Refactor: refactor find process (#2781)

component/process/process_freebsd.go

@@ -0,0 +1,217 @@
+package process
+
+import (
+	"encoding/binary"
+	"fmt"
+	"net/netip"
+	"strconv"
+	"strings"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+type Xinpgen12 [64]byte // size 64
+
+type InEndpoints12 struct {
+	FPort  [2]byte
+	LPort  [2]byte
+	FAddr  [16]byte
+	LAddr  [16]byte
+	ZoneID uint32
+} // size 40
+
+type XTcpcb12 struct {
+	Len         uint32        // offset 0
+	Padding1    [20]byte      // offset 4
+	SocketAddr  uint64        // offset 24
+	Padding2    [84]byte      // offset 32
+	Family      uint32        // offset 116
+	Padding3    [140]byte     // offset 120
+	InEndpoints InEndpoints12 // offset 260
+	Padding4    [444]byte     // offset 300
+} // size 744
+
+type XInpcb12 struct {
+	Len         uint32        // offset 0
+	Padding1    [12]byte      // offset 4
+	SocketAddr  uint64        // offset 16
+	Padding2    [84]byte      // offset 24
+	Family      uint32        // offset 108
+	Padding3    [140]byte     // offset 112
+	InEndpoints InEndpoints12 // offset 252
+	Padding4    [108]byte     // offset 292
+} // size 400
+
+type XFile12 struct {
+	Size     uint64   // offset 0
+	Pid      uint32   // offset 8
+	Padding1 [44]byte // offset 12
+	DataAddr uint64   // offset 56
+	Padding2 [64]byte // offset 64
+} // size 128
+
+var majorVersion = func() int {
+	releaseVersion, err := unix.Sysctl("kern.osrelease")
+	if err != nil {
+		return 0
+	}
+
+	majorVersionText, _, _ := strings.Cut(releaseVersion, ".")
+
+	majorVersion, err := strconv.Atoi(majorVersionText)
+	if err != nil {
+		return 0
+	}
+
+	return majorVersion
+}()
+
+func findProcessPath(network string, from netip.AddrPort, to netip.AddrPort) (string, error) {
+	switch majorVersion {
+	case 12, 13:
+		return findProcessPath12(network, from, to)
+	}
+
+	return "", ErrPlatformNotSupport
+}
+
+func findProcessPath12(network string, from netip.AddrPort, to netip.AddrPort) (string, error) {
+	switch network {
+	case TCP:
+		data, err := unix.SysctlRaw("net.inet.tcp.pcblist")
+		if err != nil {
+			return "", err
+		}
+
+		if len(data) < int(unsafe.Sizeof(Xinpgen12{})) {
+			return "", fmt.Errorf("invalid sysctl data len: %d", len(data))
+		}
+
+		data = data[unsafe.Sizeof(Xinpgen12{}):]
+
+		for len(data) > int(unsafe.Sizeof(XTcpcb12{}.Len)) {
+			tcb := (*XTcpcb12)(unsafe.Pointer(&data[0]))
+			if tcb.Len < uint32(unsafe.Sizeof(XTcpcb12{})) || uint32(len(data)) < tcb.Len {
+				break
+			}
+
+			data = data[tcb.Len:]
+
+			var (
+				connFromAddr netip.Addr
+				connToAddr   netip.Addr
+			)
+			if tcb.Family == unix.AF_INET {
+				connFromAddr = netip.AddrFrom4([4]byte(tcb.InEndpoints.LAddr[12:16]))
+				connToAddr = netip.AddrFrom4([4]byte(tcb.InEndpoints.FAddr[12:16]))
+			} else if tcb.Family == unix.AF_INET6 {
+				connFromAddr = netip.AddrFrom16(tcb.InEndpoints.LAddr)
+				connToAddr = netip.AddrFrom16(tcb.InEndpoints.FAddr)
+			} else {
+				continue
+			}
+
+			connFrom := netip.AddrPortFrom(connFromAddr, binary.BigEndian.Uint16(tcb.InEndpoints.LPort[:]))
+			connTo := netip.AddrPortFrom(connToAddr, binary.BigEndian.Uint16(tcb.InEndpoints.FPort[:]))
+
+			if connFrom == from && connTo == to {
+				pid, err := findPidBySocketAddr12(tcb.SocketAddr)
+				if err != nil {
+					return "", err
+				}
+
+				return findExecutableByPid(pid)
+			}
+		}
+	case UDP:
+		data, err := unix.SysctlRaw("net.inet.udp.pcblist")
+		if err != nil {
+			return "", err
+		}
+
+		if len(data) < int(unsafe.Sizeof(Xinpgen12{})) {
+			return "", fmt.Errorf("invalid sysctl data len: %d", len(data))
+		}
+
+		data = data[unsafe.Sizeof(Xinpgen12{}):]
+
+		for len(data) > int(unsafe.Sizeof(XInpcb12{}.Len)) {
+			icb := (*XInpcb12)(unsafe.Pointer(&data[0]))
+			if icb.Len < uint32(unsafe.Sizeof(XInpcb12{})) || uint32(len(data)) < icb.Len {
+				break
+			}
+			data = data[icb.Len:]
+
+			var connFromAddr netip.Addr
+
+			if icb.Family == unix.AF_INET {
+				connFromAddr = netip.AddrFrom4([4]byte(icb.InEndpoints.LAddr[12:16]))
+			} else if icb.Family == unix.AF_INET6 {
+				connFromAddr = netip.AddrFrom16(icb.InEndpoints.LAddr)
+			} else {
+				continue
+			}
+
+			connFrom := netip.AddrPortFrom(connFromAddr, binary.BigEndian.Uint16(icb.InEndpoints.LPort[:]))
+
+			if connFrom == from {
+				pid, err := findPidBySocketAddr12(icb.SocketAddr)
+				if err != nil {
+					return "", err
+				}
+
+				return findExecutableByPid(pid)
+			}
+		}
+	}
+
+	return "", ErrNotFound
+}
+
+func findPidBySocketAddr12(socketAddr uint64) (uint32, error) {
+	buf, err := unix.SysctlRaw("kern.file")
+	if err != nil {
+		return 0, err
+	}
+
+	filesLen := len(buf) / int(unsafe.Sizeof(XFile12{}))
+	files := unsafe.Slice((*XFile12)(unsafe.Pointer(&buf[0])), filesLen)
+
+	for _, file := range files {
+		if file.Size != uint64(unsafe.Sizeof(XFile12{})) {
+			return 0, fmt.Errorf("invalid xfile size: %d", file.Size)
+		}
+
+		if file.DataAddr == socketAddr {
+			return file.Pid, nil
+		}
+	}
+
+	return 0, ErrNotFound
+}
+
+func findExecutableByPid(pid uint32) (string, error) {
+	buf := make([]byte, unix.PathMax)
+	size := uint64(len(buf))
+	mib := [4]uint32{
+		unix.CTL_KERN,
+		14, // KERN_PROC
+		12, // KERN_PROC_PATHNAME
+		pid,
+	}
+
+	_, _, errno := unix.Syscall6(
+		unix.SYS___SYSCTL,
+		uintptr(unsafe.Pointer(&mib[0])),
+		uintptr(len(mib)),
+		uintptr(unsafe.Pointer(&buf[0])),
+		uintptr(unsafe.Pointer(&size)),
+		0,
+		0)
+	if errno != 0 || size == 0 {
+		return "", fmt.Errorf("sysctl: get proc name: %w", errno)
+	}
+
+	return string(buf[:size-1]), nil
+}