[PATCH 07/15] AP: Rename SAE anti clogging variables and functions
Ilan Peer
ilan.peer at intel.com
Mon Mar 15 12:57:05 GMT 2021
PASN authentication mandates support for comeback flow, which
among others can be used for anti-clogging purposes.
As the SAE support for anti clogging can also be used for PASN,
start modifying the source code so the anti clogging support
can be used for both SAE and PASN.
As a start, rename some variables/functions etc. so that they
would not be SAE specific.
Signed-off-by: Ilan Peer <ilan.peer at intel.com>
---
hostapd/config_file.c | 5 ++--
hostapd/hostapd.conf | 3 +-
src/ap/ap_config.c | 2 +-
src/ap/ap_config.h | 2 +-
src/ap/hostapd.h | 8 ++---
src/ap/ieee802_11.c | 70 +++++++++++++++++++++++--------------------
6 files changed, 49 insertions(+), 41 deletions(-)
diff --git a/hostapd/config_file.c b/hostapd/config_file.c
index eabf61be07..fd9bc0e9fc 100644
--- a/hostapd/config_file.c
+++ b/hostapd/config_file.c
@@ -4276,8 +4276,9 @@ static int hostapd_config_fill(struct hostapd_config *conf,
} else if (os_strcmp(buf, "assocresp_elements") == 0) {
if (parse_wpabuf_hex(line, buf, &bss->assocresp_elements, pos))
return 1;
- } else if (os_strcmp(buf, "sae_anti_clogging_threshold") == 0) {
- bss->sae_anti_clogging_threshold = atoi(pos);
+ } else if (os_strcmp(buf, "sae_anti_clogging_threshold") == 0 ||
+ os_strcmp(buf, "anti_clogging_threshold") == 0) {
+ bss->anti_clogging_threshold = atoi(pos);
} else if (os_strcmp(buf, "sae_sync") == 0) {
bss->sae_sync = atoi(pos);
} else if (os_strcmp(buf, "sae_groups") == 0) {
diff --git a/hostapd/hostapd.conf b/hostapd/hostapd.conf
index 842639649f..e3ee8b2a0c 100644
--- a/hostapd/hostapd.conf
+++ b/hostapd/hostapd.conf
@@ -1886,7 +1886,8 @@ own_ip_addr=127.0.0.1
# SAE threshold for anti-clogging mechanism (dot11RSNASAEAntiCloggingThreshold)
# This parameter defines how many open SAE instances can be in progress at the
# same time before the anti-clogging mechanism is taken into use.
-#sae_anti_clogging_threshold=5
+#sae_anti_clogging_threshold=5 (deprecated)
+#anti_clogging_threshold=5
# Maximum number of SAE synchronization errors (dot11RSNASAESync)
# The offending SAE peer will be disconnected if more than this many
diff --git a/src/ap/ap_config.c b/src/ap/ap_config.c
index 611fa2e2c2..452386b7e5 100644
--- a/src/ap/ap_config.c
+++ b/src/ap/ap_config.c
@@ -121,7 +121,7 @@ void hostapd_config_defaults_bss(struct hostapd_bss_config *bss)
bss->radius_das_time_window = 300;
- bss->sae_anti_clogging_threshold = 5;
+ bss->anti_clogging_threshold = 5;
bss->sae_sync = 5;
bss->gas_frag_limit = 1400;
diff --git a/src/ap/ap_config.h b/src/ap/ap_config.h
index e2bd5e9358..25b0a6a5c8 100644
--- a/src/ap/ap_config.h
+++ b/src/ap/ap_config.h
@@ -655,7 +655,7 @@ struct hostapd_bss_config {
struct wpabuf *vendor_elements;
struct wpabuf *assocresp_elements;
- unsigned int sae_anti_clogging_threshold;
+ unsigned int anti_clogging_threshold;
unsigned int sae_sync;
int sae_require_mfp;
int sae_confirm_immediate;
diff --git a/src/ap/hostapd.h b/src/ap/hostapd.h
index 0736f451df..44f566a424 100644
--- a/src/ap/hostapd.h
+++ b/src/ap/hostapd.h
@@ -326,10 +326,10 @@ struct hostapd_data {
#ifdef CONFIG_SAE
/** Key used for generating SAE anti-clogging tokens */
