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=-7.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 D03C0C04EB8 for ; Thu, 6 Dec 2018 14:46:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 80BFF21479 for ; Thu, 6 Dec 2018 14:46:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544107568; bh=zIO1IHoTkfKIHBVu3iJBCqVU6FTyegkIGG4lHaUsizo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ZCrT8xYfQSFF97TvAi1Ozl2YMaiKWATwrpWKlmYq2Q1xbpfvcbUQiEn4ZtuJONGLe clgwqMcQq8LeOl9Q4Bkub08Yi+KL2MnOSxJQvQsAgIiGmBgzLlNcP5ROuO52AVphSl QPTG5+grXnRxAl4aJwlU7TjFpTSnhZAgcHPoQEzM= DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 80BFF21479 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731201AbeLFOqG (ORCPT ); Thu, 6 Dec 2018 09:46:06 -0500 Received: from mail.kernel.org ([198.145.29.99]:50786 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731189AbeLFOqE (ORCPT ); Thu, 6 Dec 2018 09:46:04 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 D206B2146D; Thu, 6 Dec 2018 14:46:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544107563; bh=zIO1IHoTkfKIHBVu3iJBCqVU6FTyegkIGG4lHaUsizo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EpFrDZ/4GlbxvO7hbx9ZdWaezeB3eWQZkDGvLUJONSWNxYsH14iNWsjTWWjZVKwMQ iYAhOyytKjQu0PrkMmuQ/AdsiTRWWYEukLxW+fX4LzkqxNQc7T0tw81ggI9AYoOYdk 59i5cIJ+mj+0eXsJrkhmyQq8mrpyrUYXX5zf+J+8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ilya Dryomov , Sage Weil , Ben Hutchings Subject: [PATCH 4.9 054/101] libceph: add authorizer challenge Date: Thu, 6 Dec 2018 15:38:53 +0100 Message-Id: <20181206143014.665403185@linuxfoundation.org> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181206143011.174892052@linuxfoundation.org> References: <20181206143011.174892052@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore 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 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ilya Dryomov commit 6daca13d2e72bedaaacfc08f873114c9307d5aea upstream. When a client authenticates with a service, an authorizer is sent with a nonce to the service (ceph_x_authorize_[ab]) and the service responds with a mutation of that nonce (ceph_x_authorize_reply). This lets the client verify the service is who it says it is but it doesn't protect against a replay: someone can trivially capture the exchange and reuse the same authorizer to authenticate themselves. Allow the service to reject an initial authorizer with a random challenge (ceph_x_authorize_challenge). The client then has to respond with an updated authorizer proving they are able to decrypt the service's challenge and that the new authorizer was produced for this specific connection instance. The accepting side requires this challenge and response unconditionally if the client side advertises they have CEPHX_V2 feature bit. This addresses CVE-2018-1128. Link: http://tracker.ceph.com/issues/24836 Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- fs/ceph/mds_client.c | 11 ++++++ include/linux/ceph/auth.h | 8 ++++ include/linux/ceph/messenger.h | 3 + include/linux/ceph/msgr.h | 2 - net/ceph/auth.c | 16 +++++++++ net/ceph/auth_x.c | 72 ++++++++++++++++++++++++++++++++++++++--- net/ceph/auth_x_protocol.h | 7 +++ net/ceph/messenger.c | 17 +++++++++ net/ceph/osd_client.c | 11 ++++++ 9 files changed, 140 insertions(+), 7 deletions(-) --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -3983,6 +3983,16 @@ static struct ceph_auth_handshake *get_a return auth; } +static int add_authorizer_challenge(struct ceph_connection *con, + void *challenge_buf, int challenge_buf_len) +{ + struct ceph_mds_session *s = con->private; + struct ceph_mds_client *mdsc = s->s_mdsc; + struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth; + + return ceph_auth_add_authorizer_challenge(ac, s->s_auth.authorizer, + challenge_buf, challenge_buf_len); +} static int verify_authorizer_reply(struct ceph_connection *con) { @@ -4046,6 +4056,7 @@ static const struct ceph_connection_oper .put = con_put, .dispatch = dispatch, .get_authorizer = get_authorizer, + .add_authorizer_challenge = add_authorizer_challenge, .verify_authorizer_reply = verify_authorizer_reply, .invalidate_authorizer = invalidate_authorizer, .peer_reset = peer_reset, --- a/include/linux/ceph/auth.h +++ b/include/linux/ceph/auth.h @@ -63,6 +63,10 @@ struct ceph_auth_client_ops { /* ensure that an existing authorizer is up to date */ int (*update_authorizer)(struct ceph_auth_client *ac, int peer_type, struct ceph_auth_handshake *auth); + int (*add_authorizer_challenge)(struct ceph_auth_client *ac, + struct ceph_authorizer *a, + void *challenge_buf, + int challenge_buf_len); int (*verify_authorizer_reply)(struct ceph_auth_client *ac, struct ceph_authorizer *a); void (*invalidate_authorizer)(struct ceph_auth_client *ac, @@ -117,6 +121,10 @@ void ceph_auth_destroy_authorizer(struct extern int ceph_auth_update_authorizer(struct ceph_auth_client *ac, int peer_type, struct ceph_auth_handshake *a); +int ceph_auth_add_authorizer_challenge(struct ceph_auth_client *ac, + struct ceph_authorizer *a, + void *challenge_buf, + int challenge_buf_len); extern int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac, struct ceph_authorizer *a); extern void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac, --- a/include/linux/ceph/messenger.h +++ b/include/linux/ceph/messenger.h @@ -30,6 +30,9 @@ struct ceph_connection_operations { struct ceph_auth_handshake *(*get_authorizer) ( struct ceph_connection *con, int *proto, int force_new); + int (*add_authorizer_challenge)(struct ceph_connection *con, + void *challenge_buf, + int challenge_buf_len); int (*verify_authorizer_reply) (struct ceph_connection *con); int (*invalidate_authorizer)(struct ceph_connection *con); --- a/include/linux/ceph/msgr.h +++ b/include/linux/ceph/msgr.h @@ -90,7 +90,7 @@ struct ceph_entity_inst { #define CEPH_MSGR_TAG_SEQ 13 /* 64-bit int follows with seen seq number */ #define CEPH_MSGR_TAG_KEEPALIVE2 14 /* keepalive2 byte + ceph_timespec */ #define CEPH_MSGR_TAG_KEEPALIVE2_ACK 15 /* keepalive2 reply */ - +#define CEPH_MSGR_TAG_CHALLENGE_AUTHORIZER 16 /* cephx v2 doing server challenge */ /* * connection negotiation --- a/net/ceph/auth.c +++ b/net/ceph/auth.c @@ -314,6 +314,22 @@ int ceph_auth_update_authorizer(struct c } EXPORT_SYMBOL(ceph_auth_update_authorizer); +int ceph_auth_add_authorizer_challenge(struct ceph_auth_client *ac, + struct ceph_authorizer *a, + void *challenge_buf, + int challenge_buf_len) +{ + int ret = 0; + + mutex_lock(&ac->mutex); + if (ac->ops && ac->ops->add_authorizer_challenge) + ret = ac->ops->add_authorizer_challenge(ac, a, challenge_buf, + challenge_buf_len); + mutex_unlock(&ac->mutex); + return ret; +} +EXPORT_SYMBOL(ceph_auth_add_authorizer_challenge); + int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac, struct ceph_authorizer *a) { --- a/net/ceph/auth_x.c +++ b/net/ceph/auth_x.c @@ -291,7 +291,8 @@ bad: * authorizer. The first part (ceph_x_authorize_a) should already be * encoded. */ -static int encrypt_authorizer(struct ceph_x_authorizer *au) +static int encrypt_authorizer(struct ceph_x_authorizer *au, + u64 *server_challenge) { struct ceph_x_authorize_a *msg_a; struct ceph_x_authorize_b *msg_b; @@ -304,16 +305,28 @@ static int encrypt_authorizer(struct cep end = au->buf->vec.iov_base + au->buf->vec.iov_len; msg_b = p + ceph_x_encrypt_offset(); - msg_b->struct_v = 1; + msg_b->struct_v = 2; msg_b->nonce = cpu_to_le64(au->nonce); + if (server_challenge) { + msg_b->have_challenge = 1; + msg_b->server_challenge_plus_one = + cpu_to_le64(*server_challenge + 1); + } else { + msg_b->have_challenge = 0; + msg_b->server_challenge_plus_one = 0; + } ret = ceph_x_encrypt(&au->session_key, p, end - p, sizeof(*msg_b)); if (ret < 0) return ret; p += ret; - WARN_ON(p > end); - au->buf->vec.iov_len = p - au->buf->vec.iov_base; + if (server_challenge) { + WARN_ON(p != end); + } else { + WARN_ON(p > end); + au->buf->vec.iov_len = p - au->buf->vec.iov_base; + } return 0; } @@ -378,7 +391,7 @@ static int ceph_x_build_authorizer(struc