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authorLinus Torvalds <torvalds@g5.osdl.org>2006-03-25 09:24:53 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-03-25 09:24:53 -0800
commit1b9a3917366028cc451a98dd22e3bcd537d4e5c1 (patch)
treed911058720e0a9aeeaf9f407ccdc6fbf4047f47d /kernel
parent3661f00e2097676847deb01add1a0918044bd816 (diff)
parent71e1c784b24a026a490b3de01541fc5ee14ebc09 (diff)
Merge branch 'audit.b3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current: (22 commits) [PATCH] fix audit_init failure path [PATCH] EXPORT_SYMBOL patch for audit_log, audit_log_start, audit_log_end and audit_format [PATCH] sem2mutex: audit_netlink_sem [PATCH] simplify audit_free() locking [PATCH] Fix audit operators [PATCH] promiscuous mode [PATCH] Add tty to syscall audit records [PATCH] add/remove rule update [PATCH] audit string fields interface + consumer [PATCH] SE Linux audit events [PATCH] Minor cosmetic cleanups to the code moved into auditfilter.c [PATCH] Fix audit record filtering with !CONFIG_AUDITSYSCALL [PATCH] Fix IA64 success/failure indication in syscall auditing. [PATCH] Miscellaneous bug and warning fixes [PATCH] Capture selinux subject/object context information. [PATCH] Exclude messages by message type [PATCH] Collect more inode information during syscall processing. [PATCH] Pass dentry, not just name, in fsnotify creation hooks. [PATCH] Define new range of userspace messages. [PATCH] Filter rule comparators ... Fixed trivial conflict in security/selinux/hooks.c
Diffstat (limited to 'kernel')
-rw-r--r--kernel/Makefile2
-rw-r--r--kernel/audit.c175
-rw-r--r--kernel/audit.h88
-rw-r--r--kernel/auditfilter.c630
-rw-r--r--kernel/auditsc.c834
5 files changed, 1293 insertions, 436 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index aebd7a78984..ff1c11dc12c 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -26,7 +26,7 @@ obj-$(CONFIG_COMPAT) += compat.o
obj-$(CONFIG_CPUSETS) += cpuset.o
obj-$(CONFIG_IKCONFIG) += configs.o
obj-$(CONFIG_STOP_MACHINE) += stop_machine.o
-obj-$(CONFIG_AUDIT) += audit.o
+obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_SYSFS) += ksysfs.o
diff --git a/kernel/audit.c b/kernel/audit.c
index 0a813d2883e..04fe2e301b6 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -52,6 +52,7 @@
#include <linux/audit.h>
#include <net/sock.h>
+#include <net/netlink.h>
#include <linux/skbuff.h>
#include <linux/netlink.h>
@@ -72,7 +73,7 @@ static int audit_failure = AUDIT_FAIL_PRINTK;
* contains the (non-zero) pid. */
int audit_pid;
-/* If audit_limit is non-zero, limit the rate of sending audit records
+/* If audit_rate_limit is non-zero, limit the rate of sending audit records
* to that number per second. This prevents DoS attacks, but results in
* audit records being dropped. */
static int audit_rate_limit;
@@ -102,7 +103,7 @@ static struct sock *audit_sock;
* than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
* being placed on the freelist). */
static DEFINE_SPINLOCK(audit_freelist_lock);
-static int audit_freelist_count = 0;
+static int audit_freelist_count;
static LIST_HEAD(audit_freelist);
static struct sk_buff_head audit_skb_queue;
@@ -113,7 +114,7 @@ static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
/* The netlink socket is only to be read by 1 CPU, which lets us assume
* that list additions and deletions never happen simultaneously in
* auditsc.c */
-DECLARE_MUTEX(audit_netlink_sem);
+DEFINE_MUTEX(audit_netlink_mutex);
/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
* audit records. Since printk uses a 1024 byte buffer, this buffer
@@ -142,7 +143,7 @@ static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
nlh->nlmsg_pid = pid;
}
-static void audit_panic(const char *message)
+void audit_panic(const char *message)
{
switch (audit_failure)
{
@@ -186,8 +187,14 @@ static inline int audit_rate_check(void)
return retval;
}
-/* Emit at least 1 message per second, even if audit_rate_check is
- * throttling. */
+/**
+ * audit_log_lost - conditionally log lost audit message event
+ * @message: the message stating reason for lost audit message
+ *
+ * Emit at least 1 message per second, even if audit_rate_check is
+ * throttling.
