[PATCH 1/8] g10/decrypt-data: use fill_buffer in more places

[Jussi Kivilinna]

Hello,

On 29.10.2018 15.45, Werner Koch wrote:
> Hi!
> 
> All patches look fine to me.  After applying we should however run
> extensive tests against another implementation to see whether we have
> any breakage.  With the current code this has been with the help of
> the www.rnpgp.com folks.

Should I push this patch set to new branch in gnupg repo?

I've also looked at disabling extra hash contexts when decrypting
non-signed files. Could those contexts be disabled when any AEAD or
MDC encrypted packet is seen? Such patch would look something this:

diff --git a/g10/mainproc.c b/g10/mainproc.c
index 5b7bc9555..4309b52ac 100644
--- a/g10/mainproc.c
+++ b/g10/mainproc.c
@@ -91,6 +91,8 @@ struct mainproc_context
                                      has been seen. */
     unsigned int data:1;          /* Any data packet seen */
     unsigned int uncompress_failed:1;
+    unsigned int seen_encrypted_mdc:1; /* Any PKT_ENCRYPTED_MDC packet seen */
+    unsigned int seen_encrypted_aead:1; /* Any PKT_ENCRYPTED_AEAD packet seen */
   } any;
 };
 
@@ -536,6 +538,9 @@ proc_encrypted (CTX c, PACKET *pkt)
   int result = 0;
   int early_plaintext = literals_seen;
 
+  c->any.seen_encrypted_mdc |= (pkt->pkttype == PKT_ENCRYPTED_MDC);
+  c->any.seen_encrypted_aead |= (pkt->pkttype == PKT_ENCRYPTED_AEAD);
+
   if (early_plaintext)
     {
       log_info (_("WARNING: multiple plaintexts seen\n"));

@@ -874,7 +878,8 @@ proc_plaintext( CTX c, PACKET *pkt )
         }
     }
 
-  if (!any && !opt.skip_verify)
+  if (!any && !opt.skip_verify && !c->any.seen_encrypted_mdc &&
+      !c->any.seen_encrypted_aead)
     {
       /* This is for the old GPG LITERAL+SIG case.  It's not legal
          according to 2440, so hopefully it won't come up that often.


-Jussi