cfg80211: simplify mesh BSS comparison

Instead of first checking if a BSS is an MBSS
and then doing the comparisons, inline it all
into the BSS comparison function. This avoids
doing the IE searches twice and is also a lot
less code.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2013-01-30 00:40:20 +01:00
parent 4593c4cbe1
commit 3af6341c53
1 changed files with 39 additions and 81 deletions

View File

@ -288,26 +288,6 @@ const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
}
EXPORT_SYMBOL(cfg80211_find_vendor_ie);
static int cmp_ies(u8 num, const u8 *ies1, int len1, const u8 *ies2, int len2)
{
const u8 *ie1 = cfg80211_find_ie(num, ies1, len1);
const u8 *ie2 = cfg80211_find_ie(num, ies2, len2);
/* equal if both missing */
if (!ie1 && !ie2)
return 0;
/* sort missing IE before (left of) present IE */
if (!ie1)
return -1;
if (!ie2)
return 1;
/* sort by length first, then by contents */
if (ie1[1] != ie2[1])
return ie2[1] - ie1[1];
return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
}
static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
const u8 *ssid, size_t ssid_len)
{
@ -331,29 +311,6 @@ static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
return memcmp(ssidie + 2, ssid, ssid_len) == 0;
}
static bool is_mesh_bss(struct cfg80211_bss *a)
{
const struct cfg80211_bss_ies *ies;
const u8 *ie;
if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
return false;
ies = rcu_access_pointer(a->ies);
if (!ies)
return false;
ie = cfg80211_find_ie(WLAN_EID_MESH_ID, ies->data, ies->len);
if (!ie)
return false;
ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG, ies->data, ies->len);
if (!ie)
return false;
return true;
}
static bool is_mesh(struct cfg80211_bss *a,
const u8 *meshid, size_t meshidlen,
const u8 *meshcfg)
@ -391,39 +348,6 @@ static bool is_mesh(struct cfg80211_bss *a,
sizeof(struct ieee80211_meshconf_ie) - 2) == 0;
}
static int cmp_bss_core(struct cfg80211_bss *a, struct cfg80211_bss *b)
{
const struct cfg80211_bss_ies *a_ies, *b_ies;
int r;
if (a->channel != b->channel)
return b->channel->center_freq - a->channel->center_freq;
if (is_mesh_bss(a) && is_mesh_bss(b)) {
a_ies = rcu_access_pointer(a->ies);
if (!a_ies)
return -1;
b_ies = rcu_access_pointer(b->ies);
if (!b_ies)
return 1;
r = cmp_ies(WLAN_EID_MESH_ID,
a_ies->data, a_ies->len,
b_ies->data, b_ies->len);
if (r)
return r;
return cmp_ies(WLAN_EID_MESH_CONFIG,
a_ies->data, a_ies->len,
b_ies->data, b_ies->len);
}
/*
* we can't use compare_ether_addr here since we need a < > operator.
* The binary return value of compare_ether_addr isn't enough
*/
return memcmp(a->bssid, b->bssid, sizeof(a->bssid));
}
/**
* enum bss_compare_mode - BSS compare mode
* @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
@ -441,13 +365,12 @@ static int cmp_bss(struct cfg80211_bss *a,
enum bss_compare_mode mode)
{
const struct cfg80211_bss_ies *a_ies, *b_ies;
const u8 *ie1;
const u8 *ie2;
const u8 *ie1 = NULL;
const u8 *ie2 = NULL;
int i, r;
r = cmp_bss_core(a, b);
if (r)
return r;
if (a->channel != b->channel)
return b->channel->center_freq - a->channel->center_freq;
a_ies = rcu_access_pointer(a->ies);
if (!a_ies)
@ -456,6 +379,41 @@ static int cmp_bss(struct cfg80211_bss *a,
if (!b_ies)
return 1;
if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
a_ies->data, a_ies->len);
if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
b_ies->data, b_ies->len);
if (ie1 && ie2) {
int mesh_id_cmp;
if (ie1[1] == ie2[1])
mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
else
mesh_id_cmp = ie2[1] - ie1[1];
ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
a_ies->data, a_ies->len);
ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
b_ies->data, b_ies->len);
if (ie1 && ie2) {
if (mesh_id_cmp)
return mesh_id_cmp;
if (ie1[1] != ie2[1])
return ie2[1] - ie1[1];
return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
}
}
/*
* we can't use compare_ether_addr here since we need a < > operator.
* The binary return value of compare_ether_addr isn't enough
*/
r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
if (r)
return r;
ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);