github.com/ubuntu-core/snappy@v0.0.0-20210827154228-9e584df982bb/snapdtool/cmdutil_test.go (about)

     1  // -*- Mode: Go; indent-tabs-mode: t -*-
     2  
     3  /*
     4   * Copyright (C) 2016-2020 Canonical Ltd
     5   *
     6   * This program is free software: you can redistribute it and/or modify
     7   * it under the terms of the GNU General Public License version 3 as
     8   * published by the Free Software Foundation.
     9   *
    10   * This program is distributed in the hope that it will be useful,
    11   * but WITHOUT ANY WARRANTY; without even the implied warranty of
    12   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13   * GNU General Public License for more details.
    14   *
    15   * You should have received a copy of the GNU General Public License
    16   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    17   *
    18   */
    19  
    20  package snapdtool_test
    21  
    22  import (
    23  	"fmt"
    24  	"io/ioutil"
    25  	"os"
    26  	"os/exec"
    27  	"path/filepath"
    28  	"strings"
    29  
    30  	. "gopkg.in/check.v1"
    31  
    32  	"github.com/snapcore/snapd/dirs"
    33  	"github.com/snapcore/snapd/osutil"
    34  	"github.com/snapcore/snapd/snapdtool"
    35  )
    36  
    37  var truePath = osutil.LookPathDefault("true", "/bin/true")
    38  
    39  type cmdutilSuite struct{}
    40  
    41  var _ = Suite(&cmdutilSuite{})
    42  
    43  func (s *cmdutilSuite) SetUpTest(c *C) {
    44  	dirs.SetRootDir(c.MkDir())
    45  }
    46  
    47  func (s *cmdutilSuite) TearDownTest(c *C) {
    48  	dirs.SetRootDir("")
    49  }
    50  
    51  func (s *cmdutilSuite) makeMockLdSoConf(c *C, root string) {
    52  	ldSoConf := filepath.Join(root, "/etc/ld.so.conf")
    53  	ldSoConfD := ldSoConf + ".d"
    54  
    55  	err := os.MkdirAll(filepath.Dir(ldSoConf), 0755)
    56  	c.Assert(err, IsNil)
    57  	err = os.MkdirAll(ldSoConfD, 0755)
    58  	c.Assert(err, IsNil)
    59  
    60  	err = ioutil.WriteFile(ldSoConf, []byte("include /etc/ld.so.conf.d/*.conf"), 0644)
    61  	c.Assert(err, IsNil)
    62  
    63  	ldSoConf1 := filepath.Join(ldSoConfD, "x86_64-linux-gnu.conf")
    64  
    65  	err = ioutil.WriteFile(ldSoConf1, []byte(`
    66  # Multiarch support
    67  /lib/x86_64-linux-gnu
    68  /usr/lib/x86_64-linux-gnu`), 0644)
    69  	c.Assert(err, IsNil)
    70  }
    71  
    72  func (s *cmdutilSuite) TestCommandFromSystemSnap(c *C) {
    73  	for _, snap := range []string{"core", "snapd"} {
    74  
    75  		root := filepath.Join(dirs.SnapMountDir, snap, "current")
    76  		s.makeMockLdSoConf(c, root)
    77  
    78  		os.MkdirAll(filepath.Join(root, "/usr/bin"), 0755)
    79  		osutil.CopyFile(truePath, filepath.Join(root, "/usr/bin/xdelta3"), 0)
    80  		cmd, err := snapdtool.CommandFromSystemSnap("/usr/bin/xdelta3", "--some-xdelta-arg")
    81  		c.Assert(err, IsNil)
    82  
    83  		out, err := exec.Command("/bin/sh", "-c", fmt.Sprintf("readelf -l %s |grep interpreter:|cut -f2 -d:|cut -f1 -d]", truePath)).Output()
    84  		c.Assert(err, IsNil)
    85  		interp := strings.TrimSpace(string(out))
    86  
    87  		c.Check(cmd.Args, DeepEquals, []string{
    88  			filepath.Join(root, interp),
    89  			"--library-path",
    90  			fmt.Sprintf("%s/lib/x86_64-linux-gnu:%s/usr/lib/x86_64-linux-gnu", root, root),
    91  			filepath.Join(root, "/usr/bin/xdelta3"),
    92  			"--some-xdelta-arg",
    93  		})
    94  	}
    95  }
    96  
    97  func (s *cmdutilSuite) TestCommandFromCoreSymlinkCycle(c *C) {
    98  	root := filepath.Join(dirs.SnapMountDir, "/core/current")
    99  	s.makeMockLdSoConf(c, root)
   100  
   101  	os.MkdirAll(filepath.Join(root, "/usr/bin"), 0755)
   102  	osutil.CopyFile(truePath, filepath.Join(root, "/usr/bin/xdelta3"), 0)
   103  
   104  	out, err := exec.Command("/bin/sh", "-c", "readelf -l /bin/true |grep interpreter:|cut -f2 -d:|cut -f1 -d]").Output()
   105  	c.Assert(err, IsNil)
   106  	interp := strings.TrimSpace(string(out))
   107  
   108  	coreInterp := filepath.Join(root, interp)
   109  	c.Assert(os.MkdirAll(filepath.Dir(coreInterp), 0755), IsNil)
   110  	c.Assert(os.Symlink(filepath.Base(coreInterp), coreInterp), IsNil)
   111  
   112  	_, err = snapdtool.CommandFromSystemSnap("/usr/bin/xdelta3", "--some-xdelta-arg")
   113  	c.Assert(err, ErrorMatches, "cannot run command from core: symlink cycle found")
   114  }