main/hostapd: fix CVE-2020-12695

See #11626

4 files changed, 275 insertions, 8 deletions

diff --git a/main/hostapd/0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch b/main/hostapd/0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch
new file mode 100644
index 00000000000..0aa8a5ea1de
--- /dev/null
+++ b/main/hostapd/0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch
@@ -0,0 +1,150 @@
+From 5b78c8f961f25f4dc22d6f2b77ddd06d712cec63 Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Wed, 3 Jun 2020 23:17:35 +0300
+Subject: [PATCH 1/3] WPS UPnP: Do not allow event subscriptions with URLs to
+ other networks
+
+The UPnP Device Architecture 2.0 specification errata ("UDA errata
+16-04-2020.docx") addresses a problem with notifications being allowed
+to go out to other domains by disallowing such cases. Do such filtering
+for the notification callback URLs to avoid undesired connections to
+external networks based on subscriptions that any device in the local
+network could request when WPS support for external registrars is
+enabled (the upnp_iface parameter in hostapd configuration).
+
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+---
+ src/wps/wps_er.c     |  2 +-
+ src/wps/wps_upnp.c   | 38 ++++++++++++++++++++++++++++++++++++--
+ src/wps/wps_upnp_i.h |  3 ++-
+ 3 files changed, 39 insertions(+), 4 deletions(-)
+
+diff --git a/src/wps/wps_er.c b/src/wps/wps_er.c
+index 6bded14327f8..31d2e50e4cff 100644
+--- a/src/wps/wps_er.c
++++ b/src/wps/wps_er.c
+@@ -1298,7 +1298,7 @@ wps_er_init(struct wps_context *wps, const char *ifname, const char *filter)
+ 			   "with %s", filter);
+ 	}
+ 	if (get_netif_info(er->ifname, &er->ip_addr, &er->ip_addr_text,
+-			   er->mac_addr)) {
++			   NULL, er->mac_addr)) {
+ 		wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
+ 			   "for %s. Does it have IP address?", er->ifname);
+ 		wps_er_deinit(er, NULL, NULL);
+diff --git a/src/wps/wps_upnp.c b/src/wps/wps_upnp.c
+index 6e10e4bc0c3f..7d4b7439940e 100644
+--- a/src/wps/wps_upnp.c
++++ b/src/wps/wps_upnp.c
+@@ -303,6 +303,14 @@ static void subscr_addr_free_all(struct subscription *s)
+ }
+ 
+ 
++static int local_network_addr(struct upnp_wps_device_sm *sm,
++			      struct sockaddr_in *addr)
++{
++	return (addr->sin_addr.s_addr & sm->netmask.s_addr) ==
++		(sm->ip_addr & sm->netmask.s_addr);
++}
++
++
+ /* subscr_addr_add_url -- add address(es) for one url to subscription */
+ static void subscr_addr_add_url(struct subscription *s, const char *url,
+ 				size_t url_len)
+@@ -381,6 +389,7 @@ static void subscr_addr_add_url(struct subscription *s, const char *url,
+ 
+ 	for (rp = result; rp; rp = rp->ai_next) {
+ 		struct subscr_addr *a;
++		struct sockaddr_in *addr = (struct sockaddr_in *) rp->ai_addr;
+ 
+ 		/* Limit no. of address to avoid denial of service attack */
+ 		if (dl_list_len(&s->addr_list) >= MAX_ADDR_PER_SUBSCRIPTION) {
+@@ -389,6 +398,13 @@ static void subscr_addr_add_url(struct subscription *s, const char *url,
+ 			break;
+ 		}
+ 
++		if (!local_network_addr(s->sm, addr)) {
++			wpa_printf(MSG_INFO,
++				   "WPS UPnP: Ignore a delivery URL that points to another network %s",
++				   inet_ntoa(addr->sin_addr));
++			continue;
++		}
++
+ 		a = os_zalloc(sizeof(*a) + alloc_len);
+ 		if (a == NULL)
+ 			break;
+@@ -890,11 +906,12 @@ static int eth_get(const char *device, u8 ea[ETH_ALEN])
+  * @net_if: Selected network interface name
+  * @ip_addr: Buffer for returning IP address in network byte order
+  * @ip_addr_text: Buffer for returning a pointer to allocated IP address text
++ * @netmask: Buffer for returning netmask or %NULL if not needed
+  * @mac: Buffer for returning MAC address
+  * Returns: 0 on success, -1 on failure
