summaryrefslogtreecommitdiff
path: root/pkg/specgen/generate/security.go
blob: 7c818cf62f8d412cf434159044ea82b411504294 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
package generate

import (
	"strings"

	"github.com/containers/common/pkg/apparmor"
	"github.com/containers/common/pkg/capabilities"
	"github.com/containers/common/pkg/config"
	"github.com/containers/podman/v2/libpod"
	"github.com/containers/podman/v2/libpod/define"
	"github.com/containers/podman/v2/libpod/image"
	"github.com/containers/podman/v2/pkg/specgen"
	"github.com/containers/podman/v2/pkg/util"
	"github.com/opencontainers/runtime-tools/generate"
	"github.com/opencontainers/selinux/go-selinux/label"
	"github.com/pkg/errors"
	"github.com/sirupsen/logrus"
)

// setLabelOpts sets the label options of the SecurityConfig according to the
// input.
func setLabelOpts(s *specgen.SpecGenerator, runtime *libpod.Runtime, pidConfig specgen.Namespace, ipcConfig specgen.Namespace) error {
	if !runtime.EnableLabeling() || s.Privileged {
		s.SelinuxOpts = label.DisableSecOpt()
		return nil
	}

	var labelOpts []string
	if pidConfig.IsHost() {
		labelOpts = append(labelOpts, label.DisableSecOpt()...)
	} else if pidConfig.IsContainer() {
		ctr, err := runtime.LookupContainer(pidConfig.Value)
		if err != nil {
			return errors.Wrapf(err, "container %q not found", pidConfig.Value)
		}
		secopts, err := label.DupSecOpt(ctr.ProcessLabel())
		if err != nil {
			return errors.Wrapf(err, "failed to duplicate label %q ", ctr.ProcessLabel())
		}
		labelOpts = append(labelOpts, secopts...)
	}

	if ipcConfig.IsHost() {
		labelOpts = append(labelOpts, label.DisableSecOpt()...)
	} else if ipcConfig.IsContainer() {
		ctr, err := runtime.LookupContainer(ipcConfig.Value)
		if err != nil {
			return errors.Wrapf(err, "container %q not found", ipcConfig.Value)
		}
		secopts, err := label.DupSecOpt(ctr.ProcessLabel())
		if err != nil {
			return errors.Wrapf(err, "failed to duplicate label %q ", ctr.ProcessLabel())
		}
		labelOpts = append(labelOpts, secopts...)
	}

	s.SelinuxOpts = append(s.SelinuxOpts, labelOpts...)
	return nil
}

func setupApparmor(s *specgen.SpecGenerator, rtc *config.Config, g *generate.Generator) error {
	hasProfile := len(s.ApparmorProfile) > 0
	if !apparmor.IsEnabled() {
		if hasProfile && s.ApparmorProfile != "unconfined" {
			return errors.Errorf("Apparmor profile %q specified, but Apparmor is not enabled on this system", s.ApparmorProfile)
		}
		return nil
	}
	// If privileged and caller did not specify apparmor profiles return
	if s.Privileged && !hasProfile {
		return nil
	}
	if !hasProfile {
		s.ApparmorProfile = rtc.Containers.ApparmorProfile
	}
	if len(s.ApparmorProfile) > 0 {
		g.SetProcessApparmorProfile(s.ApparmorProfile)
	}

	return nil
}

func securityConfigureGenerator(s *specgen.SpecGenerator, g *generate.Generator, newImage *image.Image, rtc *config.Config) error {
	var (
		caplist []string
		err     error
	)
	// HANDLE CAPABILITIES
	// NOTE: Must happen before SECCOMP
	if s.Privileged {
		g.SetupPrivileged(true)
		caplist = capabilities.AllCapabilities()
	} else {
		caplist, err = capabilities.MergeCapabilities(rtc.Containers.DefaultCapabilities, s.CapAdd, s.CapDrop)
		if err != nil {
			return err
		}

		privCapsRequired := []string{}

		// If the container image specifies an label with a
		// capabilities.ContainerImageLabel then split the comma separated list
		// of capabilities and record them.  This list indicates the only
		// capabilities, required to run the container.
		var capsRequiredRequested []string
		for key, val := range s.Labels {
			if util.StringInSlice(key, capabilities.ContainerImageLabels) {
				capsRequiredRequested = strings.Split(val, ",")
			}
		}
		if !s.Privileged && len(capsRequiredRequested) > 0 {

