As far as a 'brain' goes, though, it still doesn't account for consciousness
A neat hypothesis. Have any evidence to support it?
There's quite a bit of evidence to support (though I'll readily admit not conclusively) that you're quite wrong.
Integral Calculus isn't "tangible", but the human brain can store information about it in tangible constructs. Likewise, my bank balance. But the storage isn't the actuality, and the bank account information in my brain is no more the actual account than the bank account information on my hard drive is, even though that is likewise represented in tangible and measurable form.
But your bank account has *0* effect on anything outside that which we give it. So this entire line of reasoning is entirely non-sequitur. Your bank account is the tool, not the actor.
Your bank account is not an intangible effect, as you've attempted to define it.
I don't posit self-aware Quantum mechanics and I have no idea how you drew such a wild conclusion, You seem to take a delight with confusing the levers with the driver.
Perhaps I mistook you. You posited that the brain could be the engine that something less tangible *uses*, and then gave QM as an example of an intangible effect. To which I replied, at best, QM provides a source of random input- which is *not* "Free Will". I made the apparently incorrect assumption that if it's not random input that it offers, then you must be claiming it imparts its will upon the engine that is our brain. I'd love to hear your alternative explanation, for the sake of correcting my understanding of your position.
And how, pray tell can a neural network "see" what's at the controls of a bulldozer if the driver no more visible to man or computer than cosmic rays were to the Babylonians?
The same way the babylonians (or more specifically, their progeny) eventually did. By expanding their knowledge through observation. Our neural network allows for this. So do artificial ones.
On top of which you seem to be assuming that we have neural networks that can accurately conduct a Turing Test. As I recall, the original test specifically required a human as the test instrument/reference.
We do have neural networks that can accurately conduct a Turing Test. There's one driving your fingers right this minute.
I make no assumption that artifical networks that to date have only just now come within 3 orders of magnitude of the complexity of the Neural Network the Turing Test uses as a benchmark. That assumption was all you. I don't think anybody said "there we are, we've got it!"
The electro-chemical signals flowing through the complex network of your brain are quite tangible. You can track them with physical probes, you can track them with radiation scanners, you can track them with passive external monitors.
Then everything in this universe that man has any knowledge of that isn't fantasy is tangible. I'm glad we cleared that up.
"Spiritual" could be one theory, but why be so limited in your philosophy, Horatio? We have perfectly respectable scientists arguing for rolled-up micro-dimensions. We have quantum mechanics doing spooky things - and just maybe doing them at a macro scale in biological systems if a recent article I read is on the right track.
QM is a lot of nifty things. A claim that QM effects are somehow sentient, or possess will... well, that's not argued by anyone anywhere that I've ever seen.
QE effects "bubbling" up at a macro scale simply provides more random input to the state machine. It's still a tangible effect, by your very own definition.
One thing I've learned about science is that it's never "done". We get finer and finer approximations until it all seems to boil into fuzz. Then we try something different and maybe learn something new.
No, science is never done, but there are mountains of evidence on all the hills that are arguments around yours, but not a single shred of evidence on yours. Could that change some day? Yes. I concede that. But I'm no more inclined to look for a spiritual cause for consciousness than I am to look for marks of a sky fairy having created this planet.
If my world-view was all metal and lubricants, would I see the human in the seat of the bulldozer? Or be able to tell it from a ghost? A computer? An orang-utan?
Why couldn't you?
A computer certainly can. Using very simplified versions of our very own wetware- neural networks.
Of course not, but that in no way implies that a non-deterministic universe is either.
Free will is a pretty abstract concept, and like it or not, the brain is nothing more than a really big state machine.
We could argue all day whether or not the resulting properties of that state machine given the billion of essentially random inputs it experiences evert second constitutes a free will, or simply an emergent quality, but in no way is the position that "Free Will is an illusion" (That I hold) tied to the belief that the universe is deterministic as you tried say.
No, I don't think you really had an actual choice as to whether you got out of bed. You were following a set of state calculations running through a piece of hardware more complicated than anything man is aware of in the universe. That doesn't mean the universe is deterministic. Just that your brain is.
