Atmosphere/exosphere/program/source/boot/secmon_boot_setup.cpp
2020-11-15 08:35:57 -08:00

423 lines
19 KiB
C++

/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <exosphere.hpp>
#include "secmon_boot.hpp"
#include "secmon_boot_cache.hpp"
#include "../secmon_setup.hpp"
#include "../secmon_key_storage.hpp"
namespace ams::secmon::boot {
namespace {
void ValidateSystemCounters() {
const uintptr_t sysctr0 = MemoryRegionVirtualDeviceSysCtr0.GetAddress();
/* Validate the system counter frequency is as expected. */
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_CNTFID0) == 19'200'000u);
/* Validate the system counters are as expected. */
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 0)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 1)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 2)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 3)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 4)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 5)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 6)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 7)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 8)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID( 9)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID(10)) == 0);
AMS_ABORT_UNLESS(reg::Read(sysctr0 + SYSCTR0_COUNTERID(11)) == 0);
}
void SetupPmcRegisters() {
const auto pmc = MemoryRegionVirtualDevicePmc.GetAddress();
/* Set the physical address of the warmboot binary to scratch 1. */
if (GetSocType() == fuse::SocType_Mariko) {
reg::Write(pmc + APBDEV_PMC_SECURE_SCRATCH119, static_cast<u32>(MemoryRegionPhysicalDramSecureDataStoreWarmbootFirmware.GetAddress()));
} else /* if (GetSocType() == fuse::SocType_Erista) */ {
reg::Write(pmc + APBDEV_PMC_SCRATCH1, static_cast<u32>(MemoryRegionPhysicalDramSecureDataStoreWarmbootFirmware.GetAddress()));
}
/* Configure logging by setting bits 18-19 of scratch 20. */
reg::ReadWrite(pmc + APBDEV_PMC_SCRATCH20, REG_BITS_VALUE(18, 2, 0));
/* Clear the wdt reset flag. */
reg::ReadWrite(pmc + APBDEV_PMC_SCRATCH190, REG_BITS_VALUE(0, 1, 0));
/* Configure warmboot to set Set FUSE_PRIVATEKEYDISABLE to KEY_INVISIBLE. */
reg::ReadWrite(pmc + APBDEV_PMC_SECURE_SCRATCH21, REG_BITS_VALUE(4, 1, 1));
/* Write the warmboot key. */
/* TODO: This is necessary for mariko. We should decide how to handle this. */
/* In particular, mariko will need to support loading older-than-expected warmboot firmware. */
/* We could hash the warmboot firmware and use a lookup table, or require bootloader to provide */
/* The warmboot key as a parameter. The latter is a better solution, but it would be nice to take */
/* care of it here. Perhaps we should read the number of anti-downgrade fuses burnt, and translate that */
/* to the warmboot key? To be decided during the process of implementing ams-on-mariko support. */
reg::Write(pmc + APBDEV_PMC_SECURE_SCRATCH32, 0x129);
}
/* This function derives the master kek and device keys using the tsec root key. */
void DeriveMasterKekAndDeviceKeyErista(bool is_prod) {
/* NOTE: Exosphere does not use this in practice, and expects the bootloader to set up keys already. */
/* NOTE: This function is currently not implemented. If implemented, it will only be a reference implementation. */
if constexpr (false) {
/* TODO: Consider implementing this as a reference. */
}
AMS_UNUSED(is_prod);
}
void DeriveMasterKekAndDeviceKeyMariko(bool is_prod) {
/* Clear all keyslots other than KEK and SBK in SE1. */
for (int i = 0; i < pkg1::AesKeySlot_Count; ++i) {
if (i != pkg1::AesKeySlot_MarikoKek && i != pkg1::AesKeySlot_SecureBoot) {
se::ClearAesKeySlot(i);
}
}
/* Clear all keyslots in SE2. */
for (int i = 0; i < pkg1::AesKeySlot_Count; ++i) {
se::ClearAesKeySlot2(i);
}
/* Derive the master kek. */
