RE: Error Encrytping Symmetric key with RSA Public Key
The answer is in: data too large for key size According to Secure Programming Cookbook, when using RSA PKCS #1 v1.5 padding you can only encrypt messages up to 11 bytes smaller than the modulus size in bytes. If you are using RSA-1024, then that is (1024/8)-11=117 bytes. Bill -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of William Estrada Sent: September 30, 2008 4:31 PM To: openssl-users@openssl.org Subject: Error Encrytping Symmetric key with RSA Public Key Hi group, I have written a simple program to test my understanding of the OpenSSL APIs. And of course I have a problem with one of them. My problem is that when I use RSA_public_encrypt to encrypt my Symmetric key is get the following error: Testing RSA encryption of Symmertic key 145 Encrypt In bytes: 128, 149 Encript failed: Code: 67555438 error:0406D06E rsa routines:RSA_padding_add_PKCS1_type_2 data too large for key size The program first generates a Symmetric key, then uses it to encrypt and decrypt some simple text that the user inputs. Next it create an RSA Key and a public RSA key. then the same with these keys. The last thing tested is the encryption of the Symmetric Key using the RSA keys which fails. The error message does not make any sense to me since the Sym key is only 128 bytes. I would appreciate any help with my problem. All of the code is here: http://64.124.13.3/_OpenSSL_/Keys/ Thanks for your time. -- William Estrada [EMAIL PROTECTED] Mt-Umunhum-Wireless.net ( http://Mt-Umunhum-Wireless.net ) Ymessenger: MrUmunhum __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager [EMAIL PROTECTED] __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager [EMAIL PROTECTED]
Re: Error Encrytping Symmetric key with RSA Public Key
Bill, You are 100% right. I increased my buffer from 1024 to 1115 and it works fine now. I guess I should RTFM more? Thanks. Bill Colvin wrote: The answer is in: data too large for key size According to Secure Programming Cookbook, when using RSA PKCS #1 v1.5 padding you can only encrypt messages up to 11 bytes smaller than the modulus size in bytes. If you are using RSA-1024, then that is (1024/8)-11=117 bytes. Bill -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of William Estrada Sent: September 30, 2008 4:31 PM To: openssl-users@openssl.org Subject: Error Encrytping Symmetric key with RSA Public Key Hi group, I have written a simple program to test my understanding of the OpenSSL APIs. And of course I have a problem with one of them. My problem is that when I use RSA_public_encrypt to encrypt my Symmetric key is get the following error: Testing RSA encryption of Symmertic key 145 Encrypt In bytes: 128, 149 Encript failed: Code: 67555438 error:0406D06E rsa routines:RSA_padding_add_PKCS1_type_2 data too large for key size The program first generates a Symmetric key, then uses it to encrypt and decrypt some simple text that the user inputs. Next it create an RSA Key and a public RSA key. then the same with these keys. The last thing tested is the encryption of the Symmetric Key using the RSA keys which fails. The error message does not make any sense to me since the Sym key is only 128 bytes. I would appreciate any help with my problem. All of the code is here: http://64.124.13.3/_OpenSSL_/Keys/ Thanks for your time. -- William Estrada [EMAIL PROTECTED] Mt-Umunhum-Wireless.net ( http://Mt-Umunhum-Wireless.net ) Ymessenger: MrUmunhum __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager [EMAIL PROTECTED]