Wait- you really think decisions don't start before you're consciously aware of them? You really think you've got a little soul hiding in that bucket of conductive soup in your cranium working the controls like the little alien in Men In Black?
Fascinating. Neuro-"Scientists" indeed.
I think the illusion of free will is simply a misunderstanding of how complex the feedback loops and source information really are.
We like to simplify a choice that involves billions of neuronal inputs over the spatial and time domains as "I chose X over Y, freely."
It's simple-mindedness, and an insult to the complexity of the neural network running our consciousness.
Is it? Or is the brain just the engine that something less tangible uses?
The electro-chemical signals flowing through the complex network of my brain are quite intangible.
If you're trying to imply something spiritual, which I suspect you are, then let me ask you this: What reason do you have to even suspect such a thing?
What makes you think that a neural network as complicated as the brain can't pass the Turing Test? Particularly to people running on roughly equivalent machines?
Your question is interesting, but ultimately I think right up there with infinite universes theories.
The science isn't in yet.
You understand it's so very frustrating when you say this, right? No, the science is not in on your by-all-definitions implausible hypothesis. Nor will it ever be, because it cannot be, nor is there any evidence to even suggest that it should be.
Yeah, right. Why didn't anybody else build a plane than has the capability of ascending into orbit as needed and come back then ? Perhaps because the enormous energy needed to go from aerodynamic flight speed to orbital velocity can't simply be carried along in a pod or something ?
You're right... However, a significant suborbital fraction of orbital velocity is achievable with current cutting-edge-not-quite-functional technology, without massive tanks of oxidizer. I'm pretty certain their claim of 2020 for this being possible to them is a complete joke, and even if they could get the thing into a significant fraction of orbital velocity quiet enough not to be noticed... It sure as hell wouldn't be going home after.
Re-entry isn't early warning. ICBM launch is early warning. By the time you see the plasma trail of reentry, your options are just about gone.
This is a fantastic first-strike weapon, in that it can be done with precisely no warning.
As for disabling second-strike capability? Na. This is just the Russians freaking out that THAAD/Aegis systems may be getting deployed around enough sensitive spots that they feel even their first strike capability is becoming limited. A plane boosting slowly into orbit can do so without being noticed. An ICBM cannot.
An Aegis can't hit a terminal ICBM RV unless it has warning. With something that can achieve orbit, or even suborbital velocity slow enough to not be noticed can de-orbit payloads that will absolutely not be noticed until far enough through re-entry as to be impossible to intercept with THAAD batteries.
One does not fire something straight down with 15,000mph of orbital velocity. there's no RV in existence that would survive such a maneuver. You have to hit the 15,000mph winds head on, which means *not* straight down. No matter what, your only way back in is ballistic. The only advantage this really has, is that you may potentially be able to get it into orbit without getting caught, which takes away the biggest early-warning to a hostile party that you're about to nuke them- the launch. With no early warning, a THAAD/Aegis, any terminal interceptor will likely not have enough warning to respond. The space bomber is the easy answer to terminal-stage interception. It carries the drawback of being very easy to shoot down, but likely not before it has de-orbited its payload. So, easy to take out in a first strike (making it a useless second-strike weapon), but also pretty much impossible to stop a first trike from the vehicle. This is an unwise escalation in nuclear armament. I thought we had treaties preventing this nonsense. It's a space Red October.
Legally, not true. Literally, they certainly sound similar, but gross negligence has a very specific (non) meaning in law.
It's basically up to every step in the chain from investigation, through charging, through indictment, through prosecution to determine that they were or were not (often quite subjectively) "beyond" careless.
I don't think she was in this case. Stupid, yes. Criminally? Na.
If she were a regular employee of somewhere, sure, she'd lose her job. Maybe even get some probation. But she was the Secretary of State. Like it or not, there is definitely a higher barrier to prosecuting her for the way she handled State business than joe schmoe down in Accounting. This is actually a regular concept in *most* democracies.
