1#![allow(clippy::arithmetic_side_effects)]
2use crate::{
16 ebpf,
17 elf::Executable,
18 error::{EbpfError, ProgramResult},
19 interpreter::Interpreter,
20 memory_region::MemoryMapping,
21 program::{BuiltinFunction, BuiltinProgram, FunctionRegistry, SBPFVersion},
22 static_analysis::{Analysis, DummyContextObject, RegisterTraceEntry},
23};
24pub use defaults::get_stack_frame_size;
26use std::{collections::BTreeMap, fmt::Debug, marker::PhantomData, mem::offset_of, ptr};
27
28#[cfg(feature = "shuttle-test")]
29use shuttle::sync::Arc;
30#[cfg(not(feature = "shuttle-test"))]
31use std::sync::Arc;
32
33#[cfg(all(feature = "jit", not(feature = "shuttle-test")))]
34use rand::{thread_rng, Rng};
35#[cfg(all(feature = "jit", feature = "shuttle-test"))]
36use shuttle::rand::{thread_rng, Rng};
37
38#[cfg(feature = "jit")]
40pub fn get_runtime_environment_key() -> i32 {
41 static RUNTIME_ENVIRONMENT_KEY: std::sync::OnceLock<i32> = std::sync::OnceLock::new();
42 *RUNTIME_ENVIRONMENT_KEY.get_or_init(|| thread_rng().gen::<i32>() >> 1)
43}
44
45#[cfg(not(feature = "jit"))]
46pub fn get_runtime_environment_key() -> i32 {
47 0
48}
49
50pub(crate) mod defaults {
52 const DEFAULT_STACK_FRAME_SIZE: usize = 4_096;
53
54 #[cfg(feature = "conf-stack-frame-size")]
65 #[inline(always)]
66 pub fn get_stack_frame_size() -> usize {
67 static STACK_FRAME_SIZE_CACHE: std::sync::OnceLock<usize> = std::sync::OnceLock::new();
68 *STACK_FRAME_SIZE_CACHE.get_or_init(|| {
69 let size = std::env::var("VM_STACK_FRAME_SIZE")
70 .ok()
71 .and_then(|v| {
72 v.parse::<usize>().ok().filter(|sfz| *sfz > 0).or_else(|| {
73 log::warn!(
74 "Invalid VM_STACK_FRAME_SIZE={}, falling back to {}.",
75 v,
76 DEFAULT_STACK_FRAME_SIZE
77 );
78 None
79 })
80 })
81 .unwrap_or(DEFAULT_STACK_FRAME_SIZE);
82 if size != DEFAULT_STACK_FRAME_SIZE {
83 log::warn!(
84 "VM_STACK_FRAME_SIZE is set to {} (default: {}).",
85 size,
86 DEFAULT_STACK_FRAME_SIZE
87 );
88 }
89 size
90 })
91 }
92
93 #[cfg(not(feature = "conf-stack-frame-size"))]
95 pub const fn get_stack_frame_size() -> usize {
96 DEFAULT_STACK_FRAME_SIZE
97 }
98}
99
100pub enum ExecutionMode {
102 Interpreted,
104 Jit,
108 PreferJit,
110}
111
112#[derive(Debug, Clone, PartialEq, Eq)]
114pub struct Config {
115 pub max_call_depth: usize,
117 pub stack_frame_size: usize,
119 pub enable_address_translation: bool,
121 pub enable_stack_frame_gaps: bool,
123 pub instruction_meter_checkpoint_distance: usize,
125 pub enable_instruction_meter: bool,
127 pub enable_register_tracing: bool,
129 pub enable_symbol_and_section_labels: bool,
131 pub reject_broken_elfs: bool,
133 #[cfg(feature = "jit")]
134 pub noop_instruction_rate: u32,
136 #[cfg(feature = "jit")]
137 pub sanitize_user_provided_values: bool,
139 pub optimize_rodata: bool,
141 pub aligned_memory_mapping: bool,
143 pub enabled_sbpf_versions: std::ops::RangeInclusive<SBPFVersion>,
145}
146
147impl Config {
148 pub fn stack_size(&self) -> usize {
150 self.stack_frame_size * self.max_call_depth
151 }
152}
153
154impl Default for Config {
155 fn default() -> Self {
156 Self {
157 max_call_depth: 64,
158 stack_frame_size: defaults::get_stack_frame_size(),
159 enable_address_translation: true,
160 enable_stack_frame_gaps: true,
161 instruction_meter_checkpoint_distance: 10000,
162 enable_instruction_meter: true,
163 enable_register_tracing: false,
164 enable_symbol_and_section_labels: false,
165 reject_broken_elfs: false,
166 #[cfg(feature = "jit")]
167 noop_instruction_rate: 256,
168 #[cfg(feature = "jit")]
169 sanitize_user_provided_values: true,
170 optimize_rodata: true,
