*
* Written by Rickard E. (Rik) Faith <faith@redhat.com>
*
- * Goals: 1) Integrate fully with SELinux.
+ * Goals: 1) Integrate fully with Security Modules.
* 2) Minimal run-time overhead:
* a) Minimal when syscall auditing is disabled (audit_enable=0).
* b) Small when syscall auditing is enabled and no audit record
#include <linux/init.h>
#include <asm/types.h>
-#include <asm/atomic.h>
+#include <linux/atomic.h>
#include <linux/mm.h>
#include <linux/module.h>
+#include <linux/slab.h>
#include <linux/err.h>
#include <linux/kthread.h>
#include <net/sock.h>
#include <net/netlink.h>
#include <linux/skbuff.h>
+#ifdef CONFIG_SECURITY
+#include <linux/security.h>
+#endif
#include <linux/netlink.h>
-#include <linux/selinux.h>
-#include <linux/inotify.h>
#include <linux/freezer.h>
#include <linux/tty.h>
#include "audit.h"
-/* No auditing will take place until audit_initialized != 0.
+/* No auditing will take place until audit_initialized == AUDIT_INITIALIZED.
* (Initialization happens after skb_init is called.) */
+#define AUDIT_DISABLED -1
+#define AUDIT_UNINITIALIZED 0
+#define AUDIT_INITIALIZED 1
static int audit_initialized;
#define AUDIT_OFF 0
int audit_enabled;
int audit_ever_enabled;
+EXPORT_SYMBOL_GPL(audit_enabled);
+
/* Default state when kernel boots without any parameters. */
static int audit_default;
/* If auditing cannot proceed, audit_failure selects what happens. */
static int audit_failure = AUDIT_FAIL_PRINTK;
-/* If audit records are to be written to the netlink socket, audit_pid
- * contains the (non-zero) pid. */
+/*
+ * If audit records are to be written to the netlink socket, audit_pid
+ * contains the pid of the auditd process and audit_nlk_pid contains
+ * the pid to use to send netlink messages to that process.
+ */
int audit_pid;
+static int audit_nlk_pid;
/* 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
/* 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];
static LIST_HEAD(audit_freelist);
static struct sk_buff_head audit_skb_queue;
+/* queue of skbs to send to auditd when/if it comes back */
+static struct sk_buff_head audit_skb_hold_queue;
static struct task_struct *kauditd_task;
static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
/* Serialize requests from userspace. */
-static DEFINE_MUTEX(audit_cmd_mutex);
+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
gfp_t gfp_mask;
};
+struct audit_reply {
+ int pid;
+ struct sk_buff *skb;
+};
+
static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
{
if (ab) {
printk(KERN_ERR "audit: %s\n", message);
break;
case AUDIT_FAIL_PANIC:
- panic("audit: %s\n", message);
+ /* test audit_pid since printk is always losey, why bother? */
+ if (audit_pid)
+ panic("audit: %s\n", message);
break;
}
}
}
static int audit_log_config_change(char *function_name, int new, int old,
- uid_t loginuid, u32 sid, int allow_changes)
+ uid_t loginuid, u32 sessionid, u32 sid,
+ int allow_changes)
{
struct audit_buffer *ab;
int rc = 0;
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
- audit_log_format(ab, "%s=%d old=%d by auid=%u", function_name, new,
- old, loginuid);
+ audit_log_format(ab, "%s=%d old=%d auid=%u ses=%u", function_name, new,
+ old, loginuid, sessionid);
if (sid) {
char *ctx = NULL;
u32 len;
- rc = selinux_sid_to_string(sid, &ctx, &len);
+ rc = security_secid_to_secctx(sid, &ctx, &len);
if (rc) {
audit_log_format(ab, " sid=%u", sid);
allow_changes = 0; /* Something weird, deny request */
} else {
audit_log_format(ab, " subj=%s", ctx);
- kfree(ctx);
+ security_release_secctx(ctx, len);
}
}
audit_log_format(ab, " res=%d", allow_changes);
}
static int audit_do_config_change(char *function_name, int *to_change,
- int new, uid_t loginuid, u32 sid)
+ int new, uid_t loginuid, u32 sessionid,
+ u32 sid)
{
int allow_changes, rc = 0, old = *to_change;
allow_changes = 1;
if (audit_enabled != AUDIT_OFF) {
- rc = audit_log_config_change(function_name, new, old,
