hive-priv: drop the descriptor-taking snapshot send and its fd-receiving loop
This commit is contained in:
parent
20d286f06a
commit
418b50980c
1 changed files with 39 additions and 750 deletions
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@ -39,11 +39,9 @@ mod shared;
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mod storage;
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mod userns;
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use std::os::fd::{AsRawFd as _, FromRawFd as _, OwnedFd, RawFd};
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use anyhow::{Context as _, Result, bail};
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use hive_priv_sock::{PRIV_SOCK, PrivEvent, PrivRequest, PrivResponse};
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use tokio::io::AsyncWriteExt;
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use tokio::io::{AsyncBufReadExt, AsyncWriteExt, BufReader};
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use tokio::net::unix::OwnedWriteHalf;
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use tokio::net::{UnixListener, UnixStream};
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@ -130,162 +128,11 @@ fn socket_listener() -> Result<UnixListener> {
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Ok(listener)
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}
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/// Ancillary-data buffer sized and aligned for one `SCM_RIGHTS` message.
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///
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/// `CMSG_SPACE` is not a `const fn`, so the size is a literal with room
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/// to spare (24 bytes are needed for a single descriptor on x86-64). The
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/// union member gives the `cmsghdr` alignment `CMSG_FIRSTHDR` requires —
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/// a bare `[u8; N]` is only byte-aligned and would be undefined behaviour
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/// to walk.
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#[repr(C)]
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union CmsgSpace {
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_align: libc::cmsghdr,
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bytes: [u8; 32],
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}
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/// One `recvmsg` into `buf`, returning the bytes read plus any file
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/// descriptors that rode along as `SCM_RIGHTS`.
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///
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/// Why not a plain read: ancillary data is attached to a *specific*
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/// `recvmsg` call, so a buffered line reader cannot surface it — it
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/// reads the bytes and silently drops the descriptor.
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///
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/// `MSG_CMSG_CLOEXEC` is not optional: without it a received descriptor
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/// is inherited by every `btrfs` / `nixos-container` child this helper
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/// later spawns.
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fn recv_with_fds(sock: RawFd, buf: &mut [u8]) -> std::io::Result<(usize, Vec<OwnedFd>)> {
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const FD_SIZE: usize = std::mem::size_of::<RawFd>();
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let mut iov = libc::iovec {
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iov_base: buf.as_mut_ptr().cast(),
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iov_len: buf.len(),
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};
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let mut cmsg = CmsgSpace { bytes: [0; 32] };
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// SAFETY: msghdr is a plain C struct with no invalid bit patterns;
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// every field we care about is set immediately below.
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let mut msg: libc::msghdr = unsafe { std::mem::zeroed() };
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msg.msg_iov = &raw mut iov;
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msg.msg_iovlen = 1;
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msg.msg_control = std::ptr::addr_of_mut!(cmsg.bytes).cast();
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msg.msg_controllen = 32;
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// SAFETY: `msg` points at a live iovec covering `buf` and a live,
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// correctly aligned control buffer of the length we just declared.
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let n = unsafe { libc::recvmsg(sock, &raw mut msg, libc::MSG_CMSG_CLOEXEC) };
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if n < 0 {
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return Err(std::io::Error::last_os_error());
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}
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// Take ownership of every descriptor the kernel attached, even ones
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// this protocol never expects: an `OwnedFd` we drop is closed, an
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// fd we fail to claim is leaked for the lifetime of the process.
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let mut fds = Vec::new();
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// SAFETY: `msg` was just filled in by a successful `recvmsg`.
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let mut cmsgp = unsafe { libc::CMSG_FIRSTHDR(&raw const msg) };
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while !cmsgp.is_null() {
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// SAFETY: CMSG_FIRSTHDR / CMSG_NXTHDR only ever return a pointer
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// to a complete header inside the control buffer.
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let hdr = unsafe { std::ptr::read_unaligned(cmsgp) };
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if hdr.cmsg_level == libc::SOL_SOCKET && hdr.cmsg_type == libc::SCM_RIGHTS {
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// SAFETY: same, and CMSG_LEN(0) is the header's own length.
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let payload = hdr.cmsg_len as usize - unsafe { libc::CMSG_LEN(0) } as usize;
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let count = payload / FD_SIZE;
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// SAFETY: CMSG_DATA points at `payload` bytes of descriptors.
