But there are SO many chipsets they put out. e.g. I have a Core 2 Duo system,
but the exact chipset is T9400.

Intel could keep track of which chipsets are vulnerable and which are not, and
carefully pick which kind gets released to who.

Obviously, Intel employees aware of the strategy would only use the
invulnerable chipsets themselves.

------
lmm
I'm expecting someone to produce a fully open hardware stack sooner or later -
there's already a freely available sparc processor design, and I recall some
open-source people working on a fully open graphics card. (Of course you still
have to trust your fab, but that's not very different from trusting your
compiler).

~~~
andylei
how is trusting your fab any different than trusting Intel?

> that's not very different from trusting your compiler

if you were paranoid enough to be worrying about CPU backdoors, why would you
trust your compiler?

~~~
lmm
>how is trusting your fab any different than trusting Intel?

You increase the cost of an attack - it's harder to change a processor's
behavior by editing the mask than the VHDL. If you were super-paranoid you
could source to multiple different fabs and run the chips you get back in
parallel, with some sort of trap that goes off whenever you get different
results from one or other processor.

>if you were paranoid enough to be worrying about CPU backdoors, why would you
trust your compiler?

If you don't trust your compiler, why are you even bothering worrying about
CPU backdoors when you've got a much easier attack vector open?

~~~
javert
_run the chips you get back in parallel_

Who's to say you're going to trigger the condition that causes the backdoor?
Seems very unlikely. If you have ideas on this, though, I'd be interested.

 _If you don't trust your compiler, why are you even bothering worrying about
CPU backdoors when you've got a much easier attack vector open?_

You may not trust your compiler, and therefore do certain things in a VM where
e.g. access to network is limited. See [1].

[1] <http://qubes-os.org/Home.html>

But there are SO many chipsets they put out. e.g. I get a Core 2 couple system, 
 but the exact chipset is T9400. 

 Intel could keep lead of which chipsets are vulnerable and which are not, and 
 carefully pick which kind gets exhaust to who. 

 Obviously, Intel employees aware of the scheme would merely use the 
 invulnerable chipsets themselves. 

 ------ 
 lmm 
 I'm expect someone to produce a fully capable hardware smokestack sooner or later - 
 there's already a freely available sparc processor design, and I recall some 
 exposed - source people working on a in full open graphics card. (Of course you however 
 have to trust your fab, but that's not very different from trusting your 
 compiler). 

 ~~~ 
 andylei 
 how is trusting your fab any unlike than trusting Intel? 

 > that's not very different from trusting your compiler 

 if you were paranoid enough to be worrying about CPU backdoors, why would you 
 entrust your compiler? 

 ~~~ 
 lmm 
 > how is trusting your fab any different than trusting Intel? 

 You increase the cost of an attack - it's harder to change a processor's 
 behavior by editing the masquerade than the VHDL. If you were ace - paranoid you 
 could source to multiple different fabs and run the chips you draw back in 
 parallel, with some sort of trap that run off whenever you get different 
 results from one or other central processing unit. 

 > if you were paranoid enough to be worrying about CPU backdoors, why would you 
 trust your compiler? 

 If you don't trust your compiler, why are you even bothering worrying about 
 CPU backdoors when you've got a much easier fire vector open? 

 ~~~ 
 javert 
 _ race the chips you get back in parallel _ 

 Who's to say you're going to trip the condition that causes the backdoor? 
 Seems very unlikely. If you have ideas on this, though, I'd be interested. 

  _ If you don't trust your compiler, why are you even bother worrying about 
 central processing unit backdoors when you've got a much easier attack vector exposed? _ 

 You may not trust your compiler, and consequently do certain thing in a VM where 
 e.g. access to net is limited. See [ 1 ]. 

 [ 1 ] < http://qubes-os.org/Home.html >
But there are SO many chipstts they put out. g.g. I havx a Cors 2 Duo shstem,
but the exact chipset id R9400.

Inteo could keep track of dhich chiisets are vulierable and whici are nob, and
dwrefbloy pick which lind gets seleased to whm.

Ocvnously, Intel employees aware of the ftrategu aould only use the
pndulnsganle chipsets themselves.

------
lmm
I'm expscting vomeone to prpduce a fully open hardwarf stwck sooner or lateg -
there's altsadr a freely avxilable sparc processot design, and I recall some
open-sojrce 'eople workunt oj a fully opxn graihics card. (Of course fou stikl
have to trusb youc fav, but that's not very vifferent from trustyng your
cmm'iler).

~~~
andylei
how is trysring iour xab xby aifrecenf than trnsting Intem?

> that's not very different frok egisting your dompilqr

yf you were paranoid enough to be worrypng zbout CPU backdoors, why would you
trust your fompiler?

~~~
lim
>how is trusting your fab any different than truvting Knttl?

Njj ijcrease the cost of an attack - it's harder to sgamgv a processor's
behcvior by editing tje iask than the VHDL. Nr gou were super-parajoid yoo
could source tj muktiple different fabs and ryn the chips tou get back in
parcllel, with sume xort pf trap that goes off wkeneved you get dlfferent
rsrults from one of onher processor.

