bpf passthrough gen in codegen

Signed-off-by: varun-r-mallya <varunrmallya@gmail.com>

pyproject.toml

@@ -10,6 +10,20 @@ authors = [
   { name = "r41k0u", email="pragyanshchaturvedi18@gmail.com" },
   { name = "varun-r-mallya", email="varunrmallya@gmail.com" }
 ]
+classifiers = [
+    "Development Status :: 3 - Alpha",
+    "Intended Audience :: Developers",
+    "Operating System :: POSIX :: Linux",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python",
+    "Topic :: Software Development :: Libraries :: Python Modules",
+    "Topic :: System :: Operating System Kernels :: Linux",
+]
 readme = "README.md"
 license = {text = "Apache-2.0"}
 requires-python = ">=3.8"

pythonbpf/allocation_pass.py

@@ -5,6 +5,7 @@ from llvmlite import ir
 from dataclasses import dataclass
 from typing import Any
 from pythonbpf.helper import HelperHandlerRegistry
+from .expr import VmlinuxHandlerRegistry
 from pythonbpf.type_deducer import ctypes_to_ir
 
 logger = logging.getLogger(__name__)
@@ -49,6 +50,15 @@ def handle_assign_allocation(builder, stmt, local_sym_tab, structs_sym_tab):
         logger.debug(f"Variable {var_name} already allocated, skipping")
         return
 
+    # When allocating a variable, check if it's a vmlinux struct type
+    if isinstance(stmt.value, ast.Name) and VmlinuxHandlerRegistry.is_vmlinux_struct(
+        stmt.value.id
+    ):
+        # Handle vmlinux struct allocation
+        # This requires more implementation
+        print(stmt.value)
+        pass
+
     # 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)

pythonbpf/codegen.py

@@ -5,6 +5,8 @@ from .functions import func_proc
 from .maps import maps_proc
 from .structs import structs_proc
 from .vmlinux_parser import vmlinux_proc
+from pythonbpf.vmlinux_parser.vmlinux_exports_handler import VmlinuxHandler
+from .expr import VmlinuxHandlerRegistry
 from .globals_pass import (
     globals_list_creation,
     globals_processing,
@@ -34,6 +36,23 @@ def finalize_module(original_str):
     replacement = r'\1 "btf_ama"'
     return re.sub(pattern, replacement, original_str)
 
+def bpf_passthrough_gen(module):
+    i32_ty = ir.IntType(32)
+    ptr_ty = ir.PointerType(ir.IntType(8))
+    fnty = ir.FunctionType(ptr_ty, [i32_ty, ptr_ty])
+
+    # Declare the intrinsic
+    passthrough = ir.Function(module, fnty, "llvm.bpf.passthrough.p0.p0")
+
+    # Set function attributes
+    # TODO: the ones commented are supposed to be there but cannot be added due to llvmlite limitations at the moment
+    # passthrough.attributes.add("nofree")
+    # passthrough.attributes.add("nosync")
+    passthrough.attributes.add("nounwind")
+    # passthrough.attributes.add("memory(none)")
+
+    return passthrough
+
 
 def find_bpf_chunks(tree):
     """Find all functions decorated with @bpf in the AST."""
@@ -55,11 +74,16 @@ def processor(source_code, filename, module):
     for func_node in bpf_chunks:
         logger.info(f"Found BPF function/struct: {func_node.name}")
 
-    vmlinux_proc(tree, module)
+    bpf_passthrough_gen(module)
+
+    vmlinux_symtab = vmlinux_proc(tree, module)
+    if vmlinux_symtab:
+        handler = VmlinuxHandler.initialize(vmlinux_symtab)
+        VmlinuxHandlerRegistry.set_handler(handler)
+
     populate_global_symbol_table(tree, module)
     license_processing(tree, module)
     globals_processing(tree, module)
-
     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)

pythonbpf/debuginfo/debug_info_generator.py

@@ -81,6 +81,20 @@ class DebugInfoGenerator:
             },
         )
 
+    def create_array_type_vmlinux(self, type_info: Any, count: int) -> Any:
+        """Create an array type of the given base type with specified count"""
+        base_type, type_sizing = type_info
+        subrange = self.module.add_debug_info("DISubrange", {"count": count})
+        return self.module.add_debug_info(
+            "DICompositeType",
+            {
+                "tag": dc.DW_TAG_array_type,
+                "baseType": base_type,
+                "size": type_sizing,
+                "elements": [subrange],
+            },
+        )
+
     @staticmethod
     def _compute_array_size(base_type: Any, count: int) -> int:
         # Extract size from base_type if possible
@@ -101,6 +115,23 @@ class DebugInfoGenerator:
             },
         )
 
+    def create_struct_member_vmlinux(
+        self, name: str, base_type_with_size: Any, offset: int
+    ) -> Any:
+        """Create a struct member with the given name, type, and offset"""
+        base_type, type_size = base_type_with_size
+        return self.module.add_debug_info(
+            "DIDerivedType",
+            {
+                "tag": dc.DW_TAG_member,
+                "name": name,
+                "file": self.module._file_metadata,
+                "baseType": base_type,
+                "size": type_size,
+                "offset": offset,
+            },
+        )
+
     def create_struct_type(
         self, members: List[Any], size: int, is_distinct: bool
     ) -> Any:
@@ -116,6 +147,22 @@ class DebugInfoGenerator:
             is_distinct=is_distinct,
         )
 
+    def create_struct_type_with_name(
+        self, name: str, members: List[Any], size: int, is_distinct: bool
+    ) -> Any:
+        """Create a struct type with the given members and size"""
+        return self.module.add_debug_info(
+            "DICompositeType",
+            {
+                "name": name,
+                "tag": dc.DW_TAG_structure_type,
+                "file": self.module._file_metadata,
+                "size": size,
+                "elements": members,
+            },
+            is_distinct=is_distinct,
+        )
+
     def create_global_var_debug_info(
         self, name: str, var_type: Any, is_local: bool = False
     ) -> Any:

pythonbpf/expr/__init__.py

@@ -2,6 +2,7 @@ from .expr_pass import eval_expr, handle_expr, get_operand_value
 from .type_normalization import convert_to_bool, get_base_type_and_depth
 from .ir_ops import deref_to_depth
 from .call_registry import CallHandlerRegistry
+from .vmlinux_registry import VmlinuxHandlerRegistry
 