- u8 sae_token_key[8];
- struct os_reltime last_sae_token_key_update;
- u16 sae_token_idx;
- u16 sae_pending_token_idx[256];
+ u8 comeback_key[8];
+ struct os_reltime last_comeback_key_update;
+ u16 comeback_idx;
+ u16 comeback_pending_idx[256];
int dot11RSNASAERetransPeriod; /* msec */
struct dl_list sae_commit_queue; /* struct hostapd_sae_commit_queue */
#endif /* CONFIG_SAE */
diff --git a/src/ap/ieee802_11.c b/src/ap/ieee802_11.c
index f88c8b3c21..689a51fe51 100644
--- a/src/ap/ieee802_11.c
+++ b/src/ap/ieee802_11.c
@@ -688,12 +688,12 @@ static int auth_sae_send_confirm(struct hostapd_data *hapd,
}
-static int use_sae_anti_clogging(struct hostapd_data *hapd)
+static int use_anti_clogging(struct hostapd_data *hapd)
{
struct sta_info *sta;
unsigned int open = 0;
- if (hapd->conf->sae_anti_clogging_threshold == 0)
+ if (hapd->conf->anti_clogging_threshold == 0)
return 1;
for (sta = hapd->sta_list; sta; sta = sta->next) {
@@ -703,7 +703,7 @@ static int use_sae_anti_clogging(struct hostapd_data *hapd)
sta->sae->state != SAE_CONFIRMED)
continue;
open++;
- if (open >= hapd->conf->sae_anti_clogging_threshold)
+ if (open >= hapd->conf->anti_clogging_threshold)
return 1;
}
@@ -711,18 +711,19 @@ static int use_sae_anti_clogging(struct hostapd_data *hapd)
* there are enough pending commit messages in the processing queue to
* potentially result in too many open sessions. */
if (open + dl_list_len(&hapd->sae_commit_queue) >=
- hapd->conf->sae_anti_clogging_threshold)
+ hapd->conf->anti_clogging_threshold)
return 1;
return 0;
}
-static int sae_token_hash(struct hostapd_data *hapd, const u8 *addr, u8 *idx)
+static int comeback_token_hash(struct hostapd_data *hapd, const u8 *addr,
+ u8 *idx)
{
u8 hash[SHA256_MAC_LEN];
- if (hmac_sha256(hapd->sae_token_key, sizeof(hapd->sae_token_key),
+ if (hmac_sha256(hapd->comeback_key, sizeof(hapd->comeback_key),
addr, ETH_ALEN, hash) < 0)
return -1;
*idx = hash[0];
@@ -730,8 +731,8 @@ static int sae_token_hash(struct hostapd_data *hapd, const u8 *addr, u8 *idx)
}
-static int check_sae_token(struct hostapd_data *hapd, const u8 *addr,
- const u8 *token, size_t token_len)
+static int check_comeback_token(struct hostapd_data *hapd, const u8 *addr,
+ const u8 *token, size_t token_len)
{
u8 mac[SHA256_MAC_LEN];
const u8 *addrs[2];
@@ -739,11 +740,13 @@ static int check_sae_token(struct hostapd_data *hapd, const u8 *addr,
u16 token_idx;
u8 idx;
- if (token_len != SHA256_MAC_LEN || sae_token_hash(hapd, addr, &idx) < 0)
+ if (token_len != SHA256_MAC_LEN ||
+ comeback_token_hash(hapd, addr, &idx) < 0)
return -1;
- token_idx = hapd->sae_pending_token_idx[idx];
+ token_idx = hapd->comeback_pending_idx[idx];
if (token_idx == 0 || token_idx != WPA_GET_BE16(token)) {
- wpa_printf(MSG_DEBUG, "SAE: Invalid anti-clogging token from "
+ wpa_printf(MSG_DEBUG,
+ "Comeback: Invalid anti-clogging token from "
MACSTR " - token_idx 0x%04x, expected 0x%04x",
MAC2STR(addr), WPA_GET_BE16(token), token_idx);
return -1;
@@ -753,12 +756,12 @@ static int check_sae_token(struct hostapd_data *hapd, const u8 *addr,
len[0] = ETH_ALEN;
addrs[1] = token;
len[1] = 2;
- if (hmac_sha256_vector(hapd->sae_token_key, sizeof(hapd->sae_token_key),
