From patchwork Tue Sep 14 16:33:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 12494217 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 E9F1AC4332F for ; Tue, 14 Sep 2021 16:36:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D838861164 for ; Tue, 14 Sep 2021 16:36:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229552AbhINQiL (ORCPT ); Tue, 14 Sep 2021 12:38:11 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]:3804 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229379AbhINQiK (ORCPT ); Tue, 14 Sep 2021 12:38:10 -0400 Received: from fraeml714-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4H887x2378z67Ljg; Wed, 15 Sep 2021 00:34:37 +0800 (CST) Received: from roberto-ThinkStation-P620.huawei.com (10.204.63.22) by fraeml714-chm.china.huawei.com (10.206.15.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.8; Tue, 14 Sep 2021 18:36:50 +0200 From: Roberto Sassu To: , , CC: , , , , , Roberto Sassu Subject: [PATCH v3 10/13] diglim: Interfaces - digest_query Date: Tue, 14 Sep 2021 18:33:58 +0200 Message-ID: <20210914163401.864635-11-roberto.sassu@huawei.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210914163401.864635-1-roberto.sassu@huawei.com> References: <20210914163401.864635-1-roberto.sassu@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.204.63.22] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To fraeml714-chm.china.huawei.com (10.206.15.33) X-CFilter-Loop: Reflected Precedence: bulk List-ID: Introduce the digest_query interface, which allows to write a query in the format - and to obtain all digest lists that include that digest. Signed-off-by: Roberto Sassu --- security/integrity/diglim/fs.c | 181 +++++++++++++++++++++++++++++++++ 1 file changed, 181 insertions(+) diff --git a/security/integrity/diglim/fs.c b/security/integrity/diglim/fs.c index deeb04f3c42c..e383254c72a4 100644 --- a/security/integrity/diglim/fs.c +++ b/security/integrity/diglim/fs.c @@ -44,6 +44,13 @@ static struct dentry *digest_lists_loaded_dir; * list (buffer) loaded through digest_list_add. */ static struct dentry *digest_list_label_dentry; +/** + * DOC: digest_query + * + * digest_query allows to write a query in the format - and + * to obtain all digest lists that include that digest. + */ +static struct dentry *digest_query_dentry; /** * DOC: digest_list_add * @@ -64,6 +71,7 @@ static struct dentry *digest_list_add_dentry; * described for digest_list_add. */ static struct dentry *digest_list_del_dentry; +char digest_query[CRYPTO_MAX_ALG_NAME + 1 + IMA_MAX_DIGEST_SIZE * 2 + 1]; char digest_list_label[NAME_MAX + 1]; static int parse_digest_list_filename(const char *digest_list_filename, @@ -264,6 +272,84 @@ static const struct file_operations digest_list_ascii_ops = { .release = seq_release, }; +/* + * *pos is the n-th reference to show among all the references in all digest + * items found with the query. + */ +static void *digest_query_start(struct seq_file *m, loff_t *pos) +{ + struct digest_item *d; + u8 digest[IMA_MAX_DIGEST_SIZE]; + enum hash_algo algo; + loff_t count = 0; + enum compact_types type = 0; + struct digest_list_item_ref *ref; + int ret; + + ret = parse_digest_list_filename(digest_query, digest, &algo); + if (ret < 0) + return NULL; + + for (type = 0; type < COMPACT__LAST; type++) { + d = __digest_lookup(digest, algo, type, NULL, NULL); + if (!d) + continue; + + list_for_each_entry(ref, &d->refs, list) { + if (count++ == *pos) { + m->private = d; + return ref; + } + } + } + + return NULL; +} + +static void *digest_query_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct digest_item *d = (struct digest_item *)m->private; + struct digest_list_item_ref *cur_ref = (struct digest_list_item_ref *)v; + struct digest_list_item_ref *ref; + + (*pos)++; + + list_for_each_entry(ref, &d->refs, list) { + if (ref != cur_ref) + continue; + + if (!list_is_last(&cur_ref->list, &d->refs)) + return list_next_entry(cur_ref, list); + } + + return NULL; +} + +static void digest_query_stop(struct seq_file *m, void *v) +{ +} + +static int digest_query_show(struct seq_file *m, void *v) +{ + struct digest_list_item_ref *ref = (struct digest_list_item_ref *)v; + struct digest_list_item *digest_list = ref->digest_list; + struct compact_list_hdr *hdr = get_hdr_ref(ref); + + if (!ref->digest_offset) { + seq_printf(m, "%s (actions: %d): type: %d, size: %lld\n", + digest_list->label, digest_list->actions, + COMPACT_DIGEST_LIST, digest_list->size); + return 0; + } + + seq_printf(m, + "%s (actions: %d): version: %d, algo: %s, type: %d, modifiers: %d, count: %d, datalen: %d\n", + digest_list->label, digest_list->actions, hdr->version, + hash_algo_name[hdr->algo], hdr->type, hdr->modifiers, + hdr->count, hdr->datalen); + return 0; +} + static int digest_list_get_secfs_files(char *label, u8 *digest, enum hash_algo algo, enum ops op, struct dentry **dentry, @@ -594,6 +680,94 @@ static const struct file_operations digest_list_label_ops = { .llseek = generic_file_llseek, }; +static const struct seq_operations digest_query_seqops = { + .start = digest_query_start, + .next = digest_query_next, + .stop = digest_query_stop, + .show = digest_query_show, +}; + +/* + * digest_query_open: sequentialize access to the add/del/query files + */ +static int digest_query_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(0, &flags)) + return -EBUSY; + + if (file->f_flags & O_WRONLY) + return 0; + + return seq_open(file, &digest_query_seqops); +} + +/* + * digest_query_write: write digest query (-). + */ +static ssize_t digest_query_write(struct file *file, const char __user *buf, + size_t datalen, loff_t *ppos) +{ + char *sep; + int rc, i; + + if (datalen >= sizeof(digest_query)) + return -EINVAL; + + rc = copy_from_user(digest_query, buf, datalen); + if (rc) + return -EFAULT; + + sep = strchr(digest_query, '-'); + if (!sep) { + rc = -EINVAL; + goto out; + } + + *sep = '\0'; + i = match_string(hash_algo_name, HASH_ALGO__LAST, digest_query); + if (i < 0) { + rc = -ENOENT; + goto out; + } + + *sep = '-'; + + for (i = 0; i < hash_digest_size[i] * 2; i++) { + if (!isxdigit(sep[i + 1])) { + rc = -EINVAL; + goto out; + } + } +out: + if (rc < 0) { + memset(digest_query, 0, sizeof(digest_query)); + return rc; + } + + return datalen; +} + +/* + * digest_query_release - release the query file + */ +static int digest_query_release(struct inode *inode, struct file *file) +{ + clear_bit(0, &flags); + + if (file->f_flags & O_WRONLY) + return 0; + + return seq_release(inode, file); +} + +static const struct file_operations digest_query_ops = { + .open = digest_query_open, + .write = digest_query_write, + .read = seq_read, + .release = digest_query_release, + .llseek = generic_file_llseek, +}; + static int __init diglim_fs_init(void) { diglim_dir = securityfs_create_dir("diglim", integrity_dir); @@ -623,8 +797,15 @@ static int __init diglim_fs_init(void) if (IS_ERR(digest_list_label_dentry)) goto out; + digest_query_dentry = securityfs_create_file("digest_query", 0600, + diglim_dir, NULL, + &digest_query_ops); + if (IS_ERR(digest_query_dentry)) + goto out; + return 0; out: + securityfs_remove(digest_query_dentry); securityfs_remove(digest_list_label_dentry); securityfs_remove(digest_list_del_dentry); securityfs_remove(digest_list_add_dentry);