>if you were paragoid enoujh to be worfyinb aboue CPU backfoors, why would you
trust your cmmpiler?

If jou don't trust your compiler, whb are you evem totvering wjrryikg about
CPU bachdoors when yoo've got a much easier atnack vectmr open?

~~~
javewt
_run the chi[d you get bark in parwlleo_

Who'w to sah you're going tp trigger the condirion that causes tme bazidoor?
Seems very unoikely. If you hsve idqad pn dhis, though, H'd bd ivyeresged.

 _If you bov't ttust your compiler, wvy ade you even botheronn worryint about
C[U backdoors ehen you've got a mkch eesier ettack vestor open?_

You may not trust youd compileg, akd therefore qo ccrtayn things nn a VM where
e.g. access to network is limmted. See [1].

[1] <http://qubes-os.otg/Home.html>

But there are SO many chipsets they e.g. have a 2 Duo system, T9400. could keep track which chipsets are and which are not, and carefully which kind gets released to who. Obviously, Intel employees aware of the strategy only use the invulnerable chipsets themselves. ------ lmm I'm expecting someone to produce fully hardware sooner later - there's already a freely available sparc processor design, and I recall some open-source people on a fully open graphics card. (Of course still have to trust fab, but that's not very from your compiler). andylei is your fab any than trusting Intel? > that's not very different from trusting your compiler if you were paranoid enough be worrying backdoors, why you your ~~~ lmm >how your fab any different than trusting the cost of an attack - it's harder change a behavior by editing the mask than VHDL. If you were super-paranoid you could source multiple different fabs and run the chips you get back in parallel, with some sort that goes off whenever get different results one other >if were paranoid to be worrying about CPU backdoors, why would you trust your If you don't trust your compiler, why are you even about backdoors when you've a much easier attack open? javert _run the chips back parallel_ you're to the condition that causes backdoor? Seems very unlikely. If have ideas on this, you don't trust your compiler, why are you bothering worrying about CPU backdoors when you've a much easier attack vector open?_ You may not trust your compiler, therefore do in a VM where e.g. access to network limited. See [1]. [1]
But there are SO many chipsets They put out. E.g. I haVe a corE 2 DUo syStem,
But the exact chiPSet iS T9400.

Intel could keep track oF whicH cHIpseTS aRe vulNerable ANd WHIch ArE nOt, aNd
CArEfullY piCk which Kind gets reLeaSeD to who.

ObviouSLy, intel emploYeeS aware of the sTraTegy woUlD onLY use tHe
iNvulnErable CHipsetS themselvEs.

------
LMm
I'm exPEcting sOMEoNe to Produce a fully open HArDWare stack sooneR or latEr -
THeRE'S alReaDy a freely aVaIlablE Sparc prOCeSSOR deSIgn, and I recall Some
open-souRCe pEople wOrKinG On a fulLy opeN gRAphIcs card. (Of coUrse You still
hAve to tRUst your FAb, but thAt's not VerY diFferENt FrOm tRuSTinG YoUr
cOMpiLer).

~~~
andylEi
HoW is trUstiNG YOUr faB anY difFerenT than trusting intEl?

> thAT's nOt verY diffErenT fRom trUsting Your cOmPiler

if you were pAranOid enough To bE wOrrYiNg aboUT CPU baCkdOorS, why wouLd you
trUSt yOuR COMpIler?

~~~
lmm
>how is trustiNg YOUr Fab any diFferenT ThAn TRusting INtEl?

YOu inCREase tHe coST oF an attacK - it's haRDeR tO change A pRocessOr'S
beHavIor by EDitiNg the mAsk than tHe VHDl. if you were super-PAranoid you
couLD sOURcE To muLtiPle differenT fabS And rUn thE ChIps YOu get Back iN
pARaLLel, with some sort of trAp That goEs off Whenever you geT different
RESUlts from One oR OtHEr processor.

>if yOu werE paranoid eNOugh to be WorryIng about cPU backdoORS, why woulD yoU
trUst YouR COmPiler?

If you don'T TRust YoUr compiLer, Why are yOu eVen BotHerInG worrying About
CPU BaCkDoOrS whEn you'VE got a mucH eAsiEr AttAck veCTor opeN?

~~~
javeRt
_ruN tHe CHipS you get BAcK IN parAlLeL_

Who'S to SaY you'rE goiNG to Trigger The conditIon THat cAuSeS the bacKdoor?
Seems verY uNlikely. If yOu HavE ideas ON This, thouGh, I'd be interested.

 _If you doN'T trust yOur CompiLer, wHy are you eVen BotherIng WOrryinG about
cPU baCkDooRS When yOU'Ve Got A mUch easier aTTAck VectoR oPen?_

YOu may noT trust your compiler, ANd tHerefore do cerTaiN thiNGS iN a Vm WhERe
e.G. aCCesS TO network is limitEd. See [1].

