two way encryption algorithm

[sj1187534]

Hi...Does anyone know any two-way encryption algoritm. I have been trying to use the DES and the TripleDES algorithms but the problem with these is I am not able to pass the encrypted string through the querystring as the encrypted string has some special characters in it. Any ideas?

 

For instance when I am trying to encrypt the number "126" using DES encryption method, the encrypted string is 'lng0+5+6Utk=' which cannot be passed through the querystring because of the '+' character. I dont know why!!

 

SJ

[PlausiblyDamp]

You could use the

system.Web.HttpUtility.HtmlEncode() and system.Web.HttpUtility.HtmlDecode() functions to make the string HTML safe and then convert it back again.

[sj1187534]

Hi...It is not working. For some reason, the character '+' in the encoded string is vanishing even when HttpUtility.HtmlDecode() is used on the encrypted string. Is there any significance for the '+' char in the querystring?

 

SJ

[Arch4ngel]

Maybe HtmlUrlEncode ?

[sj1187534]

Nope...Thats not working either!!

 

SJ

[Arch4ngel]

HttpUtility.UrlPathEncode(...) then ?

 

If it work... alright...everythings perfect

If it doesn't... try bashing your case with a hammer. I heard that it solve most of the problem "into" your computer. :D

 

If none of above work... you'll have to convert char from "+" to %343 (not the right value) you know ? Their ANSI value in integer. (Isn't it ?)

[sj1187534]

Hi..That is not working either. All the encoding and decoding is making the '+' character vanish!!! And I am having this problem for the '+' char alone. I have'nt come across anything else yet. So, I cannot write any code to replace the '+' char with whatever ascii value it has.

 

Do you know any two-way encryption algorithm that does not give any special characters in the encoded string. For ex: the MD5 and SHA1 encryption algorithms returns the encrypted strings in alphabets and numbers only. But both of them are one-way encryption algorithms!!

 

SJ

[Arch4ngel]

Encoding

 

Wasn't damn able to find a suitable function so I build ya one

 

[/color][/size][size=2][color=#0000ff]public[/color][/size][size=2][color=#0000ff]string[/color][/size][size=2] Encode([/size][size=2][color=#0000ff]string[/color][/size][size=2] str)[/size]
[size=2]{[/size]
[size=2][color=#0000ff]   string[/color][/size][size=2] ret = "";[/size]
[size=2]   System.Text.Encoding ascii = System.Text.Encoding.ASCII;[/size]
[size=2][color=#0000ff]   byte[/color][/size][size=2][] bs = ascii.GetBytes(str);[/size]
[size=2][color=#0000ff]   foreach[/color][/size][size=2]( [/size][size=2][color=#0000ff]byte[/color][/size][size=2] b [/size][size=2][color=#0000ff]in[/color][/size][size=2] bs)[/size]
[size=2]   {[/size]
[size=2]     ret += "&" + b + ";";[/size]
[size=2]   }[/size]
[size=2][color=#0000ff]   return[/color][/size][size=2] ret;[/size]
[size=2]}[/size][size=2]

 

That's it... they are now encoded... find a way now to deencode them :D

Other people want me you see what I mean :cool:

[sj1187534]

Hi...Thanks for the code. Infact, my code is working with a small change that I have made. Instead of using Server.URLEncode, I used HTTPUtility.URLEncode when passing the encrypted string into the URL like this:

 

"./sample.aspx?id=" & HttpUtility.UrlEncode(CryptoUtil.EncryptTripleDES(dr.Item("idnum")))

 

But when I am trying to read from the querystring, I am not using any HTTPUtility.URLDecode. Like this:

 

CInt(CryptoUtil.Decrypt(Request.QueryString("id")))

 

Everything is working great.

 

Thanks

SJ