from cinap — add -t flag, unconditional TLS.

Reference: /n/atom/patch/applied2013/smtp-t
Date: Tue Jun 18 03:06:10 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/man/8/smtp	Tue Jun 18 03:05:34 2013
+++ /sys/man/8/smtp	Tue Jun 18 03:05:34 2013
@@ -6,7 +6,7 @@
 .ti -0.5i
 .B upas/smtp
 [
-.B -aAdfips
+.B -aAdfipst
 ] [
 .B -b
 .I busted-mx
@@ -118,6 +118,9 @@
 .B -s
 if the server supports the ESMTP extension to use TLS encryption, turn it on for
 this session.  See RFC3207 for details.
+.TP
+.B -t
+preemtively establish TLS connection before SMTP handshake (SMTPS).
 .TP
 .B -u
 specify a user name to be used in authentication.  The default name is
--- /sys/src/cmd/upas/smtp/smtp.c	Tue Jun 18 03:05:34 2013
+++ /sys/src/cmd/upas/smtp/smtp.c	Tue Jun 18 03:05:34 2013
@@ -6,6 +6,7 @@
 #include <auth.h>
 
 static	char*	connect(char*, Mx*);
+static	char*	wraptls(void);
 static	char*	dotls(char*);
 static	char*	doauth(char*);
 
@@ -52,6 +53,7 @@
 char	*farend;	/* system we are trying to send to */
 char	*user;		/* user we are authenticating as, if authenticating */
 char	hostdomain[256];
+Mx	*tmmx;		/* global for timeout */
 
 Biobuf	bin;
 Biobuf	bout;
@@ -64,41 +66,13 @@
 	Mx *mx;
 
 	mx = va_arg(fmt->args, Mx*);
-	if(mx == nil || mx->host[0] == 0 && mx->ip[0] == 0)
+	if(mx == nil || mx->host[0] == 0)
 		return fmtstrcpy(fmt, "");
-	if((fmt->flags & FmtSharp) == 0)
-		fmtstrcpy(fmt, "(");
-	if(mx->valid == 0)
-		fmtstrcpy(fmt, "!");
-	fmtprint(fmt, "%s:%s;pref=%d", mx->host, mx->ip, mx->pref);
-	if((fmt->flags & FmtSharp) == 0)
-		fmtstrcpy(fmt, ")");
-	return 0;
+	else
+		return fmtprint(fmt, "(%s:%s)", mx->host, mx->ip);
 }
 #pragma	varargck	type	"D"	Mx*
 
