mirror of
https://github.com/Atmosphere-NX/Atmosphere.git
synced 2024-11-23 20:32:10 +00:00
428 lines
13 KiB
Markdown
428 lines
13 KiB
Markdown
# Cheats
|
|
Atmosphère supports Action-Replay style cheat codes, with cheats loaded off of the SD card.
|
|
|
|
## Cheat Loading Process
|
|
By default, Atmosphère will do the following when deciding whether to attach to a new application process:
|
|
|
|
+ Retrieve information about the new application process from `pm` and `loader`.
|
|
+ Check whether a user-defined key combination is held, and stop if not.
|
|
+ This defaults to "L is not held", but can be configured with override keys.
|
|
+ The ini key to configure this is `cheat_enable_key`.
|
|
+ Check whether the process is a real application, and stop if not.
|
|
+ This guards against applying cheat codes to the Homebrew Loader.
|
|
+ Attempt to load cheats from `/atmosphere/contents/<program_id>/cheats/<build_id>.txt`, where `build_id` is the hexadecimal representation of the first 8 bytes of the application's main executable's build id.
|
|
+ If no cheats are found, then the cheat manager will stop.
|
|
+ Open a kernel debug session for the new application process.
|
|
+ Signal to a system event that a new cheat process has been attached to.
|
|
|
|
This behavior ensures that cheat codes are only loaded when the user would want them to.
|
|
|
|
In cases where `dmnt` has not activated the cheat manager, but the user wants to make it do so anyway, the cheat manager's service API provides a `ForceOpenCheatProcess` command that homebrew can use. This command will cause the cheat manager to try to force itself to attach to the process.
|
|
|
|
By default, all cheat codes listed in the loaded .txt file will be toggled on. This is configurable by the user by editing the `atmosphere!dmnt_cheats_enabled_by_default` [system setting](configurations.md).
|
|
|
|
Users may use homebrew programs to toggle cheats on and off at runtime via the cheat manager's service API.
|
|
|
|
## Cheat Code Compatibility
|
|
Atmosphère manages cheat code through the execution of a small, custom virtual machine. Care has been taken to ensure that Atmosphère's cheat code format is fully backwards compatible with the pre-existing cheat code format, though new features have been added and bugs in the pre-existing cheat code applier have been fixed. Here is a short summary of the changes from the pre-existing format:
|
|
|
|
+ A number of bugs were fixed in the processing of conditional instructions.
|
|
+ The pre-existing implementation was fundamentally broken, and checked for the wrong value when detecting the end of a conditional block.
|
|
+ The pre-existing implementation also did not properly decode instructions, and instead linearly scanned for the terminator value. This caused problems if an instruction happened to encode a terminator inside its immediate values.
|
|
+ The pre-existing implementation did not bounds check, and thus certain conditional cheat codes could cause it to read out-of-bounds memory, and potentially crash due to a data abort.
|
|
+ Support was added for nesting conditional blocks.
|
|
+ An instruction was added to perform much more complex arbitrary arithmetic on two registers.
|
|
+ An instruction was added to allow writing the contents of register to a memory address specified by another register.
|
|
+ The pre-existing implementation did not correctly synchronize with the application process, and thus would cause heavy lag under certain circumstances (especially around loading screens). This has been fixed in Atmosphère's implementation.
|
|
|
|
## Cheat Code Format
|
|
The following provides documentation of the instruction format for the virtual machine used to manage cheat codes.
|
|
|
|
Typically, instruction type is encoded in the upper nybble of the first instruction u32.
|
|
|
|
### Code Type 0: Store Static Value to Memory
|
|
Code type 0 allows writing a static value to a memory address.
|
|
|
|
#### Encoding
|
|
`0TMR00AA AAAAAAAA VVVVVVVV (VVVVVVVV)`
|
|
|
|
+ T: Width of memory write (1, 2, 4, or 8 bytes).
|
|
+ M: Memory region to write to (0 = Main NSO, 1 = Heap).
|
|
+ R: Register to use as an offset from memory region base.
|
|
+ A: Immediate offset to use from memory region base.
|
|
+ V: Value to write.
|
|
|
|
---
|
|
|
|
### Code Type 1: Begin Conditional Block
|
|
Code type 1 performs a comparison of the contents of memory to a static value.
|
|
|
|
If the condition is not met, all instructions until the appropriate conditional block terminator are skipped.
|
|
|
|
#### Encoding
|
|
`1TMC00AA AAAAAAAA VVVVVVVV (VVVVVVVV)`
|
|
|
|
+ T: Width of memory write (1, 2, 4, or 8 bytes).
|
|
+ M: Memory region to write to (0 = Main NSO, 1 = Heap).
