smtp: Support the SMTPUTF8 extension in the MAIL command

Support the SMTPUTF8 extension when sending mailbox information in the
MAIL command (FROM and AUTH parameters). Non-ASCII domain names will
be ACE encoded, if IDN is supported, whilst non-ASCII characters in
the local address part are passed to the server.

Reported-by: ygthien on github
Fixes #4828

3 files changed, 75 insertions, 6 deletions

diff --git a/tests/data/Makefile.inc b/tests/data/Makefile.inc
index 5215f442f..4ddfeef36 100644
--- a/tests/data/Makefile.inc
+++ b/tests/data/Makefile.inc
@@ -109,7 +109,7 @@ test927 test928 test929 test930 test931 test932 test933 test934 test935 \
 test936 test937 test938 test939 test940 test941 test942 test943 test944 \
 test945 test946 test947 test948 test949 test950 test951 test952 test953 \
 test954 test955 test956 test957 test958 test959 test960 test961 test962 \
-test963 test964 \
+test963 test964 test965 \
 \
 test1000 test1001 test1002 test1003 test1004 test1005 test1006 test1007 \
 test1008 test1009 test1010 test1011 test1012 test1013 test1014 test1015 \
diff --git a/tests/data/test965 b/tests/data/test965
new file mode 100644
index 000000000..4edfd7827
--- /dev/null
+++ b/tests/data/test965
@@ -0,0 +1,65 @@
+<testcase>
+<info>
+<keywords>
+SMTP
+IDN
+</keywords>
+</info>
+
+#
+# Server-side
+<reply>
+<servercmd>
+CAPA SMTPUTF8
+</servercmd>
+</reply>
+
+#
+# Client-side
+<client>
+<server>
+smtp
+</server>
+<features>
+idn
+</features>
+<setenv>
+LC_ALL=en_US.UTF-8
+LC_CTYPE=en_US.UTF-8
+</setenv>
+<precheck>
+perl -MI18N::Langinfo=langinfo,CODESET -e 'die "Needs a UTF-8 locale" if (lc(langinfo(CODESET())) ne "utf-8");'
+</precheck>
+ <name>
+SMTP with SMTPUTF8 support - UTF-8 based sender
+ </name>
+<stdin>
+From: different

+To: another

+

+body

+</stdin>
+<command>
+smtp://%HOSTIP:%SMTPPORT/965 --mail-rcpt recipient@example.com --mail-from Avsändaren@åäö.se -T -
+</command>
+</client>
+
+#
+# Verify data after the test has been "shot"
+<verify>
+<protocol>
+EHLO 965

+MAIL FROM:<Avsändaren@xn--4cab6c.se> SMTPUTF8

+RCPT TO:<recipient@example.com>

+DATA

+QUIT

+</protocol>
+<upload>
+From: different

+To: another

+

+body

+.

+</upload>
+</verify>
+</testcase>
diff --git a/tests/ftpserver.pl b/tests/ftpserver.pl
index 59a1665bd..fe74f8b07 100755
--- a/tests/ftpserver.pl
+++ b/tests/ftpserver.pl
@@ -813,6 +813,7 @@ sub MAIL_smtp {
     else {
         my $from;
         my $size;
+        my $smtputf8 = grep /^SMTPUTF8$/, @capabilities;
         my @elements = split(/ /, $args);
 
         # Get the FROM and SIZE parameters
@@ -827,11 +828,11 @@ sub MAIL_smtp {
 
         # Validate the from address (only <> and a valid email address inside
         # <> are allowed, such as <user@example.com>)
-        if ((!$from) || (($from ne "<>") && ($from !~
-            /^<([a-zA-Z0-9._%+-]+)\@(([a-zA-Z0-9-]+)\.)+([a-zA-Z]{2,4})>$/))) {
-            sendcontrol "501 Invalid address\r\n";
-        }
-        else {
+        if (($from eq "<>") ||
+            (!$smtputf8 && $from =~
+              /^<([a-zA-Z0-9._%+-]+)\@(([a-zA-Z0-9-]+)\.)+([a-zA-Z]{2,4})>$/) ||
+            ($smtputf8 && $from =~
+              /^<([a-zA-Z0-9\x{80}-\x{ff}._%+-]+)\@(([a-zA-Z0-9\x{80}-\x{ff}-]+)\.)+([a-zA-Z]{2,4})>$/)) {
             my @found;
             my $valid = 1;
 
@@ -852,6 +853,9 @@ sub MAIL_smtp {
                 sendcontrol "250 Sender OK\r\n";
             }
         }
+        else {
+            sendcontrol "501 Invalid address\r\n";
+        }
     }
 
     return 0;