Atmosphere/libraries/libmesosphere/include/mesosphere/kern_k_capabilities.hpp
2020-07-31 14:50:52 -07:00

360 lines
16 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/>.
*/
#pragma once
#include <mesosphere/kern_common.hpp>
#include <mesosphere/kern_k_thread.hpp>
#include <mesosphere/kern_select_page_table.hpp>
#include <mesosphere/kern_svc.hpp>
namespace ams::kern {
class KCapabilities {
private:
static constexpr size_t SvcFlagCount = svc::NumSupervisorCalls / BITSIZEOF(u8);
static constexpr size_t IrqFlagCount = /* TODO */0x80;
enum class CapabilityType : u32 {
CorePriority = (1u << 3) - 1,
SyscallMask = (1u << 4) - 1,
MapRange = (1u << 6) - 1,
MapIoPage = (1u << 7) - 1,
MapRegion = (1u << 10) - 1,
InterruptPair = (1u << 11) - 1,
ProgramType = (1u << 13) - 1,
KernelVersion = (1u << 14) - 1,
HandleTable = (1u << 15) - 1,
DebugFlags = (1u << 16) - 1,
Invalid = 0u,
Padding = ~0u,
};
using RawCapabilityValue = util::BitPack32::Field<0, BITSIZEOF(util::BitPack32), u32>;
static constexpr CapabilityType GetCapabilityType(const util::BitPack32 cap) {
const u32 value = cap.Get<RawCapabilityValue>();
return static_cast<CapabilityType>((~value & (value + 1)) - 1);
}
static constexpr u32 GetCapabilityFlag(CapabilityType type) {
return static_cast<u32>(type) + 1;
}
static constexpr u32 CountTrailingZero(u32 flag) {
for (u32 i = 0; i < BITSIZEOF(u32); i++) {
if (flag & (1u << i)) {
return i;
}
}
return BITSIZEOF(u32);
}
static constexpr u32 GetCapabilityId(CapabilityType type) {
const u32 flag = GetCapabilityFlag(type);
if (std::is_constant_evaluated()) {
return CountTrailingZero(flag);
} else {
return static_cast<u32>(__builtin_ctz(flag));
}
}
template<size_t Index, size_t Count, typename T = u32>
using Field = util::BitPack32::Field<Index, Count, T>;
#define DEFINE_FIELD(name, prev, ...) using name = Field<prev::Next, __VA_ARGS__>
template<CapabilityType Type>
static constexpr inline u32 CapabilityFlag = []() -> u32 {
return static_cast<u32>(Type) + 1;
}();
template<CapabilityType Type>
static constexpr inline u32 CapabilityId = []() -> u32 {
const u32 flag = static_cast<u32>(Type) + 1;
if (std::is_constant_evaluated()) {
for (u32 i = 0; i < BITSIZEOF(u32); i++) {
if (flag & (1u << i)) {
return i;
}
}
return BITSIZEOF(u32);
} else {
return __builtin_ctz(flag);
}
}();
struct CorePriority {
using IdBits = Field<0, CapabilityId<CapabilityType::CorePriority> + 1>;
DEFINE_FIELD(LowestThreadPriority, IdBits, 6);
DEFINE_FIELD(HighestThreadPriority, LowestThreadPriority, 6);
DEFINE_FIELD(MinimumCoreId, HighestThreadPriority, 8);
DEFINE_FIELD(MaximumCoreId, MinimumCoreId, 8);
};
struct SyscallMask {
using IdBits = Field<0, CapabilityId<CapabilityType::SyscallMask> + 1>;
DEFINE_FIELD(Mask, IdBits, 24);
DEFINE_FIELD(Index, Mask, 3);
};
static constexpr u64 PhysicalMapAllowedMask = (1ul << 36) - 1;
struct MapRange {
using IdBits = Field<0, CapabilityId<CapabilityType::MapRange> + 1>;
DEFINE_FIELD(Address, IdBits, 24);
DEFINE_FIELD(ReadOnly, Address, 1, bool);
};
struct MapRangeSize {
using IdBits = Field<0, CapabilityId<CapabilityType::MapRange> + 1>;
DEFINE_FIELD(Pages, IdBits, 20);
DEFINE_FIELD(Reserved, Pages, 4);
DEFINE_FIELD(Normal, Reserved, 1, bool);
};
struct MapIoPage {
using IdBits = Field<0, CapabilityId<CapabilityType::MapIoPage> + 1>;
DEFINE_FIELD(Address, IdBits, 24);
};
enum class RegionType : u32 {
None = 0,
KernelTraceBuffer = 1,
OnMemoryBootImage = 2,
DTB = 3,
};
struct MapRegion {
using IdBits = Field<0, CapabilityId<CapabilityType::MapRegion> + 1>;
DEFINE_FIELD(Region0, IdBits, 6, RegionType);
DEFINE_FIELD(ReadOnly0, Region0, 1, bool);
DEFINE_FIELD(Region1, ReadOnly0, 6, RegionType);
DEFINE_FIELD(ReadOnly1, Region1, 1, bool);
