^^&&^^

Edit File: sysc_recv.stp

# recv _______________________________________________________
#
# long sys_recv(int fd, void __user *ubuf, size_t size, unsigned flags)
#
# On some kernels, the recv() syscall goes through
# sys_socketcall(), which then calls an inlined version of
# sys_recv(). So, we need to probe sys_socketcall() also.
#

@define _SYSCALL_RECV_NAME
%(
	name = "recv"
%)

@define _SYSCALL_RECV_ARGSTR
%(
	argstr = sprintf("%d, %p, %u, %s", s, buf_uaddr, len, flags_str)
%)

@define _SYSCALL_RECV_REGARGS
%(
	s = int_arg(1)
	buf_uaddr = pointer_arg(2)
	len = ulong_arg(3)
	flags = uint_arg(4)
%)

@define _SYSCALL_SOCKETCALL_RECV_REGARGS
%(
	__args = &@ulong_cast(pointer_arg(2))
	s = __int32(user_ulong(&@ulong_cast(__args)[0]))
	buf_uaddr = user_ulong(&@ulong_cast(__args)[1])
	len = user_ulong(&@ulong_cast(__args)[2])
	flags = __uint32(user_ulong(&@ulong_cast(__args)[3]))
%)

@define _SYSCALL_COMPAT_SOCKETCALL_RECV_REGARGS
%(
	__args = &@uint_cast(pointer_arg(2))
	s = user_int(&@uint_cast(__args)[0])
	buf_uaddr = user_uint32(&@uint_cast(__args)[1])
	len = user_uint32(&@uint_cast(__args)[2])
	flags = user_uint32(&@uint_cast(__args)[3])
%)

probe syscall.recv = dw_syscall.recv !, nd_syscall.recv ? {}
probe syscall.recv.return = dw_syscall.recv.return !, nd_syscall.recv.return ? {}

# dw_recv _____________________________________________________

probe dw_syscall.recv = __syscall.socketcall.recv ?,
	__syscall.compat_socketcall.recv ?,
	__syscall.recv ?
{
	@_SYSCALL_RECV_NAME
	flags_str = _msg_flags_str(flags)
	@_SYSCALL_RECV_ARGSTR
}
probe __syscall.socketcall.recv = kernel.function("sys_socketcall").call ?
{
	if (__int32($call) != @const("SYS_RECV")) next;
	s = __int32(user_ulong(&@ulong_cast($args)[0]))
	buf_uaddr = user_ulong(&@ulong_cast($args)[1])
	len = user_ulong(&@ulong_cast($args)[2])
	flags = __uint32(user_ulong(&@ulong_cast($args)[3]))
}
probe __syscall.compat_socketcall.recv =
	kernel.function("compat_sys_socketcall").call ?
{
	if (__int32($call) != @const("SYS_RECV")) next;
	s = user_int(&@uint_cast($args)[0])
	buf_uaddr = user_uint32(&@uint_cast($args)[1])
	len = user_uint32(&@uint_cast($args)[2])
	flags = user_uint32(&@uint_cast($args)[3])
}
probe __syscall.recv = kernel.function("sys_recv").call ?
{
	@__syscall_gate(@const("__NR_recv"))
	s = __int32($fd)
	buf_uaddr = $ubuf
	len = __ulong($size)
	flags = __uint32($flags)
}
probe dw_syscall.recv.return = __syscall.socketcall.recv.return ?,
	__syscall.recv.return ?
{
	@_SYSCALL_RECV_NAME
	@SYSC_RETVALSTR($return)
}
probe __syscall.socketcall.recv.return =
	kernel.function("sys_socketcall").return ?,
	kernel.function("compat_sys_socketcall").return ?
{
	if (__int32(@entry($call)) != @const("SYS_RECV")) next;
}
probe __syscall.recv.return = kernel.function("sys_recv").return ?
{
	@__syscall_gate(@const("__NR_recv"))
}

# nd_recv _____________________________________________________

probe nd_syscall.recv = nd1_syscall.recv!, nd2_syscall.recv!, tp_syscall.recv
  { }

probe nd1_syscall.recv = __nd1_syscall.recv ?,
	__nd1_syscall.socketcall.recv ?,
	__nd1_syscall.compat_socketcall.recv ?
{
	@_SYSCALL_RECV_NAME
	flags_str = _msg_flags_str(flags)
	@_SYSCALL_RECV_ARGSTR
}
probe __nd1_syscall.recv = kprobe.function("sys_recv").call ?
{
	asmlinkage()
	@__syscall_gate(@const("__NR_recv"))
	@_SYSCALL_RECV_REGARGS
}
probe __nd1_syscall.socketcall.recv = kprobe.function("sys_socketcall").call ?
{
	asmlinkage()
	if (int_arg(1) != @const("SYS_RECV")) next;
	@_SYSCALL_SOCKETCALL_RECV_REGARGS
}
probe __nd1_syscall.compat_socketcall.recv =
	kprobe.function("compat_sys_socketcall").call ?
{
	asmlinkage()
	if (int_arg(1) != @const("SYS_RECV")) next;
	@_SYSCALL_COMPAT_SOCKETCALL_RECV_REGARGS
}

