From 0760b6f237449febb56225a42c258c6d43282024 Mon Sep 17 00:00:00 2001
From: Jonathon Hall <jonathon.hall@puri.sm>
Date: Mon, 13 Mar 2023 12:26:41 -0400
Subject: [PATCH] init: Use busybox ash

init must use busybox ash because it is used on legacy-flash boards.
Change shebang, move needed functions to ash_functions.

Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
---
 initrd/etc/ash_functions | 43 ++++++++++++++++++++++++++++++++++++++++
 initrd/etc/functions     | 42 ---------------------------------------
 initrd/init              |  7 +++++--
 3 files changed, 48 insertions(+), 44 deletions(-)

diff --git a/initrd/etc/ash_functions b/initrd/etc/ash_functions
index f4ff9193..9156fae5 100644
--- a/initrd/etc/ash_functions
+++ b/initrd/etc/ash_functions
@@ -42,3 +42,46 @@ preserve_rom() {
 		fi
 	done
 }
+
+recovery() {
+	TRACE "Under /etc/functions:recovery"
+	echo >&2 "!!!!! $*"
+
+	# Remove any temporary secret files that might be hanging around
+	# but recreate the directory so that new tools can use it.
+
+	#safe to always be true. Otherwise "set -e" would make it exit here
+	shred -n 10 -z -u /tmp/secret/* 2> /dev/null || true
+	rm -rf /tmp/secret
+	mkdir -p /tmp/secret
+
+	# ensure /tmp/config exists for recovery scripts that depend on it
+	touch /tmp/config
+
+	if [ "$CONFIG_TPM" = "y" ]; then
+		tpmr extend -ix 4 -ic recovery
+	fi
+
+	while [ true ]
+	do
+		echo >&2 "!!!!! Starting recovery shell"
+		sleep 1
+
+		if [ -x /bin/setsid ]; then
+			/bin/setsid -c /bin/sh
+		else
+			/bin/sh
+		fi
+	done
+}
+
+pause_recovery() {
+	TRACE "Under /etc/functions:pause_recovery"
+	read -p $'!!! Hit enter to proceed to recovery shell !!!\n'
+	recovery $*
+}
+
+combine_configs() {
+	TRACE "Under /etc/functions:combine_configs"
+	cat /etc/config* > /tmp/config
+}
diff --git a/initrd/etc/functions b/initrd/etc/functions
index e36c85e8..14da231a 100755
--- a/initrd/etc/functions
+++ b/initrd/etc/functions
@@ -33,44 +33,6 @@ DO_WITH_DEBUG() {
 	"$@"
 }
 
-recovery() {
-	TRACE "Under /etc/functions:recovery"
-	echo >&2 "!!!!! $*"
-
-	# Remove any temporary secret files that might be hanging around
-	# but recreate the directory so that new tools can use it.
-
-	#safe to always be true. Otherwise "set -e" would make it exit here
-	shred -n 10 -z -u /tmp/secret/* 2> /dev/null || true
-	rm -rf /tmp/secret
-	mkdir -p /tmp/secret
-
-	# ensure /tmp/config exists for recovery scripts that depend on it
-	touch /tmp/config
-
-	if [ "$CONFIG_TPM" = "y" ]; then
-		tpmr extend -ix 4 -ic recovery
-	fi
-
-	while [ true ]
-	do
-		echo >&2 "!!!!! Starting recovery shell"
-		sleep 1
-
-		if [ -x /bin/setsid ]; then
-			/bin/setsid -c /bin/sh
-		else
-			/bin/sh
-		fi
-	done
-}
-
-pause_recovery() {
-	TRACE "Under /etc/functions:pause_recovery"
-	read -p $'!!! Hit enter to proceed to recovery shell !!!\n'
-	recovery $*
-}
-
 pcrs() {
 	if [ "$CONFIG_TPM2_TOOLS" = "y" ]; then
 		tpm2 pcrread sha256
@@ -345,10 +307,6 @@ replace_config() {
   sort ${CONFIG_FILE}.tmp | uniq > ${CONFIG_FILE}
 	rm -f ${CONFIG_FILE}.tmp
 }
-combine_configs() {
-	TRACE "Under /etc/functions:combine_configs"
-	cat /etc/config* > /tmp/config
-}
 
 update_checksums()
 {
diff --git a/initrd/init b/initrd/init
index 6b03279b..445722df 100755
--- a/initrd/init
+++ b/initrd/init
@@ -1,4 +1,7 @@
-#!/bin/bash
+#! /bin/ash
+# Note this is used on legacy-flash boards that lack bash, it runs with busybox
+# ash.  Calls to bash scripts must be guarded by checking config.
+
 mknod /dev/ttyprintk c 5 3
 echo "hello world" > /dev/ttyprintk
 
@@ -48,7 +51,7 @@ fi
 hwclock -l -s
 
 # Read the system configuration parameters
-. /etc/functions
+. /etc/ash_functions
 . /etc/config
 
 TRACE "Under init"