Merge branch 'addmeto.cc' into 'main'

CC/BCC support

See merge request etke.cc/postmoogle!40

README.md

@@ -102,6 +102,7 @@ If you want to change them - check available options in the help message (`!pm h
 
 * **!pm nosender** - Get or set `nosender` of the room (`true` - hide email sender; `false` - show email sender)
 * **!pm norecipient** - Get or set `norecipient` of the room (`true` - hide recipient; `false` - show recipient)
+* **!pm nocc** - Get or set `nocc` of the room (`true` - hide CC; `false` - show CC)
 * **!pm nosubject** - Get or set `nosubject` of the room (`true` - hide email subject; `false` - show email subject)
 * **!pm nohtml** - Get or set `nohtml` of the room (`true` - ignore HTML in email; `false` - parse HTML in emails)
 * **!pm nothreads** - Get or set `nothreads` of the room (`true` - ignore email threads; `false` - convert email threads into matrix threads)

bot/command.go

@@ -10,6 +10,7 @@ import (
 	"maunium.net/go/mautrix/format"
 	"maunium.net/go/mautrix/id"
 
+	"gitlab.com/etke.cc/postmoogle/email"
 	"gitlab.com/etke.cc/postmoogle/utils"
 )
 
@@ -120,6 +121,15 @@ func (b *Bot) initCommands() commandList {
 			sanitizer: utils.SanitizeBoolString,
 			allowed:   b.allowOwner,
 		},
+		{
+			key: roomOptionNoCC,
+			description: fmt.Sprintf(
+				"Get or set `%s` of the room (`true` - hide CC; `false` - show CC)",
+				roomOptionNoCC,
+			),
+			sanitizer: utils.SanitizeBoolString,
+			allowed:   b.allowOwner,
+		},
 		{
 			key: roomOptionNoSubject,
 			description: fmt.Sprintf(
@@ -415,7 +425,7 @@ func (b *Bot) runSend(ctx context.Context) {
 	tos := strings.Split(to, ",")
 	// validate first
 	for _, to := range tos {
-		if !utils.AddressValid(to) {
+		if !email.AddressValid(to) {
 			b.Error(ctx, evt.RoomID, "email address is not valid")
 			return
 		}
@@ -426,10 +436,10 @@ func (b *Bot) runSend(ctx context.Context) {
 
 	domain := utils.SanitizeDomain(cfg.Domain())
 	from := mailbox + "@" + domain
-	ID := utils.MessageID(evt.ID, domain)
+	ID := email.MessageID(evt.ID, domain)
 	for _, to := range tos {
-		email := utils.NewEmail(ID, "", " "+ID, subject, from, to, body, htmlBody, nil)
+		eml := email.New(ID, "", " "+ID, subject, from, to, to, "", body, htmlBody, nil)
-		data := email.Compose(b.getBotSettings().DKIMPrivateKey())
+		data := eml.Compose(b.getBotSettings().DKIMPrivateKey())
 		if data == "" {
 			b.SendError(ctx, evt.RoomID, "email body is empty")
 			return
@@ -437,14 +447,14 @@ func (b *Bot) runSend(ctx context.Context) {
 		queued, err := b.Sendmail(evt.ID, from, to, data)
 		if queued {
 			b.log.Error("cannot send email: %v", err)
-			b.saveSentMetadata(ctx, queued, evt.ID, email, &cfg)
+			b.saveSentMetadata(ctx, queued, evt.ID, eml, &cfg)
 			continue
 		}
 		if err != nil {
 			b.Error(ctx, evt.RoomID, "cannot send email to %s: %v", to, err)
 			continue
 		}
-		b.saveSentMetadata(ctx, false, evt.ID, email, &cfg)
+		b.saveSentMetadata(ctx, false, evt.ID, eml, &cfg)
 	}
 	if len(tos) > 1 {
 		b.SendNotice(ctx, evt.RoomID, "All emails were sent.")

bot/email.go

@@ -9,6 +9,7 @@ import (
 	"maunium.net/go/mautrix/format"
 	"maunium.net/go/mautrix/id"
 
+	"gitlab.com/etke.cc/postmoogle/email"
 	"gitlab.com/etke.cc/postmoogle/utils"
 )
 
@@ -25,8 +26,10 @@ const (
 	eventReferencesKey = "cc.etke.postmoogle.references"
 	eventInReplyToKey  = "cc.etke.postmoogle.inReplyTo"
 	eventSubjectKey    = "cc.etke.postmoogle.subject"
+	eventRcptToKey     = "cc.etke.postmoogle.rcptTo"
 	eventFromKey       = "cc.etke.postmoogle.from"
 	eventToKey         = "cc.etke.postmoogle.to"
+	eventCcKey         = "cc.etke.postmoogle.cc"
 )
 