Would we know? I don't remember Congress engaging in a witch hunt against them.... Serious question.
We dredged through 30k+ emails to find what, 100 violations that weren't even enough to warrant a recommendation to prosecute? (And come on, if it was some seriously classified shit, the parties responsible for that decision are not going to throw their lives and careers into the fire just to cover her ass)
You sure it wasn't simply a NYTimes article that passed through the wrong set of hands and ended up being Classified as due course?
I like to believe that if they found evidence of some seriously negligent wrong-doing, they would have recommended to charge her. Especially given the publicity.
Being she is running for the office of president, and cannot be precluded from holding security clearance by virtue of winning that office, should she win, you are hereby cordially invited to submit your vote to fire her, or make sure she doesn't hold security clearance in the following administrations.
Seriously, wtf do you want? She fudged up some confidential documents. It's not like she sold a fucking war to congress on quite-literally-fabricated information.
I'd love it if we started holding the government accountable for all the acts of SOP that are violations of the law, particularly with the trend that the last president set.
But tell me this, we're applying it now, to this level of furor, over so small a thing, why? Am I truly to believe you don't have an ulterior motive?
Valerie Plame. Judith Miller. Read and learn.
You know exactly what the White House told those congresscritters. If I didn't know shit and I had trusted the intelligence guys in front of me who were feeding them comically bad information that they knew was such, I'd have voted for it. You would have too.
Were you being purposefully disingenuous, or do you really not know how the war was sold?
If I had mod points, I think I'd use them to mod you funny. The transparency of your desperate grasping for something that sticks really is a kind of gallows humor.
I mean, let's be real... I don't support the woman. (does anyone really, or have we all just agreed that we're *not* going to fucking elect Trump?) but you're trying to burn her at the stake for shit that is SOP at that level of government. Is that a problem? Ya, you betcha (I suspect that reminds you of someone you adore)
Are we to burn a woman at the stake running for the highest office of the land for committing SOP?
To what end? So that your candidate can win? (because if your candidate isn't her, for better or for worse, they're not going to)
You guys are Clintoning another Clinton. You're going to dig, and you're going to dig, until you find *something* that fits the qualification of high crime or misdemeanor. Seriously, wtf *is* your actual problem? Be honest, nobody knows who you are in real life.
Perhaps you do need to read the reference? You don't seem to be as familiar with the boot process as you think.
No, I really don't. Because I helped author literature that describes the process, as I was writing software to decrypt, and dump the symbol tables in the kernel.
For your reference, here's the iOS IMG3 boot-chain container structure:
typedef struct img3File {
uint32_t magic;// ASCII_LE("Img3")
uint32_t fullSize;// full size of fw image
uint32_t sizeNoPack;// size of fw image without header
uint32_t sigCheckArea;// although that is just my name for it, this is the // size of the start of the data section (the code) up to // the start of the RSA signature (SHSH section)
uint32_t ident;// identifier of image, used when bootrom is parsing images // list to find LLB (illb), LLB parsing it to find iBoot (ibot), // etc.
img3Tag tags[];// continues until end of file
};
typedef struct img3Tag {
uint32_t magic;// see below
uint32_t totalLength;// length of tag including "magic" and these two length values
uint32_t dataLength;// length of tag data
uint8_t data[dataLength];
uint8_t pad[totalLength - dataLength - 12];// Typically padded to 4 byte multiple
};
VERS: iBoot version of the image
SEPO: Security Epoch
SDOM: Security Domain
PROD: Production Mode
CHIP: Chip to be used with. example: 0x8900 for S5L8900.
BORD: Board to be used with
KBAG: Contains the IV and key required to decrypt; encrypted with the GID Key
SHSH: RSA encrypted SHA1 hash of the file
CERT: Certificate
ECID: Exclusive Chip ID unique to every device
TYPE: Type of image, should contain the same string as the header's ident
DATA: Real content of the file
KBAG is the symmetric key (protected by hardware AES engine- but that's useless if someone already has arbitrary code execution on the device [the main reason they stopped using I suspect.])
