Match digest

eventlog.py

@@ -285,3 +285,45 @@ def validate (self):
         for evt in self:
             if not evt.validate(): return False
         return True
+
+
+def get_digests (evlog: EventLog, evtype: str, **kwargs) -> list:
+
+    assert evtype in Event.__members__
+
+    algid=kwargs.get('hash_algid',None)
+    if algid:
+        assert algid in EfiEventDigest.hashalgmap
+
+    pcr=kwargs.get('pcr_index',None)
+
+    digest_list=[]
+
+    for ev in evlog:
+        if Event(ev.evtype).name == evtype:
+            if pcr:
+                if ev.evpcr != pcr: continue
+            if algid:
+                digest=ev.digests[algid].toJson()
+                digest_list.append(digest['Digest'])
+            else:
+                for v in ev.digests.values():
+                    digest_list.append(v.toJson())
+
+    return digest_list
+
+def match_digest (evlog: EventLog, evtype: str, algid: int, digest: str, **kwargs) -> bool:
+
+    assert evtype in Event.__members__
+    assert algid in EfiEventDigest.hashalgmap
+
+    pcr=kwargs.get('pcr_index',None)
+
+    for ev in evlog:
+        if pcr:
+            if ev.evpcr != pcr: continue
+        if algid:
+            dg=ev.digests[algid].toJson()
+            if dg['Digest'] == digest:
+                return True
+    return False

match_digest.py

@@ -0,0 +1,76 @@
+#!/usr/bin/env python3
+
+import eventlog
+import argparse
+
+def parser_main():
+    parser = argparse.ArgumentParser(
+        description="List/Match the digest[s]"
+    )
+    parser.add_argument(
+        "-f",
+        "--file",
+        help="measured boot log binary file",
+    )
+    parser.add_argument(
+        "-d",
+        "--digest",
+        help="digest value",
+    )
+    parser.add_argument(
+        "-e",
+        "--event",
+        help="event type",
+    )
+    parser.add_argument(
+        "-a",
+        "--algid",
+        default="11",
+        help="algorithm id",
+    ) 
+    parser.add_argument(
+        "-p",
+        "--pcr",
+        help="pcr index",
+    ) 
+    return parser
+
+def main():
+    p = parser_main()
+    args = p.parse_args()
+
+    assert (args.file),"file is required"
+    assert (args.event),"event type is required"
+
+    with open (args.file, 'rb') as f:
+        buffer = f.read()
+
+    if args.event not in eventlog.Event.__members__:
+        print('Invalid event type')
+        return
+
+    algid = int(args.algid)
+    if algid not in eventlog.EfiEventDigest.hashalgmap:
+        print ('Invalid hash algorithm id.')
+        return
+
+    log=eventlog.EventLog(buffer, len(buffer))
+
+    if not args.digest:
+        if args.pcr:
+            dg_list = eventlog.get_digests(log, args.event, hash_algid=algid, pcr_index=int(args.pcr))
+        else:
+            dg_list = eventlog.get_digests(log, args.event, hash_algid=algid)
+        print(dg_list) 
+    else:
+        if args.pcr:
+            matched = eventlog.match_digest(log, args.event, algid, args.digest, pcr_index=int(args.pcr))
+        else:
+            matched = eventlog.match_digest(log, args.event, algid, args.digest, algid)
+        if matched:
+            print('Digest matched!')
+        else:
+            print('Digest does not match!')
+
+if __name__ == "__main__":
+    main()