diff mbox series

[isar-cip-core,v3,1/3] Add Delta update support with rdiff_image and delta handler

Message ID 20240415104610.3073497-2-Adithya.Balakumar@toshiba-tsip.com (mailing list archive)
State Superseded
Headers show
Series Integrate Delta Update with rdiff_image and delta handler | expand

Commit Message

Adithya Balakumar April 15, 2024, 10:46 a.m. UTC 
swupdate supports delta updates with rdiff_image and delta(zchunk)
handler. This change adds support to use either of the handler
for creating delta update artifacts. zchunk based updates are supported
only for sid.

DELTA_UPDATE_TYPE, DELTA_RDIFF_REF_IMAGE and DELTA_ZCK_URL variables can
be modified based on the update type in the swupdate.yml file.

Signed-off-by: Adithya Balakumar <Adithya.Balakumar@toshiba-tsip.com>
---
 classes/delta-update.bbclass | 97 ++++++++++++++++++++++++++++++++++++
 conf/layer.conf              |  2 +-
 kas/opt/swupdate.yml         |  6 +++
 3 files changed, 104 insertions(+), 1 deletion(-)
 create mode 100644 classes/delta-update.bbclass

Comments

Felix Moessbauer April 16, 2024, 4:11 a.m. UTC | #1 
On Mon, 2024-04-15 at 16:16 +0530, Adithya Balakumar wrote:
> swupdate supports delta updates with rdiff_image and delta(zchunk)
> handler. This change adds support to use either of the handler
> for creating delta update artifacts. zchunk based updates are
> supported
> only for sid.
> 
> DELTA_UPDATE_TYPE, DELTA_RDIFF_REF_IMAGE and DELTA_ZCK_URL variables
> can
> be modified based on the update type in the swupdate.yml file.
> 
> Signed-off-by: Adithya Balakumar <Adithya.Balakumar@toshiba-tsip.com>
> ---
>  classes/delta-update.bbclass | 97
> ++++++++++++++++++++++++++++++++++++
>  conf/layer.conf              |  2 +-
>  kas/opt/swupdate.yml         |  6 +++
>  3 files changed, 104 insertions(+), 1 deletion(-)
>  create mode 100644 classes/delta-update.bbclass
> 
> diff --git a/classes/delta-update.bbclass b/classes/delta-
> update.bbclass
> new file mode 100644
> index 0000000..87bf7ff
> --- /dev/null
> +++ b/classes/delta-update.bbclass
> @@ -0,0 +1,97 @@
> +#
> +# CIP Core, generic profile
> +#
> +# Copyright (c) Toshiba Corporation 2024
> +#
> +# Authors:
> +#  Adithya Balakumar <adithya.balakumar@toshiba-tsip.com>
> +#
> +# SPDX-License-Identifier: MIT
> +#
> +
> +IMAGER_INSTALL:delta_update .= "zchunk rdiff"

When appending with .=, prepend a space.

> +
> +FILESEXTRAPATHS:append = ":${TOPDIR}/previous-image"

Please always prepend to the filesextrapath to make sure this dir is
searched first.

