From 362c4401979f896de1e69a3e18d33954953912cc Mon Sep 17 00:00:00 2001
Message-Id: <362c4401979f896de1e69a3e18d33954953912cc.1554983588.git.pmatilai@redhat.com>
From: Panu Matilainen <pmatilai@redhat.com>
Date: Tue, 11 Dec 2018 13:21:47 +0200
Subject: [PATCH] Only read through payload on verify if actually needed

If none of our verify items ranges over the payload, then why bother?

To do this, add an internal rpmvs API to get it's range, and use
that to decide whether trip over the payload is needed or not.
In addition, the payload digest tag needs to be grabbed outside of the
condition to avoid depending on other values. The details including
RPMVSF_NEEDPAYLOAD will be handled internally to rpmvs which makes it
actually nicer code-wise too.
---
 lib/rpmchecksig.c |  8 ++++----
 lib/rpmvs.c       | 12 ++++++++++++
 lib/rpmvs.h       |  3 +++
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/lib/rpmchecksig.c b/lib/rpmchecksig.c
index 1ba72a45e..810f7153d 100644
--- a/lib/rpmchecksig.c
+++ b/lib/rpmchecksig.c
@@ -187,11 +187,11 @@ rpmRC rpmpkgRead(struct rpmvs_s *vs, FD_t fd,
     /* Finalize header range */
     rpmvsFiniRange(vs, RPMSIG_HEADER);
 
-    /* Unless disabled, read the payload, generating digest(s) on the fly. */
-    if (!(rpmvsFlags(vs) & RPMVSF_NEEDPAYLOAD)) {
-	/* Fish interesting tags from the main header. This is a bit hacky... */
-	rpmvsAppendTag(vs, blob, RPMTAG_PAYLOADDIGEST);
+    /* Fish interesting tags from the main header. This is a bit hacky... */
+    rpmvsAppendTag(vs, blob, RPMTAG_PAYLOADDIGEST);
 
+    /* If needed and not explicitly disabled, read the payload as well. */
+    if (rpmvsRange(vs) & RPMSIG_PAYLOAD) {
 	/* Initialize digests ranging over the payload only */
 	rpmvsInitRange(vs, RPMSIG_PAYLOAD);
 
diff --git a/lib/rpmvs.c b/lib/rpmvs.c
index 622e48011..0d475af86 100644
--- a/lib/rpmvs.c
+++ b/lib/rpmvs.c
@@ -396,6 +396,18 @@ void rpmvsFiniRange(struct rpmvs_s *sis, int range)
     }
 }
 
+int rpmvsRange(struct rpmvs_s *vs)
+{
+    int range = 0;
+    for (int i = 0; i < vs->nsigs; i++) {
+	if (rpmsinfoDisabled(&vs->sigs[i], vs->vsflags))
+	    continue;
+	range |= vs->sigs[i].range;
+    }
+
+    return range;
+}
+
 static int sinfoCmp(const void *a, const void *b)
 {
     const struct rpmsinfo_s *sa = a;
diff --git a/lib/rpmvs.h b/lib/rpmvs.h
index b27d9a612..a836d5c94 100644
--- a/lib/rpmvs.h
+++ b/lib/rpmvs.h
@@ -75,6 +75,9 @@ void rpmvsInitRange(struct rpmvs_s *sis, int range);
 RPM_GNUC_INTERNAL
 void rpmvsFiniRange(struct rpmvs_s *sis, int range);
 
+RPM_GNUC_INTERNAL
+int rpmvsRange(struct rpmvs_s *vs);
+
 RPM_GNUC_INTERNAL
 int rpmvsVerify(struct rpmvs_s *sis, int type,
                        rpmsinfoCb cb, void *cbdata);
-- 
2.20.1