/* kernel 4.17+ */
probe nd2_syscall.recv = __nd2_syscall.recv ?,
	__nd2_syscall.socketcall.recv ?,
	__nd2_syscall.compat_socketcall.recv ?
{
	@_SYSCALL_RECV_NAME
	flags_str = _msg_flags_str(flags)
	@_SYSCALL_RECV_ARGSTR
}
probe __nd2_syscall.recv = kprobe.function(@arch_syscall_prefix "sys_recv") ?
{
	__set_syscall_pt_regs(pointer_arg(1))
	@_SYSCALL_RECV_REGARGS
}
probe __nd2_syscall.socketcall.recv = kprobe.function(@arch_syscall_prefix "sys_socketcall").call ?
{
	__set_syscall_pt_regs(pointer_arg(1))
	if (int_arg(1) != @const("SYS_RECV")) next;
	@_SYSCALL_SOCKETCALL_RECV_REGARGS
}
probe __nd2_syscall.compat_socketcall.recv =
	kprobe.function(@arch_syscall_prefix "compat_sys_socketcall").call ?
{
	__set_syscall_pt_regs(pointer_arg(1))
	if (int_arg(1) != @const("SYS_RECV")) next;
	@_SYSCALL_COMPAT_SOCKETCALL_RECV_REGARGS
}

/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.recv = __tp_syscall.recv ?,
	__tp_syscall.socketcall.recv ?
{
	@_SYSCALL_RECV_NAME
	flags_str = _msg_flags_str(flags)
	@_SYSCALL_RECV_ARGSTR
}
probe __tp_syscall.recv = kernel.trace("sys_enter")
{
	__set_syscall_pt_regs($regs)
	@__syscall_gate(@const("__NR_recv"))
	@_SYSCALL_RECV_REGARGS
}
probe __tp_syscall.socketcall.recv = kernel.trace("sys_enter")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_socketcall"), @const("__NR_compat_socketcall"))
	if (int_arg(1) != @const("SYS_RECV")) next;
	if (@__compat_task) {
		@_SYSCALL_COMPAT_SOCKETCALL_RECV_REGARGS
	}
	else {
		@_SYSCALL_SOCKETCALL_RECV_REGARGS
	}
}

probe nd_syscall.recv.return = nd1_syscall.recv.return!, nd2_syscall.recv.return!, tp_syscall.recv.return
  { }

probe nd1_syscall.recv.return =	__nd1_syscall.recv.return ?,
	__nd1_syscall.socketcall.recv.return ?
{
	@_SYSCALL_RECV_NAME
	@SYSC_RETVALSTR(returnval())
}
probe __nd1_syscall.recv.return = kprobe.function("sys_recv").return ?
{
	@__syscall_gate(@const("__NR_recv"))
}
probe __nd1_syscall.socketcall.recv.return =
	kprobe.function("sys_socketcall").return ?,
	kprobe.function("compat_sys_socketcall").return ?
{
	if (@entry(__asmlinkage_int_arg(1)) != @const("SYS_RECV")) next;
}

/* kernel 4.17+ */
probe nd2_syscall.recv.return =
	kprobe.function(@arch_syscall_prefix "sys_recv").return ?,
	__nd2_syscall.socketcall.recv.return ?
{
	@_SYSCALL_RECV_NAME
	@SYSC_RETVALSTR(returnval())
}
probe __nd2_syscall.socketcall.recv.return =
	kprobe.function(@arch_syscall_prefix "sys_socketcall").return ?,
	kprobe.function(@arch_syscall_prefix "compat_sys_socketcall").return ?
{
	__set_syscall_pt_regs(@entry(pointer_arg(1)))
	if (int_arg(1) != @const("SYS_RECV")) next;
}

/* kernel 3.5+, but undesirable because it affects all syscalls */
probe tp_syscall.recv.return = __tp_syscall.recv.return ?,
	__tp_syscall.socketcall.recv.return ?
{
	@_SYSCALL_RECV_NAME
	@SYSC_RETVALSTR($ret)
}
probe __tp_syscall.recv.return = kernel.trace("sys_exit")
{
	@__syscall_gate(@const("__NR_recv"))
}
probe __tp_syscall.socketcall.recv.return = kernel.trace("sys_exit")
{
	__set_syscall_pt_regs($regs)
	@__syscall_compat_gate(@const("__NR_socketcall"), @const("__NR_compat_socketcall"))
	if (int_arg(1) != @const("SYS_RECV")) next;
}