On Sun, Apr 03, 2016 at 06:28:21PM +0200, Sebastien Marie wrote:
> On Sun, Apr 03, 2016 at 06:09:21PM +0200, frit...@alokat.org wrote:
> > On Sat, Apr 02, 2016 at 04:38:10PM +0200, frit...@alokat.org wrote:
> > > Hi,
> > >
> > > this adds pledge(2) to ftpd(8).
> > >
> > > --f.
> > >
> >
> > With help from semarie@ the original diff was changed a little
> > bit.
> >
> > The following processes are pledged:
> > - [priv post-auth]
> > - User-privileged slave
> > - Unprivileged slave
> >
> > As I don't cover all use cases, please send me your feedback.
> >
> > --f.
> >
> > Index: monitor.c
> > ===================================================================
> > RCS file: /cvs/src/libexec/ftpd/monitor.c,v
> > retrieving revision 1.23
> > diff -u -r1.23 monitor.c
> > --- monitor.c 16 Nov 2015 17:31:14 -0000 1.23
> > +++ monitor.c 3 Apr 2016 15:42:21 -0000
> > @@ -193,6 +193,10 @@
> >
> > endpwent();
> > close(fd_slave);
> > +
> > + if (pledge("stdio", NULL) == -1)
> > + fatalx("pledge");
> > +
> > return (1);
> > }
> >
> > @@ -302,6 +306,11 @@
> > case AUTH_SLAVE:
> > /* User-privileged slave */
> > debugmsg("user-privileged slave started");
> > +
> > + if (pledge("stdio rpath getpw proc wpath cpath
> > inet ioctl sendfd recvfd",
> > + NULL) == -1) {
> > + fatalx("pledge");
> > + }
>
> whoa, still a big list of promises, and some are a bit unexpected for
> me. could you explain the need for them ?
>
> I mean, if "rpath wpath cpath" are expected for a daemon that serve
> files, "ioctl" for example is more questionable. could you explain
> quickly why or where ftpd needs them ?
>
- sendfd / recvfd are for active ftp
- ioctl is e.g. used for "ls" after ftp(1) established a connection
I'm not exactly sure why, as there is no ioctl(2) call, but maybe
in one underlaying library.
- proc for fork e.g. (popen_ftpd.c)
- getpwnam for getpwname(3) e.g. in ftpd.c
> thanks.
>
> > return;
> > /* NOTREACHED */
> > case AUTH_MONITOR:
> > @@ -311,6 +320,11 @@
> > setproctitle("%s: [priv post-auth]",
> > remotehost);
> > slavequit = 1;
> > +
> > + if (pledge("stdio proc dns inet sendfd",
> > + NULL) == -1) {
> > + fatalx("pledge");
> > + }
> >
> > send_data(fd_slave, &slavequit,
> > sizeof(slavequit));
> >
> >
>
> --
> Sebastien Marie
>
