v1.13: ipam: Fix invalid PodCIDR in CiliumNode in ENI/Azure/MultiPool mode #30137
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[ upstream commit a4c43f3 ] [ backporter's notes: Had to reimplement the changes because that code moved from node.go to ipsec.go, but otherwise it didn't change. ] IPSec relies on the "pod subnet" CIDRs for encryption in IPAM modes (e.g. ENI, Azure) which do not have a pod CIDR (aka. alloc CIDR). Therefore, we should not use the alloc CIDR in such modes. This commit moves the setup of routes based on the alloc CIDR into the conditions which are executed if we do are not in pod subnet based encryption. In addition, we add some temporary code to remove the old bogus route based for the local node in subnet encryption mode. Signed-off-by: Sebastian Wicki <sebastian@isovalent.com> Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
[ upstream commit 1568558 ] This commit fixes an issue where Cilium-Agent would announce its internal auto-generated IPv4/IPv6AllocRange by writing it into the local CiliumNode resource. Cilium-Agents IPv4/IPv6AllocRange is Cilium's internal representation of the local node's PodCIDR. The concept of a single allocation CIDR however is outdated, since in many IPAM modes (ENI, Azure, AlibabaCloud, MultiPool) there either is no PodCIDR to begin with (and pod IPs are allocated using a different scheme), or there are multiple PodCIDRs (in the case of MultiPool). Before this commit, cilium-agent used to copy its internal PodCIDR into the CiliumNode resource, but this behavior is only correct in Kubernetes IPAM mode. In Kubernetes IPAM mode, the IPv4/IPv6AllocRange is taken from the Kubernetes Node resource, and thus it makes sense to announce it to other cilium-agent instances via the CiliumNode resource. This field then is for example used by `auto-direct-node-routes` to install routes for direct routing mode. However, in all other IPAM modes that we have, copying the internal PodCIDR into the CiliumNode resource does not make sense: - In ClusterPool mode, the CiliumNode PodCIDR field is populated by cilium-operator. Therefore, we should not try to overwrite it ourselves. This behavior is unchanged by this commit. - In all other current IPAM modes, the CiliumNode PodCIDR field is not used. Instead we use fields specific to those IPAM modes (c.f. CiliumNode.Spec.IPAM). In those modes, the previous code therefore wrote a auto-generatead, but otherwise valid IPv4/IPv6AllocRange into the field. That auto-generated PodCIDR is not used for pod IP allocation in those modes, so it does not make sense to announce it either. The announced auto-generated PodCIDR is causing issues in IPAM MultiPool mode. With this commit, we will no longer install invalid routes for the auto-generated PodCIDR. This was mostly harmless (since the auto-generated PodCIDR rarely overlapped with the real ones), but still a potential cause for confusion and bugs. In addition, ENI-mode users have reported that they are confused by the this "fake" PodCIDR, which is understandable, since that PodCIDR is meaningless in ENI mode (#9409). Long term, we want to remove the concept of the IPv4/IPv6AllocCIDR completely (and remove the auto-generation code), but this is a first incremental step towards that goal. Fixes: #9409 Signed-off-by: Sebastian Wicki <sebastian@isovalent.com> Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
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Manual backport of #26663.