diff --git a/howto.md b/howto.md index 2e0e487..6085af2 100644 --- a/howto.md +++ b/howto.md @@ -1,4 +1,4 @@ -header +mDNS howto Documentation ===== How to create a JSON file with information about your project: @@ -10,7 +10,7 @@ How to duplicate DNS crash: ``` >> cd ~/dns_test ->> node listen.js +>> node listen.jss ``` Then in another terminal enter: @@ -64,12 +64,70 @@ RangeError: Index out of range which is located in the node.js buffer module. The API is [here](https://nodejs.org/api/buffer.html). However, the error we are working with will most likely be dealt with by parsing through the binary -and putting it in a format that is acceptable to a custom buffer, since the current buffer.js does -doesn't seem to do the trick. +and putting it in a format that is acceptable to a custom buffer, since the current buffer.js does doesn't seem to do the trick. -Binary +Using -When can a Buffer overflow problem occur in js? +```javascript +function pad(str, len, ch) { + + while (str.length < len) { + str = ch + str; + } + + return str; +} +``` +the binary output comes out as: + +``` +11100001 +10001000 +00000001 +00100000 +00000000 +00000001 +00000000 +00000000 +00000000 +00000000 +00000000 +00000001 +00000110 +01011111 +01100011 +01101100 +01101111 +01110101 +01100100 +00000100 +01011111 +01110100 +01100011 +01110000 +00000101 +01101100 +01101111 +01100011 +01100001 +01101100 +00000000 +00000000 +00001100 +00000000 +00000001 +00000000 +00000000 +00101001 +00010000 +00000000 +00000000 +00000000 +00000000 +00000000 +00000000 +00000000 +``` What are the possible problems? @@ -84,4 +142,6 @@ socket.on('message', function (message, rinfo) { //console.log(msg.toString('utf8')); console.log(message.toString('hex')); -``` \ No newline at end of file +``` + +###Objective