Felix

> +do_image_delta_update[cleandirs] +=
> "${WORKDIR}/delta_interim_artifacts"
> +
> +DELTA_UPDATE_TYPE ??= "rdiff"
> +DELTA_RDIFF_REF_IMAGE ??= "${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}"
> +DELTA_ZCK_URL ??= ""
> +DELTA_PREV_IMAGE_PATH ??= "${TOPDIR}/previous-image"
> +
> +def disable_delta_update_tasks (d):
> +    d.appendVarFlag("do_image_delta_update", "noexec", "1")
> +    d.setVar("DELTA_UPDATE_TYPE", "")
> +
> +def delta_update_prereq_check (d):
> +    import os
> +    if d.getVar("DELTA_UPDATE_TYPE") == "rdiff":
> +        path = d.getVar("DELTA_PREV_IMAGE_PATH") + "/" +
> d.getVar("DELTA_RDIFF_REF_IMAGE")
> +        if not os.path.isfile(path):
> +            disable_delta_update_tasks(d)
> +        else:
> +            return "file://" + d.getVar("DELTA_RDIFF_REF_IMAGE")
> +    elif d.getVar("DELTA_UPDATE_TYPE") == "zchunk":
> +        if d.getVar("BASE_DISTRO_CODENAME") != "sid":
> +            disable_delta_update_tasks(d)
> +    else:
> +        disable_delta_update_tasks(d)
> +    return ""
> +
> +SRC_URI += "${@delta_update_prereq_check(d)}"
> +
> +create_rdiff_delta_artifact() {
> +    if [ -z "${DELTA_RDIFF_REF_IMAGE}" ]; then
> +        bbfatal "You must set DELTA_RDIFF_REF_IMAGE and provide the
> required files as artifacts to this recipe"
> +    fi
> +
> +    rm -f ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta
> +    # create signature file with rdiff
> +    ${SUDO_CHROOT} /usr/bin/rdiff signature
> ${WORKDIR}/${DELTA_RDIFF_REF_IMAGE} \
> +        ${WORKDIR}/delta_interim_artifacts/old-image-rootfs.sig
> +
> +    # create delta file with the signature file
> +    ${SUDO_CHROOT} /usr/bin/rdiff delta
> ${WORKDIR}/delta_interim_artifacts/old-image-rootfs.sig \
> +        ${PP_DEPLOY}/${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}
> ${PP_DEPLOY}/${IMAGE_FULLNAME}.delta
> +
> +    DELTA_ARTIFACT_SWU=${IMAGE_FULLNAME}.delta
> +
> +    # create a symbolic link as IMAGE_CMD expects a *.delta_update
> file in deploy image directory
> +    ln -sf ${DELTA_ARTIFACT_SWU}
> ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta_update
> +}
> +
> +create_zchunk_delta_artifact() {
> +    # Create .zck file
> +    ${SUDO_CHROOT} /bin/zck \
> +        --output ${PP_DEPLOY}/${IMAGE_FULLNAME}.zck \
> +        -u --chunk-hash-type sha256 \
> +        ${PP_DEPLOY}/${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}
> +
> +    # Calculate size of zck header
> +    HSIZE="$(${SUDO_CHROOT} /bin/zck_read_header -v
> ${PP_DEPLOY}/${IMAGE_FULLNAME}.zck | grep "Header size" | cut -d ':'
> -f 2)"
> +
> +    # Extract the zck header
> +    ${SUDO_CHROOT} /bin/dd if="${PP_DEPLOY}/${IMAGE_FULLNAME}".zck
