How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt. - C# Discussion Boards

Re: Form loses focus

fjdiewornncalwe15-Oct-10 4:32

fjdiewornncalwe

15-Oct-10 4:32

Thanks. It's ok though, because I expose my "utility" email address and not my primary one.

Re: Form loses focus

Luc Pattyn15-Oct-10 2:19

Luc Pattyn

15-Oct-10 2:19

Handling the problem by e-mail keeps other interested parties from seeing the solution to a problem. If it is too much for a forum post, you might consider writing a tip&trick or even an article about it.

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

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Re: Form loses focus

electriac15-Oct-10 2:35

electriac

15-Oct-10 2:35

Your right. I finally found the answer to the problem. The child form was not the problem. In the parent form I had done this:

this.WindowState = System.Windows.Forms.FormWindowState.Minimized;
Form2 dlg = new Form2(fname);
dlg.ShowDialog();

For some reason this causes Form2 to be inactive I know not why.

Re: Form loses focus

Luc Pattyn15-Oct-10 2:46

Luc Pattyn

15-Oct-10 2:46

The main form represents the entire app (when it closes, the app exits). I'm surprised the dialog was even showing, if you had minimized the main form later on, the dialog would have disappeared too (try right-clicking minimize on the task bar on any app).

BTW: these special things you just showed should have been mentioned earlier...

Cheers.

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

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Re: Form loses focus

fjdiewornncalwe15-Oct-10 4:36

fjdiewornncalwe

15-Oct-10 4:36

Agreed. I didn't even think to ask that yesterday. D'Oh! | :doh:

Re: Form loses focus

fjdiewornncalwe15-Oct-10 4:33

fjdiewornncalwe

15-Oct-10 4:33

Hey Luc,

Rather than span the forum with numerous posts along the way, the idea was to figure out what was wrong and then post that, not the entire process of getting there.

Cheers Smile | :)

Re: Form loses focus

Paw Jershauge15-Oct-10 1:38

Paw Jershauge

15-Oct-10 1:38

Have you considered using the ProcessCmdKey overload or event ??? instead of keypress event

With great code, comes great complexity, so keep it simple stupid... $Shucks | :-\$ $Shucks | :-\$

How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt.

Ongcos14-Oct-10 7:04

Ongcos

14-Oct-10 7:04

Hello everybody,
I don't know if here is the right section, if not, please change.

I need some support with this questions.
I will present here my problem:

Suppose I want a software to give to someone to encrypt text, and to encrypt the program should use the privatekey ( that only I know, but the program will need to encrypt data, so it must be hidden there) and to decrypt it should use the public key, that I can give to anyone.

So, now:

I have a private key and a public key, generated by open ssl: privatekey.pem and publickey.pem

Now, I need to be able to use those keys to encrypt and decrypt data.
the thing is, how I load the .pem to the program?
As I readed I need to load it to rsaparameters, but how I do it?

The type of the keys are:
-----BEGIN RSA PRIVATE KEY-----
MIICXQIBAAKB...

and
-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBA...

Any help would be very usefull, since I'm having a lot of troubles making it.

Re: How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt.

Alegria_Lee14-Oct-10 21:05

Alegria_Lee

14-Oct-10 21:05

here is an example.
http://wenku.baidu.com/view/87cbefaedd3383c4bb4cd2ac.html[^]

Re: How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt.

Ongcos14-Oct-10 22:21

Ongcos

14-Oct-10 22:21

Alegria_Lee Thanks a lot!

I will study this example today, and try to solve my problem. But this seams really helpfull.
I'll post here if I get it working or not. If you dont mind, stay checking here. Smile | :)

Re: How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt. [modified]

Ongcos15-Oct-10 2:05

Ongcos

15-Oct-10 2:05

Ok, It helped me a lot. Now I'm able to use my own private/public keys. Without any problem Smile | :)

Now, the thing is:

I need to encrypt the data using the private key.
And I need to decrypt it using the public key.

But RSA dont let me... I can encrypt with the private key, but them, I cant decript with the public one.

modified on Friday, October 15, 2010 9:46 AM

Re: How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt.

Alegria_Lee15-Oct-10 3:06

Alegria_Lee

15-Oct-10 3:06

I'm glad it's helpfull for you.
Actually,I haven't used this before. Big Grin | :-D

Re: How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt.

Ongcos17-Oct-10 22:51

Ongcos

17-Oct-10 22:51

well, but is good and is working Wink | ;)

thank you a lot.

Re: How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt.

Alegria_Lee18-Oct-10 4:34

Alegria_Lee

18-Oct-10 4:34

You're welcome.
By the way,Have you find out a solution to solved your problem ?(" encrypt with private key and decrypt with public key ")
AS i know,RSA can not seem to do so .

Re: How to put a rsa private key "hiden" in the code, and encrypt something with RSA! Sending the public key to decrypt.