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let data = unsafe { libc::CMSG_DATA(cmsgp) };
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for i in 0..count {
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// Copied out byte-wise rather than read through a
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// `*const RawFd`: the control buffer is only guaranteed
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// `cmsghdr`-aligned, so casting to a more strictly
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// aligned pointer would be unsound even where it happens
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// to work.
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let mut raw = [0u8; FD_SIZE];
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// SAFETY: i < count, so this reads inside the payload.
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unsafe {
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std::ptr::copy_nonoverlapping(data.add(i * FD_SIZE), raw.as_mut_ptr(), FD_SIZE);
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}
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// SAFETY: the kernel just created this descriptor for
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// us — we are its only owner.
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fds.push(unsafe { OwnedFd::from_raw_fd(RawFd::from_ne_bytes(raw)) });
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}
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}
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// SAFETY: `cmsgp` came from this same message.
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cmsgp = unsafe { libc::CMSG_NXTHDR(&raw const msg, cmsgp) };
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}
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// `n >= 0` was checked above, so the conversion cannot fail; going
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// through `try_from` keeps it a cast-free, lint-clean widening.
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let read = usize::try_from(n).unwrap_or_default();
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Ok((read, fds))
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}
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/// Reads newline-delimited requests off one connection, pairing each
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/// with the descriptor that arrived with it.
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///
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/// The pairing is deliberately trivial, because the protocol is:
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/// `hive-sock-client` connects per request, so a connection carries one
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/// line and at most one descriptor. The loop below still handles several
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/// sequential requests (the server always has), but it refuses to guess
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/// — a second descriptor arriving before its line is a protocol error,
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/// not something to queue and hope about.
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struct Requests<'a> {
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sock: &'a UnixStream,
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buf: Vec<u8>,
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fd: Option<OwnedFd>,
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}
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impl Requests<'_> {
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/// Next complete request line and its descriptor, or `None` at EOF.
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async fn next(&mut self) -> Result<Option<(String, Option<OwnedFd>)>> {
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loop {
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if let Some(nl) = self.buf.iter().position(|&b| b == b'\n') {
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let line: Vec<u8> = self.buf.drain(..=nl).take(nl).collect();
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let line = String::from_utf8(line).context("request line was not valid UTF-8")?;
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return Ok(Some((line, self.fd.take())));
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}
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let mut chunk = [0u8; 8192];
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let raw = self.sock.as_raw_fd();
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let (n, fds) = self
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.sock
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.async_io(tokio::io::Interest::READABLE, || {
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recv_with_fds(raw, &mut chunk)
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})
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.await
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.context("recvmsg on the priv socket")?;
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for fd in fds {
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if self.fd.replace(fd).is_some() {
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bail!("more than one file descriptor passed for a single request");
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}
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}
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if n == 0 {
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if !self.buf.is_empty() {
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bail!("connection closed mid-request ({} bytes)", self.buf.len());
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}
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return Ok(None);
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}
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self.buf.extend_from_slice(&chunk[..n]);
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}
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}
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}
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async fn handle(stream: UnixStream) {
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let (reader, mut writer) = stream.into_split();
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let mut requests = Requests {
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sock: reader.as_ref(),
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buf: Vec::new(),
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fd: None,
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};
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loop {
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let (line, fd) = match requests.next().await {
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Ok(Some(req)) => req,
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Ok(None) => break,
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Err(e) => {
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tracing::warn!(error = %format!("{e:#}"), "reading request failed");
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break;
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}
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};
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let resp = dispatch(&line, fd, &mut writer).await;
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let mut lines = BufReader::new(reader).lines();
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while let Ok(Some(line)) = lines.next_line().await {
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let resp = dispatch(&line, &mut writer).await;
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// Write the terminal PrivResponse as a PrivEvent::Done. Wire-identical
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// to a bare PrivResponse (untagged), so old hive-c0re callers that
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// deserialise directly to PrivResponse continue to work.
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@ -301,24 +148,8 @@ async fn handle(stream: UnixStream) {
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}
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}
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/// Reject a request whose descriptor and operation disagree, in either
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/// direction.
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///
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/// No guessing when the caller didn't say: an op that streams into a
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/// passed descriptor cannot invent one, and an op that takes none must
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/// not silently accept one. Returning the `Err` here drops the
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/// `OwnedFd`, which closes it.
