From 088648409e99abc1a46df284c00052aea14067aa Mon Sep 17 00:00:00 2001
From: bunnie <bunnie@kosagi.com>
Date: Sun, 11 Sep 2022 19:13:38 +0800
Subject: [PATCH] add constant time analysis script

---
 tools/ct_analyze.py | 98 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100644 tools/ct_analyze.py

diff --git a/tools/ct_analyze.py b/tools/ct_analyze.py
new file mode 100644
index 000000000..61cc248c3
--- /dev/null
+++ b/tools/ct_analyze.py
@@ -0,0 +1,98 @@
+#! /usr/bin/env python3
+import argparse
+import re
+import numpy as np
+from PIL import Image as im
+import random
+import os
+
+def randomize_palette(img):
+    palette = img.getpalette()
+    rand_palette = []
+    for i in palette:
+        rand_palette.append(random.randint(0, 255))
+    img.putpalette(rand_palette)
+    return img
+
+def convert_to_image(times):
+    thresh = times.mean() * 2
+    times.clip(min=0, max=thresh)
+    times = times * (255 / thresh)
+
+    img = im.new("P", (256, 128))
+    x = 0
+    y = 0
+    for k in times.astype(int):
+        for d in k:
+            img.putpixel((x, y), int(d))
+            y += 1
+            y %= 128
+        x += 1
+        x %= 256
+
+    return img
+
+def main():
+    parser = argparse.ArgumentParser(description="Analyze performance logs")
+    parser.add_argument(
+        "--file", default=False, help="file to analyze", type=str
+    )
+    args = parser.parse_args()
+
+    if args.file is None:
+        print("Must specify a file to analyze with --file")
+        exit(0)
+
+    rootname = os.path.splitext(args.file)[0]
+
+    rekey_start = 0
+    enc_start = 0
+    enc_times = np.arange(256*128).reshape((256, 128))
+    rekey_times = np.arange(256*128).reshape((256, 128))
+    with open(args.file, "r", encoding='utf-8', errors='replace') as f:
+        lines = f.readlines()
+        for line in lines:
+            if '== restart ==' in line:
+                rekey_start = 0
+            rgx = re.search('.*net_cmd: ([0-9]*):([0-9]*):([0-9]*).*', line)
+            if rgx is not None:
+                perfdata = rgx.groups()
+                timestamp = int(perfdata[1])
+                code = int(perfdata[2])
+                keybit = code & 0xFF
+                databit = (code >> 8) & 0xFF
+                start = (code & 0x100_0000) == 0
+                if start:
+                    rekey_times[keybit][databit] = timestamp - rekey_start
+                    enc_start = timestamp
+                else:
+                    enc_times[keybit][databit] = timestamp - enc_start
+                    rekey_start = timestamp
+
+    #print('enc time sample')
+    #for i in range(32):
+    #    print('{}'.format(enc_times[i]))
+    #print('rekey time sample')
+    #print('{}'.format(rekey_times[0]))
+    print("enc: mean {} / max {}".format(enc_times.mean(), enc_times.max()))
+    enc_hist = np.histogram(enc_times, bins=32)
+    print(enc_hist)
+    print("enc typical cycles: {}".format(enc_hist[1][0]))
+    print("rekey: mean {} / max {}".format(rekey_times.mean(), rekey_times.max()))
+    rk_hist = np.histogram(rekey_times, bins=32)
+    print(rk_hist)
+    print("rekey typical cycles: {}".format(rk_hist[1][0]))
+
+    enc = convert_to_image(enc_times)
+    enc.convert("RGB").save(rootname + '_enc.png')
+    enc_r = randomize_palette(enc)
+    enc_r.convert("RGB").save(rootname + '_enc_r.png')
+
+    rk = convert_to_image(rekey_times)
+    rk.convert("RGB").save(rootname + '_rekey.png')
+    rk_r = randomize_palette(rk)
+    rk_r.convert("RGB").save(rootname + '_rekey_r.png')
+
+if __name__ == "__main__":
+    main()
+    exit(0)