From 770215dbfdffd0a37d0c051092ae441070eec260 Mon Sep 17 00:00:00 2001
From: Luke Shumaker <lukeshu@sbcglobal.net>
Date: Fri, 10 Feb 2017 00:41:17 -0500
Subject: learn SMTP STARTTLS

---
 Makefile           |  4 ++--
 config-sockets.txt | 17 ++++++++++++-----
 tls-getcerts.go    | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 61 insertions(+), 7 deletions(-)

diff --git a/Makefile b/Makefile
index 43520a6..d175cc3 100644
--- a/Makefile
+++ b/Makefile
@@ -6,10 +6,10 @@ all: index.html style.css jarmon-style/jquerytools.tabs.tabs-no-images.css jarmo
 index.html: tls.html.part crtsh.html.part diff.html.part jarmon.html.part
 
 crtsh.pem: crtsh-getcerts config-domains.txt NET-crtsh
-	./crtsh-getcerts $$(cat config-domains.txt) > $@
+	./crtsh-getcerts $$(sed 's/#.*//' config-domains.txt) > $@
 
 tls.pem: tls-getcerts config-sockets.txt NET-tls
-	./tls-getcerts $$(cat config-sockets.txt) > $@
+	./tls-getcerts $$(sed 's/#.*//' config-sockets.txt) > $@
 
 diff.pem: diff tls.pem crtsh.pem
 	./diff tls.pem crtsh.pem > $@
diff --git a/config-sockets.txt b/config-sockets.txt
index c064f2b..4e40ab9 100644
--- a/config-sockets.txt
+++ b/config-sockets.txt
@@ -1,7 +1,14 @@
-tcp://proton.parabola.nu:443
+tcp://parabola.nu:5222/xmpp
+#tcp://proton.parabola.nu:443
 tcp://proton.parabola.nu:465
+tcp://proton.parabola.nu:587/smtp
+
 tcp://winston.parabola.nu:443
-tcp://lukeshu.com:443
-tcp://team4272.com:443
-tcp://parabola.nu:5222/xmpp
-tcp://andrewdm.me:443
+
+tcp://ramhost.lukeshu.com:443
+
+tcp://mav.lukeshu.com:443
+#tcp://mav.lukeshu.com:25/smtp
+tcp://mav.lukeshu.com:587/smtp
+
+tcp://neo.andrewdm.me:443
diff --git a/tls-getcerts.go b/tls-getcerts.go
index d598d27..d386b90 100644
--- a/tls-getcerts.go
+++ b/tls-getcerts.go
@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"io"
 	"net"
+	"net/textproto"
 	"net/url"
 	"os"
 	"strings"
@@ -62,6 +63,47 @@ func xmppStartTLS(connRaw net.Conn, host string) error {
 	return nil
 }
 
+// smtpCmd is a convenience function that sends a command, and reads
+// (but discards) the response
+func smtpCmd(tp *textproto.Conn, expectCode int, format string, args ...interface{}) error {
+	id, err := tp.Cmd(format, args...)
+	if err != nil {
+		return err
+	}
+	tp.StartResponse(id)
+	defer tp.EndResponse(id)
+	_, _, err = tp.ReadResponse(expectCode)
+	return err
+}
+
+func smtpStartTLS(connRaw net.Conn, host string) error {
+	tp := textproto.NewConn(connRaw)
+
+	// let the server introduce itself
+	_, _, err := tp.ReadResponse(220)
+	if err != nil {
+		return err
+	}
+	// introduce ourself
+	localhost, err := os.Hostname()
+	if err != nil {
+		localhost = "localhost"
+	}
+	err = smtpCmd(tp, 250, "EHLO %s", localhost)
+	if err != nil {
+		err := smtpCmd(tp, 250, "HELO %s", localhost)
+		if err != nil {
+			return err
+		}
+	}
+	// starttls
+	err = smtpCmd(tp, 220, "STARTTLS")
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func getcert(socket string) (*x509.Certificate, error) {
 	u, err := url.Parse(socket)
 	if err != nil {
@@ -85,6 +127,11 @@ func getcert(socket string) (*x509.Certificate, error) {
 		if err != nil {
 			return nil, err
 		}
+	case "/smtp":
+		err = smtpStartTLS(connRaw, host)
+		if err != nil {
+			return nil, err
+		}
 	default:
 		return nil, fmt.Errorf("Unknown negotiation path: %q", u.Path)
 	}
-- 
cgit v1.2.3-54-g00ecf