+  */
+ int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
+-		   u8 mac[ETH_ALEN])
++		   struct in_addr *netmask, u8 mac[ETH_ALEN])
+ {
+ 	struct ifreq req;
+ 	int sock = -1;
+@@ -920,6 +937,19 @@ int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
+ 	in_addr.s_addr = *ip_addr;
+ 	os_snprintf(*ip_addr_text, 16, "%s", inet_ntoa(in_addr));
+ 
++	if (netmask) {
++		os_memset(&req, 0, sizeof(req));
++		os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
++		if (ioctl(sock, SIOCGIFNETMASK, &req) < 0) {
++			wpa_printf(MSG_ERROR,
++				   "WPS UPnP: SIOCGIFNETMASK failed: %d (%s)",
++				   errno, strerror(errno));
++			goto fail;
++		}
++		addr = (struct sockaddr_in *) &req.ifr_netmask;
++		netmask->s_addr = addr->sin_addr.s_addr;
++	}
++
+ #ifdef __linux__
+ 	os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
+ 	if (ioctl(sock, SIOCGIFHWADDR, &req) < 0) {
+@@ -1026,11 +1056,15 @@ static int upnp_wps_device_start(struct upnp_wps_device_sm *sm, char *net_if)
+ 
+ 	/* Determine which IP and mac address we're using */
+ 	if (get_netif_info(net_if, &sm->ip_addr, &sm->ip_addr_text,
+-			   sm->mac_addr)) {
++			   &sm->netmask, sm->mac_addr)) {
+ 		wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
+ 			   "for %s. Does it have IP address?", net_if);
+ 		goto fail;
+ 	}
++	wpa_printf(MSG_DEBUG, "WPS UPnP: Local IP address %s netmask %s hwaddr "
++		   MACSTR,
++		   sm->ip_addr_text, inet_ntoa(sm->netmask),
++		   MAC2STR(sm->mac_addr));
+ 
+ 	/* Listen for incoming TCP connections so that others
+ 	 * can fetch our "xml files" from us.
+diff --git a/src/wps/wps_upnp_i.h b/src/wps/wps_upnp_i.h
+index e87a93232df1..6ead7b4e9a30 100644
+--- a/src/wps/wps_upnp_i.h
++++ b/src/wps/wps_upnp_i.h
+@@ -128,6 +128,7 @@ struct upnp_wps_device_sm {
+ 	u8 mac_addr[ETH_ALEN]; /* mac addr of network i.f. we use */
+ 	char *ip_addr_text; /* IP address of network i.f. we use */
+ 	unsigned ip_addr; /* IP address of network i.f. we use (host order) */
++	struct in_addr netmask;
+ 	int multicast_sd; /* send multicast messages over this socket */
+ 	int ssdp_sd; /* receive discovery UPD packets on socket */
+ 	int ssdp_sd_registered; /* nonzero if we must unregister */
+@@ -158,7 +159,7 @@ struct subscription * subscription_find(struct upnp_wps_device_sm *sm,
+ 					const u8 uuid[UUID_LEN]);
+ void subscr_addr_delete(struct subscr_addr *a);
+ int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
+-		   u8 mac[ETH_ALEN]);
++		   struct in_addr *netmask, u8 mac[ETH_ALEN]);
+ 
+ /* wps_upnp_ssdp.c */
+ void msearchreply_state_machine_stop(struct advertisement_state_machine *a);
+-- 
+2.20.1
+
diff --git a/main/hostapd/0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch b/main/hostapd/0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch
new file mode 100644
index 00000000000..c7a449e0b5c
--- /dev/null
+++ b/main/hostapd/0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch
@@ -0,0 +1,59 @@
+From f7d268864a2660b7239b9a8ff5ad37faeeb751ba Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Wed, 3 Jun 2020 22:41:02 +0300
+Subject: [PATCH 2/3] WPS UPnP: Fix event message generation using a long URL
+ path
+
+More than about 700 character URL ended up overflowing the wpabuf used
+for building the event notification and this resulted in the wpabuf
+buffer overflow checks terminating the hostapd process. Fix this by
+allocating the buffer to be large enough to contain the full URL path.
+However, since that around 700 character limit has been the practical
+limit for more than ten years, start explicitly enforcing that as the
+limit or the callback URLs since any longer ones had not worked before
+and there is no need to enable them now either.
