41 lines
1.2 KiB
Go
41 lines
1.2 KiB
Go
// Copyright 2016 CNI authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package utils
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import (
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"crypto/sha512"
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"fmt"
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)
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const (
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maxChainLength = 28
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chainPrefix = "CNI-"
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prefixLength = len(chainPrefix)
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)
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// Generates a chain name to be used with iptables.
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// Ensures that the generated chain name is exactly
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// maxChainLength chars in length
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func FormatChainName(name string, id string) string {
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chainBytes := sha512.Sum512([]byte(name + id))
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chain := fmt.Sprintf("%s%x", chainPrefix, chainBytes)
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return chain[:maxChainLength]
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}
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// FormatComment returns a comment used for easier
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// rule identification within iptables.
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func FormatComment(name string, id string) string {
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return fmt.Sprintf("name: %q id: %q", name, id)
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}
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