accountd: replace internal option --conn-fd=FD with flag --stdio.

Using stdin/stdout makes it possible to tunnel the accountd connection
through ssh.

1 files changed, 11 insertions, 16 deletions

diff --git a/lacme-accountd b/lacme-accountd
index c00530f..7b9b1ff 100755
--- a/lacme-accountd
+++ b/lacme-accountd
@@ -60,7 +60,7 @@ sub usage(;$$) {
     }
     exit $rv;
 }
-usage(1) unless GetOptions(\%OPTS, qw/config=s privkey=s socket=s conn-fd=i quiet|q debug help|h/);
+usage(1) unless GetOptions(\%OPTS, qw/config=s privkey=s socket=s stdio quiet|q debug help|h/);
 usage(0) if $OPTS{help};
 
 do {
@@ -137,11 +137,7 @@ my $JWK_STR = JSON::->new->encode($JWK);
 # to support the abstract namespace.)  The downside is that we have to
 # delete the file manually.
 #
-if (defined $OPTS{'conn-fd'}) {
-    die "Invalid file descriptor" unless $OPTS{'conn-fd'} =~ /\A(\d+)\z/;
-    # untaint and fdopen(3) our end of the socket pair
-    open ($S, '+<&=', $1+0) or die "fdopen($1): $!";
-} else {
+unless (defined $OPTS{stdio}) {
     my $sockname = $OPTS{socket} // (defined $ENV{XDG_RUNTIME_DIR} ? "$ENV{XDG_RUNTIME_DIR}/S.lacme" : undef);
     die "Missing socket option\n" unless defined $sockname;
     $sockname = $sockname =~ /\A(\p{Print}+)\z/ ? $1 : die "Invalid socket name\n"; # untaint $sockname
@@ -169,22 +165,21 @@ if (defined $OPTS{'conn-fd'}) {
 # For each new connection, send the protocol version and the account key's
 # public parameters, then sign whatever comes in
 #
-sub conn($;$) {
-    my $conn = shift;
-    my $count = shift;
-    $conn->printflush( "$PROTOCOL_VERSION OK", "\r\n", $JWK_STR, "\r\n" ) or warn "print: $!";
+sub conn($$;$) {
+    my ($in, $out, $id) = @_;
+    $out->printflush( "$PROTOCOL_VERSION OK", "\r\n", $JWK_STR, "\r\n" ) or warn "print: $!";
 
     # sign whatever comes in
-    while (defined (my $data = $conn->getline())) {
+    while (defined (my $data = $in->getline())) {
         $data =~ s/\r\n\z// or die;
-        print STDERR "[$count] >>> Issuing SHA-256 signature for: $data\n" unless $OPTS{quiet};
+        print STDERR "[$id] >>> Issuing SHA-256 signature for: $data\n" unless $OPTS{quiet};
         my $sig = $SIGN->($data);
-        $conn->printflush( encode_base64url($sig), "\r\n" ) or warn "print: $!";
+        $out->printflush( encode_base64url($sig), "\r\n" ) or warn "print: $!";
     }
 }
 
-if (defined $OPTS{'conn-fd'}) {
-    conn($S, $$);
+if (defined $OPTS{stdio}) {
+    conn(\*STDIN, \*STDOUT, $$);
 } else {
     $SIG{PIPE} = 'IGNORE'; # ignore broken pipes
     for (my $count = 0;; $count++) {
@@ -193,7 +188,7 @@ if (defined $OPTS{'conn-fd'}) {
             die "accept: $!";
         };
         print STDERR "[$count] >>> Accepted new connection\n" unless $OPTS{quiet};
-        conn($conn, $count);
+        conn($conn, $conn, $count);
         print STDERR "[$count] >>> Connection terminated\n" unless $OPTS{quiet};
         $conn->close() or warn "close: $!";
     }