1 files changed, 80 insertions, 0 deletions
diff --git a/contrib/examples/extract-handshakes/extract-handshakes.sh b/contrib/examples/extract-handshakes/extract-handshakes.sh
new file mode 100755
index 0000000..16ed630
--- /dev/null
+++ b/contrib/examples/extract-handshakes/extract-handshakes.sh
@@ -0,0 +1,80 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Copyright (C) 2015-2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+# Copyright (C) 2017-2018 Peter Wu <peter@lekensteyn.nl>. All Rights Reserved.
+
+set -e
+
+ME_DIR="${BASH_SOURCE[0]}"
+ME_DIR="${ME_DIR%/*}"
+source "$ME_DIR/offsets.include" || { echo "Did you forget to run make?" >&2; exit 1; }
+
+case "$(uname -m)" in
+	x86_64) ARGUMENT_REGISTER="%si" ;;
+	i386|i686) ARGUMENT_REGISTER="%dx" ;;
+	aarch64) ARGUMENT_REGISTER="%x1" ;;
+	arm) ARGUMENT_REGISTER="%r1" ;;
+	*) echo "ERROR: Unknown architecture" >&2; exit 1 ;;
+esac
+
+ARGS=( )
+REGEX=".*: idxadd: .*"
+for key in "${!OFFSETS[@]}"; do
+	values="${OFFSETS[$key]}"
+	values=( ${values//,/ } )
+	for i in {0..3}; do
+		value="$ARGUMENT_REGISTER"
+		for indirection in "${values[@]:1}"; do
+			value="+$indirection($value)"
+		done
+		value="+$((i * 8 + values[0]))($value)"
+		ARGS+=( "${key,,}$i=$value:x64" )
+		REGEX="$REGEX ${key,,}$i=0x([0-9a-f]+)"
+	done
+done
+
+turn_off() {
+	set +e
+	[[ -f /sys/kernel/debug/tracing/events/wireguard/idxadd/enable ]] || exit
+	echo 0 > /sys/kernel/debug/tracing/events/wireguard/idxadd/enable
+	echo "-:wireguard/idxadd" >> /sys/kernel/debug/tracing/kprobe_events
+	exit
+}
+
+trap turn_off INT TERM EXIT
+echo "p:wireguard/idxadd index_hashtable_insert ${ARGS[*]}" >> /sys/kernel/debug/tracing/kprobe_events
+echo 1 > /sys/kernel/debug/tracing/events/wireguard/idxadd/enable
+
+unpack_u64() {
+	local i expanded="$1"
+	if [[ $ENDIAN == big ]]; then
+		printf -v expanded "%.*s$expanded" $((16 - ${#expanded})) 0000000000000000
+		for i in {0..7}; do
+			echo -n "\\x${expanded:(i * 2):2}"
+		done
+	elif [[ $ENDIAN == little ]]; then
+		(( ${#expanded} % 2 == 1 )) && expanded="0$expanded"
+		expanded="${expanded}0000000000000000"
+		for i in {0..7}; do
+			echo -n "\\x${expanded:((7 - i) * 2):2}"
+		done
+	else
+		echo "ERROR: Unable to determine endian" >&2
+		exit 1
+	fi
+}
+
+while read -r line; do
+	[[ $line =~ $REGEX ]] || continue
+	echo "New handshake session:"
+	j=1
+	for key in "${!OFFSETS[@]}"; do
+		bytes=""
+		for i in {0..3}; do
+			bytes="$bytes$(unpack_u64 "${BASH_REMATCH[j]}")"
+			((++j))
+		done
+		echo "  $key = $(printf "$bytes" | base64)"
+	done
+done < /sys/kernel/debug/tracing/trace_pipe