| /* |
| * Copyright (C) 2007 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #define TRACE_TAG SYNC |
| |
| #include "sysdeps.h" |
| #include "file_sync_service.h" |
| |
| #include <dirent.h> |
| #include <errno.h> |
| #include <linux/xattr.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/stat.h> |
| #include <sys/types.h> |
| #include <sys/xattr.h> |
| #include <unistd.h> |
| #include <utime.h> |
| |
| #include <android-base/file.h> |
| #include <android-base/stringprintf.h> |
| #include <android-base/strings.h> |
| #include <private/android_filesystem_config.h> |
| #include <private/android_logger.h> |
| #include <selinux/android.h> |
| |
| #include "adb.h" |
| #include "adb_io.h" |
| #include "adb_trace.h" |
| #include "adb_utils.h" |
| #include "security_log_tags.h" |
| #include "sysdeps/errno.h" |
| |
| using android::base::StringPrintf; |
| |
| static bool should_use_fs_config(const std::string& path) { |
| // TODO: use fs_config to configure permissions on /data. |
| return android::base::StartsWith(path, "/system/") || |
| android::base::StartsWith(path, "/vendor/") || |
| android::base::StartsWith(path, "/oem/"); |
| } |
| |
| static bool update_capabilities(const char* path, uint64_t capabilities) { |
| if (capabilities == 0) { |
| // Ensure we clean up in case the capabilities weren't 0 in the past. |
| removexattr(path, XATTR_NAME_CAPS); |
| return true; |
| } |
| |
| vfs_cap_data cap_data = {}; |
| cap_data.magic_etc = VFS_CAP_REVISION_2 | VFS_CAP_FLAGS_EFFECTIVE; |
| cap_data.data[0].permitted = (capabilities & 0xffffffff); |
| cap_data.data[0].inheritable = 0; |
| cap_data.data[1].permitted = (capabilities >> 32); |
| cap_data.data[1].inheritable = 0; |
| return setxattr(path, XATTR_NAME_CAPS, &cap_data, sizeof(cap_data), 0) != -1; |
| } |
| |
| static bool secure_mkdirs(const std::string& path) { |
| uid_t uid = -1; |
| gid_t gid = -1; |
| unsigned int mode = 0775; |
| uint64_t capabilities = 0; |
| |
| if (path[0] != '/') return false; |
| |
| std::vector<std::string> path_components = android::base::Split(path, "/"); |
| std::string partial_path; |
| for (const auto& path_component : path_components) { |
| if (partial_path.back() != OS_PATH_SEPARATOR) partial_path += OS_PATH_SEPARATOR; |
| partial_path += path_component; |
| |
| if (should_use_fs_config(partial_path)) { |
| fs_config(partial_path.c_str(), 1, nullptr, &uid, &gid, &mode, &capabilities); |
| } |
| if (adb_mkdir(partial_path.c_str(), mode) == -1) { |
| if (errno != EEXIST) { |
| return false; |
| } |
| } else { |
| if (chown(partial_path.c_str(), uid, gid) == -1) return false; |
| |
| // Not all filesystems support setting SELinux labels. http://b/23530370. |
| selinux_android_restorecon(partial_path.c_str(), 0); |
| |
| if (!update_capabilities(partial_path.c_str(), capabilities)) return false; |
| } |
| } |
| return true; |
| } |
| |
| static bool do_lstat_v1(int s, const char* path) { |
| syncmsg msg = {}; |
| msg.stat_v1.id = ID_LSTAT_V1; |
| |
| struct stat st = {}; |
| lstat(path, &st); |
| msg.stat_v1.mode = st.st_mode; |
| msg.stat_v1.size = st.st_size; |
| msg.stat_v1.time = st.st_mtime; |
| return WriteFdExactly(s, &msg.stat_v1, sizeof(msg.stat_v1)); |
| } |
| |
| static bool do_stat_v2(int s, uint32_t id, const char* path) { |
| syncmsg msg = {}; |
| msg.stat_v2.id = id; |
| |
| decltype(&stat) stat_fn; |
| if (id == ID_STAT_V2) { |
| stat_fn = stat; |
| } else { |
| stat_fn = lstat; |
| } |
| |
| struct stat st = {}; |
| int rc = stat_fn(path, &st); |
| if (rc == -1) { |
| msg.stat_v2.error = errno_to_wire(errno); |
| } else { |
| msg.stat_v2.dev = st.st_dev; |
| msg.stat_v2.ino = st.st_ino; |
| msg.stat_v2.mode = st.st_mode; |
| msg.stat_v2.nlink = st.st_nlink; |