SHSH is the asymmetric signature to ensure that it won't boot something that *has* been modified.
It has been this way since forever. it is still this way now.
Whether or not the reference completely outlines the boot process as (we) security researchers know it is not relevant to our understanding of it.
Every single stage of the boot process is protected under this scheme. A symmetric key/IV encrypted by the hardware GID key to obfuscate it, which in turn obfuscates the kernel, and an SHA signature encrypted asymmetrically with RSA to make it tamper-proof.
TFA is about them no longer bothering with the symmetric encryption on the kernel portion. (The boot stages before that are still encrypted).
AES is (well, was prior to most recent beta referenced in TFA) in fact used.
I need not read the reference, as I'm intimately familiar with the boot process.
My guess is that you read "signature" in there and something about a cert, and assumed that actually applied to the encryption used on the kernel binary itself rather than the signature for it.
A signature must necessarily be asymmetric so that someone can decrypt it without being able to encrypt a new signature.
This concept exists in regular SSL as well. One need not encrypt an entire certificate with trusted information in it, only the signature.
The kernel is *still* protected by the asymmetrically encrypted signature in the new versions of iOS, it simply isn't encrypted anymore.
That is to say, the KBAG field (containing the AES GID encrypted AES KEY/IV for the kernel) of the kernel header is now blank.
The OP was referring to the fact that the symmetric encryption did nothing to help things, it was always the asymmetric encrypted signature that did the real protection.
AES is symmetrical.
The kernelcache is encrypted using AES.
You're describing a hash collision on a signature. You're ignorant of the topic being discussed, please stop posting with such a confident posture.
It's actually Apple that uses the nonstandard term... I had never heard of a kernel referred to as a "kernel cache" before I started hacking iOS back in ye olden days.
Slashdot Mirror
As far as a 'brain' goes, though, it still doesn't account for consciousness
A neat hypothesis. Have any evidence to support it?
There's quite a bit of evidence to support (though I'll readily admit not conclusively) that you're quite wrong.
The data isn't the hard part. Getting the base layout is.
A baby's brain isn't an amorphous soup of neurons.
Integral Calculus isn't "tangible", but the human brain can store information about it in tangible constructs. Likewise, my bank balance. But the storage isn't the actuality, and the bank account information in my brain is no more the actual account than the bank account information on my hard drive is, even though that is likewise represented in tangible and measurable form.
But your bank account has *0* effect on anything outside that which we give it. So this entire line of reasoning is entirely non-sequitur. Your bank account is the tool, not the actor.
Your bank account is not an intangible effect, as you've attempted to define it.
I don't posit self-aware Quantum mechanics and I have no idea how you drew such a wild conclusion, You seem to take a delight with confusing the levers with the driver.
Perhaps I mistook you. You posited that the brain could be the engine that something less tangible *uses*, and then gave QM as an example of an intangible effect. To which I replied, at best, QM provides a source of random input- which is *not* "Free Will". I made the apparently incorrect assumption that if it's not random input that it offers, then you must be claiming it imparts its will upon the engine that is our brain. I'd love to hear your alternative explanation, for the sake of correcting my understanding of your position.
And how, pray tell can a neural network "see" what's at the controls of a bulldozer if the driver no more visible to man or computer than cosmic rays were to the Babylonians?
The same way the babylonians (or more specifically, their progeny) eventually did. By expanding their knowledge through observation. Our neural network allows for this. So do artificial ones.
On top of which you seem to be assuming that we have neural networks that can accurately conduct a Turing Test. As I recall, the original test specifically required a human as the test instrument/reference.
We do have neural networks that can accurately conduct a Turing Test. There's one driving your fingers right this minute. I make no assumption that artifical networks that to date have only just now come within 3 orders of magnitude of the complexity of the Neural Network the Turing Test uses as a benchmark. That assumption was all you. I don't think anybody said "there we are, we've got it!"
The electro-chemical signals flowing through the complex network of your brain are quite tangible. You can track them with physical probes, you can track them with radiation scanners, you can track them with passive external monitors.
