Sympa does not like "`" chars in email addresses within include file

[agouaux]

I noticed error messages like this when sympa tried to sync an include file that had a "`" in the local part of the address. At first I was surprised that Office365 (location of our mailboxes) allowed it, but then I discovered that it was technically OK with the RFCs. (I can re-dig up the references I found if necessary.)

Jun 25 23:20:14 sympa01 sympa[53065]: err main::#849 > Sympa::Spindle::spin#95 > Sympa::Request::Handler::include::_twist#201 > Sympa::Request::Handler::include::_update_users#372 > Sympa::DataSource::next#149 > Sympa::DataSource::File::_next#75 Skip badly formed line: "first1`.last1@x.org First1` Last1"

Version

6.2.60

Installation method

Source (that locally build into our own rpm)

Expected behavior

I think so long as the "`" is in the local part, it should be considered ok, despite it being a bit odd.

Actual behavior

The sync of the include file never completes successfully.

Additional information

[ikedas]

FYI.

Sympa

Currently, Sympa allows the local part of e-mail to include either:
0-9, a-z (case-insensitive), _, -, ., /, +, =, ' or &

or to match:
".*"

And it doesn't allow to include either:
|, $, *, ? nor !

sympa/src/lib/Sympa/Tools/Text.pm

Lines 505 to 515 in e1555fc

	sub valid_email {
	my $email = shift;
	my $email_re = Sympa::Regexps::email();
	return undef unless $email =~ /^${email_re}$/;
	# Forbidden characters.
	return undef if $email =~ /[\|\$\*\?\!]/;
	return 1;
	}

sympa/src/lib/Sympa/Regexps.pm

Lines 33 to 37 in e1555fc

	# This is the same as email below except that it does never give any groups.
	use constant addrspec => qr{(?:[-&+'./\w=]+|".*")\@[-\w]+(?:[.][-\w]+)+};
	# Caution: If this regexp changes (more/less parenthesis), then regexp using
	# it should also be changed. By this reason it would be obsoleted.
	use constant email => qr'([\w\-\_\.\/\+\=\'\&]+|\".*\")\@[\w\-]+(\.[\w\-]+)+';

RFC

OTOH, RFC 5322 allows "dot-atom-text" below in local part (except when it is enclosed in "...") [1]:

   atext           =   ALPHA / DIGIT /    ; Printable US-ASCII
                       "!" / "#" /        ;  characters not including
                       "$" / "%" /        ;  specials.  Used for atoms.
                       "&" / "'" /
                       "*" / "+" /
                       "-" / "/" /
                       "=" / "?" /
                       "^" / "_" /
                       "`" / "{" /
                       "|" / "}" /
                       "~"

   atom            =   [CFWS] 1*atext [CFWS]

   dot-atom-text   =   1*atext *("." 1*atext)

   dot-atom        =   [CFWS] dot-atom-text [CFWS]

   specials        =   "(" / ")" /        ; Special characters that do
                       "<" / ">" /        ;  not appear in atext
                       "[" / "]" /
                       ":" / ";" /
                       "@" / "\" /
                       "," / "." /
                       DQUOTE