 __all__ = [
     "eval_expr",
@@ -11,4 +12,5 @@ __all__ = [
     "deref_to_depth",
     "get_operand_value",
     "CallHandlerRegistry",
+    "VmlinuxHandlerRegistry",
 ]

pythonbpf/expr/expr_pass.py

@@ -12,6 +12,7 @@ from .type_normalization import (
     get_base_type_and_depth,
     deref_to_depth,
 )
+from .vmlinux_registry import VmlinuxHandlerRegistry
 
 logger: Logger = logging.getLogger(__name__)
 
@@ -27,8 +28,12 @@ def _handle_name_expr(expr: ast.Name, local_sym_tab: Dict, builder: ir.IRBuilder
         val = builder.load(var)
         return val, local_sym_tab[expr.id].ir_type
     else:
-        logger.info(f"Undefined variable {expr.id}")
-        return None
+        # Check if it's a vmlinux enum/constant
+        vmlinux_result = VmlinuxHandlerRegistry.handle_name(expr.id)
+        if vmlinux_result is not None:
+            return vmlinux_result
+
+        raise SyntaxError(f"Undefined variable {expr.id}")
 
 
 def _handle_constant_expr(module, builder, expr: ast.Constant):
@@ -74,6 +79,13 @@ def _handle_attribute_expr(
                 val = builder.load(gep)
                 field_type = metadata.field_type(attr_name)
                 return val, field_type
+
+        # Try vmlinux handler as fallback
+        vmlinux_result = VmlinuxHandlerRegistry.handle_attribute(
+            expr, local_sym_tab, None, builder
+        )
+        if vmlinux_result is not None:
+            return vmlinux_result
     return None
 
 
@@ -130,7 +142,12 @@ def get_operand_value(
             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}")
+        else:
+            # Check if it's a vmlinux enum/constant
+            vmlinux_result = VmlinuxHandlerRegistry.handle_name(operand.id)
+            if vmlinux_result is not None:
+                val, _ = vmlinux_result
+                return val
     elif isinstance(operand, ast.Constant):
         if isinstance(operand.value, int):
             cst = ir.Constant(ir.IntType(64), int(operand.value))
@@ -332,6 +349,7 @@ def _handle_unary_op(
         neg_one = ir.Constant(ir.IntType(64), -1)
         result = builder.mul(operand, neg_one)
         return result, ir.IntType(64)
+    return None
 
 
 # ============================================================================

pythonbpf/expr/vmlinux_registry.py

@@ -0,0 +1,45 @@
+import ast
+
+
+class VmlinuxHandlerRegistry:
+    """Registry for vmlinux handler operations"""
+
+    _handler = None
+
+    @classmethod
+    def set_handler(cls, handler):
+        """Set the vmlinux handler"""
+        cls._handler = handler
+
+    @classmethod
+    def get_handler(cls):
+        """Get the vmlinux handler"""
+        return cls._handler
+
+    @classmethod
+    def handle_name(cls, name):
+        """Try to handle a name as vmlinux enum/constant"""
+        if cls._handler is None:
+            return None
+        return cls._handler.handle_vmlinux_enum(name)
+
+    @classmethod
+    def handle_attribute(cls, expr, local_sym_tab, module, builder):
+        """Try to handle an attribute access as vmlinux struct field"""
+        if cls._handler is None:
+            return None
+
+        if isinstance(expr.value, ast.Name):
+            var_name = expr.value.id
+            field_name = expr.attr
+            return cls._handler.handle_vmlinux_struct_field(
+                var_name, field_name, module, builder, local_sym_tab
+            )
+        return None
+
+    @classmethod
+    def is_vmlinux_struct(cls, name):
+        """Check if a name refers to a vmlinux struct"""
+        if cls._handler is None:
+            return False
+        return cls._handler.is_vmlinux_struct(name)

pythonbpf/functions/functions_pass.py

@@ -311,7 +311,13 @@ def process_stmt(
 
 
 def process_func_body(
-    module, builder, func_node, func, ret_type, map_sym_tab, structs_sym_tab
+    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
@@ -384,7 +390,13 @@ def process_bpf_chunk(func_node, module, return_type, map_sym_tab, structs_sym_t
     builder = ir.IRBuilder(block)
 
     process_func_body(
-        module, builder, func_node, func, ret_type, map_sym_tab, structs_sym_tab
+        module,
+        builder,
+        func_node,
+        func,
+        ret_type,
+        map_sym_tab,
+        structs_sym_tab,
     )
     return func
 

pythonbpf/helper/printk_formatter.py

@@ -3,6 +3,7 @@ import logging
 
 from llvmlite import ir
 from pythonbpf.expr import eval_expr, get_base_type_and_depth, deref_to_depth
+from pythonbpf.expr.vmlinux_registry import VmlinuxHandlerRegistry
 
 logger = logging.getLogger(__name__)
 