se::SetEncryptedAesKey128(pkg1::AesKeySlot_MasterKek, pkg1::AesKeySlot_MarikoKek, GetMarikoMasterKekSource(is_prod), se::AesBlockSize);
/* Derive the device master key source kek. */
se::SetEncryptedAesKey128(pkg1::AesKeySlot_DeviceMasterKeySourceKekMariko, pkg1::AesKeySlot_SecureBoot, GetDeviceMasterKeySourceKekSource(), se::AesBlockSize);
/* Clear the KEK, now that we're done using it. */
se::ClearAesKeySlot(pkg1::AesKeySlot_MarikoKek);
}
void DeriveMasterKekAndDeviceKey(bool is_prod) {
if (GetSocType() == fuse::SocType_Mariko) {
DeriveMasterKekAndDeviceKeyMariko(is_prod);
} else /* if (GetSocType() == fuse::SocType_Erista) */ {
DeriveMasterKekAndDeviceKeyErista(is_prod);
}
}
void DeriveMasterKey() {
if (GetSocType() == fuse::SocType_Mariko) {
se::SetEncryptedAesKey128(pkg1::AesKeySlot_Master, pkg1::AesKeySlot_MasterKek, GetMasterKeySource(), se::AesBlockSize);
} else /* if (GetSocType() == fuse::SocType_Erista) */ {
/* Nothing to do here; erista bootloader will have derived master key already. */
}
}
void SetupRandomKey(int slot, se::KeySlotLockFlags flags) {
/* Create an aligned buffer to hold the key. */
constexpr size_t KeySize = se::AesBlockSize;
util::AlignedBuffer<hw::DataCacheLineSize, KeySize> key;
/* Ensure data is consistent before triggering the SE. */
hw::FlushDataCache(key, KeySize);
hw::DataSynchronizationBarrierInnerShareable();
/* Generate random bytes into the key. */
se::GenerateRandomBytes(key, KeySize);
/* Ensure that the CPU sees consistent data. */
hw::DataSynchronizationBarrierInnerShareable();
hw::FlushDataCache(key, KeySize);
hw::DataSynchronizationBarrierInnerShareable();
/* Use the random bytes as a key source. */
se::SetEncryptedAesKey128(slot, pkg1::AesKeySlot_DeviceMaster, key, KeySize);
/* Lock the keyslot. */
se::LockAesKeySlot(slot, flags);
}
bool TestKeyGeneration(int generation, bool is_prod) {
/* Decrypt the vector chain from generation to start. */
int slot = pkg1::AesKeySlot_Master;
for (int i = generation; i > 0; --i) {
se::SetEncryptedAesKey128(pkg1::AesKeySlot_Temporary, slot, GetMasterKeyVector(is_prod, i), se::AesBlockSize);
slot = pkg1::AesKeySlot_Temporary;
}
/* Decrypt the final vector. */
u8 test_vector[se::AesBlockSize];
se::DecryptAes128(test_vector, se::AesBlockSize, slot, GetMasterKeyVector(is_prod, 0), se::AesBlockSize);
constexpr u8 ZeroBlock[se::AesBlockSize] = {};
return crypto::IsSameBytes(ZeroBlock, test_vector, se::AesBlockSize);
}
int DetermineKeyGeneration(bool is_prod) {
/* Test each generation in order. */
for (int generation = 0; generation < pkg1::KeyGeneration_Count; ++generation) {
if (TestKeyGeneration(generation, is_prod)) {
return generation;
}
}
/* We must have found a correct key generation. */
AMS_ABORT();
}
void DeriveAllMasterKeys(bool is_prod, u8 * const work_block) {
/* Determine the generation. */
const int generation = DetermineKeyGeneration(is_prod);
AMS_SECMON_LOG("KeyGen: %02X\n", static_cast<unsigned int>(generation));
/* Set the global generation. */
::ams::secmon::impl::SetKeyGeneration(generation);
/* Derive all old keys. */
int slot = pkg1::AesKeySlot_Master;
for (int i = generation; i > 0; --i) {
/* Decrypt the old master key. */
se::DecryptAes128(work_block, se::AesBlockSize, slot, GetMasterKeyVector(is_prod, i), se::AesBlockSize);
/* Set the old master key. */
SetMasterKey(i - 1, work_block, se::AesBlockSize);
/* Set the old master key into a temporary keyslot. */
se::SetAesKey(pkg1::AesKeySlot_Temporary, work_block, se::AesBlockSize);
/* Perform the next decryption with the older master key. */
slot = pkg1::AesKeySlot_Temporary;
}
}
void DeriveAllDeviceMasterKeys(bool is_prod, u8 * const work_block) {
/* Get the current key generation. */
const int current_generation = secmon::GetKeyGeneration();
/* Get the kek slot. */
const int kek_slot = GetSocType() == fuse::SocType_Mariko ? pkg1::AesKeySlot_DeviceMasterKeySourceKekMariko : pkg1::AesKeySlot_DeviceMasterKeySourceKekErista;