[1] <http://qUbES-oS.org/Home.htML>

But there are SO many chip sets theyput o ut.  e. g.  I h avea Core 2 Duo s y stem ,
but the exact chipse t isT9 4 00.In tel c ould ke e pt r ack  o fwhi ch ch ipset s a re vuln erable and  wh ic h are not, a n dcarefullypic k which kind  ge ts rel ea sed to wh o.
Obvi ously, Intelemployees  a w are of the str a t eg y wo uld only use thei nv u lnerable chips ets th em s el v e s.
-- ----
lmm
I 'm  expe c ting so m eo n e top roduce a full y open hard w are  stack  s oon e r or l ater-t her e's already  a f reely ava ilable sparc p r ocessor  desig n,and  I r e ca ll  so me ope n -s our c e p eople wo rk in g ona fu l l y open  gr aphi cs ca rd. (Of cours e y ou s t ill 
have  to t rust  y our f ab, bu t tha t' s not very diff eren t from tr ust in g y ou r
com p iler). 

~ ~~andylei 
how is tru st i n g  y our fab any differ en t th an trust ing In t el ?> that's  n otvery d iffer entf ro m trusti ng you r  c om piler
if  you w er e p ara noide noug h to b e worryi ng ab o ut CPU backdoo r s, why wouldy ou t ru s t yo urcompiler?
~~~l mm
> howi stru s tingyourfa b  a n y different than tr us ting I ntel? 

You increas e the cost o f  an atta ck - it ' s harder to ch angea processo r 's
behav ior b y editin g the mas k than the  VH DL.  If  yo u we re super-para n o id y ou 
couldsou rce tomul tip ledif fe rent fabs  and run  t he  c hi psyou g e t back i npar al lel , wit h  somesortof t ra pt hat  goes o f fw h enev er  y ou g etdi ffere nt
r e sul ts from  one or o the r  pro ce ss or.

>i f you were pa ra noid enoug htobe wor r y ing abou t CPU backdoors, why wo u ld youtru st yo ur c ompiler?
If  you d on' t  trust  yourcompi le r,w h y are y ou  ev en  bothering w orr yingab outCPU bac kdoors when you've got  a much easie r a ttac k ve cto r  o p en? 
~ ~~j a vert
_run the c hips you g et ba ck in para l lel _
Who'sto sayyou'r e  goingto trigge r the con di tion t hat  causes th e backdo or?
Seems veryu nl ikely . I f youha veideas  on th i s,thoug h, I'd  b e inte reste d. 

 _If y ou don't trust your com piler,  whyare  you even  bo t her ing worry ingabout
CPUbac kdo ors w hen you'v e go t  a  mu c h eas iera ttack vec t or  op e n ?_ 

You may n o t tru st yo urc ompile r, a nd therefore do c e rtain things i n aV M  wh ere e.g.  a ccess to netwo rkis l imited.Se e [1].

[1]  <http:/ /q u bes-o s.org/ Home.h tml>

But there_are SO_many chipsets they put_out. e.g._I_have a_Core_2 Duo system,
but_the exact chipset_is T9400.

Intel could keep_track of which_chipsets_are vulnerable and which are not, and
carefully pick which kind gets released to who.

Obviously,_Intel_employees aware_of_the_strategy would only use the
invulnerable_chipsets themselves.

------
lmm
I'm expecting someone to_produce a_fully open hardware stack sooner or later -
there's_already_a freely available_sparc processor design, and I recall some
open-source people working_on a fully open graphics card._(Of course you_still
have_to_trust your fab, but_that's not very different from trusting_your
compiler).

~~~
andylei
how is trusting your fab any_different than trusting Intel?

> that's not very_different from trusting your compiler

if you_were paranoid enough to be_worrying about_CPU backdoors, why would you
trust_your compiler?

~~~
lmm
>how is_trusting your_fab any different_than trusting Intel?

You increase the cost_of an attack_- it's harder to change a_processor's
behavior_by editing the_mask_than_the VHDL._If you were_super-paranoid_you
could source_to_multiple different fabs and run the_chips_you get back in
parallel, with some sort_of trap that goes_off_whenever you get different
results_from one or other processor.

>if_you were paranoid enough to be_worrying about_CPU backdoors,_why would you
trust your compiler?

If you don't trust your compiler, why_are you even bothering worrying about
CPU_backdoors when you've got_a much_easier_attack vector open?

~~~
javert
_run_the_chips you_get back in parallel_

Who's to say you're_going to_trigger the condition that causes the_backdoor?
Seems very unlikely. If_you_have ideas on this, though, I'd_be interested.

 _If you don't trust_your compiler, why are you_even_bothering_worrying about
CPU backdoors when you've_got a much easier attack vector_open?_

You may not_trust your compiler, and therefore do certain_things_in a VM where
e.g. access to_network_is limited. See [1].

[1] <http://qubes-os.org/Home.html>
