Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2021 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 | use anyhow::Result; |
| 18 | use log::error; |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 19 | use nix::{ |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 20 | dir::Dir, errno::Errno, fcntl::openat, fcntl::OFlag, sys::stat::fchmod, sys::stat::mkdirat, |
| 21 | sys::stat::mode_t, sys::stat::Mode, sys::statvfs::statvfs, sys::statvfs::Statvfs, |
| 22 | unistd::unlinkat, unistd::UnlinkatFlags, |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 23 | }; |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 24 | use std::cmp::min; |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 25 | use std::collections::{btree_map, BTreeMap}; |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 26 | use std::convert::TryInto; |
| 27 | use std::fs::File; |
| 28 | use std::io; |
| 29 | use std::os::unix::fs::FileExt; |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 30 | use std::os::unix::io::{AsRawFd, FromRawFd, RawFd}; |
| 31 | use std::path::{Component, Path, PathBuf, MAIN_SEPARATOR}; |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 32 | use std::sync::{Arc, Mutex}; |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 33 | |
| 34 | use crate::fsverity; |
| 35 | use authfs_aidl_interface::aidl::com::android::virt::fs::IVirtFdService::{ |
Victor Hsieh | f7fc3d3 | 2021-11-22 10:20:33 -0800 | [diff] [blame] | 36 | BnVirtFdService, FsStat::FsStat, IVirtFdService, MAX_REQUESTING_DATA, |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 37 | }; |
| 38 | use authfs_aidl_interface::binder::{ |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 39 | BinderFeatures, ExceptionCode, Interface, Result as BinderResult, Status, StatusCode, Strong, |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 40 | }; |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 41 | use binder_common::{new_binder_exception, new_binder_service_specific_error}; |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 42 | |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 43 | /// Bitflags of forbidden file mode, e.g. setuid, setgid and sticky bit. |
| 44 | const FORBIDDEN_MODES: Mode = Mode::from_bits_truncate(!0o777); |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 45 | |
| 46 | /// Configuration of a file descriptor to be served/exposed/shared. |
| 47 | pub enum FdConfig { |
| 48 | /// A read-only file to serve by this server. The file is supposed to be verifiable with the |
| 49 | /// associated fs-verity metadata. |
| 50 | Readonly { |
| 51 | /// The file to read from. fs-verity metadata can be retrieved from this file's FD. |
| 52 | file: File, |
| 53 | |
| 54 | /// Alternative Merkle tree stored in another file. |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 55 | /// TODO(205987437): Replace with .fsv_meta file. |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 56 | alt_merkle_tree: Option<File>, |
| 57 | |
| 58 | /// Alternative signature stored in another file. |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 59 | /// TODO(205987437): Replace with .fsv_meta file. |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 60 | alt_signature: Option<File>, |
| 61 | }, |
| 62 | |
| 63 | /// A readable/writable file to serve by this server. This backing file should just be a |
| 64 | /// regular file and does not have any specific property. |
| 65 | ReadWrite(File), |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 66 | |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 67 | /// A read-only directory to serve by this server. |
| 68 | InputDir(Dir), |
| 69 | |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 70 | /// A writable directory to serve by this server. |
| 71 | OutputDir(Dir), |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 72 | } |
| 73 | |
