SSL-simple of RSA

RSA is an asymmetric encryption algorithm.

Features:
Encryption and decryption use a completely different and completely matched pair of public and private keys

-- RSA key generation
RSA * rsa_generate_key (INT bits, unsigned long e, void (* callback) (INT, Int, void *), void * cb_arg );

-- RSA encryption and decryption
Int rsa_public_encrypt (int flen, const unsigned char * From, unsigned char * To, RSA * RSA, int padding );
Int rsa_private_decrypt (int flen, const unsigned char * From, unsigned char * To, RSA * RSA, int padding );

-- RSA signature and Verification
The RSA signature operation uses the private key to encrypt the hash value of the signed message.
Int rsa_sign (INT type, const unsigned char * m, unsigned int m_length, unsigned char * sigret, unsigned int * siglen, RSA * RSA );
Int rsa_verify (INT type, const unsigned char * m, unsigned int m_length, unsigned char * sigbuf, unsigned int siglen, RSA * RSA );

/** <Br/> * Open SSL guide <br/> * http://www.openssl.org/docs/crypto//rsa.html <br/> */<br/> # include <strings. h> <br/> # include <OpenSSL/RSA. h> <br/> # include <OpenSSL/err. h> <br/> // # define rsa_f4 0x10001l/65537 <br/> # define modulus "c8fbcf21" <br/> # define public_exponent rsa_f4 <br/> # define private_exponent" 97b55d7d "<br/> RSA * my_generate_key () <br/>{< br/> bignum * BNN, * BNE, * BND; <br/> BNN = Bn_new (); <br/> BNE = bn_new (); <br/> BND = bn_new (); <br/> bn_hex2bn (& BNN, modulus ); <br/> bn_set_word (BNE, public_exponent); <br/> bn_hex2bn (& BND, private_exponent); <br/> RSA * r = rsa_new (); <br/> r-> N = BNN; <br/> r-> E = BNE; <br/> r-> d = BND; <br/> return R; <br/>}< br/> int main () <br/>{< br/> int ret, FLEN; <br/> unsigned char * cleartext = (unsigned char *) "text"; <br/> unsigned char * Cipher Text; <br/> // RSA * r = my_generate_key (); <br/> // RSA * r = rsa_generate_key (512, rsa_f4, null, null ); <br/> RSA * r = rsa_generate_key (1024, rsa_f4, null, null); <br/> // RSA * r_public = rsapublickey_dup (R ); <br/> // RSA * r_private = rsw.vatekey_dup (r); <br/> FLEN = rsa_size (r); <br/> rsa_print_fp (stdout, R, FLEN ); <br/> ciphertext = (unsigned char *) malloc (FLEN); <br/> bzero (ciphertext, FLEN); <br/> P Rintf ("begin encrypt... /n "); <br/> ret = rsa_public_encrypt (FLEN, cleartext, ciphertext, R, rsa_no_padding); <br/> If (Ret <0) <br/>{< br/> printf ("encrypt failed! "); <Br/> return 1; <br/>}< br/> printf (" Size: % d/N ", RET ); <br/> printf ("cleartext: % s/n", cleartext); <br/> printf ("ciphertext :"); <br/> for (INT I = 0; I <ret; I ++) <br/> {<br/> printf ("% 02x ", ciphertext [I]); <br/>}< br/> printf ("/N"); </P> <p> printf ("/nbegin decrypt... /n "); <br/> ret = rsa_private_decrypt (FLEN, ciphertext, cleartext, R, rsa_no_padding); <br/> If (Ret <0) <br/> {<br/> printf ("d Ecrypt failed! "); <Br/> return 1; <br/>}< br/> printf (" Size: % d/N ", RET ); <br/> printf ("cleartext: % s/n", cleartext); <br/> printf ("ciphertext :"); <br/> for (INT I = 0; I <ret; I ++) <br/> {<br/> printf ("% 02x ", ciphertext [I]); <br/>}< br/> printf ("/N"); <br/> free (ciphertext ); <br/> rsa_free (r); <br/> return 0; <br/>}< br/>