+ * Always increment the lost messages counter.
+*/
void audit_log_lost(const char *message)
{
static unsigned long last_msg = 0;
@@ -218,7 +225,6 @@ void audit_log_lost(const char *message)
audit_backlog_limit);
audit_panic(message);
}
-
}
static int audit_set_rate_limit(int limit, uid_t loginuid)
@@ -300,8 +306,22 @@ static int kauditd_thread(void *dummy)
remove_wait_queue(&kauditd_wait, &wait);
}
}
+ return 0;
}
+/**
+ * audit_send_reply - send an audit reply message via netlink
+ * @pid: process id to send reply to
+ * @seq: sequence number
+ * @type: audit message type
+ * @done: done (last) flag
+ * @multi: multi-part message flag
+ * @payload: payload data
+ * @size: payload size
+ *
+ * Allocates an skb, builds the netlink message, and sends it to the pid.
+ * No failure notifications.
+ */
void audit_send_reply(int pid, int seq, int type, int done, int multi,
void *payload, int size)
{
@@ -342,15 +362,19 @@ static int audit_netlink_ok(kernel_cap_t eff_cap, u16 msg_type)
switch (msg_type) {
case AUDIT_GET:
case AUDIT_LIST:
+ case AUDIT_LIST_RULES:
case AUDIT_SET:
case AUDIT_ADD:
+ case AUDIT_ADD_RULE:
case AUDIT_DEL:
+ case AUDIT_DEL_RULE:
case AUDIT_SIGNAL_INFO:
if (!cap_raised(eff_cap, CAP_AUDIT_CONTROL))
err = -EPERM;
break;
case AUDIT_USER:
case AUDIT_FIRST_USER_MSG...AUDIT_LAST_USER_MSG:
+ case AUDIT_FIRST_USER_MSG2...AUDIT_LAST_USER_MSG2:
if (!cap_raised(eff_cap, CAP_AUDIT_WRITE))
err = -EPERM;
break;
@@ -376,7 +400,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
if (err)
return err;
- /* As soon as there's any sign of userspace auditd, start kauditd to talk to it */
+ /* As soon as there's any sign of userspace auditd,
+ * start kauditd to talk to it */
if (!kauditd_task)
kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
if (IS_ERR(kauditd_task)) {
@@ -430,6 +455,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
break;
case AUDIT_USER:
case AUDIT_FIRST_USER_MSG...AUDIT_LAST_USER_MSG:
+ case AUDIT_FIRST_USER_MSG2...AUDIT_LAST_USER_MSG2:
if (!audit_enabled && msg_type != AUDIT_USER_AVC)
return 0;
@@ -448,12 +474,23 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
break;
case AUDIT_ADD:
case AUDIT_DEL:
- if (nlh->nlmsg_len < sizeof(struct audit_rule))
+ if (nlmsg_len(nlh) < sizeof(struct audit_rule))
return -EINVAL;
/* fallthrough */
case AUDIT_LIST:
err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
- uid, seq, data, loginuid);
+ uid, seq, data, nlmsg_len(nlh),
+ loginuid);
+ break;
+ case AUDIT_ADD_RULE:
+ case AUDIT_DEL_RULE:
+ if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
+ return -EINVAL;
+ /* fallthrough */
+ case AUDIT_LIST_RULES:
+ err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
+ uid, seq, data, nlmsg_len(nlh),
+ loginuid);
break;
case AUDIT_SIGNAL_INFO:
sig_data.uid = audit_sig_uid;
@@ -469,9 +506,11 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
return err < 0 ? err : 0;
}
-/* Get message from skb (based on rtnetlink_rcv_skb). Each message is
+/*
+ * Get message from skb (based on rtnetlink_rcv_skb). Each message is
* processed by audit_receive_msg. Malformed skbs with wrong length are
- * discarded silently. */
+ * discarded silently.