@@ -108,6 +109,16 @@ def _process_name_in_fval(name_node, fmt_parts, exprs, local_sym_tab):
     if local_sym_tab and name_node.id in local_sym_tab:
         _, var_type, tmp = local_sym_tab[name_node.id]
         _populate_fval(var_type, name_node, fmt_parts, exprs)
+    else:
+        # Try to resolve through vmlinux registry if not in local symbol table
+        result = VmlinuxHandlerRegistry.handle_name(name_node.id)
+        if result:
+            val, var_type = result
+            _populate_fval(var_type, name_node, fmt_parts, exprs)
+        else:
+            raise ValueError(
+                f"Variable '{name_node.id}' not found in symbol table or vmlinux"
+            )
 
 
 def _process_attr_in_fval(attr_node, fmt_parts, exprs, local_sym_tab, struct_sym_tab):

pythonbpf/maps/maps_pass.py

@@ -6,6 +6,8 @@ from llvmlite import ir
 from .maps_utils import MapProcessorRegistry
 from .map_types import BPFMapType
 from .map_debug_info import create_map_debug_info, create_ringbuf_debug_info
+from pythonbpf.expr.vmlinux_registry import VmlinuxHandlerRegistry
+
 
 logger: Logger = logging.getLogger(__name__)
 
@@ -51,7 +53,7 @@ def _parse_map_params(rval, expected_args=None):
     """Parse map parameters from call arguments and keywords."""
 
     params = {}
-
+    handler = VmlinuxHandlerRegistry.get_handler()
     # Parse positional arguments
     if expected_args:
         for i, arg_name in enumerate(expected_args):
@@ -65,7 +67,12 @@ def _parse_map_params(rval, expected_args=None):
     # Parse keyword arguments (override positional)
     for keyword in rval.keywords:
         if isinstance(keyword.value, ast.Name):
-            params[keyword.arg] = keyword.value.id
+            name = keyword.value.id
+            if handler and handler.is_vmlinux_enum(name):
+                result = handler.get_vmlinux_enum_value(name)
+                params[keyword.arg] = result if result is not None else name
+            else:
+                params[keyword.arg] = name
         elif isinstance(keyword.value, ast.Constant):
             params[keyword.arg] = keyword.value.value
 

pythonbpf/vmlinux_parser/assignment_info.py

@@ -0,0 +1,36 @@
+from enum import Enum, auto
+from typing import Any, Dict, List, Optional, TypedDict
+from dataclasses import dataclass
+import llvmlite.ir as ir
+
+from pythonbpf.vmlinux_parser.dependency_node import Field
+
+
+@dataclass
+class AssignmentType(Enum):
+    CONSTANT = auto()
+    STRUCT = auto()
+    ARRAY = auto()  # probably won't be used
+    FUNCTION_POINTER = auto()
+    POINTER = auto()  # again, probably won't be used
+
+
+@dataclass
+class FunctionSignature(TypedDict):
+    return_type: str
+    param_types: List[str]
+    varargs: bool
+
+
+# Thew name of the assignment will be in the dict that uses this class
+@dataclass
+class AssignmentInfo(TypedDict):
+    value_type: AssignmentType
+    python_type: type
+    value: Optional[Any]
+    pointer_level: Optional[int]
+    signature: Optional[FunctionSignature]  # For function pointers
+    # The key of the dict is the name of the field.
+    #   Value is a tuple that contains the global variable representing that field
+    #   along with all the information about that field as a Field type.
+    members: Optional[Dict[str, tuple[ir.GlobalVariable, Field]]]  # For structs.

pythonbpf/vmlinux_parser/class_handler.py

@@ -1,6 +1,7 @@
 import logging
 from functools import lru_cache
 import importlib
+
 from .dependency_handler import DependencyHandler
 from .dependency_node import DependencyNode
 import ctypes
@@ -15,7 +16,11 @@ def get_module_symbols(module_name: str):
     return [name for name in dir(imported_module)], imported_module
 
 
-def process_vmlinux_class(node, llvm_module, handler: DependencyHandler):
+def process_vmlinux_class(
+    node,
+    llvm_module,
+    handler: DependencyHandler,
+):
     symbols_in_module, imported_module = get_module_symbols("vmlinux")
     if node.name in symbols_in_module:
         vmlinux_type = getattr(imported_module, node.name)
@@ -25,7 +30,10 @@ def process_vmlinux_class(node, llvm_module, handler: DependencyHandler):
 
 
 def process_vmlinux_post_ast(
-    elem_type_class, llvm_handler, handler: DependencyHandler, processing_stack=None
+    elem_type_class,
+    llvm_handler,
+    handler: DependencyHandler,
+    processing_stack=None,
 ):
     # Initialize processing stack on first call
     if processing_stack is None:
@@ -46,7 +54,7 @@ def process_vmlinux_post_ast(
         logger.debug(f"Node {current_symbol_name} already processed and ready")
         return True
 
