Merge pull request #17 from jean-edouard/ptrace

xattr: add cap_sys_ptrace to supported capabilities

Author: rmohr

.bazelversion

@@ -1 +1 @@
-3.1.0
+4.2.1

cmd/xattr.go

@@ -55,7 +55,7 @@ func NewXATTRCmd() *cobra.Command {
 			}
 			tarWriter := tar.NewWriter(streamOutput)
 			defer tarWriter.Close()
-			return xattr.Apply(tar.NewReader(streamInput), tarWriter , capabilityMap, labelMap)
+			return xattr.Apply(tar.NewReader(streamInput), tarWriter, capabilityMap, labelMap)
 		},
 	}
 

pkg/xattr/testdata/regenerate.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+
+TMPDIR=$(mktemp -d)
+trap 'rm -rf "${TMPDIR}"' EXIT
+
+touch ${TMPDIR}/selinux
+touch ${TMPDIR}/cap_net_bind_service
+touch ${TMPDIR}/cap_chown
+touch ${TMPDIR}/cap_sys_ptrace
+touch ${TMPDIR}/cap_all
+sudo chcon -t user_home_t ${TMPDIR}/selinux
+
+sudo setcap 'cap_net_bind_service=+ep' ${TMPDIR}/cap_net_bind_service
+sudo setcap 'cap_chown=+ep' ${TMPDIR}/cap_chown
+sudo setcap 'cap_sys_ptrace=+ep' ${TMPDIR}/cap_sys_ptrace
+sudo setcap 'cap_net_bind_service,cap_chown,cap_sys_ptrace=+ep' ${TMPDIR}/cap_all
+tar -C ${TMPDIR} --xattrs -cvf xattr.tar .

pkg/xattr/testdata/xattr.tar

@@ -13,7 +13,9 @@ const (
 
 var cap_empty_bitmask = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 var supported_capabilities = map[string][]byte{
+	"cap_chown":            {1, 0, 0, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
 	"cap_net_bind_service": {1, 0, 0, 2, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+	"cap_sys_ptrace":       {1, 0, 0, 2, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
 }
 
 func AddCapabilities(pax map[string]string, capabilities []string) error {
@@ -37,7 +39,7 @@ func SetSELinuxLabel(pax map[string]string, label string) error {
 	if label == "" {
 		return fmt.Errorf("label must not be empty, but got '%s'", label)
 	}
-	pax[selinux_header] = fmt.Sprintf("%s\x00",label)
+	pax[selinux_header] = fmt.Sprintf("%s\x00", label)
 	return nil
 }
 

pkg/xattr/xattr.go

@@ -14,7 +14,7 @@ var g *GomegaWithT
 
 func TestSettingSELinuxLabel(t *testing.T) {
 	g = NewGomegaWithT(t)
-	referenceEntry, err := getHeader("blub")
+	referenceEntry, err := getHeader("./selinux")
 	g.Expect(err).ToNot(HaveOccurred())
 
 	generatedEntry := &tar.Header{Name: "blub"}
@@ -43,3 +43,45 @@ func getHeader(name string) (*tar.Header, error) {
 	}
 	return nil, fmt.Errorf("entry %v does not exist", name)
 }
+
+func Test_Capabilities(t *testing.T) {
+	tests := []struct {
+		name         string
+		entry        string
+		capabilities []string
+	}{
+		{
+			name:         "should set cap_chown",
+			entry:        "./cap_chown",
+			capabilities: []string{"cap_chown"},
+		},
+		{
+			name:         "should set cap_net_bind_service",
+			entry:        "./cap_net_bind_service",
+			capabilities: []string{"cap_net_bind_service"},
+		},
+		{
+			name:         "should set cap_sys_ptrace",
+			entry:        "./cap_sys_ptrace",
+			capabilities: []string{"cap_sys_ptrace"},
+		},
+		{
+			name:         "should set all implemented capabilities",
+			entry:        "./cap_all",
+			capabilities: []string{"cap_chown", "cap_net_bind_service", "cap_sys_ptrace"},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			g = NewGomegaWithT(t)
+			referenceEntry, err := getHeader(tt.entry)
+			g.Expect(err).ToNot(HaveOccurred())
+
+			generatedEntry := &tar.Header{Name: "blub"}
+
+			g.Expect(enrichEntry(generatedEntry, map[string][]string{"blub": tt.capabilities}, nil)).To(Succeed())
+
+			g.Expect(generatedEntry.PAXRecords[capabilities_header]).To(Equal(referenceEntry.PAXRecords[capabilities_header]))
+		})
+	}
+}