From patchwork Mon Jan 27 17:04:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 11352963 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 C00C8924 for ; Mon, 27 Jan 2020 17:07:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9EBFD20720 for ; Mon, 27 Jan 2020 17:07:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726571AbgA0RHQ (ORCPT ); Mon, 27 Jan 2020 12:07:16 -0500 Received: from lhrrgout.huawei.com ([185.176.76.210]:2307 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725828AbgA0RHQ (ORCPT ); Mon, 27 Jan 2020 12:07:16 -0500 Received: from LHREML710-CAH.china.huawei.com (unknown [172.18.7.107]) by Forcepoint Email with ESMTP id 9A8BFAB328A26817DD6D; Mon, 27 Jan 2020 17:07:14 +0000 (GMT) Received: from roberto-HP-EliteDesk-800-G2-DM-65W.huawei.com (10.204.65.160) by smtpsuk.huawei.com (10.201.108.33) with Microsoft SMTP Server (TLS) id 14.3.408.0; Mon, 27 Jan 2020 17:07:05 +0000 From: Roberto Sassu To: , , , CC: , , , Roberto Sassu Subject: [PATCH 7/8] ima: use ima_hash_algo for collision detection in the measurement list Date: Mon, 27 Jan 2020 18:04:42 +0100 Message-ID: <20200127170443.21538-8-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200127170443.21538-1-roberto.sassu@huawei.com> References: <20200127170443.21538-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.65.160] X-CFilter-Loop: Reflected Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Before calculating a digest for each PCR bank, collisions were detected with a SHA1 digest. This patch includes ima_hash_algo among the algorithms used to calculate the template digest and checks collisions on that digest. Signed-off-by: Roberto Sassu --- security/integrity/ima/ima.h | 1 + security/integrity/ima/ima_api.c | 2 +- security/integrity/ima/ima_crypto.c | 25 ++++++++++++++++++------- security/integrity/ima/ima_main.c | 1 + security/integrity/ima/ima_queue.c | 8 ++++---- security/integrity/ima/ima_template.c | 2 +- 6 files changed, 26 insertions(+), 13 deletions(-) diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index d959dab5bcce..3e1afa5150bc 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -51,6 +51,7 @@ extern int ima_policy_flag; /* set during initialization */ extern int ima_hash_algo; extern int ima_sha1_idx; +extern int ima_hash_algo_idx; extern int ima_appraise; extern struct tpm_chip *ima_tpm_chip; diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index ebaf0056735c..a9bb45de6db9 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -51,7 +51,7 @@ int ima_alloc_init_template(struct ima_event_data *event_data, if (!*entry) return -ENOMEM; - (*entry)->digests = kcalloc(ima_tpm_chip->nr_allocated_banks + 1, + (*entry)->digests = kcalloc(ima_tpm_chip->nr_allocated_banks + 2, sizeof(*(*entry)->digests), GFP_NOFS); if (!(*entry)->digests) { result = -ENOMEM; diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 786340feebbb..f84dfd8fc5ca 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -93,7 +93,7 @@ static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo) if (algo == ima_hash_algo) return tfm; - for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++) + for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 2; i++) if (ima_algo_array[i].algo == algo && ima_algo_array[i].tfm) return ima_algo_array[i].tfm; @@ -116,19 +116,20 @@ int __init ima_init_crypto(void) if (rc) return rc; - ima_algo_array = kmalloc_array(ima_tpm_chip->nr_allocated_banks + 1, + ima_algo_array = kmalloc_array(ima_tpm_chip->nr_allocated_banks + 2, sizeof(*ima_algo_array), GFP_KERNEL); if (!ima_algo_array) { rc = -ENOMEM; goto out; } - for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++) { + for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 