podman/pkg/domain/utils/scp.go

451 lines
15 KiB
Go

package utils
import (
"fmt"
"net/url"
"os"
"os/exec"
"os/user"
"strconv"
"strings"
"github.com/containers/common/pkg/config"
"github.com/containers/common/pkg/ssh"
"github.com/containers/image/v5/transports/alltransports"
"github.com/containers/podman/v4/libpod/define"
"github.com/containers/podman/v4/pkg/domain/entities"
"github.com/sirupsen/logrus"
)
func ExecuteTransfer(src, dst string, parentFlags []string, quiet bool, sshMode ssh.EngineMode) (*entities.ImageLoadReport, *entities.ImageScpOptions, *entities.ImageScpOptions, []string, error) {
source := entities.ImageScpOptions{}
dest := entities.ImageScpOptions{}
sshInfo := entities.ImageScpConnections{}
report := entities.ImageLoadReport{Names: []string{}}
podman, err := os.Executable()
if err != nil {
return nil, nil, nil, nil, err
}
f, err := os.CreateTemp("", "podman") // open temp file for load/save output
if err != nil {
return nil, nil, nil, nil, err
}
locations := []*entities.ImageScpOptions{}
cliConnections := []string{}
args := []string{src}
if len(dst) > 0 {
args = append(args, dst)
}
for _, arg := range args {
loc, connect, err := ParseImageSCPArg(arg)
if err != nil {
return nil, nil, nil, nil, err
}
locations = append(locations, loc)
cliConnections = append(cliConnections, connect...)
}
source = *locations[0]
switch {
case len(locations) > 1:
if err = ValidateSCPArgs(locations); err != nil {
return nil, nil, nil, nil, err
}
dest = *locations[1]
case len(locations) == 1:
switch {
case len(locations[0].Image) == 0:
return nil, nil, nil, nil, fmt.Errorf("no source image specified: %w", define.ErrInvalidArg)
case len(locations[0].Image) > 0 && !locations[0].Remote && len(locations[0].User) == 0: // if we have podman image scp $IMAGE
return nil, nil, nil, nil, fmt.Errorf("must specify a destination: %w", define.ErrInvalidArg)
}
}
source.Quiet = quiet
source.File = f.Name() // after parsing the arguments, set the file for the save/load
dest.File = source.File
defer os.Remove(source.File)
allLocal := true // if we are all localhost, do not validate connections but if we are using one localhost and one non we need to use sshd
for _, val := range cliConnections {
if !strings.Contains(val, "@localhost::") {
allLocal = false
break
}
}
if allLocal {
cliConnections = []string{}
}
cfg, err := config.Default()
if err != nil {
return nil, nil, nil, nil, err
}
err = GetServiceInformation(&sshInfo, cliConnections, cfg)
if err != nil {
return nil, nil, nil, nil, err
}
saveCmd, loadCmd := CreateCommands(source, dest, parentFlags, podman)
switch {
case source.Remote: // if we want to load FROM the remote, dest can either be local or remote in this case
err = SaveToRemote(source.Image, source.File, "", sshInfo.URI[0], sshInfo.Identities[0], sshMode)
if err != nil {
return nil, nil, nil, nil, err
}
if dest.Remote { // we want to load remote -> remote, both source and dest are remote
rep, id, err := LoadToRemote(dest, dest.File, "", sshInfo.URI[1], sshInfo.Identities[1], sshMode)
if err != nil {
return nil, nil, nil, nil, err
}
if len(rep) > 0 {
fmt.Println(rep)
}
if len(id) > 0 {
report.Names = append(report.Names, id)
}
break
}
id, err := ExecPodman(dest, podman, loadCmd)
if err != nil {
return nil, nil, nil, nil, err
}
if len(id) > 0 {
report.Names = append(report.Names, id)
}
case dest.Remote: // remote host load, implies source is local
_, err = ExecPodman(dest, podman, saveCmd)
if err != nil {
return nil, nil, nil, nil, err
}
rep, id, err := LoadToRemote(dest, source.File, "", sshInfo.URI[0], sshInfo.Identities[0], sshMode)
if err != nil {
return nil, nil, nil, nil, err
}
if len(rep) > 0 {
fmt.Println(rep)
}
if len(id) > 0 {
report.Names = append(report.Names, id)
}
if err = os.Remove(source.File); err != nil {
return nil, nil, nil, nil, err
}
default: // else native load, both source and dest are local and transferring between users
if source.User == "" { // source user has to be set, destination does not
source.User = os.Getenv("USER")
if source.User == "" {
u, err := user.Current()
if err != nil {
return nil, nil, nil, nil, fmt.Errorf("could not obtain user, make sure the environmental variable $USER is set: %w", err)
}
source.User = u.Username
}
}
return nil, &source, &dest, parentFlags, nil // transfer needs to be done in ABI due to cross issues
}
return &report, nil, nil, nil, nil
}
// CreateSCPCommand takes an existing command, appends the given arguments and returns a configured podman command for image scp
func CreateSCPCommand(cmd *exec.Cmd, command []string) *exec.Cmd {
cmd.Args = append(cmd.Args, command...)
