3 Commits

77 changed files with 189456 additions and 236710 deletions

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@ -12,8 +12,8 @@ jobs:
name: Format
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v5
- uses: actions/setup-python@v6
- uses: actions/checkout@v4
- uses: actions/setup-python@v5
with:
python-version: "3.x"
- uses: pre-commit/action@v3.0.1

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@ -21,7 +21,7 @@ ci:
repos:
# Standard hooks
- repo: https://github.com/pre-commit/pre-commit-hooks
rev: v6.0.0
rev: v4.6.0
hooks:
- id: check-added-large-files
- id: check-case-conflict
@ -36,19 +36,19 @@ repos:
- id: trailing-whitespace
- repo: https://github.com/astral-sh/ruff-pre-commit
rev: "v0.13.2"
rev: "v0.4.2"
hooks:
- id: ruff
args: ["--fix", "--show-fixes"]
- id: ruff-format
exclude: ^(docs)|^(tests)|^(examples)
exclude: ^(tests/|examples/|docs/)
# Checking static types
- repo: https://github.com/pre-commit/mirrors-mypy
rev: "v1.18.2"
rev: "v1.10.0"
hooks:
- id: mypy
exclude: ^(tests)|^(examples)
exclude: ^(tests/|examples/)
additional_dependencies: [types-setuptools]
# Changes tabs to spaces

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@ -1,13 +1,13 @@
## Short term
- Implement enough functionality to port the BCC tutorial examples in PythonBPF
- Static Typing
- Add all maps
- XDP support in pylibbpf
- ringbuf support
- Add oneline IfExpr conditionals (wishlist)
- recursive expression resolution
## Long term
- Refactor the codebase to be better than a hackathon project
- Port to C++ and use actual LLVM?
- Fix struct_kioctx issue in the vmlinux transpiler

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@ -12,7 +12,7 @@
"from pythonbpf import bpf, map, section, bpfglobal, BPF\n",
"from pythonbpf.helper import pid\n",
"from pythonbpf.maps import HashMap\n",
"from pylibbpf import BpfMap\n",
"from pylibbpf import *\n",
"from ctypes import c_void_p, c_int64, c_uint64, c_int32\n",
"import matplotlib.pyplot as plt"
]

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@ -22,9 +22,5 @@ def LICENSE() -> str:
b = BPF()
b.load_and_attach()
if b.is_loaded() and b.is_attached():
print("Successfully loaded and attached")
else:
print("Could not load successfully")
# Now cat /sys/kernel/debug/tracing/trace_pipe to see results of the execve syscall.

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@ -1,27 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, BPF
from ctypes import c_void_p, c_int64
@bpf
@section("kretprobe/do_unlinkat")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
return c_int64(0)
@bpf
@section("kprobe/do_unlinkat")
def hello_world2(ctx: c_void_p) -> c_int64:
print("Hello, World!")
return c_int64(0)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
b = BPF()
b.load_and_attach()
while True:
print("running")
# Now cat /sys/kernel/debug/tracing/trace_pipe to see results of unlink kprobe.

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@ -21,17 +21,17 @@ def last() -> HashMap:
@section("tracepoint/syscalls/sys_enter_sync")
def do_trace(ctx: c_void_p) -> c_int64:
key = 0
tsp = last.lookup(key)
tsp = last().lookup(key)
if tsp:
kt = ktime()
delta = kt - tsp
if delta < 1000000000:
time_ms = delta // 1000000
print(f"sync called within last second, last {time_ms} ms ago")
last.delete(key)
last().delete(key)
else:
kt = ktime()
last.update(key, kt)
last().update(key, kt)
return c_int64(0)

File diff suppressed because it is too large Load Diff

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@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
[project]
name = "pythonbpf"
version = "0.1.4"
version = "0.1.3"
description = "Reduced Python frontend for eBPF"
authors = [
{ name = "r41k0u", email="pragyanshchaturvedi18@gmail.com" },

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@ -1,191 +0,0 @@
import ast
import logging
from llvmlite import ir
from dataclasses import dataclass
from typing import Any
from pythonbpf.helper import HelperHandlerRegistry
from pythonbpf.type_deducer import ctypes_to_ir
logger = logging.getLogger(__name__)
@dataclass
class LocalSymbol:
var: ir.AllocaInstr
ir_type: ir.Type
metadata: Any = None
def __iter__(self):
yield self.var
yield self.ir_type
yield self.metadata
def _is_helper_call(call_node):
"""Check if a call node is a BPF helper function call."""
if isinstance(call_node.func, ast.Name):
# Exclude print from requiring temps (handles f-strings differently)
func_name = call_node.func.id
return HelperHandlerRegistry.has_handler(func_name) and func_name != "print"
elif isinstance(call_node.func, ast.Attribute):
return HelperHandlerRegistry.has_handler(call_node.func.attr)
return False
def handle_assign_allocation(builder, stmt, local_sym_tab, structs_sym_tab):
"""Handle memory allocation for assignment statements."""
# Validate assignment
if len(stmt.targets) != 1:
logger.warning("Multi-target assignment not supported, skipping allocation")
return
target = stmt.targets[0]
# Skip non-name targets (e.g., struct field assignments)
if isinstance(target, ast.Attribute):
logger.debug(f"Struct field assignment to {target.attr}, no allocation needed")
return
if not isinstance(target, ast.Name):
logger.warning(f"Unsupported assignment target type: {type(target).__name__}")
return
var_name = target.id
rval = stmt.value
# Skip if already allocated
if var_name in local_sym_tab:
logger.debug(f"Variable {var_name} already allocated, skipping")
return
# Determine type and allocate based on rval
if isinstance(rval, ast.Call):
_allocate_for_call(builder, var_name, rval, local_sym_tab, structs_sym_tab)
elif isinstance(rval, ast.Constant):
_allocate_for_constant(builder, var_name, rval, local_sym_tab)
elif isinstance(rval, ast.BinOp):
_allocate_for_binop(builder, var_name, local_sym_tab)
else:
logger.warning(
f"Unsupported assignment value type for {var_name}: {type(rval).__name__}"
)
def _allocate_for_call(builder, var_name, rval, local_sym_tab, structs_sym_tab):
"""Allocate memory for variable assigned from a call."""
if isinstance(rval.func, ast.Name):
call_type = rval.func.id
# C type constructors
if call_type in ("c_int32", "c_int64", "c_uint32", "c_uint64"):
ir_type = ctypes_to_ir(call_type)
var = builder.alloca(ir_type, name=var_name)
var.align = ir_type.width // 8
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
logger.info(f"Pre-allocated {var_name} as {call_type}")
# Helper functions
elif HelperHandlerRegistry.has_handler(call_type):
ir_type = ir.IntType(64) # Assume i64 return type
var = builder.alloca(ir_type, name=var_name)
var.align = 8
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
logger.info(f"Pre-allocated {var_name} for helper {call_type}")
# Deref function
elif call_type == "deref":
ir_type = ir.IntType(64) # Assume i64 return type
var = builder.alloca(ir_type, name=var_name)
var.align = 8
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
logger.info(f"Pre-allocated {var_name} for deref")
# Struct constructors
elif call_type in structs_sym_tab:
struct_info = structs_sym_tab[call_type]
var = builder.alloca(struct_info.ir_type, name=var_name)
local_sym_tab[var_name] = LocalSymbol(var, struct_info.ir_type, call_type)
logger.info(f"Pre-allocated {var_name} for struct {call_type}")
else:
logger.warning(f"Unknown call type for allocation: {call_type}")
elif isinstance(rval.func, ast.Attribute):
# Map method calls - need double allocation for ptr handling
_allocate_for_map_method(builder, var_name, local_sym_tab)
else:
logger.warning(f"Unsupported call function type for {var_name}")
def _allocate_for_map_method(builder, var_name, local_sym_tab):
"""Allocate memory for variable assigned from map method (double alloc)."""
# Main variable (pointer to pointer)
ir_type = ir.PointerType(ir.IntType(64))
var = builder.alloca(ir_type, name=var_name)
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
# Temporary variable for computed values
tmp_ir_type = ir.IntType(64)
var_tmp = builder.alloca(tmp_ir_type, name=f"{var_name}_tmp")
local_sym_tab[f"{var_name}_tmp"] = LocalSymbol(var_tmp, tmp_ir_type)
logger.info(f"Pre-allocated {var_name} and {var_name}_tmp for map method")
def _allocate_for_constant(builder, var_name, rval, local_sym_tab):
"""Allocate memory for variable assigned from a constant."""
if isinstance(rval.value, bool):
ir_type = ir.IntType(1)
var = builder.alloca(ir_type, name=var_name)
var.align = 1
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
logger.info(f"Pre-allocated {var_name} as bool")
elif isinstance(rval.value, int):
ir_type = ir.IntType(64)
var = builder.alloca(ir_type, name=var_name)
var.align = 8
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
logger.info(f"Pre-allocated {var_name} as i64")
elif isinstance(rval.value, str):
ir_type = ir.PointerType(ir.IntType(8))
var = builder.alloca(ir_type, name=var_name)
var.align = 8
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
logger.info(f"Pre-allocated {var_name} as string")
else:
logger.warning(
f"Unsupported constant type for {var_name}: {type(rval.value).__name__}"
)
def _allocate_for_binop(builder, var_name, local_sym_tab):
"""Allocate memory for variable assigned from a binary operation."""
ir_type = ir.IntType(64) # Assume i64 result
var = builder.alloca(ir_type, name=var_name)
var.align = 8
local_sym_tab[var_name] = LocalSymbol(var, ir_type)
logger.info(f"Pre-allocated {var_name} for binop result")
def allocate_temp_pool(builder, max_temps, local_sym_tab):
"""Allocate the temporary scratch space pool for helper arguments."""
if max_temps == 0:
return
logger.info(f"Allocating temp pool of {max_temps} variables")
for i in range(max_temps):
temp_name = f"__helper_temp_{i}"
temp_var = builder.alloca(ir.IntType(64), name=temp_name)
temp_var.align = 8
local_sym_tab[temp_name] = LocalSymbol(temp_var, ir.IntType(64))

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@ -1,108 +0,0 @@
import ast
import logging
from llvmlite import ir
from pythonbpf.expr import eval_expr
logger = logging.getLogger(__name__)
def handle_struct_field_assignment(
func, module, builder, target, rval, local_sym_tab, map_sym_tab, structs_sym_tab
):
"""Handle struct field assignment (obj.field = value)."""
var_name = target.value.id
field_name = target.attr
if var_name not in local_sym_tab:
logger.error(f"Variable '{var_name}' not found in symbol table")
return
struct_type = local_sym_tab[var_name].metadata
struct_info = structs_sym_tab[struct_type]
if field_name not in struct_info.fields:
logger.error(f"Field '{field_name}' not found in struct '{struct_type}'")
return
# Get field pointer and evaluate value
field_ptr = struct_info.gep(builder, local_sym_tab[var_name].var, field_name)
val = eval_expr(
func, module, builder, rval, local_sym_tab, map_sym_tab, structs_sym_tab
)
if val is None:
logger.error(f"Failed to evaluate value for {var_name}.{field_name}")
return
# TODO: Handle string assignment to char array (not a priority)
field_type = struct_info.field_type(field_name)
if isinstance(field_type, ir.ArrayType) and val[1] == ir.PointerType(ir.IntType(8)):
logger.warning(
f"String to char array assignment not implemented for {var_name}.{field_name}"
)
return
# Store the value
builder.store(val[0], field_ptr)
logger.info(f"Assigned to struct field {var_name}.{field_name}")
def handle_variable_assignment(
func, module, builder, var_name, rval, local_sym_tab, map_sym_tab, structs_sym_tab
):
"""Handle single named variable assignment."""
if var_name not in local_sym_tab:
logger.error(f"Variable {var_name} not declared.")
return False
var_ptr = local_sym_tab[var_name].var
var_type = local_sym_tab[var_name].ir_type
# NOTE: Special case for struct initialization
if isinstance(rval, ast.Call) and isinstance(rval.func, ast.Name):
struct_name = rval.func.id
if struct_name in structs_sym_tab and len(rval.args) == 0:
struct_info = structs_sym_tab[struct_name]
ir_struct = struct_info.ir_type
builder.store(ir.Constant(ir_struct, None), var_ptr)
logger.info(f"Initialized struct {struct_name} for variable {var_name}")
return True
val_result = eval_expr(
func, module, builder, rval, local_sym_tab, map_sym_tab, structs_sym_tab
)
if val_result is None:
logger.error(f"Failed to evaluate value for {var_name}")
return False
val, val_type = val_result
logger.info(f"Evaluated value for {var_name}: {val} of type {val_type}, {var_type}")
if val_type != var_type:
if isinstance(val_type, ir.IntType) and isinstance(var_type, ir.IntType):
# Allow implicit int widening
if val_type.width < var_type.width:
val = builder.sext(val, var_type)
logger.info(f"Implicitly widened int for variable {var_name}")
elif val_type.width > var_type.width:
val = builder.trunc(val, var_type)
logger.info(f"Implicitly truncated int for variable {var_name}")
elif isinstance(val_type, ir.IntType) and isinstance(var_type, ir.PointerType):
# NOTE: This is assignment to a PTR_TO_MAP_VALUE_OR_NULL
logger.info(
f"Creating temporary variable for pointer assignment to {var_name}"
)
var_ptr_tmp = local_sym_tab[f"{var_name}_tmp"].var
builder.store(val, var_ptr_tmp)
val = var_ptr_tmp
else:
logger.error(
f"Type mismatch for variable {var_name}: {val_type} vs {var_type}"
)
return False
builder.store(val, var_ptr)
logger.info(f"Assigned value to variable {var_name}")
return True

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@ -1,110 +1,71 @@
import ast
from llvmlite import ir
from logging import Logger
import logging
from pythonbpf.expr import get_base_type_and_depth, deref_to_depth, eval_expr
logger: Logger = logging.getLogger(__name__)
def get_operand_value(
func, module, operand, builder, local_sym_tab, map_sym_tab, structs_sym_tab=None
):
"""Extract the value from an operand, handling variables and constants."""
logger.info(f"Getting operand value for: {ast.dump(operand)}")
if isinstance(operand, ast.Name):
if operand.id in local_sym_tab:
var = local_sym_tab[operand.id].var
var_type = var.type
base_type, depth = get_base_type_and_depth(var_type)
logger.info(f"var is {var}, base_type is {base_type}, depth is {depth}")
val = deref_to_depth(func, builder, var, depth)
return val
raise ValueError(f"Undefined variable: {operand.id}")
elif isinstance(operand, ast.Constant):
if isinstance(operand.value, int):
cst = ir.Constant(ir.IntType(64), int(operand.value))
return cst
raise TypeError(f"Unsupported constant type: {type(operand.value)}")
elif isinstance(operand, ast.BinOp):
res = handle_binary_op_impl(
func, module, operand, builder, local_sym_tab, map_sym_tab, structs_sym_tab
)
return res
def recursive_dereferencer(var, builder):
"""dereference until primitive type comes out"""
if var.type == ir.PointerType(ir.PointerType(ir.IntType(64))):
a = builder.load(var)
return recursive_dereferencer(a, builder)
elif var.type == ir.PointerType(ir.IntType(64)):
a = builder.load(var)
return recursive_dereferencer(a, builder)
elif var.type == ir.IntType(64):
return var
else:
res = eval_expr(
func, module, builder, operand, local_sym_tab, map_sym_tab, structs_sym_tab
)
if res is None:
raise ValueError(f"Failed to evaluate call expression: {operand}")
val, _ = res
logger.info(f"Evaluated expr to {val} of type {val.type}")
base_type, depth = get_base_type_and_depth(val.type)
if depth > 0:
val = deref_to_depth(func, builder, val, depth)
return val
raise TypeError(f"Unsupported operand type: {type(operand)}")
raise TypeError(f"Unsupported type for dereferencing: {var.type}")
def handle_binary_op_impl(
func, module, rval, builder, local_sym_tab, map_sym_tab, structs_sym_tab=None
):
def handle_binary_op(rval, module, builder, var_name, local_sym_tab, map_sym_tab, func):
print(module)
left = rval.left
right = rval.right
op = rval.op
left = get_operand_value(
func, module, rval.left, builder, local_sym_tab, map_sym_tab, structs_sym_tab
)
right = get_operand_value(
func, module, rval.right, builder, local_sym_tab, map_sym_tab, structs_sym_tab
)
logger.info(f"left is {left}, right is {right}, op is {op}")
# NOTE: Before doing the operation, if the operands are integers
# we always extend them to i64. The assignment to LHS will take
# care of truncation if needed.
if isinstance(left.type, ir.IntType) and left.type.width < 64:
left = builder.sext(left, ir.IntType(64))
if isinstance(right.type, ir.IntType) and right.type.width < 64:
right = builder.sext(right, ir.IntType(64))
# Handle left operand
if isinstance(left, ast.Name):
if left.id in local_sym_tab:
left = recursive_dereferencer(local_sym_tab[left.id][0], builder)
else:
raise SyntaxError(f"Undefined variable: {left.id}")
elif isinstance(left, ast.Constant):
left = ir.Constant(ir.IntType(64), left.value)
else:
raise SyntaxError("Unsupported left operand type")
# Map AST operation nodes to LLVM IR builder methods
op_map = {
ast.Add: builder.add,
ast.Sub: builder.sub,
ast.Mult: builder.mul,
ast.Div: builder.sdiv,
ast.Mod: builder.srem,
ast.LShift: builder.shl,
ast.RShift: builder.lshr,
ast.BitOr: builder.or_,
ast.BitXor: builder.xor,
ast.BitAnd: builder.and_,
ast.FloorDiv: builder.udiv,
}
if isinstance(right, ast.Name):
if right.id in local_sym_tab:
right = recursive_dereferencer(local_sym_tab[right.id][0], builder)
else:
raise SyntaxError(f"Undefined variable: {right.id}")
elif isinstance(right, ast.Constant):
right = ir.Constant(ir.IntType(64), right.value)
else:
raise SyntaxError("Unsupported right operand type")
if type(op) in op_map:
result = op_map[type(op)](left, right)
return result
print(f"left is {left}, right is {right}, op is {op}")
if isinstance(op, ast.Add):
builder.store(builder.add(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.Sub):
builder.store(builder.sub(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.Mult):
builder.store(builder.mul(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.Div):
builder.store(builder.sdiv(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.Mod):
builder.store(builder.srem(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.LShift):
builder.store(builder.shl(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.RShift):
builder.store(builder.lshr(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.BitOr):
builder.store(builder.or_(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.BitXor):
builder.store(builder.xor(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.BitAnd):
builder.store(builder.and_(left, right), local_sym_tab[var_name][0])
elif isinstance(op, ast.FloorDiv):
builder.store(builder.udiv(left, right), local_sym_tab[var_name][0])
else:
raise SyntaxError("Unsupported binary operation")
def handle_binary_op(
func,
module,
rval,
builder,
var_name,
local_sym_tab,
map_sym_tab,
structs_sym_tab=None,
):
result = handle_binary_op_impl(
func, module, rval, builder, local_sym_tab, map_sym_tab, structs_sym_tab
)
if var_name and var_name in local_sym_tab:
logger.info(
f"Storing result {result} into variable {local_sym_tab[var_name].var}"
)
builder.store(result, local_sym_tab[var_name].var)
return result, result.type

