/**
\ingroup HighLevel_KeyGenerate
\brief Generates an RSA keypair
\param numbits Modulus size
\param e Public Exponent
\param keydata Pointer to keydata struct to hold new key
\return ops_true if key generated successfully; otherwise ops_false
\note It is the caller's responsibility to call ops_keydata_free(keydata)
*/
ops_boolean_t ops_rsa_generate_keypair(const int numbits, const unsigned long e,
ops_keydata_t* keydata)
{
ops_secret_key_t *skey=NULL;
RSA *rsa=RSA_new();
BN_CTX *ctx=BN_CTX_new();
BIGNUM *ebn=BN_new();
ops_keydata_init(keydata,OPS_PTAG_CT_SECRET_KEY);
skey=ops_get_writable_secret_key_from_data(keydata);
// generate the key pair
BN_set_word(ebn,e);
RSA_generate_key_ex(rsa,numbits,ebn,NULL);
// populate ops key from ssl key
skey->public_key.version=4;
skey->public_key.creation_time=time(NULL);
skey->public_key.days_valid=0;
skey->public_key.algorithm= OPS_PKA_RSA;
skey->public_key.key.rsa.n=BN_dup(rsa->n);
skey->public_key.key.rsa.e=BN_dup(rsa->e);
skey->s2k_usage=OPS_S2KU_ENCRYPTED_AND_HASHED;
skey->s2k_specifier=OPS_S2KS_SALTED;
//skey->s2k_specifier=OPS_S2KS_SIMPLE;
skey->algorithm=OPS_SA_CAST5; // \todo make param
skey->hash_algorithm=OPS_HASH_SHA1; // \todo make param
skey->octet_count=0;
skey->checksum=0;
skey->key.rsa.d=BN_dup(rsa->d);
skey->key.rsa.p=BN_dup(rsa->p);
skey->key.rsa.q=BN_dup(rsa->q);
skey->key.rsa.u=BN_mod_inverse(NULL,rsa->p, rsa->q, ctx);
assert(skey->key.rsa.u);
BN_CTX_free(ctx);
RSA_free(rsa);
ops_keyid(keydata->key_id, &keydata->key.skey.public_key);
ops_fingerprint(&keydata->fingerprint, &keydata->key.skey.public_key);
// Generate checksum
ops_create_info_t *cinfo=NULL;
ops_memory_t *mem=NULL;
ops_setup_memory_write(&cinfo, &mem, 128);
ops_push_skey_checksum_writer(cinfo, skey);
switch(skey->public_key.algorithm)
{
// case OPS_PKA_DSA:
// return ops_write_mpi(key->key.dsa.x,info);
case OPS_PKA_RSA:
case OPS_PKA_RSA_ENCRYPT_ONLY:
case OPS_PKA_RSA_SIGN_ONLY:
if(!ops_write_mpi(skey->key.rsa.d,cinfo)
|| !ops_write_mpi(skey->key.rsa.p,cinfo)
|| !ops_write_mpi(skey->key.rsa.q,cinfo)
|| !ops_write_mpi(skey->key.rsa.u,cinfo))
return ops_false;
break;
// case OPS_PKA_ELGAMAL:
// return ops_write_mpi(key->key.elgamal.x,info);
default:
assert(0);
break;
}
// close rather than pop, since its the only one on the stack
ops_writer_close(cinfo);
ops_teardown_memory_write(cinfo, mem);
// should now have checksum in skey struct
// test
if (debug)
test_secret_key(skey);
return ops_true;
}
ops_boolean_t ops_decrypt_memory(const unsigned char *encrypted_memory,int em_length,
unsigned char **decrypted_memory,int *out_length,
ops_keyring_t* keyring,
const ops_boolean_t use_armour,
ops_parse_cb_t* cb_get_passphrase)
{
int fd_in=0;
int fd_out=0;
char* myfilename=NULL;
//
ops_parse_info_t *pinfo=NULL;
// setup for reading from given input file
ops_memory_t *input_mem = ops_memory_new() ;
ops_memory_add(input_mem,encrypted_memory,em_length) ;
ops_setup_memory_read(&pinfo, input_mem, NULL, callback_write_parsed, ops_false);
if (pinfo == NULL)
{
perror("cannot create memory read");
return ops_false;
}
// setup memory chunk
ops_memory_t *output_mem;
ops_setup_memory_write(&pinfo->cbinfo.cinfo, &output_mem,0) ;
if (output_mem == NULL)
{
perror("Cannot create output memory");
ops_teardown_memory_read(pinfo, input_mem);
return ops_false;
}
// \todo check for suffix matching armour param
// setup keyring and passphrase callback
pinfo->cbinfo.cryptinfo.keyring=keyring;
pinfo->cbinfo.cryptinfo.cb_get_passphrase=cb_get_passphrase;
// Set up armour/passphrase options
if (use_armour)
ops_reader_push_dearmour(pinfo);
// Do it
ops_boolean_t res = ops_parse_and_print_errors(pinfo);
// Unsetup
if (use_armour)
ops_reader_pop_dearmour(pinfo);
// copy output memory to supplied buffer.
//
*out_length = ops_memory_get_length(output_mem) ;
*decrypted_memory = ops_mallocz(*out_length) ;
memcpy(*decrypted_memory,ops_memory_get_data(output_mem),*out_length) ;
ops_decrypt_memory_ABORT:
ops_teardown_memory_write(pinfo->cbinfo.cinfo, output_mem);
ops_teardown_memory_read(pinfo, input_mem);
return res ;
}
