Add a bunch of TRACE_FUNC and make sure DEBUG calls can inject their …

…output to kmesg

DEBUG function modified to split on last space before reaching safe max 960 characters

This max characters lenght to be passed to kmesg was roughtly determined by PREFIX_MAX taken into consideration for LOG_LINE_MAX of printk of oldest 5.5.x kernel we need to respect:
grep: build/ppc64/linux-5.5/linux-talos-2/source: warning: recursive directory loop
build/ppc64/linux-5.5/kernel/printk/printk.c:446:#define PREFIX_MAX		48
build/ppc64/linux-5.5/kernel/printk/printk.c:448:#define PREFIX_MAX		32
build/ppc64/linux-5.5/kernel/printk/printk.c:450:#define LOG_LINE_MAX		(1024 - PREFIX_MAX)
build/ppc64/linux-5.5/kernel/printk/printk.c:1315:	char prefix[PREFIX_MAX];
build/ppc64/linux-5.5/kernel/printk/printk.c:1356:	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
build/ppc64/linux-5.5/kernel/printk/printk.c:1386:				   LOG_LINE_MAX + PREFIX_MAX);
build/ppc64/linux-5.5/kernel/printk/printk.c:1428:	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);
build/ppc64/linux-5.5/kernel/printk/printk.c:1466:					     LOG_LINE_MAX + PREFIX_MAX);
build/ppc64/linux-5.5/kernel/printk/printk.c:2066:#define PREFIX_MAX		0
build/ppc64/linux-5.5/kernel/printk/printk.c:2370:	static char text[LOG_LINE_MAX + PREFIX_MAX];
build/ppc64/linux-5.5/include/uapi/linux/rtnetlink.h:552:	__PREFIX_MAX
build/ppc64/linux-5.5/include/uapi/linux/rtnetlink.h:555:#define PREFIX_MAX	(__PREFIX_MAX - 1)
build/ppc64/linux-5.5/linux-5.5/linux-talos-2/usr/include/linux/rtnetlink.h:552:	__PREFIX_MAX
build/ppc64/linux-5.5/linux-5.5/linux-talos-2/usr/include/linux/rtnetlink.h:555:#define PREFIX_MAX	(__PREFIX_MAX - 1)

Each DEBUG call also adds "DEBUG: " leaving us to a safe 960 char limit to respect and wrap around.

Otherwise, calling DEBUG fails from scripts setting "set -e -o pipefail"

Signed-off-by: Thierry Laurion <[email protected]>

initrd/bin/kexec-insert-key

@@ -29,6 +29,7 @@ if [ -r "$TMP_KEY_LVM" ]; then
 fi
 
 # Measure the LUKS headers before we unseal the disk key
+TRACE_FUNC
 cat "$TMP_KEY_DEVICES" | cut -d\  -f1 | xargs /bin/qubes-measure-luks ||
 	die "LUKS measure failed"
 
@@ -43,6 +44,7 @@ mkdir -p "$INITRD_DIR/etc"
 # Attempt to unseal the disk key from the TPM
 # should we give this some number of tries?
 unseal_failed="n"
+TRACE_FUNC
 if ! kexec-unseal-key "$INITRD_DIR/secret.key"; then
 	unseal_failed="y"
 	echo
@@ -51,6 +53,7 @@ fi
 
 # Override PCR 4 so that user can't read the key
 DEBUG "Extending TPM PCR 4 to prevent further secret unsealing"
+TRACE_FUNC
 tpmr extend -ix 4 -ic generic ||
 	die 'Unable to scramble PCR'
 
@@ -70,6 +73,7 @@ if [ "$unseal_failed" = "y" ]; then
 	fi
 fi
 
+TRACE_FUNC
 echo
 echo '+++ Building initrd'
 # pad the initramfs (dracut doesn't pad the last gz blob)

initrd/bin/kexec-unseal-key

@@ -3,7 +3,6 @@
 # The TOTP secret will be shown to the user on each encryption attempt.
 # It will then need to be bundled into initrd that is booted with Qubes.
 set -e -o pipefail
-. /etc/functions
 
 TPM_INDEX=3
 TPM_SIZE=312

initrd/etc/ash_functions

@@ -23,13 +23,15 @@ warn() {
 }
 
 DEBUG() {
-	if [ "$CONFIG_DEBUG_OUTPUT" = "y" ];then
-		echo "DEBUG: $*" | while read line; do
+	if [ "$CONFIG_DEBUG_OUTPUT" = "y" ]; then
+		# fold -s -w 960 will wrap lines at 960 characters on the last space before the limit
+		echo "DEBUG: $*" | fold -s -w 960 | while read line; do
 			echo "$line" | tee -a /tmp/debug.log /dev/kmsg >/dev/null
 		done
 	fi
 }
 
+
 TRACE() {
 	if [ "$CONFIG_ENABLE_FUNCTION_TRACING_OUTPUT" = "y" ];then
 		echo "TRACE: $*" | tee -a /tmp/debug.log /dev/kmsg > /dev/null;

initrd/etc/functions

@@ -695,12 +695,14 @@ scan_boot_options() {
 }
 
 calc() {
+	TRACE_FUNC
 	awk "BEGIN { print "$*" }"
 }
 
 # truncate a file to a size only if it is longer (busybox truncate lacks '<' and
 # always sets the file size)
 truncate_max_bytes() {
+	TRACE_FUNC
 	local bytes="$1"
 	local file="$2"
 	if [ "$(stat -c %s "$file")" -gt "$bytes" ]; then
@@ -712,6 +714,7 @@ truncate_max_bytes() {
 # trips up many scripts, it's very difficult to diagnose by looking at the
 # output.  Delete line breaks and spaces to really get plain hex output.
 tohex_plain() {
+	TRACE_FUNC
 	xxd -p | tr -d '\n '
 }
 
@@ -721,24 +724,28 @@ tohex_plain() {
 # Note that also unlike GNU xxd, non-hex chars in input corrupt the output (GNU
 # xxd ignores them).
 fromhex_plain() {
+	TRACE_FUNC
 	fold -w 60 | xxd -p -r
 }
 
 print_battery_health() {
+	TRACE_FUNC
 	if [ -d /sys/class/power_supply/BAT* ]; then
 		battery_health=$(calc $(cat /sys/class/power_supply/BAT*/charge_full)/$(cat /sys/class/power_supply/BAT*/charge_full_design)*100 | awk -F "." {'print $1'})
 		echo "$battery_health"
 	fi
 }
 
 print_battery_charge() {
+	TRACE_FUNC
 	if [ -d /sys/class/power_supply/BAT* ]; then
 		battery_charge=$(calc $(cat /sys/class/power_supply/BAT*/charge_now)/$(cat /sys/class/power_supply/BAT*/charge_full)*100 | awk -F "." {'print $1'})
 		echo "$battery_charge"
 	fi
 }
 
 generate_random_mac_address() {
+	TRACE_FUNC
 	#Borrowed from https://stackoverflow.com/questions/42660218/bash-generate-random-mac-address-unicast
 	hexdump -n 6 -ve '1/1 "%.2x "' /dev/urandom | awk -v a="2,6,a,e" -v r="$RANDOM" 'BEGIN{srand(r);}NR==1{split(a,b,",");r=int(rand()*4+1);printf "%s%s:%s:%s:%s:%s:%s\n",substr($1,0,1),b[r],$2,$3,$4,$5,$6}'
 }