smtp: replace smtp-starttls with schema option

The "smtp-starttls" options is now ignored in favor of more detailed
schema specification, similarly to IMAP.

Fixes: https://todo.sr.ht/~rjarry/aerc/149
Signed-off-by: Marcin Serwin <marcin.serwin0@protonmail.com>
Acked-by: Robin Jarry <robin@jarry.cc>

4 files changed, 53 insertions, 55 deletions

diff --git a/commands/compose/send.go b/commands/compose/send.go
index 4eceefe9..a5571e37 100644
--- a/commands/compose/send.go
+++ b/commands/compose/send.go
@@ -89,28 +89,22 @@ func (Send) Execute(aerc *widgets.Aerc, args []string) error {
 	if err != nil {
 		return err
 	}
-	var starttls bool
-	if starttls_, ok := config.Params["smtp-starttls"]; ok {
-		starttls = starttls_ == "yes"
-	}
 	var domain string
 	if domain_, ok := config.Params["smtp-domain"]; ok {
 		domain = domain_
 	}
 	ctx := sendCtx{
-		uri:      uri,
-		scheme:   scheme,
-		auth:     auth,
-		starttls: starttls,
-		from:     config.From,
-		rcpts:    rcpts,
-		domain:   domain,
+		uri:    uri,
+		scheme: scheme,
+		auth:   auth,
+		from:   config.From,
+		rcpts:  rcpts,
+		domain: domain,
 	}
 
 	log.Debugf("send config uri: %s", ctx.uri)
 	log.Debugf("send config scheme: %s", ctx.scheme)
 	log.Debugf("send config auth: %s", ctx.auth)
-	log.Debugf("send config starttls: %s", ctx.starttls)
 	log.Debugf("send config from: %s", ctx.from)
 	log.Debugf("send config rcpts: %s", ctx.rcpts)
 	log.Debugf("send config domain: %s", ctx.domain)
@@ -171,6 +165,8 @@ func send(aerc *widgets.Aerc, composer *widgets.Composer, ctx sendCtx,
 		switch ctx.scheme {
 		case "smtp":
 			fallthrough
+		case "smtp+insecure":
+			fallthrough
 		case "smtps":
 			sender, err = newSmtpSender(ctx)
 		case "":
@@ -243,13 +239,12 @@ func listRecipients(h *mail.Header) ([]*mail.Address, error) {
 }
 
 type sendCtx struct {
-	uri      *url.URL
-	scheme   string
-	auth     string
-	starttls bool
-	from     *mail.Address
-	rcpts    []*mail.Address
-	domain   string
+	uri    *url.URL
+	scheme string
+	auth   string
+	from   *mail.Address
+	rcpts  []*mail.Address
+	domain string
 }
 
 func newSendmailSender(ctx sendCtx) (io.WriteCloser, error) {
@@ -306,8 +301,15 @@ func parseScheme(uri *url.URL) (scheme string, auth string, err error) {
 		case 1:
 			scheme = parts[0]
 		case 2:
-			scheme = parts[0]
-			auth = parts[1]
+			if parts[1] == "insecure" {
+				scheme = uri.Scheme
+			} else {
+				scheme = parts[0]
+				auth = parts[1]
+			}
+		case 3:
+			scheme = parts[0] + "+" + parts[1]
+			auth = parts[2]
 		default:
 			return "", "", fmt.Errorf("Unknown transfer protocol %s", uri.Scheme)
 		}
@@ -407,7 +409,9 @@ func newSmtpSender(ctx sendCtx) (io.WriteCloser, error) {
 	)
 	switch ctx.scheme {
 	case "smtp":
-		conn, err = connectSmtp(ctx.starttls, ctx.uri.Host, ctx.domain)
+		conn, err = connectSmtp(true, ctx.uri.Host, ctx.domain)
+	case "smtp+insecure":
+		conn, err = connectSmtp(false, ctx.uri.Host, ctx.domain)
 	case "smtps":
 		conn, err = connectSmtps(ctx.uri.Host)
 	default:
@@ -468,11 +472,11 @@ func connectSmtp(starttls bool, host string, domain string) (*smtp.Client, error
 			return nil, errors.Wrap(err, "Hello")
 		}
 	}
-	if sup, _ := conn.Extension("STARTTLS"); sup {
-		if !starttls {
-			err := errors.New("STARTTLS is supported by this server, " +
-				"but not set in accounts.conf. " +
-				"Add smtp-starttls=yes")
+	if starttls {
+		if sup, _ := conn.Extension("STARTTLS"); !sup {
+			err := errors.New("STARTTLS requested, but not supported " +
+				"by this SMTP server. Is someone tampering with your " +
+				"connection?")
 			conn.Close()
 			return nil, err
 		}
@@ -482,13 +486,8 @@ func connectSmtp(starttls bool, host string, domain string) (*smtp.Client, error
 			conn.Close()
 			return nil, errors.Wrap(err, "StartTLS")
 		}
-	} else if starttls {
-		err := errors.New("STARTTLS requested, but not supported " +
-			"by this SMTP server. Is someone tampering with your " +
-			"connection?")
-		conn.Close()
-		return nil, err
 	}
+
 	return conn, nil
 }
 
diff --git a/config/accounts.go b/config/accounts.go
index 8aadb329..bacd7e39 100644
--- a/config/accounts.go
+++ b/config/accounts.go
@@ -161,6 +161,16 @@ func parseAccounts(root string, accts []string) error {
 				account.Params[key] = val
 			}
 		}
+		if _, ok := account.Params["smtp-starttls"]; ok {
+			Warnings = append(Warnings, Warning{
+				Title: "accounts.conf: smtp-starttls is deprecated",
+				Body: `
+SMTP connections now use STARTTLS by default and the smtp-starttls setting is ignored.
+
+If you want to disable STARTTLS, append +insecure to the schema.
+`,
+			})
+		}
 		if account.Source == "" {
 			return fmt.Errorf("Expected source for account %s", _sec)
 		}
diff --git a/doc/aerc-smtp.5.scd b/doc/aerc-smtp.5.scd
index 850a71b2..88fb6629 100644
--- a/doc/aerc-smtp.5.scd
+++ b/doc/aerc-smtp.5.scd
@@ -15,14 +15,17 @@ SMTP configuration may be done interactively with the *:new-account* command.
 In _accounts.conf_ (see *aerc-accounts*(5)), the following SMTP-specific options
 are available:
 
