Working config & permissions

config.json

@@ -0,0 +1,4 @@
+{
+	"ListenAddress": "127.0.0.1:3128",
+	"ListenType": "tcp4"
+}

internal/conf/config.go

@@ -0,0 +1,7 @@
+package conf
+
+type Config struct {
+	ListenAddress string // Address to listen on, passed to net.Listen
+	ListenType    string // Type of network to listen on, passed to net.Listen. One of tcp, tcp4 and tcp6
+
+}

internal/http/server.go

@@ -10,6 +10,8 @@ import (
 	"net/http"
 	"strings"
 	"time"
+
+	"edgaru089.ink/go/regolith/internal/perm"
 )
 
 const (
@@ -22,6 +24,24 @@ var (
 )
 
 type Server struct {
+	Perm *perm.Perm
+}
+
+// checkPerm invokes perm.Match.
+// If s.perm is nil, then every request is Accept-ed.
+//
+// It also logs if the action is Deny.
+func (s *Server) checkPerm(src, dest string) (act perm.Action) {
+	if s.Perm == nil {
+		return perm.ActionAccept
+	}
+
+	src_host, _, _ := net.SplitHostPort(src)
+	act = s.Perm.Match(src_host, dest)
+	if act == perm.ActionDeny {
+		log.Printf("denied: [%s] -> [%s]", src, dest)
+	}
+	return
 }
 
 func (s *Server) Serve(listener net.Listener) (err error) {
@@ -120,6 +140,12 @@ func (s *Server) handle_connect(conn net.Conn, req *http.Request) {
 	}
 	req_addr := net.JoinHostPort(req.URL.Hostname(), port)
 
+	// check permission
+	if s.checkPerm(conn.RemoteAddr().String(), req_addr) != perm.ActionAccept {
+		_ = simple_respond(conn, req, http.StatusBadGateway)
+		return
+	}
+
 	// prep for error log on close
 	var close_err error
 	defer func() {
@@ -164,11 +190,22 @@ func (s *Server) handle_request(conn net.Conn, req *http.Request) (should_keepal
 	remove_hop_headers(req.Header)
 	remove_extra_host_port(req)
 
-	if req.URL.Scheme == "" || req.URL.Host == "" {
+	if req.URL.Scheme != "http" || req.URL.Host == "" {
 		_ = simple_respond(conn, req, http.StatusBadRequest)
 		return false
 	}
 
+	// Check permission
+	req_hostname := req.URL.Hostname()
+	req_port := req.URL.Port()
+	if req_port == "" {
+		req_port = "80"
+	}
+	if s.checkPerm(conn.RemoteAddr().String(), net.JoinHostPort(req_hostname, req_port)) != perm.ActionAccept {
+		_ = simple_respond(conn, req, http.StatusBadGateway)
+		return false
+	}
+
 	// Request & error log
 	var close_err error
 	defer func() {

internal/perm/config.go

@@ -27,6 +27,20 @@ func MostSevere(a, b Action) Action {
 	return min(a, b)
 }
 
+func (a Action) String() (name string) {
+	switch a {
+	case ActionDeny:
+		name = "deny"
+	case ActionIgnore:
+		name = "ignore"
+	case ActionAccept:
+		name = "accept"
+	default:
+		name = "<" + strconv.Itoa(int(a)) + ">"
+	}
+	return
+}
+
 // Marshal/Unmarshal for Action
 func (a *Action) UnmarshalText(text []byte) error {
 	switch strings.ToLower(string(text)) {
@@ -42,25 +56,14 @@ func (a *Action) UnmarshalText(text []byte) error {
 	return nil
 }
 func (a Action) MarshalText() ([]byte, error) {
-	var name string
-	switch a {
-	case ActionDeny:
-		name = "deny"
-	case ActionIgnore:
-		name = "ignore"
-	case ActionAccept:
-		name = "accept"
-	default:
-		name = "<" + strconv.Itoa(int(a)) + ">"
-	}
-	return []byte(name), nil
+	return []byte(a.String()), nil
 }
 
 // Config is a list of address and actions, for each source address.
 // It can just be Marshal/Unmarshaled into/from json.
 type Config struct {
 	DefaultAction Action // What we should do when no action is matched.
-	DefaultPort   []uint // Port numbers to add to address without port numbers already in them. Don't put too many entries in here.
+	DefaultPort   []int  // Port numbers to add to address without port numbers already in them. Don't put too many entries in here.
 