-int
-Lfmt(Fmt *fmt)
-{
-	int i;
-	Mxtab *mx;
-
-	mx = va_arg(fmt->args, Mxtab*);
-	if(mx == nil || mx->nmx == 0)
-		return fmtstrcpy(fmt, "");
-	fmtstrcpy(fmt, "(");
-	for(i = 0; i<mx->nmx; i++){
-		if(i == mx->pmx)
-			fmtprint(fmt, "*");
-		fmtprint(fmt, "%#D", mx->mx+i);
-		if(++i == mx->nmx)
-			break;
-		fmtprint(fmt, " ");
-	}
-	return fmtstrcpy(fmt, ")");
-}
-#pragma	varargck	type	"L"	Mxtab*
-
 char*
 deliverytype(void)
 {
@@ -110,7 +84,7 @@
 void
 usage(void)
 {
-	fprint(2, "usage: smtp [-aAdfips] [-b busted-mx] [-g gw] [-h host] "
+	fprint(2, "usage: smtp [-aAdfipst] [-b busted-mx] [-g gw] [-h host] "
 		"[-u user] [.domain] net!host[!service] sender rcpt-list\n");
 	exits(Giveup);
 }
@@ -118,7 +92,7 @@
 int
 timeout(void *, char *msg)
 {
-	syslog(0, "smtp.fail", "%s interrupt: %s: %s", deliverytype(), farend,  msg);
+	syslog(0, "smtp.fail", "%s interrupt: %s: %s %D", deliverytype(), farend,  msg, tmmx);
 	if(strstr(msg, "alarm")){
 		fprint(2, "smtp timeout: connection to %s timed out\n", farend);
 		if(quitting)
@@ -128,7 +102,7 @@
 	if(strstr(msg, "closed pipe")){
 		fprint(2, "smtp timeout: connection closed to %s\n", farend);
 		if(quitting){
-			syslog(0, "smtp.fail", "%s closed pipe to %s", deliverytype(), farend);
+			syslog(0, "smtp.fail", "%s closed pipe to %s %D", deliverytype(), farend, tmmx);
 			_exits(quitrv);
 		}
 		/* call _exits() to prevent Bio from trying to flush closed pipe */
@@ -152,7 +126,7 @@
 main(int argc, char **argv)
 {
 	char *phase, *addr, *rv, *trv, *host, *domain;
-	char **errs, hellodomain[256];
+	char **errs, *p, *e, hellodomain[256], allrx[512];
 	int i, ok, rcvrs, bustedmx;
 	String *from, *fromm, *sender;
 	Mx mx;
@@ -161,7 +135,6 @@
 	quotefmtinstall();
 	mailfmtinstall();		/* 2047 encoding */
 	fmtinstall('D', Dfmt);
-	fmtinstall('L', Lfmt);
 	errs = malloc(argc*sizeof(char*));
 	reply = s_new();
 	host = 0;
@@ -201,6 +174,9 @@
 	case 's':
 		trysecure = 1;
 		break;
+	case 't':
+		trysecure = 2;
+		break;
 	case 'u':
 		user = EARGF(usage());
 		break;
@@ -257,6 +233,7 @@
 	/*
 	 *  send the mail
 	 */
+	rcvrs = 0;
 	phase = "";
 	USED(phase);			/* just in case */
 	if(filter){
@@ -273,10 +250,11 @@
 	if((rv = connect(addr, &mx)) != 0)
 		exits(rv);
 
+	tmmx = &mx;
 	/* 10 minutes to get through the initial handshake */
 	atnotify(timeout, 1);
 	alarm(10*alarmscale);
-	if((rv = hello(hellodomain, 0)) != 0){
+	if((rv = hello(hellodomain, trysecure > 1)) != 0){
 		phase = "hello";
 		goto error;
 	}
@@ -287,7 +265,6 @@
 	}
 
 	ok = 0;
-	rcvrs = 0;
 	/* if any rcvrs are ok, we try to send the message */
 	phase = "rcptto";
 	for(i = 0; i < argc; i++){
@@ -339,9 +316,18 @@
 	 *  here when all rcvrs failed
 	 */
 error:
+	alarm(0);
 	removenewline(s_to_c(reply));
-	syslog(0, "smtp.fail", "%s to %s %D %s failed: %s",
-		deliverytype(), addr, &mx, phase, s_to_c(reply));
+	if(rcvrs > 0){
+		p = allrx;
+		e = allrx + sizeof allrx;
+		seprint(p, e, "to ");
+		for(i = 0; i < rcvrs - 1; i++)
+			p = seprint(p, e, "%s,", argv[i]);
+		seprint(p, e, "%s ", argv[i]);
+	}
+	syslog(0, "smtp.fail", "%s %s at %s %D %s failed: %s",
+		deliverytype(), allrx, addr, &mx, phase, s_to_c(reply));
 	fprint(2, "%s connect to %s %D %s:\n%s\n", thedate(), addr, &mx, phase, s_to_c(reply));
 	if(!filter)
 		quit(rv);
@@ -352,18 +338,17 @@
  *  connect to the remote host
  */
 static char *
-connect(char* net, Mx *x)
+connect(char* net, Mx *mx)
 {
-	char buf[1024];
+	char buf[256];
 	int fd;
-	Mxtab mx;
 
