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Diffstat (limited to 'kernel/audit.c')
-rw-r--r--kernel/audit.c205
1 files changed, 158 insertions, 47 deletions
diff --git a/kernel/audit.c b/kernel/audit.c
index df57b49..7dfac70 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -56,6 +56,7 @@
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/selinux.h>
+#include <linux/inotify.h>
#include "audit.h"
@@ -89,6 +90,7 @@ static int audit_backlog_wait_overflow = 0;
/* The identity of the user shutting down the audit system. */
uid_t audit_sig_uid = -1;
pid_t audit_sig_pid = -1;
+u32 audit_sig_sid = 0;
/* Records can be lost in several ways:
0) [suppressed in audit_alloc]
@@ -102,6 +104,12 @@ static atomic_t audit_lost = ATOMIC_INIT(0);
/* The netlink socket. */
static struct sock *audit_sock;
+/* Inotify handle. */
+struct inotify_handle *audit_ih;
+
+/* Hash for inode-based rules */
+struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
+
/* The audit_freelist is a list of pre-allocated audit buffers (if more
* than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
* being placed on the freelist). */
@@ -114,10 +122,8 @@ static struct task_struct *kauditd_task;
static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
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 */
-DEFINE_MUTEX(audit_netlink_mutex);
+/* Serialize requests from userspace. */
+static DEFINE_MUTEX(audit_cmd_mutex);
/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
* audit records. Since printk uses a 1024 byte buffer, this buffer
@@ -250,7 +256,7 @@ static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid)
"audit_rate_limit=%d old=%d by auid=%u",
limit, old, loginuid);
audit_rate_limit = limit;
- return old;
+ return 0;
}
static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
@@ -273,7 +279,7 @@ static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
"audit_backlog_limit=%d old=%d by auid=%u",
limit, old, loginuid);
audit_backlog_limit = limit;
- return old;
+ return 0;
}
static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
@@ -299,7 +305,7 @@ static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
"audit_enabled=%d old=%d by auid=%u",
state, old, loginuid);
audit_enabled = state;
- return old;
+ return 0;
}
static int audit_set_failure(int state, uid_t loginuid, u32 sid)
@@ -327,7 +333,7 @@ static int audit_set_failure(int state, uid_t loginuid, u32 sid)
"audit_failure=%d old=%d by auid=%u",
state, old, loginuid);
audit_failure = state;
- return old;
+ return 0;
}
static int kauditd_thread(void *dummy)
@@ -363,9 +369,52 @@ static int kauditd_thread(void *dummy)
remove_wait_queue(&kauditd_wait, &wait);
}
}
+}
+
+int audit_send_list(void *_dest)
+{
+ struct audit_netlink_list *dest = _dest;
+ int pid = dest->pid;
+ struct sk_buff *skb;
+
+ /* wait for parent to finish and send an ACK */
+ mutex_lock(&audit_cmd_mutex);
+ mutex_unlock(&audit_cmd_mutex);
+
+ while ((skb = __skb_dequeue(&dest->q)) != NULL)
+ netlink_unicast(audit_sock, skb, pid, 0);
+
+ kfree(dest);
+
return 0;
}
+struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
+ int multi, void *payload, int size)
+{
+ struct sk_buff *skb;
+ struct nlmsghdr *nlh;
+ int len = NLMSG_SPACE(size);
+ void *data;
+ int flags = multi ? NLM_F_MULTI : 0;
+ int t = done ? NLMSG_DONE : type;
+
+ skb = alloc_skb(len, GFP_KERNEL);
+ if (!skb)
+ return NULL;
+
+ nlh = NLMSG_PUT(skb, pid, seq, t, size);
+ nlh->nlmsg_flags = flags;