| 74 | pub struct FdService { |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 75 | /// A pool of opened files and directories, which can be looked up by the FD number. |
| 76 | fd_pool: Arc<Mutex<BTreeMap<i32, FdConfig>>>, |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 77 | } |
| 78 | |
| 79 | impl FdService { |
| 80 | pub fn new_binder(fd_pool: BTreeMap<i32, FdConfig>) -> Strong<dyn IVirtFdService> { |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 81 | BnVirtFdService::new_binder( |
| 82 | FdService { fd_pool: Arc::new(Mutex::new(fd_pool)) }, |
| 83 | BinderFeatures::default(), |
| 84 | ) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 85 | } |
| 86 | |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 87 | /// Handles the requesting file `id` with `handle_fn` if it is in the FD pool. This function |
| 88 | /// returns whatever `handle_fn` returns. |
| 89 | fn handle_fd<F, R>(&self, id: i32, handle_fn: F) -> BinderResult<R> |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 90 | where |
| 91 | F: FnOnce(&FdConfig) -> BinderResult<R>, |
| 92 | { |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 93 | let fd_pool = self.fd_pool.lock().unwrap(); |
| 94 | let fd_config = fd_pool.get(&id).ok_or_else(|| new_errno_error(Errno::EBADF))?; |
| 95 | handle_fn(fd_config) |
| 96 | } |
| 97 | |
| 98 | /// Inserts a new FD and corresponding `FdConfig` created by `create_fn` to the FD pool, then |
| 99 | /// returns the new FD number. |
| 100 | fn insert_new_fd<F>(&self, fd: i32, create_fn: F) -> BinderResult<i32> |
| 101 | where |
| 102 | F: FnOnce(&mut FdConfig) -> BinderResult<(i32, FdConfig)>, |
| 103 | { |
| 104 | let mut fd_pool = self.fd_pool.lock().unwrap(); |
Chris Wailes | 641fc4a | 2021-12-01 15:03:21 -0800 | [diff] [blame] | 105 | let fd_config = fd_pool.get_mut(&fd).ok_or_else(|| new_errno_error(Errno::EBADF))?; |
| 106 | let (new_fd, new_fd_config) = create_fn(fd_config)?; |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 107 | if let btree_map::Entry::Vacant(entry) = fd_pool.entry(new_fd) { |
| 108 | entry.insert(new_fd_config); |
| 109 | Ok(new_fd) |
| 110 | } else { |
| 111 | Err(new_binder_exception( |
| 112 | ExceptionCode::ILLEGAL_STATE, |
| 113 | format!("The newly created FD {} is already in the pool unexpectedly", new_fd), |
| 114 | )) |
| 115 | } |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 116 | } |
| 117 | } |
| 118 | |
| 119 | impl Interface for FdService {} |
| 120 | |
| 121 | impl IVirtFdService for FdService { |
| 122 | fn readFile(&self, id: i32, offset: i64, size: i32) -> BinderResult<Vec<u8>> { |
| 123 | let size: usize = validate_and_cast_size(size)?; |
| 124 | let offset: u64 = validate_and_cast_offset(offset)?; |
| 125 | |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 126 | self.handle_fd(id, |config| match config { |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 127 | FdConfig::Readonly { file, .. } | FdConfig::ReadWrite(file) => { |
| 128 | read_into_buf(file, size, offset).map_err(|e| { |
| 129 | error!("readFile: read error: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 130 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 131 | }) |
| 132 | } |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 133 | FdConfig::InputDir(_) | FdConfig::OutputDir(_) => Err(new_errno_error(Errno::EISDIR)), |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 134 | }) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 135 | } |
| 136 | |
| 137 | fn readFsverityMerkleTree(&self, id: i32, offset: i64, size: i32) -> BinderResult<Vec<u8>> { |
| 138 | let size: usize = validate_and_cast_size(size)?; |
| 139 | let offset: u64 = validate_and_cast_offset(offset)?; |
| 140 | |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 141 | self.handle_fd(id, |config| match config { |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 142 | FdConfig::Readonly { file, alt_merkle_tree, .. } => { |
| 143 | if let Some(tree_file) = &alt_merkle_tree { |
| 144 | read_into_buf(tree_file, size, offset).map_err(|e| { |
