net: make server.address() return a string for family

This reverts commits 68fb0bf,
4ad342a,
and 3a26db9.

Fixes: nodejs#43014

doc/api/dgram.md

@@ -114,6 +114,9 @@ exist and calls such as `socket.address()` and `socket.setTTL()` will fail.
 <!-- YAML
 added: v0.1.99
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/43054
+    description: The `family` property now returns a string instead of a number.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41431
     description: The `family` property now returns a number instead of a string.
@@ -125,7 +128,7 @@ The event handler function is passed two arguments: `msg` and `rinfo`.
 * `msg` {Buffer} The message.
 * `rinfo` {Object} Remote address information.
   * `address` {string} The sender address.
-  * `family` {number} The address family (`4` for IPv4 or `6` for IPv6).
+  * `family` {string} The address family (`'IPv4'` or `'IPv6'`).
   * `port` {number} The sender port.
   * `size` {number} The message size.
 

doc/api/net.md

@@ -286,6 +286,9 @@ Emitted when the server has been bound after calling [`server.listen()`][].
 <!-- YAML
 added: v0.1.90
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/43054
+    description: The `family` property now returns a string instead of a number.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41431
     description: The `family` property now returns a number instead of a string.
@@ -296,7 +299,7 @@ changes:
 Returns the bound `address`, the address `family` name, and `port` of the server
 as reported by the operating system if listening on an IP socket
 (useful to find which port was assigned when getting an OS-assigned address):
-`{ port: 12346, family: 4, address: '127.0.0.1' }`.
+`{ port: 12346, family: 'IPv4', address: '127.0.0.1' }`.
 
 For a server listening on a pipe or Unix domain socket, the name is returned
 as a string.
@@ -743,6 +746,9 @@ See also: [`socket.setTimeout()`][].
 <!-- YAML
 added: v0.1.90
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/43054
+    description: The `family` property now returns a string instead of a number.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41431
     description: The `family` property now returns a number instead of a string.
@@ -752,7 +758,7 @@ changes:
 
 Returns the bound `address`, the address `family` name and `port` of the
 socket as reported by the operating system:
-`{ port: 12346, family: 4, address: '127.0.0.1' }`
+`{ port: 12346, family: 'IPv4', address: '127.0.0.1' }`
 
 ### `socket.bufferSize`
 

doc/api/os.md

@@ -225,6 +225,9 @@ always `[0, 0, 0]`.
 <!-- YAML
 added: v0.6.0
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/43054
+    description: The `family` property now returns a string instead of a number.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41431
     description: The `family` property now returns a number instead of a string.
@@ -242,12 +245,12 @@ The properties available on the assigned network address object include:
 
 * `address` {string} The assigned IPv4 or IPv6 address
 * `netmask` {string} The IPv4 or IPv6 network mask
-* `family` {number} Either `4` (for IPv4) or `6` (for IPv6)
+* `family` {string} Either `IPv4` or `IPv6`
 * `mac` {string} The MAC address of the network interface
 * `internal` {boolean} `true` if the network interface is a loopback or
   similar interface that is not remotely accessible; otherwise `false`
 * `scopeid` {number} The numeric IPv6 scope ID (only specified when `family`
-  is `6`)
+  is `IPv6`)
 * `cidr` {string} The assigned IPv4 or IPv6 address with the routing prefix
   in CIDR notation. If the `netmask` is invalid, this property is set
   to `null`.
@@ -260,15 +263,15 @@ The properties available on the assigned network address object include:
     {
       address: '127.0.0.1',
       netmask: '255.0.0.0',
-      family: 4,
+      family: 'IPv4',
       mac: '00:00:00:00:00:00',
       internal: true,
       cidr: '127.0.0.1/8'
     },
     {
       address: '::1',
       netmask: 'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff',
-      family: 6,
+      family: 'IPv6',
       mac: '00:00:00:00:00:00',
       scopeid: 0,
       internal: true,
@@ -279,15 +282,15 @@ The properties available on the assigned network address object include:
     {
       address: '192.168.1.108',
       netmask: '255.255.255.0',
-      family: 4,
+      family: 'IPv4',
       mac: '01:02:03:0a:0b:0c',
       internal: false,
       cidr: '192.168.1.108/24'
     },
     {
       address: 'fe80::a00:27ff:fe4e:66a1',
       netmask: 'ffff:ffff:ffff:ffff::',
-      family: 6,
+      family: 'IPv6',
       mac: '01:02:03:0a:0b:0c',
       scopeid: 1,
       internal: false,