| msg.stat_v2.uid = st.st_uid; |
| msg.stat_v2.gid = st.st_gid; |
| msg.stat_v2.size = st.st_size; |
| msg.stat_v2.atime = st.st_atime; |
| msg.stat_v2.mtime = st.st_mtime; |
| msg.stat_v2.ctime = st.st_ctime; |
| } |
| |
| return WriteFdExactly(s, &msg.stat_v2, sizeof(msg.stat_v2)); |
| } |
| |
| static bool do_list(int s, const char* path) { |
| dirent* de; |
| |
| syncmsg msg; |
| msg.dent.id = ID_DENT; |
| |
| std::unique_ptr<DIR, int(*)(DIR*)> d(opendir(path), closedir); |
| if (!d) goto done; |
| |
| while ((de = readdir(d.get()))) { |
| std::string filename(StringPrintf("%s/%s", path, de->d_name)); |
| |
| struct stat st; |
| if (lstat(filename.c_str(), &st) == 0) { |
| size_t d_name_length = strlen(de->d_name); |
| msg.dent.mode = st.st_mode; |
| msg.dent.size = st.st_size; |
| msg.dent.time = st.st_mtime; |
| msg.dent.namelen = d_name_length; |
| |
| if (!WriteFdExactly(s, &msg.dent, sizeof(msg.dent)) || |
| !WriteFdExactly(s, de->d_name, d_name_length)) { |
| return false; |
| } |
| } |
| } |
| |
| done: |
| msg.dent.id = ID_DONE; |
| msg.dent.mode = 0; |
| msg.dent.size = 0; |
| msg.dent.time = 0; |
| msg.dent.namelen = 0; |
| return WriteFdExactly(s, &msg.dent, sizeof(msg.dent)); |
| } |
| |
| // Make sure that SendFail from adb_io.cpp isn't accidentally used in this file. |
| #pragma GCC poison SendFail |
| |
| static bool SendSyncFail(int fd, const std::string& reason) { |
| D("sync: failure: %s", reason.c_str()); |
| |
| syncmsg msg; |
| msg.data.id = ID_FAIL; |
| msg.data.size = reason.size(); |
| return WriteFdExactly(fd, &msg.data, sizeof(msg.data)) && WriteFdExactly(fd, reason); |
| } |
| |
| static bool SendSyncFailErrno(int fd, const std::string& reason) { |
| return SendSyncFail(fd, StringPrintf("%s: %s", reason.c_str(), strerror(errno))); |
| } |
| |
| static bool handle_send_file(int s, const char* path, uid_t uid, gid_t gid, uint64_t capabilities, |
| mode_t mode, std::vector<char>& buffer, bool do_unlink) { |
| syncmsg msg; |
| unsigned int timestamp = 0; |
| |
| __android_log_security_bswrite(SEC_TAG_ADB_SEND_FILE, path); |
| |
| int fd = adb_open_mode(path, O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC, mode); |
| |
| if (posix_fadvise(fd, 0, 0, POSIX_FADV_SEQUENTIAL | POSIX_FADV_NOREUSE | POSIX_FADV_WILLNEED) < |
| 0) { |
| D("[ Failed to fadvise: %d ]", errno); |
| } |
| |
| if (fd < 0 && errno == ENOENT) { |
| if (!secure_mkdirs(android::base::Dirname(path))) { |
| SendSyncFailErrno(s, "secure_mkdirs failed"); |
| goto fail; |
| } |
| fd = adb_open_mode(path, O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC, mode); |
| } |
| if (fd < 0 && errno == EEXIST) { |
| fd = adb_open_mode(path, O_WRONLY | O_CLOEXEC, mode); |
| } |
| if (fd < 0) { |
| SendSyncFailErrno(s, "couldn't create file"); |
| goto fail; |
| } else { |
| if (fchown(fd, uid, gid) == -1) { |
| SendSyncFailErrno(s, "fchown failed"); |
| goto fail; |
| } |
| |
| // Not all filesystems support setting SELinux labels. http://b/23530370. |
| selinux_android_restorecon(path, 0); |
| |
| // fchown clears the setuid bit - restore it if present. |
| // Ignore the result of calling fchmod. It's not supported |
| // by all filesystems, so we don't check for success. b/12441485 |
| fchmod(fd, mode); |
| } |
| |
| while (true) { |
| if (!ReadFdExactly(s, &msg.data, sizeof(msg.data))) goto fail; |
| |
| if (msg.data.id != ID_DATA) { |
| if (msg.data.id == ID_DONE) { |
| timestamp = msg.data.size; |
| break; |
| } |
| SendSyncFail(s, "invalid data message"); |
| goto abort; |
| } |
| |
| if (msg.data.size > buffer.size()) { // TODO: resize buffer? |
| SendSyncFail(s, "oversize data message"); |
| goto abort; |
| } |
| |
| if (!ReadFdExactly(s, &buffer[0], msg.data.size)) goto abort; |
| |
