Check root permissions in commands that need it

Otherwise the error shown is not helpful (it fails too late with
confusing errors).

Signed-off-by: Dimitris Karakasilis <dimitris@karakasilis.me>

go.sum

@@ -360,6 +360,8 @@ github.com/jtolds/gls v4.20.0+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfV
 github.com/julienschmidt/httprouter v1.2.0/go.mod h1:SYymIcj16QtmaHHD7aYtjjsJG7VTCxuUUipMqKk8s4w=
 github.com/kairos-io/kairos-sdk v0.0.14 h1:yVKaay70cjmAUY6m4uLoV9UguBv3Dx3JxAh2faRlUZo=
 github.com/kairos-io/kairos-sdk v0.0.14/go.mod h1:+fhVoCEA2hD7OFTmhDmy4pP3uC9q84OYhDa7irkEVWQ=
+github.com/kairos-io/kairos-sdk v0.0.12 h1:+uibTjjsAh8klupXHWpWse2AKww6p8ROu8Ii28t3k48=
+github.com/kairos-io/kairos-sdk v0.0.12/go.mod h1:AK9poWisuhnzri04diXnTG8L7EkOSUArSeeDn2LYFU0=
 github.com/kbinani/screenshot v0.0.0-20210720154843-7d3a670d8329 h1:qq2nCpSrXrmvDGRxW0ruW9BVEV1CN2a9YDOExdt+U0o=
 github.com/kbinani/screenshot v0.0.0-20210720154843-7d3a670d8329/go.mod h1:2VPVQDR4wO7KXHwP+DAypEy67rXf+okUx2zjgpCxZw4=
 github.com/kendru/darwin/go/depgraph v0.0.0-20221105232959-877d6a81060c h1:eKb4PqwAMhlqwXw0W3atpKaYaPGlXE/Fwh+xpCEYaPk=

internal/agent/agent.go

@@ -1,11 +1,13 @@
 package agent
 
 import (
+	"errors"
 	"fmt"
-	v1 "github.com/kairos-io/kairos-agent/v2/pkg/types/v1"
 	"os"
 	"path/filepath"
 
+	v1 "github.com/kairos-io/kairos-agent/v2/pkg/types/v1"
+
 	hook "github.com/kairos-io/kairos-agent/v2/internal/agent/hooks"
 	"github.com/kairos-io/kairos-agent/v2/internal/bus"
 	config "github.com/kairos-io/kairos-agent/v2/pkg/config"
@@ -94,3 +96,11 @@ func Run(opts ...Option) error {
 	}
 	return err
 }
+
+func checkRoot() error {
+	if os.Geteuid() != 0 {
+		return errors.New("this command requires root privileges")
+	}
+
+	return nil
+}

internal/agent/install.go

@@ -5,8 +5,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	fsutils "github.com/kairos-io/kairos-agent/v2/pkg/utils/fs"
-	"github.com/sanity-io/litter"
 	"net/url"
 	"os"
 	"path/filepath"
@@ -14,6 +12,9 @@ import (
 	"syscall"
 	"time"
 
+	fsutils "github.com/kairos-io/kairos-agent/v2/pkg/utils/fs"
+	"github.com/sanity-io/litter"
+
 	hook "github.com/kairos-io/kairos-agent/v2/internal/agent/hooks"
 	"github.com/kairos-io/kairos-agent/v2/internal/bus"
 	"github.com/kairos-io/kairos-agent/v2/internal/cmd"
@@ -54,6 +55,10 @@ func displayInfo(agentConfig *Config) {
 }
 
 func ManualInstall(c, device string, reboot, poweroff, strictValidations bool) error {
+	if err := checkRoot(); err != nil {
+		return err
+	}
+
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
@@ -84,6 +89,10 @@ func ManualInstall(c, device string, reboot, poweroff, strictValidations bool) e
 }
 
 func Install(dir ...string) error {
+	if err := checkRoot(); err != nil {
+		return err
+	}
+
 	var cc *config.Config
 	var err error
 

internal/agent/interactive_install.go

@@ -130,6 +130,10 @@ func detectDevice() string {
 }
 
 func InteractiveInstall(debug, spawnShell bool) error {
+	if err := checkRoot(); err != nil {
+		return err
+	}
+
 	var sshUsers []string
 	bus.Manager.Initialize()
 

internal/agent/reset.go

@@ -3,6 +3,10 @@ package agent
 import (
 	"encoding/json"
 	"fmt"
+	"os"
+	"sync"
+	"time"
+
 	hook "github.com/kairos-io/kairos-agent/v2/internal/agent/hooks"
 	"github.com/kairos-io/kairos-agent/v2/internal/bus"
 	"github.com/kairos-io/kairos-agent/v2/internal/cmd"
@@ -12,16 +16,17 @@ import (
 	"github.com/kairos-io/kairos-sdk/collector"
 	"github.com/kairos-io/kairos-sdk/machine"
 	"github.com/kairos-io/kairos-sdk/utils"
-	"os"
-	"sync"
-	"time"
 
 	"github.com/mudler/go-pluggable"
 )
 
 func Reset(reboot, unattended bool, dir ...string) error {
+	if err := checkRoot(); err != nil {
+		return err
+	}
+
 	bus.Manager.Initialize()
-	
+
 	// This config is only for reset branding.
 	agentConfig, err := LoadConfig()
 	if err != nil {

internal/agent/upgrade.go

@@ -4,10 +4,12 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	hook "github.com/kairos-io/kairos-agent/v2/internal/agent/hooks"
-	"github.com/spf13/viper"
 	"sort"
 
+	"github.com/spf13/viper"
+
+	hook "github.com/kairos-io/kairos-agent/v2/internal/agent/hooks"
+
 	"github.com/Masterminds/semver/v3"
 	"github.com/kairos-io/kairos-agent/v2/internal/bus"
 	"github.com/kairos-io/kairos-agent/v2/pkg/action"
@@ -51,6 +53,10 @@ func ListReleases(includePrereleases bool) semver.Collection {
 
 func Upgrade(
 	version, source string, force, strictValidations bool, dirs []string, preReleases, upgradeRecovery bool) error {
+	if err := checkRoot(); err != nil {
+		return err
+	}
+
 	bus.Manager.Initialize()
 
 	if version == "" && source == "" {

main.go

@@ -4,13 +4,14 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"github.com/kairos-io/kairos-agent/v2/pkg/utils"
 	"os"
 	"path/filepath"
 	"regexp"
 	"runtime"
 	"strings"
 
+	"github.com/kairos-io/kairos-agent/v2/pkg/utils"
+
 	"github.com/kairos-io/kairos-agent/v2/internal/agent"
 	"github.com/kairos-io/kairos-agent/v2/internal/bus"
 	"github.com/kairos-io/kairos-agent/v2/internal/common"