DEFINE_FIELD(Region2, ReadOnly1, 6, RegionType);
DEFINE_FIELD(ReadOnly2, Region2, 1, bool);
};
static const u32 PaddingInterruptId = 0x3FF;
struct InterruptPair {
using IdBits = Field<0, CapabilityId<CapabilityType::InterruptPair> + 1>;
DEFINE_FIELD(InterruptId0, IdBits, 10);
DEFINE_FIELD(InterruptId1, InterruptId0, 10);
};
struct ProgramType {
using IdBits = Field<0, CapabilityId<CapabilityType::ProgramType> + 1>;
DEFINE_FIELD(Type, IdBits, 3);
DEFINE_FIELD(Reserved, Type, 15);
};
struct KernelVersion {
using IdBits = Field<0, CapabilityId<CapabilityType::KernelVersion> + 1>;
DEFINE_FIELD(MinorVersion, IdBits, 4);
DEFINE_FIELD(MajorVersion, MinorVersion, 13);
};
struct HandleTable {
using IdBits = Field<0, CapabilityId<CapabilityType::HandleTable> + 1>;
DEFINE_FIELD(Size, IdBits, 10);
DEFINE_FIELD(Reserved, Size, 6);
};
struct DebugFlags {
using IdBits = Field<0, CapabilityId<CapabilityType::DebugFlags> + 1>;
DEFINE_FIELD(AllowDebug, IdBits, 1, bool);
DEFINE_FIELD(ForceDebug, AllowDebug, 1, bool);
DEFINE_FIELD(Reserved, ForceDebug, 13);
};
#undef DEFINE_FIELD
static constexpr u32 InitializeOnceFlags = CapabilityFlag<CapabilityType::CorePriority> |
CapabilityFlag<CapabilityType::ProgramType> |
CapabilityFlag<CapabilityType::KernelVersion> |
CapabilityFlag<CapabilityType::HandleTable> |
CapabilityFlag<CapabilityType::DebugFlags>;
private:
u8 svc_access_flags[SvcFlagCount]{};
u8 irq_access_flags[IrqFlagCount]{};
u64 core_mask{};
u64 priority_mask{};
util::BitPack32 debug_capabilities{0};
s32 handle_table_size{};
util::BitPack32 intended_kernel_version{0};
u32 program_type{};
private:
static constexpr ALWAYS_INLINE void SetSvcAllowedImpl(u8 *data, u32 id) {
constexpr size_t BitsPerWord = BITSIZEOF(*data);
MESOSPHERE_ASSERT(id < svc::SvcId_Count);
data[id / BitsPerWord] |= (1ul << (id % BitsPerWord));
}
static constexpr ALWAYS_INLINE void ClearSvcAllowedImpl(u8 *data, u32 id) {
constexpr size_t BitsPerWord = BITSIZEOF(*data);
MESOSPHERE_ASSERT(id < svc::SvcId_Count);
data[id / BitsPerWord] &= ~(1ul << (id % BitsPerWord));
}
static constexpr ALWAYS_INLINE bool GetSvcAllowedImpl(u8 *data, u32 id) {
constexpr size_t BitsPerWord = BITSIZEOF(*data);
MESOSPHERE_ASSERT(id < svc::SvcId_Count);
return (data[id / BitsPerWord] & (1ul << (id % BitsPerWord))) != 0;
}
bool SetSvcAllowed(u32 id) {
if (id < BITSIZEOF(this->svc_access_flags)) {
SetSvcAllowedImpl(this->svc_access_flags, id);
return true;
} else {
return false;
}
}
bool SetInterruptPermitted(u32 id) {
constexpr size_t BitsPerWord = BITSIZEOF(this->irq_access_flags[0]);
if (id < BITSIZEOF(this->irq_access_flags)) {
this->irq_access_flags[id / BitsPerWord] |= (1ul << (id % BitsPerWord));
return true;
} else {
return false;
}
}
Result SetCorePriorityCapability(const util::BitPack32 cap);
Result SetSyscallMaskCapability(const util::BitPack32 cap, u32 &set_svc);
Result MapRange(const util::BitPack32 cap, const util::BitPack32 size_cap, KProcessPageTable *page_table);
Result MapIoPage(const util::BitPack32 cap, KProcessPageTable *page_table);
Result MapRegion(const util::BitPack32 cap, KProcessPageTable *page_table);
Result SetInterruptPairCapability(const util::BitPack32 cap);
Result SetProgramTypeCapability(const util::BitPack32 cap);
Result SetKernelVersionCapability(const util::BitPack32 cap);
Result SetHandleTableCapability(const util::BitPack32 cap);
Result SetDebugFlagsCapability(const util::BitPack32 cap);
Result SetCapability(const util::BitPack32 cap, u32 &set_flags, u32 &set_svc, KProcessPageTable *page_table);
Result SetCapabilities(const u32 *caps, s32 num_caps, KProcessPageTable *page_table);
Result SetCapabilities(svc::KUserPointer<const u32 *> user_caps, s32 num_caps, KProcessPageTable *page_table);