 // SetSendmail sets mail sending func to the bot
@@ -83,7 +86,7 @@ func (b *Bot) GetMapping(mailbox string) (id.RoomID, bool) {
 }
 
 // GetIFOptions returns incoming email filtering options (room settings)
-func (b *Bot) GetIFOptions(roomID id.RoomID) utils.IncomingFilteringOptions {
+func (b *Bot) GetIFOptions(roomID id.RoomID) email.IncomingFilteringOptions {
 	cfg, err := b.getRoomSettings(roomID)
 	if err != nil {
 		b.log.Error("cannot retrieve room settings: %v", err)
@@ -94,7 +97,7 @@ func (b *Bot) GetIFOptions(roomID id.RoomID) utils.IncomingFilteringOptions {
 }
 
 // IncomingEmail sends incoming email to matrix room
-func (b *Bot) IncomingEmail(ctx context.Context, email *utils.Email) error {
+func (b *Bot) IncomingEmail(ctx context.Context, email *email.Email) error {
 	roomID, ok := b.GetMapping(email.Mailbox(true))
 	if !ok {
 		return errors.New("room not found")
@@ -147,18 +150,11 @@ func (b *Bot) SendEmailReply(ctx context.Context) {
 		b.Error(ctx, evt.RoomID, "mailbox is not configured, kupo")
 		return
 	}
-	domain := utils.SanitizeDomain(cfg.Domain())
 
 	b.lock(evt.RoomID.String())
 	defer b.unlock(evt.RoomID.String())
 
-	fromMailbox := mailbox + "@" + domain
+	meta := b.getParentEmail(evt, mailbox)
-	meta := b.getParentEmail(evt, domain)
-	// when email was sent from matrix and reply was sent from matrix again
-	if fromMailbox != meta.From {
-		meta.To = meta.From
-	}
-	meta.From = fromMailbox
 
 	if meta.To == "" {
 		b.Error(ctx, evt.RoomID, "cannot find parent email and continue the thread. Please, start a new email thread")
@@ -175,11 +171,11 @@ func (b *Bot) SendEmailReply(ctx context.Context) {
 	body := content.Body
 	htmlBody := content.FormattedBody
 
-	meta.MessageID = utils.MessageID(evt.ID, domain)
+	meta.MessageID = email.MessageID(evt.ID, meta.FromDomain)
 	meta.References = meta.References + " " + meta.MessageID
 	b.log.Debug("send email reply: %+v", meta)
-	email := utils.NewEmail(meta.MessageID, meta.InReplyTo, meta.References, meta.Subject, meta.From, meta.To, body, htmlBody, nil)
+	eml := email.New(meta.MessageID, meta.InReplyTo, meta.References, meta.Subject, meta.From, meta.To, meta.RcptTo, meta.CC, body, htmlBody, nil)
-	data := email.Compose(b.getBotSettings().DKIMPrivateKey())
+	data := eml.Compose(b.getBotSettings().DKIMPrivateKey())
 	if data == "" {
 		b.SendError(ctx, evt.RoomID, "email body is empty")
 		return
@@ -188,7 +184,7 @@ func (b *Bot) SendEmailReply(ctx context.Context) {
 	queued, err := b.Sendmail(evt.ID, meta.From, meta.To, data)
 	if queued {
 		b.log.Error("cannot send email: %v", err)
-		b.saveSentMetadata(ctx, queued, meta.ThreadID, email, &cfg)
+		b.saveSentMetadata(ctx, queued, meta.ThreadID, eml, &cfg)
 		return
 	}
 
@@ -197,19 +193,71 @@ func (b *Bot) SendEmailReply(ctx context.Context) {
 		return
 	}
 
-	b.saveSentMetadata(ctx, queued, meta.ThreadID, email, &cfg)
+	b.saveSentMetadata(ctx, queued, meta.ThreadID, eml, &cfg)
 }
 
 type parentEmail struct {
 	MessageID  string
 	ThreadID   id.EventID
 	From       string
+	FromDomain string
 	To         string
+	RcptTo     string
+	CC         string
 	InReplyTo  string
 	References string
 	Subject    string
 }
 
