When reading a value into an enum from getsockopt, we must validate it.
Failing to do so can lead to UB for example with SOCK_PACKET on Linux.
Perform the validation in GetSockOpt::get. Currently SockType is the
only type that requires validation.
Fixes#1819
New implementation performs no allocations after all the necessary
structures are created, removes potentially unsound code that
was used by the old version (see below) and adds a bit more
documentation about bugs in how timeout is actually handled
```
let timeout = if let Some(mut t) = timeout {
t.as_mut() as *mut libc::timespec
} else {
ptr::null_mut()
};
```
This is already an unsafe function, dealing with pointers directly
does not make it much more unsafe but simplifies lifetimes later on
and similar to a previous commit allows to alocate a single buffer
to store all the control messages
CMSG_FIRSTHDR/CMSG_NEXTHDR operate in terms of pointers contained
inside msghdr structure, vector capacity doesn't matter for them.
This would change external behavior of recvmsg/recvmmsg in a sense
that buffer passed to store controll messages won't have it's length
updated but intended way to receive control messages is with cmsgs
iterator on `RecvMsg` which would still work.
This change is required to allow using a single vector to store
control messages from multiple packets
Clippy is now smarter about detecting unnecessary casts and
useless conversions, which means we need to be more explicit
about when the conversions are needed for a subset of platforms.
Required changes found by repeatedly running the following command
against a list of the supported platforms.
`xargs -t -I {} sh -c "cargo clippy -Zbuild-std --target {} --all-targets -- -D warnings || exit 255"`
I removed the casts it complained about, and then restored them
with an `#[allow]` if a later target needed the cast.
1776: Add support for the IP_SENDSRCADDR control message r=rtzoeller a=matttpt
This control message is available on FreeBSD, NetBSD, and OpenBSD. When used with `sendmsg`, it sets the IPv4 source address. This adds support through a new `ControlMessage::Ipv4SendSrcAddr` variant that complements `ControlMessageOwned::Ipv4RecvDstAddr`.
A few notes:
* `IP_SENDSRCADDR` is actually just an alias for `IP_RECVDSTADDR` (though the code doesn't depend on this).
* On NetBSD, `IP_PKTINFO` can be used to accomplish the same thing and is already supported by nix. On FreeBSD and OpenBSD, though, `IP_SENDSRCADDR` is the only method I'm aware of.
* The accompanying test binds a UDP socket to all local interfaces (0.0.0.0). If this is not acceptable, please let me know; however, FreeBSD requires this to use `IP_SENDSRCADDR`.
I'll add a change-log entry once I see the PR number.
Thanks!
Co-authored-by: Matthew Ingwersen <matttpt@gmail.com>
This control message (actually just an alias for IP_RECVDSTADDR) sets
the IPv4 source address when used with sendmsg. It is available on
FreeBSD, NetBSD, OpenBSD, and DragonFlyBSD.
The major users of this function are functions like gethostname, which
will always properly align their buffers. But out-of-crate consumers
could manually construct an unaligned buffer. Handle that correctly.
Enable Clippy's cast_ptr_alignment lint. It's disabled by default as it
reports many false positives, but it would've caught this problem.
Reported-by: Miri
Fixes: 1769
The SockAddr enum is quite large, and the user must allocate space for
the whole thing even though he usually knows what type he needs.
Furthermore, thanks to the sa_family field, the sockaddr types are
basically an enum even in C.
So replace the ungainly enum with a SockaddrLike trait implemented by
all sockaddr types and a SockaddrStorage union that has safe accessors.
Also, deprecate InetAddr, which only existed to support SockAddr.
Supplants #1504Fixes#1544
Link to cmsg_space macro for recvmmsg and recvmsg should
be the doc's root of crate as macro is an exported macro.
Signed-off-by: bin liu <liubin0329@gmail.com>
1618: Refactor UnixAddr r=asomers a=asomers
* Within UnixAddr, replace the path_len variable (length of the sun_path
field) with sun_len (length of the whole structure). This is more
similar to how other sockaddr types work, and it's the same way that the
BSDs use the sun_len field.
Also, don't require that sun_path be nul-terminated. The OS doesn't
require it.
* On BSD-derived operating systems, struct sockaddr has a sa_len field
that holds the length of the structure. UnixAddr's path_len field is
redundant. Remove path_len on BSD-derived OSes, retaining it only for
Illumos and Linux-based OSes.
Co-authored-by: Alan Somers <asomers@gmail.com>
Within UnixAddr, replace the path_len variable (length of the sun_path
field) with sun_len (length of the whole structure). This is more
similar to how other sockaddr types work, and it's the same way that the
BSDs use the sun_len field.
Also, don't require that sun_path be nul-terminated. The OS doesn't
require it.
1496: Rework UnixAddr to fix soundness issues r=asomers a=coolreader18
Fixes#1494
I went with making `sun_path` always nul-terminated since that just seems to make things easier, since (at least according to linux man pages) `sockaddr_un`s returned by the kernel will always be nul-terminated.
Co-authored-by: Noa <33094578+coolreader18@users.noreply.github.com>
Setting these options enables receiving errors, such as ICMP errors from
the network, via `recvmsg()` with `MSG_ERRQUEUE`.
Adds new `Ipv{4,6}RecvErr` variants to `ControlMessageOwned`. These
control messages are produced when `Ipv4RecvErr` or `Ipv6RecvErr`
options are enabled on a raw or datagram socket.
New tests for the functionality can be run with `cargo test --test test
test_recverr`.
This commit builds on an earlier draft of the functionality authored by
Matthew McPherrin <git@mcpherrin.ca>.
1473: sys/stat: add a safe wrapper for mknodat(2) r=asomers a=lucab
This introduces a new `mknodat` helper.
Ref: https://pubs.opengroup.org/onlinepubs/9699919799/functions/mknod.html
1474: Mark most C-derived enums as non_exhaustive r=asomers a=asomers
Since libc may add new variants at any time, Nix's consumers should not
use exhaustive match patterns.
Fixes#1182
1476: Constify many functions r=asomers a=asomers
Constify most functions that can be constified. The exceptions are
mostly accessors for structs that have no const constructor.
Co-authored-by: Luca BRUNO <luca.bruno@coreos.com>
Co-authored-by: Alan Somers <asomers@gmail.com>