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@ -1,27 +1,19 @@
import ast
from llvmlite import ir
from .license_pass import license_processing
from .functions import func_proc
from .functions_pass import func_proc
from .maps import maps_proc
from .structs import structs_proc
from .globals_pass import (
globals_list_creation,
globals_processing,
populate_global_symbol_table,
)
from .debuginfo import DW_LANG_C11, DwarfBehaviorEnum, DebugInfoGenerator
from .globals_pass import globals_processing
from .debuginfo import DW_LANG_C11, DwarfBehaviorEnum
import os
import subprocess
import inspect
from pathlib import Path
from pylibbpf import BpfProgram
import tempfile
from logging import Logger
import logging
logger: Logger = logging.getLogger(__name__)
VERSION = "v0.1.4"
VERSION = "v0.1.3"
def find_bpf_chunks(tree):
@ -38,27 +30,21 @@ def find_bpf_chunks(tree):
def processor(source_code, filename, module):
tree = ast.parse(source_code, filename)
logger.debug(ast.dump(tree, indent=4))
print(ast.dump(tree, indent=4))
bpf_chunks = find_bpf_chunks(tree)
for func_node in bpf_chunks:
logger.info(f"Found BPF function/struct: {func_node.name}")
populate_global_symbol_table(tree, module)
license_processing(tree, module)
globals_processing(tree, module)
print(f"Found BPF function/struct: {func_node.name}")
structs_sym_tab = structs_proc(tree, module, bpf_chunks)
map_sym_tab = maps_proc(tree, module, bpf_chunks)
func_proc(tree, module, bpf_chunks, map_sym_tab, structs_sym_tab)
globals_list_creation(tree, module)
license_processing(tree, module)
globals_processing(tree, module)
def compile_to_ir(filename: str, output: str, loglevel=logging.INFO):
logging.basicConfig(
level=loglevel, format="%(asctime)s [%(levelname)s] %(name)s: %(message)s"
)
def compile_to_ir(filename: str, output: str):
with open(filename) as f:
source = f.read()
@ -67,17 +53,33 @@ def compile_to_ir(filename: str, output: str, loglevel=logging.INFO):
module.triple = "bpf"
if not hasattr(module, "_debug_compile_unit"):
debug_generator = DebugInfoGenerator(module)
debug_generator.generate_file_metadata(filename, os.path.dirname(filename))
debug_generator.generate_debug_cu(
DW_LANG_C11,
f"PythonBPF {VERSION}",
True, # TODO: This is probably not true
# TODO: add a global field here that keeps track of all the globals. Works without it, but I think it might
# be required for kprobes.
True,
module._file_metadata = module.add_debug_info(
"DIFile",
{ # type: ignore
"filename": filename,
"directory": os.path.dirname(filename),
},
)
module._debug_compile_unit = module.add_debug_info(
"DICompileUnit",
{ # type: ignore
"language": DW_LANG_C11,
"file": module._file_metadata, # type: ignore
"producer": f"PythonBPF {VERSION}",
"isOptimized": True, # TODO: This is probably not true
# TODO: add a global field here that keeps track of all the globals. Works without it, but I think it might
# be required for kprobes.
"runtimeVersion": 0,
"emissionKind": 1,
"splitDebugInlining": False,
"nameTableKind": 0,
},
is_distinct=True,
)
module.add_named_metadata("llvm.dbg.cu", module._debug_compile_unit) # type: ignore
processor(source, filename, module)
wchar_size = module.add_metadata(
@ -119,7 +121,7 @@ def compile_to_ir(filename: str, output: str, loglevel=logging.INFO):
module.add_named_metadata("llvm.ident", [f"PythonBPF {VERSION}"])
logger.info(f"IR written to {output}")
print(f"IR written to {output}")
with open(output, "w") as f:
f.write(f'source_filename = "{filename}"\n')
f.write(str(module))
@ -128,7 +130,7 @@ def compile_to_ir(filename: str, output: str, loglevel=logging.INFO):
return output
def compile(loglevel=logging.INFO) -> bool:
def compile() -> bool:
# Look one level up the stack to the caller of this function
caller_frame = inspect.stack()[1]
caller_file = Path(caller_frame.filename).resolve()
@ -137,9 +139,7 @@ def compile(loglevel=logging.INFO) -> bool:
o_file = caller_file.with_suffix(".o")
success = True
success = (
compile_to_ir(str(caller_file), str(ll_file), loglevel=loglevel) and success
)
success = compile_to_ir(str(caller_file), str(ll_file)) and success
success = bool(
subprocess.run(
@ -157,11 +157,11 @@ def compile(loglevel=logging.INFO) -> bool:
and success
)
logger.info(f"Object written to {o_file}")
print(f"Object written to {o_file}")
return success
def BPF(loglevel=logging.INFO) -> BpfProgram:
def BPF() -> BpfProgram:
caller_frame = inspect.stack()[1]
src = inspect.getsource(caller_frame.frame)
with tempfile.NamedTemporaryFile(
@ -174,7 +174,7 @@ def BPF(loglevel=logging.INFO) -> BpfProgram:
f.write(src)
f.flush()
source = f.name
compile_to_ir(source, str(inter.name), loglevel=loglevel)
compile_to_ir(source, str(inter.name))
subprocess.run(
[
"llc",

View File

@ -12,34 +12,6 @@ class DebugInfoGenerator:
self.module = module
self._type_cache = {} # Cache for common debug types
def generate_file_metadata(self, filename, dirname):
self.module._file_metadata = self.module.add_debug_info(
"DIFile",
{ # type: ignore
"filename": filename,
"directory": dirname,
},
)
def generate_debug_cu(
self, language, producer: str, is_optimized: bool, is_distinct: bool
):
self.module._debug_compile_unit = self.module.add_debug_info(
"DICompileUnit",
{ # type: ignore
"language": language,
"file": self.module._file_metadata, # type: ignore
"producer": producer,
"isOptimized": is_optimized,
"runtimeVersion": 0,
"emissionKind": 1,
"splitDebugInlining": False,
"nameTableKind": 0,
},
is_distinct=is_distinct,
)
self.module.add_named_metadata("llvm.dbg.cu", self.module._debug_compile_unit) # type: ignore
def get_basic_type(self, name: str, size: int, encoding: int) -> Any:
"""Get or create a basic type with caching"""
key = (name, size, encoding)

View File

@ -1,10 +0,0 @@
from .expr_pass import eval_expr, handle_expr
from .type_normalization import convert_to_bool, get_base_type_and_depth, deref_to_depth
__all__ = [
"eval_expr",
"handle_expr",
"convert_to_bool",
"get_base_type_and_depth",
"deref_to_depth",
]

View File

@ -1,461 +0,0 @@
import ast
from llvmlite import ir
from logging import Logger
import logging
from typing import Dict
from pythonbpf.type_deducer import ctypes_to_ir, is_ctypes
from .type_normalization import convert_to_bool, handle_comparator
logger: Logger = logging.getLogger(__name__)
def _handle_name_expr(expr: ast.Name, local_sym_tab: Dict, builder: ir.IRBuilder):
"""Handle ast.Name expressions."""
if expr.id in local_sym_tab:
var = local_sym_tab[expr.id].var
val = builder.load(var)
return val, local_sym_tab[expr.id].ir_type
else:
logger.info(f"Undefined variable {expr.id}")
return None
def _handle_constant_expr(expr: ast.Constant):
"""Handle ast.Constant expressions."""
if isinstance(expr.value, int) or isinstance(expr.value, bool):
return ir.Constant(ir.IntType(64), int(expr.value)), ir.IntType(64)
else:
logger.error(f"Unsupported constant type {ast.dump(expr)}")
return None
def _handle_attribute_expr(
expr: ast.Attribute,
local_sym_tab: Dict,
structs_sym_tab: Dict,
builder: ir.IRBuilder,
):
"""Handle ast.Attribute expressions for struct field access."""
if isinstance(expr.value, ast.Name):
var_name = expr.value.id
attr_name = expr.attr
if var_name in local_sym_tab:
var_ptr, var_type, var_metadata = local_sym_tab[var_name]
logger.info(f"Loading attribute {attr_name} from variable {var_name}")
logger.info(f"Variable type: {var_type}, Variable ptr: {var_ptr}")
metadata = structs_sym_tab[var_metadata]
if attr_name in metadata.fields:
gep = metadata.gep(builder, var_ptr, attr_name)
val = builder.load(gep)
field_type = metadata.field_type(attr_name)
return val, field_type
return None
def _handle_deref_call(expr: ast.Call, local_sym_tab: Dict, builder: ir.IRBuilder):
"""Handle deref function calls."""
logger.info(f"Handling deref {ast.dump(expr)}")
if len(expr.args) != 1:
logger.info("deref takes exactly one argument")
return None
arg = expr.args[0]
if (
isinstance(arg, ast.Call)
and isinstance(arg.func, ast.Name)
and arg.func.id == "deref"
):
logger.info("Multiple deref not supported")
return None
if isinstance(arg, ast.Name):
if arg.id in local_sym_tab:
arg_ptr = local_sym_tab[arg.id].var
else:
logger.info(f"Undefined variable {arg.id}")
return None
else:
logger.info("Unsupported argument type for deref")
return None
if arg_ptr is None:
logger.info("Failed to evaluate deref argument")
return None
# Load the value from pointer
val = builder.load(arg_ptr)
return val, local_sym_tab[arg.id].ir_type
def _handle_ctypes_call(
func,
module,
builder,
expr,
local_sym_tab,
map_sym_tab,
structs_sym_tab=None,
):
"""Handle ctypes type constructor calls."""
if len(expr.args) != 1:
logger.info("ctypes constructor takes exactly one argument")
return None
arg = expr.args[0]
val = eval_expr(
func,
module,
builder,
arg,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
if val is None:
logger.info("Failed to evaluate argument to ctypes constructor")
return None
call_type = expr.func.id
expected_type = ctypes_to_ir(call_type)
if val[1] != expected_type:
# NOTE: We are only considering casting to and from int types for now
if isinstance(val[1], ir.IntType) and isinstance(expected_type, ir.IntType):
if val[1].width < expected_type.width:
val = (builder.sext(val[0], expected_type), expected_type)
else:
val = (builder.trunc(val[0], expected_type), expected_type)
else:
raise ValueError(f"Type mismatch: expected {expected_type}, got {val[1]}")
return val
def _handle_compare(
func, module, builder, cond, local_sym_tab, map_sym_tab, structs_sym_tab=None
):
"""Handle ast.Compare expressions."""
if len(cond.ops) != 1 or len(cond.comparators) != 1:
logger.error("Only single comparisons are supported")
return None
lhs = eval_expr(
func,
module,
builder,
cond.left,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
rhs = eval_expr(
func,
module,
builder,
cond.comparators[0],
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
if lhs is None or rhs is None:
logger.error("Failed to evaluate comparison operands")
return None
lhs, _ = lhs
rhs, _ = rhs
return handle_comparator(func, builder, cond.ops[0], lhs, rhs)
def _handle_unary_op(
func,
module,
builder,
expr: ast.UnaryOp,
local_sym_tab,
map_sym_tab,
structs_sym_tab=None,
):
"""Handle ast.UnaryOp expressions."""
if not isinstance(expr.op, ast.Not) and not isinstance(expr.op, ast.USub):
logger.error("Only 'not' and '-' unary operators are supported")
return None
from pythonbpf.binary_ops import get_operand_value
operand = get_operand_value(
func, module, expr.operand, builder, local_sym_tab, map_sym_tab, structs_sym_tab
)
if operand is None:
logger.error("Failed to evaluate operand for unary operation")
return None
if isinstance(expr.op, ast.Not):
true_const = ir.Constant(ir.IntType(1), 1)
result = builder.xor(convert_to_bool(builder, operand), true_const)
return result, ir.IntType(1)
elif isinstance(expr.op, ast.USub):
# Multiply by -1
neg_one = ir.Constant(ir.IntType(64), -1)
result = builder.mul(operand, neg_one)
return result, ir.IntType(64)
def _handle_and_op(func, builder, expr, local_sym_tab, map_sym_tab, structs_sym_tab):
"""Handle `and` boolean operations."""
logger.debug(f"Handling 'and' operator with {len(expr.values)} operands")
merge_block = func.append_basic_block(name="and.merge")
false_block = func.append_basic_block(name="and.false")
incoming_values = []
for i, value in enumerate(expr.values):
is_last = i == len(expr.values) - 1
# Evaluate current operand
operand_result = eval_expr(
func, None, builder, value, local_sym_tab, map_sym_tab, structs_sym_tab
)
if operand_result is None:
logger.error(f"Failed to evaluate operand {i} in 'and' expression")
return None
operand_val, operand_type = operand_result
# Convert to boolean if needed
operand_bool = convert_to_bool(builder, operand_val)
current_block = builder.block
if is_last:
# Last operand: result is this value
builder.branch(merge_block)
incoming_values.append((operand_bool, current_block))
else:
# Not last: check if true, continue or short-circuit
next_check = func.append_basic_block(name=f"and.check_{i + 1}")
builder.cbranch(operand_bool, next_check, false_block)
builder.position_at_end(next_check)
# False block: short-circuit with false
builder.position_at_end(false_block)
builder.branch(merge_block)
false_value = ir.Constant(ir.IntType(1), 0)
incoming_values.append((false_value, false_block))
# Merge block: phi node
builder.position_at_end(merge_block)
phi = builder.phi(ir.IntType(1), name="and.result")
for val, block in incoming_values:
phi.add_incoming(val, block)
logger.debug(f"Generated 'and' with {len(incoming_values)} incoming values")
return phi, ir.IntType(1)
def _handle_or_op(func, builder, expr, local_sym_tab, map_sym_tab, structs_sym_tab):
"""Handle `or` boolean operations."""
logger.debug(f"Handling 'or' operator with {len(expr.values)} operands")
merge_block = func.append_basic_block(name="or.merge")
true_block = func.append_basic_block(name="or.true")
incoming_values = []
for i, value in enumerate(expr.values):
is_last = i == len(expr.values) - 1
# Evaluate current operand
operand_result = eval_expr(
func, None, builder, value, local_sym_tab, map_sym_tab, structs_sym_tab
)
if operand_result is None:
logger.error(f"Failed to evaluate operand {i} in 'or' expression")
return None
operand_val, operand_type = operand_result
# Convert to boolean if needed
operand_bool = convert_to_bool(builder, operand_val)
current_block = builder.block
if is_last:
# Last operand: result is this value
builder.branch(merge_block)
incoming_values.append((operand_bool, current_block))
else:
# Not last: check if false, continue or short-circuit
next_check = func.append_basic_block(name=f"or.check_{i + 1}")
builder.cbranch(operand_bool, true_block, next_check)
builder.position_at_end(next_check)
# True block: short-circuit with true
builder.position_at_end(true_block)
builder.branch(merge_block)
true_value = ir.Constant(ir.IntType(1), 1)
incoming_values.append((true_value, true_block))
# Merge block: phi node
builder.position_at_end(merge_block)
phi = builder.phi(ir.IntType(1), name="or.result")
for val, block in incoming_values:
phi.add_incoming(val, block)
logger.debug(f"Generated 'or' with {len(incoming_values)} incoming values")
return phi, ir.IntType(1)
def _handle_boolean_op(
func,
module,
builder,
expr: ast.BoolOp,
local_sym_tab,
map_sym_tab,
structs_sym_tab=None,
):
"""Handle `and` and `or` boolean operations."""
if isinstance(expr.op, ast.And):
return _handle_and_op(
func, builder, expr, local_sym_tab, map_sym_tab, structs_sym_tab
)
elif isinstance(expr.op, ast.Or):
return _handle_or_op(
func, builder, expr, local_sym_tab, map_sym_tab, structs_sym_tab
)
else:
logger.error(f"Unsupported boolean operator: {type(expr.op).__name__}")
return None
def eval_expr(
func,
module,
builder,
expr,
local_sym_tab,
map_sym_tab,
structs_sym_tab=None,
):
logger.info(f"Evaluating expression: {ast.dump(expr)}")
if isinstance(expr, ast.Name):
return _handle_name_expr(expr, local_sym_tab, builder)
elif isinstance(expr, ast.Constant):
return _handle_constant_expr(expr)
elif isinstance(expr, ast.Call):
if isinstance(expr.func, ast.Name) and expr.func.id == "deref":
return _handle_deref_call(expr, local_sym_tab, builder)
if isinstance(expr.func, ast.Name) and is_ctypes(expr.func.id):
return _handle_ctypes_call(
func,
module,
builder,
expr,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
# delayed import to avoid circular dependency
from pythonbpf.helper import HelperHandlerRegistry, handle_helper_call
if isinstance(expr.func, ast.Name) and HelperHandlerRegistry.has_handler(
expr.func.id
):
return handle_helper_call(
expr,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
elif isinstance(expr.func, ast.Attribute):
logger.info(f"Handling method call: {ast.dump(expr.func)}")
if isinstance(expr.func.value, ast.Call) and isinstance(
expr.func.value.func, ast.Name
):
method_name = expr.func.attr
if HelperHandlerRegistry.has_handler(method_name):
return handle_helper_call(
expr,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
elif isinstance(expr.func.value, ast.Name):
obj_name = expr.func.value.id
method_name = expr.func.attr
if obj_name in map_sym_tab:
if HelperHandlerRegistry.has_handler(method_name):
return handle_helper_call(
expr,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
elif isinstance(expr, ast.Attribute):
return _handle_attribute_expr(expr, local_sym_tab, structs_sym_tab, builder)
elif isinstance(expr, ast.BinOp):
from pythonbpf.binary_ops import handle_binary_op
return handle_binary_op(
func,
module,
expr,
builder,
None,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
elif isinstance(expr, ast.Compare):
return _handle_compare(
func, module, builder, expr, local_sym_tab, map_sym_tab, structs_sym_tab
)
elif isinstance(expr, ast.UnaryOp):
return _handle_unary_op(
func, module, builder, expr, local_sym_tab, map_sym_tab, structs_sym_tab
)
elif isinstance(expr, ast.BoolOp):
return _handle_boolean_op(
func, module, builder, expr, local_sym_tab, map_sym_tab, structs_sym_tab
)
logger.info("Unsupported expression evaluation")
return None
def handle_expr(
func,
module,
builder,
expr,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
):
"""Handle expression statements in the function body."""
logger.info(f"Handling expression: {ast.dump(expr)}")
call = expr.value
if isinstance(call, ast.Call):
eval_expr(
func,
module,
builder,
call,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
else:
logger.info("Unsupported expression type")

