Let fd_server return errno as service specific error
In order to provide more transparency of error code for debugging, and
to avoid expanding the similar constants defined in the AIDL, let the
service return error as binder's service specific error.
Bug: 203251769
Test: AuthFsHostTest
Change-Id: I4116a2502f13895decdd5c3a5f2027eeb7748399
diff --git a/authfs/fd_server/src/aidl.rs b/authfs/fd_server/src/aidl.rs
index b235025..48547e7 100644
--- a/authfs/fd_server/src/aidl.rs
+++ b/authfs/fd_server/src/aidl.rs
@@ -16,6 +16,7 @@
use anyhow::Result;
use log::error;
+use nix::errno::Errno;
use std::cmp::min;
use std::collections::BTreeMap;
use std::convert::TryInto;
@@ -26,30 +27,22 @@
use crate::fsverity;
use authfs_aidl_interface::aidl::com::android::virt::fs::IVirtFdService::{
- BnVirtFdService, IVirtFdService, ERROR_FILE_TOO_LARGE, ERROR_IO, ERROR_UNKNOWN_FD,
- MAX_REQUESTING_DATA,
+ BnVirtFdService, IVirtFdService, MAX_REQUESTING_DATA,
};
use authfs_aidl_interface::binder::{
- BinderFeatures, ExceptionCode, Interface, Result as BinderResult, Status, StatusCode, Strong,
+ BinderFeatures, Interface, Result as BinderResult, Status, StatusCode, Strong,
};
-use binder_common::new_binder_exception;
+use binder_common::new_binder_service_specific_error;
fn validate_and_cast_offset(offset: i64) -> Result<u64, Status> {
- offset.try_into().map_err(|_| {
- new_binder_exception(ExceptionCode::ILLEGAL_ARGUMENT, format!("Invalid offset: {}", offset))
- })
+ offset.try_into().map_err(|_| new_errno_error(Errno::EINVAL))
}
fn validate_and_cast_size(size: i32) -> Result<usize, Status> {
if size > MAX_REQUESTING_DATA {
- Err(new_binder_exception(
- ExceptionCode::ILLEGAL_ARGUMENT,
- format!("Unexpectedly large size: {}", size),
- ))
+ Err(new_errno_error(Errno::EFBIG))
} else {
- size.try_into().map_err(|_| {
- new_binder_exception(ExceptionCode::ILLEGAL_ARGUMENT, format!("Invalid size: {}", size))
- })
+ size.try_into().map_err(|_| new_errno_error(Errno::EINVAL))
}
}
@@ -89,7 +82,7 @@
where
F: FnOnce(&FdConfig) -> BinderResult<R>,
{
- let fd_config = self.fd_pool.get(&id).ok_or_else(|| Status::from(ERROR_UNKNOWN_FD))?;
+ let fd_config = self.fd_pool.get(&id).ok_or_else(|| new_errno_error(Errno::EBADF))?;
handler(fd_config)
}
}
@@ -105,7 +98,7 @@
FdConfig::Readonly { file, .. } | FdConfig::ReadWrite(file) => {
read_into_buf(file, size, offset).map_err(|e| {
error!("readFile: read error: {}", e);
- Status::from(ERROR_IO)
+ new_errno_error(Errno::EIO)
})
}
})
@@ -120,14 +113,14 @@
if let Some(tree_file) = &alt_merkle_tree {
read_into_buf(tree_file, size, offset).map_err(|e| {
error!("readFsverityMerkleTree: read error: {}", e);
- Status::from(ERROR_IO)
+ new_errno_error(Errno::EIO)
})
} else {
let mut buf = vec![0; size];
let s = fsverity::read_merkle_tree(file.as_raw_fd(), offset, &mut buf)
.map_err(|e| {
error!("readFsverityMerkleTree: failed to retrieve merkle tree: {}", e);
- Status::from(e.raw_os_error().unwrap_or(ERROR_IO))
+ new_errno_error(Errno::EIO)
})?;
debug_assert!(s <= buf.len(), "Shouldn't return more bytes than asked");
buf.truncate(s);
@@ -138,7 +131,7 @@
// For a writable file, Merkle tree is not expected to be served since Auth FS
// doesn't trust it anyway. Auth FS may keep the Merkle tree privately for its own
// use.