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fn check_fd_agreement(req: &PrivRequest, fd: Option<&OwnedFd>) -> Result<()> {
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let wants_fd = matches!(req, PrivRequest::SendAgentSnapshotToFd { .. });
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match (wants_fd, fd.is_some()) {
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(true, false) => bail!("this operation requires a passed file descriptor, none arrived"),
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(false, true) => bail!("this operation does not take a passed file descriptor"),
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_ => Ok(()),
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}
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}
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async fn dispatch(line: &str, fd: Option<OwnedFd>, writer: &mut OwnedWriteHalf) -> PrivResponse {
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response_of(run(line, fd, writer).await)
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async fn dispatch(line: &str, writer: &mut OwnedWriteHalf) -> PrivResponse {
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response_of(run(line, writer).await)
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}
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/// The wire answer for one request's outcome: the handler's output on
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@ -340,40 +171,25 @@ fn response_of(outcome: Result<(String, String)>) -> PrivResponse {
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}
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}
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/// Parse one request line, check it agrees with the descriptor that
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/// arrived with it, and execute it.
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/// Parse one request line and execute it.
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///
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/// Split out of [`dispatch`] so the three failure modes collapse into one
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/// `Result` instead of three nested matches building the same struct.
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async fn run(
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line: &str,
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fd: Option<OwnedFd>,
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writer: &mut OwnedWriteHalf,
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) -> Result<(String, String)> {
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/// Split out of [`dispatch`] so the two failure modes collapse into one
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/// `Result` instead of nested matches building the same struct.
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async fn run(line: &str, writer: &mut OwnedWriteHalf) -> Result<(String, String)> {
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let req = serde_json::from_str::<PrivRequest>(line).context("parse request")?;
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check_fd_agreement(&req, fd.as_ref())?;
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exec(req, fd, writer).await
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exec(req, writer).await
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}
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/// Execute a validated `PrivRequest`. Returns `(stdout, stderr)` on success.
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/// For streaming ops (`CreateContainer`/`UpdateContainer` with `stream: true`)
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/// output lines are forwarded to `writer` as `PrivEvent::Line` messages and
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/// the returned strings are empty.
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///
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/// `fd` is the descriptor that arrived with this request, already checked
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/// against the operation by [`check_fd_agreement`]: `Some` exactly for
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/// the variants that stream into a caller-supplied descriptor, `None`
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/// for every other operation.
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// One match arm per priv op — a flat 1:1 dispatch table. Every arm either
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// delegates directly or validates then delegates; an op whose handling is
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// more than that gets its own named function instead, so the match's length
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// tracks the op count, not complexity.
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#[allow(clippy::too_many_lines)]
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async fn exec(
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req: PrivRequest,
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fd: Option<OwnedFd>,
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writer: &mut OwnedWriteHalf,
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) -> Result<(String, String)> {
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async fn exec(req: PrivRequest, writer: &mut OwnedWriteHalf) -> Result<(String, String)> {
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match req {
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PrivRequest::StartContainer { ref name } => container::start_container(name).await,
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@ -514,96 +330,20 @@ async fn exec(
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.await
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}
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PrivRequest::SendAgentSnapshotToFd {
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ref agent_name,
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ref snapshot_name,
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ref parent_snapshot_name,
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} => {
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storage::exec_send_agent_snapshot_to_fd(
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agent_name,
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snapshot_name,
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parent_snapshot_name.as_deref(),
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fd,
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)
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.await
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}
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PrivRequest::SyncAgentTmpfiles => {
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files::remove_legacy_tmpfiles()?;
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Ok((String::new(), String::new()))
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}
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}
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}
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#[cfg(test)]
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mod tests {
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use std::io::Write as _;
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use std::os::fd::{AsRawFd as _, OwnedFd, RawFd};
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use std::os::unix::fs::MetadataExt as _;
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use hive_priv_sock::{PrivEvent, PrivRequest, PrivResponse};
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use tokio::io::{AsyncReadExt as _, AsyncWriteExt as _};
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use tokio::net::UnixStream;
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use super::{
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Requests, check_fd_agreement, check_socket_activation, dispatch, handle, recv_with_fds,
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response_of,
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};
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/// A request that streams into a caller-supplied descriptor.