View File

@ -1,128 +0,0 @@
from llvmlite import ir
import logging
import ast
logger = logging.getLogger(__name__)
COMPARISON_OPS = {
ast.Eq: "==",
ast.NotEq: "!=",
ast.Lt: "<",
ast.LtE: "<=",
ast.Gt: ">",
ast.GtE: ">=",
ast.Is: "==",
ast.IsNot: "!=",
}
def get_base_type_and_depth(ir_type):
"""Get the base type for pointer types."""
cur_type = ir_type
depth = 0
while isinstance(cur_type, ir.PointerType):
depth += 1
cur_type = cur_type.pointee
return cur_type, depth
def deref_to_depth(func, builder, val, target_depth):
"""Dereference a pointer to a certain depth."""
cur_val = val
cur_type = val.type
for depth in range(target_depth):
if not isinstance(val.type, ir.PointerType):
logger.error("Cannot dereference further, non-pointer type")
return None
# dereference with null check
pointee_type = cur_type.pointee
null_check_block = builder.block
not_null_block = func.append_basic_block(name=f"deref_not_null_{depth}")
merge_block = func.append_basic_block(name=f"deref_merge_{depth}")
null_ptr = ir.Constant(cur_type, None)
is_not_null = builder.icmp_signed("!=", cur_val, null_ptr)
logger.debug(f"Inserted null check for pointer at depth {depth}")
builder.cbranch(is_not_null, not_null_block, merge_block)
builder.position_at_end(not_null_block)
dereferenced_val = builder.load(cur_val)
logger.debug(f"Dereferenced to depth {depth - 1}, type: {pointee_type}")
builder.branch(merge_block)
builder.position_at_end(merge_block)
phi = builder.phi(pointee_type, name=f"deref_result_{depth}")
zero_value = (
ir.Constant(pointee_type, 0)
if isinstance(pointee_type, ir.IntType)
else ir.Constant(pointee_type, None)
)
phi.add_incoming(zero_value, null_check_block)
phi.add_incoming(dereferenced_val, not_null_block)
# Continue with phi result
cur_val = phi
cur_type = pointee_type
return cur_val
def _normalize_types(func, builder, lhs, rhs):
"""Normalize types for comparison."""
logger.info(f"Normalizing types: {lhs.type} vs {rhs.type}")
if isinstance(lhs.type, ir.IntType) and isinstance(rhs.type, ir.IntType):
if lhs.type.width < rhs.type.width:
lhs = builder.sext(lhs, rhs.type)
else:
rhs = builder.sext(rhs, lhs.type)
return lhs, rhs
elif not isinstance(lhs.type, ir.PointerType) and not isinstance(
rhs.type, ir.PointerType
):
logger.error(f"Type mismatch: {lhs.type} vs {rhs.type}")
return None, None
else:
lhs_base, lhs_depth = get_base_type_and_depth(lhs.type)
rhs_base, rhs_depth = get_base_type_and_depth(rhs.type)
if lhs_base == rhs_base:
if lhs_depth < rhs_depth:
rhs = deref_to_depth(func, builder, rhs, rhs_depth - lhs_depth)
elif rhs_depth < lhs_depth:
lhs = deref_to_depth(func, builder, lhs, lhs_depth - rhs_depth)
return _normalize_types(func, builder, lhs, rhs)
def convert_to_bool(builder, val):
"""Convert a value to boolean."""
if val.type == ir.IntType(1):
return val
if isinstance(val.type, ir.PointerType):
zero = ir.Constant(val.type, None)
else:
zero = ir.Constant(val.type, 0)
return builder.icmp_signed("!=", val, zero)
def handle_comparator(func, builder, op, lhs, rhs):
"""Handle comparison operations."""
if lhs.type != rhs.type:
lhs, rhs = _normalize_types(func, builder, lhs, rhs)
if lhs is None or rhs is None:
return None
if type(op) not in COMPARISON_OPS:
logger.error(f"Unsupported comparison operator: {type(op)}")
return None
predicate = COMPARISON_OPS[type(op)]
result = builder.icmp_signed(predicate, lhs, rhs)
logger.debug(f"Comparison result: {result}")
return result, ir.IntType(1)

155
pythonbpf/expr_pass.py Normal file
View File

@ -0,0 +1,155 @@
import ast
from llvmlite import ir
def eval_expr(
func,
module,
builder,
expr,
local_sym_tab,
map_sym_tab,
structs_sym_tab=None,
local_var_metadata=None,
):
print(f"Evaluating expression: {ast.dump(expr)}")
print(local_var_metadata)
if isinstance(expr, ast.Name):
if expr.id in local_sym_tab:
var = local_sym_tab[expr.id][0]
val = builder.load(var)
return val, local_sym_tab[expr.id][1] # return value and type
else:
print(f"Undefined variable {expr.id}")
return None
elif isinstance(expr, ast.Constant):
if isinstance(expr.value, int):
return ir.Constant(ir.IntType(64), expr.value), ir.IntType(64)
elif isinstance(expr.value, bool):
return ir.Constant(ir.IntType(1), int(expr.value)), ir.IntType(1)
else:
print("Unsupported constant type")
return None
elif isinstance(expr, ast.Call):
# delayed import to avoid circular dependency
from pythonbpf.helper import HelperHandlerRegistry, handle_helper_call
if isinstance(expr.func, ast.Name):
# check deref
if expr.func.id == "deref":
print(f"Handling deref {ast.dump(expr)}")
if len(expr.args) != 1:
print("deref takes exactly one argument")
return None
arg = expr.args[0]
if (
isinstance(arg, ast.Call)
and isinstance(arg.func, ast.Name)
and arg.func.id == "deref"
):
print("Multiple deref not supported")
return None
if isinstance(arg, ast.Name):
if arg.id in local_sym_tab:
arg = local_sym_tab[arg.id][0]
else:
print(f"Undefined variable {arg.id}")
return None
if arg is None:
print("Failed to evaluate deref argument")
return None
# Since we are handling only name case, directly take type from sym tab
val = builder.load(arg)
return val, local_sym_tab[expr.args[0].id][1]
# check for helpers
if HelperHandlerRegistry.has_handler(expr.func.id):
return handle_helper_call(
expr,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
)
elif isinstance(expr.func, ast.Attribute):
print(f"Handling method call: {ast.dump(expr.func)}")
if isinstance(expr.func.value, ast.Call) and isinstance(
expr.func.value.func, ast.Name
):
method_name = expr.func.attr
if HelperHandlerRegistry.has_handler(method_name):
return handle_helper_call(
expr,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
)
elif isinstance(expr.func.value, ast.Name):
obj_name = expr.func.value.id
method_name = expr.func.attr
if obj_name in map_sym_tab:
if HelperHandlerRegistry.has_handler(method_name):
return handle_helper_call(
expr,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
)
elif isinstance(expr, ast.Attribute):
if isinstance(expr.value, ast.Name):
var_name = expr.value.id
attr_name = expr.attr
if var_name in local_sym_tab:
var_ptr, var_type = local_sym_tab[var_name]
print(f"Loading attribute " f"{attr_name} from variable {var_name}")
print(f"Variable type: {var_type}, Variable ptr: {var_ptr}")
print(local_var_metadata)
if local_var_metadata and var_name in local_var_metadata:
metadata = structs_sym_tab[local_var_metadata[var_name]]
if attr_name in metadata.fields:
gep = metadata.gep(builder, var_ptr, attr_name)
val = builder.load(gep)
field_type = metadata.field_type(attr_name)
return val, field_type
print("Unsupported expression evaluation")
return None
def handle_expr(
func,
module,
builder,
expr,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
):
"""Handle expression statements in the function body."""
print(f"Handling expression: {ast.dump(expr)}")
print(local_var_metadata)
call = expr.value
if isinstance(call, ast.Call):
eval_expr(
func,
module,
builder,
call,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
)
else:
print("Unsupported expression type")

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@ -1,3 +0,0 @@
from .functions_pass import func_proc
__all__ = ["func_proc"]

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@ -1,22 +0,0 @@
from typing import Dict
class StatementHandlerRegistry:
"""Registry for statement handlers."""
_handlers: Dict = {}
@classmethod
def register(cls, stmt_type):
"""Register a handler for a specific statement type."""
def decorator(handler):
cls._handlers[stmt_type] = handler
return handler
return decorator
@classmethod
def __getitem__(cls, stmt_type):
"""Get the handler for a specific statement type."""
return cls._handlers.get(stmt_type, None)

