Improve reporting of empty CVE database (#918) (#928)

Author: anthonyharrison

cve_bin_tool/cli.py

@@ -32,6 +32,7 @@
     InsufficientArgs,
     EmptyCache,
     ErrorMode,
+    CVEDataMissing,
 )
 from .input_engine import InputEngine, TriageData
 from .log import LOGGER
@@ -254,6 +255,11 @@ def main(argv=None):
             with ErrorHandler(mode=error_mode, logger=LOGGER):
                 raise EmptyCache(cvedb_orig.cachedir)
 
+    # CVE Database validation
+    if not cvedb_orig.check_cve_entries():
+        with ErrorHandler(mode=error_mode, logger=LOGGER):
+            raise CVEDataMissing("No data in CVE Database")
+
     # Input validation
     if not args["directory"] and not args["input_file"]:
         parser.print_usage()

cve_bin_tool/cvedb.py

@@ -266,6 +266,18 @@ def latest_schema(self, cursor):
                 schema_latest = True
         return schema_latest
 
+    def check_cve_entries(self):
+        """ Report if database has some CVE entries """
+        self.db_open()
+        cursor = self.connection.cursor()
+        cve_entries_check = "SELECT COUNT(*) FROM cve_severity"
+        cursor.execute(cve_entries_check)
+        # Find number of entries
+        cve_entries = cursor.fetchone()[0]
+        self.LOGGER.info(f"There are {cve_entries} CVE entries in the database")
+        self.db_close()
+        return cve_entries > 0
+
     def init_database(self):
         """ Initialize db tables used for storing cve/version data """
         self.db_open()

cve_bin_tool/error_handler.py

@@ -44,6 +44,12 @@ class CVEDataForCurlVersionNotInCache(Exception):
     """
 
 
+class CVEDataMissing(Exception):
+    """
+    Raised when no CVE data is present in the database.
+    """
+
+
 class AttemptedToWriteOutsideCachedir(Exception):
     """
     Raised if we attempted to write to a file that would have been outside the
@@ -145,4 +151,5 @@ def __exit__(self, exc_type, exc_val, exc_tb):
     ExtractionFailed: -12,
     UnknownArchiveType: -13,
     UnknownConfigType: -14,
+    CVEDataMissing: -15,
 }