Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2009 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 | #define LOG_TAG "BackupHelperDispatcher_native" |
| 18 | #include <utils/Log.h> |
| 19 | |
| 20 | #include "JNIHelp.h" |
| 21 | #include <android_runtime/AndroidRuntime.h> |
| 22 | |
| 23 | #include <sys/types.h> |
| 24 | #include <sys/uio.h> |
| 25 | #include <unistd.h> |
| 26 | |
| 27 | |
| 28 | #define VERSION_1_HEADER 0x01706c48 // 'Hlp'1 little endian |
| 29 | |
| 30 | namespace android |
| 31 | { |
| 32 | |
| 33 | struct chunk_header_v1 { |
| 34 | int headerSize; |
| 35 | int version; |
| 36 | int dataSize; // corresponds to Header.chunkSize |
| 37 | int nameLength; // not including the NULL terminator, which is not written to the file |
| 38 | }; |
| 39 | |
| 40 | // java.io.FileDescriptor |
| 41 | static jfieldID s_descriptorField = 0; |
| 42 | static jfieldID s_chunkSizeField = 0; |
| 43 | static jfieldID s_keyPrefixField = 0; |
| 44 | |
| 45 | static int |
| 46 | readHeader_native(JNIEnv* env, jobject clazz, jobject headerObj, jobject fdObj) |
| 47 | { |
| 48 | chunk_header_v1 flattenedHeader; |
| 49 | int fd; |
| 50 | ssize_t amt; |
| 51 | String8 keyPrefix; |
| 52 | char* buf; |
| 53 | |
| 54 | fd = env->GetIntField(fdObj, s_descriptorField); |
| 55 | |
| 56 | amt = read(fd, &flattenedHeader.headerSize, sizeof(flattenedHeader.headerSize)); |
| 57 | if (amt != sizeof(flattenedHeader.headerSize)) { |
| 58 | return -1; |
| 59 | } |
| 60 | |
| 61 | int remainingHeader = flattenedHeader.headerSize - sizeof(flattenedHeader.headerSize); |
| 62 | |
| 63 | if (flattenedHeader.headerSize < (int)sizeof(chunk_header_v1)) { |
| 64 | LOGW("Skipping unknown header: %d bytes", flattenedHeader.headerSize); |
| 65 | if (remainingHeader > 0) { |
| 66 | lseek(fd, remainingHeader, SEEK_CUR); |
| 67 | // >0 means skip this chunk |
| 68 | return 1; |
| 69 | } |
| 70 | } |
| 71 | |
| 72 | amt = read(fd, &flattenedHeader.version, |
| 73 | sizeof(chunk_header_v1)-sizeof(flattenedHeader.headerSize)); |
| 74 | if (amt <= 0) { |
| 75 | LOGW("Failed reading chunk header"); |
| 76 | return -1; |
| 77 | } |
| 78 | remainingHeader -= sizeof(chunk_header_v1)-sizeof(flattenedHeader.headerSize); |
| 79 | |
| 80 | if (flattenedHeader.version != VERSION_1_HEADER) { |
| 81 | LOGW("Skipping unknown header version: 0x%08x, %d bytes", flattenedHeader.version, |
| 82 | flattenedHeader.headerSize); |
| 83 | if (remainingHeader > 0) { |
| 84 | lseek(fd, remainingHeader, SEEK_CUR); |
| 85 | // >0 means skip this chunk |
| 86 | return 1; |
| 87 | } |
| 88 | } |
| 89 | |
Joe Onorato | 12a4da3 | 2009-06-26 17:18:01 -0400 | [diff] [blame] | 90 | #if 0 |
| 91 | LOGD("chunk header:"); |
| 92 | LOGD(" headerSize=%d", flattenedHeader.headerSize); |
| 93 | LOGD(" version=0x%08x", flattenedHeader.version); |
| 94 | LOGD(" dataSize=%d", flattenedHeader.dataSize); |
| 95 | LOGD(" nameLength=%d", flattenedHeader.nameLength); |
| 96 | #endif |
| 97 | |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 98 | if (flattenedHeader.dataSize < 0 || flattenedHeader.nameLength < 0 || |
| 99 | remainingHeader < flattenedHeader.nameLength) { |
| 100 | LOGW("Malformed V1 header remainingHeader=%d dataSize=%d nameLength=%d", remainingHeader, |
| 101 | flattenedHeader.dataSize, flattenedHeader.nameLength); |
| 102 | return -1; |
| 103 | } |
| 104 | |
