perf: add fast paths to KeyMatch2/3/4/5 for literals and "*"

util/builtin_operators.go

@@ -56,6 +56,25 @@ func mustCompileOrGet(key string) *regexp.Regexp {
 	return re
 }
 
+// keyMatchFastPath handles cheap cases shared by KeyMatch2/3/4/5 before the
+// string-transform + RegexMatch path. handled=true means matched is final.
+//
+//  1. key2 == "*" → true (bare wildcard / domain admin). Avoids depending on
+//     compiling "^*$", which historically panicked on some Go versions (#330).
+//  2. key2 is a pure literal → key1 == key2. Literal means QuoteMeta(key2) == key2
+//     and no matcher-specific chars in extraPatternChars (e.g. ":" for KeyMatch2's
+//     :param dialect). Equality is inside this gate so patterns or stray regexp
+//     metas (".", "+", …) still take the regex path and keep prior behavior.
+func keyMatchFastPath(key1, key2, extraPatternChars string) (matched bool, handled bool) {
+	if key2 == "*" {
+		return true, true
+	}
+	if regexp.QuoteMeta(key2) == key2 && !strings.ContainsAny(key2, extraPatternChars) {
+		return key1 == key2, true
+	}
+	return false, false
+}
+
 // validate the variadic parameter size and type as string.
 func validateVariadicArgs(expectedLen int, args ...interface{}) error {
 	if len(args) != expectedLen {
@@ -137,6 +156,14 @@ func KeyGetFunc(args ...interface{}) (interface{}, error) {
 // KeyMatch2 determines whether key1 matches the pattern of key2 (similar to RESTful path), key2 can contain a *.
 // For example, "/foo/bar" matches "/foo/*", "/resource1" matches "/:resource".
 func KeyMatch2(key1 string, key2 string) bool {
+	// Fast paths avoid string-transform + RegexMatch work that dominates
+	// BuildRoleLinks when DomainMatchingFunc is KeyMatch2 over mostly-concrete
+	// domains (see #1004). extraPatternChars ":" covers KeyMatch2's :param
+	// dialect (not escaped by QuoteMeta).
+	if matched, handled := keyMatchFastPath(key1, key2, ":"); handled {
+		return matched
+	}
+
 	key2 = strings.Replace(key2, "/*", "/.*", -1)
 
 	key2 = keyMatch2Re.ReplaceAllString(key2, "$1[^/]+$2")
@@ -194,6 +221,10 @@ func KeyGet2Func(args ...interface{}) (interface{}, error) {
 // KeyMatch3 determines whether key1 matches the pattern of key2 (similar to RESTful path), key2 can contain a *.
 // For example, "/foo/bar" matches "/foo/*", "/resource1" matches "/{resource}".
 func KeyMatch3(key1 string, key2 string) bool {
+	if matched, handled := keyMatchFastPath(key1, key2, ""); handled {
+		return matched
+	}
+
 	key2 = strings.Replace(key2, "/*", "/.*", -1)
 	key2 = keyMatch3Re.ReplaceAllString(key2, "$1[^/]+$2")
 
@@ -253,6 +284,10 @@ func KeyGet3Func(args ...interface{}) (interface{}, error) {
 // "/parent/123/child/456" does not match "/parent/{id}/child/{id}"
 // But KeyMatch3 will match both.
 func KeyMatch4(key1 string, key2 string) bool {
+	if matched, handled := keyMatchFastPath(key1, key2, ""); handled {
+		return matched
+	}
+
 	key2 = strings.Replace(key2, "/*", "/.*", -1)
 
 	tokens := []string{}
@@ -312,6 +347,10 @@ func KeyMatch5(key1 string, key2 string) bool {
 		key1 = key1[:i]
 	}
 
+	if matched, handled := keyMatchFastPath(key1, key2, ""); handled {
+		return matched
+	}
+
 	key2 = strings.Replace(key2, "/*", "/.*", -1)
 	key2 = keyMatch5Re.ReplaceAllString(key2, "$1[^/]+$2")
 

util/builtin_operators_b_test.go

@@ -0,0 +1,57 @@
+// Copyright 2026 The casbin Authors. All Rights Reserved.
+//
+// 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 util
+
+import (
+	"fmt"
+	"testing"
+)
+
+// BenchmarkKeyMatch2_LiteralDomains mimics DomainManager comparing many
+// concrete domains (plus a bare "*" admin wildcard) during BuildRoleLinks.
+func BenchmarkKeyMatch2_LiteralDomains(b *testing.B) {
+	const n = 1200
+	domains := make([]string, n)
+	for i := 0; i < n; i++ {
+		domains[i] = fmt.Sprintf("team/%d", i)
+	}
+	domains = append(domains, "*")
+
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		for _, d1 := range domains {
+			for _, d2 := range domains {
+				_ = KeyMatch2(d1, d2)
+			}
+		}
+	}
+}
+
+func BenchmarkKeyMatch2_RESTPatterns(b *testing.B) {
+	pairs := [][2]string{
+		{"/proxy/myid/res", "/proxy/:id/*"},
+		{"/alice/all", "/:id/all"},
+		{"/resource1", "/:resource"},
+		{"/foo/bar", "/foo/*"},
+	}
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		for _, p := range pairs {
+			_ = KeyMatch2(p[0], p[1])
+		}
+	}
+}

