netutil: fix leading zeros

AdguardTeam · Feb 11, 2022 · 917a851 · 917a851
1 parent 52db891
commit 917a851
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Showing 4 changed files with 31 additions and 49 deletions.
diff --git a/netutil/netutil_test.go b/netutil/netutil_test.go
@@ -16,7 +16,7 @@ var (
 	testIPv6ZeroTail = net.IP{
 		0x12, 0x34, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x00,
-		0x10, 0x00, 0x00, 0x00,
+		0x00, 0x00, 0x00, 0x00,
 		0x00, 0x00, 0x00, 0x00,
 	}
 )
diff --git a/netutil/reversed.go b/netutil/reversed.go
@@ -233,10 +233,6 @@ func ipv4NetFromReversed(arpa string) (subnet *net.IPNet, err error) {
 		}
 	}
 
-	if octet64 == 0 {
-		return nil, ErrNotAReversedSubnet
-	}
-
 	return &net.IPNet{
 		IP:   ip,
 		Mask: net.CIDRMask(l*8, IPv4BitLen),
@@ -280,10 +276,6 @@ func ipv6NetFromReversed(arpa string) (subnet *net.IPNet, err error) {
 		l++
 	}
 
-	if b == 0 {
-		return nil, ErrNotAReversedSubnet
-	}
-
 	return &net.IPNet{
 		IP:   ip,
 		Mask: net.CIDRMask(l*4, IPv6BitLen),

diff --git a/netutil/reversed_example_test.go b/netutil/reversed_example_test.go
@@ -15,14 +15,8 @@ func ExampleIPFromReversedAddr() {
 
 	fmt.Println(ip)
 
-	// Output:
-	//
-	// 1.2.3.4
-}
-
-func ExampleIPFromReversedAddr_ipv6() {
 	a := `4.3.2.1.d.c.b.a.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa`
-	ip, err := netutil.IPFromReversedAddr(a)
+	ip, err = netutil.IPFromReversedAddr(a)
 	if err != nil {
 		panic(err)
 	}
@@ -31,6 +25,7 @@ func ExampleIPFromReversedAddr_ipv6() {
 
 	// Output:
 	//
+	// 1.2.3.4
 	// ::abcd:1234
 }
 
@@ -42,14 +37,8 @@ func ExampleIPToReversedAddr() {
 
 	fmt.Println(arpa)
 
-	// Output:
-	//
-	// 4.3.2.1.in-addr.arpa
-}
-
-func ExampleIPToReversedAddr_ipv6() {
 	ip := net.ParseIP("::abcd:1234")
-	arpa, err := netutil.IPToReversedAddr(ip)
+	arpa, err = netutil.IPToReversedAddr(ip)
 	if err != nil {
 		panic(err)
 	}
@@ -58,6 +47,7 @@ func ExampleIPToReversedAddr_ipv6() {
 
 	// Output:
 	//
+	// 4.3.2.1.in-addr.arpa
 	// 4.3.2.1.d.c.b.a.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa
 }
 
@@ -69,14 +59,14 @@ func ExampleSubnetFromReversedAddr() {
 
 	fmt.Println(subnet)
 
-	// Output:
-	//
-	// 10.0.0.0/8
-}
+	subnet, err = netutil.SubnetFromReversedAddr("0.10.in-addr.arpa")
+	if err != nil {
+		panic(err)
+	}
 
-func ExampleSubnetFromReversedAddr_ipv6() {
-	a := `3.2.1.d.c.b.a.ip6.arpa`
-	subnet, err := netutil.SubnetFromReversedAddr(a)
+	fmt.Println(subnet)
+
+	subnet, err = netutil.SubnetFromReversedAddr("3.2.1.d.c.b.a.ip6.arpa")
 	if err != nil {
 		panic(err)
 	}
@@ -85,10 +75,12 @@ func ExampleSubnetFromReversedAddr_ipv6() {
 