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@ -1,521 +0,0 @@
from llvmlite import ir
import ast
import logging
from pythonbpf.helper import (
HelperHandlerRegistry,
reset_scratch_pool,
)
from pythonbpf.type_deducer import ctypes_to_ir
from pythonbpf.expr import eval_expr, handle_expr, convert_to_bool
from pythonbpf.assign_pass import (
handle_variable_assignment,
handle_struct_field_assignment,
)
from pythonbpf.allocation_pass import handle_assign_allocation, allocate_temp_pool
from .return_utils import _handle_none_return, _handle_xdp_return, _is_xdp_name
logger = logging.getLogger(__name__)
def get_probe_string(func_node):
"""Extract the probe string from the decorator of the function node."""
# TODO: right now we have the whole string in the section decorator
# But later we can implement typed tuples for tracepoints and kprobes
# For helper functions, we return "helper"
for decorator in func_node.decorator_list:
if isinstance(decorator, ast.Name) and decorator.id == "bpfglobal":
return None
if isinstance(decorator, ast.Call) and isinstance(decorator.func, ast.Name):
if decorator.func.id == "section" and len(decorator.args) == 1:
arg = decorator.args[0]
if isinstance(arg, ast.Constant) and isinstance(arg.value, str):
return arg.value
return "helper"
def handle_assign(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab
):
"""Handle assignment statements in the function body."""
# TODO: Support this later
# GH #37
if len(stmt.targets) != 1:
logger.error("Multi-target assignment is not supported for now")
return
target = stmt.targets[0]
rval = stmt.value
if isinstance(target, ast.Name):
# NOTE: Simple variable assignment case: x = 5
var_name = target.id
result = handle_variable_assignment(
func,
module,
builder,
var_name,
rval,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
if not result:
logger.error(f"Failed to handle assignment to {var_name}")
return
if isinstance(target, ast.Attribute):
# NOTE: Struct field assignment case: pkt.field = value
handle_struct_field_assignment(
func,
module,
builder,
target,
rval,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
return
# Unsupported target type
logger.error(f"Unsupported assignment target: {ast.dump(target)}")
def handle_cond(
func, module, builder, cond, local_sym_tab, map_sym_tab, structs_sym_tab=None
):
val = eval_expr(
func, module, builder, cond, local_sym_tab, map_sym_tab, structs_sym_tab
)[0]
return convert_to_bool(builder, val)
def handle_if(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab=None
):
"""Handle if statements in the function body."""
logger.info("Handling if statement")
# start = builder.block.parent
then_block = func.append_basic_block(name="if.then")
merge_block = func.append_basic_block(name="if.end")
if stmt.orelse:
else_block = func.append_basic_block(name="if.else")
else:
else_block = None
cond = handle_cond(
func, module, builder, stmt.test, local_sym_tab, map_sym_tab, structs_sym_tab
)
if else_block:
builder.cbranch(cond, then_block, else_block)
else:
builder.cbranch(cond, then_block, merge_block)
builder.position_at_end(then_block)
for s in stmt.body:
process_stmt(
func, module, builder, s, local_sym_tab, map_sym_tab, structs_sym_tab, False
)
if not builder.block.is_terminated:
builder.branch(merge_block)
if else_block:
builder.position_at_end(else_block)
for s in stmt.orelse:
process_stmt(
func,
module,
builder,
s,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
False,
)
if not builder.block.is_terminated:
builder.branch(merge_block)
builder.position_at_end(merge_block)
def handle_return(builder, stmt, local_sym_tab, ret_type):
logger.info(f"Handling return statement: {ast.dump(stmt)}")
if stmt.value is None:
return _handle_none_return(builder)
elif isinstance(stmt.value, ast.Name) and _is_xdp_name(stmt.value.id):
return _handle_xdp_return(stmt, builder, ret_type)
else:
val = eval_expr(
func=None,
module=None,
builder=builder,
expr=stmt.value,
local_sym_tab=local_sym_tab,
map_sym_tab={},
structs_sym_tab={},
)
logger.info(f"Evaluated return expression to {val}")
builder.ret(val[0])
return True
def process_stmt(
func,
module,
builder,
stmt,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
did_return,
ret_type=ir.IntType(64),
):
logger.info(f"Processing statement: {ast.dump(stmt)}")
reset_scratch_pool()
if isinstance(stmt, ast.Expr):
handle_expr(
func,
module,
builder,
stmt,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
elif isinstance(stmt, ast.Assign):
handle_assign(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab
)
elif isinstance(stmt, ast.AugAssign):
raise SyntaxError("Augmented assignment not supported")
elif isinstance(stmt, ast.If):
handle_if(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab
)
elif isinstance(stmt, ast.Return):
did_return = handle_return(
builder,
stmt,
local_sym_tab,
ret_type,
)
return did_return
def handle_if_allocation(
module, builder, stmt, func, ret_type, map_sym_tab, local_sym_tab, structs_sym_tab
):
"""Recursively handle allocations in if/else branches."""
if stmt.body:
allocate_mem(
module,
builder,
stmt.body,
func,
ret_type,
map_sym_tab,
local_sym_tab,
structs_sym_tab,
)
if stmt.orelse:
allocate_mem(
module,
builder,
stmt.orelse,
func,
ret_type,
map_sym_tab,
local_sym_tab,
structs_sym_tab,
)
def count_temps_in_call(call_node, local_sym_tab):
"""Count the number of temporary variables needed for a function call."""
count = 0
is_helper = False
# NOTE: We exclude print calls for now
if isinstance(call_node.func, ast.Name):
if (
HelperHandlerRegistry.has_handler(call_node.func.id)
and call_node.func.id != "print"
):
is_helper = True
elif isinstance(call_node.func, ast.Attribute):
if HelperHandlerRegistry.has_handler(call_node.func.attr):
is_helper = True
if not is_helper:
return 0
for arg in call_node.args:
# NOTE: Count all non-name arguments
# For struct fields, if it is being passed as an argument,
# The struct object should already exist in the local_sym_tab
if not isinstance(arg, ast.Name) and not (
isinstance(arg, ast.Attribute) and arg.value.id in local_sym_tab
):
count += 1
return count
def allocate_mem(
module, builder, body, func, ret_type, map_sym_tab, local_sym_tab, structs_sym_tab
):
max_temps_needed = 0
def update_max_temps_for_stmt(stmt):
nonlocal max_temps_needed
temps_needed = 0
if isinstance(stmt, ast.If):
for s in stmt.body:
update_max_temps_for_stmt(s)
for s in stmt.orelse:
update_max_temps_for_stmt(s)
return
for node in ast.walk(stmt):
if isinstance(node, ast.Call):
temps_needed += count_temps_in_call(node, local_sym_tab)
max_temps_needed = max(max_temps_needed, temps_needed)
for stmt in body:
update_max_temps_for_stmt(stmt)
# Handle allocations
if isinstance(stmt, ast.If):
handle_if_allocation(
module,
builder,
stmt,
func,
ret_type,
map_sym_tab,
local_sym_tab,
structs_sym_tab,
)
elif isinstance(stmt, ast.Assign):
handle_assign_allocation(builder, stmt, local_sym_tab, structs_sym_tab)
allocate_temp_pool(builder, max_temps_needed, local_sym_tab)
return local_sym_tab
def process_func_body(
module, builder, func_node, func, ret_type, map_sym_tab, structs_sym_tab
):
"""Process the body of a bpf function"""
# TODO: A lot. We just have print -> bpf_trace_printk for now
did_return = False
local_sym_tab = {}
# pre-allocate dynamic variables
local_sym_tab = allocate_mem(
module,
builder,
func_node.body,
func,
ret_type,
map_sym_tab,
local_sym_tab,
structs_sym_tab,
)
logger.info(f"Local symbol table: {local_sym_tab.keys()}")
for stmt in func_node.body:
did_return = process_stmt(
func,
module,
builder,
stmt,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
did_return,
ret_type,
)
if not did_return:
builder.ret(ir.Constant(ir.IntType(64), 0))
def process_bpf_chunk(func_node, module, return_type, map_sym_tab, structs_sym_tab):
"""Process a single BPF chunk (function) and emit corresponding LLVM IR."""
func_name = func_node.name
ret_type = return_type
# TODO: parse parameters
param_types = []
if func_node.args.args:
# Assume first arg to be ctx
param_types.append(ir.PointerType())
func_ty = ir.FunctionType(ret_type, param_types)
func = ir.Function(module, func_ty, func_name)
func.linkage = "dso_local"
func.attributes.add("nounwind")
func.attributes.add("noinline")
func.attributes.add("optnone")
if func_node.args.args:
# Only look at the first argument for now
param = func.args[0]
param.add_attribute("nocapture")
probe_string = get_probe_string(func_node)
if probe_string is not None:
func.section = probe_string
block = func.append_basic_block(name="entry")
builder = ir.IRBuilder(block)
process_func_body(
module, builder, func_node, func, ret_type, map_sym_tab, structs_sym_tab
)
return func
def func_proc(tree, module, chunks, map_sym_tab, structs_sym_tab):
for func_node in chunks:
is_global = False
for decorator in func_node.decorator_list:
if isinstance(decorator, ast.Name) and decorator.id in (
"map",
"bpfglobal",
"struct",
):
is_global = True
break
if is_global:
continue
func_type = get_probe_string(func_node)
logger.info(f"Found probe_string of {func_node.name}: {func_type}")
process_bpf_chunk(
func_node,
module,
ctypes_to_ir(infer_return_type(func_node)),
map_sym_tab,
structs_sym_tab,
)
def infer_return_type(func_node: ast.FunctionDef):
if not isinstance(func_node, (ast.FunctionDef, ast.AsyncFunctionDef)):
raise TypeError("Expected ast.FunctionDef")
if func_node.returns is not None:
try:
return ast.unparse(func_node.returns)
except Exception:
node = func_node.returns
if isinstance(node, ast.Name):
return node.id
if isinstance(node, ast.Attribute):
return getattr(node, "attr", type(node).__name__)
try:
return str(node)
except Exception:
return type(node).__name__
found_type = None
def _expr_type(e):
if e is None:
return "None"
if isinstance(e, ast.Constant):
return type(e.value).__name__
if isinstance(e, ast.Name):
return e.id
if isinstance(e, ast.Call):
f = e.func
if isinstance(f, ast.Name):
return f.id
if isinstance(f, ast.Attribute):
try:
return ast.unparse(f)
except Exception:
return getattr(f, "attr", type(f).__name__)
try:
return ast.unparse(f)
except Exception:
return type(f).__name__
if isinstance(e, ast.Attribute):
try:
return ast.unparse(e)
except Exception:
return getattr(e, "attr", type(e).__name__)
try:
return ast.unparse(e)
except Exception:
return type(e).__name__
for walked_node in ast.walk(func_node):
if isinstance(walked_node, ast.Return):
t = _expr_type(walked_node.value)
if found_type is None:
found_type = t
elif found_type != t:
raise ValueError(f"Conflicting return types: {found_type} vs {t}")
return found_type or "None"
# For string assignment to fixed-size arrays
def assign_string_to_array(builder, target_array_ptr, source_string_ptr, array_length):
"""
Copy a string (i8*) to a fixed-size array ([N x i8]*)
"""
# Create a loop to copy characters one by one
# entry_block = builder.block
copy_block = builder.append_basic_block("copy_char")
end_block = builder.append_basic_block("copy_end")
# Create loop counter
i = builder.alloca(ir.IntType(32))
builder.store(ir.Constant(ir.IntType(32), 0), i)
# Start the loop
builder.branch(copy_block)
# Copy loop
builder.position_at_end(copy_block)
idx = builder.load(i)
in_bounds = builder.icmp_unsigned(
"<", idx, ir.Constant(ir.IntType(32), array_length)
)
builder.cbranch(in_bounds, copy_block, end_block)
with builder.if_then(in_bounds):
# Load character from source
src_ptr = builder.gep(source_string_ptr, [idx])
char = builder.load(src_ptr)
# Store character in target
dst_ptr = builder.gep(target_array_ptr, [ir.Constant(ir.IntType(32), 0), idx])
builder.store(char, dst_ptr)
# Increment counter
next_idx = builder.add(idx, ir.Constant(ir.IntType(32), 1))
builder.store(next_idx, i)
builder.position_at_end(end_block)
# Ensure null termination
last_idx = ir.Constant(ir.IntType(32), array_length - 1)
null_ptr = builder.gep(target_array_ptr, [ir.Constant(ir.IntType(32), 0), last_idx])
builder.store(ir.Constant(ir.IntType(8), 0), null_ptr)

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@ -1,45 +0,0 @@
import logging
import ast
from llvmlite import ir
logger: logging.Logger = logging.getLogger(__name__)
XDP_ACTIONS = {
"XDP_ABORTED": 0,
"XDP_DROP": 1,
"XDP_PASS": 2,
"XDP_TX": 3,
"XDP_REDIRECT": 4,
}
def _handle_none_return(builder) -> bool:
"""Handle return or return None -> returns 0."""
builder.ret(ir.Constant(ir.IntType(64), 0))
logger.debug("Generated default return: 0")
return True
def _is_xdp_name(name: str) -> bool:
"""Check if a name is an XDP action"""
return name in XDP_ACTIONS
def _handle_xdp_return(stmt: ast.Return, builder, ret_type) -> bool:
"""Handle XDP returns"""
if not isinstance(stmt.value, ast.Name):
return False
action_name = stmt.value.id
if action_name not in XDP_ACTIONS:
raise ValueError(
f"Unknown XDP action: {action_name}. Available: {XDP_ACTIONS.keys()}"
)
return False
value = XDP_ACTIONS[action_name]
builder.ret(ir.Constant(ret_type, value))
logger.debug(f"Generated XDP action return: {action_name} = {value}")
return True