+ */
static void audit_receive_skb(struct sk_buff *skb)
{
int err;
@@ -499,14 +538,14 @@ static void audit_receive(struct sock *sk, int length)
struct sk_buff *skb;
unsigned int qlen;
- down(&audit_netlink_sem);
+ mutex_lock(&audit_netlink_mutex);
for (qlen = skb_queue_len(&sk->sk_receive_queue); qlen; qlen--) {
skb = skb_dequeue(&sk->sk_receive_queue);
audit_receive_skb(skb);
kfree_skb(skb);
}
- up(&audit_netlink_sem);
+ mutex_unlock(&audit_netlink_mutex);
}
@@ -519,8 +558,9 @@ static int __init audit_init(void)
THIS_MODULE);
if (!audit_sock)
audit_panic("cannot initialize netlink socket");
+ else
+ audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
- audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
skb_queue_head_init(&audit_skb_queue);
audit_initialized = 1;
audit_enabled = audit_default;
@@ -600,7 +640,10 @@ err:
return NULL;
}
-/* Compute a serial number for the audit record. Audit records are
+/**
+ * audit_serial - compute a serial number for the audit record
+ *
+ * Compute a serial number for the audit record. Audit records are
* written to user-space as soon as they are generated, so a complete
* audit record may be written in several pieces. The timestamp of the
* record and this serial number are used by the user-space tools to
@@ -612,8 +655,8 @@ err:
* audit context (for those records that have a context), and emit them
* all at syscall exit. However, this could delay the reporting of
* significant errors until syscall exit (or never, if the system
- * halts). */
-
+ * halts).
+ */
unsigned int audit_serial(void)
{
static spinlock_t serial_lock = SPIN_LOCK_UNLOCKED;
@@ -649,6 +692,21 @@ static inline void audit_get_stamp(struct audit_context *ctx,
* will be written at syscall exit. If there is no associated task, tsk
* should be NULL. */
+/**
+ * audit_log_start - obtain an audit buffer
+ * @ctx: audit_context (may be NULL)
+ * @gfp_mask: type of allocation
+ * @type: audit message type
+ *
+ * Returns audit_buffer pointer on success or NULL on error.
+ *
+ * Obtain an audit buffer. This routine does locking to obtain the
+ * audit buffer, but then no locking is required for calls to
+ * audit_log_*format. If the task (ctx) is a task that is currently in a
+ * syscall, then the syscall is marked as auditable and an audit record
+ * will be written at syscall exit. If there is no associated task, then
+ * task context (ctx) should be NULL.
+ */
struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
int type)
{
@@ -661,6 +719,9 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
if (!audit_initialized)
return NULL;
+ if (unlikely(audit_filter_type(type)))
+ return NULL;
+
if (gfp_mask & __GFP_WAIT)
reserve = 0;
else
@@ -713,6 +774,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
/**
* audit_expand - expand skb in the audit buffer
* @ab: audit_buffer
+ * @extra: space to add at tail of the skb
*
* Returns 0 (no space) on failed expansion, or available space if
* successful.
@@ -729,10 +791,12 @@ static inline int audit_expand(struct audit_buffer *ab, int extra)
return skb_tailroom(skb);
}
-/* Format an audit message into the audit buffer. If there isn't enough
+/*
+ * Format an audit message into the audit buffer. If there isn't enough
* room in the audit buffer, more room will be allocated and vsnprint
* will be called a second time. Currently, we assume that a printk
- * can't format message larger than 1024 bytes, so we don't either. */
+ * can't format message larger than 1024 bytes, so we don't either.
+ */
static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
va_list args)
{
@@ -757,7 +821,8 @@ static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
/* The printk buffer is 1024 bytes long, so if we get
* here and AUDIT_BUFSIZ is at least 1024, then we can
* log everything that printk could have logged. */
- avail = audit_expand(ab, max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
+ avail = audit_expand(ab,
+ max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
if (!avail)
goto out;
len = vsnprintf(skb->tail, avail, fmt, args2);
@@ -768,8 +833,14 @@ out:
return;
}
-/* Format a message into the audit buffer. All the work is done in
- * audit_log_vformat. */
+/**
+ * audit_log_format - format a message into the audit buffer.
+ * @ab: audit_buffer
+ * @fmt: format string
+ * @...: optional parameters matching @fmt string
+ *
+ * All the work is done in audit_log_vformat.
+ */
void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
{
va_list args;
@@ -781,9 +852,18 @@ void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
va_end(args);
}
-/* This function will take the passed buf and convert it into a string of
- * ascii hex digits. The new string is placed onto the skb. */
-void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
+/**
+ * audit_log_hex - convert a buffer to hex and append it to the audit skb
+ * @ab: the audit_buffer
+ * @buf: buffer to convert to hex
+ * @len: length of @buf to be converted
+ *
+ * No return value; failure to expand is silently ignored.
