An AfterFilter represents a socket system call filter after an execution of a system call.
It will only be executed after a system call for a socket that has an entry in internal table. If the filter returns a non-nil error, the system call function returns the non-nil error.
type AfterFilter func(*Status) error
A Cookie represents a 3-tuple of a socket; address family, socket type and protocol number.
type Cookie uint64
func (c Cookie) Family() int
Family returns an address family.
func (c Cookie) Protocol() int
Protocol returns a protocol number.
func (c Cookie) Type() int
Type returns a socket type.
A Filter represents a socket system call filter.
It will only be executed before a system call for a socket that has an entry in internal table. If the filter returns a non-nil error, the execution of system call will be canceled and the system call function returns the non-nil error. It can return a non-nil AfterFilter for filtering after the execution of the system call.
type Filter func(*Status) (AfterFilter, error)
A FilterType represents a filter type.
type FilterType int
const (
FilterSocket FilterType = iota // for Socket
FilterConnect // for Connect or ConnectEx
FilterListen // for Listen
FilterAccept // for Accept, Accept4 or AcceptEx
FilterGetsockoptInt // for GetsockoptInt
FilterClose // for Close or Closesocket
)
Sockets maps a socket descriptor to the status of socket.
type Sockets map[int]Status
A Stat represents a per-cookie socket statistics.
type Stat struct {
Family int // address family
Type int // socket type
Protocol int // protocol number
Opened uint64 // number of sockets opened
Connected uint64 // number of sockets connected
Listened uint64 // number of sockets listened
Accepted uint64 // number of sockets accepted
Closed uint64 // number of sockets closed
OpenFailed uint64 // number of sockets open failed
ConnectFailed uint64 // number of sockets connect failed
ListenFailed uint64 // number of sockets listen failed
AcceptFailed uint64 // number of sockets accept failed
CloseFailed uint64 // number of sockets close failed
}
func (st Stat) String() string
A Status represents the status of a socket.
type Status struct {
Cookie Cookie
Err error // error status of socket system call
SocketErr error // error status of socket by SO_ERROR
}
func (so Status) String() string
A Switch represents a callpath point switch for socket system calls.
type Switch struct {
// contains filtered or unexported fields
}
func (sw *Switch) Accept(s int) (ns int, sa syscall.Sockaddr, err error)
Accept wraps syscall.Accept.
func (sw *Switch) Accept4(s, flags int) (ns int, sa syscall.Sockaddr, err error)
Accept4 wraps syscall.Accept4.
func (sw *Switch) Close(s int) (err error)
Close wraps syscall.Close.
func (sw *Switch) Connect(s int, sa syscall.Sockaddr) (err error)
Connect wraps syscall.Connect.
func (sw *Switch) GetsockoptInt(s, level, opt int) (soerr int, err error)
GetsockoptInt wraps syscall.GetsockoptInt.
func (sw *Switch) Listen(s, backlog int) (err error)
Listen wraps syscall.Listen.
func (sw *Switch) Set(t FilterType, f Filter)
Set deploys the socket system call filter f for the filter type t.
func (sw *Switch) Socket(family, sotype, proto int) (s int, err error)
Socket wraps syscall.Socket.
func (sw *Switch) Sockets() Sockets
Sockets returns mappings of socket descriptor to socket status.
func (sw *Switch) Stats() []Stat
Stats returns a list of per-cookie socket statistics.