util/builtin_operators_test.go

@@ -114,6 +114,30 @@ func TestKeyMatch2(t *testing.T) {
 	testKeyMatch2(t, "/alice/all", "/:id", false)
 
 	testKeyMatch2(t, "/alice/all", "/:/all", false)
+
+	// Bare "*" is match-any (domain wildcard / #330 — avoid depending on "^*$").
+	testKeyMatch2(t, "team/1", "*", true)
+	testKeyMatch2(t, "", "*", true)
+	testKeyMatch2(t, "*", "*", true)
+	testKeyMatch2(t, "*", "team/1", false)
+	// Pure literals only match via equality.
+	testKeyMatch2(t, "team/1", "team/2", false)
+	testKeyMatch2(t, "team/1", "team/1", true)
+	// ":" is KeyMatch2 :param dialect (not a Go regexp meta). Must NOT take the
+	// literal equality fast path: "team:1" becomes "team[^/]+", so unequal
+	// suffixes still match. KeyMatch3 treats ":" as a literal (see TestKeyMatch3).
+	testKeyMatch2(t, "team:1", "team:1", true)
+	testKeyMatch2(t, "team:1", "team:2", true)
+	testKeyMatch2(t, "team:1", "other:1", false)
+	// RegexMatch does not QuoteMeta key2: non-matcher regexp metas like "." must
+	// still take the regex path (behavior-preserving vs pre-fast-path KeyMatch2).
+	testKeyMatch2(t, "acmeXcom", "acme.com", true)
+	testKeyMatch2(t, "api.example.com", "api.example.com", true)
+	testKeyMatch2(t, "api.example.com", "api.example.org", false)
+	// key1 == key2 must NOT short-circuit to true when key2 carries a regexp
+	// metacharacter that does not match itself: "^a+b$" does not match "a+b".
+	testKeyMatch2(t, "a+b", "a+b", false)
+	testKeyMatch2(t, "a?b", "a?b", false)
 }
 
 func testKeyGet2(t *testing.T, key1 string, key2 string, pathVar string, res string) {
@@ -194,6 +218,16 @@ func TestKeyMatch3(t *testing.T) {
 	testKeyMatch3(t, "/proxy/", "/proxy/{id}/*", false)
 
 	testKeyMatch3(t, "/myid/using/myresid", "/{id/using/{resId}", false)
+
+	testKeyMatch3(t, "team/1", "*", true)
+	testKeyMatch3(t, "team/1", "team/2", false)
+	testKeyMatch3(t, "team/1", "team/1", true)
+	// Unlike KeyMatch2, ":" is not a pattern char here — pure literal equality.
+	testKeyMatch3(t, "team:1", "team:1", true)
+	testKeyMatch3(t, "team:1", "team:2", false)
+	testKeyMatch3(t, "acmeXcom", "acme.com", true)
+	testKeyMatch3(t, "a+b", "a+b", false)
+	testKeyMatch3(t, "a?b", "a?b", false)
 }
 
 func testKeyGet3(t *testing.T, key1 string, key2 string, pathVar string, res string) {
@@ -270,6 +304,38 @@ func TestKeyMatch4(t *testing.T) {
 	testKeyMatch4(t, "/parent/123/child/456", "/parent/{id}/child/{id}/book/{id}", false)
 
 	testKeyMatch4(t, "/parent/123/child/123", "/parent/{i/d}/child/{i/d}", false)
+
+	testKeyMatch4(t, "team/1", "*", true)
+	testKeyMatch4(t, "team/1", "team/2", false)
+	testKeyMatch4(t, "team/1", "team/1", true)
+	testKeyMatch4(t, "acmeXcom", "acme.com", true)
+	testKeyMatch4(t, "a+b", "a+b", false)
+	testKeyMatch4(t, "a?b", "a?b", false)
+}
+
+func testKeyMatch5(t *testing.T, key1 string, key2 string, res bool) {
+	t.Helper()
+	myRes := KeyMatch5(key1, key2)
+	t.Logf("%s < %s: %t", key1, key2, myRes)
+
+	if myRes != res {
+		t.Errorf("%s < %s: %t, supposed to be %t", key1, key2, !res, res)
+	}
+}
+
+func TestKeyMatch5(t *testing.T) {
+	testKeyMatch5(t, "/foo/bar?status=1&type=2", "/foo/bar", true)
+	testKeyMatch5(t, "/foo/bar?status=1&type=2", "/foo/baz", false)
+	testKeyMatch5(t, "/parent/child1?status=1", "/parent/*", true)
+
+	testKeyMatch5(t, "team/1", "*", true)
+	testKeyMatch5(t, "/foo/bar?x=1", "*", true)
+	testKeyMatch5(t, "team/1", "team/2", false)
+	testKeyMatch5(t, "team/1", "team/1", true)
+	testKeyMatch5(t, "/foo/bar?x=1", "/foo/bar", true)
+	testKeyMatch5(t, "acmeXcom", "acme.com", true)
+	testKeyMatch5(t, "a+b", "a+b", false)
+	testKeyMatch5(t, "a?b", "a?b", false)
 }
 
 func testRegexMatch(t *testing.T, key1 string, key2 string, res bool) {