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fn fd_taking_request() -> PrivRequest {
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PrivRequest::SendAgentSnapshotToFd {
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agent_name: "atlas".to_owned(),
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snapshot_name: "hive-migrate".to_owned(),
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parent_snapshot_name: None,
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}
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}
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/// A real descriptor — `/dev/null` rather than a fake, so the drop
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/// that closes it on a rejection path is genuinely exercised.
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fn some_fd() -> OwnedFd {
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std::fs::File::open("/dev/null")
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.expect("open /dev/null")
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.into()
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}
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/// An op that streams into a passed descriptor cannot invent one:
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/// falling back to anything (a temp file, the response socket) would
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/// send an agent's state somewhere the caller never asked for.
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#[test]
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fn an_fd_taking_op_without_a_descriptor_is_rejected() {
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let err = check_fd_agreement(&fd_taking_request(), None)
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.expect_err("no descriptor arrived, so this must not proceed");
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let msg = format!("{err:#}");
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assert!(msg.contains("requires a passed file descriptor"), "{msg}");
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}
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/// The mirror case: a descriptor sent alongside an op that takes
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/// none is a protocol error, not something to ignore. Returning the
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/// error drops the `OwnedFd`, which closes it — the alternative
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/// leaks one descriptor per stray request in a long-lived root
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/// process.
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#[test]
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fn a_descriptor_sent_to_an_op_that_takes_none_is_rejected() {
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let fd = some_fd();
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let err = check_fd_agreement(&PrivRequest::DaemonReload, Some(&fd))
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.expect_err("an unexpected descriptor must not be silently ignored");
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let msg = format!("{err:#}");
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assert!(
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msg.contains("does not take a passed file descriptor"),
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"{msg}"
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);
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}
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/// Both agreeing combinations pass, so the check rejects mismatches
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/// rather than descriptors in general.
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#[test]
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fn agreeing_combinations_are_accepted() {
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let fd = some_fd();
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check_fd_agreement(&fd_taking_request(), Some(&fd))
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.expect("an fd-taking op with its descriptor is the normal case");
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check_fd_agreement(&PrivRequest::DaemonReload, None)
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.expect("every ordinary request arrives without a descriptor");
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}
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use super::{check_socket_activation, dispatch, handle, response_of};
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/// An older hive-c0re's `SyncAgentTmpfiles` still decodes, payload and
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/// all, so it gets the legacy cleanup rather than a parse error. Control:
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@ -619,57 +359,6 @@ mod tests {
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assert!(serde_json::from_str::<PrivRequest>(r#"{"op":"sync_agent_tmpfilez"}"#).is_err());
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}
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/// `sendmsg` `bytes` with every descriptor of `fds` attached as one
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/// `SCM_RIGHTS` message: the client side of what `recv_with_fds` reads.
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fn send_with_fds(sock: RawFd, bytes: &[u8], fds: &[RawFd]) {
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const FD_SIZE: usize = std::mem::size_of::<RawFd>();
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let payload = u32::try_from(FD_SIZE * fds.len()).unwrap();
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let mut ctrl = [0u64; 8];
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let mut iov = libc::iovec {
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iov_base: bytes.as_ptr().cast_mut().cast(),
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iov_len: bytes.len(),
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};
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// SAFETY: msghdr is a plain C struct with no invalid bit patterns.
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let mut msg: libc::msghdr = unsafe { std::mem::zeroed() };
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msg.msg_iov = &raw mut iov;
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msg.msg_iovlen = 1;
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// SAFETY: CMSG_SPACE is a pure size computation.
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msg.msg_controllen = unsafe { libc::CMSG_SPACE(payload) } as _;
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msg.msg_control = ctrl.as_mut_ptr().cast();
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// SAFETY: `ctrl` is aligned for `cmsghdr` and large enough for the
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// header and `fds.len()` descriptors.
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unsafe {
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let hdr = libc::CMSG_FIRSTHDR(&raw const msg);
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(*hdr).cmsg_level = libc::SOL_SOCKET;
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(*hdr).cmsg_type = libc::SCM_RIGHTS;
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(*hdr).cmsg_len = libc::CMSG_LEN(payload) as _;
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std::ptr::copy_nonoverlapping(
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fds.as_ptr().cast::<u8>(),
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libc::CMSG_DATA(hdr),
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payload as usize,
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);
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assert!(libc::sendmsg(sock, &raw const msg, 0) >= 0, "sendmsg");
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}
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}
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fn is_cloexec(fd: &OwnedFd) -> bool {
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// SAFETY: `fd` is an open descriptor.
