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 <errno.h>
18 #include <fcntl.h>
19 #include <stdlib.h>
20 #include <string.h>
21 #include <unistd.h>
22
23 #include <sys/socket.h>
24 #include <sys/stat.h>
25 #include <sys/types.h>
26 #include <sys/wait.h>
27
28 #include <dirent.h>
29
30 #include <netinet/in.h>
31 #include <arpa/inet.h>
32
33 #define LOG_TAG "PppController"
34 #include <log/log.h>
35
36 #include "PppController.h"
37
PppController()38 PppController::PppController() {
39 mTtys = new TtyCollection();
40 mPid = 0;
41 }
42
~PppController()43 PppController::~PppController() {
44 TtyCollection::iterator it;
45
46 for (it = mTtys->begin(); it != mTtys->end(); ++it) {
47 free(*it);
48 }
49 mTtys->clear();
50 }
51
attachPppd(const char * tty,struct in_addr local,struct in_addr remote,struct in_addr dns1,struct in_addr dns2)52 int PppController::attachPppd(const char *tty, struct in_addr local,
53 struct in_addr remote, struct in_addr dns1,
54 struct in_addr dns2) {
55 pid_t pid;
56
57 if (mPid) {
58 ALOGE("Multiple PPPD instances not currently supported");
59 errno = EBUSY;
60 return -1;
61 }
62
63 TtyCollection::iterator it;
64 for (it = mTtys->begin(); it != mTtys->end(); ++it) {
65 if (!strcmp(tty, *it)) {
66 break;
67 }
68 }
69 if (it == mTtys->end()) {
70 ALOGE("Invalid tty '%s' specified", tty);
71 errno = -EINVAL;
72 return -1;
73 }
74
75 if ((pid = fork()) < 0) {
76 ALOGE("fork failed (%s)", strerror(errno));
77 return -1;
78 }
79
80 if (!pid) {
81 char *l = strdup(inet_ntoa(local));
82 char *r = strdup(inet_ntoa(remote));
83 char *d1 = strdup(inet_ntoa(dns1));
84 char *d2 = strdup(inet_ntoa(dns2));
85 char dev[32];
86 char *lr;
87
88 asprintf(&lr, "%s:%s", l, r);
89 free(l);
90 free(r);
91
92 snprintf(dev, sizeof(dev), "/dev/%s", tty);
93
94 // TODO: Deal with pppd bailing out after 99999 seconds of being started
95 // but not getting a connection
96 if (execl("/system/bin/pppd", "/system/bin/pppd", "-detach", dev, "115200",
97 lr, "ms-dns", d1, "ms-dns", d2, "lcp-max-configure", "99999", (char *) nullptr)) {
98 ALOGE("execl failed (%s)", strerror(errno));
99 }
100 free(lr);
101 free(d1);
102 free(d2);
103 ALOGE("Should never get here!");
104 return 0;
105 } else {
106 mPid = pid;
107 }
108 return 0;
109 }
110
detachPppd(const char * tty)111 int PppController::detachPppd(const char *tty) {
112
113 if (mPid == 0) {
114 ALOGE("PPPD already stopped");
115 return 0;
116 }
117
118 ALOGD("Stopping PPPD services on port %s", tty);
119 kill(mPid, SIGTERM);
120 waitpid(mPid, nullptr, 0);
121 mPid = 0;
122 ALOGD("PPPD services on port %s stopped", tty);
123 return 0;
124 }
125
getTtyList()126 TtyCollection *PppController::getTtyList() {
127 updateTtyList();
128 return mTtys;
129 }
130
updateTtyList()131 int PppController::updateTtyList() {
132 TtyCollection::iterator it;
133
134 for (it = mTtys->begin(); it != mTtys->end(); ++it) {
135 free(*it);
136 }
137 mTtys->clear();
138
139 DIR *d = opendir("/sys/class/tty");
140 if (!d) {
141 ALOGE("Error opening /sys/class/tty (%s)", strerror(errno));
142 return -1;
143 }
144
145 struct dirent *de;
146 while ((de = readdir(d))) {
147 if (de->d_name[0] == '.')
148 continue;
149 if ((!strncmp(de->d_name, "tty", 3)) && (strlen(de->d_name) > 3)) {
150 mTtys->push_back(strdup(de->d_name));
151 }
152 }
153 closedir(d);
154 return 0;
155 }
156