+// fixtofrom attempts to "fix" or rather reverse the To, From and CC headers
+// of parent email by using parent email as metadata source for a new email
+// that will be sent from postmoogle.
+// To do so, we need to reverse From and To headers, but Cc should be adjusted as well,
+// thus that hacky workaround below:
+func (e *parentEmail) fixtofrom(newSenderMailbox string, domains []string) {
+	newSenders := make(map[string]string, len(domains))
+	for _, domain := range domains {
+		sender := newSenderMailbox + "@" + domain
+		newSenders[sender] = sender
+	}
+
+	// try to determine previous email of the room mailbox
+	// by matching RCPT TO, To and From fields
+	// why? Because of possible multi-domain setup and we won't leak information
+	var previousSender string
+	rcptToSender, ok := newSenders[e.RcptTo]
+	if ok {
+		previousSender = rcptToSender
+	}
+	toSender, ok := newSenders[e.To]
+	if ok {
+		previousSender = toSender
+	}
+	fromSender, ok := newSenders[e.From]
+	if ok {
+		previousSender = fromSender
+	}
+
+	// Message-Id should not leak information either
+	e.FromDomain = utils.SanitizeDomain(utils.Hostname(previousSender))
+
+	originalFrom := e.From
+	// reverse From if needed
+	if fromSender == "" {
+		e.From = previousSender
+	}
+	// reverse To if needed
+	if toSender != "" {
+		e.To = originalFrom
+	}
+	// replace previous recipient of the email which is sender now with the original From
+	for newSender := range newSenders {
+		if strings.Contains(e.CC, newSender) {
+			e.CC = strings.ReplaceAll(e.CC, newSender, originalFrom)
+		}
+	}
+}
+
 func (b *Bot) getParentEvent(evt *event.Event) (id.EventID, *event.Event) {
 	content := evt.Content.AsMessage()
 	threadID := utils.EventParent(evt.ID, content)
@@ -246,8 +294,8 @@ func (b *Bot) getParentEvent(evt *event.Event) (id.EventID, *event.Event) {
 	return threadID, decrypted
 }
 
-func (b *Bot) getParentEmail(evt *event.Event, domain string) parentEmail {
+func (b *Bot) getParentEmail(evt *event.Event, newFromMailbox string) *parentEmail {
-	var parent parentEmail
+	parent := &parentEmail{}
 	threadID, parentEvt := b.getParentEvent(evt)
 	parent.ThreadID = threadID
 	if parentEvt == nil {
@@ -257,11 +305,14 @@ func (b *Bot) getParentEmail(evt *event.Event, domain string) parentEmail {
 		return parent
 	}
 
-	parent.MessageID = utils.MessageID(parentEvt.ID, domain)
 	parent.From = utils.EventField[string](&parentEvt.Content, eventFromKey)
 	parent.To = utils.EventField[string](&parentEvt.Content, eventToKey)
+	parent.CC = utils.EventField[string](&parentEvt.Content, eventCcKey)
+	parent.RcptTo = utils.EventField[string](&parentEvt.Content, eventRcptToKey)
 	parent.InReplyTo = utils.EventField[string](&parentEvt.Content, eventMessageIDkey)
 	parent.References = utils.EventField[string](&parentEvt.Content, eventReferencesKey)
+	parent.fixtofrom(newFromMailbox, b.domains)
+	parent.MessageID = email.MessageID(parentEvt.ID, parent.FromDomain)
 	if parent.InReplyTo == "" {
 		parent.InReplyTo = parent.MessageID
 	}
@@ -281,14 +332,14 @@ func (b *Bot) getParentEmail(evt *event.Event, domain string) parentEmail {
 
 // saveSentMetadata used to save metadata from !pm sent and thread reply events to a separate notice message
 // because that metadata is needed to determine email thread relations
-func (b *Bot) saveSentMetadata(ctx context.Context, queued bool, threadID id.EventID, email *utils.Email, cfg *roomSettings) {
+func (b *Bot) saveSentMetadata(ctx context.Context, queued bool, threadID id.EventID, eml *email.Email, cfg *roomSettings) {
-	text := "Email has been sent to " + email.To
+	text := "Email has been sent to " + eml.RcptTo
 	if queued {
-		text = "Email to " + email.To + " has been queued"
+		text = "Email to " + eml.RcptTo + " has been queued"
 	}
 
 	evt := eventFromContext(ctx)
-	content := email.Content(threadID, cfg.ContentOptions())
+	content := eml.Content(threadID, cfg.ContentOptions())
 	notice := format.RenderMarkdown(text, true, true)
 	msgContent, ok := content.Parsed.(*event.MessageEventContent)
 	if !ok {
@@ -305,8 +356,8 @@ func (b *Bot) saveSentMetadata(ctx context.Context, queued bool, threadID id.Eve
 		return
 	}
 	domain := utils.SanitizeDomain(cfg.Domain())
-	b.setThreadID(evt.RoomID, utils.MessageID(evt.ID, domain), threadID)
+	b.setThreadID(evt.RoomID, email.MessageID(evt.ID, domain), threadID)
-	b.setThreadID(evt.RoomID, utils.MessageID(msgID, domain), threadID)
+	b.setThreadID(evt.RoomID, email.MessageID(msgID, domain), threadID)
 	b.setLastEventID(evt.RoomID, threadID, msgID)
 }
 

bot/settings_room.go

@@ -5,6 +5,7 @@ import (
 
 	"maunium.net/go/mautrix/id"
 