+ data = NLMSG_DATA(nlh);
+ memcpy(data, payload, size);
+ return skb;
+
+nlmsg_failure: /* Used by NLMSG_PUT */
+ if (skb)
+ kfree_skb(skb);
+ return NULL;
+}
+
/**
* audit_send_reply - send an audit reply message via netlink
* @pid: process id to send reply to
@@ -383,29 +432,13 @@ void audit_send_reply(int pid, int seq, int type, int done, int multi,
void *payload, int size)
{
struct sk_buff *skb;
- struct nlmsghdr *nlh;
- int len = NLMSG_SPACE(size);
- void *data;
- int flags = multi ? NLM_F_MULTI : 0;
- int t = done ? NLMSG_DONE : type;
-
- skb = alloc_skb(len, GFP_KERNEL);
+ skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
if (!skb)
return;
-
- nlh = NLMSG_PUT(skb, pid, seq, t, size);
- nlh->nlmsg_flags = flags;
- data = NLMSG_DATA(nlh);
- memcpy(data, payload, size);
-
/* Ignore failure. It'll only happen if the sender goes away,
because our timeout is set to infinite. */
netlink_unicast(audit_sock, skb, pid, 0);
return;
-
-nlmsg_failure: /* Used by NLMSG_PUT */
- if (skb)
- kfree_skb(skb);
}
/*
@@ -451,7 +484,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
struct audit_buffer *ab;
u16 msg_type = nlh->nlmsg_type;
uid_t loginuid; /* loginuid of sender */
- struct audit_sig_info sig_data;
+ struct audit_sig_info *sig_data;
+ char *ctx;
+ u32 len;
err = audit_netlink_ok(NETLINK_CB(skb).eff_cap, msg_type);
if (err)
@@ -503,12 +538,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
if (status_get->mask & AUDIT_STATUS_PID) {
int old = audit_pid;
if (sid) {
- char *ctx = NULL;
- u32 len;
- int rc;
- if ((rc = selinux_ctxid_to_string(
+ if ((err = selinux_ctxid_to_string(
sid, &ctx, &len)))
- return rc;
+ return err;
else
audit_log(NULL, GFP_KERNEL,
AUDIT_CONFIG_CHANGE,
@@ -523,10 +555,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
audit_pid = status_get->pid;
}
if (status_get->mask & AUDIT_STATUS_RATE_LIMIT)
- audit_set_rate_limit(status_get->rate_limit,
+ err = audit_set_rate_limit(status_get->rate_limit,
loginuid, sid);
if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
- audit_set_backlog_limit(status_get->backlog_limit,
+ err = audit_set_backlog_limit(status_get->backlog_limit,
loginuid, sid);
break;
case AUDIT_USER:
@@ -544,8 +576,6 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
"user pid=%d uid=%u auid=%u",
pid, uid, loginuid);
if (sid) {
- char *ctx = NULL;
- u32 len;
if (selinux_ctxid_to_string(
sid, &ctx, &len)) {
audit_log_format(ab,
@@ -584,10 +614,21 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
loginuid, sid);
break;
case AUDIT_SIGNAL_INFO:
- sig_data.uid = audit_sig_uid;
- sig_data.pid = audit_sig_pid;
+ err = selinux_ctxid_to_string(audit_sig_sid, &ctx, &len);
+ if (err)
+ return err;
+ sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
+ if (!sig_data) {
+ kfree(ctx);
+ return -ENOMEM;
+ }
+ sig_data->uid = audit_sig_uid;
+ sig_data->pid = audit_sig_pid;
+ memcpy(sig_data->ctx, ctx, len);
+ kfree(ctx);
audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
- 0, 0, &sig_data, sizeof(sig_data));
+ 0, 0, sig_data, sizeof(*sig_data) + len);
+ kfree(sig_data);
break;
default:
err = -EINVAL;
@@ -629,20 +670,30 @@ static void audit_receive(struct sock *sk, int length)
struct sk_buff *skb;
unsigned int qlen;
- mutex_lock(&audit_netlink_mutex);
+ mutex_lock(&audit_cmd_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);
}
- mutex_unlock(&audit_netlink_mutex);
+ mutex_unlock(&audit_cmd_mutex);
}
+#ifdef CONFIG_AUDITSYSCALL