Then everything in this universe that man has any knowledge of that isn't fantasy is tangible. I'm glad we cleared that up.
"Spiritual" could be one theory, but why be so limited in your philosophy, Horatio? We have perfectly respectable scientists arguing for rolled-up micro-dimensions. We have quantum mechanics doing spooky things - and just maybe doing them at a macro scale in biological systems if a recent article I read is on the right track.
QM is a lot of nifty things. A claim that QM effects are somehow sentient, or possess will... well, that's not argued by anyone anywhere that I've ever seen. QE effects "bubbling" up at a macro scale simply provides more random input to the state machine. It's still a tangible effect, by your very own definition.
One thing I've learned about science is that it's never "done". We get finer and finer approximations until it all seems to boil into fuzz. Then we try something different and maybe learn something new.
No, science is never done, but there are mountains of evidence on all the hills that are arguments around yours, but not a single shred of evidence on yours. Could that change some day? Yes. I concede that. But I'm no more inclined to look for a spiritual cause for consciousness than I am to look for marks of a sky fairy having created this planet.
If my world-view was all metal and lubricants, would I see the human in the seat of the bulldozer? Or be able to tell it from a ghost? A computer? An orang-utan?
Why couldn't you?
A computer certainly can. Using very simplified versions of our very own wetware- neural networks.
Of course not, but that in no way implies that a non-deterministic universe is either.
Free will is a pretty abstract concept, and like it or not, the brain is nothing more than a really big state machine.
We could argue all day whether or not the resulting properties of that state machine given the billion of essentially random inputs it experiences evert second constitutes a free will, or simply an emergent quality, but in no way is the position that "Free Will is an illusion" (That I hold) tied to the belief that the universe is deterministic as you tried say.
No, I don't think you really had an actual choice as to whether you got out of bed. You were following a set of state calculations running through a piece of hardware more complicated than anything man is aware of in the universe. That doesn't mean the universe is deterministic. Just that your brain is.
Wait- you really think decisions don't start before you're consciously aware of them? You really think you've got a little soul hiding in that bucket of conductive soup in your cranium working the controls like the little alien in Men In Black?
Fascinating. Neuro-"Scientists" indeed.
Don't conflate free-will-is-an-illusion with determinism. They're unrelated. Shame on you.
That wasn't a strawman, it was a legitimate question coupled with an unimpeachable assertion coupled with his feelings on the matter.
A legitimate question that you, my friend, completely failed to answer.
I think the illusion of free will is simply a misunderstanding of how complex the feedback loops and source information really are.
We like to simplify a choice that involves billions of neuronal inputs over the spatial and time domains as "I chose X over Y, freely."
It's simple-mindedness, and an insult to the complexity of the neural network running our consciousness.
Is it? Or is the brain just the engine that something less tangible uses?
The electro-chemical signals flowing through the complex network of my brain are quite intangible.
If you're trying to imply something spiritual, which I suspect you are, then let me ask you this: What reason do you have to even suspect such a thing?
What makes you think that a neural network as complicated as the brain can't pass the Turing Test? Particularly to people running on roughly equivalent machines?
Your question is interesting, but ultimately I think right up there with infinite universes theories.
The science isn't in yet.
You understand it's so very frustrating when you say this, right? No, the science is not in on your by-all-definitions implausible hypothesis. Nor will it ever be, because it cannot be, nor is there any evidence to even suggest that it should be.
Because geosynchronous orbits are 22,000 miles plus in altitude. There's no conceivable way to get there without a really big rocket.
Yeah, right. Why didn't anybody else build a plane than has the capability of ascending into orbit as needed and come back then ? Perhaps because the enormous energy needed to go from aerodynamic flight speed to orbital velocity can't simply be carried along in a pod or something ?
You're right... However, a significant suborbital fraction of orbital velocity is achievable with current cutting-edge-not-quite-functional technology, without massive tanks of oxidizer. I'm pretty certain their claim of 2020 for this being possible to them is a complete joke, and even if they could get the thing into a significant fraction of orbital velocity quiet enough not to be noticed... It sure as hell wouldn't be going home after.
