/* check if nonce-count nc w/ index i is expected/valid and if so it
* updated the stored nonce-count
* returns: 0 - ok, < 0 some error:
* NC_INV_POOL (pool number is invalid/corrupted)
* NC_ID_OVERFLOW (crt_id has overflowed with partition size since the
* id was generated)
* NC_TOO_BIG (nc value got too big and cannot be held anymore)
* NC_REPLAY (nc value is <= the current stored one)
*/
enum nc_check_ret nc_check_val(nid_t id, unsigned pool, unsigned int nc)
{
unsigned int i;
unsigned n, r;
unsigned int v, crt_nc, new_v;
if (unlikely(pool>=nid_pool_no))
return NC_INV_POOL;
if (unlikely(nc_id_check_overflow(id, pool)))
return NC_ID_OVERFLOW;
if (unlikely(nc>=(1U<<(sizeof(nc_t)*8))))
return NC_TOO_BIG;
n=get_nc_array_raw_idx(id, pool); /* n-th nc_t */
i=get_nc_array_uint_idx(n); /* aray index i, corresponding to n */
r=get_nc_int_pos(n); /* byte/short inside the uint corresponding to n */
do{
v=atomic_get_int(&nc_array[i]);
/* get current (stored) nc value */
crt_nc=(v>>(r*8)) & ((1U<<(sizeof(nc_t)*8))-1);
if (crt_nc>=nc)
return NC_REPLAY;
/* set corresponding array cell byte/short to new nc */
new_v=(v & ~(((1U<<(sizeof(nc_t)*8))-1)<< (r*8)) )|
(nc << (r*8));
}while(atomic_cmpxchg_int((int*)&nc_array[i], v, new_v)!=v);
return 0;
}
/* check if nonce w/ index i is expected/valid and if so marked it "seen"
* returns: 0 - ok, < 0 some error:
* OTN_INV_POOL (pool number is invalid/corrupted)
* OTN_ID_OVERFLOW (crt_id has overflowed with partition size since the
* id was generated)
* OTN_REPLAY (nonce id seen before => replay )
*/
enum otn_check_ret otn_check_id(nid_t id, unsigned pool)
{
unsigned int i;
unsigned n, b;
otn_cell_t v, b_mask;
if (unlikely(pool>=nid_pool_no))
return OTN_INV_POOL;
if (unlikely(otn_id_check_overflow(id, pool)))
return OTN_ID_OVERFLOW;
n=get_otn_array_bit_idx(id, pool); /* n-th bit */
i=get_otn_array_cell_idx(n); /* aray index i, corresponding to n */
b=get_otn_cell_bit(n); /* bit pos corresponding to n */
b_mask= (otn_cell_t)1<<b;
#ifdef OTN_CELL_T_LONG
v=atomic_get_long(&oth_array[i]);
if (unlikely(v & b_mask))
return OTN_REPLAY;
atomic_or_long((long*)&otn_array[i], b_mask);
#else
v=atomic_get_int(&otn_array[i]);
if (unlikely(v & b_mask))
return OTN_REPLAY;
atomic_or_int((int*)&otn_array[i], b_mask);
#endif /* OTN_CELL_T_LONG */
return 0;
}
/* re-init the stored nc for nonce id in pool p */
nid_t nc_new(nid_t id, unsigned char p)
{
unsigned int i;
unsigned n, r;
unsigned int v, new_v;
n=get_nc_array_raw_idx(id, p); /* n-th nc_t */
i=get_nc_array_uint_idx(n); /* aray index i, corresponding to n */
r=get_nc_int_pos(n); /* byte/short inside the uint corresponding to n */
/* reset corresponding value to 0 */
do{
v=atomic_get_int(&nc_array[i]);
/* new_value = old_int with the corresponding byte or short zeroed*/
new_v=v & ~(((1<<(sizeof(nc_t)*8))-1)<< (r*8));
}while(atomic_cmpxchg_int((int*)&nc_array[i], v, new_v)!=v);
return id;
}
