From d8912fd80eb99bf504486e07a6fe3b2a7c154b79 Mon Sep 17 00:00:00 2001 From: Michael Braun Date: Wed, 24 Feb 2016 12:53:37 +0100 Subject: [PATCH] Cache hashed passphrase in RADIUS-based PSK delivery Instead of copying the full struct hostapd_sta_wpa_psk_short, share the existing entry and use reference counting to check when it needs to be freed. This allows caching of PSKs derived from passphrases to avoid having to perform the heavy hashing operation multiple times. Signed-off-by: Michael Braun --- src/ap/ap_config.h | 1 + src/ap/ieee802_11_auth.c | 28 ++++++++++++---------------- 2 files changed, 13 insertions(+), 16 deletions(-) diff --git a/src/ap/ap_config.h b/src/ap/ap_config.h index 90405b4e3..492df6cc8 100644 --- a/src/ap/ap_config.h +++ b/src/ap/ap_config.h @@ -134,6 +134,7 @@ struct hostapd_sta_wpa_psk_short { unsigned int is_passphrase:1; u8 psk[PMK_LEN]; char passphrase[MAX_PASSPHRASE_LEN + 1]; + int ref; /* (number of references held) - 1 */ }; struct hostapd_wpa_psk { diff --git a/src/ap/ieee802_11_auth.c b/src/ap/ieee802_11_auth.c index 6afdc5db2..1ed8e7f47 100644 --- a/src/ap/ieee802_11_auth.c +++ b/src/ap/ieee802_11_auth.c @@ -76,23 +76,13 @@ static void hostapd_acl_cache_free(struct hostapd_cached_radius_acl *acl_cache) static void copy_psk_list(struct hostapd_sta_wpa_psk_short **psk, struct hostapd_sta_wpa_psk_short *src) { - struct hostapd_sta_wpa_psk_short **copy_to; - struct hostapd_sta_wpa_psk_short *copy_from; + if (!psk) + return; - /* Copy PSK linked list */ - copy_to = psk; - copy_from = src; - while (copy_from && copy_to) { - *copy_to = os_zalloc(sizeof(struct hostapd_sta_wpa_psk_short)); - if (*copy_to == NULL) - break; - os_memcpy(*copy_to, copy_from, - sizeof(struct hostapd_sta_wpa_psk_short)); - copy_from = copy_from->next; - copy_to = &((*copy_to)->next); - } - if (copy_to) - *copy_to = NULL; + if (src) + src->ref++; + + *psk = src; } @@ -667,6 +657,12 @@ void hostapd_acl_deinit(struct hostapd_data *hapd) void hostapd_free_psk_list(struct hostapd_sta_wpa_psk_short *psk) { + if (psk && psk->ref) { + /* This will be freed when the last reference is dropped. */ + psk->ref--; + return; + } + while (psk) { struct hostapd_sta_wpa_psk_short *prev = psk; psk = psk->next;