- loginuid, sid, allow_changes);
+ rc = audit_log_config_change(function_name, new, old, loginuid,
+ sessionid, sid, allow_changes);
if (rc)
allow_changes = 0;
}
return rc;
}
-static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid)
+static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sessionid,
+ u32 sid)
{
return audit_do_config_change("audit_rate_limit", &audit_rate_limit,
- limit, loginuid, sid);
+ limit, loginuid, sessionid, sid);
}
-static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
+static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sessionid,
+ u32 sid)
{
return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit,
- limit, loginuid, sid);
+ limit, loginuid, sessionid, sid);
}
-static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
+static int audit_set_enabled(int state, uid_t loginuid, u32 sessionid, u32 sid)
{
int rc;
if (state < AUDIT_OFF || state > AUDIT_LOCKED)
return -EINVAL;
rc = audit_do_config_change("audit_enabled", &audit_enabled, state,
- loginuid, sid);
+ loginuid, sessionid, sid);
if (!rc)
audit_ever_enabled |= !!state;
return rc;
}
-static int audit_set_failure(int state, uid_t loginuid, u32 sid)
+static int audit_set_failure(int state, uid_t loginuid, u32 sessionid, u32 sid)
{
if (state != AUDIT_FAIL_SILENT
&& state != AUDIT_FAIL_PRINTK
return -EINVAL;
return audit_do_config_change("audit_failure", &audit_failure, state,
- loginuid, sid);
+ loginuid, sessionid, sid);
+}
+
+/*
+ * Queue skbs to be sent to auditd when/if it comes back. These skbs should
+ * already have been sent via prink/syslog and so if these messages are dropped
+ * it is not a huge concern since we already passed the audit_log_lost()
+ * notification and stuff. This is just nice to get audit messages during
+ * boot before auditd is running or messages generated while auditd is stopped.
+ * This only holds messages is audit_default is set, aka booting with audit=1
+ * or building your kernel that way.
+ */
+static void audit_hold_skb(struct sk_buff *skb)
+{
+ if (audit_default &&
+ skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)
+ skb_queue_tail(&audit_skb_hold_queue, skb);
+ else
+ kfree_skb(skb);
+}
+
+/*
+ * For one reason or another this nlh isn't getting delivered to the userspace
+ * audit daemon, just send it to printk.
+ */
+static void audit_printk_skb(struct sk_buff *skb)
+{
+ struct nlmsghdr *nlh = nlmsg_hdr(skb);
+ char *data = NLMSG_DATA(nlh);
+
+ if (nlh->nlmsg_type != AUDIT_EOE) {
+ if (printk_ratelimit())
+ printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data);
+ else
+ audit_log_lost("printk limit exceeded\n");
+ }
+
+ audit_hold_skb(skb);
+}
+
+static void kauditd_send_skb(struct sk_buff *skb)
+{
+ int err;
+ /* take a reference in case we can't send it and we want to hold it */
+ skb_get(skb);
+ err = netlink_unicast(audit_sock, skb, audit_nlk_pid, 0);
+ if (err < 0) {
+ BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
+ printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
+ audit_log_lost("auditd disappeared\n");
+ audit_pid = 0;
+ /* we might get lucky and get this in the next auditd */
+ audit_hold_skb(skb);
+ } else
+ /* drop the extra reference if sent ok */
+ consume_skb(skb);
}
static int kauditd_thread(void *dummy)
set_freezable();
while (!kthread_should_stop()) {
+ /*
+ * if auditd just started drain the queue of messages already
+ * sent to syslog/printk. remember loss here is ok. we already
+ * called audit_log_lost() if it didn't go out normally. so the
+ * race between the skb_dequeue and the next check for audit_pid
+ * doesn't matter.
+ *
+ * if you ever find kauditd to be too slow we can get a perf win
+ * by doing our own locking and keeping better track if there
+ * are messages in this queue. I don't see the need now, but
+ * in 5 years when I want to play with this again I'll see this
+ * note and still have no friggin idea what i'm thinking today.