+ if (hmac_sha256_vector(hapd->comeback_key, sizeof(hapd->comeback_key),
2, addrs, len, mac) < 0 ||
os_memcmp_const(token + 2, &mac[2], SHA256_MAC_LEN - 2) != 0)
return -1;
- hapd->sae_pending_token_idx[idx] = 0; /* invalidate used token */
+ hapd->comeback_pending_idx[idx] = 0; /* invalidate used token */
return 0;
}
@@ -777,18 +780,19 @@ static struct wpabuf * auth_build_token_req(struct hostapd_data *hapd,
u16 token_idx;
os_get_reltime(&now);
- if (!os_reltime_initialized(&hapd->last_sae_token_key_update) ||
- os_reltime_expired(&now, &hapd->last_sae_token_key_update, 60) ||
- hapd->sae_token_idx == 0xffff) {
- if (random_get_bytes(hapd->sae_token_key,
- sizeof(hapd->sae_token_key)) < 0)
+ if (!os_reltime_initialized(&hapd->last_comeback_key_update) ||
+ os_reltime_expired(&now, &hapd->last_comeback_key_update, 60) ||
+ hapd->comeback_idx == 0xffff) {
+ if (random_get_bytes(hapd->comeback_key,
+ sizeof(hapd->comeback_key)) < 0)
return NULL;
- wpa_hexdump(MSG_DEBUG, "SAE: Updated token key",
- hapd->sae_token_key, sizeof(hapd->sae_token_key));
- hapd->last_sae_token_key_update = now;
- hapd->sae_token_idx = 0;
- os_memset(hapd->sae_pending_token_idx, 0,
- sizeof(hapd->sae_pending_token_idx));
+ wpa_hexdump(MSG_DEBUG,
+ "Comeback: Updated token key",
+ hapd->comeback_key, sizeof(hapd->comeback_key));
+ hapd->last_comeback_key_update = now;
+ hapd->comeback_idx = 0;
+ os_memset(hapd->comeback_pending_idx, 0,
+ sizeof(hapd->comeback_pending_idx));
}
buf = wpabuf_alloc(sizeof(le16) + 3 + SHA256_MAC_LEN);
@@ -804,15 +808,16 @@ static struct wpabuf * auth_build_token_req(struct hostapd_data *hapd,
wpabuf_put_u8(buf, WLAN_EID_EXT_ANTI_CLOGGING_TOKEN);
}
- if (sae_token_hash(hapd, addr, &p_idx) < 0) {
+ if (comeback_token_hash(hapd, addr, &p_idx) < 0) {
wpabuf_free(buf);
return NULL;
}
- token_idx = hapd->sae_pending_token_idx[p_idx];
+
+ token_idx = hapd->comeback_pending_idx[p_idx];
if (!token_idx) {
- hapd->sae_token_idx++;
- token_idx = hapd->sae_token_idx;
- hapd->sae_pending_token_idx[p_idx] = token_idx;
+ hapd->comeback_idx++;
+ token_idx = hapd->comeback_idx;
+ hapd->comeback_pending_idx[p_idx] = token_idx;
}
WPA_PUT_BE16(idx, token_idx);
token = wpabuf_put(buf, SHA256_MAC_LEN);
@@ -820,7 +825,7 @@ static struct wpabuf * auth_build_token_req(struct hostapd_data *hapd,
len[0] = ETH_ALEN;
addrs[1] = idx;
len[1] = sizeof(idx);
- if (hmac_sha256_vector(hapd->sae_token_key, sizeof(hapd->sae_token_key),
+ if (hmac_sha256_vector(hapd->comeback_key, sizeof(hapd->comeback_key),
2, addrs, len, token) < 0) {
wpabuf_free(buf);
return NULL;
@@ -1452,7 +1457,8 @@ static void handle_auth_sae(struct hostapd_data *hapd, struct sta_info *sta,
goto remove_sta;
}
- if (token && check_sae_token(hapd, sta->addr, token, token_len)
+ if (token &&
+ check_comeback_token(hapd, sta->addr, token, token_len)
< 0) {
wpa_printf(MSG_DEBUG, "SAE: Drop commit message with "
"incorrect token from " MACSTR,
@@ -1469,7 +1475,7 @@ static void handle_auth_sae(struct hostapd_data *hapd, struct sta_info *sta,
goto reply;
}
- if (!token && use_sae_anti_clogging(hapd) && !allow_reuse) {
+ if (!token && use_anti_clogging(hapd) && !allow_reuse) {
int h2e = 0;
wpa_printf(MSG_DEBUG,
--
2.17.1
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