+ *
+ * This function will take the passed buf and convert it into a string of
+ * ascii hex digits. The new string is placed onto the skb.
+ */
+void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
size_t len)
{
int i, avail, new_len;
@@ -812,10 +892,16 @@ void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
skb_put(skb, len << 1); /* new string is twice the old string */
}
-/* This code will escape a string that is passed to it if the string
- * contains a control character, unprintable character, double quote mark,
+/**
+ * audit_log_unstrustedstring - log a string that may contain random characters
+ * @ab: audit_buffer
+ * @string: string to be logged
+ *
+ * This code will escape a string that is passed to it if the string
+ * contains a control character, unprintable character, double quote mark,
* or a space. Unescaped strings will start and end with a double quote mark.
- * Strings that are escaped are printed in hex (2 digits per char). */
+ * Strings that are escaped are printed in hex (2 digits per char).
+ */
void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
{
const unsigned char *p = string;
@@ -854,10 +940,15 @@ void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
kfree(path);
}
-/* The netlink_* functions cannot be called inside an irq context, so
- * the audit buffer is places on a queue and a tasklet is scheduled to
+/**
+ * audit_log_end - end one audit record
+ * @ab: the audit_buffer
+ *
+ * The netlink_* functions cannot be called inside an irq context, so
+ * the audit buffer is placed on a queue and a tasklet is scheduled to
* remove them from the queue outside the irq context. May be called in
- * any context. */
+ * any context.
+ */
void audit_log_end(struct audit_buffer *ab)
{
if (!ab)
@@ -878,9 +969,18 @@ void audit_log_end(struct audit_buffer *ab)
audit_buffer_free(ab);
}
-/* Log an audit record. This is a convenience function that calls
- * audit_log_start, audit_log_vformat, and audit_log_end. It may be
- * called in any context. */
+/**
+ * audit_log - Log an audit record
+ * @ctx: audit context
+ * @gfp_mask: type of allocation
+ * @type: audit message type
+ * @fmt: format string to use
+ * @...: variable parameters matching the format string
+ *
+ * This is a convenience function that calls audit_log_start,
+ * audit_log_vformat, and audit_log_end. It may be called
+ * in any context.
+ */
void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
const char *fmt, ...)
{
@@ -895,3 +995,8 @@ void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
audit_log_end(ab);
}
}
+
+EXPORT_SYMBOL(audit_log_start);
+EXPORT_SYMBOL(audit_log_end);
+EXPORT_SYMBOL(audit_log_format);
+EXPORT_SYMBOL(audit_log);
diff --git a/kernel/audit.h b/kernel/audit.h
new file mode 100644
index 00000000000..bc5392076e2
--- /dev/null
+++ b/kernel/audit.h
@@ -0,0 +1,88 @@
+/* audit -- definition of audit_context structure and supporting types
+ *
+ * Copyright 2003-2004 Red Hat, Inc.
+ * Copyright 2005 Hewlett-Packard Development Company, L.P.
+ * Copyright 2005 IBM Corporation
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/mutex.h>
+#include <linux/fs.h>
+#include <linux/audit.h>
+
+/* 0 = no checking
+ 1 = put_count checking
+ 2 = verbose put_count checking
+*/
+#define AUDIT_DEBUG 0
+
+/* At task start time, the audit_state is set in the audit_context using
+ a per-task filter. At syscall entry, the audit_state is augmented by
+ the syscall filter. */
+enum audit_state {
+ AUDIT_DISABLED, /* Do not create per-task audit_context.