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let flags = unsafe { libc::fcntl(fd.as_raw_fd(), libc::F_GETFD) };
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flags >= 0 && flags & libc::FD_CLOEXEC != 0
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}
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fn same_file(fd: &OwnedFd, other: &std::fs::File) -> bool {
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let ours = std::fs::File::from(fd.try_clone().unwrap())
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.metadata()
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.unwrap();
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let theirs = other.metadata().unwrap();
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(ours.dev(), ours.ino()) == (theirs.dev(), theirs.ino())
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}
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fn dev_null() -> std::fs::File {
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std::fs::File::open("/dev/null").expect("open /dev/null")
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}
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// ---- socket activation ----
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/// Only systemd's own handover starts the daemon: at least one fd, and
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@ -702,161 +391,7 @@ mod tests {
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}
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}
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// ---- recv_with_fds ----
|
||||
|
||||
/// Plain bytes come back with no descriptors, and a closed peer reads as
|
||||
/// zero bytes.
|
||||
#[test]
|
||||
fn recv_reads_plain_bytes_and_end_of_stream() {
|
||||
let (a, b) = std::os::unix::net::UnixStream::pair().unwrap();
|
||||
(&a).write_all(b"hello").unwrap();
|
||||
drop(a);
|
||||
let mut buf = [0u8; 16];
|
||||
let (n, fds) = recv_with_fds(b.as_raw_fd(), &mut buf).unwrap();
|
||||
assert_eq!((&buf[..n], fds.len()), (&b"hello"[..], 0));
|
||||
let (n, fds) = recv_with_fds(b.as_raw_fd(), &mut buf).unwrap();
|
||||
assert_eq!((n, fds.len()), (0, 0));
|
||||
}
|
||||
|
||||
/// A descriptor sent with the bytes arrives as the same open file, and
|
||||
/// close-on-exec: without that every `btrfs` child the helper spawns
|
||||
/// would inherit it.
|
||||
#[test]
|
||||
fn recv_returns_the_passed_descriptor_close_on_exec() {
|
||||
let (a, b) = std::os::unix::net::UnixStream::pair().unwrap();
|
||||
let file = dev_null();
|
||||
send_with_fds(a.as_raw_fd(), b"x", &[file.as_raw_fd()]);
|
||||
let mut buf = [0u8; 16];
|
||||
let (n, mut fds) = recv_with_fds(b.as_raw_fd(), &mut buf).unwrap();
|
||||
assert_eq!(n, 1);
|
||||
assert_eq!(fds.len(), 1);
|
||||
let fd = fds.pop().unwrap();
|
||||
assert!(is_cloexec(&fd), "a received descriptor must be CLOEXEC");
|
||||
assert!(same_file(&fd, &file));
|
||||
}
|
||||
|
||||
/// Every descriptor of the message is claimed, even though the protocol
|
||||
/// takes one: an unclaimed one would leak for the life of the process.
|
||||
#[test]
|
||||
fn recv_claims_every_descriptor_of_a_message() {
|
||||
let (a, b) = std::os::unix::net::UnixStream::pair().unwrap();
|
||||
let (f1, f2) = (dev_null(), dev_null());
|
||||
send_with_fds(a.as_raw_fd(), b"x", &[f1.as_raw_fd(), f2.as_raw_fd()]);
|
||||
let mut buf = [0u8; 16];
|
||||
let (_, fds) = recv_with_fds(b.as_raw_fd(), &mut buf).unwrap();
|
||||
assert_eq!(fds.len(), 2);
|
||||
assert!(fds.iter().all(is_cloexec));
|
||||
}
|
||||
|
||||
/// A read on a descriptor that is not a socket is the OS error, not a
|
||||
/// panic or an empty read.
|
||||
#[test]
|
||||
fn recv_on_a_bad_descriptor_is_an_error() {
|
||||
let mut buf = [0u8; 4];
|
||||
assert!(recv_with_fds(-1, &mut buf).is_err());
|
||||
}
|
||||
|
||||
// ---- Requests: line framing and descriptor pairing ----
|
||||
|
||||
fn requests(sock: &UnixStream) -> Requests<'_> {
|
||||
Requests {
|
||||
sock,
|
||||
buf: Vec::new(),
|
||||
fd: None,
|
||||
}
|
||||
}
|
||||
|
||||
/// Lines are split at the newline, several in one read come out in
|
||||
/// order, and end of stream is `None`.