 	// Object which holds addresses and optionally ports, mapping to actions.
 	//

internal/perm/perm.go

@@ -1,6 +1,7 @@
 package perm
 
 import (
+	"log"
 	"net"
 	"strconv"
 	"strings"
@@ -50,9 +51,11 @@ func (p *Perm) Load(cs map[string]Config) {
 	load_per_source := func(c Config) (p_int int_perm) {
 		p_int.match = make(map[string]Action)
 		p_int.def = c.DefaultAction
+		log.Printf("default action %s", p_int.def)
 
 		// insert helper to use the most severe action existing
 		insert := func(addrport string, action Action) {
+			log.Printf("loading target %s, action %s", addrport, action)
 			existing_action, ok := p_int.match[addrport]
 			if ok {
 				p_int.match[addrport] = MostSevere(existing_action, action)
@@ -69,7 +72,7 @@ func (p *Perm) Load(cs map[string]Config) {
 			} else {
 				// so this is why def_port shouldn't be that big
 				// TODO change this to sth faster
-				for def_port := range c.DefaultPort {
+				for _, def_port := range c.DefaultPort {
 					insert(net.JoinHostPort(addr, strconv.Itoa(def_port)), act)
 				}
 			}
@@ -78,6 +81,7 @@ func (p *Perm) Load(cs map[string]Config) {
 	}
 
 	for src, c := range cs {
+		log.Printf("loading source %s", src)
 		if strings.EqualFold(src, "$global") {
 			p.global = load_per_source(c)
 		} else {

main.go

@@ -1,29 +1,84 @@
 package main
 
 import (
+	"encoding/json"
 	"fmt"
+	"log"
 	"net"
 	"os"
 	"os/signal"
+	"syscall"
 
+	"edgaru089.ink/go/regolith/internal/conf"
 	"edgaru089.ink/go/regolith/internal/http"
+	"edgaru089.ink/go/regolith/internal/perm"
 )
 
 func main() {
+	var s *http.Server
 
-	listener, err := net.Listen("tcp", ":3128")
+	{
+		perm_buf, err := os.ReadFile("perm.json")
+		if err != nil {
+			panic(err)
+		}
+		perm_json := make(map[string]perm.Config)
+		err = json.Unmarshal(perm_buf, &perm_json)
+		if err != nil {
+			panic(err)
+		}
+		s = &http.Server{
+			Perm: perm.New(perm_json),
+		}
+	}
+
+	var conf conf.Config
+	{
+		conf_buf, err := os.ReadFile("config.json")
+		if err != nil {
+			panic(err)
+		}
+		err = json.Unmarshal(conf_buf, &conf)
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	listener, err := net.Listen(conf.ListenType, conf.ListenAddress)
 	if err != nil {
 		panic(err)
 	}
+	log.Printf("listeneing on [%s], type %s", conf.ListenAddress, conf.ListenType)
 
 	sigint_chan := make(chan os.Signal, 1)
 	signal.Notify(sigint_chan, os.Interrupt)
 	go func() {
 		<-sigint_chan
+		log.Printf("SIGINT received, quitting")
 		listener.Close()
 	}()
 
-	s := &http.Server{}
+	sighup_chan := make(chan os.Signal, 1)
+	signal.Notify(sighup_chan, syscall.SIGHUP)
+	go func() {
+		for {
+			<-sighup_chan
+			log.Printf("SIGHUP received, reloading permissions")
+			perm_buf, err := os.ReadFile("perm.json")
+			if err != nil {
+				log.Printf("skipping reload: error opening perm.json: %e", err)
+				continue
+			}
+			perm_json := make(map[string]perm.Config)
+			err = json.Unmarshal(perm_buf, &perm_json)
+			if err != nil {
+				log.Printf("skipping reload: error unmarshaling perm.json: %e", err)
+				continue
+			}
+			s.Perm.Load(perm_json)
+		}
+	}()
+
 	err = s.Serve(listener)
 	if err != nil {
 		fmt.Println(err)

perm.json

@@ -0,0 +1,21 @@
+{
+	"$global": {
+		"DefaultAction": "deny",
+		"DefaultPort": [443],
+		"Match": {
+			"mirrors.tuna.tsinghua.edu.cn": "accept",
+			"mirrors6.tuna.tsinghua.edu.cn": "accept",
+
+			"incoming.telemetry.mozilla.org": "ignore"
+		}
+	},
+	"127.0.0.1": {
+		"DefaultAction": "deny",
+		"DefaultPort": [443],
+		"Match": {
+			"pkg.go.dev": "accept",
+			"go.dev": "accept"
+		}
+	}
+}
+