| 145 | error!("readFsverityMerkleTree: read error: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 146 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 147 | }) |
| 148 | } else { |
| 149 | let mut buf = vec![0; size]; |
| 150 | let s = fsverity::read_merkle_tree(file.as_raw_fd(), offset, &mut buf) |
| 151 | .map_err(|e| { |
| 152 | error!("readFsverityMerkleTree: failed to retrieve merkle tree: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 153 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 154 | })?; |
| 155 | debug_assert!(s <= buf.len(), "Shouldn't return more bytes than asked"); |
| 156 | buf.truncate(s); |
| 157 | Ok(buf) |
| 158 | } |
| 159 | } |
| 160 | FdConfig::ReadWrite(_file) => { |
| 161 | // For a writable file, Merkle tree is not expected to be served since Auth FS |
| 162 | // doesn't trust it anyway. Auth FS may keep the Merkle tree privately for its own |
| 163 | // use. |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 164 | Err(new_errno_error(Errno::ENOSYS)) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 165 | } |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 166 | FdConfig::InputDir(_) | FdConfig::OutputDir(_) => Err(new_errno_error(Errno::EISDIR)), |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 167 | }) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 168 | } |
| 169 | |
| 170 | fn readFsveritySignature(&self, id: i32) -> BinderResult<Vec<u8>> { |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 171 | self.handle_fd(id, |config| match config { |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 172 | FdConfig::Readonly { file, alt_signature, .. } => { |
| 173 | if let Some(sig_file) = &alt_signature { |
| 174 | // Supposedly big enough buffer size to store signature. |
| 175 | let size = MAX_REQUESTING_DATA as usize; |
| 176 | let offset = 0; |
| 177 | read_into_buf(sig_file, size, offset).map_err(|e| { |
| 178 | error!("readFsveritySignature: read error: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 179 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 180 | }) |
| 181 | } else { |
| 182 | let mut buf = vec![0; MAX_REQUESTING_DATA as usize]; |
| 183 | let s = fsverity::read_signature(file.as_raw_fd(), &mut buf).map_err(|e| { |
| 184 | error!("readFsverityMerkleTree: failed to retrieve merkle tree: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 185 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 186 | })?; |
| 187 | debug_assert!(s <= buf.len(), "Shouldn't return more bytes than asked"); |
| 188 | buf.truncate(s); |
| 189 | Ok(buf) |
| 190 | } |
| 191 | } |
| 192 | FdConfig::ReadWrite(_file) => { |
| 193 | // There is no signature for a writable file. |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 194 | Err(new_errno_error(Errno::ENOSYS)) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 195 | } |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 196 | FdConfig::InputDir(_) | FdConfig::OutputDir(_) => Err(new_errno_error(Errno::EISDIR)), |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 197 | }) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 198 | } |
| 199 | |
| 200 | fn writeFile(&self, id: i32, buf: &[u8], offset: i64) -> BinderResult<i32> { |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 201 | self.handle_fd(id, |config| match config { |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 202 | FdConfig::Readonly { .. } => Err(StatusCode::INVALID_OPERATION.into()), |
| 203 | FdConfig::ReadWrite(file) => { |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 204 | let offset: u64 = offset.try_into().map_err(|_| new_errno_error(Errno::EINVAL))?; |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 205 | // Check buffer size just to make `as i32` safe below. |
| 206 | if buf.len() > i32::MAX as usize { |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 207 | return Err(new_errno_error(Errno::EOVERFLOW)); |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 208 | } |