/* Iterate for all generations. */
for (int i = 0; i < pkg1::OldDeviceMasterKeyCount; ++i) {
const int generation = pkg1::KeyGeneration_4_0_0 + i;
/* Load the first master key into the temporary keyslot keyslot. */
LoadMasterKey(pkg1::AesKeySlot_Temporary, pkg1::KeyGeneration_1_0_0);
/* Decrypt the device master kek for the generation. */
se::SetEncryptedAesKey128(pkg1::AesKeySlot_Temporary, pkg1::AesKeySlot_Temporary, GetDeviceMasterKekSource(is_prod, i), se::AesBlockSize);
/* Decrypt the device master key source into the work block. */
se::DecryptAes128(work_block, se::AesBlockSize, kek_slot, GetDeviceMasterKeySourceSource(i), se::AesBlockSize);
/* If we're decrypting the current device master key, decrypt into the keyslot. */
if (generation == current_generation) {
se::SetEncryptedAesKey128(pkg1::AesKeySlot_DeviceMaster, pkg1::AesKeySlot_Temporary, work_block, se::AesBlockSize);
} else {
/* Otherwise, decrypt the work block into itself and set the old device master key. */
se::DecryptAes128(work_block, se::AesBlockSize, pkg1::AesKeySlot_Temporary, work_block, se::AesBlockSize);
/* Set the device master key. */
SetDeviceMasterKey(generation, work_block, se::AesBlockSize);
}
}
/* Clear and lock the Device Master Key Source Kek. */
se::ClearAesKeySlot(pkg1::AesKeySlot_DeviceMasterKeySourceKekMariko);
se::LockAesKeySlot(pkg1::AesKeySlot_DeviceMasterKeySourceKekMariko, se::KeySlotLockFlags_AllLockKek);
}
void DeriveAllKeys(bool is_prod) {
/* Get the ephemeral work block. */
u8 * const work_block = se::GetEphemeralWorkBlock();
ON_SCOPE_EXIT { util::ClearMemory(work_block, se::AesBlockSize); };
/* Lock the master key as a key. */
se::LockAesKeySlot(pkg1::AesKeySlot_Master, se::KeySlotLockFlags_AllLockKey);
/* Setup a random key to protect the old master and device master keys. */
SetupRandomKey(pkg1::AesKeySlot_RandomForKeyStorageWrap, se::KeySlotLockFlags_AllLockKey);
/* Derive the master keys. */
DeriveAllMasterKeys(is_prod, work_block);
/* Lock the master key as a kek. */
se::LockAesKeySlot(pkg1::AesKeySlot_Master, se::KeySlotLockFlags_AllLockKek);
/* Derive the device master keys. */
DeriveAllDeviceMasterKeys(is_prod, work_block);
/* Lock the device master key as a kek. */
se::LockAesKeySlot(pkg1::AesKeySlot_DeviceMaster, se::KeySlotLockFlags_AllLockKek);
/* Setup a random key to protect user keys. */
SetupRandomKey(pkg1::AesKeySlot_RandomForUserWrap, se::KeySlotLockFlags_AllLockKek);
}
void InitializeKeys() {
/* Read lock all aes keys. */
for (int i = 0; i < se::AesKeySlotCount; ++i) {
se::LockAesKeySlot(i, se::KeySlotLockFlags_AllReadLock);
}
/* Lock the secure monitor aes keys to be secmon only and non-readable. */
for (int i = pkg1::AesKeySlot_SecmonStart; i < pkg1::AesKeySlot_SecmonEnd; ++i) {
se::LockAesKeySlot(i, se::KeySlotLockFlags_KeyUse | se::KeySlotLockFlags_PerKey);
}
/* Lock the unused keyslots entirely. */
static_assert(pkg1::AesKeySlot_UserEnd <= pkg1::AesKeySlot_SecmonStart);
for (int i = pkg1::AesKeySlot_UserEnd; i < pkg1::AesKeySlot_SecmonStart; ++i) {
se::LockAesKeySlot(i, se::KeySlotLockFlags_AllLockKek);
}
/* Read lock all rsa keys. */
for (int i = 0; i < se::RsaKeySlotCount; ++i) {
se::LockRsaKeySlot(i, se::KeySlotLockFlags_KeyUse | se::KeySlotLockFlags_PerKey | se::KeySlotLockFlags_KeyRead);
}
/* Initialize the rng. */
se::InitializeRandom();
/* Determine whether we're production. */
const bool is_prod = IsProduction();
/* Derive the master kek and device key. */
/* NOTE: This is a no-op on erista, because fusee will have set up keys. */
DeriveMasterKekAndDeviceKey(is_prod);
/* Lock the device key as only usable as a kek. */
se::LockAesKeySlot(pkg1::AesKeySlot_Device, se::KeySlotLockFlags_AllLockKek);
/* Derive the master key. */
DeriveMasterKey();
/* Derive all other keys. */