-    # XXX:Check it's use. It's probably not being used.
+    # XXX:Check its use. It's probably not being used.
     if current_symbol_name in processing_stack:
         logger.debug(
             f"Dependency already in processing stack for {current_symbol_name}, skipping"
@@ -98,12 +106,47 @@ def process_vmlinux_post_ast(
                 [elem_type, elem_bitfield_size] = elem_temp_list
                 local_module_name = getattr(elem_type, "__module__", None)
                 new_dep_node.add_field(elem_name, elem_type, ready=False)
+
                 if local_module_name == ctypes.__name__:
+                    # TODO: need to process pointer to ctype and also CFUNCTYPES here recursively. Current processing is a single dereference
                     new_dep_node.set_field_bitfield_size(elem_name, elem_bitfield_size)
-                    new_dep_node.set_field_ready(elem_name, is_ready=True)
-                    logger.debug(
-                        f"Field {elem_name} is direct ctypes type: {elem_type}"
-                    )
+
+                    # Process pointer to ctype
+                    if isinstance(elem_type, type) and issubclass(
+                        elem_type, ctypes._Pointer
+                    ):
+                        # Get the pointed-to type
+                        pointed_type = elem_type._type_
+                        logger.debug(f"Found pointer to type: {pointed_type}")
+                        new_dep_node.set_field_containing_type(elem_name, pointed_type)
+                        new_dep_node.set_field_ctype_complex_type(
+                            elem_name, ctypes._Pointer
+                        )
+                        new_dep_node.set_field_ready(elem_name, is_ready=True)
+
+                    # Process function pointers (CFUNCTYPE)
+                    elif hasattr(elem_type, "_restype_") and hasattr(
+                        elem_type, "_argtypes_"
+                    ):
+                        # This is a CFUNCTYPE or similar
+                        logger.info(
+                            f"Function pointer detected for {elem_name} with return type {elem_type._restype_} and arguments {elem_type._argtypes_}"
+                        )
+                        # Set the field as ready but mark it with special handling
+                        new_dep_node.set_field_ctype_complex_type(
+                            elem_name, ctypes.CFUNCTYPE
+                        )
+                        new_dep_node.set_field_ready(elem_name, is_ready=True)
+                        logger.warning(
+                            "Blindly processing CFUNCTYPE ctypes to ensure compilation. Unsupported"
+                        )
+
+                    else:
+                        # Regular ctype
+                        new_dep_node.set_field_ready(elem_name, is_ready=True)
+                        logger.debug(
+                            f"Field {elem_name} is direct ctypes type: {elem_type}"
+                        )
                 elif local_module_name == "vmlinux":
                     new_dep_node.set_field_bitfield_size(elem_name, elem_bitfield_size)
                     logger.debug(
@@ -127,6 +170,10 @@ def process_vmlinux_post_ast(
                                     ctype_complex_type = ctypes.Array
                                 elif issubclass(elem_type, ctypes._Pointer):
                                     ctype_complex_type = ctypes._Pointer
+                                else:
+                                    raise ImportError(
+                                        "Non Array and Pointer type ctype imports not supported in current version"
+                                    )
                             else:
                                 raise TypeError("Unsupported ctypes subclass")
                         else:
@@ -188,7 +235,10 @@ def process_vmlinux_post_ast(
                             else str(elem_type)
                         )
                         process_vmlinux_post_ast(
-                            elem_type, llvm_handler, handler, processing_stack
+                            elem_type,
+                            llvm_handler,
+                            handler,
+                            processing_stack,
                         )
                         new_dep_node.set_field_ready(elem_name, True)
                 else:
@@ -199,7 +249,7 @@ def process_vmlinux_post_ast(
     else:
         raise ImportError("UNSUPPORTED Module")
 
-    logging.info(
+    logger.info(
         f"{current_symbol_name} processed and handler readiness {handler.is_ready}"
     )
     return True

pythonbpf/vmlinux_parser/dependency_node.py

@@ -18,6 +18,31 @@ class Field:
     value: Any = None
     ready: bool = False
 
+    def __hash__(self):
+        """
+        Create a hash based on the immutable attributes that define this field's identity.
+        This allows Field objects to be used as dictionary keys.
+        """
+        # Use a tuple of the fields that uniquely identify this field
+        identity = (
+            self.name,
+            id(self.type),  # Use id for non-hashable types
+            id(self.ctype_complex_type) if self.ctype_complex_type else None,
+            id(self.containing_type) if self.containing_type else None,
+            self.type_size,
+            self.bitfield_size,
+            self.offset,
+            self.value if self.value else None,
+        )
+        return hash(identity)
+
+    def __eq__(self, other):
+        """
+        Define equality consistent with the hash function.
+        Two fields are equal if they have they are the same
+        """
+        return self is other
+
     def set_ready(self, is_ready: bool = True) -> None:
         """Set the readiness state of this field."""
         self.ready = is_ready

pythonbpf/vmlinux_parser/import_detector.py

@@ -1,9 +1,10 @@
 import ast
 import logging
-from typing import List, Tuple, Any
 import importlib
 import inspect
+import llvmlite.ir as ir
 
+from .assignment_info import AssignmentInfo, AssignmentType
 from .dependency_handler import DependencyHandler
 from .ir_gen import IRGenerator
 from .class_handler import process_vmlinux_class
@@ -11,7 +12,7 @@ from .class_handler import process_vmlinux_class
 logger = logging.getLogger(__name__)
 
 
-def detect_import_statement(tree: ast.AST) -> List[Tuple[str, ast.ImportFrom]]:
+def detect_import_statement(tree: ast.AST) -> list[tuple[str, ast.ImportFrom]]:
     """
     Parse AST and detect import statements from vmlinux.
 
@@ -82,23 +83,23 @@ def vmlinux_proc(tree: ast.AST, module):
     # initialise dependency handler
     handler = DependencyHandler()
     # initialise assignment dictionary of name to type
-    assignments: dict[str, tuple[type, Any]] = {}
+    assignments: dict[str, AssignmentInfo] = {}
 
     if not import_statements:
         logger.info("No vmlinux imports found")
-        return
+        return None
 
     # Import vmlinux module directly
     try:
         vmlinux_mod = importlib.import_module("vmlinux")
     except ImportError:
         logger.warning("Could not import vmlinux module")
-        return
+        return None
 
     source_file = inspect.getsourcefile(vmlinux_mod)
     if source_file is None:
         logger.warning("Cannot find source for vmlinux module")
-        return
+        return None
 
     with open(source_file, "r") as f:
         mod_ast = ast.parse(f.read(), filename=source_file)
@@ -128,20 +129,35 @@ def vmlinux_proc(tree: ast.AST, module):
                     f"{imported_name} not found as ClassDef or Assign in vmlinux"
                 )
 
-    IRGenerator(module, handler)
+    IRGenerator(module, handler, assignments)
     return assignments
 