 	// Output:
 	//
+	// 10.0.0.0/8
+	// 10.0.0.0/16
 	// abcd:1230::/28
 }
 
-func ExampleSubnetFromReversedAddr_domain() {
+func ExampleSubnetFromReversedAddr_domain_only() {
 	a := `in-addr.arpa`
 	_, err := netutil.SubnetFromReversedAddr(a)
 

diff --git a/netutil/reversed_test.go b/netutil/reversed_test.go
@@ -298,6 +298,12 @@ func TestSubnetFromReversedAddr(t *testing.T) {
 		wantErrMsg: "",
 		in:         `0.0.0.` + ipv4NetRevGood,
 		name:       "good_ipv4_single_addr_leading_zero",
+	}, {
+		want:       newIPNet(testIPv4ZeroTail, 8*2),
+		wantErrAs:  nil,
+		wantErrMsg: "",
+		in:         "0." + ipv4NetRevGood,
+		name:       "good_ipv4_subnet_leading_zero",
 	}, {
 		want:       newIPNet(testIPv4ZeroTail, 8),
 		wantErrAs:  nil,
@@ -318,27 +324,20 @@ func TestSubnetFromReversedAddr(t *testing.T) {
 			`bad ipv4 address "1.0.z.127"`,
 		in:   ipv4Char,
 		name: "bad_ipv4_char",
-	}, {
-		want:      nil,
-		wantErrAs: new(errors.Error),
-		wantErrMsg: `bad arpa domain name "0.` + ipv4NetRevGood + `": ` +
-			`not a reversed ip network`,
-		in:   "0." + ipv4NetRevGood,
-		name: "bad_ipv4_leading_zero",
 	}, {
 		want:      nil,
 		wantErrAs: new(*strconv.NumError),
 		wantErrMsg: `bad arpa domain name "x.` + ipv4NetRevGood + `": ` +
 			`strconv.ParseUint: parsing "x": invalid syntax`,
 		in:   `x.` + ipv4NetRevGood,
-		name: "bad_ipv4_bad_char",
+		name: "bad_ipv4_subnet_char",
 	}, {
 		want:      nil,
 		wantErrAs: new(*netutil.AddrError),
 		wantErrMsg: `bad arpa domain name "05.` + ipv4NetRevGood + `": ` +
 			`bad domain name label "05": leading zero is forbidden at this position`,
 		in:   `05.` + ipv4NetRevGood,
-		name: "bad_ipv4_unexpected_zero",
+		name: "bad_ipv4_subnet_unexpected_zero",
 	}, {
 		want:      nil,
 		wantErrAs: new(*netutil.AddrError),
@@ -364,12 +363,18 @@ func TestSubnetFromReversedAddr(t *testing.T) {
 		wantErrMsg: "",
 		in:         ipv6RevGoodUp,
 		name:       "good_ipv6_single_addr_case",
+	}, {
+		want:       newIPNet(testIPv6ZeroTail, netutil.IPv6BitLen),
+		wantErrAs:  nil,
+		wantErrMsg: "",
+		in:         ipv6RevZeroes + "." + ipv6RevGoodSuffix,
+		name:       "good_ipv6_single_addr_leading_zeroes",
 	}, {
 		want:       newIPNet(testIPv6ZeroTail, 4*17),
 		wantErrAs:  nil,
 		wantErrMsg: "",
-		in:         ipv6NetRevGood,
-		name:       "good_ipv6_subnet",
+		in:         "0." + ipv6RevGoodSuffix,
+		name:       "good_ipv6_subnet_leading_zeroes",
 	}, {
 		want:      nil,
 		wantErrAs: new(*netutil.AddrError),
@@ -440,13 +445,6 @@ func TestSubnetFromReversedAddr(t *testing.T) {
 			`not a reversed ip network`,
 		in:   ipv6NetRevHex,
 		name: "bad_ipv6_hex",
-	}, {
-		want:      nil,
-		wantErrAs: new(*netutil.AddrError),
-		wantErrMsg: `bad arpa domain name "` + ipv6RevGoodSuffix + `": ` +
-			`not a reversed ip network`,
-		in:   ipv6RevGoodSuffix,
-		name: "bad_ipv6_leading_zeroes",
 	}, {
 		want:      nil,
 		wantErrAs: new(errors.Error),