+static const struct inotify_operations audit_inotify_ops = {
+ .handle_event = audit_handle_ievent,
+ .destroy_watch = audit_free_parent,
+};
+#endif
/* Initialize audit support at boot time. */
static int __init audit_init(void)
{
+#ifdef CONFIG_AUDITSYSCALL
+ int i;
+#endif
+
printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
audit_default ? "enabled" : "disabled");
audit_sock = netlink_kernel_create(NETLINK_AUDIT, 0, audit_receive,
@@ -661,6 +712,16 @@ static int __init audit_init(void)
selinux_audit_set_callback(&selinux_audit_rule_update);
audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
+
+#ifdef CONFIG_AUDITSYSCALL
+ audit_ih = inotify_init(&audit_inotify_ops);
+ if (IS_ERR(audit_ih))
+ audit_panic("cannot initialize inotify handle");
+
+ for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
+ INIT_LIST_HEAD(&audit_inode_hash[i]);
+#endif
+
return 0;
}
__initcall(audit_init);
@@ -690,10 +751,12 @@ static void audit_buffer_free(struct audit_buffer *ab)
kfree_skb(ab->skb);
spin_lock_irqsave(&audit_freelist_lock, flags);
- if (++audit_freelist_count > AUDIT_MAXFREE)
+ if (audit_freelist_count > AUDIT_MAXFREE)
kfree(ab);
- else
+ else {
+ audit_freelist_count++;
list_add(&ab->list, &audit_freelist);
+ }
spin_unlock_irqrestore(&audit_freelist_lock, flags);
}
@@ -988,28 +1051,76 @@ void audit_log_hex(struct audit_buffer *ab, const unsigned char *buf,
skb_put(skb, len << 1); /* new string is twice the old string */
}
+/*
+ * Format a string of no more than slen characters into the audit buffer,
+ * enclosed in quote marks.
+ */
+static void audit_log_n_string(struct audit_buffer *ab, size_t slen,
+ const char *string)
+{
+ int avail, new_len;
+ unsigned char *ptr;
+ struct sk_buff *skb;
+
+ BUG_ON(!ab->skb);
+ skb = ab->skb;
+ avail = skb_tailroom(skb);
+ new_len = slen + 3; /* enclosing quotes + null terminator */
+ if (new_len > avail) {
+ avail = audit_expand(ab, new_len);
+ if (!avail)
+ return;
+ }
+ ptr = skb->tail;
+ *ptr++ = '"';
+ memcpy(ptr, string, slen);
+ ptr += slen;
+ *ptr++ = '"';
+ *ptr = 0;
+ skb_put(skb, slen + 2); /* don't include null terminator */
+}
+
/**
- * audit_log_unstrustedstring - log a string that may contain random characters
+ * audit_log_n_unstrustedstring - log a string that may contain random characters
* @ab: audit_buffer
+ * @len: lenth of string (not including trailing null)
* @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).
+ *
+ * The caller specifies the number of characters in the string to log, which may
+ * or may not be the entire string.
*/
-void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
+const char *audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len,
+ const char *string)
{
const unsigned char *p = string;
while (*p) {
if (*p == '"' || *p < 0x21 || *p > 0x7f) {
- audit_log_hex(ab, string, strlen(string));
- return;
+ audit_log_hex(ab, string, len);
+ return string + len + 1;
}
p++;
}
- audit_log_format(ab, "\"%s\"", string);
+ audit_log_n_string(ab, len, string);
+ return p + 1;
+}
+
+/**
+ * audit_log_unstrustedstring - log a string that may contain random characters
+ * @ab: audit_buffer
+ * @string: string to be logged
+ *
+ * Same as audit_log_n_unstrustedstring(), except that strlen is used to
+ * determine string length.
+ */
+const char *audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
+{
+ return audit_log_n_untrustedstring(ab, strlen(string), string);
}
/* This is a helper-function to print the escaped d_path */