fold sysinfo into network

the backends are network backends

src/network.js

@@ -1,6 +1,9 @@
 'use strict';
 
 exports = module.exports = {
+    testIPv4Config,
+    testIPv6Config,
+
     getBlocklist,
     setBlocklist,
 
@@ -12,22 +15,55 @@ exports = module.exports = {
 
     getIPv6Config,
     setIPv6Config,
+
+    getIPv4,
+    hasIPv6,
+    getIPv6
 };
 
 const assert = require('assert'),
     BoxError = require('./boxerror.js'),
     cron = require('./cron.js'),
+    fs = require('fs'),
     ipaddr = require('ipaddr.js'),
     path = require('path'),
     paths = require('./paths.js'),
     safe = require('safetydance'),
     settings = require('./settings.js'),
     shell = require('./shell.js'),
-    sysinfo = require('./sysinfo.js'),
     validator = require('validator');
 
 const SET_BLOCKLIST_CMD = path.join(__dirname, 'scripts/setblocklist.sh');
 
+function api(provider) {
+    assert.strictEqual(typeof provider, 'string');
+
+    switch (provider) {
+    case 'noop': return require('./network/noop.js');
+    case 'fixed': return require('./network/fixed.js');
+    case 'network-interface': return require('./network/network-interface.js');
+    default: return require('./network/generic.js');
+    }
+}
+
+function hasIPv6() {
+    const IPV6_PROC_FILE = '/proc/net/if_inet6';
+    // on contabo, /proc/net/if_inet6 is an empty file. so just exists is not enough
+    return fs.existsSync(IPV6_PROC_FILE) && fs.readFileSync(IPV6_PROC_FILE, 'utf8').trim().length !== 0;
+}
+
+async function testIPv4Config(config) {
+    assert.strictEqual(typeof config, 'object');
+
+    return await api(config.provider).testIPv4Config(config);
+}
+
+async function testIPv6Config(config) {
+    assert.strictEqual(typeof config, 'object');
+
+    return await api(config.provider).testIPv6Config(config);
+}
+
 async function getBlocklist() {
     const value = await settings.getBlob(settings.FIREWALL_BLOCKLIST_KEY);
     return value ? value.toString('utf8') : '';
@@ -87,7 +123,7 @@ async function setIPv4Config(ipv4Config) {
 
     if (settings.isDemo()) throw new BoxError(BoxError.BAD_FIELD, 'Not allowed in demo mode');
 
-    const error = await sysinfo.testIPv4Config(ipv4Config);
+    const error = await testIPv4Config(ipv4Config);
     if (error) throw error;
 
     await settings.setJson(settings.IPV4_CONFIG_KEY, ipv4Config);
@@ -103,8 +139,22 @@ async function setIPv6Config(ipv6Config) {
 
     if (settings.isDemo()) throw new BoxError(BoxError.BAD_FIELD, 'Not allowed in demo mode');
 
-    const error = await sysinfo.testIPv6Config(ipv6Config);
+    const error = await testIPv6Config(ipv6Config);
     if (error) throw error;
 
     await settings.setJson(settings.IPV6_CONFIG_KEY, ipv6Config);
 }
+
+async function getIPv4() {
+    const config = await getIPv4Config();
+
+    return await api(config.provider).getIPv4(config);
+}
+
+// returns RFC 5952 formatted address (https://datatracker.ietf.org/doc/html/rfc5952)
+async function getIPv6() {
+    const config = await getIPv6Config();
+    const result = await api(config.provider).getIPv6(config);
+    if (!result) return null;
+    return ipaddr.parse(result).toRFC5952String();
+}