CC_INLINE
int ccCoreZP2pointerAndData(size_t n, const cc_unit *source, uint8_t *dest, size_t *destLen)
{
size_t len;
if((len = ccn_write_uint_size(n, source)) > *destLen) {
return -1;
}
*destLen = len;
ccn_write_uint(n, source, *destLen, dest);
return 0;
}
static inline
CCCryptorStatus ccn_write_arg(size_t n, const cc_unit *source, uint8_t *dest, size_t *destLen)
{
size_t len;
if((len = ccn_write_uint_size(n, source)) > *destLen) {
return kCCMemoryFailure;
}
*destLen = len;
ccn_write_uint(n, source, *destLen, dest);
return kCCSuccess;
}
int
ccec_get_fullkey_components(ccec_full_ctx_t key, size_t *nbits,
uint8_t *x, size_t *xsize,
uint8_t *y, size_t *ysize,
uint8_t *d, size_t *dsize)
{
cc_size n = ccec_ctx_n(key);
size_t len;
if(ccec_get_pubkey_components(key, nbits, x, xsize, y, ysize)) return -1;
if((len = ccn_write_uint_size(n, ccec_ctx_k(key))) > *dsize) return -1;
*dsize = len;
ccn_write_uint(n, ccec_ctx_k(key), *dsize, d);
return 0;
}
CFDataRef SecKeyCopyExponent(SecKeyRef key) {
ccrsa_pub_ctx_t pubkey;
pubkey.pub = key->key;
size_t e_size = ccn_write_uint_size(ccrsa_ctx_n(pubkey), ccrsa_ctx_e(pubkey));
CFAllocatorRef allocator = CFGetAllocator(key);
CFMutableDataRef exponentData = CFDataCreateMutable(allocator, e_size);
if (exponentData == NULL)
return NULL;
CFDataSetLength(exponentData, e_size);
ccn_write_uint(ccrsa_ctx_n(pubkey), ccrsa_ctx_m(pubkey), e_size, CFDataGetMutableBytePtr(exponentData));
return exponentData;
}
CFDataRef SecKeyCopyModulus(SecKeyRef key) {
ccrsa_pub_ctx_t pubkey;
pubkey.pub = key->key;
size_t m_size = ccn_write_uint_size(ccrsa_ctx_n(pubkey), ccrsa_ctx_m(pubkey));
CFAllocatorRef allocator = CFGetAllocator(key);
CFMutableDataRef modulusData = CFDataCreateMutable(allocator, m_size);
if (modulusData == NULL)
return NULL;
CFDataSetLength(modulusData, m_size);
ccn_write_uint(ccrsa_ctx_n(pubkey), ccrsa_ctx_m(pubkey), m_size, CFDataGetMutableBytePtr(modulusData));
return modulusData;
}
OSStatus SecDHGenerateKeypair(SecDHContext dh, uint8_t *pub_key,
size_t *pub_key_len)
{
int result;
ccdh_gp_t gp = SecDH_gp(dh);
ccdh_full_ctx_t priv = SecDH_priv(dh);
if((result = ccdh_generate_key(gp, &dhrng, priv)))
return result;
/* output y as a big endian byte buffer */
size_t ylen = ccn_write_uint_size(ccdh_gp_n(gp), ccdh_ctx_y(priv));
if(*pub_key_len < ylen)
return errSecBufferTooSmall;
ccn_write_uint(ccdh_gp_n(gp),ccdh_ctx_y(priv), ylen, pub_key);
*pub_key_len = ylen;
return errSecSuccess;
}
OSStatus SecDHComputeKey(SecDHContext dh,
const uint8_t *pub_key, size_t pub_key_len,
uint8_t *computed_key, size_t *computed_key_len)
{
ccdh_gp_t gp = SecDH_gp(dh);
ccdh_full_ctx_t priv = SecDH_priv(dh);
ccdh_pub_ctx_decl_gp(gp, pub);
cc_size n = ccdh_gp_n(gp);
cc_unit r[n];
if(ccdh_import_pub(gp, pub_key_len, pub_key, pub))
return errSecInvalidKey;
if(ccdh_compute_key(priv, pub, r))
return errSecInvalidKey;
ccn_write_uint(n, r, *computed_key_len, computed_key);
size_t out_size = ccn_write_uint_size(n, r);
if(out_size < *computed_key_len)
*computed_key_len=out_size;
return errSecSuccess;
}