			// Pass capRequiredRequested in CapAdd field to normalize capabilities names
			capsRequired, err := capabilities.MergeCapabilities(nil, capsRequiredRequested, nil)
			if err != nil {
				return errors.Wrapf(err, "capabilities requested by user or image are not valid: %q", strings.Join(capsRequired, ","))
			} else {
				// Verify all capRequiered are in the capList
				for _, cap := range capsRequired {
					if !util.StringInSlice(cap, caplist) {
						privCapsRequired = append(privCapsRequired, cap)
					}
				}
			}
			if len(privCapsRequired) == 0 {
				caplist = capsRequired
			} else {
				logrus.Errorf("capabilities requested by user or image are not allowed by default: %q", strings.Join(privCapsRequired, ","))
			}
		}
	}

	configSpec := g.Config
	configSpec.Process.Capabilities.Bounding = caplist

	if s.User == "" || s.User == "root" || s.User == "0" {
		configSpec.Process.Capabilities.Effective = caplist
		configSpec.Process.Capabilities.Permitted = caplist
		configSpec.Process.Capabilities.Inheritable = caplist
	} else {
		userCaps, err := capabilities.NormalizeCapabilities(s.CapAdd)
		if err != nil {
			return errors.Wrapf(err, "capabilities requested by user are not valid: %q", strings.Join(s.CapAdd, ","))
		}
		configSpec.Process.Capabilities.Effective = userCaps
		configSpec.Process.Capabilities.Permitted = userCaps
	}

	g.SetProcessNoNewPrivileges(s.NoNewPrivileges)

	if err := setupApparmor(s, rtc, g); err != nil {
		return err
	}

	// HANDLE SECCOMP
	if s.SeccompProfilePath != "unconfined" {
		seccompConfig, err := getSeccompConfig(s, configSpec, newImage)
		if err != nil {
			return err
		}
		configSpec.Linux.Seccomp = seccompConfig
	}

	// Clear default Seccomp profile from Generator for unconfined containers
	// and privileged containers which do not specify a seccomp profile.
	if s.SeccompProfilePath == "unconfined" || (s.Privileged && (s.SeccompProfilePath == config.SeccompOverridePath || s.SeccompProfilePath == config.SeccompDefaultPath)) {
		configSpec.Linux.Seccomp = nil
	}

	g.SetRootReadonly(s.ReadOnlyFilesystem)

	// Add default sysctls
	defaultSysctls, err := util.ValidateSysctls(rtc.Sysctls())
	if err != nil {
		return err
	}
	for sysctlKey, sysctlVal := range defaultSysctls {

		// Ignore mqueue sysctls if --ipc=host
		if s.IpcNS.IsHost() && strings.HasPrefix(sysctlKey, "fs.mqueue.") {
			logrus.Infof("Sysctl %s=%s ignored in containers.conf, since IPC Namespace set to host", sysctlKey, sysctlVal)

			continue
		}

		// Ignore net sysctls if --net=host
		if s.NetNS.IsHost() && strings.HasPrefix(sysctlKey, "net.") {
			logrus.Infof("Sysctl %s=%s ignored in containers.conf, since Network Namespace set to host", sysctlKey, sysctlVal)
			continue
		}

		// Ignore uts sysctls if --uts=host
		if s.UtsNS.IsHost() && (strings.HasPrefix(sysctlKey, "kernel.domainname") || strings.HasPrefix(sysctlKey, "kernel.hostname")) {
			logrus.Infof("Sysctl %s=%s ignored in containers.conf, since UTS Namespace set to host", sysctlKey, sysctlVal)
			continue
		}

		g.AddLinuxSysctl(sysctlKey, sysctlVal)
	}

	for sysctlKey, sysctlVal := range s.Sysctl {

		if s.IpcNS.IsHost() && strings.HasPrefix(sysctlKey, "fs.mqueue.") {
			return errors.Wrapf(define.ErrInvalidArg, "sysctl %s=%s can't be set since IPC Namespace set to host", sysctlKey, sysctlVal)
		}

		// Ignore net sysctls if --net=host
		if s.NetNS.IsHost() && strings.HasPrefix(sysctlKey, "net.") {
			return errors.Wrapf(define.ErrInvalidArg, "sysctl %s=%s can't be set since Host Namespace set to host", sysctlKey, sysctlVal)
		}

		// Ignore uts sysctls if --uts=host
		if s.UtsNS.IsHost() && (strings.HasPrefix(sysctlKey, "kernel.domainname") || strings.HasPrefix(sysctlKey, "kernel.hostname")) {
			return errors.Wrapf(define.ErrInvalidArg, "sysctl %s=%s can't be set since UTS Namespace set to host", sysctlKey, sysctlVal)
		}

		g.AddLinuxSysctl(sysctlKey, sysctlVal)
	}

	return nil
}