| 105 | buf = keyPrefix.lockBuffer(flattenedHeader.nameLength); |
| 106 | if (buf == NULL) { |
| 107 | LOGW("unable to allocate %d bytes", flattenedHeader.nameLength); |
| 108 | return -1; |
| 109 | } |
| 110 | |
| 111 | amt = read(fd, buf, flattenedHeader.nameLength); |
Joe Onorato | 12a4da3 | 2009-06-26 17:18:01 -0400 | [diff] [blame] | 112 | buf[flattenedHeader.nameLength] = 0; |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 113 | |
| 114 | keyPrefix.unlockBuffer(flattenedHeader.nameLength); |
| 115 | |
| 116 | remainingHeader -= flattenedHeader.nameLength; |
| 117 | |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 118 | if (remainingHeader > 0) { |
| 119 | lseek(fd, remainingHeader, SEEK_CUR); |
| 120 | } |
| 121 | |
| 122 | env->SetIntField(headerObj, s_chunkSizeField, flattenedHeader.dataSize); |
| 123 | env->SetObjectField(headerObj, s_keyPrefixField, env->NewStringUTF(keyPrefix.string())); |
| 124 | |
| 125 | return 0; |
| 126 | } |
| 127 | |
| 128 | static int |
| 129 | skipChunk_native(JNIEnv* env, jobject clazz, jobject fdObj, jint bytesToSkip) |
| 130 | { |
| 131 | int fd; |
| 132 | |
| 133 | fd = env->GetIntField(fdObj, s_descriptorField); |
| 134 | |
| 135 | lseek(fd, bytesToSkip, SEEK_CUR); |
| 136 | |
| 137 | return 0; |
| 138 | } |
| 139 | |
| 140 | static int |
| 141 | padding_len(int len) |
| 142 | { |
| 143 | len = len % 4; |
| 144 | return len == 0 ? len : 4 - len; |
| 145 | } |
| 146 | |
| 147 | static int |
| 148 | allocateHeader_native(JNIEnv* env, jobject clazz, jobject headerObj, jobject fdObj) |
| 149 | { |
| 150 | int pos; |
| 151 | jstring nameObj; |
| 152 | int nameLength; |
| 153 | int namePadding; |
| 154 | int headerSize; |
| 155 | int fd; |
| 156 | |
| 157 | fd = env->GetIntField(fdObj, s_descriptorField); |
| 158 | |
| 159 | nameObj = (jstring)env->GetObjectField(headerObj, s_keyPrefixField); |
| 160 | |
| 161 | nameLength = env->GetStringUTFLength(nameObj); |
| 162 | namePadding = padding_len(nameLength); |
| 163 | |
| 164 | headerSize = sizeof(chunk_header_v1) + nameLength + namePadding; |
| 165 | |
| 166 | pos = lseek(fd, 0, SEEK_CUR); |
| 167 | |
| 168 | lseek(fd, headerSize, SEEK_CUR); |
| 169 | |
| 170 | return pos; |
| 171 | } |
| 172 | |
| 173 | static int |
| 174 | writeHeader_native(JNIEnv* env, jobject clazz, jobject headerObj, jobject fdObj, jint pos) |
| 175 | { |
| 176 | int err; |
| 177 | chunk_header_v1 header; |
| 178 | int fd; |
| 179 | int namePadding; |
| 180 | int prevPos; |
| 181 | jstring nameObj; |
| 182 | const char* buf; |
| 183 | |
| 184 | fd = env->GetIntField(fdObj, s_descriptorField); |
| 185 | prevPos = lseek(fd, 0, SEEK_CUR); |
| 186 | |
| 187 | nameObj = (jstring)env->GetObjectField(headerObj, s_keyPrefixField); |
| 188 | header.nameLength = env->GetStringUTFLength(nameObj); |
| 189 | namePadding = padding_len(header.nameLength); |
| 190 | |
| 191 | header.headerSize = sizeof(chunk_header_v1) + header.nameLength + namePadding; |
| 192 | header.version = VERSION_1_HEADER; |
Joe Onorato | 12a4da3 | 2009-06-26 17:18:01 -0400 | [diff] [blame] | 193 | header.dataSize = prevPos - (pos + header.headerSize); |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 194 | |
| 195 | lseek(fd, pos, SEEK_SET); |
| 196 | err = write(fd, &header, sizeof(chunk_header_v1)); |
| 197 | if (err != sizeof(chunk_header_v1)) { |
| 198 | return errno; |
| 199 | } |
| 200 | |
