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 <stdio.h> 18 #include <stdlib.h> 19 #include <fcntl.h> 20 #include <unistd.h> 21 #include <errno.h> 22 #include <string.h> 23 #include <dirent.h> 24 #include <errno.h> 25 #include <fcntl.h> 26 27 #include <sys/types.h> 28 #include <sys/stat.h> 29 #include <sys/types.h> 30 #include <sys/mman.h> 31 #include <sys/mount.h> 32 #include <sys/wait.h> 33 #include <linux/fs.h> 34 #include <sys/ioctl.h> 35 36 #include <linux/kdev_t.h> 37 38 #define LOG_TAG "Vold" 39 40 #include <android-base/logging.h> 41 #include <android-base/stringprintf.h> 42 #include <cutils/log.h> 43 #include <cutils/properties.h> 44 #include <selinux/selinux.h> 45 46 #include <logwrap/logwrap.h> 47 48 #include "Vfat.h" 49 #include "Utils.h" 50 #include "VoldUtil.h" 51 52 using android::base::StringPrintf; 53 54 namespace android { 55 namespace vold { 56 namespace vfat { 57 58 static const char* kMkfsPath = "/system/bin/newfs_msdos"; 59 static const char* kFsckPath = "/system/bin/fsck_msdos"; 60 61 bool IsSupported() { 62 return access(kMkfsPath, X_OK) == 0 63 && access(kFsckPath, X_OK) == 0 64 && IsFilesystemSupported("vfat"); 65 } 66 67 status_t Check(const std::string& source) { 68 if (access(kFsckPath, X_OK)) { 69 SLOGW("Skipping fs checks\n"); 70 return 0; 71 } 72 73 int pass = 1; 74 int rc = 0; 75 do { 76 std::vector<std::string> cmd; 77 cmd.push_back(kFsckPath); 78 cmd.push_back("-p"); 79 cmd.push_back("-f"); 80 cmd.push_back(source); 81 82 // Fat devices are currently always untrusted 83 rc = ForkExecvp(cmd, sFsckUntrustedContext); 84 85 if (rc < 0) { 86 SLOGE("Filesystem check failed due to logwrap error"); 87 errno = EIO; 88 return -1; 89 } 90 91 switch(rc) { 92 case 0: 93 SLOGI("Filesystem check completed OK"); 94 return 0; 95 96 case 2: 97 SLOGE("Filesystem check failed (not a FAT filesystem)"); 98 errno = ENODATA; 99 return -1; 100 101 case 4: 102 if (pass++ <= 3) { 103 SLOGW("Filesystem modified - rechecking (pass %d)", 104 pass); 105 continue; 106 } 107 SLOGE("Failing check after too many rechecks"); 108 errno = EIO; 109 return -1; 110 111 case 8: 112 SLOGE("Filesystem check failed (no filesystem)"); 113 errno = ENODATA; 114 return -1; 115 116 default: 117 SLOGE("Filesystem check failed (unknown exit code %d)", rc); 118 errno = EIO; 119 return -1; 120 } 121 } while (0); 122 123 return 0; 124 } 125 126 status_t Mount(const std::string& source, const std::string& target, bool ro, 127 bool remount, bool executable, int ownerUid, int ownerGid, int permMask, 128 bool createLost) { 129 int rc; 130 unsigned long flags; 131 char mountData[255]; 132 133 const char* c_source = source.c_str(); 134 const char* c_target = target.c_str(); 135 136 flags = MS_NODEV | MS_NOSUID | MS_DIRSYNC; 137 138 flags |= (executable ? 0 : MS_NOEXEC); 139 flags |= (ro ? MS_RDONLY : 0); 140 flags |= (remount ? MS_REMOUNT : 0); 141 142 sprintf(mountData, 143 "utf8,uid=%d,gid=%d,fmask=%o,dmask=%o,shortname=mixed", 144 ownerUid, ownerGid, permMask, permMask); 145 146 rc = mount(c_source, c_target, "vfat", flags, mountData); 147 148 if (rc && errno == EROFS) { 149 SLOGE("%s appears to be a read only filesystem - retrying mount RO", c_source); 150 flags |= MS_RDONLY; 151 rc = mount(c_source, c_target, "vfat", flags, mountData); 152 } 153 154 if (rc == 0 && createLost) { 155 char *lost_path; 156 asprintf(&lost_path, "%s/LOST.DIR", c_target); 157 if (access(lost_path, F_OK)) { 158 /* 159 * Create a LOST.DIR in the root so we have somewhere to put 160 * lost cluster chains (fsck_msdos doesn't currently do this) 161 */ 162 if (mkdir(lost_path, 0755)) { 163 SLOGE("Unable to create LOST.DIR (%s)", strerror(errno)); 164 } 165 } 166 free(lost_path); 167 } 168 169 return rc; 170 } 171 172 status_t Format(const std::string& source, unsigned long numSectors) { 173 std::vector<std::string> cmd; 174 cmd.push_back(kMkfsPath); 175 cmd.push_back("-F"); 176 cmd.push_back("32"); 177 cmd.push_back("-O"); 178 cmd.push_back("android"); 179 cmd.push_back("-c"); 180 cmd.push_back("64"); 181 cmd.push_back("-A"); 182 183 if (numSectors) { 184 cmd.push_back("-s"); 185 cmd.push_back(StringPrintf("%lu", numSectors)); 186 } 187 188 cmd.push_back(source); 189 190 int rc = ForkExecvp(cmd); 191 if (rc < 0) { 192 SLOGE("Filesystem format failed due to logwrap error"); 193 errno = EIO; 194 return -1; 195 } 196 197 if (rc == 0) { 198 SLOGI("Filesystem formatted OK"); 199 return 0; 200 } else { 201 SLOGE("Format failed (unknown exit code %d)", rc); 202 errno = EIO; 203 return -1; 204 } 205 return 0; 206 } 207 208 } // namespace vfat 209 } // namespace vold 210 } // namespace android 211
