/*
* Given a hex encoded string, decode it into a chunk.
*
* If this function fails, crash and burn. It is fed static data
* so should never ever have a problem.
* The caller must free the chunk.
*/
chunk_t decode_hex_to_chunk(const char *original, const char *string)
{
/* The decoded buffer can't be bigger than half the encoded string. */
chunk_t chunk = zalloc_chunk((strlen(string)+1)/2, original);
chunk.len = 0;
const char *pos = string;
for (;;) {
/* skip leading/trailing space */
while (*pos == ' ') {
pos++;
}
if (*pos == '\0') {
break;
}
/* Expecting <HEX><HEX> */
char buf[3] = { '\0', '\0', '\0' };
if (isxdigit(*pos)) {
buf[0] = *pos++;
if (isxdigit(*pos)) {
buf[1] = *pos++;
}
}
if (buf[1] == '\0') {
PASSERT_FAIL("expected hex digit at offset %tu in hex buffer \"%s\" but found \"%.1s\"",
pos - string, string, pos);
}
char *end;
chunk.ptr[chunk.len] = strtoul(buf, &end, 16);
passert(*end == '\0');
chunk.len++;
}
return chunk;
}
static void nss_ecp_calc_secret(const struct dh_desc *group,
SECKEYPrivateKey **privk,
SECKEYPublicKey **pubk,
uint8_t *ke, size_t sizeof_ke)
{
passert(sizeof_ke == group->bytes);
/*
* Get the PK11 formatted EC parameters (stored in static
* data) from NSS.
*/
DBG(DBG_CRYPT, DBG_log("oid %d %x", group->nss_oid, group->nss_oid));
SECOidData *pk11_data = SECOID_FindOIDByTag(group->nss_oid);
if (pk11_data == NULL) {
PASSERT_FAIL("Lookup of OID %d for EC group %s parameters failed",
group->nss_oid, group->common.name);
}
LSWDBGP(DBG_CRYPT, buf) {
lswlogs(buf, "pk11_data->oid: ");
lswlog_nss_secitem(buf, &pk11_data->oid);
}
static void ike_alg_nss_cbc(const struct encrypt_desc *alg,
u_int8_t *in_buf, size_t in_buf_len, PK11SymKey *symkey,
u_int8_t *iv, bool enc)
{
DBG(DBG_CRYPT, DBG_log("NSS ike_alg_nss_cbc: %s - enter", alg->common.name));
if (symkey == NULL) {
PASSERT_FAIL("%s - NSS derived enc key in NULL",
alg->common.name);
}
SECItem ivitem;
ivitem.type = siBuffer;
ivitem.data = iv;
ivitem.len = alg->enc_blocksize;
SECItem *secparam = PK11_ParamFromIV(alg->common.nss_mechanism, &ivitem);
if (secparam == NULL) {
PASSERT_FAIL("%s - Failure to set up PKCS11 param (err %d)",
alg->common.name, PR_GetError());
}
PK11Context *enccontext;
enccontext = PK11_CreateContextBySymKey(alg->common.nss_mechanism,
enc ? CKA_ENCRYPT : CKA_DECRYPT,
symkey, secparam);
if (enccontext == NULL) {
PASSERT_FAIL("%s - PKCS11 context creation failure (err %d)",
alg->common.name, PR_GetError());
}
/* Output buffer for transformed data. */
u_int8_t *out_buf = PR_Malloc((PRUint32)in_buf_len);
int out_buf_len = 0;
SECStatus rv = PK11_CipherOp(enccontext, out_buf, &out_buf_len, in_buf_len,
in_buf, in_buf_len);
if (rv != SECSuccess) {
PASSERT_FAIL("%s - PKCS11 operation failure (err %d)",
alg->common.name, PR_GetError());
}
PK11_DestroyContext(enccontext, PR_TRUE);
/*
* Update the IV ready for the next call to this function.
*/
u_int8_t *new_iv;
if (enc) {
/*
* The IV for the next encryption call is the last
* block of encrypted output data.
*/
new_iv = out_buf + out_buf_len - alg->enc_blocksize;
} else {
/*
* The IV for the next decryption call is the last
* block of the encrypted input data.
*/
new_iv = in_buf + in_buf_len - alg->enc_blocksize;
}
memcpy(iv, new_iv, alg->enc_blocksize);
/*
* Finally, copy the transformed data back to the buffer. Do
* this after extracting the IV.
*/
memcpy(in_buf, out_buf, in_buf_len);
PR_Free(out_buf);
if (secparam != NULL)
SECITEM_FreeItem(secparam, PR_TRUE);
DBG(DBG_CRYPT, DBG_log("NSS ike_alg_nss_cbc: %s - exit", alg->common.name));
}
