How to use the JavaScript API correctly?

[migueldilaj]

Hi!
Tried a Run Script Then as follows:

console.log('Tring to obtain variable');
console.log(getMessageValueKeys());

It failed with this error:

{
  "message" : "Script Log",
  "payload" : "Tring to obtain variable"
}
{
  "message" : "Failure running rule",
  "exception" : "ReferenceError: \"getMessageValueKeys\" is not defined. (#2)\norg.mozilla.javascript.EcmaError: ReferenceError: \"getMessageValueKeys\" is not defined. (#2)\n\tat org.mozilla.javascript.ScriptRuntime.constructError(ScriptRuntime.java:4280)\n\tat org.mozilla.javascript.ScriptRuntime.constructError(ScriptRuntime.java:4258)\n\tat org.mozilla.javascript.ScriptRuntime.notFoundError(ScriptRuntime.java:4348)\n\tat org.mozilla.javascript.ScriptRuntime.getNameFunctionAndThis(ScriptRuntime.java:2462)\n\tat org.mozilla.javascript.optimizer.OptRuntime.callName0(OptRuntime.java:85)\n\tat org.mozilla.javascript.gen._cmd__9._c_script_0(:2)\n\tat org.mozilla.javascript.gen._cmd__9.call()\n\tat org.mozilla.javascript.ContextFactory.doTopCall(ContextFactory.java:412)\n\tat org.mozilla.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3578)\n\tat org.mozilla.javascript.gen._cmd__9.call()\n\tat org.mozilla.javascript.gen._cmd__9.exec()\n\tat org.mozilla.javascript.Context.evaluateString(Context.java:1234)\n\tat synfron.reshaper.burp.core.rules.thens.ThenRunScript.lambda$perform$0(ThenRunScript.java:25)\n\tat synfron.reshaper.burp.core.rules.thens.entities.script.Dispatcher.lambda$getRunner$0(Dispatcher.java:53)\n\tat java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)\n\tat java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)\n\tat java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630)\n\tat java.base/java.lang.Thread.run(Thread.java:831)\n",
  "payload" : "\tat :2\n"
}

Any advise on what I'm doing wrong will be much appreciated!

[ddwightx]

Looks you like actually wanted Reshaper.event.getMessageValueKeys(). The documentation may be a little confusing in that area, but the section header titles of that page https://synfron.github.io/ReshaperForBurp/ScriptingLibrary.html are the prefixes that need to go before the function call.

[migueldilaj]

Perfect! Thanks for the advice. The calls work as intended now.

[AkikoOrenji]

Sorry to hijack but i'm struggling with the following

console.log('Test');
console.log(Reshaper.variables.getGlobalVariable(value4));

Am i missing something as i get the following:

_{
"message" : "Failure running rule",
"exception" : "ReferenceError: "value4" is not defined. (#2)\norg.mozilla.javascript.EcmaError: ReferenceError: "value4" is not defined. (#2)\r\n\tat org.mozilla.javascript.ScriptRuntime.constructError(ScriptRuntime.java:4563)\r\n\tat org.mozilla.javascript.ScriptRuntime.constructError(ScriptRuntime.java:4544)\r\n\tat org.mozilla.javascript.ScriptRuntime.notFoundError(ScriptRuntime.java:4632)\r\n\tat org.mozilla.javascript.ScriptRuntime.name(ScriptRuntime.java:1952)\r\n\tat org.mozilla.javascript.gen._cmd__5._c_script_0(:2)\r\n\tat org.mozilla.javascript.gen._cmd__5.call()\r\n\tat org.mozilla.javascript.ContextFactory.doTopCall(ContextFactory.java:380)\r\n\tat org.mozilla.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3868)\r\n\tat org.mozilla.javascript.gen._cmd__5.call()\r\n\tat org.mozilla.javascript.gen.cmd__5.exec()\r\n\tat org.mozilla.javascript.Context.evaluateString(Context.java:1137)\r\n\tat synfron.reshaper.burp.core.rules.thens.ThenRunScript.lambda$perform$0(ThenRunScript.java:26)\r\n\tat synfron.reshaper.burp.core.rules.thens.entities.script.Dispatcher.lambda$getRunner$0(Dispatcher.java:53)\r\n\tat java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)\r\n\tat java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)\r\n\tat java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)\r\n\tat java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)\r\n\tat java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630)\r\n\tat java.base/java.lang.Thread.run(Thread.java:831)\r\n",
"payload" : "\tat :2\r\n"
}

I also tried global:value4 but get a different error. I assume i dont need 'global:' suffix as its implied in the function name (getGlobalVariable)

thanks

[ddwightx]

Hi @AkikoOrenji console.log(Reshaper.variables.getGlobalVariable(value4)); should be console.log(Reshaper.variables.getGlobalVariable("value4"));

[AkikoOrenji]

thanks. Rookie mistake. Working fine now.
Might as well share my full example incase anyone else comes looking for one. Using the Run Script Then to strip all newlines and CRs from a variable before use in another Then step.

var x = Reshaper.variables.getGlobalVariable("value4")
x = x.replace(/[\n\r]+/g, '');
Reshaper.variables.setGlobalVariable("value5", x)

[ddwightx]

@AkikoOrenji FYI, you can also just use Set Variable to do what you need:

1. Add a Set Variable then
2. Uncheck Use Message Value
3. Set Source Text = {{global:value4}}
4. Check Use Regex Replace
5. Set Regex Pattern = [\n\r]+
6. Set Destination Variable Name = value5

[AkikoOrenji]

oh thanks for the extra tip.