istio

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// Copyright Istio 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 trustdomain
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import "strings"
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// stringMatch checks if a string is in a list, it supports four types of string matches:
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// 1. Exact match.
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// 2. Wild character match. "*" matches any string.
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// 3. Prefix match. For example, "book*" matches "bookstore", "bookshop", etc.
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// 4. Suffix match. For example, "*/review" matches "/bookstore/review", "/products/review", etc.
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// This is an extensive version of model.stringMatch(). The pattern can be in the string or the list.
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func stringMatch(a string, list []string) bool {
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	for _, s := range list {
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		if a == s || s == "*" || prefixMatch(a, s) || prefixMatch(s, a) || suffixMatch(a, s) || suffixMatch(s, a) {
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			return true
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		}
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	}
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	return false
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}
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// prefixMatch checks if pattern is a prefix match and if string a has the given prefix.
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func prefixMatch(a string, pattern string) bool {
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	if !strings.HasSuffix(pattern, "*") {
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		return false
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	}
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	pattern = strings.TrimSuffix(pattern, "*")
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	return strings.HasPrefix(a, pattern)
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}
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// suffixMatch checks if pattern is a suffix match and if string a has the given suffix.
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func suffixMatch(a string, pattern string) bool {
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	if !strings.HasPrefix(pattern, "*") {
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		return false
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	}
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	pattern = strings.TrimPrefix(pattern, "*")
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	return strings.HasSuffix(a, pattern)
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}
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// isKeyInList it's fine to use this naive implementation for searching in a very short list.
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func isKeyInList(key string, list []string) bool {
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	for _, l := range list {
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		if key == l {
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			return true
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		}
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	}
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	return false
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}
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