714
pythonbpf/functions_pass.py Normal file
View File

@ -0,0 +1,714 @@
from llvmlite import ir
import ast
from typing import Any
from .helper import HelperHandlerRegistry, handle_helper_call
from .type_deducer import ctypes_to_ir
from .binary_ops import handle_binary_op
from .expr_pass import eval_expr, handle_expr
local_var_metadata: dict[str | Any, Any] = {}
def get_probe_string(func_node):
"""Extract the probe string from the decorator of the function node."""
# TODO: right now we have the whole string in the section decorator
# But later we can implement typed tuples for tracepoints and kprobes
# For helper functions, we return "helper"
for decorator in func_node.decorator_list:
if isinstance(decorator, ast.Name) and decorator.id == "bpfglobal":
return None
if isinstance(decorator, ast.Call) and isinstance(decorator.func, ast.Name):
if decorator.func.id == "section" and len(decorator.args) == 1:
arg = decorator.args[0]
if isinstance(arg, ast.Constant) and isinstance(arg.value, str):
return arg.value
return "helper"
def handle_assign(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab
):
"""Handle assignment statements in the function body."""
if len(stmt.targets) != 1:
print("Unsupported multiassignment")
return
num_types = ("c_int32", "c_int64", "c_uint32", "c_uint64")
target = stmt.targets[0]
print(f"Handling assignment to {ast.dump(target)}")
if not isinstance(target, ast.Name) and not isinstance(target, ast.Attribute):
print("Unsupported assignment target")
return
var_name = target.id if isinstance(target, ast.Name) else target.value.id
rval = stmt.value
if isinstance(target, ast.Attribute):
# struct field assignment
field_name = target.attr
if var_name in local_sym_tab and var_name in local_var_metadata:
struct_type = local_var_metadata[var_name]
struct_info = structs_sym_tab[struct_type]
if field_name in struct_info.fields:
field_ptr = struct_info.gep(
builder, local_sym_tab[var_name][0], field_name
)
val = eval_expr(
func,
module,
builder,
rval,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
if isinstance(struct_info.field_type(field_name), ir.ArrayType) and val[
1
] == ir.PointerType(ir.IntType(8)):
# TODO: Figure it out, not a priority rn
# Special case for string assignment to char array
# str_len = struct_info["field_types"][field_idx].count
# assign_string_to_array(builder, field_ptr, val[0], str_len)
# print(f"Assigned to struct field {var_name}.{field_name}")
pass
if val is None:
print("Failed to evaluate struct field assignment")
return
print(field_ptr)
builder.store(val[0], field_ptr)
print(f"Assigned to struct field {var_name}.{field_name}")
return
elif isinstance(rval, ast.Constant):
if isinstance(rval.value, bool):
if rval.value:
builder.store(ir.Constant(ir.IntType(1), 1), local_sym_tab[var_name][0])
else:
builder.store(ir.Constant(ir.IntType(1), 0), local_sym_tab[var_name][0])
print(f"Assigned constant {rval.value} to {var_name}")
elif isinstance(rval.value, int):
# Assume c_int64 for now
# var = builder.alloca(ir.IntType(64), name=var_name)
# var.align = 8
builder.store(
ir.Constant(ir.IntType(64), rval.value), local_sym_tab[var_name][0]
)
# local_sym_tab[var_name] = var
print(f"Assigned constant {rval.value} to {var_name}")
elif isinstance(rval.value, str):
str_val = rval.value.encode("utf-8") + b"\x00"
str_const = ir.Constant(
ir.ArrayType(ir.IntType(8), len(str_val)), bytearray(str_val)
)
global_str = ir.GlobalVariable(
module, str_const.type, name=f"{var_name}_str"
)
global_str.linkage = "internal"
global_str.global_constant = True
global_str.initializer = str_const
str_ptr = builder.bitcast(global_str, ir.PointerType(ir.IntType(8)))
builder.store(str_ptr, local_sym_tab[var_name][0])
print(f"Assigned string constant '{rval.value}' to {var_name}")
else:
print("Unsupported constant type")
elif isinstance(rval, ast.Call):
if isinstance(rval.func, ast.Name):
call_type = rval.func.id
print(f"Assignment call type: {call_type}")
if (
call_type in num_types
and len(rval.args) == 1
and isinstance(rval.args[0], ast.Constant)
and isinstance(rval.args[0].value, int)
):
ir_type = ctypes_to_ir(call_type)
# var = builder.alloca(ir_type, name=var_name)
# var.align = ir_type.width // 8
builder.store(
ir.Constant(ir_type, rval.args[0].value), local_sym_tab[var_name][0]
)
print(
f"Assigned {call_type} constant "
f"{rval.args[0].value} to {var_name}"
)
# local_sym_tab[var_name] = var
elif HelperHandlerRegistry.has_handler(call_type):
# var = builder.alloca(ir.IntType(64), name=var_name)
# var.align = 8
val = handle_helper_call(
rval,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
)
builder.store(val[0], local_sym_tab[var_name][0])
# local_sym_tab[var_name] = var
print(f"Assigned constant {rval.func.id} to {var_name}")
elif call_type == "deref" and len(rval.args) == 1:
print(f"Handling deref assignment {ast.dump(rval)}")
val = eval_expr(
func,
module,
builder,
rval,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
)
if val is None:
print("Failed to evaluate deref argument")
return
print(f"Dereferenced value: {val}, storing in {var_name}")
builder.store(val[0], local_sym_tab[var_name][0])
# local_sym_tab[var_name] = var
print(f"Dereferenced and assigned to {var_name}")
elif call_type in structs_sym_tab and len(rval.args) == 0:
struct_info = structs_sym_tab[call_type]
ir_type = struct_info.ir_type
# var = builder.alloca(ir_type, name=var_name)
# Null init
builder.store(ir.Constant(ir_type, None), local_sym_tab[var_name][0])
local_var_metadata[var_name] = call_type
print(f"Assigned struct {call_type} to {var_name}")
# local_sym_tab[var_name] = var
else:
print(f"Unsupported assignment call type: {call_type}")
elif isinstance(rval.func, ast.Attribute):
print(f"Assignment call attribute: {ast.dump(rval.func)}")
if isinstance(rval.func.value, ast.Name):
# TODO: probably a struct access
print(f"TODO STRUCT ACCESS {ast.dump(rval)}")
elif isinstance(rval.func.value, ast.Call) and isinstance(
rval.func.value.func, ast.Name
):
map_name = rval.func.value.func.id
method_name = rval.func.attr
if map_name in map_sym_tab:
if HelperHandlerRegistry.has_handler(method_name):
val = handle_helper_call(
rval,
module,
builder,
func,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
)
# var = builder.alloca(ir.IntType(64), name=var_name)
# var.align = 8
builder.store(val[0], local_sym_tab[var_name][0])
# local_sym_tab[var_name] = var
else:
print("Unsupported assignment call structure")
else:
print("Unsupported assignment call function type")
elif isinstance(rval, ast.BinOp):
handle_binary_op(
rval, module, builder, var_name, local_sym_tab, map_sym_tab, func
)
else:
print("Unsupported assignment value type")
def handle_cond(func, module, builder, cond, local_sym_tab, map_sym_tab):
if isinstance(cond, ast.Constant):
if isinstance(cond.value, bool):
return ir.Constant(ir.IntType(1), int(cond.value))
elif isinstance(cond.value, int):
return ir.Constant(ir.IntType(1), int(bool(cond.value)))
else:
print("Unsupported constant type in condition")
return None
elif isinstance(cond, ast.Name):
if cond.id in local_sym_tab:
var = local_sym_tab[cond.id][0]
val = builder.load(var)
if val.type != ir.IntType(1):
# Convert nonzero values to true, zero to false
if isinstance(val.type, ir.PointerType):
# For pointer types, compare with null pointer
zero = ir.Constant(val.type, None)
else:
# For integer types, compare with zero
zero = ir.Constant(val.type, 0)
val = builder.icmp_signed("!=", val, zero)
return val
else:
print(f"Undefined variable {cond.id} in condition")
return None
elif isinstance(cond, ast.Compare):
lhs = eval_expr(func, module, builder, cond.left, local_sym_tab, map_sym_tab)[0]
if len(cond.ops) != 1 or len(cond.comparators) != 1:
print("Unsupported complex comparison")
return None
rhs = eval_expr(
func, module, builder, cond.comparators[0], local_sym_tab, map_sym_tab
)[0]
op = cond.ops[0]
if lhs.type != rhs.type:
if isinstance(lhs.type, ir.IntType) and isinstance(rhs.type, ir.IntType):
# Extend the smaller type to the larger type
if lhs.type.width < rhs.type.width:
lhs = builder.sext(lhs, rhs.type)
elif lhs.type.width > rhs.type.width:
rhs = builder.sext(rhs, lhs.type)
else:
print("Type mismatch in comparison")
return None
if isinstance(op, ast.Eq):
return builder.icmp_signed("==", lhs, rhs)
elif isinstance(op, ast.NotEq):
return builder.icmp_signed("!=", lhs, rhs)
elif isinstance(op, ast.Lt):
return builder.icmp_signed("<", lhs, rhs)
elif isinstance(op, ast.LtE):
return builder.icmp_signed("<=", lhs, rhs)
elif isinstance(op, ast.Gt):
return builder.icmp_signed(">", lhs, rhs)
elif isinstance(op, ast.GtE):
return builder.icmp_signed(">=", lhs, rhs)
else:
print("Unsupported comparison operator")
return None
else:
print("Unsupported condition expression")
return None
def handle_if(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab=None
):
"""Handle if statements in the function body."""
print("Handling if statement")
# start = builder.block.parent
then_block = func.append_basic_block(name="if.then")
merge_block = func.append_basic_block(name="if.end")
if stmt.orelse:
else_block = func.append_basic_block(name="if.else")
else:
else_block = None
cond = handle_cond(func, module, builder, stmt.test, local_sym_tab, map_sym_tab)
if else_block:
builder.cbranch(cond, then_block, else_block)
else:
builder.cbranch(cond, then_block, merge_block)
builder.position_at_end(then_block)
for s in stmt.body:
process_stmt(
func, module, builder, s, local_sym_tab, map_sym_tab, structs_sym_tab, False
)
if not builder.block.is_terminated:
builder.branch(merge_block)
if else_block:
builder.position_at_end(else_block)
for s in stmt.orelse:
process_stmt(
func,
module,
builder,
s,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
False,
)
if not builder.block.is_terminated:
builder.branch(merge_block)
builder.position_at_end(merge_block)
def process_stmt(
func,
module,
builder,
stmt,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
did_return,
ret_type=ir.IntType(64),
):
print(f"Processing statement: {ast.dump(stmt)}")
if isinstance(stmt, ast.Expr):
print(local_var_metadata)
handle_expr(
func,
module,
builder,
stmt,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
local_var_metadata,
)
elif isinstance(stmt, ast.Assign):
handle_assign(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab
)
elif isinstance(stmt, ast.AugAssign):
raise SyntaxError("Augmented assignment not supported")
elif isinstance(stmt, ast.If):
handle_if(
func, module, builder, stmt, map_sym_tab, local_sym_tab, structs_sym_tab
)
elif isinstance(stmt, ast.Return):
if stmt.value is None:
builder.ret(ir.Constant(ir.IntType(32), 0))
did_return = True
elif (
isinstance(stmt.value, ast.Call)
and isinstance(stmt.value.func, ast.Name)
and len(stmt.value.args) == 1
and isinstance(stmt.value.args[0], ast.Constant)
and isinstance(stmt.value.args[0].value, int)
):
call_type = stmt.value.func.id
if ctypes_to_ir(call_type) != ret_type:
raise ValueError(
"Return type mismatch: expected"
f"{ctypes_to_ir(call_type)}, got {call_type}"
)
else:
builder.ret(ir.Constant(ret_type, stmt.value.args[0].value))
did_return = True
elif isinstance(stmt.value, ast.Name):
if stmt.value.id == "XDP_PASS":
builder.ret(ir.Constant(ret_type, 2))
did_return = True
elif stmt.value.id == "XDP_DROP":
builder.ret(ir.Constant(ret_type, 1))
did_return = True
else:
raise ValueError("Failed to evaluate return expression")
else:
raise ValueError("Unsupported return value")
return did_return
def allocate_mem(
module, builder, body, func, ret_type, map_sym_tab, local_sym_tab, structs_sym_tab
):
for stmt in body:
if isinstance(stmt, ast.If):
if stmt.body:
local_sym_tab = allocate_mem(
module,
builder,
stmt.body,
func,
ret_type,
map_sym_tab,
local_sym_tab,
structs_sym_tab,
)
if stmt.orelse:
local_sym_tab = allocate_mem(
module,
builder,
stmt.orelse,
func,
ret_type,
map_sym_tab,
local_sym_tab,
structs_sym_tab,
)
elif isinstance(stmt, ast.Assign):
if len(stmt.targets) != 1:
print("Unsupported multiassignment")
continue
target = stmt.targets[0]
if not isinstance(target, ast.Name):
print("Unsupported assignment target")
continue
var_name = target.id
rval = stmt.value
if isinstance(rval, ast.Call):
if isinstance(rval.func, ast.Name):
call_type = rval.func.id
if call_type in ("c_int32", "c_int64", "c_uint32", "c_uint64"):
ir_type = ctypes_to_ir(call_type)
var = builder.alloca(ir_type, name=var_name)
var.align = ir_type.width // 8
print(f"Pre-allocated variable {var_name} of type {call_type}")
elif HelperHandlerRegistry.has_handler(call_type):
# Assume return type is int64 for now
ir_type = ir.IntType(64)
var = builder.alloca(ir_type, name=var_name)
var.align = ir_type.width // 8
print(f"Pre-allocated variable {var_name} for helper")
elif call_type == "deref" and len(rval.args) == 1:
# Assume return type is int64 for now
ir_type = ir.IntType(64)
var = builder.alloca(ir_type, name=var_name)
var.align = ir_type.width // 8
print(f"Pre-allocated variable {var_name} for deref")
elif call_type in structs_sym_tab:
struct_info = structs_sym_tab[call_type]
ir_type = struct_info.ir_type
var = builder.alloca(ir_type, name=var_name)
local_var_metadata[var_name] = call_type
print(
f"Pre-allocated variable {var_name} "
f"for struct {call_type}"
)
elif isinstance(rval.func, ast.Attribute):
ir_type = ir.PointerType(ir.IntType(64))
var = builder.alloca(ir_type, name=var_name)
# var.align = ir_type.width // 8
print(f"Pre-allocated variable {var_name} for map")
else:
print("Unsupported assignment call function type")
continue
elif isinstance(rval, ast.Constant):
if isinstance(rval.value, bool):
ir_type = ir.IntType(1)
var = builder.alloca(ir_type, name=var_name)
var.align = 1
print(f"Pre-allocated variable {var_name} of type c_bool")
elif isinstance(rval.value, int):
# Assume c_int64 for now
ir_type = ir.IntType(64)
var = builder.alloca(ir_type, name=var_name)
var.align = ir_type.width // 8
print(f"Pre-allocated variable {var_name} of type c_int64")
elif isinstance(rval.value, str):
ir_type = ir.PointerType(ir.IntType(8))
var = builder.alloca(ir_type, name=var_name)
var.align = 8
print(f"Pre-allocated variable {var_name} of type string")
else:
print("Unsupported constant type")
continue
elif isinstance(rval, ast.BinOp):
# Assume c_int64 for now
ir_type = ir.IntType(64)
var = builder.alloca(ir_type, name=var_name)
var.align = ir_type.width // 8
print(f"Pre-allocated variable {var_name} of type c_int64")
else:
print("Unsupported assignment value type")
continue
local_sym_tab[var_name] = (var, ir_type)
return local_sym_tab
def process_func_body(
module, builder, func_node, func, ret_type, map_sym_tab, structs_sym_tab
):
"""Process the body of a bpf function"""
# TODO: A lot. We just have print -> bpf_trace_printk for now
did_return = False
local_sym_tab = {}
# pre-allocate dynamic variables
local_sym_tab = allocate_mem(
module,
builder,
func_node.body,
func,
ret_type,
map_sym_tab,
local_sym_tab,
structs_sym_tab,
)
print(f"Local symbol table: {local_sym_tab.keys()}")
for stmt in func_node.body:
did_return = process_stmt(
func,
module,
builder,
stmt,
local_sym_tab,
map_sym_tab,
structs_sym_tab,
did_return,
ret_type,
)
if not did_return:
builder.ret(ir.Constant(ir.IntType(32), 0))
def process_bpf_chunk(func_node, module, return_type, map_sym_tab, structs_sym_tab):
"""Process a single BPF chunk (function) and emit corresponding LLVM IR."""
func_name = func_node.name
ret_type = return_type
# TODO: parse parameters
param_types = []
if func_node.args.args:
# Assume first arg to be ctx
param_types.append(ir.PointerType())
func_ty = ir.FunctionType(ret_type, param_types)
func = ir.Function(module, func_ty, func_name)
func.linkage = "dso_local"
func.attributes.add("nounwind")
func.attributes.add("noinline")
func.attributes.add("optnone")
if func_node.args.args:
# Only look at the first argument for now
param = func.args[0]
param.add_attribute("nocapture")
probe_string = get_probe_string(func_node)
if probe_string is not None:
func.section = probe_string
block = func.append_basic_block(name="entry")
builder = ir.IRBuilder(block)
process_func_body(
module, builder, func_node, func, ret_type, map_sym_tab, structs_sym_tab
)
return func
def func_proc(tree, module, chunks, map_sym_tab, structs_sym_tab):
for func_node in chunks:
is_global = False
for decorator in func_node.decorator_list:
if isinstance(decorator, ast.Name) and decorator.id in (
"map",
"bpfglobal",
"struct",
):
is_global = True
break
if is_global:
continue
func_type = get_probe_string(func_node)
print(f"Found probe_string of {func_node.name}: {func_type}")
process_bpf_chunk(
func_node,
module,
ctypes_to_ir(infer_return_type(func_node)),
map_sym_tab,
structs_sym_tab,
)
def infer_return_type(func_node: ast.FunctionDef):
if not isinstance(func_node, (ast.FunctionDef, ast.AsyncFunctionDef)):
raise TypeError("Expected ast.FunctionDef")
if func_node.returns is not None:
try:
return ast.unparse(func_node.returns)
except Exception:
node = func_node.returns
if isinstance(node, ast.Name):
return node.id
if isinstance(node, ast.Attribute):
return getattr(node, "attr", type(node).__name__)
try:
return str(node)
except Exception:
return type(node).__name__
found_type = None
def _expr_type(e):
if e is None:
return "None"
if isinstance(e, ast.Constant):
return type(e.value).__name__
if isinstance(e, ast.Name):
return e.id
if isinstance(e, ast.Call):
f = e.func
if isinstance(f, ast.Name):
return f.id
if isinstance(f, ast.Attribute):
try:
return ast.unparse(f)
except Exception:
return getattr(f, "attr", type(f).__name__)
try:
return ast.unparse(f)
except Exception:
return type(f).__name__
if isinstance(e, ast.Attribute):
try:
return ast.unparse(e)
except Exception:
return getattr(e, "attr", type(e).__name__)
try:
return ast.unparse(e)
except Exception:
return type(e).__name__
for walked_node in ast.walk(func_node):
if isinstance(walked_node, ast.Return):
t = _expr_type(walked_node.value)
if found_type is None:
found_type = t
elif found_type != t:
raise ValueError("Conflicting return types:" f"{found_type} vs {t}")
return found_type or "None"
# For string assignment to fixed-size arrays
def assign_string_to_array(builder, target_array_ptr, source_string_ptr, array_length):
"""
Copy a string (i8*) to a fixed-size array ([N x i8]*)
"""
# Create a loop to copy characters one by one
# entry_block = builder.block
copy_block = builder.append_basic_block("copy_char")
end_block = builder.append_basic_block("copy_end")
# Create loop counter
i = builder.alloca(ir.IntType(32))
builder.store(ir.Constant(ir.IntType(32), 0), i)
# Start the loop
builder.branch(copy_block)
# Copy loop
builder.position_at_end(copy_block)
idx = builder.load(i)
in_bounds = builder.icmp_unsigned(
"<", idx, ir.Constant(ir.IntType(32), array_length)
)
builder.cbranch(in_bounds, copy_block, end_block)
with builder.if_then(in_bounds):
# Load character from source
src_ptr = builder.gep(source_string_ptr, [idx])
char = builder.load(src_ptr)
# Store character in target
dst_ptr = builder.gep(target_array_ptr, [ir.Constant(ir.IntType(32), 0), idx])
builder.store(char, dst_ptr)
# Increment counter
next_idx = builder.add(idx, ir.Constant(ir.IntType(32), 1))
builder.store(next_idx, i)
builder.position_at_end(end_block)
# Ensure null termination
last_idx = ir.Constant(ir.IntType(32), array_length - 1)
null_ptr = builder.gep(target_array_ptr, [ir.Constant(ir.IntType(32), 0), last_idx])
builder.store(ir.Constant(ir.IntType(8), 0), null_ptr)

View File

@ -1,121 +1,8 @@
from llvmlite import ir
import ast
from logging import Logger
import logging
from .type_deducer import ctypes_to_ir
logger: Logger = logging.getLogger(__name__)
# TODO: this is going to be a huge fuck of a headache in the future.
global_sym_tab = []
def populate_global_symbol_table(tree, module: ir.Module):
for node in tree.body:
if isinstance(node, ast.FunctionDef):
for dec in node.decorator_list:
if (
isinstance(dec, ast.Call)
and isinstance(dec.func, ast.Name)
and dec.func.id == "section"
and len(dec.args) == 1
and isinstance(dec.args[0], ast.Constant)
and isinstance(dec.args[0].value, str)
):
global_sym_tab.append(node)
elif isinstance(dec, ast.Name) and dec.id == "bpfglobal":
global_sym_tab.append(node)
elif isinstance(dec, ast.Name) and dec.id == "map":
global_sym_tab.append(node)
return False
def emit_global(module: ir.Module, node, name):
logger.info(f"global identifier {name} processing")
# deduce LLVM type from the annotated return
if not isinstance(node.returns, ast.Name):
raise ValueError(f"Unsupported return annotation {ast.dump(node.returns)}")
ty = ctypes_to_ir(node.returns.id)
# extract the return expression
# TODO: turn this return extractor into a generic function I can use everywhere.
ret_stmt = node.body[0]
if not isinstance(ret_stmt, ast.Return) or ret_stmt.value is None:
raise ValueError(f"Global '{name}' has no valid return")
init_val = ret_stmt.value
# simple constant like "return 0"
if isinstance(init_val, ast.Constant):
llvm_init = ir.Constant(ty, init_val.value)
# variable reference like "return SOME_CONST"
elif isinstance(init_val, ast.Name):
# need symbol resolution here, stub as 0 for now
raise ValueError(f"Name reference {init_val.id} not yet supported")
# constructor call like "return c_int64(0)" or dataclass(...)
elif isinstance(init_val, ast.Call):
if len(init_val.args) >= 1 and isinstance(init_val.args[0], ast.Constant):
llvm_init = ir.Constant(ty, init_val.args[0].value)
else:
logger.info("Defaulting to zero as no constant argument found")
llvm_init = ir.Constant(ty, 0)
else:
raise ValueError(f"Unsupported return expr {ast.dump(init_val)}")
gvar = ir.GlobalVariable(module, ty, name=name)
gvar.initializer = llvm_init
gvar.align = 8
gvar.linkage = "dso_local"
gvar.global_constant = False
return gvar
def globals_processing(tree, module):
"""Process stuff decorated with @bpf and @bpfglobal except license and return the section name"""
globals_sym_tab = []
for node in tree.body:
# Skip non-assignment and non-function nodes
if not (isinstance(node, ast.FunctionDef)):
continue
# Get the name based on node type
if isinstance(node, ast.FunctionDef):
name = node.name
else:
continue
# Check for duplicate names
if name in globals_sym_tab:
raise SyntaxError(f"ERROR: Global name '{name}' previously defined")
else:
globals_sym_tab.append(name)
if isinstance(node, ast.FunctionDef) and node.name != "LICENSE":
decorators = [
dec.id for dec in node.decorator_list if isinstance(dec, ast.Name)
]
if "bpf" in decorators and "bpfglobal" in decorators:
if (
len(node.body) == 1
and isinstance(node.body[0], ast.Return)
and node.body[0].value is not None
and isinstance(
node.body[0].value, (ast.Constant, ast.Name, ast.Call)
)
):
emit_global(module, node, name)
else:
raise SyntaxError(f"ERROR: Invalid syntax for {name} global")
return None
def emit_llvm_compiler_used(module: ir.Module, names: list[str]):
def emit_globals(module: ir.Module, names: list[str]):
"""
Emit the @llvm.compiler.used global given a list of function/global names.
"""
@ -137,7 +24,7 @@ def emit_llvm_compiler_used(module: ir.Module, names: list[str]):
gv.section = "llvm.metadata"
def globals_list_creation(tree, module: ir.Module):
def globals_processing(tree, module: ir.Module):
collected = ["LICENSE"]
for node in tree.body:
@ -153,11 +40,10 @@ def globals_list_creation(tree, module: ir.Module):
):
collected.append(node.name)
# NOTE: all globals other than
# elif isinstance(dec, ast.Name) and dec.id == "bpfglobal":
# collected.append(node.name)
elif isinstance(dec, ast.Name) and dec.id == "bpfglobal":
collected.append(node.name)
elif isinstance(dec, ast.Name) and dec.id == "map":
collected.append(node.name)
emit_llvm_compiler_used(module, collected)
emit_globals(module, collected)

View File

@ -1,10 +1,9 @@
from .helper_utils import HelperHandlerRegistry, reset_scratch_pool
from .helper_utils import HelperHandlerRegistry
from .bpf_helper_handler import handle_helper_call
from .helpers import ktime, pid, deref, XDP_DROP, XDP_PASS
__all__ = [
"HelperHandlerRegistry",
"reset_scratch_pool",
"handle_helper_call",
"ktime",
"pid",

