Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752369Ab1ECObe (ORCPT ); Tue, 3 May 2011 10:31:34 -0400 Received: from 236.121.91-79.rev.gaoland.net ([79.91.121.236]:46249 "EHLO mx.synack.fr" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751507Ab1ECOb3 (ORCPT ); Tue, 3 May 2011 10:31:29 -0400 From: Samir Bellabes To: linux-security-module@vger.kernel.org Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, jamal , Patrick McHardy , Evgeniy Polyakov , Grzegorz Nosek , Samir Bellabes Subject: [RFC v3 04/10] snet: introduce snet_event Date: Tue, 3 May 2011 16:24:17 +0200 Message-Id: <1304432663-1575-5-git-send-email-sam@synack.fr> X-Mailer: git-send-email 1.7.4.1 In-Reply-To: <1304432663-1575-1-git-send-email-sam@synack.fr> References: <1304432663-1575-1-git-send-email-sam@synack.fr> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6822 Lines: 260 This patch adds the snet's subsystem responsive of managing events snet is using the word 'event' for a couple of values [syscall, protocol]. For example, [listen, tcp] or [sendmsg, dccp] are events. This patch introduces a hastable 'event_hash' and operations (add/remove/search..) in order to manage which events have to be protected. With the help of the communication's subsystem, managing orders are coming from userspace. Signed-off-by: Samir Bellabes --- security/snet/snet_event.c | 201 ++++++++++++++++++++++++++++++++++++++++++++ security/snet/snet_event.h | 21 +++++ 2 files changed, 222 insertions(+), 0 deletions(-) create mode 100644 security/snet/snet_event.c create mode 100644 security/snet/snet_event.h diff --git a/security/snet/snet_event.c b/security/snet/snet_event.c new file mode 100644 index 0000000..7146d5a --- /dev/null +++ b/security/snet/snet_event.c @@ -0,0 +1,201 @@ +#include +#include +#include +#include +#include +#include +#include "snet_event.h" +#include "snet_netlink.h" +#include "snet_utils.h" + +static struct list_head *snet_evh; +static DEFINE_RWLOCK(snet_evh_lock); + +struct snet_event_entry { + struct list_head list; + struct snet_event se; +}; + +static struct kmem_cache *snet_event_entry_cachep; + +/* lookup for a snet_evh - before using this function, lock snet_evh_lock */ +static struct snet_event_entry *__snet_event_lookup(const enum snet_syscall syscall, + const u8 protocol) +{ + unsigned int h = 0; + struct list_head *l; + struct snet_event_entry *s; + + /* computing its hash value */ + h = jhash_2words(syscall, protocol, 0) % snet_evh_size; + l = &snet_evh[h]; + + list_for_each_entry(s, l, list) { + if ((s->se.protocol == protocol) && + (s->se.syscall == syscall)) { + return s; + } + } + return NULL; +} + +int snet_event_fill_info(struct sk_buff *skb, struct netlink_callback *cb) +{ + unsigned int i = 0, n = 0; + int ret = -1; + unsigned hashs_to_skip = cb->args[0]; + unsigned events_to_skip = cb->args[1]; + struct list_head *l; + struct snet_event_entry *s; + + read_lock_bh(&snet_evh_lock); + + for (i = 0; i < snet_evh_size; i++) { + if (i < hashs_to_skip) + continue; + l = &snet_evh[i]; + n = 0; + list_for_each_entry(s, l, list) { + if (++n < events_to_skip) + continue; + ret = snet_nl_list_fill_info(skb, + NETLINK_CB(cb->skb).pid, + cb->nlh->nlmsg_seq, + NLM_F_MULTI, + s->se.protocol, + s->se.syscall); + if (ret < 0) + goto errout; + } + } + +errout: + read_unlock_bh(&snet_evh_lock); + + cb->args[0] = i; + cb->args[1] = n; + return skb->len; +} + +/* + * check if a event is registered or not + * return 1 if event is registered, 0 if not + */ +int snet_event_is_registered(const enum snet_syscall syscall, const u8 protocol) +{ + int ret = 