KRACK attack: Patch wpa_supplicant & hostapd

[people/pmueller/ipfire-2.x.git] / src / patches / wpa_supplicant / rebased-v2.6-0005-Fix-PTK-rekeying-to-generate-a-new-ANonce.patch

diff --git a/src/patches/wpa_supplicant/rebased-v2.6-0005-Fix-PTK-rekeying-to-generate-a-new-ANonce.patch b/src/patches/wpa_supplicant/rebased-v2.6-0005-Fix-PTK-rekeying-to-generate-a-new-ANonce.patch
new file mode 100644 (file)
index 0000000..c19c4c7
--- /dev/null
+++ b/src/patches/wpa_supplicant/rebased-v2.6-0005-Fix-PTK-rekeying-to-generate-a-new-ANonce.patch
@@ -0,0 +1,64 @@
+From 12fac09b437a1dc8a0f253e265934a8aaf4d2f8b Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <j@w1.fi>
+Date: Sun, 1 Oct 2017 12:32:57 +0300
+Subject: [PATCH 5/8] Fix PTK rekeying to generate a new ANonce
+
+The Authenticator state machine path for PTK rekeying ended up bypassing
+the AUTHENTICATION2 state where a new ANonce is generated when going
+directly to the PTKSTART state since there is no need to try to
+determine the PMK again in such a case. This is far from ideal since the
+new PTK would depend on a new nonce only from the supplicant.
+
+Fix this by generating a new ANonce when moving to the PTKSTART state
+for the purpose of starting new 4-way handshake to rekey PTK.
+
+Signed-off-by: Jouni Malinen <j@w1.fi>
+---
+ src/ap/wpa_auth.c | 24 +++++++++++++++++++++---
+ 1 file changed, 21 insertions(+), 3 deletions(-)
+
+diff --git a/src/ap/wpa_auth.c b/src/ap/wpa_auth.c
+index 707971d..bf10cc1 100644
+--- a/src/ap/wpa_auth.c
++++ b/src/ap/wpa_auth.c
+@@ -1901,6 +1901,21 @@ SM_STATE(WPA_PTK, AUTHENTICATION2)
+ }
+ 
+ 
++static int wpa_auth_sm_ptk_update(struct wpa_state_machine *sm)
++{
++      if (random_get_bytes(sm->ANonce, WPA_NONCE_LEN)) {
++              wpa_printf(MSG_ERROR,
++                         "WPA: Failed to get random data for ANonce");
++              sm->Disconnect = TRUE;
++              return -1;
++      }
++      wpa_hexdump(MSG_DEBUG, "WPA: Assign new ANonce", sm->ANonce,
++                  WPA_NONCE_LEN);
++      sm->TimeoutCtr = 0;
++      return 0;
++}
++
++
+ SM_STATE(WPA_PTK, INITPMK)
+ {
+       u8 msk[2 * PMK_LEN];
+@@ -2458,9 +2473,12 @@ SM_STEP(WPA_PTK)
+               SM_ENTER(WPA_PTK, AUTHENTICATION);
+       else if (sm->ReAuthenticationRequest)
+               SM_ENTER(WPA_PTK, AUTHENTICATION2);
+-      else if (sm->PTKRequest)
+-              SM_ENTER(WPA_PTK, PTKSTART);
+-      else switch (sm->wpa_ptk_state) {
++      else if (sm->PTKRequest) {
++              if (wpa_auth_sm_ptk_update(sm) < 0)
++                      SM_ENTER(WPA_PTK, DISCONNECTED);
++              else
++                      SM_ENTER(WPA_PTK, PTKSTART);
++      } else switch (sm->wpa_ptk_state) {
+       case WPA_PTK_INITIALIZE:
+               break;
+       case WPA_PTK_DISCONNECT:
+-- 
+2.7.4
+