1 /*
2 * wpa_supplicant - Temporary BSSID blacklist
3 * Copyright (c) 2003-2007, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "wpa_supplicant_i.h"
13 #include "blacklist.h"
14
15 /**
16 * wpa_blacklist_get - Get the blacklist entry for a BSSID
17 * @wpa_s: Pointer to wpa_supplicant data
18 * @bssid: BSSID
19 * Returns: Matching blacklist entry for the BSSID or %NULL if not found
20 */
wpa_blacklist_get(struct wpa_supplicant * wpa_s,const u8 * bssid)21 struct wpa_blacklist * wpa_blacklist_get(struct wpa_supplicant *wpa_s,
22 const u8 *bssid)
23 {
24 struct wpa_blacklist *e;
25
26 if (wpa_s == NULL || bssid == NULL)
27 return NULL;
28
29 e = wpa_s->blacklist;
30 while (e) {
31 if (os_memcmp(e->bssid, bssid, ETH_ALEN) == 0)
32 return e;
33 e = e->next;
34 }
35
36 return NULL;
37 }
38
39
40 /**
41 * wpa_blacklist_add - Add an BSSID to the blacklist
42 * @wpa_s: Pointer to wpa_supplicant data
43 * @bssid: BSSID to be added to the blacklist
44 * Returns: Current blacklist count on success, -1 on failure
45 *
46 * This function adds the specified BSSID to the blacklist or increases the
47 * blacklist count if the BSSID was already listed. It should be called when
48 * an association attempt fails either due to the selected BSS rejecting
49 * association or due to timeout.
50 *
51 * This blacklist is used to force %wpa_supplicant to go through all available
52 * BSSes before retrying to associate with an BSS that rejected or timed out
53 * association. It does not prevent the listed BSS from being used; it only
54 * changes the order in which they are tried.
55 */
wpa_blacklist_add(struct wpa_supplicant * wpa_s,const u8 * bssid)56 int wpa_blacklist_add(struct wpa_supplicant *wpa_s, const u8 *bssid)
57 {
58 struct wpa_blacklist *e;
59
60 if (wpa_s == NULL || bssid == NULL)
61 return -1;
62
63 e = wpa_blacklist_get(wpa_s, bssid);
64 if (e) {
65 e->count++;
66 wpa_printf(MSG_DEBUG, "BSSID " MACSTR " blacklist count "
67 "incremented to %d",
68 MAC2STR(bssid), e->count);
69 return e->count;
70 }
71
72 e = os_zalloc(sizeof(*e));
73 if (e == NULL)
74 return -1;
75 os_memcpy(e->bssid, bssid, ETH_ALEN);
76 e->count = 1;
77 e->next = wpa_s->blacklist;
78 wpa_s->blacklist = e;
79 wpa_printf(MSG_DEBUG, "Added BSSID " MACSTR " into blacklist",
80 MAC2STR(bssid));
81
82 return e->count;
83 }
84
85
86 /**
87 * wpa_blacklist_del - Remove an BSSID from the blacklist
88 * @wpa_s: Pointer to wpa_supplicant data
89 * @bssid: BSSID to be removed from the blacklist
90 * Returns: 0 on success, -1 on failure
91 */
wpa_blacklist_del(struct wpa_supplicant * wpa_s,const u8 * bssid)92 int wpa_blacklist_del(struct wpa_supplicant *wpa_s, const u8 *bssid)
93 {
94 struct wpa_blacklist *e, *prev = NULL;
95
96 if (wpa_s == NULL || bssid == NULL)
97 return -1;
98
99 e = wpa_s->blacklist;
100 while (e) {
101 if (os_memcmp(e->bssid, bssid, ETH_ALEN) == 0) {
102 if (prev == NULL) {
103 wpa_s->blacklist = e->next;
104 } else {
105 prev->next = e->next;
106 }
107 wpa_printf(MSG_DEBUG, "Removed BSSID " MACSTR " from "
108 "blacklist", MAC2STR(bssid));
109 os_free(e);
110 return 0;
111 }
112 prev = e;
113 e = e->next;
114 }
115 return -1;
116 }
117
118
119 /**
120 * wpa_blacklist_clear - Clear the blacklist of all entries
121 * @wpa_s: Pointer to wpa_supplicant data
122 */
wpa_blacklist_clear(struct wpa_supplicant * wpa_s)123 void wpa_blacklist_clear(struct wpa_supplicant *wpa_s)
124 {
125 struct wpa_blacklist *e, *prev;
126 int max_count = 0;
127
128 e = wpa_s->blacklist;
129 wpa_s->blacklist = NULL;
130 while (e) {
131 if (e->count > max_count)
132 max_count = e->count;
133 prev = e;
134 e = e->next;
135 wpa_printf(MSG_DEBUG, "Removed BSSID " MACSTR " from "
136 "blacklist (clear)", MAC2STR(prev->bssid));
137 os_free(prev);
138 }
139
140 wpa_s->extra_blacklist_count += max_count;
141 }
142