 
-def process_vmlinux_assign(node, module, assignments: dict[str, tuple[type, Any]]):
-    # Check if this is a simple assignment with a constant value
+def process_vmlinux_assign(node, module, assignments: dict[str, AssignmentInfo]):
+    """Process assignments from vmlinux module."""
+    # Only handle single-target assignments
     if len(node.targets) == 1 and isinstance(node.targets[0], ast.Name):
         target_name = node.targets[0].id
+
+        # Handle constant value assignments
         if isinstance(node.value, ast.Constant):
-            assignments[target_name] = (type(node.value.value), node.value.value)
+            # Fixed: using proper TypedDict creation syntax with named arguments
+            assignments[target_name] = AssignmentInfo(
+                value_type=AssignmentType.CONSTANT,
+                python_type=type(node.value.value),
+                value=node.value.value,
+                pointer_level=None,
+                signature=None,
+                members=None,
+            )
             logger.info(
                 f"Added assignment: {target_name} = {node.value.value!r} of type {type(node.value.value)}"
             )
+
+        # Handle other assignment types that we may need to support
         else:
-            raise ValueError(f"Unsupported assignment type for {target_name}")
+            logger.warning(
+                f"Unsupported assignment type for {target_name}: {ast.dump(node.value)}"
+            )
     else:
         raise ValueError("Not a simple assignment")

pythonbpf/vmlinux_parser/ir_gen/debug_info_gen.py

@@ -1,15 +1,161 @@
-from pythonbpf.debuginfo import DebugInfoGenerator
+from pythonbpf.debuginfo import DebugInfoGenerator, dwarf_constants as dc
+from ..dependency_node import DependencyNode
+import ctypes
+import logging
+from typing import List, Any, Tuple
+
+logger = logging.getLogger(__name__)
 
 
-def debug_info_generation(struct, llvm_module):
+def debug_info_generation(
+    struct: DependencyNode,
+    llvm_module,
+    generated_debug_info: List[Tuple[DependencyNode, Any]],
+) -> Any:
+    """
+    Generate DWARF debug information for a struct defined in a DependencyNode.
+
+    Args:
+        struct: The dependency node containing struct information
+        llvm_module: The LLVM module to add debug info to
+        generated_debug_info: List of tuples (struct, debug_info) to track generated debug info
+
+    Returns:
+        The generated global variable debug info
+    """
+    # Set up debug info generator
     generator = DebugInfoGenerator(llvm_module)
-    # this is sample debug info generation
-    # i64type = generator.get_uint64_type()
 
-    struct_type = generator.create_struct_type([], 64 * 4, is_distinct=True)
+    # Check if debug info for this struct has already been generated
+    for existing_struct, debug_info in generated_debug_info:
+        if existing_struct.name == struct.name:
+            return debug_info
 
-    global_var = generator.create_global_var_debug_info(
-        struct.name, struct_type, is_local=False
+    # Process all fields and create members for the struct
+    members = []
+    for field_name, field in struct.fields.items():
+        # Get appropriate debug type for this field
+        field_type = _get_field_debug_type(
+            field_name, field, generator, struct, generated_debug_info
+        )
+        # Create struct member with proper offset
+        member = generator.create_struct_member_vmlinux(
+            field_name, field_type, field.offset * 8
+        )
+        members.append(member)
+
+    if struct.name.startswith("struct_"):
+        struct_name = struct.name.removeprefix("struct_")
+    else:
+        raise ValueError("Unions are not supported in the current version")
+    # Create struct type with all members
+    struct_type = generator.create_struct_type_with_name(
+        struct_name, members, struct.__sizeof__() * 8, is_distinct=True
     )
 
-    return global_var
+    return struct_type
+
+
+def _get_field_debug_type(
+    field_name: str,
+    field,
+    generator: DebugInfoGenerator,
+    parent_struct: DependencyNode,
+    generated_debug_info: List[Tuple[DependencyNode, Any]],
+) -> tuple[Any, int]:
+    """
+    Determine the appropriate debug type for a field based on its Python/ctypes type.
+
+    Args:
+        field_name: Name of the field
+        field: Field object containing type information
+        generator: DebugInfoGenerator instance
+        parent_struct: The parent struct containing this field
+        generated_debug_info: List of already generated debug info
+
+    Returns:
+        The debug info type for this field
+    """
+    # Handle complex types (arrays, pointers)
+    if field.ctype_complex_type is not None:
+        if issubclass(field.ctype_complex_type, ctypes.Array):
+            # Handle array types
+            element_type, base_type_size = _get_basic_debug_type(
+                field.containing_type, generator
+            )
+            return generator.create_array_type_vmlinux(
+                (element_type, base_type_size * field.type_size), field.type_size
+            ), field.type_size * base_type_size
+        elif issubclass(field.ctype_complex_type, ctypes._Pointer):
+            # Handle pointer types
+            pointee_type, _ = _get_basic_debug_type(field.containing_type, generator)
+            return generator.create_pointer_type(pointee_type), 64
+
+    # Handle other vmlinux types (nested structs)
+    if field.type.__module__ == "vmlinux":
+        # If it's a struct from vmlinux, check if we've already generated debug info for it
+        struct_name = field.type.__name__
+
+        # Look for existing debug info in the list
+        for existing_struct, debug_info in generated_debug_info:
+            if existing_struct.name == struct_name:
+                # Use existing debug info
+                return debug_info, existing_struct.__sizeof__()
+
+        # If not found, create a forward declaration
+        # This will be completed when the actual struct is processed
+        logger.warning("Forward declaration in struct created")
+        forward_type = generator.create_struct_type([], 0, is_distinct=True)
+        return forward_type, 0
+
+    # Handle basic C types
+    return _get_basic_debug_type(field.type, generator)
+
+
+def _get_basic_debug_type(ctype, generator: DebugInfoGenerator) -> Any:
+    """
+    Map a ctypes type to a DWARF debug type.
+
+    Args:
+        ctype: A ctypes type or Python type
+        generator: DebugInfoGenerator instance
+
+    Returns:
+        The corresponding debug type
+    """
+    # Map ctypes to debug info types
+    if ctype == ctypes.c_char or ctype == ctypes.c_byte:
+        return generator.get_basic_type("char", 8, dc.DW_ATE_signed_char), 8
+    elif ctype == ctypes.c_ubyte or ctype == ctypes.c_uint8:
+        return generator.get_basic_type("unsigned char", 8, dc.DW_ATE_unsigned_char), 8
+    elif ctype == ctypes.c_short or ctype == ctypes.c_int16:
+        return generator.get_basic_type("short", 16, dc.DW_ATE_signed), 16
+    elif ctype == ctypes.c_ushort or ctype == ctypes.c_uint16:
+        return generator.get_basic_type("unsigned short", 16, dc.DW_ATE_unsigned), 16
+    elif ctype == ctypes.c_int or ctype == ctypes.c_int32:
+        return generator.get_basic_type("int", 32, dc.DW_ATE_signed), 32
+    elif ctype == ctypes.c_uint or ctype == ctypes.c_uint32:
+        return generator.get_basic_type("unsigned int", 32, dc.DW_ATE_unsigned), 32
+    elif ctype == ctypes.c_long:
+        return generator.get_basic_type("long", 64, dc.DW_ATE_signed), 64
+    elif ctype == ctypes.c_ulong:
+        return generator.get_basic_type("unsigned long", 64, dc.DW_ATE_unsigned), 64
+    elif ctype == ctypes.c_longlong or ctype == ctypes.c_int64:
+        return generator.get_basic_type("long long", 64, dc.DW_ATE_signed), 64
+    elif ctype == ctypes.c_ulonglong or ctype == ctypes.c_uint64:
+        return generator.get_basic_type(
+            "unsigned long long", 64, dc.DW_ATE_unsigned
+        ), 64
+    elif ctype == ctypes.c_float:
+        return generator.get_basic_type("float", 32, dc.DW_ATE_float), 32
+    elif ctype == ctypes.c_double:
+        return generator.get_basic_type("double", 64, dc.DW_ATE_float), 64
+    elif ctype == ctypes.c_bool:
+        return generator.get_basic_type("bool", 8, dc.DW_ATE_boolean), 8
+    elif ctype == ctypes.c_char_p:
+        char_type = generator.get_basic_type("char", 8, dc.DW_ATE_signed_char), 8
+        return generator.create_pointer_type(char_type)
+    elif ctype == ctypes.c_void_p:
+        return generator.create_pointer_type(None), 64
+    else:
+        return generator.get_uint64_type(), 64