| 201 | buf = env->GetStringUTFChars(nameObj, NULL); |
| 202 | err = write(fd, buf, header.nameLength); |
| 203 | env->ReleaseStringUTFChars(nameObj, buf); |
| 204 | if (err != header.nameLength) { |
| 205 | return errno; |
| 206 | } |
| 207 | |
| 208 | if (namePadding != 0) { |
| 209 | int zero = 0; |
| 210 | err = write(fd, &zero, namePadding); |
| 211 | if (err != namePadding) { |
| 212 | return errno; |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | lseek(fd, prevPos, SEEK_SET); |
| 217 | return 0; |
| 218 | } |
| 219 | |
| 220 | static const JNINativeMethod g_methods[] = { |
| 221 | { "readHeader_native", |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 222 | "(Landroid/app/backup/BackupHelperDispatcher$Header;Ljava/io/FileDescriptor;)I", |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 223 | (void*)readHeader_native }, |
| 224 | { "skipChunk_native", |
| 225 | "(Ljava/io/FileDescriptor;I)I", |
| 226 | (void*)skipChunk_native }, |
| 227 | { "allocateHeader_native", |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 228 | "(Landroid/app/backup/BackupHelperDispatcher$Header;Ljava/io/FileDescriptor;)I", |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 229 | (void*)allocateHeader_native }, |
| 230 | { "writeHeader_native", |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 231 | "(Landroid/app/backup/BackupHelperDispatcher$Header;Ljava/io/FileDescriptor;I)I", |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 232 | (void*)writeHeader_native }, |
| 233 | }; |
| 234 | |
| 235 | int register_android_backup_BackupHelperDispatcher(JNIEnv* env) |
| 236 | { |
| 237 | jclass clazz; |
| 238 | |
| 239 | clazz = env->FindClass("java/io/FileDescriptor"); |
| 240 | LOG_FATAL_IF(clazz == NULL, "Unable to find class java.io.FileDescriptor"); |
| 241 | s_descriptorField = env->GetFieldID(clazz, "descriptor", "I"); |
| 242 | LOG_FATAL_IF(s_descriptorField == NULL, |
| 243 | "Unable to find descriptor field in java.io.FileDescriptor"); |
| 244 | |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 245 | clazz = env->FindClass("android/app/backup/BackupHelperDispatcher$Header"); |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 246 | LOG_FATAL_IF(clazz == NULL, |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 247 | "Unable to find class android.app.backup.BackupHelperDispatcher.Header"); |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 248 | s_chunkSizeField = env->GetFieldID(clazz, "chunkSize", "I"); |
| 249 | LOG_FATAL_IF(s_chunkSizeField == NULL, |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 250 | "Unable to find chunkSize field in android.app.backup.BackupHelperDispatcher.Header"); |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 251 | s_keyPrefixField = env->GetFieldID(clazz, "keyPrefix", "Ljava/lang/String;"); |
| 252 | LOG_FATAL_IF(s_keyPrefixField == NULL, |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 253 | "Unable to find keyPrefix field in android.app.backup.BackupHelperDispatcher.Header"); |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 254 | |
Christopher Tate | 4528186 | 2010-03-05 15:46:30 -0800 | [diff] [blame] | 255 | return AndroidRuntime::registerNativeMethods(env, "android/app/backup/BackupHelperDispatcher", |
Joe Onorato | 4ababd9 | 2009-06-25 18:29:18 -0400 | [diff] [blame] | 256 | g_methods, NELEM(g_methods)); |
| 257 | } |
| 258 | |
| 259 | } |