View File

@ -9,10 +9,6 @@ from .helper_utils import (
simple_string_print,
get_data_ptr_and_size,
)
from logging import Logger
import logging
logger: Logger = logging.getLogger(__name__)
class BPFHelperID(Enum):
@ -23,6 +19,8 @@ class BPFHelperID(Enum):
BPF_PRINTK = 6
BPF_GET_CURRENT_PID_TGID = 14
BPF_PERF_EVENT_OUTPUT = 25
BPF_RINGBUF_RESERVE = 131
BPF_RINGBUF_SUBMIT = 132
@HelperHandlerRegistry.register("ktime")
@ -34,7 +32,7 @@ def bpf_ktime_get_ns_emitter(
func,
local_sym_tab=None,
struct_sym_tab=None,
map_sym_tab=None,
local_var_metadata=None,
):
"""
Emit LLVM IR for bpf_ktime_get_ns helper function call.
@ -57,26 +55,20 @@ def bpf_map_lookup_elem_emitter(
func,
local_sym_tab=None,
struct_sym_tab=None,
map_sym_tab=None,
local_var_metadata=None,
):
"""
Emit LLVM IR for bpf_map_lookup_elem helper function call.
"""
if not call.args or len(call.args) != 1:
raise ValueError(
f"Map lookup expects exactly one argument (key), got {len(call.args)}"
"Map lookup expects exactly one argument (key), got " f"{len(call.args)}"
)
key_ptr = get_or_create_ptr_from_arg(
func, module, call.args[0], builder, local_sym_tab, map_sym_tab, struct_sym_tab
)
key_ptr = get_or_create_ptr_from_arg(call.args[0], builder, local_sym_tab)
map_void_ptr = builder.bitcast(map_ptr, ir.PointerType())
# TODO: I have changed the return type to i64*, as we are
# allocating space for that type in allocate_mem. This is
# temporary, and we will honour other widths later. But this
# allows us to have cool binary ops on the returned value.
fn_type = ir.FunctionType(
ir.PointerType(ir.IntType(64)), # Return type: void*
ir.PointerType(), # Return type: void*
[ir.PointerType(), ir.PointerType()], # Args: (void*, void*)
var_arg=False,
)
@ -99,7 +91,7 @@ def bpf_printk_emitter(
func,
local_sym_tab=None,
struct_sym_tab=None,
map_sym_tab=None,
local_var_metadata=None,
):
"""Emit LLVM IR for bpf_printk helper function call."""
if not hasattr(func, "_fmt_counter"):
@ -117,6 +109,7 @@ def bpf_printk_emitter(
func,
local_sym_tab,
struct_sym_tab,
local_var_metadata,
)
elif isinstance(call.args[0], ast.Constant) and isinstance(call.args[0].value, str):
# TODO: We are only supporting single arguments for now.
@ -147,7 +140,7 @@ def bpf_map_update_elem_emitter(
func,
local_sym_tab=None,
struct_sym_tab=None,
map_sym_tab=None,
local_var_metadata=None,
):
"""
Emit LLVM IR for bpf_map_update_elem helper function call.
@ -155,19 +148,16 @@ def bpf_map_update_elem_emitter(
"""
if not call.args or len(call.args) < 2 or len(call.args) > 3:
raise ValueError(
f"Map update expects 2 or 3 args (key, value, flags), got {len(call.args)}"
"Map update expects 2 or 3 args (key, value, flags), "
f"got {len(call.args)}"
)
key_arg = call.args[0]
value_arg = call.args[1]
flags_arg = call.args[2] if len(call.args) > 2 else None
key_ptr = get_or_create_ptr_from_arg(
func, module, key_arg, builder, local_sym_tab, map_sym_tab, struct_sym_tab
)
value_ptr = get_or_create_ptr_from_arg(
func, module, value_arg, builder, local_sym_tab, map_sym_tab, struct_sym_tab
)
key_ptr = get_or_create_ptr_from_arg(key_arg, builder, local_sym_tab)
value_ptr = get_or_create_ptr_from_arg(value_arg, builder, local_sym_tab)
flags_val = get_flags_val(flags_arg, builder, local_sym_tab)
map_void_ptr = builder.bitcast(map_ptr, ir.PointerType())
@ -192,6 +182,114 @@ def bpf_map_update_elem_emitter(
return result, None
@HelperHandlerRegistry.register("submit")
def bpf_ringbuf_submit_emitter(
call,
map_ptr,
module,
builder,
func,
local_sym_tab=None,
struct_sym_tab=None,
local_var_metadata=None,
):
"""
Emit LLVM IR for bpf_ringbuf_submit helper function call.
Expected call signature: ringbuf.submit(data, flags=0)
"""
if not call.args or len(call.args) < 1 or len(call.args) > 2:
raise ValueError(
"Ringbuf submit expects 1 or 2 args (data, flags), "
f"got {len(call.args)}"
)
data_arg = call.args[0]
data_ptr = get_or_create_ptr_from_arg(data_arg, builder, local_sym_tab)
# Get flags argument (default to 0)
flags_arg = call.args[1] if len(call.args) > 1 else None
flags_val = get_flags_val(flags_arg, builder, local_sym_tab)
# Returns: void
# Args: (void* data, u64 flags)
fn_type = ir.FunctionType(
ir.VoidType(),
[ir.PointerType(), ir.IntType(64)],
var_arg=False,
)
fn_ptr_type = ir.PointerType(fn_type)
fn_addr = ir.Constant(ir.IntType(64), BPFHelperID.BPF_RINGBUF_SUBMIT.value)
fn_ptr = builder.inttoptr(fn_addr, fn_ptr_type)
if isinstance(flags_val, int):
flags_const = ir.Constant(ir.IntType(64), flags_val)
else:
flags_const = flags_val
builder.call(fn_ptr, [data_ptr, flags_const], tail=True)
return None
@HelperHandlerRegistry.register("reserve")
def bpf_ringbuf_reserve_emitter(
call,
map_ptr,
module,
builder,
func,
local_sym_tab=None,
struct_sym_tab=None,
local_var_metadata=None,
):
"""
Emit LLVM IR for bpf_ringbuf_reserve helper function call.
Expected call signature: ringbuf.reserve(size, flags=0)
"""
if not call.args or len(call.args) < 1 or len(call.args) > 2:
raise ValueError(
"Ringbuf reserve expects 1 or 2 args (size, flags), "
f"got {len(call.args)}"
)
# TODO: here, getting length of stuff does not actually work. need to fix this.
size_arg = call.args[0]
if isinstance(size_arg, ast.Constant):
size_val = ir.Constant(ir.IntType(64), size_arg.value)
elif isinstance(size_arg, ast.Name):
if size_arg.id not in local_sym_tab:
raise ValueError(
f"Variable '{size_arg.id}' not found in local symbol table"
)
size_val = builder.load(local_sym_tab[size_arg.id])
else:
raise NotImplementedError(f"Unsupported size argument type: {type(size_arg)}")
flags_arg = call.args[1] if len(call.args) > 1 else None
flags_val = get_flags_val(flags_arg, builder, local_sym_tab)
map_void_ptr = builder.bitcast(map_ptr, ir.PointerType())
# Args: (void* ringbuf, u64 size, u64 flags)
fn_type = ir.FunctionType(
ir.PointerType(),
[ir.PointerType(), ir.IntType(64), ir.IntType(64)],
var_arg=False,
)
fn_ptr_type = ir.PointerType(fn_type)
fn_addr = ir.Constant(ir.IntType(64), BPFHelperID.BPF_RINGBUF_RESERVE.value)
fn_ptr = builder.inttoptr(fn_addr, fn_ptr_type)
if isinstance(flags_val, int):
flags_const = ir.Constant(ir.IntType(64), flags_val)
else:
flags_const = flags_val
result = builder.call(fn_ptr, [map_void_ptr, size_val, flags_const], tail=True)
return result, ir.PointerType()
@HelperHandlerRegistry.register("delete")
def bpf_map_delete_elem_emitter(
@ -202,7 +300,7 @@ def bpf_map_delete_elem_emitter(
func,
local_sym_tab=None,
struct_sym_tab=None,
map_sym_tab=None,
local_var_metadata=None,
):
"""
Emit LLVM IR for bpf_map_delete_elem helper function call.
@ -210,11 +308,9 @@ def bpf_map_delete_elem_emitter(
"""
if not call.args or len(call.args) != 1:
raise ValueError(
f"Map delete expects exactly one argument (key), got {len(call.args)}"
"Map delete expects exactly one argument (key), got " f"{len(call.args)}"
)
key_ptr = get_or_create_ptr_from_arg(
func, module, call.args[0], builder, local_sym_tab, map_sym_tab, struct_sym_tab
)
key_ptr = get_or_create_ptr_from_arg(call.args[0], builder, local_sym_tab)
map_void_ptr = builder.bitcast(map_ptr, ir.PointerType())
# Define function type for bpf_map_delete_elem
@ -242,7 +338,7 @@ def bpf_get_current_pid_tgid_emitter(
func,
local_sym_tab=None,
struct_sym_tab=None,
map_sym_tab=None,
local_var_metadata=None,
):
"""
Emit LLVM IR for bpf_get_current_pid_tgid helper function call.
@ -269,16 +365,18 @@ def bpf_perf_event_output_handler(
func,
local_sym_tab=None,
struct_sym_tab=None,
map_sym_tab=None,
local_var_metadata=None,
):
if len(call.args) != 1:
raise ValueError(
f"Perf event output expects exactly one argument, got {len(call.args)}"
"Perf event output expects exactly one argument, " f"got {len(call.args)}"
)
data_arg = call.args[0]
ctx_ptr = func.args[0] # First argument to the function is ctx
data_ptr, size_val = get_data_ptr_and_size(data_arg, local_sym_tab, struct_sym_tab)
data_ptr, size_val = get_data_ptr_and_size(
data_arg, local_sym_tab, struct_sym_tab, local_var_metadata
)
# BPF_F_CURRENT_CPU is -1 in 32 bit
flags_val = ir.Constant(ir.IntType(64), 0xFFFFFFFF)
@ -316,6 +414,7 @@ def handle_helper_call(
local_sym_tab=None,
map_sym_tab=None,
struct_sym_tab=None,
local_var_metadata=None,
):
"""Process a BPF helper function call and emit the appropriate LLVM IR."""
@ -334,7 +433,7 @@ def handle_helper_call(
func,
local_sym_tab,
struct_sym_tab,
map_sym_tab,
local_var_metadata,
)
# Handle direct function calls (e.g., print(), ktime())
@ -345,7 +444,7 @@ def handle_helper_call(
elif isinstance(call.func, ast.Attribute):
method_name = call.func.attr
value = call.func.value
logger.info(f"Handling method call: {ast.dump(call.func)}")
print(f"Handling method call: {ast.dump(call.func)}")
# Get map pointer from different styles of map access
if isinstance(value, ast.Call) and isinstance(value.func, ast.Name):
# Func style: my_map().lookup(key)

View File

@ -3,8 +3,7 @@ import logging
from collections.abc import Callable
from llvmlite import ir
from pythonbpf.expr import eval_expr, get_base_type_and_depth, deref_to_depth
from pythonbpf.binary_ops import get_operand_value
from pythonbpf.expr_pass import eval_expr
logger = logging.getLogger(__name__)
@ -35,83 +34,34 @@ class HelperHandlerRegistry:
return helper_name in cls._handlers
class ScratchPoolManager:
"""Manage the temporary helper variables in local_sym_tab"""
def __init__(self):
self._counter = 0
@property
def counter(self):
return self._counter
def reset(self):
self._counter = 0
logger.debug("Scratch pool counter reset to 0")
def get_next_temp(self, local_sym_tab):
temp_name = f"__helper_temp_{self._counter}"
self._counter += 1
if temp_name not in local_sym_tab:
raise ValueError(
f"Scratch pool exhausted or inadequate: {temp_name}. "
f"Current counter: {self._counter}"
)
return local_sym_tab[temp_name].var, temp_name
_temp_pool_manager = ScratchPoolManager() # Singleton instance
def reset_scratch_pool():
"""Reset the scratch pool counter"""
_temp_pool_manager.reset()
def get_var_ptr_from_name(var_name, local_sym_tab):
"""Get a pointer to a variable from the symbol table."""
if local_sym_tab and var_name in local_sym_tab:
return local_sym_tab[var_name].var
return local_sym_tab[var_name][0]
raise ValueError(f"Variable '{var_name}' not found in local symbol table")
def create_int_constant_ptr(value, builder, local_sym_tab, int_width=64):
def create_int_constant_ptr(value, builder, int_width=64):
"""Create a pointer to an integer constant."""
# Default to 64-bit integer
ptr, temp_name = _temp_pool_manager.get_next_temp(local_sym_tab)
logger.info(f"Using temp variable '{temp_name}' for int constant {value}")
const_val = ir.Constant(ir.IntType(int_width), value)
builder.store(const_val, ptr)
int_type = ir.IntType(int_width)
ptr = builder.alloca(int_type)
ptr.align = int_type.width // 8
builder.store(ir.Constant(int_type, value), ptr)
return ptr
def get_or_create_ptr_from_arg(
func, module, arg, builder, local_sym_tab, map_sym_tab, struct_sym_tab=None
):
def get_or_create_ptr_from_arg(arg, builder, local_sym_tab):
"""Extract or create pointer from the call arguments."""
if isinstance(arg, ast.Name):
ptr = get_var_ptr_from_name(arg.id, local_sym_tab)
elif isinstance(arg, ast.Constant) and isinstance(arg.value, int):
ptr = create_int_constant_ptr(arg.value, builder, local_sym_tab)
ptr = create_int_constant_ptr(arg.value, builder)
else:
# Evaluate the expression and store the result in a temp variable
val = get_operand_value(
func, module, arg, builder, local_sym_tab, map_sym_tab, struct_sym_tab
raise NotImplementedError(
"Only simple variable names are supported as args in map helpers."
)
if val is None:
raise ValueError("Failed to evaluate expression for helper arg.")
# NOTE: We assume the result is an int64 for now
# if isinstance(arg, ast.Attribute):
# return val
ptr, temp_name = _temp_pool_manager.get_next_temp(local_sym_tab)
logger.info(f"Using temp variable '{temp_name}' for expression result")
builder.store(val, ptr)
return ptr
@ -122,7 +72,7 @@ def get_flags_val(arg, builder, local_sym_tab):
if isinstance(arg, ast.Name):
if local_sym_tab and arg.id in local_sym_tab:
flags_ptr = local_sym_tab[arg.id].var
flags_ptr = local_sym_tab[arg.id][0]
return builder.load(flags_ptr)
else:
raise ValueError(f"Variable '{arg.id}' not found in local symbol table")
@ -150,6 +100,7 @@ def handle_fstring_print(
func,
local_sym_tab=None,
struct_sym_tab=None,
local_var_metadata=None,
):
"""Handle f-string formatting for bpf_printk emitter."""
fmt_parts = []
@ -167,6 +118,7 @@ def handle_fstring_print(
exprs,
local_sym_tab,
struct_sym_tab,
local_var_metadata,
)
else:
raise NotImplementedError(f"Unsupported f-string value type: {type(value)}")
@ -186,6 +138,7 @@ def handle_fstring_print(
builder,
local_sym_tab,
struct_sym_tab,
local_var_metadata,
)
args.append(arg_value)
@ -205,7 +158,9 @@ def _process_constant_in_fstring(cst, fmt_parts, exprs):
)
def _process_fval(fval, fmt_parts, exprs, local_sym_tab, struct_sym_tab):
def _process_fval(
fval, fmt_parts, exprs, local_sym_tab, struct_sym_tab, local_var_metadata
):
"""Process formatted values in f-string."""
logger.debug(f"Processing formatted value: {ast.dump(fval)}")
@ -218,6 +173,7 @@ def _process_fval(fval, fmt_parts, exprs, local_sym_tab, struct_sym_tab):
exprs,
local_sym_tab,
struct_sym_tab,
local_var_metadata,
)
else:
raise NotImplementedError(
@ -228,11 +184,13 @@ def _process_fval(fval, fmt_parts, exprs, local_sym_tab, struct_sym_tab):
def _process_name_in_fval(name_node, fmt_parts, exprs, local_sym_tab):
"""Process name nodes in formatted values."""
if local_sym_tab and name_node.id in local_sym_tab:
_, var_type, tmp = local_sym_tab[name_node.id]
_, var_type = local_sym_tab[name_node.id]
_populate_fval(var_type, name_node, fmt_parts, exprs)
def _process_attr_in_fval(attr_node, fmt_parts, exprs, local_sym_tab, struct_sym_tab):
def _process_attr_in_fval(
attr_node, fmt_parts, exprs, local_sym_tab, struct_sym_tab, local_var_metadata
):
"""Process attribute nodes in formatted values."""
if (
isinstance(attr_node.value, ast.Name)
@ -242,7 +200,12 @@ def _process_attr_in_fval(attr_node, fmt_parts, exprs, local_sym_tab, struct_sym
var_name = attr_node.value.id
field_name = attr_node.attr
var_type = local_sym_tab[var_name].metadata
if not local_var_metadata or var_name not in local_var_metadata:
raise ValueError(
f"Metadata for '{var_name}' not found in local var metadata"
)
var_type = local_var_metadata[var_name]
if var_type not in struct_sym_tab:
raise ValueError(
f"Struct '{var_type}' for '{var_name}' not in symbol table"
@ -274,27 +237,10 @@ def _populate_fval(ftype, node, fmt_parts, exprs):
raise NotImplementedError(
f"Unsupported integer width in f-string: {ftype.width}"
)
elif isinstance(ftype, ir.PointerType):
target, depth = get_base_type_and_depth(ftype)
if isinstance(target, ir.IntType):
if target.width == 64:
fmt_parts.append("%lld")
exprs.append(node)
elif target.width == 32:
fmt_parts.append("%d")
exprs.append(node)
elif target.width == 8 and depth == 1:
# NOTE: Assume i8* is a string
fmt_parts.append("%s")
exprs.append(node)
else:
raise NotImplementedError(
f"Unsupported pointer target type in f-string: {target}"
)
else:
raise NotImplementedError(
f"Unsupported pointer target type in f-string: {target}"
)
elif ftype == ir.PointerType(ir.IntType(8)):
# NOTE: We assume i8* is a string
fmt_parts.append("%s")
exprs.append(node)
else:
raise NotImplementedError(f"Unsupported field type in f-string: {ftype}")
@ -317,7 +263,9 @@ def _create_format_string_global(fmt_str, func, module, builder):
return builder.bitcast(fmt_gvar, ir.PointerType())
def _prepare_expr_args(expr, func, module, builder, local_sym_tab, struct_sym_tab):
def _prepare_expr_args(
expr, func, module, builder, local_sym_tab, struct_sym_tab, local_var_metadata
):
"""Evaluate and prepare an expression to use as an arg for bpf_printk."""
val, _ = eval_expr(
func,
@ -327,30 +275,18 @@ def _prepare_expr_args(expr, func, module, builder, local_sym_tab, struct_sym_ta
local_sym_tab,
None,
struct_sym_tab,
local_var_metadata,
)
if val:
if isinstance(val.type, ir.PointerType):
target, depth = get_base_type_and_depth(val.type)
if isinstance(target, ir.IntType):
if target.width >= 32:
val = deref_to_depth(func, builder, val, depth)
val = builder.sext(val, ir.IntType(64))
elif target.width == 8 and depth == 1:
# NOTE: i8* is string, no need to deref
pass
else:
logger.warning(
"Only int and ptr supported in bpf_printk args. Others default to 0."
)
val = ir.Constant(ir.IntType(64), 0)
val = builder.ptrtoint(val, ir.IntType(64))
elif isinstance(val.type, ir.IntType):
if val.type.width < 64:
val = builder.sext(val, ir.IntType(64))
else:
logger.warning(
"Only int and ptr supported in bpf_printk args. Others default to 0."
"Only int and ptr supported in bpf_printk args. " "Others default to 0."
)
val = ir.Constant(ir.IntType(64), 0)
return val
@ -362,26 +298,34 @@ def _prepare_expr_args(expr, func, module, builder, local_sym_tab, struct_sym_ta
return ir.Constant(ir.IntType(64), 0)
def get_data_ptr_and_size(data_arg, local_sym_tab, struct_sym_tab):
def get_data_ptr_and_size(data_arg, local_sym_tab, struct_sym_tab, local_var_metadata):
"""Extract data pointer and size information for perf event output."""
if isinstance(data_arg, ast.Name):
data_name = data_arg.id
if local_sym_tab and data_name in local_sym_tab:
data_ptr = local_sym_tab[data_name].var
data_ptr = local_sym_tab[data_name][0]
else:
raise ValueError(
f"Data variable {data_name} not found in local symbol table."
)
# Check if data_name is a struct
data_type = local_sym_tab[data_name].metadata
if data_type in struct_sym_tab:
struct_info = struct_sym_tab[data_type]
size_val = ir.Constant(ir.IntType(64), struct_info.size)
return data_ptr, size_val
if local_var_metadata and data_name in local_var_metadata:
data_type = local_var_metadata[data_name]
if data_type in struct_sym_tab:
struct_info = struct_sym_tab[data_type]
size_val = ir.Constant(ir.IntType(64), struct_info.size)
return data_ptr, size_val
else:
raise ValueError(
f"Struct {data_type} for {data_name} not in symbol table."
)
else:
raise ValueError(f"Struct {data_type} for {data_name} not in symbol table.")
raise ValueError(
f"Metadata for variable {data_name} "
"not found in local variable metadata."
)
else:
raise NotImplementedError(
"Only simple object names are supported as data in perf event output."
"Only simple object names are supported " "as data in perf event output."
)

