Mac Archive Type Sniffing

chrome/test/data/safe_browsing/dmg/generate_test_data.sh

Index: chrome/test/data/safe_browsing/dmg/generate_test_data.sh
diff --git a/chrome/test/data/safe_browsing/dmg/generate_test_data.sh b/chrome/test/data/safe_browsing/dmg/generate_test_data.sh
index a1a6b6557c2be91a85ce69b8e19204e0592eee1c..0bdb4e5591fa3f1f37cbdae0f7893615ee0c238c 100755
--- a/chrome/test/data/safe_browsing/dmg/generate_test_data.sh
+++ b/chrome/test/data/safe_browsing/dmg/generate_test_data.sh
@@ -84,6 +84,23 @@ generate_test_data() {
     "${OUT_DIR}/mach_o_in_dmg"
 
   rm -rf "${DMG_SOURCE}"
+
+  # Copy of Mach-O DMG with 'koly' signature overwritten #######################
+  cp "${OUT_DIR}/mach_o_in_dmg.dmg" \
+  "${OUT_DIR}/mach_o_in_dmg_no_koly_signature.dmg"

[Robert Sesek, 2017/06/12 16:38:39]

nit: indent continuation lines by 4 spaces so it's  clear that this is not a new
command

[mortonm, 2017/06/12 18:31:16]

Done.

+  # Gets size of Mach-O DMG copy.
+  SIZE=`stat -f%z "${OUT_DIR}/mach_o_in_dmg_no_koly_signature.dmg"`
+  # Overwrites 'koly' with '????'.
+  printf '\xa1\xa1\xa1\xa1' | dd conv=notrunc \
+  of="${OUT_DIR}/mach_o_in_dmg_no_koly_signature.dmg" bs=1 seek=$(($SIZE - 512))
+
+  # Copy of Mach-O DMG with extension changed to .txt.
+  cp "${OUT_DIR}/mach_o_in_dmg.dmg" "${OUT_DIR}/mach_o_in_dmg.txt"
+
+  # Copy of Mach-O DMG with extension changed to .txt and no 'koly' signature ##
+  cp "${OUT_DIR}/mach_o_in_dmg_no_koly_signature.dmg" \
+  "${OUT_DIR}/mach_o_in_dmg_no_koly_signature.txt"
+

[Robert Sesek, 2017/06/12 16:38:39]

nit: extra blank line

[mortonm, 2017/06/12 18:31:16]

Done.

 }
 
 # Silence any stdout, but keep stderr.