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=-23.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 6C12AC54F5D for ; Sat, 12 Dec 2020 01:01:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5598023770 for ; Sat, 12 Dec 2020 01:01:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2437643AbgLLAKD (ORCPT ); Fri, 11 Dec 2020 19:10:03 -0500 Received: from linux.microsoft.com ([13.77.154.182]:56186 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2395019AbgLLAJj (ORCPT ); Fri, 11 Dec 2020 19:09:39 -0500 Received: from sequoia (162-237-133-238.lightspeed.rcsntx.sbcglobal.net [162.237.133.238]) by linux.microsoft.com (Postfix) with ESMTPSA id AA20620B717A; Fri, 11 Dec 2020 16:08:56 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com AA20620B717A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1607731737; bh=66clC6q+FQh1q4GDtxp3zCQtsoH4FNwuQK7hOdUU4UA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JIurpb9AQI04elmBV1GAbpIBHPvM/luA66LhOvM5zMTFQoMjbAhtXZGXzt9M3BxXF KzmJCvZ2KvJegVIcB0ugQvaywLTVyIxTfb+hPgzP7gBjPc9vuB3+y8yKGLPOnv9Wg8 New88EQdDQakKMi8OZm5cW5Y/MG3R3DnozyF/3+E= Date: Fri, 11 Dec 2020 18:08:54 -0600 From: Tyler Hicks To: Tushar Sugandhi Cc: zohar@linux.ibm.com, stephen.smalley.work@gmail.com, casey@schaufler-ca.com, agk@redhat.com, snitzer@redhat.com, gmazyland@gmail.com, paul@paul-moore.com, sashal@kernel.org, jmorris@namei.org, nramas@linux.microsoft.com, linux-integrity@vger.kernel.org, selinux@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, dm-devel@redhat.com Subject: Re: [PATCH v8 1/8] IMA: generalize keyring specific measurement constructs Message-ID: <20201212000854.GC4951@sequoia> References: <20201211235807.30815-1-tusharsu@linux.microsoft.com> <20201211235807.30815-2-tusharsu@linux.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201211235807.30815-2-tusharsu@linux.microsoft.com> Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On 2020-12-11 15:58:00, Tushar Sugandhi wrote: > IMA functions such as ima_match_keyring(), process_buffer_measurement(), > ima_match_policy() etc. handle data specific to keyrings. Currently, > these constructs are not generic to handle any func specific data. > This makes it harder to extend them without code duplication. > > Refactor the keyring specific measurement constructs to be generic and > reusable in other measurement scenarios. > > Signed-off-by: Tushar Sugandhi > Reviewed-by: Tyler Hicks This looks good to me. Thanks! Tyler > --- > security/integrity/ima/ima.h | 6 ++-- > security/integrity/ima/ima_api.c | 6 ++-- > security/integrity/ima/ima_main.c | 6 ++-- > security/integrity/ima/ima_policy.c | 46 ++++++++++++++++++----------- > 4 files changed, 37 insertions(+), 27 deletions(-) > > diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h > index 8e8b1e3cb847..e5622ce8cbb1 100644 > --- a/security/integrity/ima/ima.h > +++ b/security/integrity/ima/ima.h > @@ -256,7 +256,7 @@ static inline void ima_process_queued_keys(void) {} > int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, > int mask, enum ima_hooks func, int *pcr, > struct ima_template_desc **template_desc, > - const char *keyring); > + const char *func_data); > int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func); > int ima_collect_measurement(struct integrity_iint_cache *iint, > struct file *file, void *buf, loff_t size, > @@ -268,7 +268,7 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file, > struct ima_template_desc *template_desc); > void process_buffer_measurement(struct inode *inode, const void *buf, int size, > const char *eventname, enum ima_hooks func, > - int pcr, const char *keyring); > + int pcr, const char *func_data); > void ima_audit_measurement(struct integrity_iint_cache *iint, > const unsigned char *filename); > int ima_alloc_init_template(struct ima_event_data *event_data, > @@ -284,7 +284,7 @@ const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); > int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, > enum ima_hooks func, int mask, int flags, int *pcr, > struct ima_template_desc **template_desc, > - const char *keyring); > + const char *func_data); > void ima_init_policy(void); > void ima_update_policy(void); > void ima_update_policy_flag(void); > diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c > index 4f39fb93f278..af218babd198 100644 > --- a/security/integrity/ima/ima_api.c > +++ b/security/integrity/ima/ima_api.c > @@ -170,7 +170,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename, > * @func: caller identifier > * @pcr: pointer filled in if matched measure policy sets pcr= > * @template_desc: pointer filled in if matched measure policy sets template= > - * @keyring: keyring name used to determine the action > + * @func_data: private data specific to @func, can be NULL. > * > * The policy is defined in terms of keypairs: > * subj=, obj=, type=, func=, mask=, fsmagic= > @@ -186,14 +186,14 @@ void ima_add_violation(struct file *file, const unsigned char *filename, > int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, > int mask, enum ima_hooks func, int *pcr, > struct ima_template_desc **template_desc, > - const char *keyring) > + const char *func_data) > { > int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE | IMA_HASH; > > flags &= ima_policy_flag; > > return ima_match_policy(inode, cred, secid, func, mask, flags, pcr, > - template_desc, keyring); > + template_desc, func_data); > } > > /* > diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c > index 68956e884403..e76ef4bfd0f4 100644 > --- a/security/integrity/ima/ima_main.c > +++ b/security/integrity/ima/ima_main.c > @@ -786,13 +786,13 @@ int ima_post_load_data(char *buf, loff_t size, > * @eventname: event name to be used for the buffer entry. > * @func: IMA hook > * @pcr: pcr to extend the measurement > - * @keyring: keyring name to determine the action to be performed > + * @func_data: private data specific to @func, can be NULL. > * > * Based on policy, the buffer is measured into the ima log. > */ > void process_buffer_measurement(struct inode *inode, const void *buf, int size, > const char *eventname, enum ima_hooks func, > - int pcr, const char *keyring) > + int pcr, const char *func_data) > { > int ret = 0; > const char *audit_cause = "ENOMEM"; > @@ -831,7 +831,7 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size, > if (func) { > security_task_getsecid(current, &secid); > action = ima_get_action(inode, current_cred(), secid, 0, func, > - &pcr, &template, keyring); > + &pcr, &template, func_data); > if (!(action & IMA_MEASURE)) > return; > } > diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c > index 823a0c1379cb..a09d1a41a290 100644 > --- a/security/integrity/ima/ima_policy.c > +++ b/security/integrity/ima/ima_policy.c > @@ -453,30 +453,41 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event, > } > > /** > - * ima_match_keyring - determine whether the keyring matches the measure rule > - * @rule: a pointer to a rule > - * @keyring: name of the keyring to match against the measure rule > + * ima_match_rule_data - determine whether the given func_data matches > + * the measure rule data > + * @rule: IMA policy rule > + * @func_data: data to match against the measure rule data > * @cred: a pointer to a credentials structure for user validation > * > - * Returns true if keyring matches one in the rule, false otherwise. > + * Returns true if func_data matches one in the rule, false otherwise. > */ > -static bool ima_match_keyring(struct ima_rule_entry *rule, > - const char *keyring, const struct cred *cred) > +static bool ima_match_rule_data(struct ima_rule_entry *rule, > + const char *func_data, > + const struct cred *cred) > { > + const struct ima_rule_opt_list *opt_list = NULL; > bool matched = false; > size_t i; > > if ((rule->flags & IMA_UID) && !rule->uid_op(cred->uid, rule->uid)) > return false; > > - if (!rule->keyrings) > - return true; > + switch (rule->func) { > + case KEY_CHECK: > + if (!rule->keyrings) > + return true; > + > + opt_list = rule->keyrings; > + break; > + default: > + return false; > + } > > - if (!keyring) > + if (!func_data) > return false; > > - for (i = 0; i < rule->keyrings->count; i++) { > - if (!strcmp(rule->keyrings->items[i], keyring)) { > + for (i = 0; i < opt_list->count; i++) { > + if (!strcmp(opt_list->items[i], func_data)) { > matched = true; > break; > } > @@ -493,20 +504,20 @@ static bool ima_match_keyring(struct ima_rule_entry *rule, > * @secid: the secid of the task to be validated > * @func: LIM hook identifier > * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC) > - * @keyring: keyring name to check in policy for KEY_CHECK func > + * @func_data: private data specific to @func, can be NULL. > * > * Returns true on rule match, false on failure. > */ > static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode, > const struct cred *cred, u32 secid, > enum ima_hooks func, int mask, > - const char *keyring) > + const char *func_data) > { > int i; > > if (func == KEY_CHECK) { > return (rule->flags & IMA_FUNC) && (rule->func == func) && > - ima_match_keyring(rule, keyring, cred); > + ima_match_rule_data(rule, func_data, cred); > } > if ((rule->flags & IMA_FUNC) && > (rule->func != func && func != POST_SETATTR)) > @@ -610,8 +621,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func) > * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC) > * @pcr: set the pcr to extend > * @template_desc: the template that should be used for this rule > - * @keyring: the keyring name, if given, to be used to check in the policy. > - * keyring can be NULL if func is anything other than KEY_CHECK. > + * @func_data: private data specific to @func, can be NULL. > * > * Measure decision based on func/mask/fsmagic and LSM(subj/obj/type) > * conditions. > @@ -623,7 +633,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func) > int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, > enum ima_hooks func, int mask, int flags, int *pcr, > struct ima_template_desc **template_desc, > - const char *keyring) > + const char *func_data) > { > struct ima_rule_entry *entry; > int action = 0, actmask = flags | (flags << 1); > @@ -638,7 +648,7 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, > continue; > > if (!ima_match_rules(entry, inode, cred, secid, func, mask, > - keyring)) > + func_data)) > continue; > > action |= entry->flags & IMA_ACTION_FLAGS; > -- > 2.17.1 >