rpm2cpio.sh: Check for header magic

This make is much less likely to mistake a file as an RPM and will catch errors in header size calculation.
rpm-software-management · Jul 13, 2022 · ba31a14 · ba31a14
1 parent 4420c78
commit ba31a14
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/scripts/rpm2cpio.sh b/scripts/rpm2cpio.sh
@@ -15,6 +15,12 @@ _dd() {
 }
 
 calcsize() {
+
+ case "$(_dd $1 bs=4 count=1 | tr -d '\0')" in
+ "$(printf '\216\255\350')"*) ;; # '\x8e\xad\xe8'
+ *) fatal "File doesn't look like rpm: $pkg" ;;
+ esac
+
  offset=$(($1 + 8))
 
  local i b b0 b1 b2 b3 b4 b5 b6 b7