|
||||
#[tokio::test]
|
||||
async fn requests_split_lines_in_order_and_end_at_eof() {
|
||||
let (mut client, server) = UnixStream::pair().unwrap();
|
||||
client.write_all(b"one\ntwo\n\nthree\n").await.unwrap();
|
||||
drop(client);
|
||||
let mut reqs = requests(&server);
|
||||
for want in ["one", "two", "", "three"] {
|
||||
let (line, fd) = reqs.next().await.unwrap().unwrap();
|
||||
assert_eq!(line, want);
|
||||
assert!(fd.is_none());
|
||||
}
|
||||
assert!(reqs.next().await.unwrap().is_none());
|
||||
}
|
||||
|
||||
/// A line that arrives in pieces is one request.
|
||||
#[tokio::test]
|
||||
async fn requests_join_a_line_split_across_reads() {
|
||||
let (mut client, server) = UnixStream::pair().unwrap();
|
||||
let writer = tokio::spawn(async move {
|
||||
client.write_all(b"{\"op\":\"daemon").await.unwrap();
|
||||
client.flush().await.unwrap();
|
||||
tokio::time::sleep(std::time::Duration::from_millis(50)).await;
|
||||
client.write_all(b"_reload\"}\n").await.unwrap();
|
||||
});
|
||||
let mut reqs = requests(&server);
|
||||
let (line, _) = reqs.next().await.unwrap().unwrap();
|
||||
assert_eq!(line, r#"{"op":"daemon_reload"}"#);
|
||||
writer.await.unwrap();
|
||||
}
|
||||
|
||||
/// A connection that closes before the newline is an error naming how
|
||||
/// much was cut off, never a request.
|
||||
#[tokio::test]
|
||||
async fn requests_refuse_a_line_cut_off_by_eof() {
|
||||
let (mut client, server) = UnixStream::pair().unwrap();
|
||||
client.write_all(b"{\"op\":").await.unwrap();
|
||||
drop(client);
|
||||
let err = requests(&server).next().await.unwrap_err();
|
||||
assert!(
|
||||
format!("{err:#}").contains("closed mid-request (6 bytes)"),
|
||||
"{err:#}"
|
||||
);
|
||||
}
|
||||
|
||||
/// A line that is not UTF-8 is refused outright.
|
||||
#[tokio::test]
|
||||
async fn requests_refuse_a_line_that_is_not_utf8() {
|
||||
let (mut client, server) = UnixStream::pair().unwrap();
|
||||
client.write_all(b"\xff\xfe\n").await.unwrap();
|
||||
let err = requests(&server).next().await.unwrap_err();
|
||||
assert!(format!("{err:#}").contains("not valid UTF-8"), "{err:#}");
|
||||
}
|
||||
|
||||
/// The descriptor that came with a line is handed out with that line
|
||||
/// and with no other.
|
||||
#[tokio::test]
|
||||
async fn requests_pair_a_descriptor_with_its_line_only() {
|
||||
let (client, server) = UnixStream::pair().unwrap();
|
||||
let file = dev_null();
|
||||
send_with_fds(client.as_raw_fd(), b"first\n", &[file.as_raw_fd()]);
|
||||
send_with_fds(client.as_raw_fd(), b"second\n", &[]);
|
||||
let mut reqs = requests(&server);
|
||||
let (line, fd) = reqs.next().await.unwrap().unwrap();
|
||||
assert_eq!(line, "first");
|
||||
assert!(same_file(
|
||||
&fd.expect("the descriptor rides with its line"),
|
||||
&file
|
||||
));
|
||||
let (line, fd) = reqs.next().await.unwrap().unwrap();
|
||||
assert_eq!(line, "second");
|
||||
assert!(fd.is_none(), "the descriptor must not carry over");
|
||||
}
|
||||
|
||||
/// A second descriptor before the first one's line is complete is a
|
||||
/// protocol error, not something to queue.
