From f997816a7f5dc00d1a91e5b4fb9e932a3f64af06 Mon Sep 17 00:00:00 2001 From: Denis Kenzior Date: Tue, 24 Feb 2015 11:14:11 -0600 Subject: [PATCH] eapol: Handle Step 2 & 4 of the 4-way Handshake --- src/eapol.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/src/eapol.c b/src/eapol.c index 1b70e186..20fa6246 100644 --- a/src/eapol.c +++ b/src/eapol.c @@ -527,6 +527,54 @@ fail: l_free(step2); } +static void eapol_handle_ptk_3_of_4(int ifindex, struct eapol_sm *sm, + const struct eapol_key *ek, + const uint8_t *decrypted_key_data) +{ + struct crypto_ptk *ptk = (struct crypto_ptk *) sm->ptk; + struct eapol_key *step4; + uint8_t mic[16]; + + if (!eapol_verify_ptk_3_of_4(ek)) + return; + + /* + * 11.6.6.4: "On reception of Message 3, the Supplicant silently + * discards the message if ... or if the ANonce value in Message 3 + * differs from the ANonce value in Message 1" + */ + if (memcmp(sm->anonce, ek->key_nonce, sizeof(ek->key_nonce))) + return; + + /* + * TODO: Check that first RSNE matches ap_rsne + * 11.6.6.4: "Verifies the RSNE. If it is part of a Fast BSS Transition + * Initial Mobility Domain Association, see 12.4.2. Otherwise, if it is + * not identical to that the STA received in the Beacon or Probe + * Response frame, the STA shall disassociate. + */ + + /* + * TODO: Parse second RSNE + * 11.6.6.4: "If a second RSNE is provided in the message, the + * Supplicant uses the pairwise cipher suite specified in the second + * RSNE or deauthenticates." + */ + step4 = eapol_create_ptk_4_of_4(protocol_version, + ek->key_descriptor_version, + sm->replay_counter); + + if (!eapol_calculate_mic(ptk->kck, step4, mic)) + goto fail; + + memcpy(step4->key_mic_data, mic, sizeof(mic)); + tx_packet(ifindex, sm->aa_addr, sm->sta_addr, step4); + +fail: + l_free(step4); + +} + void __eapol_rx_packet(int ifindex, const uint8_t *sta_addr, const uint8_t *aa_addr, const uint8_t *frame, size_t len)