From b8ae26aabe825c1bc8d84fd7e0ee197695f1dee7 Mon Sep 17 00:00:00 2001 From: Marta Rybczynska Date: Wed, 29 Mar 2023 12:02:56 +0200 Subject: cve-update-nvd2-native: new CVE database fetcher Add new fetcher for the NVD database using the 2.0 API [1]. The implementation changes as little as possible, keeping the current database format (but using a different database file for the transition period), with a notable exception of not using the META table. Minor changes that could be visible: - the database starts in 1999 instead of 2002 - the complete fetch is longer (30 minutes typically) [1] https://nvd.nist.gov/developers/vulnerabilities Signed-off-by: Marta Rybczynska Signed-off-by: Alexandre Belloni (cherry picked from commit fb62c4c3dbca4e58f7ce6cf29d4b630a06411a97) Signed-off-by: Steve Sakoman --- meta/recipes-core/meta/cve-update-nvd2-native.bb | 333 +++++++++++++++++++++++ 1 file changed, 333 insertions(+) create mode 100644 meta/recipes-core/meta/cve-update-nvd2-native.bb (limited to 'meta/recipes-core') diff --git a/meta/recipes-core/meta/cve-update-nvd2-native.bb b/meta/recipes-core/meta/cve-update-nvd2-native.bb new file mode 100644 index 0000000000..1c14481c21 --- /dev/null +++ b/meta/recipes-core/meta/cve-update-nvd2-native.bb @@ -0,0 +1,333 @@ +SUMMARY = "Updates the NVD CVE database" +LICENSE = "MIT" + +# Important note: +# This product uses the NVD API but is not endorsed or certified by the NVD. + +INHIBIT_DEFAULT_DEPS = "1" + +inherit native + +deltask do_unpack +deltask do_patch +deltask do_configure +deltask do_compile +deltask do_install +deltask do_populate_sysroot + +NVDCVE_URL ?= "https://services.nvd.nist.gov/rest/json/cves/2.0" + +# CVE database update interval, in seconds. By default: once a day (24*60*60). +# Use 0 to force the update +# Use a negative value to skip the update +CVE_DB_UPDATE_INTERVAL ?= "86400" + +# Timeout for blocking socket operations, such as the connection attempt. +CVE_SOCKET_TIMEOUT ?= "60" + +CVE_DB_TEMP_FILE ?= "${CVE_CHECK_DB_DIR}/temp_nvdcve_2.db" + +CVE_CHECK_DB_FILE ?= "${CVE_CHECK_DB_DIR}/nvdcve_2.db" + +python () { + if not bb.data.inherits_class("cve-check", d): + raise bb.parse.SkipRecipe("Skip recipe when cve-check class is not loaded.") +} + +python do_fetch() { + """ + Update NVD database with API 2.0 + """ + import bb.utils + import bb.progress + import shutil + + bb.utils.export_proxies(d) + + db_file = d.getVar("CVE_CHECK_DB_FILE") + db_dir = os.path.dirname(db_file) + db_tmp_file = d.getVar("CVE_DB_TEMP_FILE") + + cleanup_db_download(db_file, db_tmp_file) + # By default let's update the whole database (since time 0) + database_time = 0 + + # The NVD database changes once a day, so no need to update more frequently + # Allow the user to force-update + try: + import time + update_interval = int(d.getVar("CVE_DB_UPDATE_INTERVAL")) + if update_interval < 0: + bb.note("CVE database update skipped") + return + if time.time() - os.path.getmtime(db_file) < update_interval: + bb.note("CVE database recently updated, skipping") + return + database_time = os.path.getmtime(db_file) + + except OSError: + pass + + bb.utils.mkdirhier(db_dir) + if os.path.exists(db_file): + shutil.copy2(db_file, db_tmp_file) + + if update_db_file(db_tmp_file, d, database_time) == True: + # Update downloaded correctly, can swap files + shutil.move(db_tmp_file, db_file) + else: + # Update failed, do not modify the database + bb.warn("CVE database update failed") + os.remove(db_tmp_file) +} + +do_fetch[lockfiles] += "${CVE_CHECK_DB_FILE_LOCK}" +do_fetch[file-checksums] = "" +do_fetch[vardeps] = "" + +def