> of="${PP_DEPLOY}/${IMAGE_FULLNAME}".zck.header bs=1 count="$HSIZE"
> status=none
> +
> +    DELTA_ARTIFACT_SWU=${IMAGE_FULLNAME}.zck.header
> +
> +    # create a symbolic link as IMAGE_CMD expects a *.delta_update
> file in deploy image directory
> +    ln -sf ${DELTA_ARTIFACT_SWU}
> ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta_update
> +}
> +
> +do_image_delta_update[depends] += "${PN}:do_transform_template"
> +IMAGE_CMD:delta_update() {
> +    case "${DELTA_UPDATE_TYPE}" in
> +    "rdiff")
> +        create_rdiff_delta_artifact
> +        ;;
> +    "zchunk")
> +        create_zchunk_delta_artifact
> +        ;;
> +    *)
> +        bbfatal "You must set a valid DELTA_UPDATE_TYPE
> (rdiff/zchunk)"
> +        ;;
> +    esac
> +}
> +
> +addtask do_image_delta_update before do_image_swu after do_image_wic
> diff --git a/conf/layer.conf b/conf/layer.conf
> index 6198e1b..c652a61 100644
> --- a/conf/layer.conf
> +++ b/conf/layer.conf
> @@ -23,5 +23,5 @@ LAYERSERIES_COMPAT_cip-core = "next"
>  LAYERDIR_cip-core = "${LAYERDIR}"
>  LAYERDIR_cip-core[vardepvalue] = "isar-cip-core"
>  
> -IMAGE_CLASSES += "squashfs verity swupdate"
> +IMAGE_CLASSES += "squashfs verity swupdate delta-update"
>  
> diff --git a/kas/opt/swupdate.yml b/kas/opt/swupdate.yml
> index ef61e4e..81dbe95 100644
> --- a/kas/opt/swupdate.yml
> +++ b/kas/opt/swupdate.yml
> @@ -30,3 +30,9 @@ local_conf_header:
>      ABROOTFS_PART_UUID_B ?= "fedcba98-7654-3210-cafe-5e0710000002"
>      PREFERRED_PROVIDER_swupdate-certificates-key ??= "swupdate-
> certificates-key-snakeoil"
>      PREFERRED_PROVIDER_swupdate-certificates ??= "swupdate-
> certificates-snakeoil"
> +    # delta update specific variables"
> +    IMAGE_FSTYPES:append = " delta_update"
> +    DELTA_UPDATE_TYPE = "rdiff"
> +    DELTA_RDIFF_REF_IMAGE = "${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}"
> +    DELTA_ZCK_URL = ""
> +
Adithya Balakumar April 16, 2024, 4:32 a.m. UTC | #2 
-----Original Message-----
From: MOESSBAUER, Felix <felix.moessbauer@siemens.com> 
Sent: Tuesday, April 16, 2024 9:42 AM
To: cip-dev@lists.cip-project.org; balakumar adithya(ＴＳＩＰ TEUR) <Adithya.Balakumar@toshiba-tsip.com>; Kiszka, Jan <jan.kiszka@siemens.com>
Cc: kunijadar shivanand(ＴＳＩＰ TMIEC ODG Porting) <Shivanand.Kunijadar@toshiba-tsip.com>; quirin.gylstorff@siemens.com; dinesh kumar(ＴＳＩＰ TMIEC ODG Porting) <dinesh.kumar@toshiba-tsip.com>; ashrith sai(ＴＳＩＰ) <Sai.Sathujoda@toshiba-tsip.com>; hayashi kazuhiro(林 和宏 ＤＭＥ ○ＤＩＧ□ＭＰＳ○ＭＰ４) <kazuhiro3.hayashi@toshiba.co.jp>
Subject: Re: [isar-cip-core][PATCH v3 1/3] Add Delta update support with rdiff_image and delta handler

