#include "gsskrb5_locl.h"
#define DEFAULT_JITTER_WINDOW 20
#define MAX_JITTER_WINDOW 10000
struct gss_msg_order {
OM_uint32 flags;
OM_uint32 start;
OM_uint32 length;
OM_uint32 jitter_window;
OM_uint32 first_seq;
OM_uint32 elem[1];
};
static OM_uint32
msg_order_alloc(OM_uint32 *minor_status,
struct gss_msg_order **o,
OM_uint32 jitter_window)
{
size_t len;
len = jitter_window * sizeof((*o)->elem[0]);
len += sizeof(**o);
len -= sizeof((*o)->elem[0]);
*o = calloc(1, len);
if (*o == NULL) {
*minor_status = ENOMEM;
return GSS_S_FAILURE;
}
*minor_status = 0;
return GSS_S_COMPLETE;
}
OM_uint32
_gssapi_msg_order_create(OM_uint32 *minor_status,
struct gss_msg_order **o,
OM_uint32 flags,
OM_uint32 seq_num,
OM_uint32 jitter_window,
int use_64)
{
OM_uint32 ret;
if (jitter_window == 0)
jitter_window = DEFAULT_JITTER_WINDOW;
ret = msg_order_alloc(minor_status, o, jitter_window);
if(ret != GSS_S_COMPLETE)
return ret;
(*o)->flags = flags;
(*o)->length = 0;
(*o)->first_seq = seq_num;
(*o)->jitter_window = jitter_window;
(*o)->elem[0] = seq_num - 1;
*minor_status = 0;
return GSS_S_COMPLETE;
}
OM_uint32
_gssapi_msg_order_destroy(struct gss_msg_order **m)
{
free(*m);
*m = NULL;
return GSS_S_COMPLETE;
}
static void
elem_set(struct gss_msg_order *o, size_t slot, OM_uint32 val)
{
o->elem[slot % o->jitter_window] = val;
}
static void
elem_insert(struct gss_msg_order *o,
size_t after_slot,
OM_uint32 seq_num)
{
assert(o->jitter_window > after_slot);
if (o->length > after_slot)
memmove(&o->elem[after_slot + 1], &o->elem[after_slot],
(o->length - after_slot - 1) * sizeof(o->elem[0]));
elem_set(o, after_slot, seq_num);
if (o->length < o->jitter_window)
o->length++;
}
OM_uint32
_gssapi_msg_order_check(struct gss_msg_order *o, OM_uint32 seq_num)
{
OM_uint32 r;
size_t i;
if (o == NULL)
return GSS_S_COMPLETE;
if ((o->flags & (GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG)) == 0)
return GSS_S_COMPLETE;
if (o->elem[0] == seq_num - 1) {
elem_insert(o, 0, seq_num);
return GSS_S_COMPLETE;
}
r = (o->flags & (GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG))==GSS_C_REPLAY_FLAG;
if (seq_num > o->elem[0]
|| seq_num < o->first_seq
|| o->length == 0)
{
elem_insert(o, 0, seq_num);
if (r) {
return GSS_S_COMPLETE;
} else {
return GSS_S_GAP_TOKEN;
}
}
assert(o->length > 0);
if (seq_num < o->elem[o->length - 1]) {
if (r)
return(GSS_S_OLD_TOKEN);
else
return(GSS_S_UNSEQ_TOKEN);
}
if (seq_num == o->elem[o->length - 1]) {
return GSS_S_DUPLICATE_TOKEN;
}
for (i = 0; i < o->length - 1; i++) {
if (o->elem[i] == seq_num)
return GSS_S_DUPLICATE_TOKEN;
if (o->elem[i + 1] < seq_num && o->elem[i] < seq_num) {
elem_insert(o, i, seq_num);
if (r)
return GSS_S_COMPLETE;
else
return GSS_S_UNSEQ_TOKEN;
}
}
return GSS_S_FAILURE;
}
OM_uint32
_gssapi_msg_order_f(OM_uint32 flags)
{
return flags & (GSS_C_SEQUENCE_FLAG|GSS_C_REPLAY_FLAG);
}
krb5_error_code
_gssapi_msg_order_export(krb5_storage *sp, struct gss_msg_order *o)
{
krb5_error_code kret;
OM_uint32 i;
kret = krb5_store_int32(sp, o->flags);
if (kret)
return kret;
kret = krb5_store_int32(sp, o->start);
if (kret)
return kret;
kret = krb5_store_int32(sp, o->length);
if (kret)
return kret;
kret = krb5_store_int32(sp, o->jitter_window);
if (kret)
return kret;
kret = krb5_store_int32(sp, o->first_seq);
if (kret)
return kret;
for (i = 0; i < o->jitter_window; i++) {
kret = krb5_store_int32(sp, o->elem[i]);
if (kret)
return kret;
}
return 0;
}
OM_uint32
_gssapi_msg_order_import(OM_uint32 *minor_status,
krb5_storage *sp,
struct gss_msg_order **o)
{
OM_uint32 ret;
krb5_error_code kret;
int32_t i, flags, start, length, jitter_window, first_seq;
kret = krb5_ret_int32(sp, &flags);
if (kret)
goto failed;
kret = krb5_ret_int32(sp, &start);
if (kret)
goto failed;
kret = krb5_ret_int32(sp, &length);
if (kret)
goto failed;
kret = krb5_ret_int32(sp, &jitter_window);
if (kret)
goto failed;
kret = krb5_ret_int32(sp, &first_seq);
if (kret)
goto failed;
if (jitter_window < 0 || jitter_window > MAX_JITTER_WINDOW) {
kret = EINVAL;
goto failed;
}
ret = msg_order_alloc(minor_status, o, jitter_window);
if (ret != GSS_S_COMPLETE)
return ret;
(*o)->flags = flags;
(*o)->start = start;
(*o)->length = length;
(*o)->jitter_window = jitter_window;
(*o)->first_seq = first_seq;
for( i = 0; i < jitter_window; i++ ) {
kret = krb5_ret_int32(sp, (int32_t*)&((*o)->elem[i]));
if (kret)
goto failed;
}
*minor_status = 0;
return GSS_S_COMPLETE;
failed:
_gssapi_msg_order_destroy(o);
if (minor_status)
*minor_status = kret;
return GSS_S_FAILURE;
}