ACL engine & tests

pkg/acl/engine.go

@@ -1,5 +1,51 @@
 package acl
 
+import (
+	"bufio"
+	"net"
+	"os"
+	"strings"
+)
+
 type Engine struct {
-	Entries []Entry
+	DefaultAction Action
+	Entries       []Entry
+}
+
+func LoadFromFile(filename string) (*Engine, error) {
+	f, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	scanner := bufio.NewScanner(f)
+	entries := make([]Entry, 0, 1024)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if len(line) == 0 || strings.HasPrefix(line, "#") {
+			// Ignore empty lines & comments
+			continue
+		}
+		entry, err := ParseEntry(line)
+		if err != nil {
+			return nil, err
+		}
+		entries = append(entries, entry)
+	}
+	return &Engine{
+		DefaultAction: ActionProxy,
+		Entries:       entries,
+	}, nil
+}
+
+func (e *Engine) Lookup(domain string, ip net.IP) (Action, string) {
+	if len(domain) == 0 && ip == nil {
+		return e.DefaultAction, ""
+	}
+	for _, entry := range e.Entries {
+		if entry.Match(domain, ip) {
+			return entry.Action, entry.ActionArg
+		}
+	}
+	return e.DefaultAction, ""
 }