DeriveAllKeys(is_prod);
}
}
namespace {
using namespace ams::mmu;
constexpr void UnmapPhysicalIdentityMappingImpl(u64 *l1, u64 *l2, u64 *l3) {
/* Invalidate the L3 entries for the tzram and iram boot code regions. */
InvalidateL3Entries(l3, MemoryRegionPhysicalTzram.GetAddress(), MemoryRegionPhysicalTzram.GetSize());
InvalidateL3Entries(l3, MemoryRegionPhysicalIramBootCode.GetAddress(), MemoryRegionPhysicalIramBootCode.GetSize());
/* Unmap the L2 entries corresponding to those L3 entries. */
InvalidateL2Entries(l2, MemoryRegionPhysicalIramL2.GetAddress(), MemoryRegionPhysicalIramL2.GetSize());
InvalidateL2Entries(l2, MemoryRegionPhysicalTzramL2.GetAddress(), MemoryRegionPhysicalTzramL2.GetSize());
/* Unmap the L1 entry corresponding to to those L2 entries. */
InvalidateL1Entries(l1, MemoryRegionPhysical.GetAddress(), MemoryRegionPhysical.GetSize());
}
constexpr void UnmapDramImpl(u64 *l1, u64 *l2, u64 *l3) {
/* Unmap the L1 entry corresponding to to the Dram entries. */
AMS_UNUSED(l2, l3);
InvalidateL1Entries(l1, MemoryRegionDram.GetAddress(), MemoryRegionDram.GetSize());
}
constexpr void UnmapMarikoProgramImpl(u64 *l1, u64 *l2, u64 *l3) {
/* Unmap the L1 entry corresponding to to the Dram entries. */
AMS_UNUSED(l1, l2);
InvalidateL3Entries(l3, MemoryRegionVirtualTzramMarikoProgram.GetAddress(), MemoryRegionVirtualTzramMarikoProgram.GetSize());
}
}
void InitializeColdBoot() {
/* Ensure that the system counters are valid. */
ValidateSystemCounters();
/* Set the security engine to Tzram Secure. */
se::SetTzramSecure();
/* Set the security engine to Per Key Secure. */
se::SetPerKeySecure();
/* Set the security engine to Context Save Secure. */
se::SetContextSaveSecure();
/* Setup the PMC registers. */
SetupPmcRegisters();
/* Lockout the scratch that we've just written. */
/* pmc::LockSecureRegisters(1); */
/* Generate a random srk. */
se::GenerateSrk();
/* Initialize the SE keyslots. */
InitializeKeys();
/* Save a test vector for the SE keyslots. */
SaveSecurityEngineAesKeySlotTestVector();
}
void UnmapPhysicalIdentityMapping() {
/* Get the tables. */
u64 * const l1 = MemoryRegionVirtualTzramL1PageTable.GetPointer<u64>();
u64 * const l2_l3 = MemoryRegionVirtualTzramL2L3PageTable.GetPointer<u64>();
/* Unmap. */
UnmapPhysicalIdentityMappingImpl(l1, l2_l3, l2_l3);
/* Ensure the mappings are consistent. */
secmon::boot::EnsureMappingConsistency();
}
void UnmapDram() {
/* Get the tables. */
u64 * const l1 = MemoryRegionVirtualTzramL1PageTable.GetPointer<u64>();
u64 * const l2_l3 = MemoryRegionVirtualTzramL2L3PageTable.GetPointer<u64>();
/* Unmap. */
UnmapDramImpl(l1, l2_l3, l2_l3);
/* Ensure the mappings are consistent. */
secmon::boot::EnsureMappingConsistency();
}
void LoadMarikoProgram() {
void * const mariko_program_dst = MemoryRegionVirtualTzramMarikoProgram.GetPointer<void>();
void * const mariko_program_src = MemoryRegionPhysicalMarikoProgramImage.GetPointer<void>();
const size_t mariko_program_size = MemoryRegionVirtualTzramMarikoProgram.GetSize();
if (fuse::GetSocType() == fuse::SocType_Mariko) {
/* On Mariko, we want to load the mariko program image into mariko tzram. */
std::memcpy(mariko_program_dst, mariko_program_src, mariko_program_size);
hw::FlushDataCache(mariko_program_dst, mariko_program_size);
} else {
/* On Erista, we don't have mariko-only-tzram, so unmap it. */
u64 * const l1 = MemoryRegionVirtualTzramL1PageTable.GetPointer<u64>();
u64 * const l2_l3 = MemoryRegionVirtualTzramL2L3PageTable.GetPointer<u64>();
UnmapMarikoProgramImpl(l1, l2_l3, l2_l3);
}
/* Clear the Mariko program image from DRAM. */
util::ClearMemory(mariko_program_src, mariko_program_size);
hw::FlushDataCache(mariko_program_src, mariko_program_size);
hw::DataSynchronizationBarrierInnerShareable();
/* Ensure the mappings are consistent. */
secmon::boot::EnsureMappingConsistency();
}
}