View File

@ -1,9 +1,5 @@
from llvmlite import ir
import ast
from logging import Logger
import logging
logger: Logger = logging.getLogger(__name__)
def emit_license(module: ir.Module, license_str: str):
@ -45,9 +41,9 @@ def license_processing(tree, module):
emit_license(module, node.body[0].value.value)
return "LICENSE"
else:
logger.info("ERROR: LICENSE() must return a string literal")
print("ERROR: LICENSE() must return a string literal")
return None
else:
logger.info("ERROR: LICENSE already defined")
print("ERROR: LICENSE already defined")
return None
return None

View File

@ -3,7 +3,7 @@ from logging import Logger
from llvmlite import ir
from enum import Enum
from .maps_utils import MapProcessorRegistry
from pythonbpf.debuginfo import DebugInfoGenerator
from ..debuginfo import DebugInfoGenerator
import logging
logger: Logger = logging.getLogger(__name__)
@ -85,7 +85,7 @@ def create_bpf_map(module, map_name, map_params):
def create_map_debug_info(module, map_global, map_name, map_params):
"""Generate debug info metadata for BPF maps HASH and PERF_EVENT_ARRAY"""
"""Generate debug information metadata for BPF maps HASH and PERF_EVENT_ARRAY"""
generator = DebugInfoGenerator(module)
uint_type = generator.get_uint32_type()
@ -278,7 +278,9 @@ def process_bpf_map(func_node, module):
if handler:
return handler(map_name, rval, module)
else:
logger.warning(f"Unknown map type {rval.func.id}, defaulting to HashMap")
logger.warning(
f"Unknown map type " f"{rval.func.id}, defaulting to HashMap"
)
return process_hash_map(map_name, rval, module)
else:
raise ValueError("Function under @map must return a map")

View File

@ -19,7 +19,7 @@ def structs_proc(tree, module, chunks):
structs_sym_tab = {}
for cls_node in chunks:
if is_bpf_struct(cls_node):
logger.info(f"Found BPF struct: {cls_node.name}")
print(f"Found BPF struct: {cls_node.name}")
struct_info = process_bpf_struct(cls_node, module)
structs_sym_tab[cls_node.name] = struct_info
return structs_sym_tab

View File

@ -1,28 +1,24 @@
from llvmlite import ir
# TODO: THIS IS NOT SUPPOSED TO MATCH STRINGS :skull:
mapping = {
"c_int8": ir.IntType(8),
"c_uint8": ir.IntType(8),
"c_int16": ir.IntType(16),
"c_uint16": ir.IntType(16),
"c_int32": ir.IntType(32),
"c_uint32": ir.IntType(32),
"c_int64": ir.IntType(64),
"c_uint64": ir.IntType(64),
"c_float": ir.FloatType(),
"c_double": ir.DoubleType(),
"c_void_p": ir.IntType(64),
# Not so sure about this one
"str": ir.PointerType(ir.IntType(8)),
}
def ctypes_to_ir(ctype: str):
mapping = {
"c_int8": ir.IntType(8),
"c_uint8": ir.IntType(8),
"c_int16": ir.IntType(16),
"c_uint16": ir.IntType(16),
"c_int32": ir.IntType(32),
"c_uint32": ir.IntType(32),
"c_int64": ir.IntType(64),
"c_uint64": ir.IntType(64),
"c_float": ir.FloatType(),
"c_double": ir.DoubleType(),
"c_void_p": ir.IntType(64),
# Not so sure about this one
"str": ir.PointerType(ir.IntType(8)),
}
if ctype in mapping:
return mapping[ctype]
raise NotImplementedError(f"No mapping for {ctype}")
def is_ctypes(ctype: str) -> bool:
return ctype in mapping

View File

@ -1,27 +0,0 @@
// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include <linux/types.h>
struct test_struct {
__u64 a;
__u64 b;
};
struct test_struct w = {};
volatile __u64 prev_time = 0;
SEC("tracepoint/syscalls/sys_enter_execve")
int trace_execve(void *ctx)
{
bpf_printk("previous %ul now %ul", w.b, w.a);
__u64 ts = bpf_ktime_get_ns();
bpf_printk("prev %ul now %ul", prev_time, ts);
w.a = ts;
w.b = prev_time;
prev_time = ts;
return 0;
}
char LICENSE[] SEC("license") = "GPL";

View File

@ -1,19 +0,0 @@
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
char LICENSE[] SEC("license") = "Dual BSD/GPL";
SEC("kprobe/do_unlinkat")
int kprobe_execve(struct pt_regs *ctx)
{
bpf_printk("unlinkat created");
return 0;
}
SEC("kretprobe/do_unlinkat")
int kretprobe_execve(struct pt_regs *ctx)
{
bpf_printk("unlinkat returned\n");
return 0;
}

View File

@ -22,27 +22,29 @@ struct {
SEC("tracepoint/syscalls/sys_enter_execve")
int trace_execve(void *ctx)
{
struct event *e;
__u64 pid_tgid;
__u64 uid_gid;
// struct event *e;
// __u64 pid_tgid;
// __u64 uid_gid;
__u32 *e;
// Reserve space in the ringbuffer
e = bpf_ringbuf_reserve(&events, sizeof(*e), 0);
if (!e)
return 0;
//
// // Fill the struct with data
// pid_tgid = bpf_get_current_pid_tgid();
// e->pid = pid_tgid >> 32;
//
// uid_gid = bpf_get_current_uid_gid();
// e->uid = uid_gid & 0xFFFFFFFF;
//
// e->timestamp = bpf_ktime_get_ns();
// Fill the struct with data
pid_tgid = bpf_get_current_pid_tgid();
e->pid = pid_tgid >> 32;
uid_gid = bpf_get_current_uid_gid();
e->uid = uid_gid & 0xFFFFFFFF;
e->timestamp = bpf_ktime_get_ns();
bpf_get_current_comm(&e->comm, sizeof(e->comm));
// Submit the event to ringbuffer
// bpf_get_current_comm(&e->comm, sizeof(e->comm));
//
// // Submit the event to ringbuffer
__u32 temp = 32;
e = &temp;
bpf_ringbuf_submit(e, 0);
return 0;

View File

@ -1,39 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
# NOTE: This example tries to reinterpret the variable `x` to a different type.
# We do not allow this for now, as stack allocations are typed and have to be
# done in the first basic block. Allowing re-interpretation would require
# re-allocation of stack space (possibly in a new basic block), which is not
# supported in eBPF yet.
# We can allow bitcasts in cases where the width of the types is the same in
# the future. But for now, we do not allow any re-interpretation of variables.
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
last.update(0, 1)
x = last.lookup(0)
x = 20
if x == 2:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

View File

@ -3,9 +3,9 @@ from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_sync")
@section("sometag1")
def sometag(ctx: c_void_p) -> c_int64:
a = 1 + 2 + 1 + 12 + 13
a = 1 + 2 + 1
print(f"{a}")
return c_int64(0)

View File

@ -1,5 +1,3 @@
import logging
from pythonbpf import compile, bpf, section, bpfglobal
from ctypes import c_void_p, c_int64
@ -7,7 +5,8 @@ from ctypes import c_void_p, c_int64
@bpf
@section("sometag1")
def sometag(ctx: c_void_p) -> c_int64:
a = 1 - 1
b = 1 + 2
a = 1 + b
return c_int64(a)
@ -17,4 +16,4 @@ def LICENSE() -> str:
return "GPL"
compile(loglevel=logging.INFO)
compile()

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@ -0,0 +1,33 @@
from pythonbpf import bpf, map, bpfglobal, section, compile, compile_to_ir, BPF
from pythonbpf.maps import RingBuf
from ctypes import c_int32, c_void_p
# Define a map
@bpf
@map
def mymap() -> RingBuf:
return RingBuf(max_entries=(1024))
@bpf
@section("tracepoint/syscalls/sys_enter_clone")
def random_section(ctx: c_void_p) -> c_int32:
e: c_int32 = mymap().reserve(64)
if e == 0: # here is the issue i think
return c_int32(0)
mymap().submit(e)
return c_int32(0)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile_to_ir("ringbuf.py", "ringbuf.ll")
compile()
b = BPF()
b.load_and_attach()
while True:
print("running")

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@ -1,34 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
# NOTE: Decided against fixing this
# as a workaround is assigning the result of lookup to a variable
# and then using that variable in the if statement.
# Might fix in future.
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
last.update(0, 1)
if last.lookup(0) > 0:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,18 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!") if True else print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,34 +0,0 @@
from pythonbpf import bpf, struct, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
# NOTE: Decided against fixing this
# as one workaround is to just check any field of the struct
# in the if statement. Ugly but works.
# Might fix in future.
@bpf
@struct
class data_t:
pid: c_uint64
ts: c_uint64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
dat = data_t()
if dat:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -4,18 +4,6 @@ from pythonbpf.maps import HashMap
from ctypes import c_void_p, c_int64
# NOTE: I have decided to not fix this example for now.
# The issue is in line 31, where we are passing an expression.
# The update helper expects a pointer type. But the problem is
# that we must allocate the space for said pointer in the first
# basic block. As that usage is in a different basic block, we
# are unable to cast the expression to a pointer type. (as we never
# allocated space for it).
# Shall we change our space allocation logic? That allows users to
# spam the same helper with the same args, and still run out of
# stack space. So we consider this usage invalid for now.
# Might fix it later.
@bpf
@map
@ -26,12 +14,12 @@ def count() -> HashMap:
@bpf
@section("xdp")
def hello_world(ctx: c_void_p) -> c_int64:
prev = count.lookup(0)
prev = count().lookup(0)
if prev:
count.update(0, prev + 1)
count().update(0, prev + 1)
return XDP_PASS
else:
count.update(0, 1)
count().update(0, 1)
return XDP_PASS

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@ -1,101 +0,0 @@
import logging
from pythonbpf import compile, bpf, section, bpfglobal, compile_to_ir
from ctypes import c_void_p, c_int64, c_int32
@bpf
@bpfglobal
def somevalue() -> c_int32:
return c_int32(42)
@bpf
@bpfglobal
def somevalue2() -> c_int64:
return c_int64(69)
@bpf
@bpfglobal
def somevalue1() -> c_int32:
return c_int32(42)
# --- Passing examples ---
# Simple constant return
@bpf
@bpfglobal
def g1() -> c_int64:
return c_int64(42)
# Constructor with one constant argument
@bpf
@bpfglobal
def g2() -> c_int64:
return c_int64(69)
# --- Failing examples ---
# No return annotation
# @bpf
# @bpfglobal
# def g3():
# return 42
# Return annotation is complex
# @bpf
# @bpfglobal
# def g4() -> List[int]:
# return []
# # Return is missing
# @bpf
# @bpfglobal
# def g5() -> c_int64:
# pass
# # Return is a variable reference
# #TODO: maybe fix this sometime later. It defaults to 0
# CONST = 5
# @bpf
# @bpfglobal
# def g6() -> c_int64:
# return c_int64(CONST)
# Constructor with multiple args
#TODO: this is not working. should it work ?
@bpf
@bpfglobal
def g7() -> c_int64:
return c_int64(1)
# Dataclass call
#TODO: fails with dataclass
# @dataclass
# class Point:
# x: c_int64
# y: c_int64
# @bpf
# @bpfglobal
# def g8() -> Point:
# return Point(1, 2)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def sometag(ctx: c_void_p) -> c_int64:
print("test")
global somevalue
somevalue = 2
print(f"{somevalue}")
return c_int64(1)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile_to_ir("globals.py", "globals.ll", loglevel=logging.INFO)
compile()

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@ -1,40 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from pythonbpf.helper import XDP_PASS
from pythonbpf.maps import HashMap
from ctypes import c_void_p, c_int64
# NOTE: This example exposes the problems with our typing system.
# We can't do steps on line 25 and 27.
# prev is of type i64**. For prev + 1, we deref it down to i64
# To assign it back to prev, we need to go back to i64**.
# We cannot allocate space for the intermediate type now.
# We probably need to track the ref/deref chain for each variable.
@bpf
@map
def count() -> HashMap:
return HashMap(key=c_int64, value=c_int64, max_entries=1)
@bpf
@section("xdp")
def hello_world(ctx: c_void_p) -> c_int64:
prev = count.lookup(0)
if prev:
prev = prev + 1
count.update(0, prev)
return XDP_PASS
else:
count.update(0, 1)
return XDP_PASS
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,21 +0,0 @@
import logging
from pythonbpf import compile, bpf, section, bpfglobal, compile_to_ir
from ctypes import c_void_p, c_int64
# This should not pass as somevalue is not declared at all.
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def sometag(ctx: c_void_p) -> c_int64:
print("test")
print(f"{somevalue}") # noqa: F821
return c_int64(1)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile_to_ir("globals.py", "globals.ll", loglevel=logging.INFO)
compile()