-*outgoing* = _<scheme>_+_<auth>_://_<username>_[_:<password>_]_@<hostname>_[_:<port>_]?[_<oauth2_params>_]
+*outgoing* = _<scheme>_[_+<auth>_]://_<username>_[_:<password>_]_@<hostname>_[_:<port>_]?[_<oauth2_params>_]
 	Remember that all fields must be URL encoded. The _@_ symbol, when URL
 	encoded, is _%40_.
 
 	The value of _<scheme>_ can be:
 
 	_smtp_
-		Unencrypted SMTP
+		SMTP with STARTTLS
+
+	_smtp+insecure_
+		SMTP without STARTTLS
 
 	_smtps_
 		SMTP with TLS/SSL
@@ -58,12 +61,6 @@ are available:
 	Example:
 		outgoing-cred-cmd = pass hostname/username
 
-*smtp-starttls* = _true_|_false_
-	Set this to _true_ if the server uses STARTTLS. In that case you should
-	also use _smtp://_ instead of _smtps://_.
-
-	Default: _false_
-
 *smtp-domain* = _<domain>_
 	Local domain name to use in the HELO/EHLO SMTP command. Set this to a fully
 	qualified domain name if the server requires it as an antispam measure.
diff --git a/widgets/account-wizard.go b/widgets/account-wizard.go
index c1d237ef..60497f83 100644
--- a/widgets/account-wizard.go
+++ b/widgets/account-wizard.go
@@ -99,11 +99,11 @@ func NewAccountWizard(aerc *Aerc) *AccountWizard {
 		fullName:     ui.NewTextInput("", config.Ui).Prompt("> "),
 		imapPassword: ui.NewTextInput("", config.Ui).Prompt("] ").Password(true),
 		imapServer:   ui.NewTextInput("", config.Ui).Prompt("> "),
-		imapStr:      ui.NewText("imaps://", config.Ui.GetStyle(config.STYLE_DEFAULT)),
+		imapStr:      ui.NewText("Connection URL: imaps://", config.Ui.GetStyle(config.STYLE_DEFAULT)),
 		imapUsername: ui.NewTextInput("", config.Ui).Prompt("> "),
 		smtpPassword: ui.NewTextInput("", config.Ui).Prompt("] ").Password(true),
 		smtpServer:   ui.NewTextInput("", config.Ui).Prompt("> "),
-		smtpStr:      ui.NewText("smtps://", config.Ui.GetStyle(config.STYLE_DEFAULT)),
+		smtpStr:      ui.NewText("Connection URL: smtps://", config.Ui.GetStyle(config.STYLE_DEFAULT)),
 		smtpUsername: ui.NewTextInput("", config.Ui).Prompt("> "),
 	}
 
@@ -513,10 +513,7 @@ func (wizard *AccountWizard) finish(tutorial bool) {
 	sec.NewKey("source", wizard.imapUrl.String())   //nolint:errcheck // can't fail. option shadowing is not enabled and the key is not empty
 	sec.NewKey("outgoing", wizard.smtpUrl.String()) //nolint:errcheck // can't fail. option shadowing is not enabled and the key is not empty
 	sec.NewKey("default", "INBOX")                  //nolint:errcheck // can't fail. option shadowing is not enabled and the key is not empty
-	if wizard.smtpMode == SMTP_STARTTLS {
-		sec.NewKey("smtp-starttls", "yes") //nolint:errcheck // can't fail. option shadowing is not enabled and the key is not empty
-	}
-	sec.NewKey("from", fmt.Sprintf("%s <%s>", //nolint:errcheck // can't fail. option shadowing is not enabled and the key is not empty
+	sec.NewKey("from", fmt.Sprintf("%s <%s>",       //nolint:errcheck // can't fail. option shadowing is not enabled and the key is not empty
 		wizard.fullName.String(), wizard.email.String()))
 	if wizard.copySent {
 		sec.NewKey("copy-to", "Sent") //nolint:errcheck // can't fail. option shadowing is not enabled and the key is not empty
@@ -547,11 +544,6 @@ func (wizard *AccountWizard) finish(tutorial bool) {
 		Source:   sec.Key("source").String(),
 		Outgoing: config.RemoteConfig{Value: sec.Key("outgoing").String()},
 	}
-	if wizard.smtpMode == SMTP_STARTTLS {
-		account.Params = map[string]string{
-			"smtp-starttls": "yes",
-		}
-	}
 	if wizard.copySent {
 		account.CopyTo = "Sent"
 	}
@@ -635,11 +627,11 @@ func (wizard *AccountWizard) smtpUri() url.URL {
 	var scheme string
 	switch wizard.smtpMode {
 	case SMTP_OVER_TLS:
-		scheme = "smtps+plain"
+		scheme = "smtps"
 	case SMTP_STARTTLS:
-		scheme = "smtp+plain"
+		scheme = "smtp"
 	case SMTP_INSECURE:
-		scheme = "smtp+plain"
+		scheme = "smtp+insecure"
 	}
 	var (
 		userpass   *url.Userinfo