[PATCH 1/1] improve_kerne_cve_report: Add a bbclass support

[ValentinBoudevin <valentin.boudevin@gmail.com>]

The script improve_kernel_cve_report.py doesn't have a bbclass.
It can be usefull to have one to generate improved cve-check files at
every run.

This new class can be used to generate a new file in tmp/deploy/images
with a .scouted.json in addition to the existing .json cve-check file.

The new .scouted.json is based on the cve-check file and the SBOM (SPDX3
mandatory) to generate this improved cve-check file with extra entries
found by the script improve_kernel_cve_report.py.

It only requires an inherit on an image recipe (e.g. "inherit
improve_kernel_cve_report" in core-image-minimal).

It can be add to core-image-minimal in a second step if revelant.

Signed-off-by: Valentin Boudevin <valentin.boudevin@gmail.com>
---
 .../classes/improve_kernel_cve_report.bbclass | 71 +++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 meta/classes/improve_kernel_cve_report.bbclass

diff --git a/meta/classes/improve_kernel_cve_report.bbclass b/meta/classes/improve_kernel_cve_report.bbclass
new file mode 100644
index 0000000000..5c496252b4
--- /dev/null
+++ b/meta/classes/improve_kernel_cve_report.bbclass
@@ -0,0 +1,71 @@
+python do_clean:append() {
+    import os, glob
+    if bb.utils.contains('INHERIT', 'create-spdx-2.2', 'false', 'true', d):
+        deploy_dir = d.expand('${DEPLOY_DIR_IMAGE}')
+        for f in glob.glob(os.path.join(deploy_dir, '*scouted.json')):
+            bb.note("Removing " + f)
+            os.remove(f)
+}
+
+python do_clone_kernel_cve() {
+    import subprocess
+    import shutil, os
+    check_spdx = d.getVar("INHERIT")
+    rootdir = os.path.join(d.getVar("WORKDIR"), "vulns")
+    # Check if the feature is enabled and if SPDX 2.2 is not used
+    if "create-spdx-2.2" not in check_spdx:
+        d.setVar("SRC_URI", "git://git.kernel.org/pub/scm/linux/security/vulns.git;branch=master;protocol=https")
+        d.setVar("SRCREV", "${AUTOREV}")
+        src_uri = (d.getVar('SRC_URI') or "").split()
+        # Fetch the kernel vulnerabilities sources
+        fetcher = bb.fetch2.Fetch(src_uri, d)
+        fetcher.download()
+        # Unpack into the standard work directory
+        fetcher.unpack(rootdir)
+        # Remove the folder ${PN} set by unpack
+        subdirs = [d for d in os.listdir(rootdir) if os.path.isdir(os.path.join(rootdir, d))]
+        if len(subdirs) == 1:
+            srcdir = os.path.join(rootdir, subdirs[0])
+            for f in os.listdir(srcdir):
+                shutil.move(os.path.join(srcdir, f), rootdir)
+            shutil.rmtree(srcdir)
+        bb.note("Vulnerabilities repo unpacked into: %s" % rootdir)
+    elif "create-spdx-2.2" in check_spdx:
+        bb.warn(f"improve_kernel_cve_report: Extra Kernel CVEs Scouting is desactivate because incompatible with SPDX 2.2.")
+}
+do_clone_kernel_cve[network] = "1"
+do_clone_kernel_cve[nostamp] = "1"
+do_clone_kernel_cve[doc] = "Clone the latest kernel vulnerabilities from https://git.kernel.org/pub/scm/linux/security/vulns.git"
+addtask clone_kernel_cve after
+
+do_scout_extra_kernel_vulns() {
+    spdx_file="${SPDXIMAGEDEPLOYDIR}/${IMAGE_LINK_NAME}.spdx.json"
+    original_cve_check_file="${DEPLOY_DIR_IMAGE}/${IMAGE_LINK_NAME}.json"
+    new_cve_report_file="${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.scouted.json"
+    improve_kernel_cve_script="${COREBASE}/scripts/contrib/improve_kernel_cve_report.py"
+
+    if ${@bb.utils.contains('INHERIT', 'create-spdx-2.2', 'true', 'false', d)}; then
+        bbwarn "improve_kernel_cve_report: Skipping extra kernel vulnerabilities scouting because incompatible with SPDX 2."
+        return 0
+    elif [ ! -f "${spdx_file}" ]; then
+        bbwarn "improve_kernel_cve_report: SPDX file not found: ${spdx_file}. Skipping extra kernel vulnerabilities scoutings."
+        return 0
+    elif [ ! -f "${original_cve_check_file}" ]; then
+        bbwarn "improve_kernel_cve_report: CVE_CHECK file not found: ${original_cve_check_file}. Skipping extra kernel vulnerabilities scouting."
+        return 0
+    fi
+
+    #Launch the new script to improve the cve report
+    python3 "${improve_kernel_cve_script}" \
+        --spdx "${spdx_file}" \
+        --old-cve-report "${original_cve_check_file}" \
+        --new-cve-report "${new_cve_report_file}" \
+        --datadir "${WORKDIR}/vulns"
+    bbplain "Improve CVE report with extra kernel cves: ${new_cve_report_file}"
+
+    #Create a symlink as every other JSON file in tmp/deploy/images
+    ln -sf ${DEPLOY_DIR_IMAGE}/${IMAGE_NAME}.scouted.json ${DEPLOY_DIR_IMAGE}/${IMAGE_BASENAME}${IMAGE_MACHINE_SUFFIX}${IMAGE_NAME_SUFFIX}.scouted.json
+}
+do_scout_extra_kernel_vulns[nostamp] = "1"
+do_scout_extra_kernel_vulns[doc] = "Scout extra kernel vulnerabilities and create a new enhanced version of the cve_check file in the deploy directory"
+addtask scout_extra_kernel_vulns after do_create_image_sbom_spdx before do_build
\ No newline at end of file