public:
constexpr KCapabilities() = default;
Result Initialize(const u32 *caps, s32 num_caps, KProcessPageTable *page_table);
Result Initialize(svc::KUserPointer<const u32 *> user_caps, s32 num_caps, KProcessPageTable *page_table);
constexpr u64 GetCoreMask() const { return this->core_mask; }
constexpr u64 GetPriorityMask() const { return this->priority_mask; }
constexpr s32 GetHandleTableSize() const { return this->handle_table_size; }
ALWAYS_INLINE void CopySvcPermissionsTo(KThread::StackParameters &sp) const {
static_assert(sizeof(svc_access_flags) == sizeof(sp.svc_permission));
/* Copy permissions. */
std::memcpy(sp.svc_permission, this->svc_access_flags, sizeof(this->svc_access_flags));
/* Clear specific SVCs based on our state. */
ClearSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException);
ClearSvcAllowedImpl(sp.svc_permission, svc::SvcId_SynchronizePreemptionState);
if (sp.is_pinned) {
ClearSvcAllowedImpl(sp.svc_permission, svc::SvcId_GetInfo);
}
}
ALWAYS_INLINE void CopyPinnedSvcPermissionsTo(KThread::StackParameters &sp) const {
static_assert(sizeof(svc_access_flags) == sizeof(sp.svc_permission));
/* Clear all permissions. */
std::memset(sp.svc_permission, 0, sizeof(this->svc_access_flags));
/* Set specific SVCs based on our state. */
SetSvcAllowedImpl(sp.svc_permission, svc::SvcId_SynchronizePreemptionState);
if (GetSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException)) {
SetSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException);
SetSvcAllowedImpl(sp.svc_permission, svc::SvcId_GetInfo);
}
}
ALWAYS_INLINE void CopyUnpinnedSvcPermissionsTo(KThread::StackParameters &sp) const {
static_assert(sizeof(svc_access_flags) == sizeof(sp.svc_permission));
/* Get whether we have access to return from exception. */
const bool return_from_exception = GetSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException);
/* Copy permissions. */
std::memcpy(sp.svc_permission, this->svc_access_flags, sizeof(this->svc_access_flags));
/* Clear/Set specific SVCs based on our state. */
ClearSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException);
ClearSvcAllowedImpl(sp.svc_permission, svc::SvcId_SynchronizePreemptionState);
if (return_from_exception) {
SetSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException);
}
}
ALWAYS_INLINE void CopyEnterExceptionSvcPermissionsTo(KThread::StackParameters &sp) {
static_assert(sizeof(svc_access_flags) == sizeof(sp.svc_permission));
/* Set ReturnFromException if allowed. */
if (GetSvcAllowedImpl(this->svc_access_flags, svc::SvcId_ReturnFromException)) {
SetSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException);
}
/* Set GetInfo if allowed. */
if (GetSvcAllowedImpl(this->svc_access_flags, svc::SvcId_GetInfo)) {
SetSvcAllowedImpl(sp.svc_permission, svc::SvcId_GetInfo);
}
}
ALWAYS_INLINE void CopyLeaveExceptionSvcPermissionsTo(KThread::StackParameters &sp) {
static_assert(sizeof(svc_access_flags) == sizeof(sp.svc_permission));
/* Clear ReturnFromException. */
ClearSvcAllowedImpl(sp.svc_permission, svc::SvcId_ReturnFromException);
/* If pinned, clear GetInfo. */
if (sp.is_pinned) {
ClearSvcAllowedImpl(sp.svc_permission, svc::SvcId_GetInfo);
}
}
constexpr bool IsPermittedInterrupt(u32 id) const {
constexpr size_t BitsPerWord = BITSIZEOF(this->irq_access_flags[0]);
if (id < BITSIZEOF(this->irq_access_flags)) {
return (this->irq_access_flags[id / BitsPerWord] & (1ul << (id % BitsPerWord))) != 0;
} else {
return false;
}
}
constexpr bool IsPermittedDebug() const {
return this->debug_capabilities.Get<DebugFlags::AllowDebug>();
}
constexpr bool CanForceDebug() const {
return this->debug_capabilities.Get<DebugFlags::ForceDebug>();
}
};
}