Delete userdata from VirtualBox/VMware after Ignition completes

Makefile

@@ -23,8 +23,11 @@ install: all
 	  install -m 0644 -D -t $(DESTDIR)/usr/lib/dracut/modules.d/$${bn} $$x/*; \
 	done
 	chmod a+x $(DESTDIR)/usr/lib/dracut/modules.d/*/*.sh $(DESTDIR)/usr/lib/dracut/modules.d/*/*-generator
+	install -m 0644 -D -t $(DESTDIR)/usr/lib/systemd/system systemd/ignition-delete-config.service
 	install -m 0755 -D -t $(DESTDIR)/usr/lib/dracut/modules.d/30ignition bin/$(GOARCH)/ignition
 	install -m 0755 -D -t $(DESTDIR)/usr/bin bin/$(GOARCH)/ignition-validate
+	install -m 0755 -d $(DESTDIR)/usr/libexec
+	ln -sf ../lib/dracut/modules.d/30ignition/ignition $(DESTDIR)/usr/libexec/ignition-rmcfg
 
 .PHONY: vendor
 vendor:

go.mod

@@ -6,18 +6,17 @@ require (
 	cloud.google.com/go v0.58.0
 	cloud.google.com/go/storage v1.9.0
 	github.com/aws/aws-sdk-go v1.30.28
+	github.com/beevik/etree v1.1.1-0.20200718192613-4a2f8b9d084c
 	github.com/coreos/go-semver v0.3.0
 	github.com/coreos/go-systemd/v22 v22.0.0
 	github.com/coreos/vcontext v0.0.0-20211021162308-f1dbbca7bef4
 	github.com/google/renameio v0.1.0
 	github.com/google/uuid v1.1.1
 	github.com/pin/tftp v2.1.0+incompatible
-	github.com/smartystreets/goconvey v0.0.0-20190222223459-a17d461953aa // indirect
 	github.com/spf13/pflag v1.0.6-0.20210604193023-d5e0c0615ace
 	github.com/stretchr/testify v1.7.0
 	github.com/vincent-petithory/dataurl v1.0.0
 	github.com/vmware/vmw-guestinfo v0.0.0-20220317130741-510905f0efa3
-	github.com/vmware/vmw-ovflib v0.0.0-20170608004843-1f217b9dc714
 	go.opencensus.io v0.22.5 // indirect
 	golang.org/x/net v0.0.0-20200602114024-627f9648deb9
 	golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d

