Javascript encryptor XOR

[polychrom]

Is there some handy Javascript encryptor based on XOR algorithm? (html
page with encoded javascript will have a "decoder stub" prefixed before
the code that is actually executed.)

 

[Lasse Reichstein Nielsen]

Is there some handy Javascript encryptor based on XOR algorithm? (html
page with encoded javascript will have a "decoder stub" prefixed before
the code that is actually executed.)

Undoubtedly. You can definitly pay for some, and there are probably also
some free versions floating around.

What you should ask yourself first is what you hope to achieve by
encoding. If it's security, then you should consider the threat model,
what you are trying to counter, including the likelyhood that the
deterrence will work and the cost if it fails.
I doubt there is any real gain to be had.

/L

 

[polychrom]

Lasse Reichstein Nielsen пиÑал(а):

(e-mail address removed) writes:

Is there some handy Javascript encryptor based on XOR algorithm? (html
page with encoded javascript will have a "decoder stub" prefixed
before
the code that is actually executed.)

 

[Matt Kruse]

well, what is some handy utility for encryption(obfuscation) without
any issues affecting on script functionality? Just make to difficult
reading if someone tries to explore source.

Well, read the FAQ or the 10,000 posts to this group in the archive
discussing this topic.

Obfuscation is a mostly pointless exercise. Most people who think they need
to obfuscate really don't. They just haven't figured that out yet.

 

[polychrom]

Matt Kruse пиÑал(а):

(e-mail address removed) wrote:
well, what is some handy utility for encryption(obfuscation) without
any issues affecting on script functionality? Just make to difficult
reading if someone tries to explore source.

----------------------------------------------------------------------------

Well, read the FAQ or the 10,000 posts to this group in the archive
discussing this topic.

Obfuscation is a mostly pointless exercise. Most people who think they need
to obfuscate really don't. They just haven't figured that out yet.

-----------------------------------------------------------
Amplification: I want find exact thing I need: XOR-based Javascript
encryptor.
(html page with encoded javascript will have a "decoder stub" prefixed
before
the code that is actually executed.) Simple and effective.

 

[Julian Turner]

Amplification: I want find exact thing I need: XOR-based Javascript
encryptor.
(html page with encoded javascript will have a "decoder stub" prefixed
before
the code that is actually executed.) Simple and effective.

In my amateur opinion, you are unlikely to find XOR based encryption,
because XOR could produce characters not recognised by the web page
encoding (e.g. control characters in the 0x80 to 0x9F range).

Also if the "decoder stub" is prefixed, in what sense is it encrypted?
It would only stop the most casual user. Any person who was interested
in seeing your source, would also have the capability to easily extract
the code using the decoder stub provided.

For simple method of compacting your JS files (with the side effect of
mild obfuscation), including a "decompacting stub", see:-

<URL:http://dean.edwards.name/packer/>

Regards

Julian Turner

 

[mistral]

Julian Turner пиÑал(а):

(e-mail address removed) wrote:

Amplification: I want find exact thing I need: XOR-based Javascript
encryptor.
(html page with encoded javascript will have a "decoder stub" prefixed
before the code that is actually executed.) Simple and effective.

In my amateur opinion, you are unlikely to find XOR based encryption,
because XOR could produce characters not recognised by the web page
encoding (e.g. control characters in the 0x80 to 0x9F range).

Also if the "decoder stub" is prefixed, in what sense is it encrypted?
It would only stop the most casual user. Any person who was interested
in seeing your source, would also have the capability to easily extract
the code using the decoder stub provided.

For simple method of compacting your JS files (with the side effect of
mild obfuscation), including a "decompacting stub", see:-


Julian Turner

--------------------------
yes, it is true objection for characters not recognised by the web page
encoding.
As to prefixed "decoder stub", this method is used for XOR encryption
in more advanced solutions, where is necessary encrypt C code (mainly
to prevent AV). However, any decryptor can be placed before the
encrypted code.

 

[Julian Turner]

As to prefixed "decoder stub", this method is used for XOR encryption
in more advanced solutions, where is necessary encrypt C code (mainly
to prevent AV). However, any decryptor can be placed before the
encrypted code.

Ahh, yes. With a bit of self-education, googling on "decode stub" gives
results in relation to:-

(a) Hiding viruses from Anti Virus software (as you say).

(b) Trying to hide/obfuscate .exe code in general. This seems to
receive the same treatment as hiding .js code. You can try, but there
are a lot of clever folks out there.

Regards

Julian Turner