From c3cd98d1523222327ee6ffb274aa6447bffad074 Mon Sep 17 00:00:00 2001
From: Mike McLean <mikem@redhat.com>
Date: Mar 14 2023 10:08:16 +0000
Subject: only pad header lengths for signature headers


Based on a workaround by puiterwijk
https://github.com/fedora-iot/rpm-head-signing/pull/61/files

---

diff --git a/koji/__init__.py b/koji/__init__.py
index d0fece3..64716f4 100644
--- a/koji/__init__.py
+++ b/koji/__init__.py
@@ -618,11 +618,12 @@ def find_rpm_sighdr(path):
 
     # The lead is a fixed sized section (96 bytes) that is mostly obsolete
     sig_start = 96
-    sigsize = rpm_hdr_size(path, sig_start)
+    sigsize = rpm_hdr_size(path, sig_start, pad=True)
+    # "As of RPM 2.1 ... the Signature section is padded to a multiple of 8 bytes"
     return (sig_start, sigsize)
 
 
-def rpm_hdr_size(f, ofs=None):
+def rpm_hdr_size(f, ofs=None, pad=False):
     """Returns the length (in bytes) of the rpm header
 
     f = filename or file object
@@ -652,8 +653,9 @@ def rpm_hdr_size(f, ofs=None):
     # this is what the section data says the size should be
     hdrsize = 8 + 16 * il + dl
 
-    # hdrsize rounded up to nearest 8 bytes
-    hdrsize = hdrsize + (8 - (hdrsize % 8)) % 8
+    if pad:
+        # signature headers are padded to a multiple of 8 bytes
+        hdrsize = hdrsize + (8 - (hdrsize % 8)) % 8
 
     # add eight bytes for section header
     hdrsize = hdrsize + 8