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3 commits

Author SHA1 Message Date
David van Moolenbroek
e4d99eb9b0 Basic live rerandomization infrastructure
This commits adds a basic infrastructure to support Address Space
Randomization (ASR).  In a nutshell, using the already imported ASR
LLVM pass, multiple versions can be generated for the same system
service, each with a randomized, different address space layout.
Combined with the magic instrumentation for state transfer, a system
service can be live updated into another ASR-randomized version at
runtime, thus providing live rerandomization.

Since MINIX3 is not yet capable of running LLVM linker passes, the
ASR-randomized service binaries have to be pregenerated during
crosscompilation.  These pregenerated binaries can then be cycled
through at runtime.  This patch provides the basic proof-of-concept
infrastructure for both these parts.

In order to support pregeneration, the clientctl host script has
been extended with a "buildasr" command.  It is to be used after
building the entire system with bitcode and magic support, and will
produce a given number of ASR-randomized versions of all system
services.  These services are placed in /usr/service/asr in the
image that is generated as final step by the "buildasr" command.

In order to support runtime updating, a new update_asr(8) command
has been added to MINIX3.  This command attempts to live-update the
running system services into their next ASR-randomized versions.
For now, this command is not run automatically, and thus must be
invoked manually.

Technical notes:

- For various reasons, magic instrumentation is x86-only for now,
  and ASR functionality is therefore to be used on x86 only as well.
- The ASR-randomized binaries are placed in numbered subdirectories
  so as not to have to change their actual program names, which are
  assumed to be static in various places (system.conf, procfs).
- The root partition is typically too small to contain all the
  produced binaries, which is why we introduce /usr/service.  There
  is a symlink from /service/asr to /usr/service/asr for no other
  reason than to let userland continue to assume that all services
  are reachable through /service.
- The ASR count field (r_asr_count/ASRcount) maintained by RS is not
  used within RS in any way; it is only passed through procfs to
  userland in order to allow update_asr(8) to keep track of which
  version is currently loaded without having to maintain own state.
- Ideally, pre-instrumentation linking of a service would remove all
  its randomized versions.  Currently, the user is assumed not to
  perform ASR instrumentation and then recompile system services
  without performing ASR instrumentation again, as the randomized
  binaries included in the image would then be stale.  This aspect
  has to be improved later.
- Various other issues are flagged in the comments of the various
  parts of this patch.

Change-Id: I093ad57f31c18305591f64b2d491272288aa0937
2015-09-17 17:15:03 +00:00
Lionel Sambuc
84d9c625bf Synchronize on NetBSD-CVS (2013/12/1 12:00:00 UTC)
- Fix for possible unset uid/gid in toproto
 - Fix for default mtree style
 - Update libelf
 - Importing libexecinfo
 - Resynchronize GCC, mpc, gmp, mpfr
 - build.sh: Replace params with show-params.
     This has been done as the make target has been renamed in the same
     way, while a new target named params has been added. This new
     target generates a file containing all the parameters, instead of
     printing it on the console.
 - Update test48 with new etc/services (Fix by Ben Gras <ben@minix3.org)
     get getservbyport() out of the inner loop

Change-Id: Ie6ad5226fa2621ff9f0dee8782ea48f9443d2091
2014-07-28 17:05:06 +02:00
Lionel Sambuc
9152e1c5a7 Upgrading build system to new NetBSD revision
The tested targets are the followgin ones:
 * tools
 * distribution
 * sets
 * release

The remaining NetBSD targets have not been disabled nor tested
*at all*. Try them at your own risk, they may reboot the earth.

For all compliant Makefiles, objects and generated files are put in
MAKEOBJDIR, which means you can now keep objects between two branch
switching. Same for DESTDIR, please refer to build.sh options.

Regarding new or modifications of Makefiles a few things:
 * Read share/mk/bsd.README
 * If you add a subdirectory, add a Makefile in it, and have it called
   by the parent through the SUBDIR variable.
 * Do not add arbitrary inclusion which crosses to another branch of
   the hierarchy; If you can't do without it, put a comment on why.
   If possible, do not use inclusion at all.
 * Use as much as possible the infrastructure, it is here to make
   life easier, do not fight it.

Sets and package are now used to track files.
We have one set called "minix", composed of one package called "minix-sys"
2012-11-15 16:07:29 +01:00