Re-entry isn't early warning. ICBM launch is early warning. By the time you see the plasma trail of reentry, your options are just about gone. This is a fantastic first-strike weapon, in that it can be done with precisely no warning. As for disabling second-strike capability? Na. This is just the Russians freaking out that THAAD/Aegis systems may be getting deployed around enough sensitive spots that they feel even their first strike capability is becoming limited. A plane boosting slowly into orbit can do so without being noticed. An ICBM cannot. An Aegis can't hit a terminal ICBM RV unless it has warning. With something that can achieve orbit, or even suborbital velocity slow enough to not be noticed can de-orbit payloads that will absolutely not be noticed until far enough through re-entry as to be impossible to intercept with THAAD batteries.
One does not fire something straight down with 15,000mph of orbital velocity. there's no RV in existence that would survive such a maneuver. You have to hit the 15,000mph winds head on, which means *not* straight down. No matter what, your only way back in is ballistic. The only advantage this really has, is that you may potentially be able to get it into orbit without getting caught, which takes away the biggest early-warning to a hostile party that you're about to nuke them- the launch. With no early warning, a THAAD/Aegis, any terminal interceptor will likely not have enough warning to respond. The space bomber is the easy answer to terminal-stage interception. It carries the drawback of being very easy to shoot down, but likely not before it has de-orbited its payload. So, easy to take out in a first strike (making it a useless second-strike weapon), but also pretty much impossible to stop a first trike from the vehicle. This is an unwise escalation in nuclear armament. I thought we had treaties preventing this nonsense. It's a space Red October.
Extremely careless == gross negligence.
Legally, not true. Literally, they certainly sound similar, but gross negligence has a very specific (non) meaning in law.
It's basically up to every step in the chain from investigation, through charging, through indictment, through prosecution to determine that they were or were not (often quite subjectively) "beyond" careless.
I don't think she was in this case. Stupid, yes. Criminally? Na.
If she were a regular employee of somewhere, sure, she'd lose her job. Maybe even get some probation. But she was the Secretary of State. Like it or not, there is definitely a higher barrier to prosecuting her for the way she handled State business than joe schmoe down in Accounting. This is actually a regular concept in *most* democracies.
Would we know? I don't remember Congress engaging in a witch hunt against them.... Serious question. We dredged through 30k+ emails to find what, 100 violations that weren't even enough to warrant a recommendation to prosecute? (And come on, if it was some seriously classified shit, the parties responsible for that decision are not going to throw their lives and careers into the fire just to cover her ass)
You sure it wasn't simply a NYTimes article that passed through the wrong set of hands and ended up being Classified as due course?
I like to believe that if they found evidence of some seriously negligent wrong-doing, they would have recommended to charge her. Especially given the publicity.
Being she is running for the office of president, and cannot be precluded from holding security clearance by virtue of winning that office, should she win, you are hereby cordially invited to submit your vote to fire her, or make sure she doesn't hold security clearance in the following administrations.
Seriously, wtf do you want? She fudged up some confidential documents. It's not like she sold a fucking war to congress on quite-literally-fabricated information.
I'd love it if we started holding the government accountable for all the acts of SOP that are violations of the law, particularly with the trend that the last president set.
But tell me this, we're applying it now, to this level of furor, over so small a thing, why? Am I truly to believe you don't have an ulterior motive?
Valerie Plame. Judith Miller. Read and learn.
You know exactly what the White House told those congresscritters. If I didn't know shit and I had trusted the intelligence guys in front of me who were feeding them comically bad information that they knew was such, I'd have voted for it. You would have too.
Were you being purposefully disingenuous, or do you really not know how the war was sold?
If I had mod points, I think I'd use them to mod you funny. The transparency of your desperate grasping for something that sticks really is a kind of gallows humor.
I mean, let's be real... I don't support the woman. (does anyone really, or have we all just agreed that we're *not* going to fucking elect Trump?) but you're trying to burn her at the stake for shit that is SOP at that level of government. Is that a problem? Ya, you betcha (I suspect that reminds you of someone you adore)
Are we to burn a woman at the stake running for the highest office of the land for committing SOP?
