github.com/alexis81/domosgo@v0.0.0-20191016125037-5aee90a434af/Domos/src/golang.org/x/sys/unix/creds_test.go (about)

     1  // Copyright 2012 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build linux
     6  
     7  package unix_test
     8  
     9  import (
    10  	"bytes"
    11  	"go/build"
    12  	"net"
    13  	"os"
    14  	"syscall"
    15  	"testing"
    16  
    17  	"golang.org/x/sys/unix"
    18  )
    19  
    20  // TestSCMCredentials tests the sending and receiving of credentials
    21  // (PID, UID, GID) in an ancillary message between two UNIX
    22  // sockets. The SO_PASSCRED socket option is enabled on the sending
    23  // socket for this to work.
    24  func TestSCMCredentials(t *testing.T) {
    25  	socketTypeTests := []struct {
    26  		socketType int
    27  		dataLen    int
    28  	}{
    29  		{
    30  			unix.SOCK_STREAM,
    31  			1,
    32  		}, {
    33  			unix.SOCK_DGRAM,
    34  			0,
    35  		},
    36  	}
    37  
    38  	for _, tt := range socketTypeTests {
    39  		if tt.socketType == unix.SOCK_DGRAM && !atLeast1p10() {
    40  			t.Log("skipping DGRAM test on pre-1.10")
    41  			continue
    42  		}
    43  
    44  		fds, err := unix.Socketpair(unix.AF_LOCAL, tt.socketType, 0)
    45  		if err != nil {
    46  			t.Fatalf("Socketpair: %v", err)
    47  		}
    48  		defer unix.Close(fds[0])
    49  		defer unix.Close(fds[1])
    50  
    51  		err = unix.SetsockoptInt(fds[0], unix.SOL_SOCKET, unix.SO_PASSCRED, 1)
    52  		if err != nil {
    53  			t.Fatalf("SetsockoptInt: %v", err)
    54  		}
    55  
    56  		srvFile := os.NewFile(uintptr(fds[0]), "server")
    57  		defer srvFile.Close()
    58  		srv, err := net.FileConn(srvFile)
    59  		if err != nil {
    60  			t.Errorf("FileConn: %v", err)
    61  			return
    62  		}
    63  		defer srv.Close()
    64  
    65  		cliFile := os.NewFile(uintptr(fds[1]), "client")
    66  		defer cliFile.Close()
    67  		cli, err := net.FileConn(cliFile)
    68  		if err != nil {
    69  			t.Errorf("FileConn: %v", err)
    70  			return
    71  		}
    72  		defer cli.Close()
    73  
    74  		var ucred unix.Ucred
    75  		if os.Getuid() != 0 {
    76  			ucred.Pid = int32(os.Getpid())
    77  			ucred.Uid = 0
    78  			ucred.Gid = 0
    79  			oob := unix.UnixCredentials(&ucred)
    80  			_, _, err := cli.(*net.UnixConn).WriteMsgUnix(nil, oob, nil)
    81  			if op, ok := err.(*net.OpError); ok {
    82  				err = op.Err
    83  			}
    84  			if sys, ok := err.(*os.SyscallError); ok {
    85  				err = sys.Err
    86  			}
    87  			if err != syscall.EPERM {
    88  				t.Fatalf("WriteMsgUnix failed with %v, want EPERM", err)
    89  			}
    90  		}
    91  
    92  		ucred.Pid = int32(os.Getpid())
    93  		ucred.Uid = uint32(os.Getuid())
    94  		ucred.Gid = uint32(os.Getgid())
    95  		oob := unix.UnixCredentials(&ucred)
    96  
    97  		// On SOCK_STREAM, this is internally going to send a dummy byte
    98  		n, oobn, err := cli.(*net.UnixConn).WriteMsgUnix(nil, oob, nil)
    99  		if err != nil {
   100  			t.Fatalf("WriteMsgUnix: %v", err)
   101  		}
   102  		if n != 0 {
   103  			t.Fatalf("WriteMsgUnix n = %d, want 0", n)
   104  		}
   105  		if oobn != len(oob) {
   106  			t.Fatalf("WriteMsgUnix oobn = %d, want %d", oobn, len(oob))
   107  		}
   108  
   109  		oob2 := make([]byte, 10*len(oob))
   110  		n, oobn2, flags, _, err := srv.(*net.UnixConn).ReadMsgUnix(nil, oob2)
   111  		if err != nil {
   112  			t.Fatalf("ReadMsgUnix: %v", err)
   113  		}
   114  		if flags != 0 {
   115  			t.Fatalf("ReadMsgUnix flags = 0x%x, want 0", flags)
   116  		}
   117  		if n != tt.dataLen {
   118  			t.Fatalf("ReadMsgUnix n = %d, want %d", n, tt.dataLen)
   119  		}
   120  		if oobn2 != oobn {
   121  			// without SO_PASSCRED set on the socket, ReadMsgUnix will
   122  			// return zero oob bytes
   123  			t.Fatalf("ReadMsgUnix oobn = %d, want %d", oobn2, oobn)
   124  		}
   125  		oob2 = oob2[:oobn2]
   126  		if !bytes.Equal(oob, oob2) {
   127  			t.Fatal("ReadMsgUnix oob bytes don't match")
   128  		}
   129  
   130  		scm, err := unix.ParseSocketControlMessage(oob2)
   131  		if err != nil {
   132  			t.Fatalf("ParseSocketControlMessage: %v", err)
   133  		}
   134  		newUcred, err := unix.ParseUnixCredentials(&scm[0])
   135  		if err != nil {
   136  			t.Fatalf("ParseUnixCredentials: %v", err)
   137  		}
   138  		if *newUcred != ucred {
   139  			t.Fatalf("ParseUnixCredentials = %+v, want %+v", newUcred, ucred)
   140  		}
   141  	}
   142  }
   143  
   144  // atLeast1p10 reports whether we are running on Go 1.10 or later.
   145  func atLeast1p10() bool {
   146  	for _, ver := range build.Default.ReleaseTags {
   147  		if ver == "go1.10" {
   148  			return true
   149  		}
   150  	}
   151  	return false
   152  }