| 209 | Ok(file.write_at(buf, offset).map_err(|e| { |
| 210 | error!("writeFile: write error: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 211 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 212 | })? as i32) |
| 213 | } |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 214 | FdConfig::InputDir(_) | FdConfig::OutputDir(_) => Err(new_errno_error(Errno::EISDIR)), |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 215 | }) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 216 | } |
| 217 | |
| 218 | fn resize(&self, id: i32, size: i64) -> BinderResult<()> { |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 219 | self.handle_fd(id, |config| match config { |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 220 | FdConfig::Readonly { .. } => Err(StatusCode::INVALID_OPERATION.into()), |
| 221 | FdConfig::ReadWrite(file) => { |
| 222 | if size < 0 { |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 223 | return Err(new_errno_error(Errno::EINVAL)); |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 224 | } |
| 225 | file.set_len(size as u64).map_err(|e| { |
| 226 | error!("resize: set_len error: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 227 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 228 | }) |
| 229 | } |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 230 | FdConfig::InputDir(_) | FdConfig::OutputDir(_) => Err(new_errno_error(Errno::EISDIR)), |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 231 | }) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 232 | } |
| 233 | |
| 234 | fn getFileSize(&self, id: i32) -> BinderResult<i64> { |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 235 | self.handle_fd(id, |config| match config { |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 236 | FdConfig::Readonly { file, .. } => { |
| 237 | let size = file |
| 238 | .metadata() |
| 239 | .map_err(|e| { |
| 240 | error!("getFileSize error: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 241 | new_errno_error(Errno::EIO) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 242 | })? |
| 243 | .len(); |
| 244 | Ok(size.try_into().map_err(|e| { |
| 245 | error!("getFileSize: File too large: {}", e); |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 246 | new_errno_error(Errno::EFBIG) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 247 | })?) |
| 248 | } |
| 249 | FdConfig::ReadWrite(_file) => { |
| 250 | // Content and metadata of a writable file needs to be tracked by authfs, since |
| 251 | // fd_server isn't considered trusted. So there is no point to support getFileSize |
| 252 | // for a writable file. |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 253 | Err(new_errno_error(Errno::ENOSYS)) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 254 | } |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 255 | FdConfig::InputDir(_) | FdConfig::OutputDir(_) => Err(new_errno_error(Errno::EISDIR)), |
| 256 | }) |
| 257 | } |
| 258 | |
Victor Hsieh | dd99b46 | 2021-12-02 17:36:15 -0800 | [diff] [blame] | 259 | fn openFileInDirectory(&self, dir_fd: i32, file_path: &str) -> BinderResult<i32> { |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 260 | let path_buf = PathBuf::from(file_path); |
| 261 | // Checks if the path is a simple, related path. |
| 262 | if path_buf.components().any(|c| !matches!(c, Component::Normal(_))) { |
| 263 | return Err(new_errno_error(Errno::EINVAL)); |
| 264 | } |
| 265 | |
Victor Hsieh | dd99b46 | 2021-12-02 17:36:15 -0800 | [diff] [blame] | 266 | self.insert_new_fd(dir_fd, |config| match config { |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 267 | FdConfig::InputDir(dir) => { |
| 268 | let file = open_readonly_at(dir.as_raw_fd(), &path_buf).map_err(new_errno_error)?; |
| 269 | |
| 270 | // TODO(205987437): Provide the corresponding ".fsv_meta" file when it's created. |
| 271 | Ok(( |
| 272 | file.as_raw_fd(), |