go.sum

@@ -40,6 +40,8 @@ github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03
 github.com/BurntSushi/xgb v0.0.0-20160522181843-27f122750802/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=
 github.com/aws/aws-sdk-go v1.30.28 h1:SaPM7dlmp7h3Lj1nJ4jdzOkTdom08+g20k7AU5heZYg=
 github.com/aws/aws-sdk-go v1.30.28/go.mod h1:5zCpMtNQVjRREroY7sYe8lOMRSxkhG6MZveU8YkpAk0=
+github.com/beevik/etree v1.1.1-0.20200718192613-4a2f8b9d084c h1:uYq6BD31fkfeNKQmfLj7ODcEfkb5JLsKrXVSqgnfGg8=
+github.com/beevik/etree v1.1.1-0.20200718192613-4a2f8b9d084c/go.mod h1:0yGO2rna3S9DkITDWHY1bMtcY4IJ4w+4S+EooZUR0bE=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
 github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
@@ -115,8 +117,6 @@ github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5 h1:sjZBwGj9Jlw33ImPtvFviGYvseOtDM7hkSKB7+Tv3SM=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
-github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1 h1:EGx4pi6eqNxGaHF6qqu48+N2wcFQ5qg5FXgOdqsJ5d8=
-github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/hashicorp/golang-lru v0.5.0/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/hashicorp/golang-lru v0.5.1/go.mod h1:/m3WP610KZHVQ1SGc6re/UDhFvYD7pJ4Ao+sR/qLZy8=
 github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
@@ -125,8 +125,6 @@ github.com/jmespath/go-jmespath v0.3.0/go.mod h1:9QtRXoHjLGCJ5IBSaohpXITPlowMeeY
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
 github.com/jstemmer/go-junit-report v0.9.1 h1:6QPYqodiu3GuPL+7mfx+NwDdp2eTkp9IfEUpgAwUN0o=
 github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/XSXhF0NWZEnDohbsk=
-github.com/jtolds/gls v4.2.1+incompatible h1:fSuqC+Gmlu6l/ZYAoZzx2pyucC8Xza35fpRVWLVmUEE=
-github.com/jtolds/gls v4.2.1+incompatible/go.mod h1:QJZ7F/aHp+rZTRtaJ1ow/lLfFfVYBRgL+9YlvaHOwJU=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
@@ -140,10 +138,6 @@ github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZb
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
-github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d h1:zE9ykElWQ6/NYmHa3jpm/yHnI4xSofP+UP6SpjHcSeM=
-github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d/go.mod h1:OnSkiWE9lh6wB0YB77sQom3nweQdgAjqCqsofrRNTgc=
-github.com/smartystreets/goconvey v0.0.0-20190222223459-a17d461953aa h1:E+gaaifzi2xF65PbDmuKI3PhLWY6G5opMLniFq8vmXA=
-github.com/smartystreets/goconvey v0.0.0-20190222223459-a17d461953aa/go.mod h1:2RVY1rIf+2J2o/IM9+vPq9RzmHDSseB7FoXiSNIUsoU=
 github.com/spf13/pflag v1.0.6-0.20210604193023-d5e0c0615ace h1:9PNP1jnUjRhfmGMlkXHjYPishpcw4jpSt/V/xYY3FMA=
 github.com/spf13/pflag v1.0.6-0.20210604193023-d5e0c0615ace/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
@@ -155,8 +149,6 @@ github.com/vincent-petithory/dataurl v1.0.0 h1:cXw+kPto8NLuJtlMsI152irrVw9fRDX8A
 github.com/vincent-petithory/dataurl v1.0.0/go.mod h1:FHafX5vmDzyP+1CQATJn7WFKc9CvnvxyvZy6I1MrG/U=
 github.com/vmware/vmw-guestinfo v0.0.0-20220317130741-510905f0efa3 h1:v6jG/tdl4O07LNVp74Nt7/OyL+1JsIW1M2f/nSvQheY=
 github.com/vmware/vmw-guestinfo v0.0.0-20220317130741-510905f0efa3/go.mod h1:CSBTxrhePCm0cmXNKDGeu+6bOQzpaEklfCqEpn89JWk=
-github.com/vmware/vmw-ovflib v0.0.0-20170608004843-1f217b9dc714 h1:wJqF3m4Tj8I4beSi6vGxIyNtsq6wwGqhK3UnA99ltL4=
-github.com/vmware/vmw-ovflib v0.0.0-20170608004843-1f217b9dc714/go.mod h1:jiPk45kn7klhByRvUq5i2vo1RtHKBHj+iWGFpxbXuuI=
 github.com/yuin/goldmark v1.1.25/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=

internal/main.go

@@ -41,10 +41,13 @@ import (
 )
 
 func main() {
-	if filepath.Base(os.Args[0]) == "ignition-apply" {
+	switch filepath.Base(os.Args[0]) {
+	case "ignition-apply":
 		ignitionApplyMain()
-	} else {
-		// otherwise, assume regular Ignition
+	case "ignition-rmcfg":
+		ignitionRmCfgMain()
+	default:
+		// assume regular Ignition
 		ignitionMain()
 	}
 }
@@ -187,3 +190,54 @@ func ignitionApplyMain() {
 		os.Exit(1)
 	}
 }
+
+func ignitionRmCfgMain() {
+	flags := struct {
+		logToStdout bool
+		platform    string
+		version     bool
+	}{}
+	pflag.StringVar(&flags.platform, "platform", "", fmt.Sprintf("current platform. %v", platform.Names()))
+	pflag.BoolVar(&flags.logToStdout, "log-to-stdout", false, "log to stdout instead of the system log")
+	pflag.BoolVar(&flags.version, "version", false, "print the version and exit")
+	pflag.Usage = func() {
+		fmt.Fprintf(pflag.CommandLine.Output(), "Usage: %s [options]\n", os.Args[0])
+		fmt.Fprintf(pflag.CommandLine.Output(), "Options:\n")
+		pflag.PrintDefaults()
+	}
+	pflag.Parse()
+
+	if flags.version {
+		fmt.Printf("%s\n", version.String)
+		return
+	}
+
+	if pflag.NArg() != 0 {
+		pflag.Usage()
+		os.Exit(2)
+	}
+
+	if flags.platform == "" {
+		fmt.Fprint(os.Stderr, "'--platform' must be provided\n")
+		os.Exit(2)
+	}
+
+	logger := log.New(flags.logToStdout)
+	defer logger.Close()
+
+	logger.Info(version.String)
+
+	platformConfig := platform.MustGet(flags.platform)
+	fetcher, err := platformConfig.NewFetcherFunc()(&logger)
+	if err != nil {
+		logger.Crit("failed to generate fetcher: %s", err)
+		os.Exit(3)
+	}
+
+	if err := platformConfig.DelConfig(&fetcher); err != nil {
+		logger.Crit("couldn't delete config: %s", err)
+		os.Exit(1)
+	}
+
+	logger.Info("Successfully deleted config")
+}

internal/platform/platform.go

@@ -15,6 +15,7 @@
 package platform
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/coreos/ignition/v2/internal/log"
@@ -44,13 +45,18 @@ import (
 	"github.com/coreos/ignition/v2/internal/resource"
 )
 