doc/api/tls.md

@@ -956,6 +956,9 @@ tlsSocket.once('session', (session) => {
 <!-- YAML
 added: v0.11.4
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/43054
+    description: The `family` property now returns a string instead of a number.
   - version: v18.0.0
     pr-url: https://github.com/nodejs/node/pull/41431
     description: The `family` property now returns a number instead of a string.
@@ -965,7 +968,7 @@ changes:
 
 Returns the bound `address`, the address `family` name, and `port` of the
 underlying socket as reported by the operating system:
-`{ port: 12346, family: 4, address: '127.0.0.1' }`.
+`{ port: 12346, family: 'IPv4', address: '127.0.0.1' }`.
 
 ### `tlsSocket.authorizationError`
 

lib/net.js

@@ -799,9 +799,7 @@ protoGetter('remoteAddress', function remoteAddress() {
 });
 
 protoGetter('remoteFamily', function remoteFamily() {
-  const { family } = this._getpeername();
-
-  return family ? `IPv${family}` : family;
+  return this._getpeername().family;
 });
 
 protoGetter('remotePort', function remotePort() {

lib/os.js

@@ -216,7 +216,7 @@ function getCIDR(address, netmask, family) {
   let groupLength = 8;
   let hasZeros = false;
 
-  if (family === 6) {
+  if (family === 'IPv6') {
     split = ':';
     range = 16;
     groupLength = 16;
@@ -248,7 +248,7 @@ function getCIDR(address, netmask, family) {
  * @returns {Record<string, Array<{
  *  address: string,
  *  netmask: string,
- *  family: 4 | 6,
+ *  family: 'IPv4' | 'IPv6',
  *  mac: string,
  *  internal: boolean,
  *  scopeid: number,

src/env.h

@@ -301,6 +301,8 @@ class NoArrayBufferZeroFillScope {
   V(input_string, "input")                                                     \
   V(internal_binding_string, "internalBinding")                                \
   V(internal_string, "internal")                                               \
+  V(ipv4_string, "IPv4")                                                       \
+  V(ipv6_string, "IPv6")                                                       \
   V(isclosing_string, "isClosing")                                             \
   V(issuer_string, "issuer")                                                   \
   V(issuercert_string, "issuerCertificate")                                    \

src/node_os.cc

@@ -174,8 +174,7 @@ static void GetInterfaceAddresses(const FunctionCallbackInfo<Value>& args) {
   char ip[INET6_ADDRSTRLEN];
   char netmask[INET6_ADDRSTRLEN];
   std::array<char, 18> mac;
-  Local<String> name;
-  Local<Integer> family;
+  Local<String> name, family;
 
   int err = uv_interface_addresses(&interfaces, &count);
 
@@ -215,14 +214,14 @@ static void GetInterfaceAddresses(const FunctionCallbackInfo<Value>& args) {
     if (interfaces[i].address.address4.sin_family == AF_INET) {
       uv_ip4_name(&interfaces[i].address.address4, ip, sizeof(ip));
       uv_ip4_name(&interfaces[i].netmask.netmask4, netmask, sizeof(netmask));
-      family = Integer::New(env->isolate(), 4);
+      family = env->ipv4_string();
     } else if (interfaces[i].address.address4.sin_family == AF_INET6) {
       uv_ip6_name(&interfaces[i].address.address6, ip, sizeof(ip));
       uv_ip6_name(&interfaces[i].netmask.netmask6, netmask, sizeof(netmask));
-      family = Integer::New(env->isolate(), 6);
+      family = env->ipv6_string();
     } else {
       strncpy(ip, "<unknown sa family>", INET6_ADDRSTRLEN);
-      family = Integer::New(env->isolate(), 0);
+      family = env->unknown_string();
     }
 
     result.emplace_back(name);