cmd.Env = os.Environ()
cmd.Stderr = os.Stderr
cmd.Stdout = os.Stdout
return cmd
}
// ScpTag is a helper function for native podman to tag an image after a local load from image SCP
func ScpTag(cmd *exec.Cmd, podman string, dest entities.ImageScpOptions) error {
cmd.Stdout = nil
out, err := cmd.Output() // this function captures the output temporarily in order to execute the next command
if err != nil {
return err
}
image := ExtractImage(out)
if cmd.Args[0] == "sudo" { // transferRootless will need the sudo since we are loading to sudo from a user acct
cmd = exec.Command("sudo", podman, "tag", image, dest.Tag)
} else {
cmd = exec.Command(podman, "tag", image, dest.Tag)
}
cmd.Stdout = os.Stdout
return cmd.Run()
}
// ExtractImage pulls out the last line of output from save/load (image id)
func ExtractImage(out []byte) string {
fmt.Println(strings.TrimSuffix(string(out), "\n")) // print output
stringOut := string(out) // get all output
arrOut := strings.Split(stringOut, " ") // split it into an array
return strings.ReplaceAll(arrOut[len(arrOut)-1], "\n", "") // replace the trailing \n
}
// LoginUser starts the user process on the host so that image scp can use systemd-run
func LoginUser(user string) (*exec.Cmd, error) {
sleep, err := exec.LookPath("sleep")
if err != nil {
return nil, err
}
machinectl, err := exec.LookPath("machinectl")
if err != nil {
return nil, err
}
cmd := exec.Command(machinectl, "shell", "-q", user+"@.host", sleep, "inf")
err = cmd.Start()
return cmd, err
}
// loadToRemote takes image and remote connection information. it connects to the specified client
// and copies the saved image dir over to the remote host and then loads it onto the machine
// returns a string containing output or an error
func LoadToRemote(dest entities.ImageScpOptions, localFile string, tag string, url *url.URL, iden string, sshEngine ssh.EngineMode) (string, string, error) {
port, err := strconv.Atoi(url.Port())
if err != nil {
return "", "", err
}
remoteFile, err := ssh.Exec(&ssh.ConnectionExecOptions{Host: url.String(), Identity: iden, Port: port, User: url.User, Args: []string{"mktemp"}}, sshEngine)
if err != nil {
return "", "", err
}
opts := ssh.ConnectionScpOptions{User: url.User, Identity: iden, Port: port, Source: localFile, Destination: "ssh://" + url.User.String() + "@" + url.Hostname() + ":" + remoteFile}
scpRep, err := ssh.Scp(&opts, sshEngine)
if err != nil {
return "", "", err
}
out, err := ssh.Exec(&ssh.ConnectionExecOptions{Host: url.String(), Identity: iden, Port: port, User: url.User, Args: []string{"podman", "image", "load", "--input=" + scpRep + ";", "rm", scpRep}}, sshEngine)
if err != nil {
return "", "", err
}
if tag != "" {
return "", "", fmt.Errorf("renaming of an image is currently not supported: %w", define.ErrInvalidArg)
}
rep := strings.TrimSuffix(out, "\n")
outArr := strings.Split(rep, " ")
id := outArr[len(outArr)-1]
if len(dest.Tag) > 0 { // tag the remote image using the output ID
_, err := ssh.Exec(&ssh.ConnectionExecOptions{Host: url.String(), Identity: iden, Port: port, User: url.User, Args: []string{"podman", "image", "tag", id, dest.Tag}}, sshEngine)
if err != nil {
return "", "", err
}
if err != nil {
return "", "", err
}
}
return rep, id, nil
}
// saveToRemote takes image information and remote connection information. it connects to the specified client
// and saves the specified image on the remote machine and then copies it to the specified local location
// returns an error if one occurs.