+	"gitlab.com/etke.cc/postmoogle/email"
 	"gitlab.com/etke.cc/postmoogle/utils"
 )
 
@@ -17,6 +18,7 @@ const (
 	roomOptionMailbox       = "mailbox"
 	roomOptionDomain        = "domain"
 	roomOptionNoSend        = "nosend"
+	roomOptionNoCC          = "nocc"
 	roomOptionNoSender      = "nosender"
 	roomOptionNoRecipient   = "norecipient"
 	roomOptionNoSubject     = "nosubject"
@@ -61,6 +63,10 @@ func (s roomSettings) NoSend() bool {
 	return utils.Bool(s.Get(roomOptionNoSend))
 }
 
+func (s roomSettings) NoCC() bool {
+	return utils.Bool(s.Get(roomOptionNoCC))
+}
+
 func (s roomSettings) NoSender() bool {
 	return utils.Bool(s.Get(roomOptionNoSender))
 }
@@ -143,8 +149,9 @@ func (s roomSettings) migrateSpamlistSettings() {
 }
 
 // ContentOptions converts room display settings to content options
-func (s roomSettings) ContentOptions() *utils.ContentOptions {
+func (s roomSettings) ContentOptions() *email.ContentOptions {
-	return &utils.ContentOptions{
+	return &email.ContentOptions{
+		CC:        !s.NoCC(),
 		HTML:      !s.NoHTML(),
 		Sender:    !s.NoSender(),
 		Recipient: !s.NoRecipient(),
@@ -152,7 +159,9 @@ func (s roomSettings) ContentOptions() *utils.ContentOptions {
 		Threads:   !s.NoThreads(),
 
 		ToKey:         eventToKey,
+		CcKey:         eventCcKey,
 		FromKey:       eventFromKey,
+		RcptToKey:     eventRcptToKey,
 		SubjectKey:    eventSubjectKey,
 		MessageIDKey:  eventMessageIDkey,
 		InReplyToKey:  eventInReplyToKey,

email/email.go

@@ -1,31 +1,20 @@
-package utils
+package email
 
 import (
 	"crypto"
 	"crypto/x509"
 	"encoding/pem"
-	"fmt"
-	"net/mail"
-	"regexp"
 	"strings"
-	"time"
 
 	"github.com/emersion/go-msgauth/dkim"
 	"github.com/jhillyerd/enmime"
 	"maunium.net/go/mautrix/event"
 	"maunium.net/go/mautrix/format"
 	"maunium.net/go/mautrix/id"
+
+	"gitlab.com/etke.cc/postmoogle/utils"
 )
 
-var styleRegex = regexp.MustCompile("<style((.|\n|\r)*?)<\\/style>")
-
-// IncomingFilteringOptions for incoming mail
-type IncomingFilteringOptions interface {
-	SpamcheckSMTP() bool
-	SpamcheckMX() bool
-	Spamlist() []string
-}
-
 // Email object
 type Email struct {
 	Date       string
@@ -34,50 +23,25 @@ type Email struct {
 	References string
 	From       string
 	To         string
+	RcptTo     string
+	CC         string
 	Subject    string
 	Text       string
 	HTML       string
-	Files      []*File
+	Files      []*utils.File
 }
 
