feat: add more lenient address list parsing for MySQL lookup

addr.go

@@ -0,0 +1,32 @@
+package srsmilter
+
+import (
+	"net/mail"
+	"strings"
+	"unicode"
+)
+
+func split(email string) (string, Domain) {
+	at := strings.LastIndexByte(email, '@')
+	if at < 0 {
+		return email, ""
+	}
+	return email[:at], ToDomain(email[at+1:])
+}
+
+func parseAddressList(in string) (list []*mail.Address, err error) {
+	parts := strings.FieldsFunc(in, func(r rune) bool {
+		return r == ',' || unicode.IsSpace(r) || r == '\r' || r == '\n'
+	})
+	for _, p := range parts {
+		if len(p) == 0 {
+			continue
+		}
+		if a, err := mail.ParseAddress(p); err != nil {
+			return nil, err
+		} else {
+			list = append(list, a)
+		}
+	}
+	return list, nil
+}

addr_test.go

@@ -0,0 +1,59 @@
+package srsmilter
+
+import (
+	"net/mail"
+	"reflect"
+	"testing"
+)
+
+func Test_split(t *testing.T) {
+	tests := []struct {
+		name       string
+		email      string
+		wantLocal  string
+		wantDomain Domain
+	}{
+		{"empty", "", "", ""},
+		{"without domain", "root", "root", ""},
+		{"with domain", "root@localhost", "root", ToDomain("localhost")},
+		{"with two ats", "root@crazy@localhost", "root@crazy", ToDomain("localhost")},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotLocal, gotDomain := split(tt.email)
+			if gotLocal != tt.wantLocal {
+				t.Errorf("split() gotLocal = %v, want %v", gotLocal, tt.wantLocal)
+			}
+			if gotDomain != tt.wantDomain {
+				t.Errorf("split() gotDomain = %v, want %v", gotDomain, tt.wantDomain)
+			}
+		})
+	}
+}
+
+func Test_parseAddressList(t *testing.T) {
+	tests := []struct {
+		name     string
+		in       string
+		wantList []*mail.Address
+		wantErr  bool
+	}{
+		{"empty", "", nil, false},
+		{"one", "root@localhost", []*mail.Address{{Address: "root@localhost"}}, false},
+		{"padded", "  ,,,root@localhost\n,", []*mail.Address{{Address: "root@localhost"}}, false},
+		{"two", "  ,,,root@localhost\n,second@example.com\r\r\n", []*mail.Address{{Address: "root@localhost"}, {Address: "second@example.com"}}, false},
+		{"broken", "  ,,,root@localhost\n,second@example.com\rbroken\r\n", nil, true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotList, err := parseAddressList(tt.in)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("parseAddressList() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(gotList, tt.wantList) {
+				t.Errorf("parseAddressList() gotList = %v, want %v", gotList, tt.wantList)
+			}
+		})
+	}
+}

config.go

@@ -4,7 +4,6 @@ import (
 	"database/sql"
 	"fmt"
 	"net"
-	"net/mail"
 	"strings"
 
 	"github.com/d--j/go-milter/mailfilter/addr"
@@ -97,9 +96,9 @@ func (c *Configuration) ResolveForward(email *addr.RcptTo) (emails []*addr.RcptT
 			Log.Warn("scan error looking up forwards", "email", email.Addr, "err", err)
 			return []*addr.RcptTo{email}
 		}
-		addresses, err := mail.ParseAddressList(dest)
+		addresses, err := parseAddressList(dest)
 		if err != nil {
-			Log.Warn("parse error looking up forwards", "email", email.Addr, "err", err)
+			Log.Warn("parse error looking up forwards", "email", email.Addr, "dest", dest, "err", err)
 			return []*addr.RcptTo{email}
 		}
 		for _, a := range addresses {

socketmap.go

@@ -1,9 +1,5 @@
 package srsmilter
 
-import (
-	"strings"
-)
-
 func Socketmap(config *Configuration, lookup, key string) (result string, found bool, err error) {
 	logger := Log.New("sub", "socketmap", "lookup", lookup, "key", key)
 	if lookup != "decode" {
@@ -23,11 +19,3 @@ func Socketmap(config *Configuration, lookup, key string) (result string, found
 	logger.Debug("decoded", "result", email)
 	return email, true, nil
 }
-
-func split(email string) (string, Domain) {
-	at := strings.LastIndexByte(email, '@')
-	if at < 0 {
-		return email, ""
-	}
-	return email[:at], ToDomain(email[at+1:])
-}

socketmap_test.go

@@ -48,31 +48,3 @@ func TestSocketmap(t *testing.T) {
 		})
 	}
 }
-
-func Test_split(t *testing.T) {
-	type args struct {
-		email string
-	}
-	tests := []struct {
-		name       string
-		email      string
-		wantLocal  string
-		wantDomain Domain
-	}{
-		{"empty", "", "", ""},
-		{"without domain", "root", "root", ""},
-		{"with domain", "root@localhost", "root", ToDomain("localhost")},
-		{"with two ats", "root@crazy@localhost", "root@crazy", ToDomain("localhost")},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			gotLocal, gotDomain := split(tt.email)
-			if gotLocal != tt.wantLocal {
-				t.Errorf("split() gotLocal = %v, want %v", gotLocal, tt.wantLocal)
-			}
-			if gotDomain != tt.wantDomain {
-				t.Errorf("split() gotDomain = %v, want %v", gotDomain, tt.wantDomain)
-			}
-		})
-	}
-}