func SaveToRemote(image, localFile string, tag string, uri *url.URL, iden string, sshEngine ssh.EngineMode) error {
if tag != "" {
return fmt.Errorf("renaming of an image is currently not supported: %w", define.ErrInvalidArg)
}
port, err := strconv.Atoi(uri.Port())
if err != nil {
return err
}
remoteFile, err := ssh.Exec(&ssh.ConnectionExecOptions{Host: uri.String(), Identity: iden, Port: port, User: uri.User, Args: []string{"mktemp"}}, sshEngine)
if err != nil {
return err
}
_, err = ssh.Exec(&ssh.ConnectionExecOptions{Host: uri.String(), Identity: iden, Port: port, User: uri.User, Args: []string{"podman", "image", "save", image, "--format", "oci-archive", "--output", remoteFile}}, sshEngine)
if err != nil {
return err
}
opts := ssh.ConnectionScpOptions{User: uri.User, Identity: iden, Port: port, Source: "ssh://" + uri.User.String() + "@" + uri.Hostname() + ":" + remoteFile, Destination: localFile}
scpRep, err := ssh.Scp(&opts, sshEngine)
if err != nil {
return err
}
_, err = ssh.Exec(&ssh.ConnectionExecOptions{Host: uri.String(), Identity: iden, Port: port, User: uri.User, Args: []string{"rm", scpRep}}, sshEngine)
if err != nil {
logrus.Errorf("Removing file on endpoint: %v", err)
}
return nil
}
// execPodman executes the podman save/load command given the podman binary
func ExecPodman(dest entities.ImageScpOptions, podman string, command []string) (string, error) {
cmd := exec.Command(podman)
CreateSCPCommand(cmd, command[1:])
logrus.Debugf("Executing podman command: %q", cmd)
if strings.Contains(strings.Join(command, " "), "load") { // need to tag
if len(dest.Tag) > 0 {
return "", ScpTag(cmd, podman, dest)
}
cmd.Stdout = nil
out, err := cmd.Output()
if err != nil {
return "", err
}
img := ExtractImage(out)
return img, nil
}
return "", cmd.Run()
}
// createCommands forms the podman save and load commands used by SCP
func CreateCommands(source entities.ImageScpOptions, dest entities.ImageScpOptions, parentFlags []string, podman string) ([]string, []string) {
var parentString string
quiet := ""
if source.Quiet {
quiet = "-q "
}
if len(parentFlags) > 0 {
parentString = strings.Join(parentFlags, " ") + " " // if there are parent args, an extra space needs to be added
} else {
parentString = strings.Join(parentFlags, " ")
}
loadCmd := strings.Split(fmt.Sprintf("%s %sload %s--input %s", podman, parentString, quiet, dest.File), " ")
saveCmd := strings.Split(fmt.Sprintf("%s %vsave %s--output %s %s", podman, parentString, quiet, source.File, source.Image), " ")
return saveCmd, loadCmd
}
// parseImageSCPArg returns the valid connection, and source/destination data based off of the information provided by the user
// arg is a string containing one of the cli arguments returned is a filled out source/destination options structs as well as a connections array and an error if applicable
func ParseImageSCPArg(arg string) (*entities.ImageScpOptions, []string, error) {
location := entities.ImageScpOptions{}
var err error
cliConnections := []string{}
switch {
case strings.Contains(arg, "@localhost::"): // image transfer between users
location.User = strings.Split(arg, "@")[0]
location, err = ValidateImagePortion(location, arg)
if err != nil {
return nil, nil, err
}
cliConnections = append(cliConnections, arg)
case strings.Contains(arg, "::"):
location, err = ValidateImagePortion(location, arg)
if err != nil {
return nil, nil, err
}
location.Remote = true
cliConnections = append(cliConnections, arg)
default:
location.Image = arg
}
return &location, cliConnections, nil
}
func ValidateImagePortion(location entities.ImageScpOptions, arg string) (entities.ImageScpOptions, error) {
if RemoteArgLength(arg, 1) > 0 {
before := strings.Split(arg, "::")[1]
name := ValidateImageName(before)
if before != name {
location.Image = name
} else {
location.Image = before
} // this will get checked/set again once we validate connections
}
return location, nil
}
// validateImageName makes sure that the image given is valid and no injections are occurring
// we simply use this for error checking, bot setting the image
func ValidateImageName(input string) string {
// ParseNormalizedNamed transforms a shortname image into its
// full name reference so busybox => docker.io/library/busybox
// we want to keep our shortnames, so only return an error if
// we cannot parse what the user has given us
if ref, err := alltransports.ParseImageName(input); err == nil {
return ref.Transport().Name()
}
return input
}
// validateSCPArgs takes the array of source and destination options and checks for common errors
func ValidateSCPArgs(locations []*entities.ImageScpOptions) error {
if len(locations) > 2 {
return fmt.Errorf("cannot specify more than two arguments: %w", define.ErrInvalidArg)
}
switch {
case len(locations[0].Image) > 0 && len(locations[1].Image) > 0:
locations[1].Tag = locations[1].Image
locations[1].Image = ""
case len(locations[0].Image) == 0 && len(locations[1].Image) == 0:
return fmt.Errorf("a source image must be specified: %w", define.ErrInvalidArg)
}
return nil
}
// remoteArgLength is a helper function to simplify the extracting of host argument data
// returns an int which contains the length of a specified index in a host::image string
func RemoteArgLength(input string, side int) int {
if strings.Contains(input, "::") {
return len((strings.Split(input, "::"))[side])
}
return -1
}
// GetServiceInformation takes the parsed list of hosts to connect to and validates the information
func GetServiceInformation(sshInfo *entities.ImageScpConnections, cliConnections []string, cfg *config.Config) error {
var urlS string
var iden string
for i, val := range cliConnections {
connection, _, _ := strings.Cut(val, "::")
sshInfo.Connections = append(sshInfo.Connections, connection)
conn, err := cfg.GetConnection(sshInfo.Connections[i], false)
if err == nil {
// connection found
urlS = conn.URI
iden = conn.Identity
} else { // no match, warn user and do a manual connection.
urlS = "ssh://" + sshInfo.Connections[i]
iden = ""
logrus.Warnf("Unknown connection name given. Please use system connection add to specify the default remote socket location")
}
urlFinal, err := url.Parse(urlS) // create an actual url to pass to exec command
if err != nil {
return err
}
if urlFinal.User.Username() == "" {
if urlFinal.User, err = GetUserInfo(urlFinal); err != nil {
return err
}
}
sshInfo.URI = append(sshInfo.URI, urlFinal)
sshInfo.Identities = append(sshInfo.Identities, iden)
}
return nil
}
func GetUserInfo(uri *url.URL) (*url.Userinfo, error) {
var (
usr *user.User
err error
)
if u, found := os.LookupEnv("_CONTAINERS_ROOTLESS_UID"); found {
usr, err = user.LookupId(u)
if err != nil {
return nil, fmt.Errorf("failed to lookup rootless user: %w", err)
}
} else {
usr, err = user.Current()
if err != nil {
return nil, fmt.Errorf("failed to obtain current user: %w", err)
}
}
pw, set := uri.User.Password()
if set {
return url.UserPassword(usr.Username, pw), nil
}
return url.User(usr.Username), nil
}