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@ -1,69 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile, struct
from ctypes import c_void_p, c_int64, c_int32, c_uint64
from pythonbpf.maps import HashMap
from pythonbpf.helper import ktime
# NOTE: This is a comprehensive test combining struct, helper, and map features
# Please note that at line 50, though we have used an absurd expression to test
# the compiler, it is recommended to use named variables to reduce the amount of
# scratch space that needs to be allocated.
@bpf
@struct
class data_t:
pid: c_uint64
ts: c_uint64
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
dat = data_t()
dat.pid = 123
dat.pid = dat.pid + 1
print(f"pid is {dat.pid}")
tu = 9
last.update(0, tu)
last.update(1, -last.lookup(0))
x = last.lookup(0)
print(f"Map value at index 0: {x}")
x = x + c_int32(1)
print(f"x after adding 32-bit 1 is {x}")
x = ktime() - 121
print(f"ktime - 121 is {x}")
x = last.lookup(0)
x = x + 1
print(f"x is {x}")
if x == 10:
jat = data_t()
jat.ts = 456
print(f"Hello, World!, ts is {jat.ts}")
a = last.lookup(0)
print(f"a is {a}")
last.update(9, 9)
last.update(0, last.lookup(last.lookup(0)) +
last.lookup(last.lookup(0)) + last.lookup(last.lookup(0)))
z = last.lookup(0)
print(f"new map val at index 0 is {z}")
else:
a = last.lookup(0)
print("Goodbye, World!")
c = last.lookup(1 - 1)
print(f"c is {c}")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,27 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
x = 1
print(f"Initial x: {x}")
a = 20
x = a
print(f"Updated x with a: {x}")
x = (x + x) * 3
if x == 2:
print("Hello, World!")
else:
print(f"Goodbye, World! {x}")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,34 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
# NOTE: An example of i64** assignment with binops on the RHS
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
last.update(0, 1)
x = last.lookup(0)
print(f"{x}")
x = x + 1
if x == 2:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,40 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile, struct
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.helper import ktime
@bpf
@struct
class data_t:
pid: c_uint64
ts: c_uint64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
dat = data_t()
dat.pid = 123
dat.pid = dat.pid + 1
print(f"pid is {dat.pid}")
x = ktime() - 121
print(f"ktime is {x}")
x = 1
x = x + 1
print(f"x is {x}")
if x == 2:
jat = data_t()
jat.ts = 456
print(f"Hello, World!, ts is {jat.ts}")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,20 +0,0 @@
from pythonbpf import compile, bpf, section, bpfglobal
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_sync")
def sometag(ctx: c_void_p) -> c_int64:
b = 1 + 2
a = 1 + b
print(f"{a}")
return c_int64(0)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,32 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
last.update(0, 1)
last.update(1, 2)
x = last.lookup(0)
y = last.lookup(1)
if x and y:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,21 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
if True:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,21 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
if (0 + 1) * 0:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,21 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
if 0:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,30 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
# last.update(0, 1)
tsp = last.lookup(0)
if tsp:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,30 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
last.update(0, 1)
tsp = last.lookup(0)
if tsp > 0:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,30 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
# last.update(0, 1)
tsp = last.lookup(0)
if not tsp:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,32 +0,0 @@
from pythonbpf import bpf, map, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
from pythonbpf.maps import HashMap
@bpf
@map
def last() -> HashMap:
return HashMap(key=c_uint64, value=c_uint64, max_entries=3)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
last.update(0, 1)
# last.update(1, 2)
x = last.lookup(0)
y = last.lookup(1)
if x or y:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,29 +0,0 @@
from pythonbpf import bpf, struct, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_uint64
@bpf
@struct
class data_t:
pid: c_uint64
ts: c_uint64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
dat = data_t()
if dat.ts:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,23 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64, c_int32
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
x = 0
y = c_int32(0)
if x == y:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,22 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
x = 0
if x:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,22 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
x = 0
if x * 1:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,22 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
x = 2
if x > 3:
print("Hello, World!")
else:
print("Goodbye, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,7 +1,7 @@
from pythonbpf import bpf, map, struct, section, bpfglobal, compile, compile_to_ir, BPF
from pythonbpf.helper import ktime, pid
from pythonbpf.maps import PerfEventArray
import logging
from ctypes import c_void_p, c_int32, c_uint64
@ -42,8 +42,8 @@ def LICENSE() -> str:
return "GPL"
compile()
compile_to_ir("perf_buffer_map.py", "perf_buffer_map.ll")
compile(loglevel=logging.INFO)
b = BPF()
b.load_and_attach()

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@ -1,18 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
return 1 + 1 - 2
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,19 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
a = 2
return a - 2
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,18 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
return True
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,18 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
return 1
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,18 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
return
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,20 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int32
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int32:
print("Hello, World!")
a = 1 # int64
x = 1 # int64
return c_int32(a - x) # typecast to int32
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,18 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int32
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int32:
print("Hello, World!")
return c_int32(1)
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,19 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int32
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int32:
print("Hello, World!")
a = 1 # int64
return c_int32(a) # typecast to int32
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,19 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
a = 1
return a
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,19 +0,0 @@
from pythonbpf import bpf, section, bpfglobal, compile
from ctypes import c_void_p, c_int64
from pythonbpf.helper import XDP_PASS
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello_world(ctx: c_void_p) -> c_int64:
print("Hello, World!")
return XDP_PASS
@bpf
@bpfglobal
def LICENSE() -> str:
return "GPL"
compile()

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@ -1,5 +1,5 @@
from pythonbpf import bpf, BPF, map, bpfglobal, section, compile, compile_to_ir
from pythonbpf.maps import RingBuf, HashMap
from pythonbpf import bpf, map, bpfglobal, section, compile, compile_to_ir, BPF
from pythonbpf.maps import RingBuf
from ctypes import c_int32, c_void_p
@ -9,17 +9,13 @@ from ctypes import c_int32, c_void_p
def mymap() -> RingBuf:
return RingBuf(max_entries=(1024))
@bpf
@map
def mymap2() -> HashMap:
return HashMap(key=c_int32, value=c_int32, max_entries=1024)
@bpf
@section("tracepoint/syscalls/sys_enter_clone")
def random_section(ctx: c_void_p) -> c_int32:
print("Hello")
e = mymap().reserve(6)
if e:
mymap().submit(e)
return c_int32(0)
@ -33,3 +29,5 @@ compile_to_ir("ringbuf.py", "ringbuf.ll")
compile()
b = BPF()
b.load_and_attach()
while True:
print("running")

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@ -1,369 +0,0 @@
#!/usr/bin/env python3
"""
BTF to Python ctypes Converter
Converts Linux kernel BTF (BPF Type Format) to Python ctypes definitions.
This tool automates the process of:
1. Dumping BTF from vmlinux
2. Preprocessing enum definitions
3. Processing struct kioctx to extract anonymous nested structs
4. Running C preprocessor
5. Converting to Python ctypes using clang2py
6. Post-processing the output
Requirements:
- bpftool
- clang
- ctypeslib2 (pip install ctypeslib2)
"""
import argparse
import os
import re
import subprocess
import sys
import tempfile
class BTFConverter:
def __init__(self, btf_source="/sys/kernel/btf/vmlinux", output_file="vmlinux.py",
keep_intermediate=False, verbose=False):
self.btf_source = btf_source
self.output_file = output_file
self.keep_intermediate = keep_intermediate
self.verbose = verbose
self.temp_dir = tempfile.mkdtemp() if not keep_intermediate else "."
def log(self, message):
"""Print message if verbose mode is enabled."""
if self.verbose:
print(f"[*] {message}")
def run_command(self, cmd, description):
"""Run a shell command and handle errors."""
self.log(f"{description}...")
try:
result = subprocess.run(
cmd,
shell=True,
check=True,
capture_output=True,
text=True
)
if self.verbose and result.stdout:
print(result.stdout)
return result
except subprocess.CalledProcessError as e:
print(f"Error during {description}:", file=sys.stderr)
print(e.stderr, file=sys.stderr)
sys.exit(1)
def step1_dump_btf(self):
"""Step 1: Dump BTF from vmlinux."""
vmlinux_h = os.path.join(self.temp_dir, "vmlinux.h")
cmd = f"bpftool btf dump file {self.btf_source} format c > {vmlinux_h}"
self.run_command(cmd, "Dumping BTF from vmlinux")
return vmlinux_h
def step2_preprocess_enums(self, input_file):
"""Step 1.5: Preprocess enum definitions."""
self.log("Preprocessing enum definitions...")
with open(input_file, 'r') as f:
original_code = f.read()
# Extract anonymous enums
enums = re.findall(
r'(?<!typedef\s)(enum\s*\{[^}]*\})\s*(\w+)\s*(?::\s*\d+)?\s*;',
original_code
)
enum_defs = [enum_block + ';' for enum_block, _ in enums]
# Replace anonymous enums with int declarations
processed_code = re.sub(
r'(?<!typedef\s)enum\s*\{[^}]*\}\s*(\w+)\s*(?::\s*\d+)?\s*;',
r'int \1;',
original_code
)
# Prepend enum definitions
if enum_defs:
enum_text = '\n'.join(enum_defs) + '\n\n'
processed_code = enum_text + processed_code
output_file = os.path.join(self.temp_dir, "vmlinux_processed.h")
with open(output_file, 'w') as f:
f.write(processed_code)
return output_file
def step2_5_process_kioctx(self, input_file):
#TODO: this is a very bad bug and design decision. A single struct has an issue mostly.
"""Step 2.5: Process struct kioctx to extract nested anonymous structs."""
self.log("Processing struct kioctx nested structs...")
with open(input_file, 'r') as f:
content = f.read()
# Pattern to match struct kioctx with its full body (handles multiple nesting levels)
kioctx_pattern = r'struct\s+kioctx\s*\{(?:[^{}]|\{(?:[^{}]|\{[^{}]*\})*\})*\}\s*;'
def process_kioctx_replacement(match):
full_struct = match.group(0)
self.log(f"Found struct kioctx, length: {len(full_struct)} chars")
# Extract the struct body (everything between outermost { and })
body_match = re.search(r'struct\s+kioctx\s*\{(.*)\}\s*;', full_struct, re.DOTALL)
if not body_match:
return full_struct
body = body_match.group(1)
# Find all anonymous structs within the body
# Pattern: struct { ... } followed by ; (not a member name)
anon_struct_pattern = r'struct\s*\{[^}]*\}'
anon_structs = []
anon_counter = 4 # Start from 4, counting down to 1
def replace_anonymous_struct(m):
nonlocal anon_counter
anon_struct_content = m.group(0)
# Extract the body of the anonymous struct
anon_body_match = re.search(r'struct\s*\{(.*)\}', anon_struct_content, re.DOTALL)
if not anon_body_match:
return anon_struct_content
anon_body = anon_body_match.group(1)
# Create the named struct definition
anon_name = f"__anon{anon_counter}"
member_name = f"a{anon_counter}"
# Store the struct definition
anon_structs.append(f"struct {anon_name} {{{anon_body}}};")
anon_counter -= 1
# Return the member declaration
return f"struct {anon_name} {member_name}"
# Process the body, finding and replacing anonymous structs
# We need to be careful to only match anonymous structs followed by ;
processed_body = body
# Find all occurrences and process them
pattern_with_semicolon = r'struct\s*\{([^}]*)\}\s*;'
matches = list(re.finditer(pattern_with_semicolon, body, re.DOTALL))
if not matches:
self.log("No anonymous structs found in kioctx")
return full_struct
self.log(f"Found {len(matches)} anonymous struct(s)")
# Process in reverse order to maintain string positions
for match in reversed(matches):
anon_struct_content = match.group(1)
start_pos = match.start()
end_pos = match.end()
# Create the named struct definition
anon_name = f"__anon{anon_counter}"
member_name = f"a{anon_counter}"
# Store the struct definition
anon_structs.insert(0, f"struct {anon_name} {{{anon_struct_content}}};")
# Replace in the body
replacement = f"struct {anon_name} {member_name};"
processed_body = processed_body[:start_pos] + replacement + processed_body[end_pos:]
anon_counter -= 1
# Rebuild the complete definition
if anon_structs:
# Prepend the anonymous struct definitions
anon_definitions = '\n'.join(anon_structs) + '\n\n'
new_struct = f"struct kioctx {{{processed_body}}};"
return anon_definitions + new_struct
else:
return full_struct
# Apply the transformation
processed_content = re.sub(
kioctx_pattern,
process_kioctx_replacement,
content,
flags=re.DOTALL
)
output_file = os.path.join(self.temp_dir, "vmlinux_kioctx_processed.h")
with open(output_file, 'w') as f:
f.write(processed_content)
self.log(f"Saved kioctx-processed output to {output_file}")
return output_file
def step3_run_preprocessor(self, input_file):
"""Step 2: Run C preprocessor."""
output_file = os.path.join(self.temp_dir, "vmlinux.i")
cmd = f"clang -E {input_file} > {output_file}"
self.run_command(cmd, "Running C preprocessor")
return output_file
def step4_convert_to_ctypes(self, input_file):
"""Step 3: Convert to Python ctypes using clang2py."""
output_file = os.path.join(self.temp_dir, "vmlinux_raw.py")
cmd = (
f"clang2py {input_file} -o {output_file} "
f"--clang-args=\"-fno-ms-extensions -I/usr/include -I/usr/include/linux\""
)
self.run_command(cmd, "Converting to Python ctypes")
return output_file
def step5_postprocess(self, input_file):
"""Step 4: Post-process the generated Python file."""
self.log("Post-processing Python ctypes definitions...")
with open(input_file, "r") as f:
data = f.read()
# Remove lines like ('_45', ctypes.c_int64, 0)
data = re.sub(r"\('_[0-9]+',\s*ctypes\.[a-zA-Z0-9_]+,\s*0\),?\s*\n?", "", data)
# Replace ('_20', ctypes.c_uint64, 64) → ('_20', ctypes.c_uint64)
data = re.sub(r"\('(_[0-9]+)',\s*(ctypes\.[a-zA-Z0-9_]+),\s*[0-9]+\)", r"('\1', \2)", data)
# Replace ('_20', ctypes.c_char, 8) with ('_20', ctypes.c_uint8, 8)
data = re.sub(
r"(ctypes\.c_char)(\s*,\s*\d+\))",
r"ctypes.c_uint8\2",
data
)
# Remove ctypes. prefix from invalid entries
invalid_ctypes = ["bpf_iter_state", "_cache_type", "fs_context_purpose"]
for name in invalid_ctypes:
data = re.sub(rf"\bctypes\.{name}\b", name, data)
with open(self.output_file, "w") as f:
f.write(data)
self.log(f"Saved final output to {self.output_file}")
def cleanup(self):
"""Remove temporary files if not keeping them."""
if not self.keep_intermediate and self.temp_dir != ".":
self.log(f"Cleaning up temporary directory: {self.temp_dir}")
import shutil
shutil.rmtree(self.temp_dir, ignore_errors=True)
def convert(self):
"""Run the complete conversion pipeline."""
try:
self.log("Starting BTF to Python ctypes conversion...")
# Check dependencies
self.check_dependencies()
# Run conversion pipeline
vmlinux_h = self.step1_dump_btf()
vmlinux_processed_h = self.step2_preprocess_enums(vmlinux_h)
vmlinux_kioctx_h = self.step2_5_process_kioctx(vmlinux_processed_h)
vmlinux_i = self.step3_run_preprocessor(vmlinux_kioctx_h)
vmlinux_raw_py = self.step4_convert_to_ctypes(vmlinux_i)
self.step5_postprocess(vmlinux_raw_py)
print(f"\n✓ Conversion complete! Output saved to: {self.output_file}")
except Exception as e:
print(f"\n✗ Error during conversion: {e}", file=sys.stderr)
import traceback
traceback.print_exc()
sys.exit(1)
finally:
self.cleanup()
def check_dependencies(self):
"""Check if required tools are available."""
self.log("Checking dependencies...")
dependencies = {
"bpftool": "bpftool --version",
"clang": "clang --version",
"clang2py": "clang2py --version"
}
missing = []
for tool, cmd in dependencies.items():
try:
subprocess.run(
cmd,
shell=True,
check=True,
capture_output=True
)
except subprocess.CalledProcessError:
missing.append(tool)
if missing:
print("Error: Missing required dependencies:", file=sys.stderr)
for tool in missing:
print(f" - {tool}", file=sys.stderr)
if "clang2py" in missing:
print("\nInstall ctypeslib2: pip install ctypeslib2", file=sys.stderr)
sys.exit(1)
def main():
parser = argparse.ArgumentParser(
description="Convert Linux kernel BTF to Python ctypes definitions",
formatter_class=argparse.RawDescriptionHelpFormatter,
epilog="""
Examples:
%(prog)s
%(prog)s -o kernel_types.py
%(prog)s --btf-source /sys/kernel/btf/custom_module -k -v
"""
)
parser.add_argument(
"--btf-source",
default="/sys/kernel/btf/vmlinux",
help="Path to BTF source (default: /sys/kernel/btf/vmlinux)"
)
parser.add_argument(
"-o", "--output",
default="vmlinux.py",
help="Output Python file (default: vmlinux.py)"
)
parser.add_argument(
"-k", "--keep-intermediate",
action="store_true",
help="Keep intermediate files (vmlinux.h, vmlinux_processed.h, etc.)"
)
parser.add_argument(
"-v", "--verbose",
action="store_true",
help="Enable verbose output"
)
args = parser.parse_args()
converter = BTFConverter(
btf_source=args.btf_source,
output_file=args.output,
keep_intermediate=args.keep_intermediate,
verbose=args.verbose
)
converter.convert()
if __name__ == "__main__":
main()