cleanup_db_download(db_file, db_tmp_file): + """ + Cleanup the download space from possible failed downloads + """ + + # Clean up the updates done on the main file + # Remove it only if a journal file exists - it means a complete re-download + if os.path.exists("{0}-journal".format(db_file)): + # If a journal is present the last update might have been interrupted. In that case, + # just wipe any leftovers and force the DB to be recreated. + os.remove("{0}-journal".format(db_file)) + + if os.path.exists(db_file): + os.remove(db_file) + + # Clean-up the temporary file downloads, we can remove both journal + # and the temporary database + if os.path.exists("{0}-journal".format(db_tmp_file)): + # If a journal is present the last update might have been interrupted. In that case, + # just wipe any leftovers and force the DB to be recreated. + os.remove("{0}-journal".format(db_tmp_file)) + + if os.path.exists(db_tmp_file): + os.remove(db_tmp_file) + +def nvd_request_next(url, api_key, args): + """ + Request next part of the NVD dabase + """ + + import urllib.request + import urllib.parse + import gzip + + headers = {} + if api_key: + headers['apiKey'] = api_key + + data = urllib.parse.urlencode(args) + + full_request = url + '?' + data + + for attempt in range(3): + try: + r = urllib.request.urlopen(full_request) + + if (r.headers['content-encoding'] == 'gzip'): + buf = r.read() + raw_data = gzip.decompress(buf) + else: + raw_data = r.read().decode("utf-8") + + r.close() + + except UnicodeDecodeError: + # Received garbage, retry + bb.debug(2, "CVE database: received malformed data, retrying (request: %s)" %(full_request)) + pass + except http.client.IncompleteRead: + # Read incomplete, let's try again + bb.debug(2, "CVE database: received incomplete data, retrying (request: %s)" %(full_request)) + pass + else: + return raw_data + else: + # We failed at all attempts + return None + +def update_db_file(db_tmp_file, d, database_time): + """ + Update the given database file + """ + import bb.utils, bb.progress + import datetime + import sqlite3 + import json + + # Connect to database + conn = sqlite3.connect(db_tmp_file) + initialize_db(conn) + + req_args = {'startIndex' : 0} + + # The maximum range for time is 120 days + # Force a complete update if our range is longer + if (database_time != 0): + database_date = datetime.datetime.combine(datetime.date.fromtimestamp(database_time), datetime.time()) + today_date = datetime.datetime.combine(datetime.date.today(), datetime.time()) + delta = today_date - database_date + if delta.days < 120: + bb.debug(2, "CVE database: performing partial update") + req_args['lastModStartDate'] = database_date.isoformat() + req_args['lastModEndDate'] = today_date.isoformat() + else: + bb.note("CVE database: file too old, forcing a full update") + + with bb.progress.ProgressHandler(d) as ph, open(os.path.join(d.getVar("TMPDIR"), 'cve_check'), 'a') as cve_f: + + bb.debug(2, "Updating entries") + index = 0 + url = d.getVar("NVDCVE_URL") + while True: + req_args['startIndex'] = index + raw_data = nvd_request_next(url, None, req_args) + if raw_data is None: + # We haven't managed to download data + return False + + data = json.loads(raw_data) + + index = data["startIndex"] + total = data["totalResults"] + per_page = data["resultsPerPage"] + + for cve in data["vulnerabilities"]: + update_db(conn, cve) + + index += per_page + ph.update((float(index) / (total+1)) * 100) + if index >= total: + break + + # Recommended by NVD + time.sleep(6) + + # Update success, set the date to cve_check file. + cve_f.write('CVE database update : %s\n\n' % datetime.date.today()) + + conn.commit() + conn.close() + return True + +def initialize_db(conn): + with conn: + c = conn.cursor() + + c.execute("CREATE TABLE IF NOT EXISTS META (YEAR INTEGER UNIQUE, DATE TEXT)") + + c.execute("CREATE TABLE IF NOT EXISTS NVD (ID TEXT UNIQUE, SUMMARY TEXT, \ + SCOREV2 TEXT, SCOREV3 TEXT, MODIFIED INTEGER, VECTOR TEXT)") + + c.execute("CREATE TABLE IF NOT EXISTS PRODUCTS (ID TEXT, \ + VENDOR TEXT, PRODUCT TEXT, VERSION_START TEXT, OPERATOR_START TEXT, \ + VERSION_END TEXT, OPERATOR_END TEXT)") + c.execute("CREATE INDEX IF NOT EXISTS PRODUCT_ID_IDX on PRODUCTS(ID);") + + c.close() + +def parse_node_and_insert(conn, node, cveId): + + def cpe_generator(): + for cpe in node.get('cpeMatch', ()): + if not cpe['vulnerable']: + return + cpe23 = cpe.get('criteria') + if not cpe23: + return + cpe23 = cpe23.split(':') + if len(cpe23) < 6: + return + vendor = cpe23[3] + product = cpe23[4] + version = cpe23[5] + + if cpe23[6] == '*' or cpe23[6] == '-': + version_suffix = "" + else: + version_suffix = "_" + cpe23[6] + + if version != '*' and version != '-': + # Version is defined, this is a '=' match + yield [cveId, vendor, product, version + version_suffix, '=', '', ''] + elif version == '-': + # no version information is available + yield [cveId, vendor, product, version, '', '', ''] + else: + # Parse start version, end version and operators + op_start = '' + op_end = '' + v_start = '' + v_end = '' + + if 'versionStartIncluding' in cpe: + op_start = '>=' + v_start = cpe['versionStartIncluding'] + + if 'versionStartExcluding' in cpe: + op_start = '>' + v_start = cpe['versionStartExcluding'] + + if 'versionEndIncluding' in cpe: + op_end = '<=' + v_end = cpe['versionEndIncluding'] + + if 'versionEndExcluding' in cpe: + op_end = '<' + v_end = cpe['versionEndExcluding'] + + if op_start or op_end or v_start or v_end: + yield [cveId, vendor, product, v_start, op_start, v_end, op_end] + else: + # This is no version information, expressed differently. + # Save processing by representing as -. + yield [cveId, vendor, product, '-', '', '', ''] + + conn.executemany("insert into PRODUCTS values (?, ?, ?, ?, ?, ?, ?)", cpe_generator()).close() + +def update_db(conn, elt): + """ + Update a single entry in the on-disk database + """ + + accessVector = None + cveId = elt['cve']['id'] + if elt['cve']['vulnStatus'] == "Rejected": + return + cveDesc = "" + for desc in elt['cve']['descriptions']: + if desc['lang'] == 'en': + cveDesc = desc['value'] + date = elt['cve']['lastModified'] + try: + accessVector = elt['cve']['metrics']['cvssMetricV2'][0]['cvssData']['accessVector'] + cvssv2 = elt['cve']['metrics']['cvssMetricV2'][0]['cvssData']['baseScore'] + except KeyError: + cvssv2 = 0.0 + try: + accessVector = accessVector or elt['impact']['baseMetricV3']['cvssV3']['attackVector'] + cvssv3 = elt['impact']['baseMetricV3']['cvssV3']['baseScore'] + except KeyError: + accessVector = accessVector or "UNKNOWN" + cvssv3 = 0.0 + + conn.execute("insert or replace into NVD values (?, ?, ?, ?, ?, ?)", + [cveId, cveDesc, cvssv2, cvssv3, date, accessVector]).close() + + try: + configurations = elt['cve']['configurations'][0]['nodes'] + for config in configurations: + parse_node_and_insert(conn, config, cveId) + except KeyError: + bb.debug(2, "Entry without a configuration") + +do_fetch[nostamp] = "1" + +EXCLUDE_FROM_WORLD = "1" -- cgit 1.2.3-korg