Fix signature extraction

6 years ago · 9d5dddab29
parent 45fa148380
commit 9d5dddab29
1 changed files with 10 additions and 12 deletions
--- a/src/invidious/signatures.cr
+++ b/src/invidious/signatures.cr
@ -4,22 +4,21 @@ def fetch_decrypt_function(client, id = "CvFH_6DNRCY")
  player = client.get(url).body

  function_name = player.match(/"signature",(?<name>[a-zA-Z0-9]{2})\(/).not_nil!["name"]
-  function_body = player.match(/#{function_name}=function\(a\){(?<body>[^}]+)}/).not_nil!["body"]
+  function_body = player.match(/^#{function_name}=function\(a\){(?<body>[^}]+)}/m).not_nil!["body"]
  function_body = function_body.split(";")[1..-2]

  var_name = function_body[0][0, 2]
+  var_body = player.delete("\n").match(/var #{var_name}={(?<body>(.*?))};/).not_nil!["body"]

  operations = {} of String => String
-  matches = player.delete("\n").match(/var #{var_name}={(?<op1>[a-zA-Z0-9]{2}:[^}]+}),(?<op2>[a-zA-Z0-9]{2}:[^}]+}),(?<op3>[a-zA-Z0-9]{2}:[^}]+})};/).not_nil!
-  3.times do |i|
-    operation = matches["op#{i + 1}"]
-    op_name = operation[0, 2]
+  var_body.split("},").each do |operation|
+    op_name = operation.match(/^[^:]+/).not_nil![0]
+    op_body = operation.match(/\{[^}]+/).not_nil![0]

-    op_body = operation.match(/\{[^}]+\}/).not_nil![0]
    case op_body
-    when "{a.reverse()}"
+    when "{a.reverse()"
      operations[op_name] = "a"
-    when "{a.splice(0,b)}"
+    when "{a.splice(0,b)"
      operations[op_name] = "b"
    else
      operations[op_name] = "c"
@ -28,11 +27,10 @@ def fetch_decrypt_function(client, id = "CvFH_6DNRCY")

  decrypt_function = [] of {name: String, value: Int32}
  function_body.each do |function|
-    function = function.lchop(var_name + ".")
-    op_name = function[0, 2]
+    function = function.lchop(var_name).delete("[].")

-    function = function.lchop(op_name + "(a,")
-    value = function.rchop(")").to_i
+    op_name = function.match(/[^\(]+/).not_nil![0]
+    value = function.match(/\(a,(?<value>[\d]+)\)/).not_nil!["value"].to_i

    decrypt_function << {name: operations[op_name], value: value}
  end