+ * No syscall-specific audit records can
+ * be generated. */
+ AUDIT_SETUP_CONTEXT, /* Create the per-task audit_context,
+ * but don't necessarily fill it in at
+ * syscall entry time (i.e., filter
+ * instead). */
+ AUDIT_BUILD_CONTEXT, /* Create the per-task audit_context,
+ * and always fill it in at syscall
+ * entry time. This makes a full
+ * syscall record available if some
+ * other part of the kernel decides it
+ * should be recorded. */
+ AUDIT_RECORD_CONTEXT /* Create the per-task audit_context,
+ * always fill it in at syscall entry
+ * time, and always write out the audit
+ * record at syscall exit time. */
+};
+
+/* Rule lists */
+struct audit_field {
+ u32 type;
+ u32 val;
+ u32 op;
+};
+
+struct audit_krule {
+ int vers_ops;
+ u32 flags;
+ u32 listnr;
+ u32 action;
+ u32 mask[AUDIT_BITMASK_SIZE];
+ u32 buflen; /* for data alloc on list rules */
+ u32 field_count;
+ struct audit_field *fields;
+};
+
+struct audit_entry {
+ struct list_head list;
+ struct rcu_head rcu;
+ struct audit_krule rule;
+};
+
+
+extern int audit_pid;
+extern int audit_comparator(const u32 left, const u32 op, const u32 right);
+
+extern void audit_send_reply(int pid, int seq, int type,
+ int done, int multi,
+ void *payload, int size);
+extern void audit_log_lost(const char *message);
+extern void audit_panic(const char *message);
+extern struct mutex audit_netlink_mutex;
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
new file mode 100644
index 00000000000..d3a8539f3a8
--- /dev/null
+++ b/kernel/auditfilter.c
@@ -0,0 +1,630 @@
+/* auditfilter.c -- filtering of audit events
+ *
+ * Copyright 2003-2004 Red Hat, Inc.
+ * Copyright 2005 Hewlett-Packard Development Company, L.P.
+ * Copyright 2005 IBM Corporation
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/audit.h>
+#include <linux/kthread.h>
+#include <linux/netlink.h>
+#include "audit.h"
+
+/* There are three lists of rules -- one to search at task creation
+ * time, one to search at syscall entry time, and another to search at
+ * syscall exit time. */
+struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
+ LIST_HEAD_INIT(audit_filter_list[0]),
+ LIST_HEAD_INIT(audit_filter_list[1]),
+ LIST_HEAD_INIT(audit_filter_list[2]),
+ LIST_HEAD_INIT(audit_filter_list[3]),
+ LIST_HEAD_INIT(audit_filter_list[4]),
+ LIST_HEAD_INIT(audit_filter_list[5]),
+#if AUDIT_NR_FILTERS != 6
+#error Fix audit_filter_list initialiser
+#endif
+};
+
+static inline void audit_free_rule(struct audit_entry *e)
+{
+ kfree(e->rule.fields);
+ kfree(e);
+}
+
+static inline void audit_free_rule_rcu(struct rcu_head *head)
+{
+ struct audit_entry *e = container_of(head, struct audit_entry, rcu);
+ audit_free_rule(e);
+}
+
+/* Unpack a filter field's string representation from user-space
+ * buffer. */
+static __attribute__((unused)) char *audit_unpack_string(void **bufp, size_t *remain, size_t len)
+{
+ char *str;
+
+ if (!*bufp || (len == 0) || (len > *remain))
+ return ERR_PTR(-EINVAL);
+
+ /* Of the currently implemented string fields, PATH_MAX
+ * defines the longest valid length.
+ */
+ if (len > PATH_MAX)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ str = kmalloc(len + 1, GFP_KERNEL);
+ if (unlikely(!str))
+ return ERR_PTR(-ENOMEM);
+
+ memcpy(str, *bufp, len);
+ str[len] = 0;
+ *bufp += len;
+ *remain -= len;
+
+ return str;
+}
+
+/* Common user-space to kernel rule translation. */
+static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule)
+{
+ unsigned listnr;
+ struct audit_entry *entry;
+ struct audit_field *fields;
+ int i, err;
+
+ err = -EINVAL;
+ listnr = rule->flags & ~AUDIT_FILTER_PREPEND;
+ switch(listnr) {
+ default:
+ goto exit_err;
+ case AUDIT_FILTER_USER:
+ case AUDIT_FILTER_TYPE:
+#ifdef CONFIG_AUDITSYSCALL
+ case AUDIT_FILTER_ENTRY:
+ case AUDIT_FILTER_EXIT:
+ case AUDIT_FILTER_TASK:
+#endif
+ ;
+ }
+ if (rule->action != AUDIT_NEVER && rule->action != AUDIT_POSSIBLE &&
+ rule->action != AUDIT_ALWAYS)
+ goto exit_err;
+ if (rule->field_count > AUDIT_MAX_FIELDS)
+ goto exit_err;
+
+ err = -ENOMEM;
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (unlikely(!entry))
+ goto exit_err;
+ fields = kmalloc(sizeof(*fields) * rule->field_count, GFP_KERNEL);
+ if (unlikely(!fields)) {
+ kfree(entry);
+ goto exit_err;
+ }
+
+ memset(&entry->rule, 0, sizeof(struct audit_krule));
+ memset(fields, 0, sizeof(struct audit_field));
+
+ entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND;
+ entry->rule.listnr = listnr;
+ entry->rule.action = rule->action;
+ entry->rule.field_count = rule->field_count;
+ entry->rule.fields = fields;
+
+ for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
+ entry->rule.mask[i] = rule->mask[i];
+
+ return entry;
+
+exit_err:
+ return ERR_PTR(err);
+}
+
+/* Translate struct audit_rule to kernel's rule respresentation.