+var (
+	ErrCannotDelete = errors.New("cannot delete config on this platform")
+)
+
 // Config represents a set of options that map to a particular platform.
 type Config struct {
 	name       string
 	fetch      providers.FuncFetchConfig
 	init       providers.FuncInit
 	newFetcher providers.FuncNewFetcher
 	status     providers.FuncPostStatus
+	delConfig  providers.FuncDelConfig
 }
 
 func (c Config) Name() string {
@@ -93,6 +99,14 @@ func (c Config) Status(stageName string, f resource.Fetcher, statusErr error) er
 	return nil
 }
 
+func (c Config) DelConfig(f *resource.Fetcher) error {
+	if c.delConfig != nil {
+		return c.delConfig(f)
+	} else {
+		return ErrCannotDelete
+	}
+}
+
 var configs = registry.Create("platform configs")
 
 func init() {
@@ -172,12 +186,14 @@ func init() {
 		fetch: qemu.FetchConfig,
 	})
 	configs.Register(Config{
-		name:  "virtualbox",
-		fetch: virtualbox.FetchConfig,
+		name:      "virtualbox",
+		fetch:     virtualbox.FetchConfig,
+		delConfig: virtualbox.DelConfig,
 	})
 	configs.Register(Config{
-		name:  "vmware",
-		fetch: vmware.FetchConfig,
+		name:      "vmware",
+		fetch:     vmware.FetchConfig,
+		delConfig: vmware.DelConfig,
 	})
 	configs.Register(Config{
 		name:  "vultr",

internal/providers/providers.go

@@ -32,3 +32,4 @@ type FuncFetchConfig func(f *resource.Fetcher) (types.Config, report.Report, err
 type FuncInit func(f *resource.Fetcher) error
 type FuncNewFetcher func(logger *log.Logger) (resource.Fetcher, error)
 type FuncPostStatus func(stageName string, f resource.Fetcher, e error) error
+type FuncDelConfig func(f *resource.Fetcher) error

internal/providers/virtualbox/virtualbox.c

@@ -24,6 +24,10 @@
 #include <errno.h>
 #include "virtualbox.h"
 
+// From virtualbox/include/VBox/HostServices/GuestPropertySvc.h
+#define GUEST_PROP_FN_GET_PROP 1
+#define GUEST_PROP_FN_DEL_PROP 4
+
 static void _cleanup_close(int *fd) {
 	if (*fd != -1) {
 		close(*fd);
@@ -86,13 +90,16 @@ static int connect(int fd, uint32_t *client_id) {
 }
 
 static int get_prop(int fd, uint32_t client_id, const char *name, void **value, size_t *size) {
+	// xref VbglR3GuestPropRead() in
+	// virtualbox/src/VBox/Additions/common/VBoxGuest/lib/VBoxGuestR3LibGuestProp.cpp
+
 	// init header
 	size_t msg_size = sizeof(struct vbg_ioctl_hgcm_call) + 4 * sizeof(struct vmmdev_hgcm_function_parameter64);
 	struct vbg_ioctl_hgcm_call _cleanup_free_ *msg = calloc(1, msg_size);
 	// init_header re-adds the size of msg->hdr
 	init_header(&msg->hdr, msg_size - sizeof(msg->hdr), msg_size - sizeof(msg->hdr));
 	msg->client_id = client_id;
-	msg->function = 1;     // GUEST_PROP_FN_GET_PROP
+	msg->function = GUEST_PROP_FN_GET_PROP;
 	msg->timeout_ms = -1;  // inf
 	msg->interruptible = 1;
 	msg->parm_count = 4;
@@ -147,6 +154,38 @@ static int get_prop(int fd, uint32_t client_id, const char *name, void **value,
 	}
 }
 
