From patchwork Wed Oct 23 23:39:48 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lakshmi Ramasubramanian X-Patchwork-Id: 11208039 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B8BC61920 for ; Wed, 23 Oct 2019 23:40:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96A552086D for ; Wed, 23 Oct 2019 23:40:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="YD86IyjK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2408045AbfJWXj6 (ORCPT ); Wed, 23 Oct 2019 19:39:58 -0400 Received: from linux.microsoft.com ([13.77.154.182]:51372 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392752AbfJWXj5 (ORCPT ); Wed, 23 Oct 2019 19:39:57 -0400 Received: from nramas-ThinkStation-P520.corp.microsoft.com (unknown [131.107.174.108]) by linux.microsoft.com (Postfix) with ESMTPSA id 36CA42010AC3; Wed, 23 Oct 2019 16:39:56 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 36CA42010AC3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1571873996; bh=TjZgExhOyS9lfgObayA5QjipEv197/miPQlmIXuI1sA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YD86IyjKkhcI2P1ZCoFpu3HtiH16eqctPx7rSgxp5L+9pPxQtOiKu2JCUk4j7lX8r +ySdN4SKkhxI7FX8RHT4MzbVHbmAl+HC7rltIXVFeaUS2AywG4DZ70864VbM/n2+3T dNDhG7EAoEJxHfh5hzgvHBpebuptE6TEhzbOADA0= From: Lakshmi Ramasubramanian To: zohar@linux.ibm.com, dhowells@redhat.com, casey@schaufler-ca.com, sashal@kernel.org, jamorris@linux.microsoft.com, linux-security-module@vger.kernel.org, linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org, keyrings@vger.kernel.org Cc: nramas@linux.microsoft.com Subject: [PATCH v2 2/4] KEYS: Queue key for measurement if ima is not initialized. Measure queued keys when ima is initialized Date: Wed, 23 Oct 2019 16:39:48 -0700 Message-Id: <20191023233950.22072-3-nramas@linux.microsoft.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191023233950.22072-1-nramas@linux.microsoft.com> References: <20191023233950.22072-1-nramas@linux.microsoft.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Defined functions to queue key for measurement if ima is not yet initialized. ima hook function ima_post_key_create_or_update will queue the key if ima is not yet initialized. Process queued keys and measure them when ima initialization is completed. Signed-off-by: Lakshmi Ramasubramanian --- security/integrity/ima/ima.h | 13 +++++ security/integrity/ima/ima_init.c | 9 ++- security/integrity/ima/ima_main.c | 4 +- security/integrity/ima/ima_queue.c | 94 ++++++++++++++++++++++++++++++ 4 files changed, 118 insertions(+), 2 deletions(-) diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index 2d4130ff5655..38279707632a 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -199,6 +199,17 @@ enum ima_hooks { __ima_hooks(__ima_hook_enumify) }; +/* + * To track trusted keys that need to be measured when IMA is initialized. + */ +struct ima_trusted_key_entry { + struct list_head list; + void *public_key; + u32 public_key_len; + char *key_description; + enum ima_hooks func; +}; + /* LIM API function definitions */ int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid, int mask, enum ima_hooks func, int *pcr, @@ -225,6 +236,8 @@ int ima_store_template(struct ima_template_entry *entry, int violation, const unsigned char *filename, int pcr); void ima_free_template_entry(struct ima_template_entry *entry); const char *ima_d_path(const struct path *path, char **pathbuf, char *filename); +int ima_queue_key_for_measurement(struct key *key, enum ima_hooks func); +void ima_measure_queued_keys(void); /* IMA policy related functions */ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid, diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c index 52847ce765a4..8734ed5322c7 100644 --- a/security/integrity/ima/ima_init.c +++ b/security/integrity/ima/ima_init.c @@ -132,5 +132,12 @@ int __init ima_init(void) ima_init_policy(); - return ima_fs_init(); + rc = ima_fs_init(); + if (rc != 0) + return rc; + + ima_initialized = true; + + ima_measure_queued_keys(); + return 0; } diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 8bde12385912..bce430b3386e 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -710,8 +710,10 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key, if (key->type != &key_type_asymmetric) return; - if (!ima_initialized) + if (!ima_initialized) { + ima_queue_key_for_measurement(key, NONE); return; + } pk = key->payload.data[asym_crypto]; process_buffer_measurement(pk->key, pk->keylen, diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c index 1ce8b1701566..d42987022c12 100644 --- a/security/integrity/ima/ima_queue.c +++ b/security/integrity/ima/ima_queue.c @@ -46,6 +46,13 @@ struct ima_h_table ima_htable = { */ static DEFINE_MUTEX(ima_extend_list_mutex); +/* + * Used to synchronize access to the list of trusted keys (ima_trusted_keys) + * that need to be measured when IMA is initialized. + */ +static DEFINE_MUTEX(ima_trusted_keys_mutex); +static LIST_HEAD(ima_trusted_keys); + /* lookup up the digest value in the hash table, and return the entry */ static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value, int pcr) @@ -232,3 +239,90 @@ int __init ima_init_digests(void) return 0; } + +static void ima_free_trusted_key_entry(struct ima_trusted_key_entry *entry) +{ + if (entry != NULL) { + if (entry->public_key != NULL) + kzfree(entry->public_key); + if (entry->key_description != NULL) + kzfree(entry->key_description); + kzfree(entry); + } +} + +static struct ima_trusted_key_entry *ima_alloc_trusted_queue_entry( + struct key *key, + enum ima_hooks func) +{ + int rc = 0; + const struct public_key *pk; + size_t key_description_len; + struct ima_trusted_key_entry *entry = NULL; + + pk = key->payload.data[asym_crypto]; + key_description_len = strlen(key->description) + 1; + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (entry != NULL) { + entry->public_key = kzalloc(pk->keylen, GFP_KERNEL); + entry->key_description = + kzalloc(key_description_len, GFP_KERNEL); + } + + if ((entry == NULL) || (entry->public_key == NULL) || + (entry->key_description == NULL)) { + rc = -ENOMEM; + goto out; + } + + strcpy(entry->key_description, key->description); + memcpy(entry->public_key, pk->key, pk->keylen); + entry->public_key_len = pk->keylen; + entry->func = func; + rc = 0; + +out: + if (rc) { + ima_free_trusted_key_entry(entry); + entry = NULL; + } + + return entry; +} + +int ima_queue_key_for_measurement(struct key *key, enum ima_hooks func) +{ + int rc = 0; + struct ima_trusted_key_entry *entry = NULL; + + mutex_lock(&ima_trusted_keys_mutex); + + entry = ima_alloc_trusted_queue_entry(key, func); + if (entry != NULL) { + INIT_LIST_HEAD(&entry->list); + list_add_tail(&entry->list, &ima_trusted_keys); + } else + rc = -ENOMEM; + + mutex_unlock(&ima_trusted_keys_mutex); + + return rc; +} + +void ima_measure_queued_keys(void) +{ + struct ima_trusted_key_entry *entry, *tmp; + + mutex_lock(&ima_trusted_keys_mutex); + + list_for_each_entry_safe(entry, tmp, &ima_trusted_keys, list) { + process_buffer_measurement(entry->public_key, + entry->public_key_len, + entry->key_description, + NONE, 0); + list_del(&entry->list); + ima_free_trusted_key_entry(entry); + } + + mutex_unlock(&ima_trusted_keys_mutex); +}