+ * Exists for backward compatibility with userspace. */
+static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule)
+{
+ struct audit_entry *entry;
+ int err = 0;
+ int i;
+
+ entry = audit_to_entry_common(rule);
+ if (IS_ERR(entry))
+ goto exit_nofree;
+
+ for (i = 0; i < rule->field_count; i++) {
+ struct audit_field *f = &entry->rule.fields[i];
+
+ if (rule->fields[i] & AUDIT_UNUSED_BITS) {
+ err = -EINVAL;
+ goto exit_free;
+ }
+
+ f->op = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS);
+ f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS);
+ f->val = rule->values[i];
+
+ entry->rule.vers_ops = (f->op & AUDIT_OPERATORS) ? 2 : 1;
+
+ /* Support for legacy operators where
+ * AUDIT_NEGATE bit signifies != and otherwise assumes == */
+ if (f->op & AUDIT_NEGATE)
+ f->op = AUDIT_NOT_EQUAL;
+ else if (!f->op)
+ f->op = AUDIT_EQUAL;
+ else if (f->op == AUDIT_OPERATORS) {
+ err = -EINVAL;
+ goto exit_free;
+ }
+ }
+
+exit_nofree:
+ return entry;
+
+exit_free:
+ audit_free_rule(entry);
+ return ERR_PTR(err);
+}
+
+/* Translate struct audit_rule_data to kernel's rule respresentation. */
+static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data,
+ size_t datasz)
+{
+ int err = 0;
+ struct audit_entry *entry;
+ void *bufp;
+ /* size_t remain = datasz - sizeof(struct audit_rule_data); */
+ int i;
+
+ entry = audit_to_entry_common((struct audit_rule *)data);
+ if (IS_ERR(entry))
+ goto exit_nofree;
+
+ bufp = data->buf;
+ entry->rule.vers_ops = 2;
+ for (i = 0; i < data->field_count; i++) {
+ struct audit_field *f = &entry->rule.fields[i];
+
+ err = -EINVAL;
+ if (!(data->fieldflags[i] & AUDIT_OPERATORS) ||
+ data->fieldflags[i] & ~AUDIT_OPERATORS)
+ goto exit_free;
+
+ f->op = data->fieldflags[i] & AUDIT_OPERATORS;
+ f->type = data->fields[i];
+ switch(f->type) {
+ /* call type-specific conversion routines here */
+ default:
+ f->val = data->values[i];
+ }
+ }
+
+exit_nofree:
+ return entry;
+
+exit_free:
+ audit_free_rule(entry);
+ return ERR_PTR(err);
+}
+
+/* Pack a filter field's string representation into data block. */
+static inline size_t audit_pack_string(void **bufp, char *str)
+{
+ size_t len = strlen(str);
+
+ memcpy(*bufp, str, len);
+ *bufp += len;
+
+ return len;
+}
+
+/* Translate kernel rule respresentation to struct audit_rule.