src/tcp_wrap.cc

@@ -402,9 +402,7 @@ MaybeLocal<Object> AddressToJS(Environment* env,
     info->Set(env->context(),
               env->address_string(),
               OneByteString(env->isolate(), ip)).Check();
-    info->Set(env->context(),
-              env->family_string(),
-              Integer::New(env->isolate(), 6)).Check();
+    info->Set(env->context(), env->family_string(), env->ipv6_string()).Check();
     info->Set(env->context(),
               env->port_string(),
               Integer::New(env->isolate(), port)).Check();
@@ -417,9 +415,7 @@ MaybeLocal<Object> AddressToJS(Environment* env,
     info->Set(env->context(),
               env->address_string(),
               OneByteString(env->isolate(), ip)).Check();
-    info->Set(env->context(),
-              env->family_string(),
-              Integer::New(env->isolate(), 4)).Check();
+    info->Set(env->context(), env->family_string(), env->ipv4_string()).Check();
     info->Set(env->context(),
               env->port_string(),
               Integer::New(env->isolate(), port)).Check();

test/common/index.js

@@ -854,7 +854,7 @@ const common = {
     const re = isWindows ? /Loopback Pseudo-Interface/ : /lo/;
     return Object.keys(iFaces).some((name) => {
       return re.test(name) &&
-             iFaces[name].some(({ family }) => family === 6);
+             iFaces[name].some(({ family }) => family === 'IPv6');
     });
   },
 

test/common/udppair.js

@@ -16,7 +16,7 @@ class FakeUDPWrap extends EventEmitter {
     this._handle.onwrite =
       (wrap, buffers, addr) => this._write(wrap, buffers, addr);
     this._handle.getsockname = (obj) => {
-      Object.assign(obj, { address: '127.0.0.1', family: 4, port: 1337 });
+      Object.assign(obj, { address: '127.0.0.1', family: 'IPv4', port: 1337 });
       return 0;
     };
 
@@ -72,8 +72,8 @@ class FakeUDPWrap extends EventEmitter {
 
     let familyInt;
     switch (family) {
-      case 4: familyInt = 4; break;
-      case 6: familyInt = 6; break;
+      case 'IPv4': familyInt = 4; break;
+      case 'IPv6': familyInt = 6; break;
       default: throw new Error('bad family');
     }
 

test/es-module/test-http-imports.mjs

@@ -39,10 +39,10 @@ const internalInterfaces = Object.values(os.networkInterfaces()).flat().filter(
 );
 for (const iface of internalInterfaces) {
   testListeningOptions.push({
-    hostname: iface?.family === 6 ? `[${iface.address}]` : iface?.address,
+    hostname: iface?.family === 'IPv6' ? `[${iface?.address}]` : iface?.address,
     listenOptions: {
       host: iface?.address,
-      ipv6Only: iface?.family === 6
+      ipv6Only: iface?.family === 'IPv6'
     }
   });
 }

test/internet/test-dgram-broadcast-multi-process.js

@@ -47,7 +47,7 @@ get_bindAddress: for (const name in networkInterfaces) {
   const interfaces = networkInterfaces[name];
   for (let i = 0; i < interfaces.length; i++) {
     const localInterface = interfaces[i];
-    if (!localInterface.internal && localInterface.family === 4) {
+    if (!localInterface.internal && localInterface.family === 'IPv4') {
       bindAddress = localInterface.address;
       break get_bindAddress;
     }

test/internet/test-dgram-multicast-set-interface-lo.js

@@ -49,7 +49,7 @@ const TMPL = (tail) => `${NOW} - ${tail}`;
 const interfaceAddress = ((networkInterfaces) => {
   for (const name in networkInterfaces) {
     for (const localInterface of networkInterfaces[name]) {
-      if (!localInterface.internal && `IPv${localInterface.family}` === FAM) {
+      if (!localInterface.internal && localInterface.family === FAM) {
         let interfaceAddress = localInterface.address;
         // On Windows, IPv6 would need: `%${localInterface.scopeid}`
         if (FAM === 'IPv6')

test/internet/test-dgram-multicast-ssm-multi-process.js

@@ -28,7 +28,7 @@ get_sourceAddress: for (const name in networkInterfaces) {
   const interfaces = networkInterfaces[name];
   for (let i = 0; i < interfaces.length; i++) {
     const localInterface = interfaces[i];
-    if (!localInterface.internal && localInterface.family === 4) {
+    if (!localInterface.internal && localInterface.family === 'IPv4') {
       sourceAddress = localInterface.address;
       break get_sourceAddress;
     }