- Err(new_binder_exception(ExceptionCode::UNSUPPORTED_OPERATION, "Unsupported"))
+ Err(new_errno_error(Errno::ENOSYS))
}
})
}
@@ -152,13 +145,13 @@
let offset = 0;
read_into_buf(sig_file, size, offset).map_err(|e| {
error!("readFsveritySignature: read error: {}", e);
- Status::from(ERROR_IO)
+ new_errno_error(Errno::EIO)
})
} else {
let mut buf = vec![0; MAX_REQUESTING_DATA as usize];
let s = fsverity::read_signature(file.as_raw_fd(), &mut buf).map_err(|e| {
error!("readFsverityMerkleTree: failed to retrieve merkle tree: {}", e);
- Status::from(e.raw_os_error().unwrap_or(ERROR_IO))
+ new_errno_error(Errno::EIO)
})?;
debug_assert!(s <= buf.len(), "Shouldn't return more bytes than asked");
buf.truncate(s);
@@ -167,7 +160,7 @@
}
FdConfig::ReadWrite(_file) => {
// There is no signature for a writable file.
- Err(new_binder_exception(ExceptionCode::UNSUPPORTED_OPERATION, "Unsupported"))
+ Err(new_errno_error(Errno::ENOSYS))
}
})
}
@@ -176,19 +169,14 @@
self.handle_fd(id, |config| match config {
FdConfig::Readonly { .. } => Err(StatusCode::INVALID_OPERATION.into()),
FdConfig::ReadWrite(file) => {
- let offset: u64 = offset.try_into().map_err(|_| {
- new_binder_exception(ExceptionCode::ILLEGAL_ARGUMENT, "Invalid offset")
- })?;
+ let offset: u64 = offset.try_into().map_err(|_| new_errno_error(Errno::EINVAL))?;
// Check buffer size just to make `as i32` safe below.
if buf.len() > i32::MAX as usize {
- return Err(new_binder_exception(
- ExceptionCode::ILLEGAL_ARGUMENT,
- "Buffer size is too big",
- ));
+ return Err(new_errno_error(Errno::EOVERFLOW));
}
Ok(file.write_at(buf, offset).map_err(|e| {
error!("writeFile: write error: {}", e);
- Status::from(ERROR_IO)
+ new_errno_error(Errno::EIO)
})? as i32)
}
})
@@ -199,14 +187,11 @@
FdConfig::Readonly { .. } => Err(StatusCode::INVALID_OPERATION.into()),
FdConfig::ReadWrite(file) => {
if size < 0 {
- return Err(new_binder_exception(
- ExceptionCode::ILLEGAL_ARGUMENT,
- "Invalid size to resize to",
- ));
+ return Err(new_errno_error(Errno::EINVAL));
}
file.set_len(size as u64).map_err(|e| {
error!("resize: set_len error: {}", e);
- Status::from(ERROR_IO)
+ new_errno_error(Errno::EIO)
})
}
})
@@ -219,19 +204,19 @@
.metadata()
.map_err(|e| {
error!("getFileSize error: {}", e);
- Status::from(ERROR_IO)
+ new_errno_error(Errno::EIO)
})?
.len();
Ok(size.try_into().map_err(|e| {
error!("getFileSize: File too large: {}", e);
- Status::from(ERROR_FILE_TOO_LARGE)
+ new_errno_error(Errno::EFBIG)
})?)
}
FdConfig::ReadWrite(_file) => {
// Content and metadata of a writable file needs to be tracked by authfs, since
// fd_server isn't considered trusted. So there is no point to support getFileSize
// for a writable file.
- Err(new_binder_exception(ExceptionCode::UNSUPPORTED_OPERATION, "Unsupported"))
+ Err(new_errno_error(Errno::ENOSYS))
}
})
}
@@ -244,3 +229,7 @@
file.read_exact_at(&mut buf, offset)?;
Ok(buf)
}
+
+fn new_errno_error(errno: Errno) -> Status {
+ new_binder_service_specific_error(errno as i32, errno.desc())
+}