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 #include <errno.h>
17 #include <string.h>
18 #include <stdlib.h>
19
20 #define LOG_TAG "FrameworkListener"
21
22 #include <cutils/log.h>
23
24 #include <sysutils/FrameworkListener.h>
25 #include <sysutils/FrameworkCommand.h>
26 #include <sysutils/SocketClient.h>
27
28 static const int CMD_BUF_SIZE = 1024;
29
30 #define UNUSED __attribute__((unused))
31
FrameworkListener(const char * socketName,bool withSeq)32 FrameworkListener::FrameworkListener(const char *socketName, bool withSeq) :
33 SocketListener(socketName, true, withSeq) {
34 init(socketName, withSeq);
35 }
36
FrameworkListener(const char * socketName)37 FrameworkListener::FrameworkListener(const char *socketName) :
38 SocketListener(socketName, true, false) {
39 init(socketName, false);
40 }
41
FrameworkListener(int sock)42 FrameworkListener::FrameworkListener(int sock) :
43 SocketListener(sock, true) {
44 init(NULL, false);
45 }
46
init(const char * socketName UNUSED,bool withSeq)47 void FrameworkListener::init(const char *socketName UNUSED, bool withSeq) {
48 mCommands = new FrameworkCommandCollection();
49 errorRate = 0;
50 mCommandCount = 0;
51 mWithSeq = withSeq;
52 mSkipToNextNullByte = false;
53 }
54
onDataAvailable(SocketClient * c)55 bool FrameworkListener::onDataAvailable(SocketClient *c) {
56 char buffer[CMD_BUF_SIZE];
57 int len;
58
59 len = TEMP_FAILURE_RETRY(read(c->getSocket(), buffer, sizeof(buffer)));
60 if (len < 0) {
61 SLOGE("read() failed (%s)", strerror(errno));
62 return false;
63 } else if (!len) {
64 return false;
65 } else if (buffer[len-1] != '\0') {
66 SLOGW("String is not zero-terminated");
67 android_errorWriteLog(0x534e4554, "29831647");
68 c->sendMsg(500, "Command too large for buffer", false);
69 mSkipToNextNullByte = true;
70 return false;
71 }
72
73 int offset = 0;
74 int i;
75
76 for (i = 0; i < len; i++) {
77 if (buffer[i] == '\0') {
78 /* IMPORTANT: dispatchCommand() expects a zero-terminated string */
79 if (mSkipToNextNullByte) {
80 mSkipToNextNullByte = false;
81 } else {
82 dispatchCommand(c, buffer + offset);
83 }
84 offset = i + 1;
85 }
86 }
87
88 mSkipToNextNullByte = false;
89 return true;
90 }
91
registerCmd(FrameworkCommand * cmd)92 void FrameworkListener::registerCmd(FrameworkCommand *cmd) {
93 mCommands->push_back(cmd);
94 }
95
dispatchCommand(SocketClient * cli,char * data)96 void FrameworkListener::dispatchCommand(SocketClient *cli, char *data) {
97 FrameworkCommandCollection::iterator i;
98 int argc = 0;
99 char *argv[FrameworkListener::CMD_ARGS_MAX];
100 char tmp[CMD_BUF_SIZE];
101 char *p = data;
102 char *q = tmp;
103 char *qlimit = tmp + sizeof(tmp) - 1;
104 bool esc = false;
105 bool quote = false;
106 bool haveCmdNum = !mWithSeq;
107
108 memset(argv, 0, sizeof(argv));
109 memset(tmp, 0, sizeof(tmp));
110 while(*p) {
111 if (*p == '\\') {
112 if (esc) {
113 if (q >= qlimit)
114 goto overflow;
115 *q++ = '\\';
116 esc = false;
117 } else
118 esc = true;
119 p++;
120 continue;
121 } else if (esc) {
122 if (*p == '"') {
123 if (q >= qlimit)
124 goto overflow;
125 *q++ = '"';
126 } else if (*p == '\\') {
127 if (q >= qlimit)
128 goto overflow;
129 *q++ = '\\';
130 } else {
131 cli->sendMsg(500, "Unsupported escape sequence", false);
132 goto out;
133 }
134 p++;
135 esc = false;
136 continue;
137 }
138
139 if (*p == '"') {
140 if (quote)
141 quote = false;
142 else
143 quote = true;
144 p++;
145 continue;
146 }
147
148 if (q >= qlimit)
149 goto overflow;
150 *q = *p++;
151 if (!quote && *q == ' ') {
152 *q = '\0';
153 if (!haveCmdNum) {
154 char *endptr;
155 int cmdNum = (int)strtol(tmp, &endptr, 0);
156 if (endptr == NULL || *endptr != '\0') {
157 cli->sendMsg(500, "Invalid sequence number", false);
158 goto out;
159 }
160 cli->setCmdNum(cmdNum);
161 haveCmdNum = true;
162 } else {
163 if (argc >= CMD_ARGS_MAX)
164 goto overflow;
165 argv[argc++] = strdup(tmp);
166 }
167 memset(tmp, 0, sizeof(tmp));
168 q = tmp;
169 continue;
170 }
171 q++;
172 }
173
174 *q = '\0';
175 if (argc >= CMD_ARGS_MAX)
176 goto overflow;
177 argv[argc++] = strdup(tmp);
178 #if 0
179 for (int k = 0; k < argc; k++) {
180 SLOGD("arg[%d] = '%s'", k, argv[k]);
181 }
182 #endif
183
184 if (quote) {
185 cli->sendMsg(500, "Unclosed quotes error", false);
186 goto out;
187 }
188
189 if (errorRate && (++mCommandCount % errorRate == 0)) {
190 /* ignore this command - let the timeout handler handle it */
191 SLOGE("Faking a timeout");
192 goto out;
193 }
194
195 for (i = mCommands->begin(); i != mCommands->end(); ++i) {
196 FrameworkCommand *c = *i;
197
198 if (!strcmp(argv[0], c->getCommand())) {
199 if (c->runCommand(cli, argc, argv)) {
200 SLOGW("Handler '%s' error (%s)", c->getCommand(), strerror(errno));
201 }
202 goto out;
203 }
204 }
205 cli->sendMsg(500, "Command not recognized", false);
206 out:
207 int j;
208 for (j = 0; j < argc; j++)
209 free(argv[j]);
210 return;
211
212 overflow:
213 LOG_EVENT_INT(78001, cli->getUid());
214 cli->sendMsg(500, "Command too long", false);
215 goto out;
216 }
217