test/internet/test-dgram-multicast-ssmv6-multi-process.js

@@ -28,7 +28,7 @@ get_sourceAddress: for (const name in networkInterfaces) {
   const interfaces = networkInterfaces[name];
   for (let i = 0; i < interfaces.length; i++) {
     const localInterface = interfaces[i];
-    if (!localInterface.internal && localInterface.family === 6) {
+    if (!localInterface.internal && localInterface.family === 'IPv6') {
       sourceAddress = localInterface.address;
       break get_sourceAddress;
     }

test/parallel/test-dgram-address.js

@@ -35,7 +35,7 @@ const dgram = require('dgram');
     assert.strictEqual(typeof address.port, 'number');
     assert.ok(isFinite(address.port));
     assert.ok(address.port > 0);
-    assert.strictEqual(address.family, 4);
+    assert.strictEqual(address.family, 'IPv4');
     socket.close();
   }));
 
@@ -59,7 +59,7 @@ if (common.hasIPv6) {
     assert.strictEqual(typeof address.port, 'number');
     assert.ok(isFinite(address.port));
     assert.ok(address.port > 0);
-    assert.strictEqual(address.family, 6);
+    assert.strictEqual(address.family, 'IPv6');
     socket.close();
   }));
 

test/parallel/test-dgram-udp6-link-local-address.js

@@ -12,7 +12,7 @@ const { isWindows } = common;
 function linklocal() {
   for (const [ifname, entries] of Object.entries(os.networkInterfaces())) {
     for (const { address, family, scopeid } of entries) {
-      if (family === 6 && address.startsWith('fe80:')) {
+      if (family === 'IPv6' && address.startsWith('fe80:')) {
         return { address, ifname, scopeid };
       }
     }

test/parallel/test-net-listen-invalid-port.js

@@ -12,7 +12,7 @@ const invalidPort = -1 >>> 0;
 
 net.Server().listen(0, function() {
   const address = this.address();
-  const key = `${address.family}:${address.address}:0`;
+  const key = `${address.family.slice(-1)}:${address.address}:0`;
 
   assert.strictEqual(this._connectionKey, key);
   this.close();

test/parallel/test-net-socket-connect-without-cb.js

@@ -17,7 +17,7 @@ const server = net.createServer(common.mustCall(function(conn) {
   }));
 
   const address = server.address();
-  if (!common.hasIPv6 && address.family === 6) {
+  if (!common.hasIPv6 && address.family === 'IPv6') {
     // Necessary to pass CI running inside containers.
     client.connect(address.port);
   } else {

test/parallel/test-os.js

@@ -138,7 +138,7 @@ switch (platform) {
     const expected = [{
       address: '127.0.0.1',
       netmask: '255.0.0.0',
-      family: 4,
+      family: 'IPv4',
       mac: '00:00:00:00:00:00',
       internal: true,
       cidr: '127.0.0.1/8'
@@ -154,7 +154,7 @@ switch (platform) {
     const expected = [{
       address: '127.0.0.1',
       netmask: '255.0.0.0',
-      family: 4,
+      family: 'IPv4',
       mac: '00:00:00:00:00:00',
       internal: true,
       cidr: '127.0.0.1/8'

test/sequential/test-net-server-address.js

@@ -26,7 +26,7 @@ const net = require('net');
 
 // Test on IPv4 Server
 {
-  const family = 4;
+  const family = 'IPv4';
   const server = net.createServer();
 
   server.on('error', common.mustNotCall());
@@ -46,7 +46,7 @@ if (!common.hasIPv6) {
   return;
 }
 
-const family6 = 6;
+const family6 = 'IPv6';
 const anycast6 = '::';
 
 // Test on IPv6 Server

test/sequential/test-net-server-bind.js

@@ -24,7 +24,7 @@ const net = require('net');
     const address = server.address();
     assert.strictEqual(address.port, common.PORT);
 
-    if (address.family === 6)
+    if (address.family === 'IPv6')
       assert.strictEqual(server._connectionKey, `6::::${address.port}`);
     else
       assert.strictEqual(server._connectionKey, `4:0.0.0.0:${address.port}`);