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 <log/log.h>
34
35 #include "PppController.h"
36
PppController()37 PppController::PppController() {
38 mTtys = new TtyCollection();
39 mPid = 0;
40 }
41
~PppController()42 PppController::~PppController() {
43 TtyCollection::iterator it;
44
45 for (it = mTtys->begin(); it != mTtys->end(); ++it) {
46 free(*it);
47 }
48 mTtys->clear();
49 }
50
attachPppd(const char * tty,struct in_addr local,struct in_addr remote,struct in_addr dns1,struct in_addr dns2)51 int 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 *) nullptr)) {
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
detachPppd(const char * tty)110 int 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, nullptr, 0);
120 mPid = 0;
121 ALOGD("PPPD services on port %s stopped", tty);
122 return 0;
123 }
124
getTtyList()125 TtyCollection *PppController::getTtyList() {
126 updateTtyList();
127 return mTtys;
128 }
129
updateTtyList()130 int 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