171 aligned_memory_mapping: false,
172 enabled_sbpf_versions: SBPFVersion::V0..=SBPFVersion::V4,
173 }
174 }
175}
176
177impl<C: ContextObject> Executable<C> {
179 pub fn from_elf(elf_bytes: &[u8], loader: Arc<BuiltinProgram<C>>) -> Result<Self, EbpfError> {
181 let executable = Executable::load(elf_bytes, loader)?;
182 Ok(executable)
183 }
184 pub fn from_text_bytes(
186 text_bytes: &[u8],
187 loader: Arc<BuiltinProgram<C>>,
188 sbpf_version: SBPFVersion,
189 function_registry: FunctionRegistry<usize>,
190 ) -> Result<Self, EbpfError> {
191 Executable::new_from_text_bytes(text_bytes, loader, sbpf_version, function_registry)
192 .map_err(EbpfError::ElfError)
193 }
194}
195
196pub trait ContextObject {
198 fn consume(&mut self, amount: u64);
200 fn get_remaining(&self) -> u64;
202 fn active_mapping_ptr(&mut self) -> ptr::NonNull<MemoryMapping>;
204}
205
206pub struct DynamicAnalysis {
208 pub edge_counter_max: usize,
210 pub edges: BTreeMap<usize, BTreeMap<usize, usize>>,
212}
213
214impl DynamicAnalysis {
215 pub fn new(register_trace: &[[u64; 12]], analysis: &Analysis) -> Self {
217 let mut result = Self {
218 edge_counter_max: 0,
219 edges: BTreeMap::new(),
220 };
221 let mut last_basic_block = usize::MAX;
222 for traced_instruction in register_trace.iter() {
223 let pc = traced_instruction[11] as usize;
224 if analysis.cfg_nodes.contains_key(&pc) {
225 let counter = result
226 .edges
227 .entry(last_basic_block)
228 .or_default()
229 .entry(pc)
230 .or_insert(0);
231 *counter += 1;
232 result.edge_counter_max = result.edge_counter_max.max(*counter);
233 last_basic_block = pc;
234 }
235 }
236 result
237 }
238}
239
240#[derive(Clone, Default)]
242pub struct CallFrame {
243 pub caller_saved_registers: [u64; ebpf::SCRATCH_REGS],
245 pub frame_pointer: u64,
247 pub target_pc: u64,
249}
250
251pub enum RuntimeEnvironmentSlot {
253 HostStackPointer = offset_of!(EbpfVm<DummyContextObject>, host_stack_pointer) as isize,
255 CallDepth = offset_of!(EbpfVm<DummyContextObject>, call_depth) as isize,
257 ContextObjectPointer = offset_of!(EbpfVm<DummyContextObject>, context_object_pointer) as isize,
259 PreviousInstructionMeter =
261 offset_of!(EbpfVm<DummyContextObject>, previous_instruction_meter) as isize,
262 DueInsnCount = offset_of!(EbpfVm<DummyContextObject>, due_insn_count) as isize,
264 StopwatchNumerator = offset_of!(EbpfVm<DummyContextObject>, stopwatch_numerator) as isize,
266 StopwatchDenominator = offset_of!(EbpfVm<DummyContextObject>, stopwatch_denominator) as isize,
268 Registers = offset_of!(EbpfVm<DummyContextObject>, registers) as isize,
270 ProgramResult = offset_of!(EbpfVm<DummyContextObject>, program_result) as isize,
272 MemoryMapping = offset_of!(EbpfVm<DummyContextObject>, memory_mapping) as isize,
274 RegisterTrace = offset_of!(EbpfVm<DummyContextObject>, register_trace) as isize,
276}
277
278#[repr(C)]
334pub struct EbpfVm<'a, C: ContextObject> {
335 pub host_stack_pointer: *mut u64,
337 pub call_depth: u64,
342 pub(crate) context_object_pointer: ptr::NonNull<C>,
344 context_object_lifetime: PhantomData<&'a mut C>,
346 pub previous_instruction_meter: u64,
348 pub due_insn_count: u64,
350 pub stopwatch_numerator: u64,
352 pub stopwatch_denominator: u64,
354 pub registers: [u64; 12],
356 pub program_result: ProgramResult,
358 pub(crate) memory_mapping: ptr::NonNull<MemoryMapping>,
360 pub loader: Arc<BuiltinProgram<C>>,
362 pub register_trace: Vec<RegisterTraceEntry>,
364 #[cfg(feature = "debugger")]
366 pub debug_port: Option<u16>,
367 #[cfg(feature = "debugger")]
369 pub debug_metadata: Option<String>,
370}
371
