net_consomme: Add support for ipv6#2398
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This PR modifies files containing For more on why we check whole files, instead of just diffs, check out the Rustonomicon |
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Before this change goes in, I will update the validate_mana_nic function (in the vmm_tests) to ensure the device with a self-assigned IPv6 address. |
| let next_header = ipv6.next_header(); | ||
| let inner = &payload[smoltcp::wire::IPV6_HEADER_LEN..]; | ||
| let addresses = Ipv6Addresses { | ||
| src_addr: ipv6.src_addr(), | ||
| dst_addr: ipv6.dst_addr(), | ||
| }; | ||
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IPv6 packets can also be fragmented, but this implementation does not check for or reject fragmented IPv6 packets like it does for IPv4. IPv6 uses extension headers for fragmentation (Fragment Header, next header type 44). Without handling this, fragmented IPv6 packets will be processed as if they were complete, which could lead to incorrect behavior.
Consider adding a check for IPv6 fragmentation similar to the IPv4 check. You should verify that the next_header is not HopByHop (0), indicating extension headers might be present, and specifically check for the Fragment extension header (44). If fragmentation is detected, return DropReason::FragmentedPacket.
The following PRs: #2633 and #2398 require features that are only available in a newer version of smoltcp. Since the linked PRs are already large in size, it makes sense to do the version upgrade and corresponding build fixes in a separate PR. Unfortunately, there have been some changes in smoltcp that add bloat to our dependency list. Despite trying a myriad of combinations to turn off various features, I wasn't able to reduce the number of requisite dependencies that we have to pull in as a result of doing this upgrade.
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Looks good, just a few nits. |
This PR adds the ability for the net_consomme backend to process IPv6 traffic generated by a guest VM. Without this change, guest VM's would only reporting having an IPv4 address and a link-local IPv6 address assigned to the machine (see the image below). However, with the addition of a minimal DHCPv6 server and handling of the Neighbor Discovery Protocol (NDP) (an extension of ICMPv6 analogous to ARP for IPv4), guest VM's are able to generate their own global unicast IPv6 addresses with SLAAC (Stateless Address Autoconfiguration).
Before:
After:
Proper handling of TCP and UDP traffic over IPv6 was validated by spinning up a netcat server on a host machine that a guest VM would connect to by using the host machines global unicast IPv6 address.
Along with adding IPv6 support, this PR also introduces some changes to remove types that were defined in the net_consomme crate and replace them with types that already exist in various dependencies.
Addresses an item in the consomme backlog: #2313