Right now only key objects, not crypto sessions, are limited. --- crypto/userspace/Makefile | 2 +- crypto/userspace/ncr-limits.c | 247 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 248 insertions(+), 1 deletions(-) create mode 100644 crypto/userspace/ncr-limits.c diff --git a/crypto/userspace/Makefile b/crypto/userspace/Makefile index a37969b..3dfbc39 100644 --- a/crypto/userspace/Makefile +++ b/crypto/userspace/Makefile @@ -1,6 +1,6 @@ ccflags-y += -I$(src)/libtommath -I$(src)/libtomcrypt/headers -I$(src) -DLTC_SOURCE -cryptodev-objs := cryptodev_main.o cryptodev_cipher.o utils.o +cryptodev-objs := cryptodev_main.o cryptodev_cipher.o ncr-limits.o utils.o obj-$(CONFIG_CRYPTO_USERSPACE) += cryptodev.o diff --git a/crypto/userspace/ncr-limits.c b/crypto/userspace/ncr-limits.c new file mode 100644 index 0000000..345cca7 --- /dev/null +++ b/crypto/userspace/ncr-limits.c @@ -0,0 +1,247 @@ +/* + * New driver for /dev/crypto device (aka CryptoDev) + + * Copyright (c) 2010 Katholieke Universiteit Leuven + * + * Author: Nikos Mavrogiannopoulos <nmav@xxxxxxxxxx> + * + * This file is part of linux cryptodev. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#include <linux/hash.h> +#include <linux/mutex.h> +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/ncr.h> +#include <linux/slab.h> +#include <linux/highmem.h> +#include <linux/random.h> +#include <asm/atomic.h> +#include <linux/version.h> +#include <linux/file.h> +#include <linux/cred.h> +#include "ncr-int.h" + +/* arbitrary now */ +static unsigned int max_per_user[] = { + [LIMIT_TYPE_KEY] = 128, +}; + +static unsigned int max_per_process[] = { + [LIMIT_TYPE_KEY] = 64, +}; + +struct limit_user_item_st { + struct hlist_node hlist; + uid_t uid; + atomic_t cnt[NUM_LIMIT_TYPES]; +}; + +struct limit_process_item_st { + struct hlist_node hlist; + pid_t pid; + atomic_t cnt[NUM_LIMIT_TYPES]; +}; + +static struct mutex user_limit_mutex; +#define USER_LIMIT_HASH_BITS 7 +#define USER_LIMIT_TABLE_SIZE (1 << USER_LIMIT_HASH_BITS) +static struct hlist_head user_limit_table[USER_LIMIT_TABLE_SIZE]; + +static struct hlist_head *user_limit_hash(uid_t uid) +{ + return &user_limit_table[hash_long(uid, USER_LIMIT_HASH_BITS)]; +} + +static struct mutex process_limit_mutex; +#define PROCESS_LIMIT_HASH_BITS 9 +#define PROCESS_LIMIT_TABLE_SIZE (1 << PROCESS_LIMIT_HASH_BITS) +static struct hlist_head process_limit_table[PROCESS_LIMIT_TABLE_SIZE]; + +static struct hlist_head *process_limit_hash(pid_t pid) +{ + return &process_limit_table[hash_long(pid, PROCESS_LIMIT_HASH_BITS)]; +} + +void ncr_limits_init(void) +{ + size_t i; + + mutex_init(&user_limit_mutex); + for (i = 0; i < USER_LIMIT_TABLE_SIZE; i++) + INIT_HLIST_HEAD(&user_limit_table[i]); + + mutex_init(&process_limit_mutex); + for (i = 0; i < PROCESS_LIMIT_TABLE_SIZE; i++) + INIT_HLIST_HEAD(&process_limit_table[i]); +} + +void ncr_limits_deinit(void) +{ +struct limit_process_item_st* pitem; +struct limit_user_item_st* uitem; +struct hlist_node *pos, *tmp; +size_t i; + + mutex_lock(&user_limit_mutex); + for (i = 0; i < USER_LIMIT_TABLE_SIZE; i++) { + hlist_for_each_entry_safe(uitem, pos, tmp, &user_limit_table[i], + hlist) { + hlist_del(&uitem->hlist); + kfree(uitem); + } + } + mutex_unlock(&user_limit_mutex); + + mutex_lock(&process_limit_mutex); + for (i = 0; i < PROCESS_LIMIT_TABLE_SIZE; i++) { + hlist_for_each_entry_safe(pitem, pos, tmp, + &process_limit_table[i], hlist) { + hlist_del(&pitem->hlist); + kfree(pitem); + } + } + mutex_unlock(&process_limit_mutex); + +} + +int ncr_limits_add_and_check(uid_t uid, pid_t pid, limits_type_t type) +{ +struct limit_process_item_st* pitem; +struct limit_user_item_st* uitem; +struct hlist_head *user_head, *process_head; +struct hlist_node *pos; +int add = 1; +int ret; + BUG_ON(type >= NUM_LIMIT_TYPES); + + user_head = user_limit_hash(uid); + mutex_lock(&user_limit_mutex); + hlist_for_each_entry(uitem, pos, user_head, hlist) { + if (uitem->uid == uid) { + add = 0; + + if (atomic_add_unless(&uitem->cnt[type], 1, max_per_user[type])==0) { + err(); + mutex_unlock(&user_limit_mutex); + return -EPERM; + } + break; + } + } + + if (add) { + size_t i; + + uitem = kmalloc( sizeof(*uitem), GFP_KERNEL); + if (uitem == NULL) { + err(); + mutex_unlock(&user_limit_mutex); + return -ENOMEM; + } + uitem->uid = uid; + for (i = 0; i < NUM_LIMIT_TYPES; i++) + atomic_set(&uitem->cnt[i], 0); + atomic_set(&uitem->cnt[type], 1); + + hlist_add_head(&uitem->hlist, user_head); + } + mutex_unlock(&user_limit_mutex); + + add = 1; + /* check process limits */ + process_head = process_limit_hash(uid); + mutex_lock(&process_limit_mutex); + hlist_for_each_entry(pitem, pos, process_head, hlist) { + if (pitem->pid == pid) { + add = 0; + if (atomic_add_unless(&pitem->cnt[type], 1, max_per_process[type])==0) { + err(); + mutex_unlock(&process_limit_mutex); + + ret = -EPERM; + goto restore_user; + } + break; + } + } + + + if (add) { + size_t i; + + pitem = kmalloc(sizeof(*pitem), GFP_KERNEL); + if (pitem == NULL) { + err(); + mutex_unlock(&process_limit_mutex); + ret = -ENOMEM; + goto restore_user; + } + pitem->pid = pid; + for (i = 0; i < NUM_LIMIT_TYPES; i++) + atomic_set(&pitem->cnt[i], 0); + atomic_set(&pitem->cnt[type], 1); + + hlist_add_head(&pitem->hlist, process_head); + } + mutex_unlock(&process_limit_mutex); + + return 0; + +restore_user: + mutex_lock(&user_limit_mutex); + hlist_for_each_entry(uitem, pos, user_head, hlist) { + if (uitem->uid == uid) { + atomic_dec(&uitem->cnt[type]); + break; + } + } + mutex_unlock(&user_limit_mutex); + return ret; +} + +void ncr_limits_remove(uid_t uid, pid_t pid, limits_type_t type) +{ +struct limit_process_item_st* pitem; +struct limit_user_item_st* uitem; +struct hlist_head *hhead; +struct hlist_node *pos; + + BUG_ON(type >= NUM_LIMIT_TYPES); + hhead = user_limit_hash(uid); + mutex_lock(&user_limit_mutex); + hlist_for_each_entry(uitem, pos, hhead, hlist) { + if (uitem->uid == uid) { + atomic_dec(&uitem->cnt[type]); + break; + } + } + mutex_unlock(&user_limit_mutex); + + /* check process limits */ + hhead = process_limit_hash(uid); + mutex_lock(&process_limit_mutex); + hlist_for_each_entry(pitem, pos, hhead, hlist) { + if (pitem->pid == pid) { + atomic_dec(&pitem->cnt[type]); + break; + } + } + mutex_unlock(&process_limit_mutex); + + return; +} -- 1.7.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html