| 273 | FdConfig::Readonly { file, alt_merkle_tree: None, alt_signature: None }, |
| 274 | )) |
| 275 | } |
| 276 | FdConfig::OutputDir(_) => { |
| 277 | Err(new_errno_error(Errno::ENOSYS)) // TODO: Implement when needed |
| 278 | } |
| 279 | _ => Err(new_errno_error(Errno::ENOTDIR)), |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 280 | }) |
| 281 | } |
| 282 | |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 283 | fn createFileInDirectory(&self, dir_fd: i32, basename: &str, mode: i32) -> BinderResult<i32> { |
Victor Hsieh | dd99b46 | 2021-12-02 17:36:15 -0800 | [diff] [blame] | 284 | validate_basename(basename)?; |
| 285 | |
| 286 | self.insert_new_fd(dir_fd, |config| match config { |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 287 | FdConfig::InputDir(_) => Err(new_errno_error(Errno::EACCES)), |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 288 | FdConfig::OutputDir(dir) => { |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 289 | let mode = validate_file_mode(mode)?; |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 290 | let new_fd = openat( |
| 291 | dir.as_raw_fd(), |
| 292 | basename, |
| 293 | // TODO(205172873): handle the case when the file already exist, e.g. truncate |
| 294 | // or fail, and possibly allow the client to specify. For now, always truncate. |
| 295 | OFlag::O_CREAT | OFlag::O_RDWR | OFlag::O_TRUNC, |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 296 | mode, |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 297 | ) |
| 298 | .map_err(new_errno_error)?; |
| 299 | // SAFETY: new_fd is just created and not an error. |
| 300 | let new_file = unsafe { File::from_raw_fd(new_fd) }; |
| 301 | Ok((new_fd, FdConfig::ReadWrite(new_file))) |
| 302 | } |
| 303 | _ => Err(new_errno_error(Errno::ENOTDIR)), |
| 304 | }) |
| 305 | } |
| 306 | |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 307 | fn createDirectoryInDirectory( |
| 308 | &self, |
| 309 | dir_fd: i32, |
| 310 | basename: &str, |
| 311 | mode: i32, |
| 312 | ) -> BinderResult<i32> { |
Victor Hsieh | dd99b46 | 2021-12-02 17:36:15 -0800 | [diff] [blame] | 313 | validate_basename(basename)?; |
| 314 | |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 315 | self.insert_new_fd(dir_fd, |config| match config { |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 316 | FdConfig::InputDir(_) => Err(new_errno_error(Errno::EACCES)), |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 317 | FdConfig::OutputDir(_) => { |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 318 | let mode = validate_file_mode(mode)?; |
| 319 | mkdirat(dir_fd, basename, mode).map_err(new_errno_error)?; |
Victor Hsieh | 4563623 | 2021-10-15 17:52:51 -0700 | [diff] [blame] | 320 | let new_dir = Dir::openat( |
| 321 | dir_fd, |
| 322 | basename, |
| 323 | OFlag::O_DIRECTORY | OFlag::O_RDONLY, |
| 324 | Mode::empty(), |
| 325 | ) |
| 326 | .map_err(new_errno_error)?; |
| 327 | Ok((new_dir.as_raw_fd(), FdConfig::OutputDir(new_dir))) |
| 328 | } |
| 329 | _ => Err(new_errno_error(Errno::ENOTDIR)), |
Victor Hsieh | c85e4ef | 2021-10-18 15:28:53 -0700 | [diff] [blame] | 330 | }) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 331 | } |
Victor Hsieh | f7fc3d3 | 2021-11-22 10:20:33 -0800 | [diff] [blame] | 332 | |
Victor Hsieh | dd99b46 | 2021-12-02 17:36:15 -0800 | [diff] [blame] | 333 | fn deleteFile(&self, dir_fd: i32, basename: &str) -> BinderResult<()> { |
| 334 | validate_basename(basename)?; |
| 335 | |
| 336 | self.handle_fd(dir_fd, |config| match config { |
| 337 | FdConfig::OutputDir(_dir) => { |
| 338 | unlinkat(Some(dir_fd), basename, UnlinkatFlags::NoRemoveDir) |
| 339 | .map_err(new_errno_error)?; |
| 340 | Ok(()) |
| 341 | } |
| 342 | FdConfig::InputDir(_) => Err(new_errno_error(Errno::EACCES)), |
| 343 | _ => Err(new_errno_error(Errno::ENOTDIR)), |
| 344 | }) |
| 345 | } |
| 346 | |
| 347 | fn deleteDirectory(&self, dir_fd: i32, basename: &str) -> BinderResult<()> { |