|
|
+ C: Condition to use, see below.
|
|
+ A: Immediate offset to use from memory region base.
|
|
+ V: Value to compare to.
|
|
|
|
#### Conditions
|
|
+ 1: >
|
|
+ 2: >=
|
|
+ 3: <
|
|
+ 4: <=
|
|
+ 5: ==
|
|
+ 6: !=
|
|
|
|
---
|
|
|
|
### Code Type 2: End Conditional Block
|
|
Code type 2 marks the end of a conditional block (started by Code Type 1 or Code Type 8).
|
|
|
|
#### Encoding
|
|
`20000000`
|
|
|
|
---
|
|
|
|
### Code Type 3: Start/End Loop
|
|
Code type 3 allows for iterating in a loop a fixed number of times.
|
|
|
|
#### Start Loop Encoding
|
|
`300R0000 VVVVVVVV`
|
|
|
|
+ R: Register to use as loop counter.
|
|
+ V: Number of iterations to loop.
|
|
|
|
#### End Loop Encoding
|
|
`310R0000`
|
|
|
|
+ R: Register to use as loop counter.
|
|
|
|
---
|
|
|
|
### Code Type 4: Load Register with Static Value
|
|
Code type 4 allows setting a register to a constant value.
|
|
|
|
#### Encoding
|
|
`400R0000 VVVVVVVV VVVVVVVV`
|
|
|
|
+ R: Register to use.
|
|
+ V: Value to load.
|
|
|
|
---
|
|
|
|
### Code Type 5: Load Register with Memory Value
|
|
Code type 5 allows loading a value from memory into a register, either using a fixed address or by dereferencing the destination register.
|
|
|
|
#### Load From Fixed Address Encoding
|
|
`5TMR00AA AAAAAAAA`
|
|
|
|
+ T: Width of memory read (1, 2, 4, or 8 bytes).
|
|
+ M: Memory region to write to (0 = Main NSO, 1 = Heap).
|
|
+ R: Register to load value into.
|
|
+ A: Immediate offset to use from memory region base.
|
|
|
|
#### Load from Register Address Encoding
|
|
`5TMR10AA AAAAAAAA`
|
|
|
|
+ T: Width of memory read (1, 2, 4, or 8 bytes).
|
|
+ M: Memory region to write to (0 = Main NSO, 1 = Heap).
|
|
+ R: Register to load value into.
|
|
+ A: Immediate offset to use from register R.
|
|
|
|
---
|
|
|
|
### Code Type 6: Store Static Value to Register Memory Address
|
|
Code type 6 allows writing a fixed value to a memory address specified by a register.
|
|
|
|
#### Encoding
|
|
`6T0RIor0 VVVVVVVV VVVVVVVV`
|
|
|
|
+ T: Width of memory write (1, 2, 4, or 8 bytes).
|
|
+ R: Register used as base memory address.
|
|
+ I: Increment register flag (0 = do not increment R, 1 = increment R by T).
|
|
+ o: Offset register enable flag (0 = do not add r to address, 1 = add r to address).
|
|
+ r: Register used as offset when o is 1.
|
|
+ V: Value to write to memory.
|
|
|
|
---
|
|
|
|
### Code Type 7: Legacy Arithmetic
|
|
Code type 7 allows performing arithmetic on registers.
|
|
|
|
However, it has been deprecated by Code type 9, and is only kept for backwards compatibility.
|
|
|
|
#### Encoding
|
|
`7T0RC000 VVVVVVVV`
|
|
|
|
+ T: Width of arithmetic operation (1, 2, 4, or 8 bytes).
|
|
+ R: Register to apply arithmetic to.
|
|
+ C: Arithmetic operation to apply, see below.
|
|
+ V: Value to use for arithmetic operation.
|
|
|
|
#### Arithmetic Types
|
|
+ 0: Addition
|
|
+ 1: Subtraction
|
|
+ 2: Multiplication
|
|
+ 3: Left Shift
|
|
+ 4: Right Shift
|
|
|
|
---
|
|
|
|
### Code Type 8: Begin Keypress Conditional Block
|
|
Code type 8 enters or skips a conditional block based on whether a key combination is pressed.
|
|
|
|
#### Encoding
|
|
`8kkkkkkk`
|
|
|
|
+ k: Keypad mask to check against, see below.
|
|
|
|
Note that for multiple button combinations, the bitmasks should be ORd together.
|
|
|
|
#### Keypad Values
|
|
Note: This is the direct output of `hidKeysDown()`.