+static int del_prop(int fd, uint32_t client_id, const char *name) {
+	// xref VbglR3GuestPropDelete() in
+	// virtualbox/src/VBox/Additions/common/VBoxGuest/lib/VBoxGuestR3LibGuestProp.cpp
+
+	// init header
+	size_t msg_size = sizeof(struct vbg_ioctl_hgcm_call) + sizeof(struct vmmdev_hgcm_function_parameter64);
+	struct vbg_ioctl_hgcm_call _cleanup_free_ *msg = calloc(1, msg_size);
+	// init_header re-adds the size of msg->hdr
+	init_header(&msg->hdr, msg_size - sizeof(msg->hdr), msg_size - sizeof(msg->hdr));
+	msg->client_id = client_id;
+	msg->function = GUEST_PROP_FN_DEL_PROP;
+	msg->timeout_ms = -1;  // inf
+	msg->interruptible = 1;
+	msg->parm_count = 1;
+
+	// init arguments
+	struct vmmdev_hgcm_function_parameter64 *params = (void *) (msg + 1);
+	// property name (in)
+	params[0].type = VMMDEV_HGCM_PARM_TYPE_LINADDR_IN;
+	params[0].u.pointer.size = strlen(name) + 1;
+	params[0].u.pointer.u.linear_addr = (uintptr_t) name;
+
+	// delete value
+	if (ioctl(fd, VBG_IOCTL_HGCM_CALL_64(msg_size), msg)) {
+		return VERR_GENERAL_FAILURE;
+	}
+	if (msg->hdr.rc != VINF_SUCCESS) {
+		return msg->hdr.rc;
+	}
+	return VINF_SUCCESS;
+}
+
 static int disconnect(int fd, uint32_t client_id) {
 	struct vbg_ioctl_hgcm_disconnect msg = {
 		.u = {
@@ -162,7 +201,7 @@ static int disconnect(int fd, uint32_t client_id) {
 	return msg.hdr.rc;
 }
 
-int virtualbox_get_guest_property(char *name, void **value, size_t *size) {
+static int start_connection(uint32_t *client_id) {
 	// clear any previous garbage in errno for error returns
 	errno = 0;
 
@@ -179,12 +218,26 @@ int virtualbox_get_guest_property(char *name, void **value, size_t *size) {
 	}
 
 	// connect to property service
-	uint32_t client_id;
-	ret = connect(fd, &client_id);
+	ret = connect(fd, client_id);
 	if (ret != VINF_SUCCESS) {
 		return ret;
 	}
 
+	// return fd
+	ret = fd;
+	fd = -1;
+	return ret;
+}
+
+int virtualbox_get_guest_property(char *name, void **value, size_t *size) {
+	// connect
+	uint32_t client_id;
+	int ret = start_connection(&client_id);
+	if (ret < 0) {
+		return ret;
+	}
+	int _cleanup_close_ fd = ret;
+
 	// get property
 	ret = get_prop(fd, client_id, name, value, size);
 	if (ret != VINF_SUCCESS) {
@@ -206,3 +259,32 @@ int virtualbox_get_guest_property(char *name, void **value, size_t *size) {
 	errno = 0;
 	return 0;
 }
+
+int virtualbox_delete_guest_property(char *name) {
+	// connect
+	uint32_t client_id;
+	int ret = start_connection(&client_id);
+	if (ret < 0) {
+		return ret;
+	}
+	int _cleanup_close_ fd = ret;
+
+	// delete property
+	ret = del_prop(fd, client_id, name);
+	if (ret != VINF_SUCCESS) {
+		disconnect(fd, client_id);
+		return ret;
+	}
+
+	// disconnect
+	ret = disconnect(fd, client_id);
+	if (ret != VINF_SUCCESS) {
+		// we could ignore the failure, but better to make sure bugs
+		// are noticed
+		return ret;
+	}
+
+	// for clarity, ensure the Go error return is nil
+	errno = 0;
+	return 0;
+}

internal/providers/virtualbox/virtualbox.go

@@ -69,6 +69,19 @@ func FetchConfig(f *resource.Fetcher) (types.Config, report.Report, error) {
 	return util.ParseConfig(f.Logger, config)
 }
 
+func DelConfig(f *resource.Fetcher) error {
+	f.Logger.Info("deleting Ignition config from VirtualBox guest property")
+	err := deleteProperty(configEncodingProperty)
+	if err != nil {
+		return err
+	}
+	err = deleteProperty(configProperty)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func fetchProperty(name string) ([]byte, error) {
 	cName := C.CString(name)
 	defer C.free(unsafe.Pointer(cName))
@@ -90,3 +103,21 @@ func fetchProperty(name string) ([]byte, error) {
 	// properties are double-NUL-terminated
 	return bytes.TrimRight(C.GoBytes(buf, C.int(size)), "\x00"), nil
 }
+
+func deleteProperty(name string) error {
+	cName := C.CString(name)
+	defer C.free(unsafe.Pointer(cName))
+
+	ret, errno := C.virtualbox_delete_guest_property(cName)
+	if ret != C.VINF_SUCCESS {
+		if ret == C.VERR_GENERAL_FAILURE && errno != nil {
+			return fmt.Errorf("deleting VirtualBox guest property %q: %w", name, errno)
+		}
+		if ret == C.VERR_PERMISSION_DENIED {
+			return fmt.Errorf("deleting VirtualBox guest property %q: permission denied; is the property read-only?", name)
+		}
+		// see <linux/vbox_err.h>
+		return fmt.Errorf("deleting VirtualBox guest property %q: error %d", name, ret)
+	}
+	return nil
+}