-// ContentOptions represents settings that specify how an email is to be converted to a Matrix message
+// New constructs Email object
-type ContentOptions struct {
+func New(messageID, inReplyTo, references, subject, from, to, rcptto, cc, text, html string, files []*utils.File) *Email {
-	// On/Off
-	Sender    bool
-	Recipient bool
-	Subject   bool
-	HTML      bool
-	Threads   bool
-
-	// Keys
-	MessageIDKey  string
-	InReplyToKey  string
-	ReferencesKey string
-	SubjectKey    string
-	FromKey       string
-	ToKey         string
-}
-
-// AddressValid checks if email address is valid
-func AddressValid(email string) bool {
-	_, err := mail.ParseAddress(email)
-	return err == nil
-}
-
-// MessageID generates email Message-Id from matrix event ID
-func MessageID(eventID id.EventID, domain string) string {
-	return fmt.Sprintf("<%s@%s>", eventID, domain)
-}
-
-// NewEmail constructs Email object
-func NewEmail(messageID, inReplyTo, references, subject, from, to, text, html string, files []*File) *Email {
 	email := &Email{
-		Date:       time.Now().UTC().Format(time.RFC1123Z),
+		Date:       dateNow(),
 		MessageID:  messageID,
 		InReplyTo:  inReplyTo,
 		References: references,
 		From:       from,
 		To:         to,
+		CC:         cc,
+		RcptTo:     rcptto,
 		Subject:    subject,
 		Text:       text,
 		HTML:       html,
@@ -92,12 +56,46 @@ func NewEmail(messageID, inReplyTo, references, subject, from, to, text, html st
 	return email
 }
 
+// FromEnvelope constructs Email object from envelope
+func FromEnvelope(rcptto string, envelope *enmime.Envelope) *Email {
+	datetime, _ := envelope.Date() //nolint:errcheck // handled in dateNow()
+	date := dateNow(datetime)
+
+	var html string
+	if envelope.HTML != "" {
+		html = styleRegex.ReplaceAllString(envelope.HTML, "")
+	}
+
+	files := make([]*utils.File, 0, len(envelope.Attachments))
+	for _, attachment := range envelope.Attachments {
+		file := utils.NewFile(attachment.FileName, attachment.Content)
+		files = append(files, file)
+	}
+
+	email := &Email{
+		Date:       date,
+		MessageID:  envelope.GetHeader("Message-Id"),
+		InReplyTo:  envelope.GetHeader("In-Reply-To"),
+		References: envelope.GetHeader("References"),
+		From:       envelope.GetHeader("From"),
+		To:         envelope.GetHeader("To"),
+		RcptTo:     rcptto,
+		CC:         envelope.GetHeader("Cc"),
+		Subject:    envelope.GetHeader("Subject"),
+		Text:       envelope.Text,
+		HTML:       html,
+		Files:      files,
+	}
+
+	return email
+}
+
 // Mailbox returns postmoogle's mailbox, parsing it from FROM (if incoming=false) or TO (incoming=true)
 func (e *Email) Mailbox(incoming bool) string {
 	if incoming {
-		return Mailbox(e.To)
+		return utils.Mailbox(e.RcptTo)
 	}
-	return Mailbox(e.From)
+	return utils.Mailbox(e.From)
 }
 
 // Content converts the email object to a Matrix event content
@@ -110,7 +108,11 @@ func (e *Email) Content(threadID id.EventID, options *ContentOptions) *event.Con
 		text.WriteString(" ➡️ ")
 		text.WriteString(e.To)
 	}
-	if options.Sender || options.Recipient {
+	if options.CC && e.CC != "" {
+		text.WriteString("\ncc: ")
+		text.WriteString(e.CC)
+	}
+	if options.Sender || options.Recipient || options.CC {
 		text.WriteString("\n\n")
 	}
 	if options.Subject && threadID == "" {
@@ -125,7 +127,7 @@ func (e *Email) Content(threadID id.EventID, options *ContentOptions) *event.Con
 	}
 
 	parsed := format.RenderMarkdown(text.String(), true, true)
-	parsed.RelatesTo = RelatesTo(options.Threads, threadID)
+	parsed.RelatesTo = utils.RelatesTo(options.Threads, threadID)
 
 	content := event.Content{
 		Raw: map[string]interface{}{
@@ -133,8 +135,10 @@ func (e *Email) Content(threadID id.EventID, options *ContentOptions) *event.Con
 			options.InReplyToKey:  e.InReplyTo,
 			options.ReferencesKey: e.References,
 			options.SubjectKey:    e.Subject,
+			options.RcptToKey:     e.RcptTo,
 			options.FromKey:       e.From,
 			options.ToKey:         e.To,
+			options.CcKey:         e.CC,
 		},
 		Parsed: &parsed,
 	}
@@ -169,13 +173,11 @@ func (e *Email) Compose(privkey string) string {
 
 	root, err := mail.Build()
 	if err != nil {
-		log.Error("cannot compose email: %v", err)
 		return ""
 	}
 	var data strings.Builder
 	err = root.Encode(&data)
 	if err != nil {
-		log.Error("cannot encode email: %v", err)
 		return ""
 	}
 

