Add ktime

This commit is contained in:
Pragyansh Chaturvedi
2025-09-09 23:40:05 +05:30
parent 8ee5d03c5d
commit 3628276e08
5 changed files with 28 additions and 6 deletions

View File

@ -33,7 +33,7 @@ long hello_again(void *ctx) {
u64 delta = bpf_ktime_get_ns() - *tsp;
if (delta < 1000000000) {
// output if time is less than 1 second
bpf_trace_printk("%d\\n", delta / 1000000);
bpf_printk("execve called within last second");
}
bpf_map_delete_elem(&last, &key);
}

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@ -1,6 +1,6 @@
from pythonbpf.decorators import bpf, map, section, bpfglobal
from ctypes import c_void_p, c_int64, c_int32, c_uint64
from pythonbpf.helpers import bpf_ktime_get_ns
from pythonbpf.helpers import ktime
from pythonbpf.maps import HashMap
@ -9,6 +9,7 @@ from pythonbpf.maps import HashMap
def last() -> HashMap:
return HashMap(key_type=c_uint64, value_type=c_uint64, max_entries=1)
@bpf
@section("tracepoint/syscalls/sys_enter_execve")
def hello(ctx: c_void_p) -> c_int32:
@ -24,9 +25,10 @@ def hello_again(ctx: c_void_p) -> c_int64:
key = 0
tsp = last().lookup(key)
print(tsp)
ts = bpf_ktime_get_ns()
ktime()
return c_int64(0)
@bpf
@bpfglobal
def LICENSE() -> str:

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@ -3,7 +3,15 @@ from llvmlite import ir
def bpf_ktime_get_ns_emitter(call, module, builder, func):
pass
"""
Emit LLVM IR for bpf_ktime_get_ns helper function call.
"""
helper_id = ir.Constant(ir.IntType(64), 5)
fn_type = ir.FunctionType(ir.IntType(64), [], var_arg=False)
fn_ptr_type = ir.PointerType(fn_type)
fn_ptr = builder.inttoptr(helper_id, fn_ptr_type)
result = builder.call(fn_ptr, [], tail=False)
return result
def bpf_map_lookup_elem_emitter(map_ptr, key_ptr, module, builder):
@ -62,3 +70,14 @@ def bpf_printk_emitter(call, module, builder, func):
builder.call(fn_ptr, [fmt_ptr, ir.Constant(
ir.IntType(32), len(fmt_str))], tail=True)
helper_func_list = {
"lookup": bpf_map_lookup_elem_emitter,
"print": bpf_printk_emitter,
"ktime": bpf_ktime_get_ns_emitter,
}
def handle_helper_call(call, module, builder, func):
return None

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@ -123,7 +123,7 @@ def process_func_body(module, builder, func_node, func, ret_type, map_sym_tab):
call = stmt.value
if isinstance(call.func, ast.Name) and call.func.id == "print":
bpf_printk_emitter(call, module, builder, func)
if isinstance(call.func, ast.Name) and call.func.id == "bpf_ktime_get_ns":
if isinstance(call.func, ast.Name) and call.func.id == "ktime":
bpf_ktime_get_ns_emitter(call, module, builder, func)
elif isinstance(stmt, ast.Assign):
handle_assign(module, builder, stmt, map_sym_tab, local_sym_tab)

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@ -1,4 +1,5 @@
import ctypes
def bpf_ktime_get_ns():
def ktime():
return ctypes.c_int64(0)