dev[32];
85        char *lr;
86
87        asprintf(&lr, "%s:%s", l, r);
88        free(l);
89        free(r);
90
91        snprintf(dev, sizeof(dev), "/dev/%s", tty);
92
93        // TODO: Deal with pppd bailing out after 99999 seconds of being started
94        // but not getting a connection
95        if (execl("/system/bin/pppd", "/system/bin/pppd", "-detach", dev, "115200",
96                  lr, "ms-dns", d1, "ms-dns", d2, "lcp-max-configure", "99999", (char *) NULL)) {
97            ALOGE("execl failed (%s)", strerror(errno));
98        }
99        free(lr);
100        free(d1);
101        free(d2);
102        ALOGE("Should never get here!");
103        return 0;
104    } else {
105        mPid = pid;
106    }
107    return 0;
108}
109
110int PppController::detachPppd(const char *tty) {
111
112    if (mPid == 0) {
113        ALOGE("PPPD already stopped");
114        return 0;
115    }
116
117    ALOGD("Stopping PPPD services on port %s", tty);
118    kill(mPid, SIGTERM);
119    waitpid(mPid, NULL, 0);
120    mPid = 0;
121    ALOGD("PPPD services on port %s stopped", tty);
122    return 0;
123}
124
125TtyCollection *PppController::getTtyList() {
126    updateTtyList();
127    return mTtys;
128}
129
130int PppController::updateTtyList() {
131    TtyCollection::iterator it;
132
133    for (it = mTtys->begin(); it != mTtys->end(); ++it) {
134        free(*it);
135    }
136    mTtys->clear();
137
138    DIR *d = opendir("/sys/class/tty");
139    if (!d) {
140        ALOGE("Error opening /sys/class/tty (%s)", strerror(errno));
141        return -1;
142    }
143
144    struct dirent *de;
145    while ((de = readdir(d))) {
146        if (de->d_name[0] == '.')
147            continue;
148        if ((!strncmp(de->d_name, "tty", 3)) && (strlen(de->d_name) > 3)) {
149            mTtys->push_back(strdup(de->d_name));
150        }
151    }
152    closedir(d);
153    return 0;
154}
155