From patchwork Fri Jan 8 09:52:40 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huw Davies X-Patchwork-Id: 564684 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 8C1291402A8 for ; Fri, 8 Jan 2016 20:53:55 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=codeweavers.com header.i=@codeweavers.com header.b=TYlBM8sq; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754521AbcAHJxo (ORCPT ); Fri, 8 Jan 2016 04:53:44 -0500 Received: from mail.codeweavers.com ([216.251.189.131]:38436 "EHLO mail.codeweavers.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754443AbcAHJxS (ORCPT ); Fri, 8 Jan 2016 04:53:18 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=codeweavers.com; s=6377696661; h=Message-Id:Date:Subject:Cc:To:From; bh=itk21MM57IEQy9ohelyEeen3zuIoQnpdp2SCB5cJGQQ=; b=TYlBM8sq0CO+iHX3NIQGHGl02/8ROLEwhKzSjaae3QtZHpSXfm7aB/ehzI2fxRwzyeIg4Xls4nQ7nYG6WOKCiB6JHdm9S5neJ9YpWx3n4jMcMmq1X2/F9rwTZT+zlGXq83ZNo8/BYYUsV3bwA1ey8/N8cCEVkXAORncStZrR/Nw=; Received: from merlot.physics.ox.ac.uk ([163.1.241.98]) by mail.codeweavers.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1aHTjQ-00069N-71; Fri, 08 Jan 2016 03:53:17 -0600 Received: from daviesh by merlot.physics.ox.ac.uk with local (Exim 4.71) (envelope-from ) id 1aHTj5-0003ex-SZ; Fri, 08 Jan 2016 09:52:55 +0000 From: Huw Davies To: netdev@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@tycho.nsa.gov Cc: Paul Moore Subject: [RFC PATCH v2 04/18] netlabel: Add support for querying a CALIPSO DOI. Date: Fri, 8 Jan 2016 09:52:40 +0000 Message-Id: <1452246774-13241-5-git-send-email-huw@codeweavers.com> X-Mailer: git-send-email 1.8.0 X-Spam-Score: -2.9 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Query a specified DOI through the NLBL_CALIPSO_C_LIST command. It requires the attribute: NLBL_CALIPSO_A_DOI. The reply will contain: NLBL_CALIPSO_A_MTYPE Signed-off-by: Huw Davies --- include/net/netlabel.h | 4 ++ net/ipv6/calipso.c | 68 +++++++++++++++++++++++++++ net/netlabel/netlabel_calipso.c | 102 ++++++++++++++++++++++++++++++++++++++++ net/netlabel/netlabel_calipso.h | 2 + 4 files changed, 176 insertions(+) diff --git a/include/net/netlabel.h b/include/net/netlabel.h index 6af1bb6..0f05b83 100644 --- a/include/net/netlabel.h +++ b/include/net/netlabel.h @@ -223,6 +223,8 @@ struct netlbl_lsm_secattr { * struct netlbl_calipso_ops - NetLabel CALIPSO operations * @doi_add: add a CALIPSO DOI * @doi_free: free a CALIPSO DOI + * @doi_getdef: returns a reference to a DOI + * @doi_putdef: releases a reference of a DOI * * Description: * This structure is filled out by the CALIPSO engine and passed @@ -234,6 +236,8 @@ struct netlbl_calipso_ops { int (*doi_add)(struct calipso_doi *doi_def, struct netlbl_audit *audit_info); void (*doi_free)(struct calipso_doi *doi_def); + struct calipso_doi *(*doi_getdef)(u32 doi); + void (*doi_putdef)(struct calipso_doi *doi_def); }; /* diff --git a/net/ipv6/calipso.c b/net/ipv6/calipso.c index aa44310..128cc69 100644 --- a/net/ipv6/calipso.c +++ b/net/ipv6/calipso.c @@ -144,9 +144,77 @@ static void calipso_doi_free(struct calipso_doi *doi_def) kfree(doi_def); } +/** + * calipso_doi_free_rcu - Frees a DOI definition via the RCU pointer + * @entry: the entry's RCU field + * + * Description: + * This function is designed to be used as a callback to the call_rcu() + * function so that the memory allocated to the DOI definition can be released + * safely. + * + */ +static void calipso_doi_free_rcu(struct rcu_head *entry) +{ + struct calipso_doi *doi_def; + + doi_def = container_of(entry, struct calipso_doi, rcu); + calipso_doi_free(doi_def); +} + +/** + * calipso_doi_getdef - Returns a reference to a valid DOI definition + * @doi: the DOI value + * + * Description: + * Searches for a valid DOI definition and if one is found it is returned to + * the caller. Otherwise NULL is returned. The caller must ensure that + * calipso_doi_putdef() is called when the caller is done. + * + */ +static struct calipso_doi *calipso_doi_getdef(u32 doi) +{ + struct calipso_doi *doi_def; + + rcu_read_lock(); + doi_def = calipso_doi_search(doi); + if (!doi_def) + goto doi_getdef_return; + if (!atomic_inc_not_zero(&doi_def->refcount)) + doi_def = NULL; + +doi_getdef_return: + rcu_read_unlock(); + return