Solved

OpenSSL with C++, 3DES Decrypt

Posted on 2012-12-28
3
2,670 Views
Last Modified: 2013-01-08
Hello Experts,

I have to create code to decrypt using OpenSSL 3DES in C++.

I decrypted my encrypted string with OpenSSL command line like followings,

echo -en "\xca\x99\x19\x61\xd1\x21\x4f......." |
openssl des3 -d
-K  e3c254b6ec976b4638f216c83de61504166d7.... -iv 4eed0d2f1c....

I have to create code those function in C++(DES_ncbc_encrypt()..etc).
I've already installed OpenSSL in my environment.

Windows 7 32bit, C++Builder

Please advice.
0
Comment
Question by:NobMiwa
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
3 Comments
 
LVL 64

Expert Comment

by:btan
ID: 38728842
0
 

Author Comment

by:NobMiwa
ID: 38729179
Thank you for information.

I coded followings..

	unsigned char key[] = {0xe3,0xc2,0x54,0xb6,0xec,0x97,0x6b,0x46,0x38,0xf2,0x16,0xc8,0x3d,0xe6,0x15,0x04,0x16,0x6d,0x70,0x70,0xae,0x97,0xbf,0xb6};

	unsigned char iv[]  = {0x4e,0xed,0x0d,0x2f,0x1c,0x48,0xe0,0xf1};
	unsigned char encrypted[] = {0xca,0x99,0x19,0x61,0xd1,0x21,0x4f,0x77,0x3e,0x0d,0xd3,0xcc,0x07,0x9f,0x56,0x24};

	const EVP_CIPHER* cipherType = EVP_des_ede3_ecb();
	EVP_CIPHER_CTX ctx;
	EVP_CIPHER_CTX_init(&ctx);
	int rt = EVP_DecryptInit(&ctx, (const EVP_CIPHER*)cipherType, (const unsigned char*)key, (const unsigned char*)iv);

	int out_len;
	char ciphertext[2048] = {0};
	memset(ciphertext, 0x00, sizeof(ciphertext));

	rt = EVP_DecryptUpdate(&ctx, (unsigned char*)ciphertext, &out_len, (const unsigned char*)encrypted, 16);
	rt = EVP_DecryptFinal(&ctx, (unsigned char*)ciphertext, &out_len);

	rt = EVP_CIPHER_CTX_cleanup(&ctx);

Open in new window


The answer must be "berobero", but I got 8 letters and was not the answer.

Please advice, if you have any idea..
0
 
LVL 64

Accepted Solution

by:
btan earned 500 total points
ID: 38729331
Was thinking an6thing to do with padding or the parameter to decrypt function

http://www.openssl.org/docs/crypto/EVP_EncryptInit.html

.

EVP_DecryptInit_ex(),EVP_DecryptUpdate() andEVP_DecryptFinal_ex() are the corresponding decryption operations.EVP_DecryptFinal() will return an error code if padding is enabled and the final block is not correctly formatted. The parameters and restrictions are identical to the encryption operations except that if padding is enabled the decrypted data buffer out passed toEVP_DecryptUpdate() should have sufficient room for (inl + cipher_block_size) bytes unless the cipher block size is 1 in which case inl bytes is sufficient.
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Healthcare providers, insurance companies and other covered entities trust eFax Corporate to transmit their most sensitive documents. eFax Corporate can help your organization implement a HIPAA compliant cloud faxing solution.
Businesses who process credit card payments have to adhere to PCI Compliance standards. Here’s why that’s important.
The viewer will learn how to clear a vector as well as how to detect empty vectors in C++.
The Email Laundry PDF encryption service allows companies to send confidential encrypted  emails to anybody. The PDF document can also contain attachments that are embedded in the encrypted PDF. The password is randomly generated by The Email Laundr…

726 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question