From patchwork Wed Mar 8 09:53:06 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Huizhao Wang X-Patchwork-Id: 13165537 X-Patchwork-Delegate: plautrba@redhat.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 930C2C678D5 for ; Wed, 8 Mar 2023 09:53:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230083AbjCHJxh (ORCPT ); Wed, 8 Mar 2023 04:53:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230142AbjCHJxU (ORCPT ); Wed, 8 Mar 2023 04:53:20 -0500 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC9B8559D2 for ; Wed, 8 Mar 2023 01:53:17 -0800 (PST) Received: from kwepemi500007.china.huawei.com (unknown [172.30.72.54]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4PWncM4Fynz16PK6; Wed, 8 Mar 2023 17:50:27 +0800 (CST) Received: from Linux-SUSE12SP5.huawei.com (10.67.136.158) by kwepemi500007.china.huawei.com (7.221.188.207) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Wed, 8 Mar 2023 17:53:15 +0800 From: wanghuizhao To: CC: , , , , , Subject: [PATCH v3 1/3] libselinux: migrating hashtab from policycoreutils Date: Wed, 8 Mar 2023 17:53:06 +0800 Message-ID: <20230308095308.60661-2-wanghuizhao1@huawei.com> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20230308095308.60661-1-wanghuizhao1@huawei.com> References: <20230308095308.60661-1-wanghuizhao1@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.67.136.158] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemi500007.china.huawei.com (7.221.188.207) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org To use hashtab in libselinux, migrate the existing hashtab template from policycoreutils/newrole to libselinux. Signed-off-by: wanghuizhao Acked-by: James Carter --- libselinux/src/hashtab.c | 208 +++++++++++++++++++++++++++++++++++++++++++++++ libselinux/src/hashtab.h | 115 ++++++++++++++++++++++++++ 2 files changed, 323 insertions(+) create mode 100644 libselinux/src/hashtab.c create mode 100644 libselinux/src/hashtab.h diff --git a/libselinux/src/hashtab.c b/libselinux/src/hashtab.c new file mode 100644 index 00000000..26d4f4c7 --- /dev/null +++ b/libselinux/src/hashtab.c @@ -0,0 +1,208 @@ + +/* Author : Stephen Smalley, */ + +/* FLASK */ + +/* + * Implementation of the hash table type. + */ + +#include +#include +#include "hashtab.h" + +hashtab_t hashtab_create(unsigned int (*hash_value) (hashtab_t h, + const_hashtab_key_t key), + int (*keycmp) (hashtab_t h, + const_hashtab_key_t key1, + const_hashtab_key_t key2), + unsigned int size) +{ + + hashtab_t p; + unsigned int i; + + p = (hashtab_t) malloc(sizeof(hashtab_val_t)); + if (p == NULL) + return p; + + memset(p, 0, sizeof(hashtab_val_t)); + p->size = size; + p->nel = 0; + p->hash_value = hash_value; + p->keycmp = keycmp; + p->htable = (hashtab_ptr_t *) malloc(sizeof(hashtab_ptr_t) * size); + if (p->htable == NULL) { + free(p); + return NULL; + } + for (i = 0; i < size; i++) + p->htable[i] = (hashtab_ptr_t) NULL; + + return p; +} + +int hashtab_insert(hashtab_t h, hashtab_key_t key, hashtab_datum_t datum) +{ + unsigned int hvalue; + hashtab_ptr_t prev, cur, newnode; + + if (!h) + return HASHTAB_OVERFLOW; + + hvalue = h->hash_value(h, key); + prev = NULL; + cur = h->htable[hvalue]; + while (cur && h->keycmp(h, key, cur->key) > 0) { + prev = cur; + cur = cur->next; + } + + if (cur && (h->keycmp(h, key, cur->key) == 0)) + return HASHTAB_PRESENT; + + newnode = (hashtab_ptr_t) malloc(sizeof(hashtab_node_t)); + if (newnode == NULL) + return HASHTAB_OVERFLOW; + memset(newnode, 0, sizeof(struct hashtab_node)); + newnode->key = key; + newnode->datum = datum; + if (prev) { + newnode->next = prev->next; + prev->next = newnode; + } else { + newnode->next = h->htable[hvalue]; + h->htable[hvalue] = newnode; + } + + h->nel++; + return HASHTAB_SUCCESS; +} + +int hashtab_remove(hashtab_t h, hashtab_key_t key, + void (*destroy) (hashtab_key_t k, + hashtab_datum_t d, void *args), void *args) +{ + unsigned int hvalue; + hashtab_ptr_t cur, last; + + if (!h) + return HASHTAB_MISSING; + + hvalue = h->hash_value(h, key); + last = NULL; + cur = h->htable[hvalue]; + while (cur != NULL && h->keycmp(h, key, cur->key) > 0) { + last = cur; + cur = cur->next; + } + + if (cur == NULL || (h->keycmp(h, key, cur->key) != 0)) + return HASHTAB_MISSING; + + if (last == NULL) + h->htable[hvalue] = cur->next; + else + last->next = cur->next; + + if (destroy) + destroy(cur->key, cur->datum, args); + free(cur); + h->nel--; + return HASHTAB_SUCCESS; +} + +hashtab_datum_t hashtab_search(hashtab_t h, const_hashtab_key_t key) +{ + + unsigned int hvalue; + hashtab_ptr_t cur; + + if (!h) + return NULL; + + hvalue = h->hash_value(h, key); + cur = h->htable[hvalue]; + while (cur != NULL && h->keycmp(h, key, cur->key) > 0) + cur = cur->next; + + if (cur == NULL || (h->keycmp(h, key, cur->key) != 0)) + return NULL; + + return cur->datum; +} + +void hashtab_destroy(hashtab_t