email/options.go

@@ -0,0 +1,29 @@
+package email
+
+// IncomingFilteringOptions for incoming mail
+type IncomingFilteringOptions interface {
+	SpamcheckSMTP() bool
+	SpamcheckMX() bool
+	Spamlist() []string
+}
+
+// ContentOptions represents settings that specify how an email is to be converted to a Matrix message
+type ContentOptions struct {
+	// On/Off
+	CC        bool
+	Sender    bool
+	Recipient bool
+	Subject   bool
+	HTML      bool
+	Threads   bool
+
+	// Keys
+	MessageIDKey  string
+	InReplyToKey  string
+	ReferencesKey string
+	SubjectKey    string
+	FromKey       string
+	ToKey         string
+	CcKey         string
+	RcptToKey     string
+}

email/utils.go

@@ -0,0 +1,33 @@
+package email
+
+import (
+	"fmt"
+	"net/mail"
+	"regexp"
+	"time"
+
+	"maunium.net/go/mautrix/id"
+)
+
+var styleRegex = regexp.MustCompile("<style((.|\n|\r)*?)<\\/style>")
+
+// AddressValid checks if email address is valid
+func AddressValid(email string) bool {
+	_, err := mail.ParseAddress(email)
+	return err == nil
+}
+
+// MessageID generates email Message-Id from matrix event ID
+func MessageID(eventID id.EventID, domain string) string {
+	return fmt.Sprintf("<%s@%s>", eventID, domain)
+}
+
+// dateNow returns Date in RFC1123 with numeric timezone
+func dateNow(original ...time.Time) string {
+	now := time.Now().UTC()
+	if len(original) > 0 && !original[0].IsZero() {
+		now = original[0]
+	}
+
+	return now.Format(time.RFC1123Z)
+}

go.mod

@@ -22,7 +22,6 @@ require (
 	gitlab.com/etke.cc/go/trysmtp v1.0.0
 	gitlab.com/etke.cc/go/validator v1.0.4
 	gitlab.com/etke.cc/linkpearl v0.0.0-20221116205701-65547c5608e6
-	golang.org/x/net v0.2.0
 	maunium.net/go/mautrix v0.12.3
 )
 
@@ -49,6 +48,7 @@ require (
 	github.com/tidwall/sjson v1.2.5 // indirect
 	github.com/yuin/goldmark v1.5.3 // indirect
 	golang.org/x/crypto v0.3.0 // indirect
+	golang.org/x/net v0.2.0 // indirect
 	golang.org/x/sys v0.2.0 // indirect
 	golang.org/x/text v0.4.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

smtp/manager.go

@@ -11,7 +11,7 @@ import (
 	"gitlab.com/etke.cc/go/logger"
 	"maunium.net/go/mautrix/id"
 
-	"gitlab.com/etke.cc/postmoogle/utils"
+	"gitlab.com/etke.cc/postmoogle/email"
 )
 
 type Config struct {
@@ -45,8 +45,8 @@ type matrixbot interface {
 	IsBanned(net.Addr) bool
 	Ban(net.Addr)
 	GetMapping(string) (id.RoomID, bool)
-	GetIFOptions(id.RoomID) utils.IncomingFilteringOptions
+	GetIFOptions(id.RoomID) email.IncomingFilteringOptions
-	IncomingEmail(context.Context, *utils.Email) error
+	IncomingEmail(context.Context, *email.Email) error
 	SetSendmail(func(string, string, string) error)
 	GetDKIMprivkey() string
 }

smtp/server.go

@@ -10,7 +10,7 @@ import (
 	"gitlab.com/etke.cc/go/logger"
 	"gitlab.com/etke.cc/go/trysmtp"
 
-	"gitlab.com/etke.cc/postmoogle/utils"
+	"gitlab.com/etke.cc/postmoogle/email"
 )
 
 var (
@@ -41,7 +41,7 @@ func (m *mailServer) Login(state *smtp.ConnectionState, username, password strin
 		return nil, ErrBanned
 	}
 
-	if !utils.AddressValid(username) {
+	if !email.AddressValid(username) {
 		m.log.Debug("address %s is invalid", username)
 		m.bot.Ban(state.RemoteAddr)
 		return nil, ErrBanned
@@ -60,6 +60,7 @@ func (m *mailServer) Login(state *smtp.ConnectionState, username, password strin
 		from:     username,
 		log:      m.log,
 		domains:  m.domains,
+		tos:      []string{},
 	}, nil
 }
 
@@ -80,6 +81,7 @@ func (m *mailServer) AnonymousLogin(state *smtp.ConnectionState) (smtp.Session,
 		log:          m.log,
 		domains:      m.domains,
 		addr:         state.RemoteAddr,
+		tos:          []string{},
 	}, nil
 }
 