|
||||
#[tokio::test]
|
||||
async fn requests_refuse_a_second_descriptor_for_one_line() {
|
||||
let (client, server) = UnixStream::pair().unwrap();
|
||||
let file = dev_null();
|
||||
send_with_fds(client.as_raw_fd(), b"par", &[file.as_raw_fd()]);
|
||||
send_with_fds(client.as_raw_fd(), b"tial\n", &[file.as_raw_fd()]);
|
||||
let err = requests(&server).next().await.unwrap_err();
|
||||
assert!(
|
||||
format!("{err:#}").contains("more than one file descriptor"),
|
||||
"{err:#}"
|
||||
);
|
||||
}
|
||||
|
||||
// ---- dispatch: parsing, fd agreement, validation, error mapping ----
|
||||
// ---- dispatch: parsing, validation, error mapping ----
|
||||
|
||||
/// Success carries the handler's output and no error; failure carries the
|
||||
/// whole context chain and no output.
|
||||
|
|
@ -880,9 +415,9 @@ mod tests {
|
|||
}
|
||||
|
||||
/// The failed response for `line`, asserting nothing else came back.
|
||||
async fn refused(line: &str, fd: Option<OwnedFd>) -> String {
|
||||
async fn refused(line: &str) -> String {
|
||||
let (mut w, _keep) = sink();
|
||||
let resp = dispatch(line, fd, &mut w).await;
|
||||
let resp = dispatch(line, &mut w).await;
|
||||
assert!(!resp.ok, "{line} was accepted");
|
||||
assert!(resp.stdout.is_empty() && resp.stderr.is_empty(), "{line}");
|
||||
resp.error.expect("a failure carries its error")
|
||||
|
|
@ -904,35 +439,11 @@ mod tests {
|
|||
r#"{"op":"start_container","name":7}"#,
|
||||
r#"{"op":"control_infra_container","container":"Forge","action":"stop"}"#,
|
||||
] {
|
||||
let msg = refused(line, None).await;
|
||||
let msg = refused(line).await;
|
||||
assert!(msg.starts_with("parse request"), "{line}: {msg}");
|
||||
}
|
||||
}
|
||||
|
||||
/// A descriptor on an op that takes none, and a missing one on an op that
|
||||
/// needs it, are answered with the refusal before the op runs.
|
||||
#[tokio::test]
|
||||
async fn a_fd_sent_to_an_op_that_takes_none_is_refused_before_it_runs() {
|
||||
// The name is bad too: only the descriptor check can produce this
|
||||
// message, so the op's own validation was not reached.
|
||||
let msg = refused(
|
||||
r#"{"op":"set_agent_paused","agent_name":"../x","paused":true}"#,
|
||||
Some(dev_null().into()),
|
||||
)
|
||||
.await;
|
||||
assert!(
|
||||
msg.contains("does not take a passed file descriptor"),
|
||||
"{msg}"
|
||||
);
|
||||
|
||||
let msg = refused(
|
||||
r#"{"op":"send_agent_snapshot_to_fd","agent_name":"atlas","snapshot_name":"hive-x","parent_snapshot_name":null}"#,
|
||||
None,
|
||||
)
|
||||
.await;
|
||||
assert!(msg.contains("requires a passed file descriptor"), "{msg}");
|
||||
}
|
||||
|
||||
/// Every op that names an agent or container refuses a bad name from the
|
||||
/// request line itself, before any command runs or path is built. A
|
||||
/// control (a valid name on the same op) is in the lifecycle and storage
|
||||
|
|
@ -1016,20 +527,9 @@ mod tests {
|
|||
));
|
||||
|
||||
for (line, want) in &cases {
|
||||
let msg = refused(line, None).await;
|
||||
let msg = refused(line).await;
|
||||
assert!(msg.contains(want), "{line}: {msg}");
|
||||
}
|
||||
// The fd op validates before it looks for its descriptor.