2; i++) { ima_algo_array[i].tfm = NULL; ima_algo_array[i].algo = HASH_ALGO__LAST; } ima_sha1_idx = -1; + ima_hash_algo_idx = -1; for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++) { algo = ima_tpm_chip->allocated_banks[i].crypto_id; @@ -143,6 +144,7 @@ int __init ima_init_crypto(void) if (algo == ima_hash_algo) { ima_algo_array[i].tfm = ima_shash_tfm; + ima_hash_algo_idx = i; continue; } @@ -166,12 +168,21 @@ int __init ima_init_crypto(void) } ima_sha1_idx = i; - ima_algo_array[i].algo = HASH_ALGO_SHA1; + if (ima_hash_algo == HASH_ALGO_SHA1) + ima_hash_algo_idx = i; + + ima_algo_array[i++].algo = HASH_ALGO_SHA1; + } + + if (ima_hash_algo_idx < 0) { + ima_algo_array[i].tfm = ima_shash_tfm; + ima_algo_array[i].algo = ima_hash_algo; + ima_hash_algo_idx = i; } return 0; out_array: - for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++) { + for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 2; i++) { if (!ima_algo_array[i].tfm || ima_algo_array[i].tfm == ima_shash_tfm) continue; @@ -190,7 +201,7 @@ static void ima_free_tfm(struct crypto_shash *tfm) if (tfm == ima_shash_tfm) return; - for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++) + for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 2; i++) if (ima_algo_array[i].tfm == tfm) return; @@ -619,7 +630,7 @@ int ima_calc_field_array_hash(struct ima_field_data *field_data, entry->digests[ima_sha1_idx].alg_id = TPM_ALG_SHA1; - for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 1; i++) { + for (i = 0; i < ima_tpm_chip->nr_allocated_banks + 2; i++) { if (i == ima_sha1_idx) continue; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index c068067a0c47..6963d6c31bf1 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -31,6 +31,7 @@ #include "ima.h" int ima_sha1_idx; +int ima_hash_algo_idx; #ifdef CONFIG_IMA_APPRAISE int ima_appraise = IMA_APPRAISE_ENFORCE; diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c index 7f7509774b85..58983d0f0214 100644 --- a/security/integrity/ima/ima_queue.c +++ b/security/integrity/ima/ima_queue.c @@ -57,8 +57,8 @@ static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value, key = ima_hash_key(digest_value); rcu_read_lock(); hlist_for_each_entry_rcu(qe, &ima_htable.queue[key], hnext) { - rc = memcmp(qe->entry->digests[ima_sha1_idx].digest, - digest_value, TPM_DIGEST_SIZE); + rc = memcmp(qe->entry->digests[ima_hash_algo_idx].digest, + digest_value, hash_digest_size[ima_hash_algo]); if ((rc == 0) && (qe->entry->pcr == pcr)) { ret = qe; break; @@ -110,7 +110,7 @@ static int ima_add_digest_entry(struct ima_template_entry *entry, atomic_long_inc(&ima_htable.len); if (update_htable) { - key = ima_hash_key(entry->digests[ima_sha1_idx].digest); + key = ima_hash_key(entry->digests[ima_hash_algo_idx].digest); hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]); } @@ -162,7 +162,7 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation, const char *op, struct inode *inode, const unsigned char *filename) { - u8 *digest = entry->digests[ima_sha1_idx].digest; + u8 *digest = entry->digests[ima_hash_algo_idx].digest; struct tpm_digest *digests_arg = entry->digests; const char *audit_cause = "hash_added"; char tpm_audit_cause[AUDIT_CAUSE_LEN_MAX]; diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c index a9e1390c8e12..f71b5ee44179 100644 --- a/security/integrity/ima/ima_template.c +++ b/security/integrity/ima/ima_template.c @@ -311,7 +311,7 @@ static int ima_restore_template_data(struct ima_template_desc *template_desc, if (!*entry) return -ENOMEM; - (*entry)->digests = kcalloc(ima_tpm_chip->nr_allocated_banks + 1, + (*entry)->digests = kcalloc(ima_tpm_chip->nr_allocated_banks + 2, sizeof(*(*entry)->digests), GFP_NOFS); if (!(*entry)->digests) { kfree(*entry);