1 /* 2 * wpa_supplicant - Temporary BSSID blacklist 3 * Copyright (c) 2003-2007, Jouni Malinen <j (at) w1.fi> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * Alternatively, this software may be distributed under the terms of BSD 10 * license. 11 * 12 * See README and COPYING for more details. 13 */ 14 15 #include "includes.h" 16 17 #include "common.h" 18 #include "wpa_supplicant_i.h" 19 #include "blacklist.h" 20 21 /** 22 * wpa_blacklist_get - Get the blacklist entry for a BSSID 23 * @wpa_s: Pointer to wpa_supplicant data 24 * @bssid: BSSID 25 * Returns: Matching blacklist entry for the BSSID or %NULL if not found 26 */ 27 struct wpa_blacklist * wpa_blacklist_get(struct wpa_supplicant *wpa_s, 28 const u8 *bssid) 29 { 30 struct wpa_blacklist *e; 31 32 e = wpa_s->blacklist; 33 while (e) { 34 if (os_memcmp(e->bssid, bssid, ETH_ALEN) == 0) 35 return e; 36 e = e->next; 37 } 38 39 return NULL; 40 } 41 42 43 /** 44 * wpa_blacklist_add - Add an BSSID to the blacklist 45 * @wpa_s: Pointer to wpa_supplicant data 46 * @bssid: BSSID to be added to the blacklist 47 * Returns: 0 on success, -1 on failure 48 * 49 * This function adds the specified BSSID to the blacklist or increases the 50 * blacklist count if the BSSID was already listed. It should be called when 51 * an association attempt fails either due to the selected BSS rejecting 52 * association or due to timeout. 53 * 54 * This blacklist is used to force %wpa_supplicant to go through all available 55 * BSSes before retrying to associate with an BSS that rejected or timed out 56 * association. It does not prevent the listed BSS from being used; it only 57 * changes the order in which they are tried. 58 */ 59 int wpa_blacklist_add(struct wpa_supplicant *wpa_s, const u8 *bssid) 60 { 61 struct wpa_blacklist *e; 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 0; 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 0; 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 */ 92 int wpa_blacklist_del(struct wpa_supplicant *wpa_s, const u8 *bssid) 93 { 94 struct wpa_blacklist *e, *prev = NULL; 95 96 e = wpa_s->blacklist; 97 while (e) { 98 if (os_memcmp(e->bssid, bssid, ETH_ALEN) == 0) { 99 if (prev == NULL) { 100 wpa_s->blacklist = e->next; 101 } else { 102 prev->next = e->next; 103 } 104 wpa_printf(MSG_DEBUG, "Removed BSSID " MACSTR " from " 105 "blacklist", MAC2STR(bssid)); 106 os_free(e); 107 return 0; 108 } 109 prev = e; 110 e = e->next; 111 } 112 return -1; 113 } 114 115 116 /** 117 * wpa_blacklist_clear - Clear the blacklist of all entries 118 * @wpa_s: Pointer to wpa_supplicant data 119 */ 120 void wpa_blacklist_clear(struct wpa_supplicant *wpa_s) 121 { 122 struct wpa_blacklist *e, *prev; 123 124 e = wpa_s->blacklist; 125 wpa_s->blacklist = NULL; 126 while (e) { 127 prev = e; 128 e = e->next; 129 wpa_printf(MSG_DEBUG, "Removed BSSID " MACSTR " from " 130 "blacklist (clear)", MAC2STR(prev->bssid)); 131 os_free(prev); 132 } 133 } 134