@@ -112,6 +114,6 @@ func (m *mailServer) SendEmail(from, to, data string) error {
 }
 
 // ReceiveEmail - incoming mail into matrix room
-func (m *mailServer) ReceiveEmail(ctx context.Context, email *utils.Email) error {
+func (m *mailServer) ReceiveEmail(ctx context.Context, eml *email.Email) error {
-	return m.bot.IncomingEmail(ctx, email)
+	return m.bot.IncomingEmail(ctx, eml)
 }

smtp/session.go

@@ -13,6 +13,7 @@ import (
 	"gitlab.com/etke.cc/go/validator"
 	"maunium.net/go/mautrix/id"
 
+	"gitlab.com/etke.cc/postmoogle/email"
 	"gitlab.com/etke.cc/postmoogle/utils"
 )
 
@@ -20,21 +21,21 @@ import (
 type incomingSession struct {
 	log          *logger.Logger
 	getRoomID    func(string) (id.RoomID, bool)
-	getFilters   func(id.RoomID) utils.IncomingFilteringOptions
+	getFilters   func(id.RoomID) email.IncomingFilteringOptions
-	receiveEmail func(context.Context, *utils.Email) error
+	receiveEmail func(context.Context, *email.Email) error
 	greylisted   func(net.Addr) bool
 	ban          func(net.Addr)
 	domains      []string
 
 	ctx  context.Context
 	addr net.Addr
-	to   string
+	tos  []string
 	from string
 }
 
 func (s *incomingSession) Mail(from string, opts smtp.MailOptions) error {
 	sentry.GetHubFromContext(s.ctx).Scope().SetTag("from", from)
-	if !utils.AddressValid(from) {
+	if !email.AddressValid(from) {
 		s.log.Debug("address %s is invalid", from)
 		s.ban(s.addr)
 		return ErrBanned
@@ -46,7 +47,7 @@ func (s *incomingSession) Mail(from string, opts smtp.MailOptions) error {
 
 func (s *incomingSession) Rcpt(to string) error {
 	sentry.GetHubFromContext(s.ctx).Scope().SetTag("to", to)
-	s.to = to
+	s.tos = append(s.tos, to)
 	var domainok bool
 	for _, domain := range s.domains {
 		if utils.Hostname(to) == domain {
@@ -66,7 +67,7 @@ func (s *incomingSession) Rcpt(to string) error {
 	}
 
 	validations := s.getFilters(roomID)
-	if !validateEmail(s.from, s.to, s.log, validations) {
+	if !validateEmail(s.from, to, s.log, validations) {
 		s.ban(s.addr)
 		return ErrBanned
 	}
@@ -84,25 +85,20 @@ func (s *incomingSession) Data(r io.Reader) error {
 		}
 	}
 	parser := enmime.NewParser()
-	eml, err := parser.ReadEnvelope(r)
+	envelope, err := parser.ReadEnvelope(r)
 	if err != nil {
 		return err
 	}
 
-	files := parseAttachments(eml.Attachments, s.log)
+	eml := email.FromEnvelope(s.tos[0], envelope)
-
+	for _, to := range s.tos {
-	email := utils.NewEmail(
+		eml.RcptTo = to
-		eml.GetHeader("Message-Id"),
+		err := s.receiveEmail(s.ctx, eml)
-		eml.GetHeader("In-Reply-To"),
+		if err != nil {
-		eml.GetHeader("References"),
+			return err
-		eml.GetHeader("Subject"),
+		}
-		s.from,
+	}
-		s.to,
+	return nil
-		eml.Text,
-		eml.HTML,
-		files)
-
-	return s.receiveEmail(s.ctx, email)
 }
 func (s *incomingSession) Reset()        {}
 func (s *incomingSession) Logout() error { return nil }
@@ -115,13 +111,13 @@ type outgoingSession struct {
 	domains  []string
 
 	ctx  context.Context
-	to   string
+	tos  []string
 	from string
 }
 
 func (s *outgoingSession) Mail(from string, opts smtp.MailOptions) error {
 	sentry.GetHubFromContext(s.ctx).Scope().SetTag("from", from)
-	if !utils.AddressValid(from) {
+	if !email.AddressValid(from) {
 		return errors.New("please, provide email address")
 	}
 	return nil
@@ -129,7 +125,7 @@ func (s *outgoingSession) Mail(from string, opts smtp.MailOptions) error {
 
 func (s *outgoingSession) Rcpt(to string) error {
 	sentry.GetHubFromContext(s.ctx).Scope().SetTag("to", to)
-	s.to = to
+	s.tos = append(s.tos, to)
 
 	s.log.Debug("mail to %s", to)
 	return nil
@@ -137,30 +133,25 @@ func (s *outgoingSession) Rcpt(to string) error {
 
 func (s *outgoingSession) Data(r io.Reader) error {
 	parser := enmime.NewParser()
-	eml, err := parser.ReadEnvelope(r)
+	envelope, err := parser.ReadEnvelope(r)
 	if err != nil {
 		return err
 	}
+	eml := email.FromEnvelope(s.tos[0], envelope)
+	for _, to := range s.tos {
+		eml.RcptTo = to
+		err := s.sendmail(eml.From, to, eml.Compose(s.privkey))
+		if err != nil {
+			return err
+		}
+	}
 