Ongcos7-Nov-10 22:23

Ongcos

7-Nov-10 22:23

yes, is not possible.
But I noticed that what I wanted it could be made with the method: signdata
It signs data with private key and unsign with public key =)

getPixel problem c#

badescuga14-Oct-10 6:55

badescuga

14-Oct-10 6:55

Hello!
I have a problem with getting the pixels from an image. I load a image, select a pixel from the image and retrieve it's color and then i generate a matrix indexMatrix[bitmap_height][bitmap_width] which contains 1 or 0 depending if the [x,y] color of the bitmap is the same as the color selected. The problem is that the program doesn't select all the pixels although it should. Here are some images of the bitmap and the bitmap generated from the matrix :

original:
http://img233.imageshack.us/i/hartap.jpg/
after matrix generation and the transform from the matrix to the new image
http://img826.imageshack.us/i/60079199.jpg

The wierd thing is that if i run my program for the new image ( the one constructed from the matrix ) it returns the same image( as it should ) but i can't figure out how to fix the problem.

Please Help!!!

Regards,
Alex Badescu
and some code from my project :

bitmap declaration:

m_Bitmap = (Bitmap)Bitmap.FromFile(openFileDialog.FileName, false);

Here i calculate the matrix:

int bitmapWidth = m_Bitmap.Width;
int bitmapHeight = m_Bitmap.Height;

indexMatrix = new int[bitmapHeight][];

if (imageIsLoaded && colorIsSelected)
{
for (int i = 0; i < bitmapHeight; i++)
{
indexMatrix[i] = new int[bitmapWidth];

for (int j = 0; j < bitmapWidth; j++)
{
Color temp = m_Bitmap.GetPixel(j, i);
if (temp == selectedColor)
indexMatrix[i][j] = 1;
else indexMatrix[i][j] = 0;

}
}
MessageBox.Show("matrix generated succesfully");
}
matrixIsCalculated = true;
}

Re: getPixel problem c#

Rick Shaub14-Oct-10 7:11

Rick Shaub

14-Oct-10 7:11

Try using Color.ToArgb() method for the comparisons. ie,

if(temp.ToArgb()  == selectedColor.ToArgb())<br />

The equality operator uses some state flags for the comparison in addition to the ARGB values.

Re: getPixel problem c#

badescuga14-Oct-10 7:20

badescuga

14-Oct-10 7:20

it still doesn't work..

Re: getPixel problem c#

Luc Pattyn14-Oct-10 7:31

Luc Pattyn

14-Oct-10 7:31

I'm afraid there is a fundamental flaw in your approach: JPEG images tend to be highly compressed, which means every pixel is approximated in such a way that fewer bits are required. Applying an equal-test on jpegged images does not make much sense. What you should do is allow for some deviation, say:

deviation=deltaRed*deltaRed+deltaGreen*deltaGreen+deltaBlue*deltaBlue

or similar in another color space (e.g. HSB).
Only when the deviation is large enough you should call the pixel "not blue".

BTW: why don't you use a normal 2D matrix, as in int[bitmapWidth, bitmapHeight]?

Smile | :)

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Refresh User Control look

Mazdak14-Oct-10 3:17

Mazdak

14-Oct-10 3:17

I have custom windows user control. It is just a textbox puted on a panel. And panel is on User control. The panel OnPaint is overriden.

Everything looks fine except when some form comes on the control or menu open on it and I move or close the above form, the user control looks does not refresh completely extra lines from closed form remain on the panel. Should I call Invalidate() or Refresh() from specific event of user control?

Thanks

Mazy

"This chancy chancy chancy world."

Re: Refresh User Control look

Luc Pattyn14-Oct-10 3:35

Luc Pattyn

14-Oct-10 3:35

does your Paint handler contain a base.OnPaint()?

Smile | :)

Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles] Nil Volentibus Arduum

Please use <PRE> tags for code snippets, they preserve indentation, and improve readability.

Convert color from RGB to Color name

MrKBA14-Oct-10 0:22

MrKBA

14-Oct-10 0:22

Hello,

I use a ColorEdit control in my form ( as picture )
I need to analyse the case when the user choose a color from Custom tab which the color is represtend in RGB structure as I know Hmmm | :|

the problem that i need to translate this value (ie 245;245;220) to the color name (ie "beige") that i can save it after to use an other time by methode Color.FromName(name)

please can someone help me.
thank you

http://yfrog.com/63clipboard01kg[^]

Re: Convert color from RGB to Color name

V.14-Oct-10 0:52

14-Oct-10 0:52

You can use the FromArgb method and pass it the integer values. That would make converting it obsolete. Not all values can be converted to a name either so converting would mean omitting many possibilities.

Re: Convert color from RGB to Color name

MrKBA14-Oct-10 1:27

MrKBA

14-Oct-10 1:27

So when its unknown color (ie its choosed in custom tab and not exist in the array of known colors)
how can i get its name?

Re: Convert color from RGB to Color name

V.14-Oct-10 1:35

14-Oct-10 1:35

That's the thing, you can't. You should save it's RGB values, not the name.

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