feat: replace exec.Command with go-cmd module

This should fix reaper problem in Talos.

Signed-off-by: Artem Chernyshev <artem.0xD2@gmail.com>

blockdevice/encryption/luks/luks.go

@@ -7,14 +7,16 @@ package luks
 
 import (
 	"bytes"
+	"context"
 	"encoding/binary"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"os"
-	"os/exec"
 	"strings"
 	"time"
 
+	"github.com/talos-systems/go-cmd/pkg/cmd"
 	"golang.org/x/sys/unix"
 
 	"github.com/talos-systems/go-blockdevice/blockdevice/encryption"
@@ -225,23 +227,16 @@ func (l *LUKS) ReadKeyslots(deviceName string) (*encryption.Keyslots, error) {
 
 // runCommand executes cryptsetup with arguments.
 func (l *LUKS) runCommand(args []string, stdin []byte) error {
-	cmd := exec.Command("cryptsetup", args...)
-
-	var out bytes.Buffer
-
-	if stdin != nil {
-		cmd.Stdin = bytes.NewBuffer(stdin)
-	}
-
-	cmd.Stdout = &out
-	cmd.Stderr = &out
-
-	err := cmd.Run()
+	_, err := cmd.RunContext(cmd.WithStdin(
+		context.Background(),
+		bytes.NewBuffer(stdin)), "cryptsetup", args...)
 	if err != nil {
-		if e, ok := err.(*exec.ExitError); ok { //nolint:errorlint
-			switch e.ExitCode() {
+		var exitError *cmd.ExitError
+
+		if errors.As(err, &exitError) {
+			switch exitError.ExitCode {
 			case 1:
-				if strings.Contains(out.String(), "Keyslot open failed.\nNo usable keyslot is available.") {
+				if strings.Contains(string(exitError.Output), "Keyslot open failed.\nNo usable keyslot is available.") {
 					return encryption.ErrEncryptionKeyRejected
 				}
 			case 2:
@@ -251,9 +246,7 @@ func (l *LUKS) runCommand(args []string, stdin []byte) error {
 			}
 		}
 
-		if !strings.Contains(err.Error(), "no child processes") {
-			return fmt.Errorf("failed to call cryptsetup: %w, output: %s", err, out.String())
-		}
+		return fmt.Errorf("failed to call cryptsetup: %w", err)
 	}
 
 	return nil

go.mod

@@ -3,14 +3,10 @@ module github.com/talos-systems/go-blockdevice
 go 1.14
 
 require (
-	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/google/uuid v1.1.2
-	github.com/kr/text v0.2.0 // indirect
-	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
-	github.com/stretchr/testify v1.6.1
+	github.com/stretchr/testify v1.7.0
+	github.com/talos-systems/go-cmd v0.0.0-20210216164758-68eb0067e0f0
 	github.com/talos-systems/go-retry v0.1.1-0.20201113203059-8c63d290a688
 	golang.org/x/sys v0.0.0-20201130171929-760e229fe7c5
 	golang.org/x/text v0.3.4
-	gopkg.in/check.v1 v1.0.0-20200902074654-038fdea0a05b // indirect
-	gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 // indirect
 )

go.sum

@@ -1,3 +1,5 @@
+github.com/armon/circbuf v0.0.0-20190214190532-5111143e8da2 h1:7Ip0wMmLHLRJdrloDxZfhMm0xrLXZS8+COSu2bXmEQs=
+github.com/armon/circbuf v0.0.0-20190214190532-5111143e8da2/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -14,8 +16,10 @@ github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLA
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
-github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/talos-systems/go-cmd v0.0.0-20210216164758-68eb0067e0f0 h1:DI+BjK+fcrLBc70Fi50dZocQcaHosqsuWHrGHKp2NzE=
+github.com/talos-systems/go-cmd v0.0.0-20210216164758-68eb0067e0f0/go.mod h1:kf+rZzTEmlDiYQ6ulslvRONnKLQH8x83TowltGMhO+k=
 github.com/talos-systems/go-retry v0.1.1-0.20201113203059-8c63d290a688 h1:U5wFGj5LXt/r+qfy1nGftQxJvEbg/lVJuasHKtk3K7s=
 github.com/talos-systems/go-retry v0.1.1-0.20201113203059-8c63d290a688/go.mod h1:HiXQqyVStZ35uSY/MTLWVvQVmC3lIW2MS5VdDaMtoKM=
 golang.org/x/sys v0.0.0-20201130171929-760e229fe7c5 h1:dMDtAap8F/+vsyXblqK90iTzYJjNix5MsXDicSYol6w=