From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8CAEFC04AAC for ; Mon, 20 May 2019 12:32:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62808216E3 for ; Mon, 20 May 2019 12:32:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558355539; bh=vV9sTrOCaTdUOl0QS35EQWcamzFZWUZMgVjxVr+EvPY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=d3Pj90KTvQcFSGeV19FoNevfR8w6tcseoxvjsYUGyalvA+gb0TCSkpJFG2QfHNlEp lLAkv5WMa9rc39lfeTI8Ygng4SPKBvwTPC55u/93fKQDzcxPZWVbfmfswONon0qvWt u9JmbeA8lvR0f9ukj4febVDL2ZJdyhZN+UTNBWLI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390528AbfETMcR (ORCPT ); Mon, 20 May 2019 08:32:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:49048 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390505AbfETMcP (ORCPT ); Mon, 20 May 2019 08:32:15 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1287521726; Mon, 20 May 2019 12:32:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558355534; bh=vV9sTrOCaTdUOl0QS35EQWcamzFZWUZMgVjxVr+EvPY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kIsBELX910ccYp6lQqBWewFnVQqOIeE5Dvl/lled6iqkkLHTdFZX8abFz/O+fX/KA ZoiiBxd3N+/LyZM28lolDZZnQGKffNlpWNXNsaTx8/L1KaQqNzPZooW/ufXYqJfNK2 9bQVPgjhhvRWktRX7lzb2w7FMj4rll1ixUBWtgFk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , Herbert Xu Subject: [PATCH 5.1 029/128] crypto: ccm - fix incompatibility between "ccm" and "ccm_base" Date: Mon, 20 May 2019 14:13:36 +0200 Message-Id: <20190520115251.595811679@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190520115249.449077487@linuxfoundation.org> References: <20190520115249.449077487@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Biggers commit 6a1faa4a43f5fabf9cbeaa742d916e7b5e73120f upstream. CCM instances can be created by either the "ccm" template, which only allows choosing the block cipher, e.g. "ccm(aes)"; or by "ccm_base", which allows choosing the ctr and cbcmac implementations, e.g. "ccm_base(ctr(aes-generic),cbcmac(aes-generic))". However, a "ccm_base" instance prevents a "ccm" instance from being registered using the same implementations. Nor will the instance be found by lookups of "ccm". This can be used as a denial of service. Moreover, "ccm_base" instances are never tested by the crypto self-tests, even if there are compatible "ccm" tests. The root cause of these problems is that instances of the two templates use different cra_names. Therefore, fix these problems by making "ccm_base" instances set the same cra_name as "ccm" instances, e.g. "ccm(aes)" instead of "ccm_base(ctr(aes-generic),cbcmac(aes-generic))". This requires extracting the block cipher name from the name of the ctr and cbcmac algorithms. It also requires starting to verify that the algorithms are really ctr and cbcmac using the same block cipher, not something else entirely. But it would be bizarre if anyone were actually using non-ccm-compatible algorithms with ccm_base, so this shouldn't break anyone in practice. Fixes: 4a49b499dfa0 ("[CRYPTO] ccm: Added CCM mode") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/ccm.c | 44 ++++++++++++++++++-------------------------- 1 file changed, 18 insertions(+), 26 deletions(-) --- a/crypto/ccm.c +++ b/crypto/ccm.c @@ -458,7 +458,6 @@ static void crypto_ccm_free(struct aead_ static int crypto_ccm_create_common(struct crypto_template *tmpl, struct rtattr **tb, - const char *full_name, const char *ctr_name, const char *mac_name) { @@ -486,7 +485,8 @@ static int crypto_ccm_create_common(stru mac = __crypto_hash_alg_common(mac_alg); err = -EINVAL; - if (mac->digestsize != 16) + if (strncmp(mac->base.cra_name, "cbcmac(", 7) != 0 || + mac->digestsize != 16) goto out_put_mac; inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL); @@ -509,23 +509,27 @@ static int crypto_ccm_create_common(stru ctr = crypto_spawn_skcipher_alg(&ictx->ctr); - /* Not a stream cipher? */ + /* The skcipher algorithm must be CTR mode, using 16-byte blocks. */ err = -EINVAL; - if (ctr->base.cra_blocksize != 1) + if (strncmp(ctr->base.cra_name, "ctr(", 4) != 0 || + crypto_skcipher_alg_ivsize(ctr) != 16 || + ctr->base.cra_blocksize != 1) goto err_drop_ctr; - /* We want the real thing! */ - if (crypto_skcipher_alg_ivsize(ctr) != 16) + /* ctr and cbcmac must use the same underlying block cipher. */ + if (strcmp(ctr->base.cra_name + 4, mac->base.cra_name + 7) != 0) goto err_drop_ctr; err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "ccm(%s", ctr->base.cra_name + 4) >= CRYPTO_MAX_ALG_NAME) + goto err_drop_ctr; + if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)", ctr->base.cra_driver_name, mac->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) goto err_drop_ctr; - memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME); - inst->alg.base.cra_flags = ctr->base.cra_flags & CRYPTO_ALG_ASYNC; inst->alg.base.cra_priority = (mac->base.cra_priority + ctr->base.cra_priority) / 2; @@ -567,7 +571,6 @@ static int crypto_ccm_create(struct cryp const char *cipher_name; char ctr_name[CRYPTO_MAX_ALG_NAME]; char mac_name[CRYPTO_MAX_ALG_NAME]; - char full_name[CRYPTO_MAX_ALG_NAME]; cipher_name = crypto_attr_alg_name(tb[1]); if (IS_ERR(cipher_name)) @@ -581,35 +584,24 @@ static int crypto_ccm_create(struct cryp cipher_name) >= CRYPTO_MAX_ALG_NAME) return -ENAMETOOLONG; - if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm(%s)", cipher_name) >= - CRYPTO_MAX_ALG_NAME) - return -ENAMETOOLONG; - - return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name, - mac_name); + return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name); } static int crypto_ccm_base_create(struct crypto_template *tmpl, struct rtattr **tb) { const char *ctr_name; - const char *cipher_name; - char full_name[CRYPTO_MAX_ALG_NAME]; + const char *mac_name; ctr_name = crypto_attr_alg_name(tb[1]); if (IS_ERR(ctr_name)) return PTR_ERR(ctr_name); - cipher_name = crypto_attr_alg_name(tb[2]); - if (IS_ERR(cipher_name)) - return PTR_ERR(cipher_name); - - if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "ccm_base(%s,%s)", - ctr_name, cipher_name) >= CRYPTO_MAX_ALG_NAME) - return -ENAMETOOLONG; + mac_name = crypto_attr_alg_name(tb[2]); + if (IS_ERR(mac_name)) + return PTR_ERR(mac_name); - return crypto_ccm_create_common(tmpl, tb, full_name, ctr_name, - cipher_name); + return crypto_ccm_create_common(tmpl, tb, ctr_name, mac_name); } static int crypto_rfc4309_setkey(struct crypto_aead *parent, const u8 *key,