| if (!WriteFdExactly(fd, &buffer[0], msg.data.size)) { |
| SendSyncFailErrno(s, "write failed"); |
| goto fail; |
| } |
| } |
| |
| adb_close(fd); |
| |
| if (!update_capabilities(path, capabilities)) { |
| SendSyncFailErrno(s, "update_capabilities failed"); |
| goto fail; |
| } |
| |
| utimbuf u; |
| u.actime = timestamp; |
| u.modtime = timestamp; |
| utime(path, &u); |
| |
| msg.status.id = ID_OKAY; |
| msg.status.msglen = 0; |
| return WriteFdExactly(s, &msg.status, sizeof(msg.status)); |
| |
| fail: |
| // If there's a problem on the device, we'll send an ID_FAIL message and |
| // close the socket. Unfortunately the kernel will sometimes throw that |
| // data away if the other end keeps writing without reading (which is |
| // the case with old versions of adb). To maintain compatibility, keep |
| // reading and throwing away ID_DATA packets until the other side notices |
| // that we've reported an error. |
| while (true) { |
| if (!ReadFdExactly(s, &msg.data, sizeof(msg.data))) break; |
| |
| if (msg.data.id == ID_DONE) { |
| break; |
| } else if (msg.data.id != ID_DATA) { |
| char id[5]; |
| memcpy(id, &msg.data.id, sizeof(msg.data.id)); |
| id[4] = '\0'; |
| D("handle_send_fail received unexpected id '%s' during failure", id); |
| break; |
| } |
| |
| if (msg.data.size > buffer.size()) { |
| D("handle_send_fail received oversized packet of length '%u' during failure", |
| msg.data.size); |
| break; |
| } |
| |
| if (!ReadFdExactly(s, &buffer[0], msg.data.size)) break; |
| } |
| |
| abort: |
| if (fd >= 0) adb_close(fd); |
| if (do_unlink) adb_unlink(path); |
| return false; |
| } |
| |
| #if defined(_WIN32) |
| extern bool handle_send_link(int s, const std::string& path, std::vector<char>& buffer) __attribute__((error("no symlinks on Windows"))); |
| #else |
| static bool handle_send_link(int s, const std::string& path, std::vector<char>& buffer) { |
| syncmsg msg; |
| unsigned int len; |
| int ret; |
| |
| if (!ReadFdExactly(s, &msg.data, sizeof(msg.data))) return false; |
| |
| if (msg.data.id != ID_DATA) { |
| SendSyncFail(s, "invalid data message: expected ID_DATA"); |
| return false; |
| } |
| |
| len = msg.data.size; |
| if (len > buffer.size()) { // TODO: resize buffer? |
| SendSyncFail(s, "oversize data message"); |
| return false; |
| } |
| if (!ReadFdExactly(s, &buffer[0], len)) return false; |
| |
| ret = symlink(&buffer[0], path.c_str()); |
| if (ret && errno == ENOENT) { |
| if (!secure_mkdirs(android::base::Dirname(path))) { |
| SendSyncFailErrno(s, "secure_mkdirs failed"); |
| return false; |
| } |
| ret = symlink(&buffer[0], path.c_str()); |
| } |
| if (ret) { |
| SendSyncFailErrno(s, "symlink failed"); |
| return false; |
| } |
| |
| if (!ReadFdExactly(s, &msg.data, sizeof(msg.data))) return false; |
| |
| if (msg.data.id == ID_DONE) { |
| msg.status.id = ID_OKAY; |
| msg.status.msglen = 0; |
| if (!WriteFdExactly(s, &msg.status, sizeof(msg.status))) return false; |
| } else { |
| SendSyncFail(s, "invalid data message: expected ID_DONE"); |
| return false; |
| } |
| |
| return true; |
| } |
| #endif |
| |
| static bool do_send(int s, const std::string& spec, std::vector<char>& buffer) { |
| // 'spec' is of the form "/some/path,0755". Break it up. |
| size_t comma = spec.find_last_of(','); |
| if (comma == std::string::npos) { |
| SendSyncFail(s, "missing , in ID_SEND"); |
| return false; |
| } |
| |
| std::string path = spec.substr(0, comma); |
| |
| errno = 0; |
| mode_t mode = strtoul(spec.substr(comma + 1).c_str(), nullptr, 0); |
| if (errno != 0) { |
| SendSyncFail(s, "bad mode"); |
| return false; |
| } |
| |
| // Don't delete files before copying if they are not "regular" or symlinks. |
| struct stat st; |
| bool do_unlink = (lstat(path.c_str(), &st) == -1) || S_ISREG(st.st_mode) || S_ISLNK(st.st_mode); |
