ilebedev

Verifying that +ilebedev is my blockchain ID. https://onename.com/ilebedev

ilebedev

Keybase proof

I hereby claim:

• I am ilebedev on github.
• I am ilebedev (https://keybase.io/ilebedev) on keybase.
• I have a public key whose fingerprint is FBB1 47B8 4A9D B133 B734 37AC 7486 5BBD ACFE 0D53

To claim this, I am signing this object:

ilebedev

in a little more detail: The enclave loads something, and expects an honest reply. a



Assume the enclave has guarantees of privacy and integrity, and is not denied service.
Assume the OS is dishonest, but will respond to the Enclave's requests (but can lie).

The *OS* stores an array of `N` data blocks `X = {x_i for i in Z_N} = x_0, x_1, ... x_{N-1}`.
Over this array, the *OS* has computed a merkel tree `T` with N leaves, where the leaves are hashes of the elements of `X`.

ilebedev

// root_of_trust.c
#include "sha3/sha3.h"

/* The location and size of the bootloader in DRAM
are linked into the boot ROM image. */
extern const void * bootloader_ptr;
extern const size_t bootloader_size;

/* the expected SHA-3-512 hash is also a constant
linked into the boot ROM image */

ilebedev

# root_of_trust.S
.global reset_vector
  reset_vector:
  # ( all but hart 0 stall and wait for an interrupt. # Hart 0 proceeds, and will wake other harts if it boots. )
  csrr a0, mhartid
  bne a0, zero, .other_hart

  # Prepare a C execution environment
  la sp, m_stack_ptr

ilebedev

// Add at line XXX:XXX

/* TODO: replace this with a constant encoding 
    the manufacturer's public key: */
uint_t pk_m[32] = {\xDE, \xAD, \xBE, \xEF, ...};

extern uint8_t boot_image_certificate[64];

// Add at line XXX:XXX
if (!verify signature of hash with pk_m) {

ilebedev

// Add at line XXX:XXX

// TODO: populate these constants via a linker script
extern uint8_t pk_m[32];
extern uint8_t pk_vendor[32];
extern uint8_t boot_image_certificate[64];
extern uint8_t boot_image_certificate[64];

// Add at line XXX:XXX
if (!verify signature of hash with pk_m) {

ilebedev

// Add at line XXX:XXX

// TODO: populate this constant via a linker script
extern uint8_t known_good_hash[64];

// Add at line XXX:XXX
for (unsigned int i=0; i<8; i++) {
  if ((uint64_t)known_good_hash)[i] != (uint64_t)hash)[i]) {
    // Panic
    // TODO: print an error

ilebedev

uint8_t secret_entropy[64];
uint8_t pk[32];
uint8_t sk[64];

#include <ed25519/ed25519.h>

/* This seed is as valuable as the secret key,
   so make sure it comes from a trustworthy source
   and will remian private. */
// Read/generate the secret seed from which keys are created

ilebedev

#include <ed25519/ed25519.h>

uint8_t pk[32];
uint8_t sk[64];

/* This seed is as valuable as the secret key! */
uint8_t secret_entropy[64];

/* NOTE: we assume some application-dependent source of trusted entropy */
get_trusted_entropy(secret_entropy, 64);