doi_def; +} + +/** + * calipso_doi_putdef - Releases a reference for the given DOI definition + * @doi_def: the DOI definition + * + * Description: + * Releases a DOI definition reference obtained from calipso_doi_getdef(). + * + */ +static void calipso_doi_putdef(struct calipso_doi *doi_def) +{ + if (!doi_def) + return; + + if (!atomic_dec_and_test(&doi_def->refcount)) + return; + spin_lock(&calipso_doi_list_lock); + list_del_rcu(&doi_def->list); + spin_unlock(&calipso_doi_list_lock); + + call_rcu(&doi_def->rcu, calipso_doi_free_rcu); +} + static const struct netlbl_calipso_ops ops = { .doi_add = calipso_doi_add, .doi_free = calipso_doi_free, + .doi_getdef = calipso_doi_getdef, + .doi_putdef = calipso_doi_putdef, }; /** diff --git a/net/netlabel/netlabel_calipso.c b/net/netlabel/netlabel_calipso.c index ccf8536..81faafa 100644 --- a/net/netlabel/netlabel_calipso.c +++ b/net/netlabel/netlabel_calipso.c @@ -128,6 +128,65 @@ static int netlbl_calipso_add(struct sk_buff *skb, struct genl_info *info) return ret_val; } +/** + * netlbl_calipso_list - Handle a LIST message + * @skb: the NETLINK buffer + * @info: the Generic NETLINK info block + * + * Description: + * Process a user generated LIST message and respond accordingly. + * Returns zero on success and negative values on error. + * + */ +static int netlbl_calipso_list(struct sk_buff *skb, struct genl_info *info) +{ + int ret_val; + struct sk_buff *ans_skb = NULL; + void *data; + u32 doi; + struct calipso_doi *doi_def; + + if (!info->attrs[NLBL_CALIPSO_A_DOI]) { + ret_val = -EINVAL; + goto list_failure; + } + + doi = nla_get_u32(info->attrs[NLBL_CALIPSO_A_DOI]); + + doi_def = calipso_doi_getdef(doi); + if (!doi_def) { + ret_val = -EINVAL; + goto list_failure; + } + + ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!ans_skb) { + ret_val = -ENOMEM; + goto list_failure_put; + } + data = genlmsg_put_reply(ans_skb, info, &netlbl_calipso_gnl_family, + 0, NLBL_CALIPSO_C_LIST); + if (!data) { + ret_val = -ENOMEM; + goto list_failure_put; + } + + ret_val = nla_put_u32(ans_skb, NLBL_CALIPSO_A_MTYPE, doi_def->type); + if (ret_val != 0) + goto list_failure_put; + + calipso_doi_putdef(doi_def); + + genlmsg_end(ans_skb, data); + return genlmsg_reply(ans_skb, info); + +list_failure_put: + calipso_doi_putdef(doi_def); +list_failure: + kfree_skb(ans_skb); + return ret_val; +} + /* NetLabel Generic NETLINK Command Definitions */ @@ -139,6 +198,13 @@ static const struct genl_ops netlbl_calipso_ops[] = { .doit = netlbl_calipso_add, .dumpit = NULL, }, + { + .cmd = NLBL_CALIPSO_C_LIST, + .flags = 0, + .policy = calipso_genl_policy, + .doit = netlbl_calipso_list, + .dumpit = NULL, + }, }; /* NetLabel Generic NETLINK Protocol Functions @@ -218,3 +284,39 @@ void calipso_doi_free(struct calipso_doi *doi_def) if (ops) ops->doi_free(doi_def); } + +/** + * calipso_doi_getdef - Returns a reference to a valid DOI definition + * @doi: the DOI value + * + * Description: + * Searches for a valid DOI definition and if one is found it is returned to + * the caller. Otherwise NULL is returned. The caller must ensure that + * calipso_doi_putdef() is called when the caller is done. + * + */ +struct calipso_doi *calipso_doi_getdef(u32 doi) +{ + struct calipso_doi *ret_val = NULL; + const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); + + if (ops) + ret_val = ops->doi_getdef(doi); + return ret_val; +} + +/** + * calipso_doi_putdef - Releases a reference for the given DOI definition + * @doi_def: the DOI definition + * + * Description: + * Releases a DOI definition reference obtained from calipso_doi_getdef(). + * + */ +void calipso_doi_putdef(struct calipso_doi *doi_def) +{ + const struct netlbl_calipso_ops *ops = netlbl_calipso_ops_get(); + + if (ops) + ops->doi_putdef(doi_def); +} diff --git a/net/netlabel/netlabel_calipso.h b/net/netlabel/netlabel_calipso.h index 01bfd37..6cf1cad 100644 --- a/net/netlabel/netlabel_calipso.h +++ b/net/netlabel/netlabel_calipso.h @@ -124,5 +124,7 @@ static inline int netlbl_calipso_genl_init(void) int calipso_doi_add(struct calipso_doi *doi_def, struct netlbl_audit *audit_info); void calipso_doi_free(struct calipso_doi *doi_def); +struct calipso_doi *calipso_doi_getdef(u32 doi); +void calipso_doi_putdef(struct calipso_doi *doi_def); #endif