| if (do_unlink) { |
| adb_unlink(path.c_str()); |
| } |
| |
| if (S_ISLNK(mode)) { |
| return handle_send_link(s, path.c_str(), buffer); |
| } |
| |
| // Copy user permission bits to "group" and "other" permissions. |
| mode &= 0777; |
| mode |= ((mode >> 3) & 0070); |
| mode |= ((mode >> 3) & 0007); |
| |
| uid_t uid = -1; |
| gid_t gid = -1; |
| uint64_t capabilities = 0; |
| if (should_use_fs_config(path)) { |
| unsigned int broken_api_hack = mode; |
| fs_config(path.c_str(), 0, nullptr, &uid, &gid, &broken_api_hack, &capabilities); |
| mode = broken_api_hack; |
| } |
| return handle_send_file(s, path.c_str(), uid, gid, capabilities, mode, buffer, do_unlink); |
| } |
| |
| static bool do_recv(int s, const char* path, std::vector<char>& buffer) { |
| __android_log_security_bswrite(SEC_TAG_ADB_RECV_FILE, path); |
| |
| int fd = adb_open(path, O_RDONLY | O_CLOEXEC); |
| if (fd < 0) { |
| SendSyncFailErrno(s, "open failed"); |
| return false; |
| } |
| |
| if (posix_fadvise(fd, 0, 0, POSIX_FADV_SEQUENTIAL | POSIX_FADV_NOREUSE) < 0) { |
| D("[ Failed to fadvise: %d ]", errno); |
| } |
| |
| syncmsg msg; |
| msg.data.id = ID_DATA; |
| while (true) { |
| int r = adb_read(fd, &buffer[0], buffer.size() - sizeof(msg.data)); |
| if (r <= 0) { |
| if (r == 0) break; |
| SendSyncFailErrno(s, "read failed"); |
| adb_close(fd); |
| return false; |
| } |
| msg.data.size = r; |
| if (!WriteFdExactly(s, &msg.data, sizeof(msg.data)) || !WriteFdExactly(s, &buffer[0], r)) { |
| adb_close(fd); |
| return false; |
| } |
| } |
| |
| adb_close(fd); |
| |
| msg.data.id = ID_DONE; |
| msg.data.size = 0; |
| return WriteFdExactly(s, &msg.data, sizeof(msg.data)); |
| } |
| |
| static const char* sync_id_to_name(uint32_t id) { |
| switch (id) { |
| case ID_LSTAT_V1: |
| return "lstat_v1"; |
| case ID_LSTAT_V2: |
| return "lstat_v2"; |
| case ID_STAT_V2: |
| return "stat_v2"; |
| case ID_LIST: |
| return "list"; |
| case ID_SEND: |
| return "send"; |
| case ID_RECV: |
| return "recv"; |
| case ID_QUIT: |
| return "quit"; |
| default: |
| return "???"; |
| } |
| } |
| |
| static bool handle_sync_command(int fd, std::vector<char>& buffer) { |
| D("sync: waiting for request"); |
| |
| ATRACE_CALL(); |
| SyncRequest request; |
| if (!ReadFdExactly(fd, &request, sizeof(request))) { |
| SendSyncFail(fd, "command read failure"); |
| return false; |
| } |
| size_t path_length = request.path_length; |
| if (path_length > 1024) { |
| SendSyncFail(fd, "path too long"); |
| return false; |
| } |
| char name[1025]; |
| if (!ReadFdExactly(fd, name, path_length)) { |
| SendSyncFail(fd, "filename read failure"); |
| return false; |
| } |
| name[path_length] = 0; |
| |
| std::string id_name = sync_id_to_name(request.id); |
| std::string trace_name = StringPrintf("%s(%s)", id_name.c_str(), name); |
| ATRACE_NAME(trace_name.c_str()); |
| |
| D("sync: %s('%s')", id_name.c_str(), name); |
| switch (request.id) { |
| case ID_LSTAT_V1: |
| if (!do_lstat_v1(fd, name)) return false; |
| break; |
| case ID_LSTAT_V2: |
| case ID_STAT_V2: |
| if (!do_stat_v2(fd, request.id, name)) return false; |
| break; |
| case ID_LIST: |
| if (!do_list(fd, name)) return false; |
| break; |
| case ID_SEND: |
| if (!do_send(fd, name, buffer)) return false; |
| break; |
| case ID_RECV: |
| if (!do_recv(fd, name, buffer)) return false; |
| break; |
| case ID_QUIT: |
| return false; |
| default: |
| SendSyncFail(fd, StringPrintf("unknown command %08x", request.id)); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| void file_sync_service(int fd, void*) { |
| std::vector<char> buffer(SYNC_DATA_MAX); |
| |
| while (handle_sync_command(fd, buffer)) { |
| } |
| |
| D("sync: done"); |
| adb_close(fd); |
| } |