PppController.cpp revision ff2c0d8c13457e43f0d4bf06d3177271aac104c1 
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
37extern "C" int logwrap(int argc, const char **argv, int background);
38
39PppController::PppController() {
40    mTtys = new TtyCollection();
41    mPid = 0;
42}
43
44PppController::~PppController() {
45    TtyCollection::iterator it;
46
47    for (it = mTtys->begin(); it != mTtys->end(); ++it) {
48        free(*it);
49    }
50    mTtys->clear();
51}
52
53int PppController::attachPppd(const char *tty, struct in_addr local,
54                              struct in_addr remote, struct in_addr dns1,
55                              struct in_addr dns2) {
56    pid_t pid;
57
58    if (mPid) {
59        LOGE("Multiple PPPD instances not currently supported");
60        errno = EBUSY;
61        return -1;
62    }
63
64    TtyCollection::iterator it;
65    for (it = mTtys->begin(); it != mTtys->end(); ++it) {
66        if (!strcmp(tty, *it)) {
67            break;
68        }
69    }
70    if (it == mTtys->end()) {
71        LOGE("Invalid tty '%s' specified", tty);
72        errno = -EINVAL;
73        return -1;
74    }
75
76    if ((pid = fork()) < 0) {
77        LOGE("fork failed (%s)", strerror(errno));
78        return -1;
79    }
80
81    if (!pid) {
82        char *l = strdup(inet_ntoa(local));
83        char *r = strdup(inet_ntoa(remote));
84        char *d1 = strdup(inet_ntoa(dns1));
85        char *d2 = strdup(inet_ntoa(dns2));
86        char dev[32];
87        char *lr;
88
89        asprintf(&lr, "%s:%s", l, 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            LOGE("execl failed (%s)", strerror(errno));
98        }
99        LOGE("Should never get here!");
100        return 0;
101    } else {
102        mPid = pid;
103    }
104    return 0;
105}
106
107int PppController::detachPppd(const char *tty) {
108
109    if (mPid == 0) {
110        LOGE("PPPD already stopped");
111        return 0;
112    }
113
114    LOGD("Stopping PPPD services on port %s", tty);
115    kill(mPid, SIGTERM);
116    waitpid(mPid, NULL, 0);
117    mPid = 0;
118    LOGD("PPPD services on port %s stopped", tty);
119    return 0;
120}
121
122TtyCollection *PppController::getTtyList() {
123    updateTtyList();
124    return mTtys;
125}
126
127int PppController::updateTtyList() {
128    TtyCollection::iterator it;
129
130    for (it = mTtys->begin(); it != mTtys->end(); ++it) {
131        free(*it);
132    }
133    mTtys->clear();
134
135    DIR *d = opendir("/sys/class/tty");
136    if (!d) {
137        LOGE("Error opening /sys/class/tty (%s)", strerror(errno));
138        return -1;
139    }
140
141    struct dirent *de;
142    while ((de = readdir(d))) {
143        if (de->d_name[0] == '.')
144            continue;
145        if ((!strncmp(de->d_name, "tty", 3)) && (strlen(de->d_name) > 3)) {
146            mTtys->push_back(strdup(de->d_name));
147        }
148    }
149    closedir(d);
150    return 0;
151}
152