On Mon, 2024-04-15 at 16:16 +0530, Adithya Balakumar wrote:
> swupdate supports delta updates with rdiff_image and delta(zchunk) 
> handler. This change adds support to use either of the handler for 
> creating delta update artifacts. zchunk based updates are supported 
> only for sid.
> 
> DELTA_UPDATE_TYPE, DELTA_RDIFF_REF_IMAGE and DELTA_ZCK_URL variables 
> can be modified based on the update type in the swupdate.yml file.
> 
> Signed-off-by: Adithya Balakumar <Adithya.Balakumar@toshiba-tsip.com>
> ---
>  classes/delta-update.bbclass | 97
> ++++++++++++++++++++++++++++++++++++
>  conf/layer.conf              |  2 +-
>  kas/opt/swupdate.yml         |  6 +++
>  3 files changed, 104 insertions(+), 1 deletion(-)
>  create mode 100644 classes/delta-update.bbclass
> 
> diff --git a/classes/delta-update.bbclass b/classes/delta- 
> update.bbclass new file mode 100644 index 0000000..87bf7ff
> --- /dev/null
> +++ b/classes/delta-update.bbclass
> @@ -0,0 +1,97 @@
> +#
> +# CIP Core, generic profile
> +#
> +# Copyright (c) Toshiba Corporation 2024 # # Authors:
> +#  Adithya Balakumar <adithya.balakumar@toshiba-tsip.com>
> +#
> +# SPDX-License-Identifier: MIT
> +#
> +
> +IMAGER_INSTALL:delta_update .= "zchunk rdiff"

When appending with .=, prepend a space.

> +
> +FILESEXTRAPATHS:append = ":${TOPDIR}/previous-image"

Please always prepend to the filesextrapath to make sure this dir is searched first.

Felix

[Adithya Balakumar]
Hi Felix,

Thanks for the feedback. I will fix both your comments in v4.