| 348 | validate_basename(basename)?; |
| 349 | |
| 350 | self.handle_fd(dir_fd, |config| match config { |
| 351 | FdConfig::OutputDir(_dir) => { |
| 352 | unlinkat(Some(dir_fd), basename, UnlinkatFlags::RemoveDir) |
| 353 | .map_err(new_errno_error)?; |
| 354 | Ok(()) |
| 355 | } |
| 356 | FdConfig::InputDir(_) => Err(new_errno_error(Errno::EACCES)), |
| 357 | _ => Err(new_errno_error(Errno::ENOTDIR)), |
| 358 | }) |
| 359 | } |
| 360 | |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 361 | fn chmod(&self, fd: i32, mode: i32) -> BinderResult<()> { |
| 362 | self.handle_fd(fd, |config| match config { |
| 363 | FdConfig::ReadWrite(_) | FdConfig::OutputDir(_) => { |
| 364 | let mode = validate_file_mode(mode)?; |
| 365 | fchmod(fd, mode).map_err(new_errno_error) |
| 366 | } |
| 367 | _ => Err(new_errno_error(Errno::EACCES)), |
| 368 | }) |
| 369 | } |
| 370 | |
Victor Hsieh | f7fc3d3 | 2021-11-22 10:20:33 -0800 | [diff] [blame] | 371 | fn statfs(&self) -> BinderResult<FsStat> { |
| 372 | let st = statvfs("/data").map_err(new_errno_error)?; |
| 373 | try_into_fs_stat(st).map_err(|_e| new_errno_error(Errno::EINVAL)) |
| 374 | } |
| 375 | } |
| 376 | |
| 377 | fn try_into_fs_stat(st: Statvfs) -> Result<FsStat, std::num::TryFromIntError> { |
| 378 | Ok(FsStat { |
| 379 | blockSize: st.block_size().try_into()?, |
| 380 | fragmentSize: st.fragment_size().try_into()?, |
| 381 | blockNumbers: st.blocks().try_into()?, |
| 382 | blockAvailable: st.blocks_available().try_into()?, |
| 383 | inodesAvailable: st.files_available().try_into()?, |
| 384 | maxFilename: st.name_max().try_into()?, |
| 385 | }) |
Victor Hsieh | b0f5fc8 | 2021-10-15 17:24:19 -0700 | [diff] [blame] | 386 | } |
| 387 | |
| 388 | fn read_into_buf(file: &File, max_size: usize, offset: u64) -> io::Result<Vec<u8>> { |
| 389 | let remaining = file.metadata()?.len().saturating_sub(offset); |
| 390 | let buf_size = min(remaining, max_size as u64) as usize; |
| 391 | let mut buf = vec![0; buf_size]; |
| 392 | file.read_exact_at(&mut buf, offset)?; |
| 393 | Ok(buf) |
| 394 | } |
Victor Hsieh | be8b08d | 2021-10-29 16:31:24 -0700 | [diff] [blame] | 395 | |
| 396 | fn new_errno_error(errno: Errno) -> Status { |
| 397 | new_binder_service_specific_error(errno as i32, errno.desc()) |
| 398 | } |
Victor Hsieh | 559b927 | 2021-11-08 15:15:14 -0800 | [diff] [blame] | 399 | |
| 400 | fn open_readonly_at(dir_fd: RawFd, path: &Path) -> nix::Result<File> { |
| 401 | let new_fd = openat(dir_fd, path, OFlag::O_RDONLY, Mode::empty())?; |
| 402 | // SAFETY: new_fd is just created successfully and not owned. |
| 403 | let new_file = unsafe { File::from_raw_fd(new_fd) }; |
| 404 | Ok(new_file) |
| 405 | } |
Victor Hsieh | dd99b46 | 2021-12-02 17:36:15 -0800 | [diff] [blame] | 406 | |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 407 | fn validate_and_cast_offset(offset: i64) -> Result<u64, Status> { |
| 408 | offset.try_into().map_err(|_| new_errno_error(Errno::EINVAL)) |
| 409 | } |
| 410 | |
| 411 | fn validate_and_cast_size(size: i32) -> Result<usize, Status> { |
| 412 | if size > MAX_REQUESTING_DATA { |
| 413 | Err(new_errno_error(Errno::EFBIG)) |
| 414 | } else { |
| 415 | size.try_into().map_err(|_| new_errno_error(Errno::EINVAL)) |
| 416 | } |
| 417 | } |
| 418 | |
Victor Hsieh | dd99b46 | 2021-12-02 17:36:15 -0800 | [diff] [blame] | 419 | fn validate_basename(name: &str) -> BinderResult<()> { |
| 420 | if name.contains(MAIN_SEPARATOR) { |
| 421 | Err(new_errno_error(Errno::EINVAL)) |
| 422 | } else { |
| 423 | Ok(()) |
| 424 | } |
| 425 | } |
Victor Hsieh | f393a72 | 2021-12-08 13:04:27 -0800 | [diff] [blame^] | 426 | |
| 427 | fn validate_file_mode(mode: i32) -> BinderResult<Mode> { |
| 428 | let mode = Mode::from_bits(mode as mode_t).ok_or_else(|| new_errno_error(Errno::EINVAL))?; |
| 429 | if mode.intersects(FORBIDDEN_MODES) { |
| 430 | Err(new_errno_error(Errno::EPERM)) |
| 431 | } else { |
| 432 | Ok(mode) |
| 433 | } |
| 434 | } |