This allows us to use:
(1.26)
- impl Trait
- autoderef in pattern matching
- fixed slice patterns
- inclusive ranges
(1.27)
- dyn Trait
- #[must_use] on functions
To prepare for edition change, dyn is added where applicable. Other
edition changes would require bumping the requirement even higher,
and so they are not applied for now.
- Add MIN_MTU constants to the IP version modules.
- Ensure that ICMPv4 error replies comply with the size requirements
specified in RFC 1812 § 4.3.2.3.
- Add tests for the following
- ICMP error responses are not sent in response to broadcast requests
- ARP requests are responded to and inserted into the cache
- ARP requests for someone else are not responded to, but the sender
is still inserted in the cache
- Add the ttl member to the IpRepr
- Add the ttl member along with setters and getters to the tcp and udp
socket types
- Add unit tests for the new set_ttl parameter
- Update usage of IpRepr to include the ttl value
These functions only skipped the header, but what they should have
done is cut the packet at its total length and skip the header.
Otherwise, if the buffer the IP packet is constructed from contains
padding, such as Ethernet packets, the payload would be too long.
The use of this type has several drawbacks:
* It does not allow distinguishing between different error
conditions. In fact, we wrongly conflated some of them
before this commit.
* It does not allow propagation via ? and requires manual use
of map_err, which is especially tiresome for downstream code.
* It prevents us from expanding the set of error conditions
even if right now we have only one.
* It prevents us from blanket using Result<T> everywhere
(a nitpick at most).
Instead, use Result<T, Error> everywhere, and differentiate error
conditions where applicable.
This is a form of an uninitialized read bug; although safe it caused
panics. In short, transmit buffers received from the network stack
should be considered uninitialized (in practice they will often
contain previously transmitted packets or parts thereof). Wrapping
them with the only method we had (e.g. Ipv4Packet) treated the buffer
as if it contained a valid incoming packet, which can easily fail
with Error::Truncated.
This commit splits every `fn new(buffer: T) -> Result<Self, Error>`
method on a `Packet` into three smaller ones:
* `fn check_len(&self) -> Result<(), Error>`, purely a validator;
* `fn new(T) -> Self`, purely a wrapper;
* `fn new_checked(T) -> Result<Self, Error>`, a validating wrapper.
This makes it easy to process ingress packets (using `new_checked`),
egress packets (using `new`), and, if needed, maintain the invariants
at any point during packet construction (using `check_len`).
Fixes#17.
Before this commit, IP payload length was calculated by subtracting
the IP header length from the total underlying buffer length, which
fails if the underlying buffer has padding, e.g. like Ethernet
does.
Dario Nieuwenhuis
whitequark
Astro
Dan Robertson
Andrew Cann
寧靜
whitequark
Dan Robertson
Egor Karavaev
Steffen Butzer