From patchwork Sat Jun 10 02:59:12 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 9779631 X-Patchwork-Delegate: johannes@sipsolutions.net Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0151E60393 for ; Sat, 10 Jun 2017 03:00:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E728028556 for ; Sat, 10 Jun 2017 03:00:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id DBCA2285A6; Sat, 10 Jun 2017 03:00:14 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 66E8E28556 for ; Sat, 10 Jun 2017 03:00:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751885AbdFJC7u (ORCPT ); Fri, 9 Jun 2017 22:59:50 -0400 Received: from frisell.zx2c4.com ([192.95.5.64]:52679 "EHLO frisell.zx2c4.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751861AbdFJC7i (ORCPT ); Fri, 9 Jun 2017 22:59:38 -0400 Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 5065813a; Sat, 10 Jun 2017 02:58:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=zx2c4.com; h=from:to:cc :subject:date:message-id:in-reply-to:references; s=mail; bh=HTha 5DRDvk9Slu1r5CVH+pzMbIg=; b=vi3F/4/2VSiHkavwzanPO/YmExWIf/J9+QmN 2unkcvSVd5RwZlqvOoJHtMaXXtLucFQMHHt3bHZjuH1FufEW6M8bxgpjZ2ceo3xp 7Phjq56LpAWpK6+HmS3F7ThDQncCyKTpOGvS4BTcMN9lkfXBCkULa7Z4wh5BoBex 9N0aMHBHKd/5En6z1DLBnDbgtT+F0VP1NvDQFJFzyWOazksZdTn8AOs4D1IbaDz6 VmEHiCq+0c0dxXQx6vq/D6hQqCSNFdsPoQBVhOHlBghoI3BS0Gy7gLxbxGQwwn6z bs1Ae/mxXUZkipVInEmT7TxvKLGerqJnHDwamWBbJqrrvKtHOw== Received: by frisell.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id e5ded30e (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256:NO); Sat, 10 Jun 2017 02:58:47 +0000 (UTC) From: "Jason A. Donenfeld" To: linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com Cc: "Jason A. Donenfeld" , Johannes Berg , linux-wireless@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH 6/6] mac80211/wpa: use constant time memory comparison for MACs Date: Sat, 10 Jun 2017 04:59:12 +0200 Message-Id: <20170610025912.6499-7-Jason@zx2c4.com> In-Reply-To: <20170610025912.6499-1-Jason@zx2c4.com> References: <20170610025912.6499-1-Jason@zx2c4.com> Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Otherwise, we enable all sorts of forgeries via timing attack. Signed-off-by: Jason A. Donenfeld Cc: Johannes Berg Cc: linux-wireless@vger.kernel.org Cc: stable@vger.kernel.org --- net/mac80211/wpa.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c index c1ef22df865f..cc19614ff4e6 100644 --- a/net/mac80211/wpa.c +++ b/net/mac80211/wpa.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "ieee80211_i.h" #include "michael.h" @@ -153,7 +154,7 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx) data_len = skb->len - hdrlen - MICHAEL_MIC_LEN; key = &rx->key->conf.key[NL80211_TKIP_DATA_OFFSET_RX_MIC_KEY]; michael_mic(key, hdr, data, data_len, mic); - if (memcmp(mic, data + data_len, MICHAEL_MIC_LEN) != 0) + if (crypto_memneq(mic, data + data_len, MICHAEL_MIC_LEN)) goto mic_fail; /* remove Michael MIC from payload */ @@ -1048,7 +1049,7 @@ ieee80211_crypto_aes_cmac_decrypt(struct ieee80211_rx_data *rx) bip_aad(skb, aad); ieee80211_aes_cmac(key->u.aes_cmac.tfm, aad, skb->data + 24, skb->len - 24, mic); - if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { + if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { key->u.aes_cmac.icverrors++; return RX_DROP_UNUSABLE; } @@ -1098,7 +1099,7 @@ ieee80211_crypto_aes_cmac_256_decrypt(struct ieee80211_rx_data *rx) bip_aad(skb, aad); ieee80211_aes_cmac_256(key->u.aes_cmac.tfm, aad, skb->data + 24, skb->len - 24, mic); - if (memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { + if (crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { key->u.aes_cmac.icverrors++; return RX_DROP_UNUSABLE; } @@ -1202,7 +1203,7 @@ ieee80211_crypto_aes_gmac_decrypt(struct ieee80211_rx_data *rx) if (ieee80211_aes_gmac(key->u.aes_gmac.tfm, aad, nonce, skb->data + 24, skb->len - 24, mic) < 0 || - memcmp(mic, mmie->mic, sizeof(mmie->mic)) != 0) { + crypto_memneq(mic, mmie->mic, sizeof(mmie->mic))) { key->u.aes_gmac.icverrors++; return RX_DROP_UNUSABLE; }