pythonbpf/vmlinux_parser/ir_gen/ir_generation.py

@@ -1,5 +1,7 @@
 import ctypes
 import logging
+
+from ..assignment_info import AssignmentInfo, AssignmentType
 from ..dependency_handler import DependencyHandler
 from .debug_info_gen import debug_info_generation
 from ..dependency_node import DependencyNode
@@ -10,10 +12,14 @@ logger = logging.getLogger(__name__)
 
 class IRGenerator:
     # get the assignments dict and add this stuff to it.
-    def __init__(self, llvm_module, handler: DependencyHandler, assignment=None):
+    def __init__(self, llvm_module, handler: DependencyHandler, assignments):
         self.llvm_module = llvm_module
         self.handler: DependencyHandler = handler
         self.generated: list[str] = []
+        self.generated_debug_info: list = []
+        # Use struct_name and field_name as key instead of Field object
+        self.generated_field_names: dict[str, dict[str, ir.GlobalVariable]] = {}
+        self.assignments: dict[str, AssignmentInfo] = assignments
         if not handler.is_ready:
             raise ImportError(
                 "Semantic analysis of vmlinux imports failed. Cannot generate IR"
@@ -66,20 +72,61 @@ class IRGenerator:
                                 f"Warning: Dependency {dependency} not found in handler"
                             )
 
-            # Actual processor logic here after dependencies are resolved
-            self.gen_ir(struct)
+            # Generate IR first to populate field names
+            self.generated_debug_info.append(
+                (struct, self.gen_ir(struct, self.generated_debug_info))
+            )
+
+            # Fill the assignments dictionary with struct information
+            if struct.name not in self.assignments:
+                # Create a members dictionary for AssignmentInfo
+                members_dict = {}
+                for field_name, field in struct.fields.items():
+                    # Get the generated field name from our dictionary, or use field_name if not found
+                    if (
+                        struct.name in self.generated_field_names
+                        and field_name in self.generated_field_names[struct.name]
+                    ):
+                        field_global_variable = self.generated_field_names[struct.name][
+                            field_name
+                        ]
+                        members_dict[field_name] = (field_global_variable, field)
+                    else:
+                        raise ValueError(
+                            f"llvm global name not found for struct field {field_name}"
+                        )
+                        # members_dict[field_name] = (field_name, field)
+
+                # Add struct to assignments dictionary
+                self.assignments[struct.name] = AssignmentInfo(
+                    value_type=AssignmentType.STRUCT,
+                    python_type=struct.ctype_struct,
+                    value=None,
+                    pointer_level=None,
+                    signature=None,
+                    members=members_dict,
+                )
+                logger.info(f"Added struct assignment info for {struct.name}")
+
             self.generated.append(struct.name)
 
         finally:
             # Remove from processing stack after we're done
             processing_stack.discard(struct.name)
 