372impl<'a, C: ContextObject> EbpfVm<'a, C> {
373 pub fn new(
375 loader: Arc<BuiltinProgram<C>>,
376 sbpf_version: SBPFVersion,
377 context_object: &'a mut C,
378 stack_len: usize,
379 ) -> Self {
380 let config = loader.get_config();
381 let mut registers = [0u64; 12];
382 registers[ebpf::FRAME_PTR_REG] =
383 ebpf::MM_STACK_START.saturating_add(if !sbpf_version.manual_stack_frame_bump() {
384 config.stack_frame_size
385 } else {
386 stack_len
387 } as u64);
388
389 let memory_mapping = context_object.active_mapping_ptr();
390 EbpfVm {
391 host_stack_pointer: std::ptr::null_mut(),
392 call_depth: 0,
393 context_object_pointer: ptr::NonNull::from_mut(context_object),
394 context_object_lifetime: PhantomData,
395 previous_instruction_meter: 0,
396 due_insn_count: 0,
397 stopwatch_numerator: 0,
398 stopwatch_denominator: 0,
399 registers,
400 program_result: ProgramResult::Ok(0),
401 memory_mapping,
402 loader,
403 #[cfg(feature = "debugger")]
404 debug_port: std::env::var("VM_DEBUG_PORT")
405 .ok()
406 .and_then(|v| v.parse::<u16>().ok()),
407 #[cfg(feature = "debugger")]
408 debug_metadata: None,
409 register_trace: Vec::default(),
410 }
411 }
412
413 pub fn execute_program(
424 &mut self,
425 executable: &Executable<C>,
426 mode: &mut ExecutionMode,
427 call_frames: &mut [CallFrame],
428 ) -> (u64, ProgramResult) {
429 debug_assert!(Arc::ptr_eq(&self.loader, executable.get_loader()));
430 self.registers[11] = executable.get_entrypoint_instruction_offset() as u64;
431 let config = executable.get_config();
432 let initial_insn_count = self.context().get_remaining();
433 self.previous_instruction_meter = initial_insn_count;
434 self.due_insn_count = 0;
435 self.program_result = ProgramResult::Ok(0);
436
437 'execute: {
438 match *mode {
439 ExecutionMode::Interpreted => {}
440
441 #[cfg(all(feature = "jit", not(target_os = "windows"), target_arch = "x86_64"))]
442 ExecutionMode::PreferJit => {
443 if let Some(compiled_program) = executable.get_compiled_program() {
444 *mode = ExecutionMode::Jit;
445 break 'execute compiled_program.invoke(config, self, self.registers);
446 }
447 }
448 #[cfg(not(all(
449 feature = "jit",
450 not(target_os = "windows"),
451 target_arch = "x86_64"
452 )))]
453 ExecutionMode::PreferJit => {}
454
455 #[cfg(all(feature = "jit", not(target_os = "windows"), target_arch = "x86_64"))]
456 ExecutionMode::Jit => {
457 let Some(compiled_program) = executable.get_compiled_program() else {
458 return (0, ProgramResult::Err(EbpfError::JitNotCompiled));
459 };
460 *mode = ExecutionMode::Jit;
461 break 'execute compiled_program.invoke(config, self, self.registers);
462 }
463 #[cfg(not(all(
464 feature = "jit",
465 not(target_os = "windows"),
466 target_arch = "x86_64"
467 )))]
468 ExecutionMode::Jit => return (0, ProgramResult::Err(EbpfError::JitNotCompiled)),
469 }
470
471 *mode = ExecutionMode::Interpreted;
472 let interpreter = Interpreter::new(self, executable, self.registers, call_frames);
473 break 'execute run_interpreter(interpreter);
474 }
475
476 let instruction_count = if config.enable_instruction_meter {
477 let due_insn_count = self.due_insn_count;
478 let context = self.context();
479 context.consume(due_insn_count);
480 initial_insn_count.saturating_sub(context.get_remaining())
481 } else {
482 0
483 };
484 let mut result = ProgramResult::Ok(0);
485 std::mem::swap(&mut result, &mut self.program_result);
486 (instruction_count, result)
487 }
488
489 pub fn invoke_function(&mut self, function: BuiltinFunction<C>) {
491 function(
492 self.encrypted_host_address(),
493 self.registers[1],
