From a89376008a91a4b4f9f971248047529e4bfd649c Mon Sep 17 00:00:00 2001
From: Zed <zedeus@pm.me>
Date: Wed, 22 Jan 2020 15:22:06 +0100
Subject: [PATCH] Bypass A/B testing by restricting user agents

---
 src/agents.nim | 96 +++++++++++++-------------------------------------
 1 file changed, 25 insertions(+), 71 deletions(-)

diff --git a/src/agents.nim b/src/agents.nim
index 1703e9b..dbbee0d 100644
--- a/src/agents.nim
+++ b/src/agents.nim
@@ -1,115 +1,69 @@
-import random, strformat, strutils
+import random, strformat, strutils, sequtils
 
 randomize()
 
 const rvs = [
   "11.0", "40.0", "42.0", "43.0", "47.0", "50.0", "52.0", "53.0", "54.0",
-  "61.0", "66.0", "67.0"
+  "61.0", "66.0", "67.0", "69.0", "70.0"
 ]
 
 proc rv(): string =
-  if rand(5) < 3: ""
+  if rand(10) < 1: ""
   else: "; rv:" & sample(rvs)
 
 # OS
 
+const enc = ["; U", "; N", "; I", ""]
+
 proc linux(): string =
   const
-    arch = ["i686", "x86_64"]
-    distro = ["", "; Ubuntu/14.10", "; Ubuntu/16.10", "; Ubuntu/19.10", "; Ubuntu"]
-  "X11; Linux " & sample(arch) & sample(distro)
+    window = ["X11", "Wayland", "Unknown"]
+    arch = ["i686", "x86_64", "arm"]
+    distro = ["", "; Ubuntu/14.10", "; Ubuntu/16.10", "; Ubuntu/19.10",
+              "; Ubuntu", "; Fedora"]
+  sample(window) & sample(enc) & "; Linux " & sample(arch) & sample(distro)
 
 proc windows(): string =
   const
     nt = ["5.1", "5.2", "6.0", "6.1", "6.2", "6.3", "6.4", "9.0", "10.0"]
     arch = ["; WOW64", "; Win64; x64", "; ARM", ""]
     trident = ["", "; Trident/5.0", "; Trident/6.0", "; Trident/7.0"]
-  "Windows " & sample(nt) & sample(arch) & sample(trident)
+  "Windows " & sample(nt) & sample(enc) & sample(arch) & sample(trident)
+
+let macs = toSeq(6..15).mapIt($it) & @["14_4", "10_1", "9_3"]
 
 proc mac(): string =
-  const v = ["Intel Mac OS X 10_12", "Intel Mac OS X 10_11", "Intel Mac OS X 10_10_1",
-              "Intel Mac OS X 10_9_3"]
-  "Macintosh; " & sample(v)
+  "Macintosh; Intel Mac OS X 10_" & sample(macs) & sample(enc)
 
 # Browser
 
-const safariV = [
-  "536.25", "536.26", "536.26.17", "536.28.10", "536.29.13", "536.30.1",
-  "537.32", "537.36", "537.43.58", "537.73.11", "537.85.17", "537.71",
-  "537.73.11", "537.75.14", "537.76.4", "537.77.4", "537.78.2",
-  "537.85.17", "538.35.8", "600.6.3", "600.7.12", "601.1.56", "601.2.7",
-  "601.3.9", "601.4.4", "601.5.17", "601.6.17", "601.7.1", "601.7.8",
-  "602.1.50", "602.2.14", "602.3.12", "602.4.8", "603.1.30", "603.2.4",
-  "603.3.8", "604.1.28"
-]
-
-proc appleWebKit(): string =
-  "AppleWebKit/" & sample(safariV) & " (KHTML, like Gecko) "
-
-proc safari(): string =
-  const edge = ["", "", " Edge/16.16299"]
-  " Safari/" & sample(safariV) & sample(edge)
-
-proc chrome(): string =
-  const v = [
-    "41.0.2224.3", "41.0.2225.0", "41.0.2226.0", "41.0.2227.0", "41.0.2227.1",
-    "41.0.2228.0", "49.0.2623.112", "57.0.2987.133", "58.0.3029.110",
-    "59.0.3071.115", "61.0.3163.100", "63.0.3239.132", "63.0.3239.84",
-    "64.0.3282.186", "65.0.3325.181", "67.0.3396.99", "68.0.3440.106",
-    "69.0.3497.100", "70.0.3538.102", "70.0.3538.110", "70.0.3538.77",
-    "72.0.3626.121", "74.0.3729.131"]
-  "Chrome/" & sample(v)
-
-proc firefox(): string =
-  const v = [
-    "38.0", "40.1", "43.0", "50.0", "52.0", "53.0", "60.0", "60.0.2", "60.0.1",
-    "61.0", "61.0.1", "66.0", "67.0"]
-  "Gecko/20100101 Firefox/" & sample(v)
-
 proc presto(): string =
-  const p = ["2.12.388", "2.12.407", "22.9.168"]
-  const v = ["12.00", "12.14", "12.16"]
+  const p = ["2.12.388", "2.12.407", "22.9.168", "2.9.201", "2.8.131", "2.7.62",
+             "2.6.30", "2.5.24"]
+  const v = ["10.0", "11.0", "11.1", "11.5", "11.6", "12.00", "12.14", "12.16"]
   &"Presto/{sample(p)} Version/{sample(v)}"
 
-proc opr(): string =
-  const v = [
-    "43.0.2442.991", "36.0.2130.32", "56.0.3051.52", "47.0.2631.39",
-    "42.0.2393.94", "49.0.2711.0", "34.0.2036.25", "52.0.2871.99",
-    "33.0.1990.115", "53.0.2907.99"
-  ]
-  " OPR/" & sample(v)
-
 # Samples
 
 proc product(): string =
   const opera = ["Opera/9.80", "Opera/12.0"]
-  if rand(10) < 8: "Mozilla/5.0"
+  if rand(20) < 1: "Mozilla/5.0"
   else: sample(opera)
 
 proc os(): string =
+  let r = rand(10)
   let os =
-    case rand(2)
-    of 0: linux()
-    of 1: windows()
+    if r < 6: windows()
+    elif r < 9: linux()
     else: mac()
   &"({os}{rv()})"
 
-proc browser(os: string; prod: string): string =
-  if "Opera" in prod:
-    if rand(1) == 0: return presto()
-    else: return appleWebKit() & chrome() & safari() & opr()
-
-  if "X11" in os and "rv" notin os:
-    return appleWebKit() & chrome() & safari()
-
-  let r = rand(100)
-  if r < 5: "like Gecko"
-  elif r < 50: appleWebKit() & chrome() & safari()
-  else: firefox()
+proc browser(prod: string): string =
+  if "Opera" in prod: presto()
+  else: "like Gecko"
 
 # Agent
 
 proc getAgent*(): string =
   let prod = product()
-  let os = os()
-  result = &"{prod} {os} {browser(os, prod)}"
+  &"{prod} {os()} {browser(prod)}"