+ * Exists for backward compatibility with userspace. */
+static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule)
+{
+ struct audit_rule *rule;
+ int i;
+
+ rule = kmalloc(sizeof(*rule), GFP_KERNEL);
+ if (unlikely(!rule))
+ return ERR_PTR(-ENOMEM);
+ memset(rule, 0, sizeof(*rule));
+
+ rule->flags = krule->flags | krule->listnr;
+ rule->action = krule->action;
+ rule->field_count = krule->field_count;
+ for (i = 0; i < rule->field_count; i++) {
+ rule->values[i] = krule->fields[i].val;
+ rule->fields[i] = krule->fields[i].type;
+
+ if (krule->vers_ops == 1) {
+ if (krule->fields[i].op & AUDIT_NOT_EQUAL)
+ rule->fields[i] |= AUDIT_NEGATE;
+ } else {
+ rule->fields[i] |= krule->fields[i].op;
+ }
+ }
+ for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i];
+
+ return rule;
+}
+
+/* Translate kernel rule respresentation to struct audit_rule_data. */
+static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule)
+{
+ struct audit_rule_data *data;
+ void *bufp;
+ int i;
+
+ data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL);
+ if (unlikely(!data))
+ return ERR_PTR(-ENOMEM);
+ memset(data, 0, sizeof(*data));
+
+ data->flags = krule->flags | krule->listnr;
+ data->action = krule->action;
+ data->field_count = krule->field_count;
+ bufp = data->buf;
+ for (i = 0; i < data->field_count; i++) {
+ struct audit_field *f = &krule->fields[i];
+
+ data->fields[i] = f->type;
+ data->fieldflags[i] = f->op;
+ switch(f->type) {
+ /* call type-specific conversion routines here */
+ default:
+ data->values[i] = f->val;
+ }
+ }
+ for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i];
+
+ return data;
+}
+
+/* Compare two rules in kernel format. Considered success if rules
+ * don't match. */
+static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b)
+{
+ int i;
+
+ if (a->flags != b->flags ||
+ a->listnr != b->listnr ||
+ a->action != b->action ||
+ a->field_count != b->field_count)
+ return 1;
+
+ for (i = 0; i < a->field_count; i++) {
+ if (a->fields[i].type != b->fields[i].type ||
+ a->fields[i].op != b->fields[i].op)
+ return 1;
+
+ switch(a->fields[i].type) {
+ /* call type-specific comparison routines here */
+ default:
+ if (a->fields[i].val != b->fields[i].val)
+ return 1;
+ }
+ }
+
+ for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
+ if (a->mask[i] != b->mask[i])
+ return 1;
+
+ return 0;
+}
+
+/* Add rule to given filterlist if not a duplicate. Protected by
+ * audit_netlink_mutex. */
+static inline int audit_add_rule(struct audit_entry *entry,
+ struct list_head *list)
+{
+ struct audit_entry *e;
+
+ /* Do not use the _rcu iterator here, since this is the only
+ * addition routine. */
+ list_for_each_entry(e, list, list) {
+ if (!audit_compare_rule(&entry->rule, &e->rule))
+ return -EEXIST;
+ }
+
+ if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
+ list_add_rcu(&entry->list, list);
+ } else {
+ list_add_tail_rcu(&entry->list, list);
+ }
+
+ return 0;
+}
+
+/* Remove an existing rule from filterlist. Protected by
+ * audit_netlink_mutex. */
+static inline int audit_del_rule(struct audit_entry *entry,
+ struct list_head *list)
+{
+ struct audit_entry *e;
+
+ /* Do not use the _rcu iterator here, since this is the only
+ * deletion routine. */
+ list_for_each_entry(e, list, list) {
+ if (!audit_compare_rule(&entry->rule, &e->rule)) {
+ list_del_rcu(&e->list);
+ call_rcu(&e->rcu, audit_free_rule_rcu);
+ return 0;
+ }
+ }
+ return -ENOENT; /* No matching rule */
+}
+
+/* List rules using struct audit_rule. Exists for backward
+ * compatibility with userspace. */
+static int audit_list(void *_dest)
+{
+ int pid, seq;
+ int *dest = _dest;
+ struct audit_entry *entry;
+ int i;
+
+ pid = dest[0];
+ seq = dest[1];
+ kfree(dest);
+
+ mutex_lock(&audit_netlink_mutex);
+
+ /* The *_rcu iterators not needed here because we are
+ always called with audit_netlink_mutex held. */