|
|
|
|
+ 0000001: A
|
|
+ 0000002: B
|
|
+ 0000004: X
|
|
+ 0000008: Y
|
|
+ 0000010: Left Stick Pressed
|
|
+ 0000020: Right Stick Pressed
|
|
+ 0000040: L
|
|
+ 0000080: R
|
|
+ 0000100: ZL
|
|
+ 0000200: ZR
|
|
+ 0000400: Plus
|
|
+ 0000800: Minus
|
|
+ 0001000: Left
|
|
+ 0002000: Up
|
|
+ 0004000: Right
|
|
+ 0008000: Down
|
|
+ 0010000: Left Stick Left
|
|
+ 0020000: Left Stick Up
|
|
+ 0040000: Left Stick Right
|
|
+ 0080000: Left Stick Down
|
|
+ 0100000: Right Stick Left
|
|
+ 0200000: Right Stick Up
|
|
+ 0400000: Right Stick Right
|
|
+ 0800000: Right Stick Down
|
|
+ 1000000: SL
|
|
+ 2000000: SR
|
|
|
|
---
|
|
|
|
### Code Type 9: Perform Arithmetic
|
|
Code type 9 allows performing arithmetic on registers.
|
|
|
|
#### Register Arithmetic Encoding
|
|
`9TCRS0s0`
|
|
|
|
+ T: Width of arithmetic operation (1, 2, 4, or 8 bytes).
|
|
+ C: Arithmetic operation to apply, see below.
|
|
+ R: Register to store result in.
|
|
+ S: Register to use as left-hand operand.
|
|
+ s: Register to use as right-hand operand.
|
|
|
|
#### Immediate Value Arithmetic Encoding
|
|
`9TCRS100 VVVVVVVV (VVVVVVVV)`
|
|
|
|
+ T: Width of arithmetic operation (1, 2, 4, or 8 bytes).
|
|
+ C: Arithmetic operation to apply, see below.
|
|
+ R: Register to store result in.
|
|
+ S: Register to use as left-hand operand.
|
|
+ V: Value to use as right-hand operand.
|
|
|
|
#### Arithmetic Types
|
|
+ 0: Addition
|
|
+ 1: Subtraction
|
|
+ 2: Multiplication
|
|
+ 3: Left Shift
|
|
+ 4: Right Shift
|
|
+ 5: Logical And
|
|
+ 6: Logical Or
|
|
+ 7: Logical Not (discards right-hand operand)
|
|
+ 8: Logical Xor
|
|
+ 9: None/Move (discards right-hand operand)
|
|
|
|
---
|
|
|
|
### Code Type 10: Store Register to Memory Address
|
|
Code type 10 allows writing a register to memory.
|
|
|
|
#### Encoding
|
|
`ATSRIOxa (aaaaaaaa)`
|
|
|
|
+ T: Width of memory write (1, 2, 4, or 8 bytes).
|
|
+ S: Register to write to memory.
|
|
+ R: Register to use as base address.
|
|
+ I: Increment register flag (0 = do not increment R, 1 = increment R by T).
|
|
+ O: Offset type, see below.
|
|
+ x: Register used as offset when O is 1, Memory type when O is 3, 4 or 5.
|
|
+ a: Value used as offset when O is 2, 4 or 5.
|
|
|
|
#### Offset Types
|
|
+ 0: No Offset
|
|
+ 1: Use Offset Register
|
|
+ 2: Use Fixed Offset
|
|
+ 3: Memory Region + Base Register
|
|
+ 4: Memory Region + Relative Address (ignore address register)
|
|
+ 5: Memory Region + Relative Address + Offset Register
|
|
|
|
---
|
|
|
|
### Code Type 11: Reserved
|
|
Code Type 11 is currently reserved for future use.
|
|
|
|
---
|
|
|
|
### Code Type 12-15: Extended-Width Instruction
|
|
Code Types 12-15 signal to the VM to treat the upper two nybbles of the first dword as instruction type, instead of just the upper nybble.
|
|
|
|
This reserves an additional 64 opcodes for future use.
|
|
|
|
---
|
|
|
|
### Code Type 0xC0: Begin Register Conditional Block
|
|
Code type 0xC0 performs a comparison of the contents of a register and another value. This code support multiple operand types, see below.
|
|
|
|
If the condition is not met, all instructions until the appropriate conditional block terminator are skipped.
|
|
|
|
#### Encoding
|
|
```
|
|
C0TcSX##
|
|
C0TcS0Ma aaaaaaaa
|
|
C0TcS1Mr
|
|
C0TcS2Ra aaaaaaaa
|
|
C0TcS3Rr
|
|
C0TcS400 VVVVVVVV (VVVVVVVV)
|
|
C0TcS5X0
|
|
```
|
|
|
|
+ T: Width of memory write (1, 2, 4, or 8 bytes).