Adithya
 
> +do_image_delta_update[cleandirs] +=
> "${WORKDIR}/delta_interim_artifacts"
> +
> +DELTA_UPDATE_TYPE ??= "rdiff"
> +DELTA_RDIFF_REF_IMAGE ??= "${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}"
> +DELTA_ZCK_URL ??= ""
> +DELTA_PREV_IMAGE_PATH ??= "${TOPDIR}/previous-image"
> +
> +def disable_delta_update_tasks (d):
> +    d.appendVarFlag("do_image_delta_update", "noexec", "1")
> +    d.setVar("DELTA_UPDATE_TYPE", "")
> +
> +def delta_update_prereq_check (d):
> +    import os
> +    if d.getVar("DELTA_UPDATE_TYPE") == "rdiff":
> +        path = d.getVar("DELTA_PREV_IMAGE_PATH") + "/" +
> d.getVar("DELTA_RDIFF_REF_IMAGE")
> +        if not os.path.isfile(path):
> +            disable_delta_update_tasks(d)
> +        else:
> +            return "file://" + d.getVar("DELTA_RDIFF_REF_IMAGE")
> +    elif d.getVar("DELTA_UPDATE_TYPE") == "zchunk":
> +        if d.getVar("BASE_DISTRO_CODENAME") != "sid":
> +            disable_delta_update_tasks(d)
> +    else:
> +        disable_delta_update_tasks(d)
> +    return ""
> +
> +SRC_URI += "${@delta_update_prereq_check(d)}"
> +
> +create_rdiff_delta_artifact() {
> +    if [ -z "${DELTA_RDIFF_REF_IMAGE}" ]; then
> +        bbfatal "You must set DELTA_RDIFF_REF_IMAGE and provide the
> required files as artifacts to this recipe"
> +    fi
> +
> +    rm -f ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta
> +    # create signature file with rdiff
> +    ${SUDO_CHROOT} /usr/bin/rdiff signature
> ${WORKDIR}/${DELTA_RDIFF_REF_IMAGE} \
> +        ${WORKDIR}/delta_interim_artifacts/old-image-rootfs.sig
> +
> +    # create delta file with the signature file
> +    ${SUDO_CHROOT} /usr/bin/rdiff delta
> ${WORKDIR}/delta_interim_artifacts/old-image-rootfs.sig \
> +        ${PP_DEPLOY}/${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}
> ${PP_DEPLOY}/${IMAGE_FULLNAME}.delta
> +
> +    DELTA_ARTIFACT_SWU=${IMAGE_FULLNAME}.delta
> +
> +    # create a symbolic link as IMAGE_CMD expects a *.delta_update
> file in deploy image directory
> +    ln -sf ${DELTA_ARTIFACT_SWU}
> ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta_update
> +}
> +
> +create_zchunk_delta_artifact() {
> +    # Create .zck file
> +    ${SUDO_CHROOT} /bin/zck \
> +        --output ${PP_DEPLOY}/${IMAGE_FULLNAME}.zck \
> +        -u --chunk-hash-type sha256 \
> +        ${PP_DEPLOY}/${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}
> +
> +    # Calculate size of zck header
> +    HSIZE="$(${SUDO_CHROOT} /bin/zck_read_header -v
> ${PP_DEPLOY}/${IMAGE_FULLNAME}.zck | grep "Header size" | cut -d ':'
> -f 2)"
> +
> +    # Extract the zck header
> +    ${SUDO_CHROOT} /bin/dd if="${PP_DEPLOY}/${IMAGE_FULLNAME}".zck
> of="${PP_DEPLOY}/${IMAGE_FULLNAME}".zck.header bs=1 count="$HSIZE"
> status=none
> +
> +    DELTA_ARTIFACT_SWU=${IMAGE_FULLNAME}.zck.header
> +
> +    # create a symbolic link as IMAGE_CMD expects a *.delta_update
> file in deploy image directory
> +    ln -sf ${DELTA_ARTIFACT_SWU}
> ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta_update
> +}
> +
> +do_image_delta_update[depends] += "${PN}:do_transform_template"
> +IMAGE_CMD:delta_update() {
> +    case "${DELTA_UPDATE_TYPE}" in
> +    "rdiff")
> +        create_rdiff_delta_artifact
> +        ;;
> +    "zchunk")
> +        create_zchunk_delta_artifact
> +        ;;
> +    *)
> +        bbfatal "You must set a valid DELTA_UPDATE_TYPE
> (rdiff/zchunk)"
> +        ;;
> +    esac
> +}
> +
> +addtask do_image_delta_update before do_image_swu after do_image_wic
> diff --git a/conf/layer.conf b/conf/layer.conf index 6198e1b..c652a61 
> 100644
> --- a/conf/layer.conf
> +++ b/conf/layer.conf
> @@ -23,5 +23,5 @@ LAYERSERIES_COMPAT_cip-core = "next"
>  LAYERDIR_cip-core = "${LAYERDIR}"
>  LAYERDIR_cip-core[vardepvalue] = "isar-cip-core"
>  
> -IMAGE_CLASSES += "squashfs verity swupdate"
> +IMAGE_CLASSES += "squashfs verity swupdate delta-update"
>  
> diff --git a/kas/opt/swupdate.yml b/kas/opt/swupdate.yml index 
> ef61e4e..81dbe95 100644
> --- a/kas/opt/swupdate.yml
> +++ b/kas/opt/swupdate.yml
> @@ -30,3 +30,9 @@ local_conf_header:
>      ABROOTFS_PART_UUID_B ?= "fedcba98-7654-3210-cafe-5e0710000002"
>      PREFERRED_PROVIDER_swupdate-certificates-key ??= "swupdate- 
> certificates-key-snakeoil"
>      PREFERRED_PROVIDER_swupdate-certificates ??= "swupdate- 
> certificates-snakeoil"
> +    # delta update specific variables"
> +    IMAGE_FSTYPES:append = " delta_update"
> +    DELTA_UPDATE_TYPE = "rdiff"
> +    DELTA_RDIFF_REF_IMAGE = "${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}"
> +    DELTA_ZCK_URL = ""
> +