+ for (i=0; i<AUDIT_NR_FILTERS; i++) {
+ list_for_each_entry(entry, &audit_filter_list[i], list) {
+ struct audit_rule *rule;
+
+ rule = audit_krule_to_rule(&entry->rule);
+ if (unlikely(!rule))
+ break;
+ audit_send_reply(pid, seq, AUDIT_LIST, 0, 1,
+ rule, sizeof(*rule));
+ kfree(rule);
+ }
+ }
+ audit_send_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0);
+
+ mutex_unlock(&audit_netlink_mutex);
+ return 0;
+}
+
+/* List rules using struct audit_rule_data. */
+static int audit_list_rules(void *_dest)
+{
+ int pid, seq;
+ int *dest = _dest;
+ struct audit_entry *e;
+ int i;
+
+ pid = dest[0];
+ seq = dest[1];
+ kfree(dest);
+
+ mutex_lock(&audit_netlink_mutex);
+
+ /* The *_rcu iterators not needed here because we are
+ always called with audit_netlink_mutex held. */
+ for (i=0; i<AUDIT_NR_FILTERS; i++) {
+ list_for_each_entry(e, &audit_filter_list[i], list) {
+ struct audit_rule_data *data;
+
+ data = audit_krule_to_data(&e->rule);
+ if (unlikely(!data))
+ break;
+ audit_send_reply(pid, seq, AUDIT_LIST_RULES, 0, 1,
+ data, sizeof(*data));
+ kfree(data);
+ }
+ }
+ audit_send_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
+
+ mutex_unlock(&audit_netlink_mutex);
+ return 0;
+}
+
+/**
+ * audit_receive_filter - apply all rules to the specified message type
+ * @type: audit message type
+ * @pid: target pid for netlink audit messages
+ * @uid: target uid for netlink audit messages
+ * @seq: netlink audit message sequence (serial) number
+ * @data: payload data
+ * @datasz: size of payload data
+ * @loginuid: loginuid of sender
+ */
+int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
+ size_t datasz, uid_t loginuid)
+{
+ struct task_struct *tsk;
+ int *dest;
+ int err = 0;
+ struct audit_entry *entry;
+
+ switch (type) {
+ case AUDIT_LIST:
+ case AUDIT_LIST_RULES:
+ /* We can't just spew out the rules here because we might fill
+ * the available socket buffer space and deadlock waiting for
+ * auditctl to read from it... which isn't ever going to
+ * happen if we're actually running in the context of auditctl
+ * trying to _send_ the stuff */
+
+ dest = kmalloc(2 * sizeof(int), GFP_KERNEL);
+ if (!dest)
+ return -ENOMEM;
+ dest[0] = pid;
+ dest[1] = seq;
+
+ if (type == AUDIT_LIST)
+ tsk = kthread_run(audit_list, dest, "audit_list");
+ else
+ tsk = kthread_run(audit_list_rules, dest,
+ "audit_list_rules");
+ if (IS_ERR(tsk)) {
+ kfree(dest);
+ err = PTR_ERR(tsk);
+ }
+ break;
+ case AUDIT_ADD:
+ case AUDIT_ADD_RULE:
+ if (type == AUDIT_ADD)
+ entry = audit_rule_to_entry(data);
+ else
+ entry = audit_data_to_entry(data, datasz);
+ if (IS_ERR(entry))
+ return PTR_ERR(entry);
+
+ err = audit_add_rule(entry,
+ &audit_filter_list[entry->rule.listnr]);
+ audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
+ "auid=%u add rule to list=%d res=%d\n",
+ loginuid, entry->rule.listnr, !err);
+
+ if (err)
+ audit_free_rule(entry);
+ break;
+ case AUDIT_DEL:
+ case AUDIT_DEL_RULE:
+ if (type == AUDIT_DEL)
+ entry = audit_rule_to_entry(data);
+ else
+ entry = audit_data_to_entry(data, datasz);
+ if (IS_ERR(entry))
+ return PTR_ERR(entry);
+
+ err = audit_del_rule(entry,
+ &audit_filter_list[entry->rule.listnr]);
+ audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE,
+ "auid=%u remove rule from list=%d res=%d\n",
+ loginuid, entry->rule.listnr, !err);
+
+ audit_free_rule(entry);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return err;
+}
+
+int audit_comparator(const u32 left, const u32 op, const u32 right)
+{
+ switch (op) {
+ case AUDIT_EQUAL:
+ return (left == right);
+ case AUDIT_NOT_EQUAL:
+ return (left != right);
+ case AUDIT_LESS_THAN:
+ return (left < right);
+ case AUDIT_LESS_THAN_OR_EQUAL:
+ return (left <= right);
+ case AUDIT_GREATER_THAN:
+ return (left > right);
+ case AUDIT_GREATER_THAN_OR_EQUAL:
+ return (left >= right);
+ }
+ BUG();
+ return 0;
+}
+<