pkg/proxy: move get kernel version out of ipvs proxier

Signed-off-by: Daman Arora <aroradaman@gmail.com>

pkg/util/kernel/constants.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package kernel
+
+// IPLocalReservedPortsNamespacedKernelVersion is the kernel version in which net.ipv4.ip_local_reserved_ports was namespaced(netns).
+// (ref: https://github.com/torvalds/linux/commit/122ff243f5f104194750ecbc76d5946dd1eec934)
+const IPLocalReservedPortsNamespacedKernelVersion = "3.16"
+
+// IPVSConnReuseModeMinSupportedKernelVersion is the minium kernel version supporting net.ipv4.vs.conn_reuse_mode.
+// (ref: https://github.com/torvalds/linux/commit/d752c364571743d696c2a54a449ce77550c35ac5)
+const IPVSConnReuseModeMinSupportedKernelVersion = "4.1"
+
+// TCPKeepAliveTimeNamespacedKernelVersion is the kernel version in which net.ipv4.tcp_keepalive_time was namespaced(netns).
+// (ref: https://github.com/torvalds/linux/commit/13b287e8d1cad951634389f85b8c9b816bd3bb1e)
+const TCPKeepAliveTimeNamespacedKernelVersion = "4.5"
+
+// TCPKeepAliveIntervalNamespacedKernelVersion is the kernel version in which net.ipv4.tcp_keepalive_intvl was namespaced(netns).
+// (ref: https://github.com/torvalds/linux/commit/b840d15d39128d08ed4486085e5507d2617b9ae1)
+const TCPKeepAliveIntervalNamespacedKernelVersion = "4.5"
+
+// TCPKeepAliveProbesNamespacedKernelVersion is the kernel version in which net.ipv4.tcp_keepalive_probes was namespaced(netns).
+// (ref: https://github.com/torvalds/linux/commit/9bd6861bd4326e3afd3f14a9ec8a723771fb20bb)
+const TCPKeepAliveProbesNamespacedKernelVersion = "4.5"
+
+// TCPFinTimeoutNamespacedKernelVersion is the kernel version in which net.ipv4.tcp_fin_timeout was namespaced(netns).
+// (ref: https://github.com/torvalds/linux/commit/1e579caa18b96f9eb18f4f5416658cd15f37c062)
+const TCPFinTimeoutNamespacedKernelVersion = "4.6"
+
+// IPVSConnReuseModeFixedKernelVersion is the kernel version in which net.ipv4.vs.conn_reuse_mode was fixed.
+// (ref: https://github.com/torvalds/linux/commit/35dfb013149f74c2be1ff9c78f14e6a3cd1539d1)
+const IPVSConnReuseModeFixedKernelVersion = "5.9"