On 01/13/13 09:13, Konstantin Belousov wrote: > On Sun, Jan 13, 2013 at 08:21:37AM -0800, Nathan Whitehorn wrote: >> On 01/13/13 05:20, Konstantin Belousov wrote: >>> On Sun, Jan 13, 2013 at 12:41:09PM +0100, Ed Schouten wrote: >>>> Hi Kostik, >>>> >>>> 2013/1/7 Konstantin Belousov <kostik...@gmail.com>: >>>>> I still do remember the buzz about the binary format 0xCAFEBABE, which >>>>> AFAIR gained image activator support on several OSes, to be garbage >>>>> collected. >>>> >>>> Maybe it would then be a good idea then to add some kind of general >>>> purpose remapping imgact? Example: >>>> >>>> /etc/imgacttab: >>>> >>>> cafebabe /usr/local/bin/java >>>> cffaedfe /usr/local/bin/osx_emulator >>>> 4243c0de /usr/bin/lli >>>> >>>> That way we still give people the freedom to play around with mapping >>>> their own executable formats, but don't need to maintain a bunch of >>>> imgacts. >>> >>> A generic module that could be somewhat customized at runtime to map >>> offset+signature into the shebang path could be a possibility indeed. >>> I strongly prefer to have it as module and not enabled by default. >>> >>> Asking Nathan for writing the thing is too much, IMHO, esp. in >>> the response to the 50-lines hack. >>> >> >> I think this is a good idea, since it both prevents a profusion of >> similar activators and works nicely in jails and similar environments. I >> probably won't write it quickly, but it should not take more than about >> 50 lines, so I can't imagine it will be that bad. There are some >> complications with this kind of design from the things in the XXX >> comment in imgact_llvm.c about handling argv[0] that I need to think >> some more about. > Great. I do not believe in the 50 lines, but I am happy that you want > to work this out. > >> >> Why are you opposed to having it there by default? I think it's actually >> quite important that it be there by default. Having it not "standard" >> would be fine, but it should at least be in GENERIC. There are minimal >> security risks since it just munges begin_argv and doesn't even load the >> executable and it's little enough code that there should not be any >> kernel bloat to speak of. If things like this aren't enabled by default, >> no one can depend on them being there, no one will use it, and the point >> is entirely lost. > All image activators demonstrated a constant stream of security holes. > Even our ELF activator, and I was guilty there too. > > I definitely do not fight over the inclusion of the proposed activator > into GENERIC, but do insist on the config option + module. >
OK, that sounds like a plan then. I'll try to code up something configurable in the next couple weeks, unless someone else beats me to it. -Nathan _______________________________________________ freebsd-toolchain@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-toolchain To unsubscribe, send any mail to "freebsd-toolchain-unsubscr...@freebsd.org"