To what end? So that your candidate can win? (because if your candidate isn't her, for better or for worse, they're not going to)
You guys are Clintoning another Clinton. You're going to dig, and you're going to dig, until you find *something* that fits the qualification of high crime or misdemeanor. Seriously, wtf *is* your actual problem? Be honest, nobody knows who you are in real life.
I draw the line at littering.
Well spoken, sir.
Perhaps you do need to read the reference? You don't seem to be as familiar with the boot process as you think.
No, I really don't. Because I helped author literature that describes the process, as I was writing software to decrypt, and dump the symbol tables in the kernel. For your reference, here's the iOS IMG3 boot-chain container structure: // ASCII_LE("Img3") // full size of fw image // size of fw image without header
// size of the start of the data section (the code) up to
// the start of the RSA signature (SHSH section) // identifier of image, used when bootrom is parsing images
// list to find LLB (illb), LLB parsing it to find iBoot (ibot),
// etc. // continues until end of file
// see below // length of tag including "magic" and these two length values // length of tag data // Typically padded to 4 byte multiple
typedef struct img3File {
uint32_t magic;
uint32_t fullSize;
uint32_t sizeNoPack;
uint32_t sigCheckArea;// although that is just my name for it, this is the
uint32_t ident;
img3Tag tags[];
};
typedef struct img3Tag {
uint32_t magic;
uint32_t totalLength;
uint32_t dataLength;
uint8_t data[dataLength];
uint8_t pad[totalLength - dataLength - 12];
};
VERS: iBoot version of the image
SEPO: Security Epoch
SDOM: Security Domain
PROD: Production Mode
CHIP: Chip to be used with. example: 0x8900 for S5L8900.
BORD: Board to be used with
KBAG: Contains the IV and key required to decrypt; encrypted with the GID Key
SHSH: RSA encrypted SHA1 hash of the file
CERT: Certificate
ECID: Exclusive Chip ID unique to every device
TYPE: Type of image, should contain the same string as the header's ident
DATA: Real content of the file
KBAG is the symmetric key (protected by hardware AES engine- but that's useless if someone already has arbitrary code execution on the device [the main reason they stopped using I suspect.])
SHSH is the asymmetric signature to ensure that it won't boot something that *has* been modified.
It has been this way since forever. it is still this way now.
Whether or not the reference completely outlines the boot process as (we) security researchers know it is not relevant to our understanding of it.
Every single stage of the boot process is protected under this scheme. A symmetric key/IV encrypted by the hardware GID key to obfuscate it, which in turn obfuscates the kernel, and an SHA signature encrypted asymmetrically with RSA to make it tamper-proof.
TFA is about them no longer bothering with the symmetric encryption on the kernel portion. (The boot stages before that are still encrypted).
AES is (well, was prior to most recent beta referenced in TFA) in fact used.
I need not read the reference, as I'm intimately familiar with the boot process.
My guess is that you read "signature" in there and something about a cert, and assumed that actually applied to the encryption used on the kernel binary itself rather than the signature for it.
A signature must necessarily be asymmetric so that someone can decrypt it without being able to encrypt a new signature.
This concept exists in regular SSL as well. One need not encrypt an entire certificate with trusted information in it, only the signature.
The kernel is *still* protected by the asymmetrically encrypted signature in the new versions of iOS, it simply isn't encrypted anymore.
That is to say, the KBAG field (containing the AES GID encrypted AES KEY/IV for the kernel) of the kernel header is now blank.
The OP was referring to the fact that the symmetric encryption did nothing to help things, it was always the asymmetric encrypted signature that did the real protection.
AES is symmetrical. The kernelcache is encrypted using AES. You're describing a hash collision on a signature. You're ignorant of the topic being discussed, please stop posting with such a confident posture.
It's actually Apple that uses the nonstandard term... I had never heard of a kernel referred to as a "kernel cache" before I started hacking iOS back in ye olden days.