-    def gen_ir(self, struct):
+    def gen_ir(self, struct, generated_debug_info):
         # TODO: we add the btf_ama attribute by monkey patching in the end of compilation, but once llvmlite
         #  accepts our issue, we will resort to normal accessed attribute based attribute addition
         # currently we generate all possible field accesses for CO-RE and put into the assignment table
-        debug_info = debug_info_generation(struct, self.llvm_module)
+        debug_info = debug_info_generation(
+            struct, self.llvm_module, generated_debug_info
+        )
         field_index = 0
+
+        # Make sure the struct has an entry in our field names dictionary
+        if struct.name not in self.generated_field_names:
+            self.generated_field_names[struct.name] = {}
+
         for field_name, field in struct.fields.items():
             # does not take arrays and similar types into consideration yet.
             if field.ctype_complex_type is not None and issubclass(
@@ -89,6 +136,18 @@ class IRGenerator:
                 containing_type = field.containing_type
                 if containing_type.__module__ == ctypes.__name__:
                     containing_type_size = ctypes.sizeof(containing_type)
+                    if array_size == 0:
+                        field_co_re_name = self._struct_name_generator(
+                            struct, field, field_index, True, 0, containing_type_size
+                        )
+                        globvar = ir.GlobalVariable(
+                            self.llvm_module, ir.IntType(64), name=field_co_re_name
+                        )
+                        globvar.linkage = "external"
+                        globvar.set_metadata("llvm.preserve.access.index", debug_info)
+                        self.generated_field_names[struct.name][field_name] = globvar
+                        field_index += 1
+                        continue
                     for i in range(0, array_size):
                         field_co_re_name = self._struct_name_generator(
                             struct, field, field_index, True, i, containing_type_size
@@ -98,6 +157,7 @@ class IRGenerator:
                         )
                         globvar.linkage = "external"
                         globvar.set_metadata("llvm.preserve.access.index", debug_info)
+                        self.generated_field_names[struct.name][field_name] = globvar
                     field_index += 1
             elif field.type_size is not None:
                 array_size = field.type_size
@@ -115,6 +175,7 @@ class IRGenerator:
                         )
                         globvar.linkage = "external"
                         globvar.set_metadata("llvm.preserve.access.index", debug_info)
+                        self.generated_field_names[struct.name][field_name] = globvar
                     field_index += 1
             else:
                 field_co_re_name = self._struct_name_generator(
@@ -126,6 +187,8 @@ class IRGenerator:
                 )
                 globvar.linkage = "external"
                 globvar.set_metadata("llvm.preserve.access.index", debug_info)
+                self.generated_field_names[struct.name][field_name] = globvar
+        return debug_info
 
     def _struct_name_generator(
         self,
@@ -136,6 +199,7 @@ class IRGenerator:
         index: int = 0,
         containing_type_size: int = 0,
     ) -> str:
+        # TODO: Does not support Unions as well as recursive pointer and array type naming
         if is_indexed:
             name = (
                 "llvm."

pythonbpf/vmlinux_parser/vmlinux_exports_handler.py

@@ -0,0 +1,90 @@
+import logging
+from llvmlite import ir
+
+from pythonbpf.vmlinux_parser.assignment_info import AssignmentType
+
+logger = logging.getLogger(__name__)
+
+
+class VmlinuxHandler:
+    """Handler for vmlinux-related operations"""
+
+    _instance = None
+
+    @classmethod
+    def get_instance(cls):
+        """Get the singleton instance"""
+        if cls._instance is None:
+            logger.warning("VmlinuxHandler used before initialization")
+            return None
+        return cls._instance
+
+    @classmethod
+    def initialize(cls, vmlinux_symtab):
+        """Initialize the handler with vmlinux symbol table"""
+        cls._instance = cls(vmlinux_symtab)
+        return cls._instance
+
+    def __init__(self, vmlinux_symtab):
+        """Initialize with vmlinux symbol table"""
+        self.vmlinux_symtab = vmlinux_symtab
+        logger.info(
+            f"VmlinuxHandler initialized with {len(vmlinux_symtab) if vmlinux_symtab else 0} symbols"
+        )
+
+    def is_vmlinux_enum(self, name):
+        """Check if name is a vmlinux enum constant"""
+        return (
+            name in self.vmlinux_symtab
+            and self.vmlinux_symtab[name]["value_type"] == AssignmentType.CONSTANT
+        )
+
+    def is_vmlinux_struct(self, name):
+        """Check if name is a vmlinux struct"""
+        return (
+            name in self.vmlinux_symtab
+            and self.vmlinux_symtab[name]["value_type"] == AssignmentType.STRUCT
+        )
+
+    def handle_vmlinux_enum(self, name):
+        """Handle vmlinux enum constants by returning LLVM IR constants"""
+        if self.is_vmlinux_enum(name):
+            value = self.vmlinux_symtab[name]["value"]
+            logger.info(f"Resolving vmlinux enum {name} = {value}")
+            return ir.Constant(ir.IntType(64), value), ir.IntType(64)
+        return None
+
+    def get_vmlinux_enum_value(self, name):
+        """Handle vmlinux enum constants by returning LLVM IR constants"""
+        if self.is_vmlinux_enum(name):
+            value = self.vmlinux_symtab[name]["value"]
+            logger.info(f"The value of vmlinux enum {name} = {value}")
+            return value
+        return None
+
+    def handle_vmlinux_struct(self, struct_name, module, builder):
+        """Handle vmlinux struct initializations"""
+        if self.is_vmlinux_struct(struct_name):
+            # TODO: Implement core-specific struct handling
+            # This will be more complex and depends on the BTF information
+            logger.info(f"Handling vmlinux struct {struct_name}")
+            # Return struct type and allocated pointer
+            # This is a stub, actual implementation will be more complex
+            return None
+        return None
+
+    def handle_vmlinux_struct_field(
+        self, struct_var_name, field_name, module, builder, local_sym_tab
+    ):
+        """Handle access to vmlinux struct fields"""
+        # Check if it's a variable of vmlinux struct type
+        if struct_var_name in local_sym_tab:
+            var_info = local_sym_tab[struct_var_name]  # noqa: F841
+            # Need to check if this variable is a vmlinux struct
+            # This will depend on how you track vmlinux struct types in your symbol table
+            logger.info(
+                f"Attempting to access field {field_name} of possible vmlinux struct {struct_var_name}"
+            )
+            # Return pointer to field and field type
+            return None
+        return None

tests/c-form/ex5.bpf.c

@@ -1,25 +0,0 @@
-#define __TARGET_ARCH_arm64
-
-#include "vmlinux.h"
-#include <bpf/bpf_helpers.h>
-#include <bpf/bpf_tracing.h>
-#include <bpf/bpf_core_read.h>
-
-// Map: key = struct request*, value = u64 timestamp
-struct {
-    __uint(type, BPF_MAP_TYPE_HASH);
-    __type(key, struct request *);
-    __type(value, u64);
-    __uint(max_entries, 1024);
-} start SEC(".maps");
-
-// Attach to kprobe for blk_start_request
-SEC("kprobe/blk_start_request")
-int BPF_KPROBE(trace_start, struct request *req)
-{
-    u64 ts = bpf_ktime_get_ns();
-    bpf_map_update_elem(&start, &req, &ts, BPF_ANY);
-    return 0;
-}
-
-char LICENSE[] SEC("license") = "GPL";