--
Siemens AG, Technology
Linux Expert Center
diff mbox series

Patch

diff --git a/classes/delta-update.bbclass b/classes/delta-update.bbclass
new file mode 100644
index 0000000..87bf7ff
--- /dev/null
+++ b/classes/delta-update.bbclass
@@ -0,0 +1,97 @@ 
+#
+# CIP Core, generic profile
+#
+# Copyright (c) Toshiba Corporation 2024
+#
+# Authors:
+#  Adithya Balakumar <adithya.balakumar@toshiba-tsip.com>
+#
+# SPDX-License-Identifier: MIT
+#
+
+IMAGER_INSTALL:delta_update .= "zchunk rdiff"
+
+FILESEXTRAPATHS:append = ":${TOPDIR}/previous-image"
+do_image_delta_update[cleandirs] += "${WORKDIR}/delta_interim_artifacts"
+
+DELTA_UPDATE_TYPE ??= "rdiff"
+DELTA_RDIFF_REF_IMAGE ??= "${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}"
+DELTA_ZCK_URL ??= ""
+DELTA_PREV_IMAGE_PATH ??= "${TOPDIR}/previous-image"
+
+def disable_delta_update_tasks (d):
+    d.appendVarFlag("do_image_delta_update", "noexec", "1")
+    d.setVar("DELTA_UPDATE_TYPE", "")
+
+def delta_update_prereq_check (d):
+    import os
+    if d.getVar("DELTA_UPDATE_TYPE") == "rdiff":
+        path = d.getVar("DELTA_PREV_IMAGE_PATH") + "/" + d.getVar("DELTA_RDIFF_REF_IMAGE")
+        if not os.path.isfile(path):
+            disable_delta_update_tasks(d)
+        else:
+            return "file://" + d.getVar("DELTA_RDIFF_REF_IMAGE")
+    elif d.getVar("DELTA_UPDATE_TYPE") == "zchunk":
+        if d.getVar("BASE_DISTRO_CODENAME") != "sid":
+            disable_delta_update_tasks(d)
+    else:
+        disable_delta_update_tasks(d)
+    return ""
+
+SRC_URI += "${@delta_update_prereq_check(d)}"
+
+create_rdiff_delta_artifact() {
+    if [ -z "${DELTA_RDIFF_REF_IMAGE}" ]; then
+        bbfatal "You must set DELTA_RDIFF_REF_IMAGE and provide the required files as artifacts to this recipe"
+    fi
+
+    rm -f ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta
+    # create signature file with rdiff
+    ${SUDO_CHROOT} /usr/bin/rdiff signature ${WORKDIR}/${DELTA_RDIFF_REF_IMAGE} \
+        ${WORKDIR}/delta_interim_artifacts/old-image-rootfs.sig
+
+    # create delta file with the signature file
+    ${SUDO_CHROOT} /usr/bin/rdiff delta ${WORKDIR}/delta_interim_artifacts/old-image-rootfs.sig \
+        ${PP_DEPLOY}/${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE} ${PP_DEPLOY}/${IMAGE_FULLNAME}.delta
+
+    DELTA_ARTIFACT_SWU=${IMAGE_FULLNAME}.delta
+
+    # create a symbolic link as IMAGE_CMD expects a *.delta_update file in deploy image directory
+    ln -sf ${DELTA_ARTIFACT_SWU} ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta_update
+}
+
+create_zchunk_delta_artifact() {
+    # Create .zck file
+    ${SUDO_CHROOT} /bin/zck \
+        --output ${PP_DEPLOY}/${IMAGE_FULLNAME}.zck \
+        -u --chunk-hash-type sha256 \
+        ${PP_DEPLOY}/${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}
+
+    # Calculate size of zck header
+    HSIZE="$(${SUDO_CHROOT} /bin/zck_read_header -v ${PP_DEPLOY}/${IMAGE_FULLNAME}.zck | grep "Header size" | cut -d ':' -f 2)"
+
+    # Extract the zck header
+    ${SUDO_CHROOT} /bin/dd if="${PP_DEPLOY}/${IMAGE_FULLNAME}".zck of="${PP_DEPLOY}/${IMAGE_FULLNAME}".zck.header bs=1 count="$HSIZE" status=none
+
+    DELTA_ARTIFACT_SWU=${IMAGE_FULLNAME}.zck.header
+
+    # create a symbolic link as IMAGE_CMD expects a *.delta_update file in deploy image directory
+    ln -sf ${DELTA_ARTIFACT_SWU} ${DEPLOY_DIR_IMAGE}/${IMAGE_FULLNAME}.delta_update
+}
+
+do_image_delta_update[depends] += "${PN}:do_transform_template"
+IMAGE_CMD:delta_update() {
+    case "${DELTA_UPDATE_TYPE}" in
+    "rdiff")
+        create_rdiff_delta_artifact
+        ;;
+    "zchunk")
+        create_zchunk_delta_artifact
+        ;;
+    *)
+        bbfatal "You must set a valid DELTA_UPDATE_TYPE (rdiff/zchunk)"
+        ;;
+    esac
+}
+
+addtask do_image_delta_update before do_image_swu after do_image_wic
diff --git a/conf/layer.conf b/conf/layer.conf
index 6198e1b..c652a61 100644
--- a/conf/layer.conf
+++ b/conf/layer.conf
@@ -23,5 +23,5 @@  LAYERSERIES_COMPAT_cip-core = "next"
 LAYERDIR_cip-core = "${LAYERDIR}"
 LAYERDIR_cip-core[vardepvalue] = "isar-cip-core"
 
-IMAGE_CLASSES += "squashfs verity swupdate"
+IMAGE_CLASSES += "squashfs verity swupdate delta-update"
 
diff --git a/kas/opt/swupdate.yml b/kas/opt/swupdate.yml
index ef61e4e..81dbe95 100644
--- a/kas/opt/swupdate.yml
+++ b/kas/opt/swupdate.yml
@@ -30,3 +30,9 @@  local_conf_header:
     ABROOTFS_PART_UUID_B ?= "fedcba98-7654-3210-cafe-5e0710000002"
     PREFERRED_PROVIDER_swupdate-certificates-key ??= "swupdate-certificates-key-snakeoil"
     PREFERRED_PROVIDER_swupdate-certificates ??= "swupdate-certificates-snakeoil"
+    # delta update specific variables"
+    IMAGE_FSTYPES:append = " delta_update"
+    DELTA_UPDATE_TYPE = "rdiff"
+    DELTA_RDIFF_REF_IMAGE = "${IMAGE_FULLNAME}.${SWU_ROOTFS_TYPE}"
+    DELTA_ZCK_URL = ""
+