|
|
+ c: Condition to use, see below.
|
|
+ S: Source Register.
|
|
+ X: Operand Type, see below.
|
|
+ M: Memory Type (operand types 0 and 1).
|
|
+ R: Address Register (operand types 2 and 3).
|
|
+ a: Relative Address (operand types 0 and 2).
|
|
+ r: Offset Register (operand types 1 and 3).
|
|
+ X: Other Register (operand type 5).
|
|
+ V: Value to compare to (operand type 4).
|
|
|
|
#### Operand Type
|
|
+ 0: Memory Base + Relative Offset
|
|
+ 1: Memory Base + Offset Register
|
|
+ 2: Register + Relative Offset
|
|
+ 3: Register + Offset Register
|
|
+ 4: Static Value
|
|
+ 5: Other Register
|
|
|
|
#### Conditions
|
|
+ 1: >
|
|
+ 2: >=
|
|
+ 3: <
|
|
+ 4: <=
|
|
+ 5: ==
|
|
+ 6: !=
|
|
|
|
---
|
|
|
|
### Code Type 0xC1: Save or Restore Register
|
|
Code type 0xC1 performs saving or restoring of registers.
|
|
|
|
#### Encoding
|
|
`C10D0Sx0`
|
|
|
|
+ D: Destination index.
|
|
+ S: Source index.
|
|
+ x: Operand Type, see below.
|
|
|
|
#### Operand Type
|
|
+ 0: Restore register
|
|
+ 1: Save register
|
|
+ 2: Clear saved value
|
|
+ 3: Clear register
|
|
|
|
---
|
|
|
|
### Code Type 0xC2: Save or Restore Register with Mask
|
|
Code type 0xC2 performs saving or restoring of multiple registers using a bitmask.
|
|
|
|
#### Encoding
|
|
`C2x0XXXX`
|
|
|
|
+ x: Operand Type, see below.
|
|
+ X: 16-bit bitmask, bit i == save or restore register i.
|
|
|
|
#### Operand Type
|
|
+ 0: Restore register
|
|
+ 1: Save register
|
|
+ 2: Clear saved value
|
|
+ 3: Clear register
|
|
|
|
---
|
|
|
|
### Code Type 0xC3: Read or Write Static Register
|
|
Code type 0xC3 reads or writes a static register with a given register.
|
|
|
|
#### Encoding
|
|
`C3000XXx`
|
|
|
|
+ XX: Static register index, 0x00 to 0x7F for reading or 0x80 to 0xFF for writing.
|
|
+ x: Register index.
|
|
|
|
---
|
|
|
|
### Code Type 0xF0: Double Extended-Width Instruction
|
|
Code Type 0xF0 signals to the VM to treat the upper three nybbles of the first dword as instruction type, instead of just the upper nybble.
|
|
|
|
This reserves an additional 16 opcodes for future use.
|
|
|
|
---
|
|
|
|
### Code Type 0xFF0: Pause Process
|
|
Code type 0xFF0 pauses the current process.
|
|
|
|
#### Encoding
|
|
`FF0?????`
|
|
|
|
---
|
|
|
|
### Code Type 0xFF1: Resume Process
|
|
Code type 0xFF1 resumes the current process.
|
|
|
|
#### Encoding
|
|
`FF1?????`
|
|
|
|
---
|
|
|
|
### Code Type 0xFFF: Debug Log
|
|
Code type 0xFFF writes a debug log to the SD card under the folder `/atmosphere/cheat_vm_logs/`.
|
|
|
|
#### Encoding
|
|
```
|
|
FFFTIX##
|
|
FFFTI0Ma aaaaaaaa
|
|
FFFTI1Mr
|
|
FFFTI2Ra aaaaaaaa
|
|
FFFTI3Rr
|
|
FFFTI4X0
|
|
```
|
|
|
|
+ T: Width of memory write (1, 2, 4, or 8 bytes).
|
|
+ I: Log id.
|
|
+ X: Operand Type, see below.
|
|
+ M: Memory Type (operand types 0 and 1).
|
|
+ R: Address Register (operand types 2 and 3).
|
|
+ a: Relative Address (operand types 0 and 2).
|
|
+ r: Offset Register (operand types 1 and 3).
|
|
+ X: Value Register (operand type 4).
|
|
|
|
#### Operand Type
|
|
+ 0: Memory Base + Relative Offset
|
|
+ 1: Memory Base + Offset Register
|
|
+ 2: Register + Relative Offset
|
|
+ 3: Register + Offset Register
|
|
+ 4: Register Value
|