494 self.registers[2],
495 self.registers[3],
496 self.registers[4],
497 self.registers[5],
498 );
499 }
500
501 pub(crate) fn encrypted_host_address(&mut self) -> EncryptedHostAddressToEbpfVm<C> {
507 let addr = (&raw mut *self).expose_provenance() as isize;
508 EncryptedHostAddressToEbpfVm(
509 addr.wrapping_add(get_runtime_environment_key() as isize) as usize as u64,
510 PhantomData,
511 )
512 }
513
514 pub fn context(&mut self) -> &mut C {
516 unsafe { self.context_object_pointer.as_mut() }
526 }
527
528 pub(crate) fn memory(&mut self) -> &mut MemoryMapping {
531 unsafe { self.memory_mapping.as_mut() }
537 }
538}
539
540#[repr(transparent)]
542pub struct EncryptedHostAddressToEbpfVm<C>(
543 pub(crate) u64,
546 PhantomData<C>,
547);
548
549impl<C: ContextObject> EncryptedHostAddressToEbpfVm<C> {
550 pub unsafe fn with_vm<R>(&mut self, cb: impl FnOnce(&mut EbpfVm<'_, C>) -> R) -> R {
558 let addr = (self.0 as usize as isize)
559 .wrapping_sub(crate::vm::get_runtime_environment_key() as isize);
560 let vm = unsafe {
564 std::ptr::with_exposed_provenance_mut::<crate::vm::EbpfVm<C>>(addr as usize)
565 .as_mut()
566 .unwrap()
567 };
568 cb(vm)
569 }
570}
571
572#[cold]
573#[inline(never)]
574#[cfg(feature = "debugger")]
575fn run_interpreter<C: ContextObject>(mut interpreter: Interpreter<C>) {
576 let debug_port = interpreter.vm.debug_port.clone();
577 if let Some(debug_port) = debug_port {
578 crate::debugger::execute(&mut interpreter, debug_port);
579 } else {
580 while interpreter.step() {}
581 }
582}
583
584#[cold]
585#[inline(never)]
586#[cfg(not(feature = "debugger"))]
587fn run_interpreter<C: ContextObject>(mut interpreter: Interpreter<C>) {
588 while interpreter.step() {}
589}
590
591#[cfg(test)]
592mod tests {
593 use crate::{
594 memory_region::MemoryMapping,
595 program::{BuiltinProgram, SBPFVersion},
596 vm::{Config, ContextObject, RuntimeEnvironmentSlot},
597 };
598 use std::{ptr::NonNull, sync::Arc};
599
600 #[test]
601 fn test_runtime_environment_slots() {
602 struct DummyContextObject(MemoryMapping);
603 impl ContextObject for DummyContextObject {
604 fn consume(&mut self, _: u64) {
605 todo!()
606 }
607 fn get_remaining(&self) -> u64 {
608 todo!()
609 }
610 fn active_mapping_ptr(&mut self) -> NonNull<MemoryMapping> {
611 NonNull::from_mut(&mut self.0)
612 }
613 }
614 let version = SBPFVersion::V4;
615 let config = Config::default();
616 let mut context_object =
617 unsafe { DummyContextObject(MemoryMapping::new(vec![], &config, version).unwrap()) };
618 let env = super::EbpfVm::new(
619 Arc::new(BuiltinProgram::new_mock()),
620 version,
621 &mut context_object,
622 4096,
623 );
624
625 macro_rules! check_slot {
626 ($env:expr, $entry:ident, $slot:ident) => {
627 assert_eq!(
628 unsafe {
629 std::ptr::addr_of!($env.$entry)
630 .cast::<u8>()
631 .offset_from(std::ptr::addr_of!($env).cast::<u8>()) as usize
632 },
633 RuntimeEnvironmentSlot::$slot as usize,
634 );
635 };
636 }
637
638 check_slot!(env, host_stack_pointer, HostStackPointer);
639 check_slot!(env, call_depth, CallDepth);
640 check_slot!(env, context_object_pointer, ContextObjectPointer);
641 check_slot!(env, previous_instruction_meter, PreviousInstructionMeter);
642 check_slot!(env, due_insn_count, DueInsnCount);
643 check_slot!(env, stopwatch_numerator, StopwatchNumerator);
644 check_slot!(env, stopwatch_denominator, StopwatchDenominator);
645 check_slot!(env, registers, Registers);
646 check_slot!(env, program_result, ProgramResult);
647 check_slot!(env, memory_mapping, MemoryMapping);
648 check_slot!(env, register_trace, RegisterTrace);
649 }
650}