-	memset(x, 0, sizeof *x);
-	fd = mxdial0(net, ddomain, gdomain, &mx);
+	fd = mxdial(net, ddomain, gdomain, mx);
+
 	if(fd < 0){
 		rerrstr(buf, sizeof buf);
-		Bprint(&berr, "smtp: %s (%s) %L\n", buf, net, &mx);
-		syslog(0, "smtp.fail", "%s %s (%s) %L", deliverytype(), buf, net, &mx);
+		Bprint(&berr, "smtp: %s (%s) %D\n", buf, net, mx);
+		syslog(0, "smtp.fail", "%s %s (%s) %D", deliverytype(), buf, net, mx);
 		if(strstr(buf, "illegal")
 		|| strstr(buf, "unknown")
 		|| strstr(buf, "can't translate"))
@@ -371,9 +356,6 @@
 		else
 			return Retry;
 	}
-	*x = mx.mx[mx.pmx];
-	/* mxtabfree(&mx);	 but for .netdir */
-
 	Binit(&bin, fd, OREAD);
 	fd = dup(fd, -1);
 	Binit(&bout, fd, OWRITE);
@@ -383,13 +365,8 @@
 static char smtpthumbs[] =	"/sys/lib/tls/smtp";
 static char smtpexclthumbs[] =	"/sys/lib/tls/smtp.exclude";
 
-/*
- *  exchange names with remote host, attempt to
- *  enable encryption and optionally authenticate.
- *  not fatal if we can't.
- */
-static char *
-dotls(char *me)
+static char*
+wraptls(void)
 {
 	char *h;
 	int fd;
@@ -397,24 +374,21 @@
 	TLSconn *c;
 	Thumbprint *goodcerts;
 
-	c = mallocz(sizeof(*c), 1);	/* Note: not freed on success */
+	c = mallocz(sizeof(*c), 1);
 	if(c == nil)
 		return Giveup;
 
-	dBprint("STARTTLS\r\n");
-	if(getreply() != 2)
-		return Giveup;
-
 	fd = tlsClient(Bfildes(&bout), c);
 	if(fd < 0){
 		syslog(0, "smtp", "tlsClient to %q: %r", ddomain);
+		free(c);
 		return Giveup;
 	}
 	goodcerts = initThumbprints(smtpthumbs, smtpexclthumbs);
 	if(goodcerts == nil){
-		free(c);
-		close(fd);
 		syslog(0, "smtp", "bad thumbprints in %s", smtpthumbs);
+		close(fd);
+		free(c);
 		return Giveup;		/* how to recover? TLS is started */
 	}
 
@@ -422,8 +396,6 @@
 	sha1(c->cert, c->certlen, hash, nil);
 	if(!okThumbprint(hash, goodcerts)){
 		/* TODO? if not excluded, add hash to thumb list */
-		free(c);
-		close(fd);
 		h = malloc(2*sizeof hash + 1);
 		if(h != nil){
 			enc16(h, 2*sizeof hash + 1, hash, sizeof hash);
@@ -433,9 +405,12 @@
 				h, ddomain);
 			free(h);
 		}
+		close(fd);
+		free(c);
 		return Giveup;		/* how to recover? TLS is started */
 	}
 	freeThumbprints(goodcerts);
+	free(c);
 	Bterm(&bin);
 	Bterm(&bout);
 
@@ -448,6 +423,27 @@
 	Binit(&bout, fd, OWRITE);
 
 	syslog(0, "smtp", "started TLS to %q", ddomain);
+	return nil;
+}
+
+/*
+ *  exchange names with remote host, attempt to
+ *  enable encryption and optionally authenticate.
+ *  not fatal if we can't.
+ */
+static char *
+dotls(char *me)
+{
+	char *err;
+
+	dBprint("STARTTLS\r\n");
+	if (getreply() != 2)
+		return Giveup;
+
+	err = wraptls();
+	if (err != nil)
+		return err;
+
 	return(hello(me, 1));
 }
 
@@ -464,8 +460,6 @@
 		return Retry;
 	p = s_to_c(reply) + 4;
 	l = dec64((uchar*)ch, sizeof ch, p, strlen(p));
-	if(l == -1)
-		return Retry;
 	ch[l] = 0;
 
 	e = abuf + sizeof abuf;