0; + + read_lock_bh(&snet_evh_lock); + if (__snet_event_lookup(syscall, protocol) != NULL) + ret = 1; + read_unlock_bh(&snet_evh_lock); + return ret; +} + +/* adding a event */ +int snet_event_insert(const enum snet_syscall syscall, const u8 protocol) +{ + struct snet_event_entry *data = NULL; + unsigned int h = 0; + int err = 0; + + data = kmem_cache_zalloc(snet_event_entry_cachep, GFP_KERNEL); + if (!data) { + err = -ENOMEM; + goto out; + } + + write_lock_bh(&snet_evh_lock); + /* check if event is already registered */ + if (__snet_event_lookup(syscall, protocol) != NULL) { + write_unlock_bh(&snet_evh_lock); + kmem_cache_free(snet_event_entry_cachep, data); + err = -EINVAL; + goto out; + } + + data->se.syscall = syscall; + data->se.protocol = protocol; + INIT_LIST_HEAD(&(data->list)); + h = jhash_2words(data->se.syscall, data->se.protocol, 0) % snet_evh_size; + list_add_tail(&data->list, &snet_evh[h]); + write_unlock_bh(&snet_evh_lock); + pr_debug("[%u]=(syscall=%s, protocol=%u)\n", + h, snet_syscall_name(syscall), protocol); +out: + return err; +} + +/* removing a event */ +int snet_event_remove(const enum snet_syscall syscall, const u8 protocol) +{ + struct snet_event_entry *data = NULL; + + write_lock_bh(&snet_evh_lock); + data = __snet_event_lookup(syscall, protocol); + if (data == NULL) { + write_unlock_bh(&snet_evh_lock); + return -EINVAL; + } + pr_debug("(syscall=%s, protocol=%u)\n", + snet_syscall_name(syscall), protocol); + list_del(&data->list); + write_unlock_bh(&snet_evh_lock); + kmem_cache_free(snet_event_entry_cachep, data); + return 0; +} + +/* flushing all events */ +void snet_event_flush(void) +{ + unsigned int i = 0; + + write_lock_bh(&snet_evh_lock); + for (i = 0; i < snet_evh_size; i++) { + struct snet_event_entry *data, *tmp; + list_for_each_entry_safe(data, tmp, &snet_evh[i], list) { + list_del(&data->list); + kmem_cache_free(snet_event_entry_cachep, data); + } + } + write_unlock_bh(&snet_evh_lock); + return; +} + +/* init function */ +int snet_event_init(void) +{ + int err = 0, i = 0; + + if (snet_evh_size == 0) { + printk(KERN_ERR "snet: bad snet_evh_size value\n"); + err = -EINVAL; + goto out; + } + + snet_evh = kzalloc(sizeof(struct list_head) * snet_evh_size, + GFP_KERNEL); + if (!snet_evh) { + printk(KERN_WARNING + "snet: can't alloc memory for snet_evh\n"); + err = -ENOMEM; + goto out; + } + + for (i = 0; i < snet_evh_size; i++) + INIT_LIST_HEAD(&snet_evh[i]); + + /* snet_event_entry_cachep is not destroyed */ + snet_event_entry_cachep = kmem_cache_create("snet_event_entry", + sizeof(struct snet_event_entry), + 0, SLAB_PANIC, NULL); +out: + return err; +} + +/* exit function */ +void snet_event_exit(void) +{ + kfree(snet_evh); + snet_evh = NULL; +} diff --git a/security/snet/snet_event.h b/security/snet/snet_event.h new file mode 100644 index 0000000..fa991c7 --- /dev/null +++ b/security/snet/snet_event.h @@ -0,0 +1,21 @@ +#ifndef _SNET_EVENT_H +#define _SNET_EVENT_H + +#include + +extern unsigned int snet_evh_size; + +/* manipulate the events hash table */ +int snet_event_fill_info(struct sk_buff *skb, struct netlink_callback *cb); +int snet_event_is_registered(const enum snet_syscall syscall, const u8 protocol); +int snet_event_insert(const enum snet_syscall syscall, const u8 protocol); +int snet_event_remove(const enum snet_syscall syscall, const u8 protocol); +void snet_event_flush(void); +void snet_event_dumpall(void); + +/* init function */ +int snet_event_init(void); +/* exit funtion */ +void snet_event_exit(void); + +#endif /* _SNET_EVENT_H */ -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/