-	files := parseAttachments(eml.Attachments, s.log)
+	return nil
-
-	email := utils.NewEmail(
-		eml.GetHeader("Message-Id"),
-		eml.GetHeader("In-Reply-To"),
-		eml.GetHeader("References"),
-		eml.GetHeader("Subject"),
-		s.from,
-		s.to,
-		eml.Text,
-		eml.HTML,
-		files)
-
-	return s.sendmail(email.From, email.To, email.Compose(s.privkey))
 }
 func (s *outgoingSession) Reset()        {}
 func (s *outgoingSession) Logout() error { return nil }
 
-func validateEmail(from, to string, log *logger.Logger, options utils.IncomingFilteringOptions) bool {
+func validateEmail(from, to string, log *logger.Logger, options email.IncomingFilteringOptions) bool {
 	enforce := validator.Enforce{
 		Email: true,
 		MX:    options.SpamcheckMX(),
@@ -170,16 +161,3 @@ func validateEmail(from, to string, log *logger.Logger, options utils.IncomingFi
 
 	return v.Email(from)
 }
-
-func parseAttachments(parts []*enmime.Part, log *logger.Logger) []*utils.File {
-	files := make([]*utils.File, 0, len(parts))
-	for _, attachment := range parts {
-		for _, err := range attachment.Errors {
-			log.Warn("attachment error: %v", err)
-		}
-		file := utils.NewFile(attachment.FileName, attachment.Content)
-		files = append(files, file)
-	}
-
-	return files
-}

utils/mail.go

@@ -0,0 +1,41 @@
+package utils
+
+import "strings"
+
+// Mailbox returns mailbox part from email address
+func Mailbox(email string) string {
+	index := strings.LastIndex(email, "@")
+	if index == -1 {
+		return email
+	}
+	return email[:index]
+}
+
+// EmailsList returns human-readable list of mailbox's emails for all available domains
+func EmailsList(mailbox string, domain string) string {
+	var msg strings.Builder
+	domain = SanitizeDomain(domain)
+	msg.WriteString(mailbox)
+	msg.WriteString("@")
+	msg.WriteString(domain)
+
+	count := len(domains) - 1
+	for i, aliasDomain := range domains {
+		if i < count {
+			msg.WriteString(", ")
+		}
+		if aliasDomain == domain {
+			continue
+		}
+		msg.WriteString(mailbox)
+		msg.WriteString("@")
+		msg.WriteString(aliasDomain)
+	}
+
+	return msg.String()
+}
+
+// Hostname returns hostname part from email address
+func Hostname(email string) string {
+	return email[strings.LastIndex(email, "@")+1:]
+}

utils/utils.go

@@ -22,44 +22,6 @@ func SetDomains(slice []string) {
 	domains = slice
 }
 
-// Mailbox returns mailbox part from email address
-func Mailbox(email string) string {
-	index := strings.LastIndex(email, "@")
-	if index == -1 {
-		return email
-	}
-	return email[:index]
-}
-
-// EmailsList returns human-readable list of mailbox's emails for all available domains
-func EmailsList(mailbox string, domain string) string {
-	var msg strings.Builder
-	domain = SanitizeDomain(domain)
-	msg.WriteString(mailbox)
-	msg.WriteString("@")
-	msg.WriteString(domain)
-
-	count := len(domains) - 1
-	for i, aliasDomain := range domains {
-		if i < count {
-			msg.WriteString(", ")
-		}
-		if aliasDomain == domain {
-			continue
-		}
-		msg.WriteString(mailbox)
-		msg.WriteString("@")
-		msg.WriteString(aliasDomain)
-	}
-
-	return msg.String()
-}
-
-// Hostname returns hostname part from email address
-func Hostname(email string) string {
-	return email[strings.LastIndex(email, "@")+1:]
-}
-
 // SanitizeDomain checks that input domain is available for use
 func SanitizeDomain(domain string) string {
 	domain = strings.TrimSpace(domain)