|
||||
let msg = refused(
|
||||
&named(
|
||||
"send_agent_snapshot_to_fd",
|
||||
"agent_name",
|
||||
r#","snapshot_name":"hive-x","parent_snapshot_name":null"#,
|
||||
),
|
||||
Some(dev_null().into()),
|
||||
)
|
||||
.await;
|
||||
assert!(msg.contains("invalid name"), "{msg}");
|
||||
}
|
||||
|
||||
/// Snapshot labels and the export file name are validated from the wire
|
||||
|
|
@ -1043,7 +543,7 @@ mod tests {
|
|||
};
|
||||
for op in ["snapshot_agent_subvolume", "delete_agent_snapshot"] {
|
||||
for label in ["", "x", "../hive-x", "hive-../x", "hive-a/b", "hive-a.b"] {
|
||||
let msg = refused(&snap(op, label), None).await;
|
||||
let msg = refused(&snap(op, label)).await;
|
||||
assert!(msg.contains("invalid"), "{op} {label:?}: {msg}");
|
||||
}
|
||||
}
|
||||
|
|
@ -1060,19 +560,16 @@ mod tests {
|
|||
("hive-x", "null", ""),
|
||||
("hive-x", "null", "out.img"),
|
||||
] {
|
||||
let msg = refused(&export(label, parent, dest), None).await;
|
||||
let msg = refused(&export(label, parent, dest)).await;
|
||||
assert!(msg.contains("invalid"), "{label} {parent} {dest}: {msg}");
|
||||
}
|
||||
let fd_op = r#"{"op":"send_agent_snapshot_to_fd","agent_name":"atlas","snapshot_name":"hive-x","parent_snapshot_name":"../x"}"#;
|
||||
let msg = refused(fd_op, Some(dev_null().into())).await;
|
||||
assert!(msg.contains("invalid"), "{msg}");
|
||||
}
|
||||
|
||||
/// The error is the whole anyhow chain, so a caller sees the cause and
|
||||
/// the context in one string.
|
||||
#[tokio::test]
|
||||
async fn the_error_carries_the_whole_context_chain() {
|
||||
let msg = refused(r#"{"op":"start_container","name":7}"#, None).await;
|
||||
let msg = refused(r#"{"op":"start_container","name":7}"#).await;
|
||||
assert!(msg.starts_with("parse request: "), "{msg}");
|
||||
assert!(msg.contains("invalid type"), "{msg}");
|
||||
}
|
||||
|
|
@ -1117,39 +614,22 @@ mod tests {
|
|||
assert!(resps.iter().all(|r| !r.ok));
|
||||
}
|
||||
|
||||
/// A connection that dies mid-line or sends non-UTF-8 gets no response
|
||||
/// and nothing runs.
|
||||
/// A connection that sends non-UTF-8 or nothing gets no response and
|
||||
/// nothing runs. A line cut off by EOF is still one line: it fails to
|
||||
/// parse and is answered with the parse error, never executed.
|
||||
#[tokio::test]
|
||||
async fn a_broken_request_closes_the_connection_without_a_response() {
|
||||
assert!(serve(b"{\"op\":\"start_cont").await.is_empty());
|
||||
async fn a_broken_request_closes_the_connection_without_running_anything() {
|
||||
assert!(serve(b"\xff\xfe\n").await.is_empty());
|
||||
assert!(serve(b"").await.is_empty());
|
||||
}
|
||||
|
||||
/// The descriptor check holds end to end: a stray descriptor on a
|
||||
/// request that takes none is answered with the refusal.
|
||||
#[tokio::test]
|
||||
async fn a_stray_descriptor_is_refused_over_the_wire() {
|
||||
let (client, server) = UnixStream::pair().unwrap();
|
||||
let task = tokio::spawn(handle(server));
|
||||
let file = dev_null();
|
||||
send_with_fds(
|
||||
client.as_raw_fd(),
|
||||
b"{\"op\":\"set_agent_paused\",\"agent_name\":\"../x\",\"paused\":true}\n",
|
||||
&[file.as_raw_fd()],
|
||||
);
|
||||
let (mut rd, mut wr) = client.into_split();
|
||||
wr.shutdown().await.unwrap();
|
||||
let mut raw = String::new();
|
||||
rd.read_to_string(&mut raw).await.unwrap();
|
||||
task.await.unwrap();
|
||||
let resp: PrivResponse = serde_json::from_str(raw.trim()).unwrap();
|
||||
assert!(!resp.ok);
|
||||
let cut = serve(b"{\"op\":\"start_cont").await;
|
||||
assert_eq!(cut.len(), 1);
|
||||
assert!(!cut[0].ok);
|
||||
assert!(
|
||||
resp.error
|
||||
cut[0]
|
||||
.error
|
||||
.as_deref()
|
||||
.unwrap()
|
||||
.contains("does not take a passed file descriptor"),
|
||||
"{raw}"
|
||||
.starts_with("parse request")
|
||||
);
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue