diff options
Diffstat (limited to 'cmd/podman/system/connection.go')
-rw-r--r-- | cmd/podman/system/connection.go | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/cmd/podman/system/connection.go b/cmd/podman/system/connection.go new file mode 100644 index 000000000..d8c709d6e --- /dev/null +++ b/cmd/podman/system/connection.go @@ -0,0 +1,209 @@ +package system + +import ( + "bytes" + "fmt" + "net" + "net/url" + "os" + "os/user" + "regexp" + + "github.com/containers/common/pkg/config" + "github.com/containers/libpod/cmd/podman/registry" + "github.com/containers/libpod/libpod/define" + "github.com/containers/libpod/pkg/domain/entities" + "github.com/containers/libpod/pkg/terminal" + "github.com/pkg/errors" + "github.com/sirupsen/logrus" + "github.com/spf13/cobra" + "golang.org/x/crypto/ssh" + "golang.org/x/crypto/ssh/agent" +) + +const schemaPattern = "^[A-Za-z][A-Za-z0-9+.-]*:" + +var ( + // Skip creating engines since this command will obtain connection information to engine + noOp = func(cmd *cobra.Command, args []string) error { + return nil + } + connectionCmd = &cobra.Command{ + Use: "connection [flags] destination", + Args: cobra.ExactArgs(1), + Long: `Store ssh destination information in podman configuration. + "destination" is of the form [user@]hostname or + an URI of the form ssh://[user@]hostname[:port] +`, + Short: "Record remote ssh destination", + PersistentPreRunE: noOp, + PersistentPostRunE: noOp, + TraverseChildren: false, + RunE: connection, + Example: `podman system connection server.fubar.com + podman system connection --identity ~/.ssh/dev_rsa ssh://root@server.fubar.com:2222 + podman system connection --identity ~/.ssh/dev_rsa -port 22 root@server.fubar.com`, + } + + cOpts = struct { + Identity string + Port int + UDSPath string + }{} +) + +func init() { + registry.Commands = append(registry.Commands, registry.CliCommand{ + Mode: []entities.EngineMode{entities.ABIMode, entities.TunnelMode}, + Command: connectionCmd, + Parent: systemCmd, + }) + + flags := connectionCmd.Flags() + flags.StringVar(&cOpts.Identity, "identity", "", "path to ssh identity file") + flags.IntVarP(&cOpts.Port, "port", "p", 22, "port number for destination") + flags.StringVar(&cOpts.UDSPath, "socket-path", "", "path to podman socket on remote host. (default '/run/podman/podman.sock' or '/run/user/{uid}/podman/podman.sock)") +} + +func connection(cmd *cobra.Command, args []string) error { + // Default to ssh: schema if none given + dest := []byte(args[0]) + if match, err := regexp.Match(schemaPattern, dest); err != nil { + return errors.Wrapf(err, "internal regex error %q", schemaPattern) + } else if !match { + dest = append([]byte("ssh://"), dest...) + } + + uri, err := url.Parse(string(dest)) + if err != nil { + return errors.Wrapf(err, "failed to parse %q", string(dest)) + } + + if uri.User.Username() == "" { + if uri.User, err = getUserInfo(uri); err != nil { + return err + } + } + + if cmd.Flag("socket-path").Changed { + uri.Path = cmd.Flag("socket-path").Value.String() + } + + if cmd.Flag("port").Changed { + uri.Host = net.JoinHostPort(uri.Hostname(), cmd.Flag("port").Value.String()) + } + + if uri.Port() == "" { + uri.Host = net.JoinHostPort(uri.Hostname(), cmd.Flag("port").DefValue) + } + + if uri.Path == "" { + if uri.Path, err = getUDS(cmd, uri); err != nil { + return errors.Wrapf(err, "failed to connect to %q", uri.String()) + } + } + + custom, err := config.ReadCustomConfig() + if err != nil { + return err + } + + if cmd.Flag("identity").Changed { + custom.Engine.RemoteIdentity = cOpts.Identity + } + + custom.Engine.RemoteURI = uri.String() + return custom.Write() +} + +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, errors.Wrapf(err, "failed to find user %q", u) + } + } else { + usr, err = user.Current() + if err != nil { + return nil, errors.Wrapf(err, "failed to obtain current user") + } + } + + pw, set := uri.User.Password() + if set { + return url.UserPassword(usr.Username, pw), nil + } + return url.User(usr.Username), nil +} + +func getUDS(cmd *cobra.Command, uri *url.URL) (string, error) { + var authMethods []ssh.AuthMethod + passwd, set := uri.User.Password() + if set { + authMethods = append(authMethods, ssh.Password(passwd)) + } + + ident := cmd.Flag("identity") + if ident.Changed { + auth, err := terminal.PublicKey(ident.Value.String(), []byte(passwd)) + if err != nil { + return "", errors.Wrapf(err, "Failed to read identity %q", ident.Value.String()) + } + authMethods = append(authMethods, auth) + } + + if sock, found := os.LookupEnv("SSH_AUTH_SOCK"); found { + logrus.Debugf("Found SSH_AUTH_SOCK %q, ssh-agent signer enabled", sock) + + c, err := net.Dial("unix", sock) + if err != nil { + return "", err + } + a := agent.NewClient(c) + authMethods = append(authMethods, ssh.PublicKeysCallback(a.Signers)) + } + + config := &ssh.ClientConfig{ + User: uri.User.Username(), + Auth: authMethods, + HostKeyCallback: ssh.InsecureIgnoreHostKey(), + } + dial, err := ssh.Dial("tcp", uri.Host, config) + if err != nil { + return "", errors.Wrapf(err, "failed to connect to %q", uri.Host) + } + defer dial.Close() + + session, err := dial.NewSession() + if err != nil { + return "", errors.Wrapf(err, "failed to create new ssh session on %q", uri.Host) + } + defer session.Close() + + // Override podman binary for testing etc + podman := "podman" + if v, found := os.LookupEnv("PODMAN_BINARY"); found { + podman = v + } + run := podman + " info --format=json" + + var buffer bytes.Buffer + session.Stdout = &buffer + if err := session.Run(run); err != nil { + return "", errors.Wrapf(err, "failed to run %q", run) + } + + var info define.Info + if err := json.Unmarshal(buffer.Bytes(), &info); err != nil { + return "", errors.Wrapf(err, "failed to parse 'podman info' results") + } + + if info.Host.RemoteSocket == nil || !info.Host.RemoteSocket.Exists { + return "", fmt.Errorf("remote podman %q failed to report its UDS socket", uri.Host) + } + return info.Host.RemoteSocket.Path, nil +} |