+
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+---
+ src/wps/wps_upnp.c       | 9 +++++++--
+ src/wps/wps_upnp_event.c | 3 ++-
+ 2 files changed, 9 insertions(+), 3 deletions(-)
+
+diff --git a/src/wps/wps_upnp.c b/src/wps/wps_upnp.c
+index 7d4b7439940e..ab685d52ecab 100644
+--- a/src/wps/wps_upnp.c
++++ b/src/wps/wps_upnp.c
+@@ -328,9 +328,14 @@ static void subscr_addr_add_url(struct subscription *s, const char *url,
+ 	int rerr;
+ 	size_t host_len, path_len;
+ 
+-	/* url MUST begin with http: */
+-	if (url_len < 7 || os_strncasecmp(url, "http://", 7))
++	/* URL MUST begin with HTTP scheme. In addition, limit the length of
++	 * the URL to 700 characters which is around the limit that was
++	 * implicitly enforced for more than 10 years due to a bug in
++	 * generating the event messages. */
++	if (url_len < 7 || os_strncasecmp(url, "http://", 7) || url_len > 700) {
++		wpa_printf(MSG_DEBUG, "WPS UPnP: Reject an unacceptable URL");
+ 		goto fail;
++	}
+ 	url += 7;
+ 	url_len -= 7;
+ 
+diff --git a/src/wps/wps_upnp_event.c b/src/wps/wps_upnp_event.c
+index d7e6edcc6503..08a23612f338 100644
+--- a/src/wps/wps_upnp_event.c
++++ b/src/wps/wps_upnp_event.c
+@@ -147,7 +147,8 @@ static struct wpabuf * event_build_message(struct wps_event_ *e)
+ 	struct wpabuf *buf;
+ 	char *b;
+ 
+-	buf = wpabuf_alloc(1000 + wpabuf_len(e->data));
++	buf = wpabuf_alloc(1000 + os_strlen(e->addr->path) +
++			   wpabuf_len(e->data));
+ 	if (buf == NULL)
+ 		return NULL;
+ 	wpabuf_printf(buf, "NOTIFY %s HTTP/1.1\r\n", e->addr->path);
+-- 
+2.20.1
+
diff --git a/main/hostapd/0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch b/main/hostapd/0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch
new file mode 100644
index 00000000000..9d0376043d0
--- /dev/null
+++ b/main/hostapd/0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch
@@ -0,0 +1,47 @@
+From 85aac526af8612c21b3117dadc8ef5944985b476 Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Thu, 4 Jun 2020 21:24:04 +0300
+Subject: [PATCH 3/3] WPS UPnP: Handle HTTP initiation failures for events more
+ properly
+
+While it is appropriate to try to retransmit the event to another
+callback URL on a failure to initiate the HTTP client connection, there
+is no point in trying the exact same operation multiple times in a row.
+Replve the event_retry() calls with event_addr_failure() for these cases
+to avoid busy loops trying to repeat the same failing operation.
+
+These potential busy loops would go through eloop callbacks, so the
+process is not completely stuck on handling them, but unnecessary CPU
+would be used to process the continues retries that will keep failing
+for the same reason.