h) +{ + unsigned int i; + hashtab_ptr_t cur, temp; + + if (!h) + return; + + for (i = 0; i < h->size; i++) { + cur = h->htable[i]; + while (cur != NULL) { + temp = cur; + cur = cur->next; + free(temp); + } + h->htable[i] = NULL; + } + + free(h->htable); + h->htable = NULL; + + free(h); +} + +int hashtab_map(hashtab_t h, + int (*apply) (hashtab_key_t k, + hashtab_datum_t d, void *args), void *args) +{ + unsigned int i; + hashtab_ptr_t cur; + int ret; + + if (!h) + return HASHTAB_SUCCESS; + + for (i = 0; i < h->size; i++) { + cur = h->htable[i]; + while (cur != NULL) { + ret = apply(cur->key, cur->datum, args); + if (ret) + return ret; + cur = cur->next; + } + } + return HASHTAB_SUCCESS; +} + +void hashtab_hash_eval(hashtab_t h, char *tag) +{ + unsigned int i; + int chain_len, slots_used, max_chain_len; + hashtab_ptr_t cur; + + slots_used = 0; + max_chain_len = 0; + for (i = 0; i < h->size; i++) { + cur = h->htable[i]; + if (cur) { + slots_used++; + chain_len = 0; + while (cur) { + chain_len++; + cur = cur->next; + } + + if (chain_len > max_chain_len) + max_chain_len = chain_len; + } + } + + printf + ("%s: %d entries and %d/%d buckets used, longest chain length %d\n", + tag, h->nel, slots_used, h->size, max_chain_len); +} diff --git a/libselinux/src/hashtab.h b/libselinux/src/hashtab.h new file mode 100644 index 00000000..78471269 --- /dev/null +++ b/libselinux/src/hashtab.h @@ -0,0 +1,115 @@ + +/* Author : Stephen Smalley, */ + +/* FLASK */ + +/* + * A hash table (hashtab) maintains associations between + * key values and datum values. The type of the key values + * and the type of the datum values is arbitrary. The + * functions for hash computation and key comparison are + * provided by the creator of the table. + */ + +#ifndef _NEWROLE_HASHTAB_H_ +#define _NEWROLE_HASHTAB_H_ + +#include +#include +#include + +typedef char *hashtab_key_t; /* generic key type */ +typedef const char *const_hashtab_key_t; /* constant generic key type */ +typedef void *hashtab_datum_t; /* generic datum type */ + +typedef struct hashtab_node *hashtab_ptr_t; + +typedef struct hashtab_node { + hashtab_key_t key; + hashtab_datum_t datum; + hashtab_ptr_t next; +} hashtab_node_t; + +typedef struct hashtab_val { + hashtab_ptr_t *htable; /* hash table */ + unsigned int size; /* number of slots in hash table */ + uint32_t nel; /* number of elements in hash table */ + unsigned int (*hash_value) (struct hashtab_val * h, const_hashtab_key_t key); /* hash function */ + int (*keycmp) (struct hashtab_val * h, const_hashtab_key_t key1, const_hashtab_key_t key2); /* key comparison function */ +} hashtab_val_t; + +typedef hashtab_val_t *hashtab_t; + +/* Define status codes for hash table functions */ +#define HASHTAB_SUCCESS 0 +#define HASHTAB_OVERFLOW -ENOMEM +#define HASHTAB_PRESENT -EEXIST +#define HASHTAB_MISSING -ENOENT + +/* + Creates a new hash table with the specified characteristics. + + Returns NULL if insufficient space is available or + the new hash table otherwise. + */ +extern hashtab_t hashtab_create(unsigned int (*hash_value) (hashtab_t h, + const_hashtab_key_t + key), + int (*keycmp) (hashtab_t h, + const_hashtab_key_t key1, + const_hashtab_key_t key2), + unsigned int size); +/* + Inserts the specified (key, datum) pair into the specified hash table. + + Returns HASHTAB_OVERFLOW if insufficient space is available or + HASHTAB_PRESENT if there is already an entry with the same key or + HASHTAB_SUCCESS otherwise. + */ +extern int hashtab_insert(hashtab_t h, hashtab_key_t k, hashtab_datum_t d); + +/* + Removes the entry with the specified key from the hash table. + Applies the specified destroy function to (key,datum,args) for + the entry. + + Returns HASHTAB_MISSING if no entry has the specified key or + HASHTAB_SUCCESS otherwise. + */ +extern int hashtab_remove(hashtab_t h, hashtab_key_t k, + void (*destroy) (hashtab_key_t k, + hashtab_datum_t d, + void *args), void *args); + +/* + Searches for the entry with the specified key in the hash table. + + Returns NULL if no entry has the specified key or + the datum of the entry otherwise. + */ +extern hashtab_datum_t hashtab_search(hashtab_t h, const_hashtab_key_t k); + +/* + Destroys the specified hash table. + */ +extern void hashtab_destroy(hashtab_t h); + +/* + Applies the specified apply function to (key,datum,args) + for each entry in the specified hash table. + + The order in which the function is applied to the entries + is dependent upon the internal structure of the hash table. + + If apply returns a non-zero status, then hashtab_map will cease + iterating through the hash table and will propagate the error + return to its caller. + */ +extern int hashtab_map(hashtab_t h, + int (*apply) (hashtab_key_t k, + hashtab_datum_t d, + void *args), void *args); + +extern void hashtab_hash_eval(hashtab_t h, char *tag); + +#endif