le64_to_cpu(msg_a->ticket_blob.secret_id)); get_random_bytes(&au->nonce, sizeof(au->nonce)); - ret = encrypt_authorizer(au); + ret = encrypt_authorizer(au, NULL); if (ret) { pr_err("failed to encrypt authorizer: %d", ret); goto out_au; @@ -660,6 +673,54 @@ static int ceph_x_update_authorizer( return 0; } +static int decrypt_authorize_challenge(struct ceph_x_authorizer *au, + void *challenge_buf, + int challenge_buf_len, + u64 *server_challenge) +{ + struct ceph_x_authorize_challenge *ch = + challenge_buf + sizeof(struct ceph_x_encrypt_header); + int ret; + + /* no leading len */ + ret = __ceph_x_decrypt(&au->session_key, challenge_buf, + challenge_buf_len); + if (ret < 0) + return ret; + if (ret < sizeof(*ch)) { + pr_err("bad size %d for ceph_x_authorize_challenge\n", ret); + return -EINVAL; + } + + *server_challenge = le64_to_cpu(ch->server_challenge); + return 0; +} + +static int ceph_x_add_authorizer_challenge(struct ceph_auth_client *ac, + struct ceph_authorizer *a, + void *challenge_buf, + int challenge_buf_len) +{ + struct ceph_x_authorizer *au = (void *)a; + u64 server_challenge; + int ret; + + ret = decrypt_authorize_challenge(au, challenge_buf, challenge_buf_len, + &server_challenge); + if (ret) { + pr_err("failed to decrypt authorize challenge: %d", ret); + return ret; + } + + ret = encrypt_authorizer(au, &server_challenge); + if (ret) { + pr_err("failed to encrypt authorizer w/ challenge: %d", ret); + return ret; + } + + return 0; +} + static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac, struct ceph_authorizer *a) { @@ -812,6 +873,7 @@ static const struct ceph_auth_client_ops .handle_reply = ceph_x_handle_reply, .create_authorizer = ceph_x_create_authorizer, .update_authorizer = ceph_x_update_authorizer, + .add_authorizer_challenge = ceph_x_add_authorizer_challenge, .verify_authorizer_reply = ceph_x_verify_authorizer_reply, .invalidate_authorizer = ceph_x_invalidate_authorizer, .reset = ceph_x_reset, --- a/net/ceph/auth_x_protocol.h +++ b/net/ceph/auth_x_protocol.h @@ -69,6 +69,13 @@ struct ceph_x_authorize_a { struct ceph_x_authorize_b { __u8 struct_v; __le64 nonce; + __u8 have_challenge; + __le64 server_challenge_plus_one; +} __attribute__ ((packed)); + +struct ceph_x_authorize_challenge { + __u8 struct_v; + __le64 server_challenge; } __attribute__ ((packed)); struct ceph_x_authorize_reply { --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -2037,9 +2037,24 @@ static int process_connect(struct ceph_c if (con->auth) { /* * Any connection that defines ->get_authorizer() - * should also define ->verify_authorizer_reply(). + * should also define ->add_authorizer_challenge() and + * ->verify_authorizer_reply(). + * * See get_connect_authorizer(). */ + if (con->in_reply.tag == CEPH_MSGR_TAG_CHALLENGE_AUTHORIZER) { + ret = con->ops->add_authorizer_challenge( + con, con->auth->authorizer_reply_buf, + le32_to_cpu(con->in_reply.authorizer_len)); + if (ret < 0) + return ret; + + con_out_kvec_reset(con); + __prepare_write_connect(con); + prepare_read_connect(con); + return 0; + } + ret = con->ops->verify_authorizer_reply(con); if (ret < 0) { con->error_msg = "bad authorize reply"; --- a/net/ceph/osd_client.c +++ b/net/ceph/osd_client.c @@ -4478,6 +4478,16 @@ static struct ceph_auth_handshake *get_a return auth; } +static int add_authorizer_challenge(struct ceph_connection *con, + void *challenge_buf, int challenge_buf_len) +{ + struct ceph_osd *o = con->private; + struct ceph_osd_client *osdc = o->o_osdc; + struct ceph_auth_client *ac = osdc->client->monc.auth; + + return ceph_auth_add_authorizer_challenge(ac, o->o_auth.authorizer, + challenge_buf, challenge_buf_len); +} static int verify_authorizer_reply(struct ceph_connection *con) { @@ -4519,6 +4529,7 @@ static const struct ceph_connection_oper .put = put_osd_con, .dispatch = dispatch, .get_authorizer = get_authorizer, + .add_authorizer_challenge = add_authorizer_challenge, .verify_authorizer_reply = verify_authorizer_reply, .invalidate_authorizer = invalidate_authorizer, .alloc_msg = alloc_msg,