+
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+---
+ src/wps/wps_upnp_event.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/wps/wps_upnp_event.c b/src/wps/wps_upnp_event.c
+index 08a23612f338..c0d9e41d9a38 100644
+--- a/src/wps/wps_upnp_event.c
++++ b/src/wps/wps_upnp_event.c
+@@ -294,7 +294,7 @@ static int event_send_start(struct subscription *s)
+ 
+ 	buf = event_build_message(e);
+ 	if (buf == NULL) {
+-		event_retry(e, 0);
++		event_addr_failure(e);
+ 		return -1;
+ 	}
+ 
+@@ -302,7 +302,7 @@ static int event_send_start(struct subscription *s)
+ 					 event_http_cb, e);
+ 	if (e->http_event == NULL) {
+ 		wpabuf_free(buf);
+-		event_retry(e, 0);
++		event_addr_failure(e);
+ 		return -1;
+ 	}
+ 
+-- 
+2.20.1
+
diff --git a/main/hostapd/APKBUILD b/main/hostapd/APKBUILD
index 098241c17ee..dc6571eaef3 100644
--- a/main/hostapd/APKBUILD
+++ b/main/hostapd/APKBUILD
@@ -1,23 +1,27 @@
 # Maintainer: Natanael Copa <ncopa@alpinelinux.org>
 pkgname=hostapd
 pkgver=2.9
-pkgrel=1
+pkgrel=2
 pkgdesc="daemon for wireless software access points"
 url="https://w1.fi/hostapd/"
 arch="all"
 license="custom"
 makedepends="openssl-dev libnl3-dev linux-headers"
 subpackages="$pkgname-doc $pkgname-openrc"
-patches="CVE-2019-16275.patch"
 source="https://w1.fi/releases/$pkgname-$pkgver.tar.gz
-	$patches
 	$pkgname.initd
 	$pkgname.confd
+	CVE-2019-16275.patch
+	0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch
+	0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch
+	0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch
 	"
 options="!check" #no testsuite
 builddir="$srcdir"/$pkgname-$pkgver/hostapd
 
 # secfixes:
+#   2.9-r2:
+#     - CVE-2020-12695
 #   2.9-r1:
 #     - CVE-2019-16275
 #   2.8-r0:
@@ -39,10 +43,14 @@ builddir="$srcdir"/$pkgname-$pkgver/hostapd
 prepare() {
 	local conf="$builddir/.config"
 
+	# This is required because our builddir is the hostapd/ directory
+	# inside the extracted archive, while patches mostly apply against
+	# the src/ directory that is in the same directory as the hostapd/
+	# one is
 	cd "$builddir"/..
-	for i in $patches; do
-		msg $i
-		patch -p1 -i "$srcdir"/$i
+	for i in "$srcdir"/*.patch; do
+		msg "Applying $i..."
+		patch -p1 -i $i
 	done
 
 	cd "$builddir"
@@ -95,6 +103,9 @@ package() {
 			"$pkgdir"/usr/share/man/man1/hostapd_cli
 }
 sha512sums="66c729380152db18b64520bda55dfa00af3b0264f97b5de100b81a46e2593571626c4bdcf900f0988ea2131e30bc8788f75d8489dd1f57e37fd56e8098e48a9c  hostapd-2.9.tar.gz
-63710cfb0992f2c346a9807d8c97cbeaed032fa376a0e93a2e56f7742ce515e9c4dfadbdb1af03ba272281f639aab832f0178f67634c222a5d99e1d462aa9e38  CVE-2019-16275.patch
 b54b7c6aa17e5cb86a9b354a516eb2dbefb544df18471339c61d82776de447011a2ac290bea1e6c8beae4b6cebefafb8174683ea42fb773e9e8fe6c679f33ba3  hostapd.initd
-0882263bbd7c0b05bf51f51d66e11a23a0b8ca7da2a3b8a30166d2c5f044c0c134e6bccb1d02c9e81819ca8fb0c0fb55c7121a08fe7233ccaa73ff8ab9a238fe  hostapd.confd"
+0882263bbd7c0b05bf51f51d66e11a23a0b8ca7da2a3b8a30166d2c5f044c0c134e6bccb1d02c9e81819ca8fb0c0fb55c7121a08fe7233ccaa73ff8ab9a238fe  hostapd.confd
+63710cfb0992f2c346a9807d8c97cbeaed032fa376a0e93a2e56f7742ce515e9c4dfadbdb1af03ba272281f639aab832f0178f67634c222a5d99e1d462aa9e38  CVE-2019-16275.patch
+b76bbca282a74ef16c0303e5dbd2ccd33a62461595964d52c1481b0bfa4f41deacde56830b85409b288803b87ceb6f33cf0ccc69c5b17ec632c2d4784b872f3c  0001-WPS-UPnP-Do-not-allow-event-subscriptions-with-URLs-.patch
+00cc739e78c42353a555c0de2f29defecff372927040e14407a231d1ead7ff32a37c9fd46bea7cdf1c24e3ac891bc3d483800d44fc6d2c8a12d2ae886523b12c  0002-WPS-UPnP-Fix-event-message-generation-using-a-long-U.patch
+69243af20cdcfa837c51917a3723779f4825e11436fb83311355b4ffe8f7a4b7a5747a976f7bf923038c410c9e9055b13b866d9a396913ad08bdec3a70e9f6e0  0003-WPS-UPnP-Handle-HTTP-initiation-failures-for-events-.patch"