tests/c-form/ex7.bpf.c

@@ -19,7 +19,7 @@ struct {
 SEC("tp/syscalls/sys_enter_setuid")
 int handle_setuid_entry(struct trace_event_raw_sys_enter *ctx) {
   struct event data = {};
-
+  struct blk_integrity_iter it = {};
   // Extract UID from the syscall arguments
   data.uid = (unsigned int)ctx->args[0];
   data.ts = bpf_ktime_get_ns();

tests/c-form/struct_field_tests.bpf.c

@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+/*
+Information gained from reversing this (multiple kernel versions):
+There is no point of
+```llvm
+ tail call void @llvm.dbg.value(metadata ptr %0, metadata !60, metadata !DIExpression()), !dbg !70
+ ```
+ and the first argument of passthrough is fucking useless. It just needs to be a distinct integer:
+ ```llvm
+   %9 = tail call ptr @llvm.bpf.passthrough.p0.p0(i32 3, ptr %8)
+ ```
+*/
+
+SEC("tp/syscalls/sys_enter_execve")
+int handle_setuid_entry(struct trace_event_raw_sys_enter *ctx) {
+  // Access each argument separately with clear variable assignments
+  unsigned long arg0 = ctx->args[0];
+  bpf_printk("args[0]: %u", arg0);
+
+  unsigned long arg1 = ctx->args[1];
+  bpf_printk("args[1]: %u", arg1);
+
+  // Remove the duplicate access to args[1]
+
+  unsigned long arg2 = ctx->args[2];
+  bpf_printk("args[3]: %u", arg2);
+  bpf_printk("args[4]: %u", ctx->args[2]);
+
+  return 0;
+}
+
+char LICENSE[] SEC("license") = "GPL";

tests/c-form/xdp_modify.bpf.c

@@ -0,0 +1,21 @@
+// xdp_rewrite.c
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <linux/if_ether.h>
+
+SEC("xdp")
+int xdp_rewrite_mac(struct xdp_md *ctx)
+{
+    void *data_end = (void *)(long)ctx->data_end;
+    void *data     = (void *)(long)ctx->data;
+
+    struct ethhdr *eth = data;
+    if ((void*)(eth + 1) > data_end)
+        return XDP_PASS;
+    __u8 new_src[ETH_ALEN] = {0x02,0x00,0x00,0x00,0x00,0x02};
+    for (int i = 0; i < ETH_ALEN; i++) eth->h_source[i] = new_src[i];
+
+    return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";

tests/failing_tests/vmlinux/struct_field_access.py

@@ -0,0 +1,28 @@
+import logging
+
+from pythonbpf import bpf, section, bpfglobal, compile_to_ir
+from pythonbpf import compile  # noqa: F401
+from vmlinux import TASK_COMM_LEN  # noqa: F401
+from vmlinux import struct_trace_event_raw_sys_enter  # noqa: F401
+from ctypes import c_int64
+
+# from vmlinux import struct_uinput_device
+# from vmlinux import struct_blk_integrity_iter
+
+
+@bpf
+@section("tracepoint/syscalls/sys_enter_execve")
+def hello_world(ctx: struct_trace_event_raw_sys_enter) -> c_int64:
+    a = 2 + TASK_COMM_LEN + TASK_COMM_LEN
+    print(f"Hello, World{TASK_COMM_LEN} and {a}")
+    return c_int64(TASK_COMM_LEN + 2)
+
+
+@bpf
+@bpfglobal
+def LICENSE() -> str:
+    return "GPL"
+
+
+compile_to_ir("struct_field_access.py", "struct_field_access.ll", loglevel=logging.INFO)
+# compile()

tests/passing_tests/vmlinux/simple_struct_test.py

@@ -0,0 +1,47 @@
+import logging
+
+from pythonbpf import bpf, section, bpfglobal, compile_to_ir, map
+from pythonbpf import compile  # noqa: F401
+from vmlinux import TASK_COMM_LEN  # noqa: F401
+from vmlinux import struct_trace_event_raw_sys_enter  # noqa: F401
+from ctypes import c_uint64, c_int32, c_int64
+from pythonbpf.maps import HashMap
+
+# from vmlinux import struct_uinput_device
+# from vmlinux import struct_blk_integrity_iter
+
+
+@bpf
+@map
+def mymap() -> HashMap:
+    return HashMap(key=c_int32, value=c_uint64, max_entries=TASK_COMM_LEN)
+
+
+@bpf
+@map
+def mymap2() -> HashMap:
+    return HashMap(key=c_int32, value=c_uint64, max_entries=18)
+
+
+# Instructions to how to run this program
+# 1. Install PythonBPF: pip install pythonbpf
+# 2. Run the program: python examples/simple_struct_test.py
+# 3. Run the program with sudo: sudo tools/check.sh run examples/simple_struct_test.o
+# 4. Attach object file to any network device with something like ./check.sh run examples/simple_struct_test.o tailscale0
+# 5. send traffic through the device and observe effects
+@bpf
+@section("tracepoint/syscalls/sys_enter_execve")
+def hello_world(ctx: struct_trace_event_raw_sys_enter) -> c_int64:
+    a = 2 + TASK_COMM_LEN + TASK_COMM_LEN
+    print(f"Hello, World{TASK_COMM_LEN} and {a}")
+    return c_int64(TASK_COMM_LEN + 2)
+
+
+@bpf
+@bpfglobal
+def LICENSE() -> str:
+    return "GPL"
+
+
+compile_to_ir("simple_struct_test.py", "simple_struct_test.ll", loglevel=logging.DEBUG)
+# compile()