randstruct: Move seed generation into scripts/basic/
To enable Clang randstruct support, move the structure layout
randomization seed generation out of scripts/gcc-plugins/ into
scripts/basic/ so it happens early enough that it can be used by either
compiler implementation. The gcc-plugin still builds its own header file,
but now does so from the common "randstruct.seed" file.
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
diff --git a/scripts/gen-randstruct-seed.sh b/scripts/gen-randstruct-seed.sh
new file mode 100755
index 0000000..61017b3
--- /dev/null
+++ b/scripts/gen-randstruct-seed.sh
@@ -0,0 +1,7 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+SEED=$(od -A n -t x8 -N 32 /dev/urandom | tr -d ' \n')
+echo "$SEED" > "$1"
+HASH=$(echo -n "$SEED" | sha256sum | cut -d" " -f1)
+echo "#define RANDSTRUCT_HASHED_SEED \"$HASH\"" > "$2"