WPS: Add support for setting timeout for PIN

[wpasupplicant] / src / wps / wps_registrar.c

diff --git a/src/wps/wps_registrar.c b/src/wps/wps_registrar.c
index 128bda3..0bbde67 100644 (file)
--- a/src/wps/wps_registrar.c
+++ b/src/wps/wps_registrar.c
@@ -32,7 +32,10 @@ struct wps_uuid_pin {
        int wildcard_uuid;
        u8 *pin;
        size_t pin_len;
-       int locked;
+#define PIN_LOCKED BIT(0)
+#define PIN_EXPIRES BIT(1)
+       int flags;
+       struct os_time expiration;
 };
 
 
@@ -413,10 +416,11 @@ void wps_registrar_deinit(struct wps_registrar *reg)
  * @uuid: UUID-E or %NULL for wildcard (any UUID)
  * @pin: PIN (Device Password)
  * @pin_len: Length of pin in octets
+ * @timeout: Time (in seconds) when the PIN will be invalidated; 0 = no timeout
  * Returns: 0 on success, -1 on failure
  */
 int wps_registrar_add_pin(struct wps_registrar *reg, const u8 *uuid,
-                         const u8 *pin, size_t pin_len)
+                         const u8 *pin, size_t pin_len, int timeout)
 {
        struct wps_uuid_pin *p;
 
@@ -435,10 +439,17 @@ int wps_registrar_add_pin(struct wps_registrar *reg, const u8 *uuid,
        os_memcpy(p->pin, pin, pin_len);
        p->pin_len = pin_len;
 
+       if (timeout) {
+               p->flags |= PIN_EXPIRES;
+               os_get_time(&p->expiration);
+               p->expiration.sec += timeout;
+       }
+
        p->next = reg->pins;
        reg->pins = p;
 
-       wpa_printf(MSG_DEBUG, "WPS: A new PIN configured");
+       wpa_printf(MSG_DEBUG, "WPS: A new PIN configured (timeout=%d)",
+                  timeout);
        wpa_hexdump(MSG_DEBUG, "WPS: UUID", uuid, WPS_UUID_LEN);
        wpa_hexdump_ascii_key(MSG_DEBUG, "WPS: PIN", pin, pin_len);
        reg->selected_registrar = 1;
@@ -449,6 +460,34 @@ int wps_registrar_add_pin(struct wps_registrar *reg, const u8 *uuid,
 }
 
 
+static void wps_registrar_expire_pins(struct wps_registrar *reg)
+{
+       struct wps_uuid_pin *pin, *prev, *del;
+       struct os_time now;
+
+       os_get_time(&now);
+       prev = NULL;
+       pin = reg->pins;
+       while (pin) {
+               if ((pin->flags & PIN_EXPIRES) &&
+                   os_time_before(&pin->expiration, &now)) {
+                       if (prev == NULL)
+                               reg->pins = pin->next;
+                       else
+                               prev->next = pin->next;
+                       del = pin;
+                       pin = pin->next;
+                       wpa_hexdump(MSG_DEBUG, "WPS: Expired PIN for UUID",
+                                   del->uuid, WPS_UUID_LEN);
+                       wps_free_pin(del);
+                       continue;
+               }
+               prev = pin;
+               pin = pin->next;
+       }
+}
+
+
 /**
  * wps_registrar_invalidate_pin - Invalidate a PIN for a specific UUID-E
  * @reg: Registrar data from wps_registrar_init()
@@ -485,6 +524,8 @@ static const u8 * wps_registrar_get_pin(struct wps_registrar *reg,
 {
        struct wps_uuid_pin *pin;
 
+       wps_registrar_expire_pins(reg);
+
        pin = reg->pins;
        while (pin) {
                if (!pin->wildcard_uuid &&
@@ -516,13 +557,13 @@ static const u8 * wps_registrar_get_pin(struct wps_registrar *reg,
         * Lock the PIN to avoid attacks based on concurrent re-use of the PIN
         * that could otherwise avoid PIN invalidations.
         */
-       if (pin->locked) {
+       if (pin->flags & PIN_LOCKED) {
                wpa_printf(MSG_DEBUG, "WPS: Selected PIN locked - do not "
                           "allow concurrent re-use");
                return NULL;
        }
        *pin_len = pin->pin_len;
-       pin->locked = 1;
+       pin->flags |= PIN_LOCKED;
        return pin->pin;
 }
 
@@ -549,7 +590,7 @@ int wps_registrar_unlock_pin(struct wps_registrar *reg, const u8 *uuid)
                                           "wildcard PIN");
                                return wps_registrar_invalidate_pin(reg, uuid);
                        }
-                       pin->locked = 0;
+                       pin->flags &= ~PIN_LOCKED;
                        return 0;
                }
                pin = pin->next;