+ */
+ if (audit_default && audit_pid) {
+ skb = skb_dequeue(&audit_skb_hold_queue);
+ if (unlikely(skb)) {
+ while (skb && audit_pid) {
+ kauditd_send_skb(skb);
+ skb = skb_dequeue(&audit_skb_hold_queue);
+ }
+ }
+ }
+
skb = skb_dequeue(&audit_skb_queue);
wake_up(&audit_backlog_wait);
if (skb) {
- if (audit_pid) {
- int err = netlink_unicast(audit_sock, skb, audit_pid, 0);
- if (err < 0) {
- BUG_ON(err != -ECONNREFUSED); /* Shoudn't happen */
- printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
- audit_pid = 0;
- }
- } else {
- if (printk_ratelimit())
- printk(KERN_NOTICE "%s\n", skb->data +
- NLMSG_SPACE(0));
- else
- audit_log_lost("printk limit exceeded\n");
- kfree_skb(skb);
- }
+ if (audit_pid)
+ kauditd_send_skb(skb);
+ else
+ audit_printk_skb(skb);
} else {
DECLARE_WAITQUEUE(wait, current);
set_current_state(TASK_INTERRUPTIBLE);
return 0;
}
-static int audit_prepare_user_tty(pid_t pid, uid_t loginuid)
+static int audit_prepare_user_tty(pid_t pid, uid_t loginuid, u32 sessionid)
{
struct task_struct *tsk;
int err;
- read_lock(&tasklist_lock);
- tsk = find_task_by_pid(pid);
- err = -ESRCH;
- if (!tsk)
- goto out;
- err = 0;
-
- spin_lock_irq(&tsk->sighand->siglock);
- if (!tsk->signal->audit_tty)
- err = -EPERM;
- spin_unlock_irq(&tsk->sighand->siglock);
- if (err)
- goto out;
-
- tty_audit_push_task(tsk, loginuid);
-out:
- read_unlock(&tasklist_lock);
+ rcu_read_lock();
+ tsk = find_task_by_vpid(pid);
+ if (!tsk) {
+ rcu_read_unlock();
+ return -ESRCH;
+ }
+ get_task_struct(tsk);
+ rcu_read_unlock();
+ err = tty_audit_push_task(tsk, loginuid, sessionid);
+ put_task_struct(tsk);
return err;
}
return 0;
}
-#ifdef CONFIG_AUDIT_TREE
-static int prune_tree_thread(void *unused)
-{
- mutex_lock(&audit_cmd_mutex);
- audit_prune_trees();
- mutex_unlock(&audit_cmd_mutex);
- return 0;
-}
-
-void audit_schedule_prune(void)
-{
- kthread_run(prune_tree_thread, NULL, "audit_prune_tree");
-}
-#endif
-
struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
- int multi, void *payload, int size)
+ int multi, const 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 = nlmsg_new(size, GFP_KERNEL);
if (!skb)
return NULL;
- nlh = NLMSG_PUT(skb, pid, seq, t, size);
- nlh->nlmsg_flags = flags;
- data = NLMSG_DATA(nlh);
+ nlh = NLMSG_NEW(skb, pid, seq, t, size, flags);
+ data = NLMSG_DATA(nlh);
memcpy(data, payload, size);
return skb;
-nlmsg_failure: /* Used by NLMSG_PUT */
+nlmsg_failure: /* Used by NLMSG_NEW */
if (skb)
kfree_skb(skb);
return NULL;
}
+static int audit_send_reply_thread(void *arg)
+{
+ struct audit_reply *reply = (struct audit_reply *)arg;
+
+ mutex_lock(&audit_cmd_mutex);
+ mutex_unlock(&audit_cmd_mutex);
+
+ /* Ignore failure. It'll only happen if the sender goes away,
+ because our timeout is set to infinite. */
+ netlink_unicast(audit_sock, reply->skb, reply->pid, 0);
+ kfree(reply);
+ return 0;
+}
/**
* audit_send_reply - send an audit reply message via netlink
* @pid: process id to send reply to
* 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)
+static void audit_send_reply(int pid, int seq, int type, int done, int multi,
+ const void *payload, int size)
{
- struct sk_buff *skb;
+ struct sk_buff *skb;
+ struct task_struct *tsk;
+ struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
+ GFP_KERNEL);
+
+ if (!reply)
+ return;
+
skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
if (!skb)
+ goto out;
+
+ reply->pid = pid;
+ reply->skb = skb;
+
+ tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
+ if (!IS_ERR(tsk))
return;
- /* 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;
+ kfree_skb(skb);
+out:
+ kfree(reply);
}
/*
}
static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
- u32 pid, u32 uid, uid_t auid, u32 sid)
+ u32 pid, u32 uid, uid_t auid, u32 ses,
+ u32 sid)
{
int rc = 0;
char *ctx = NULL;
}
*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
- audit_log_format(*ab, "user pid=%d uid=%u auid=%u",
- pid, uid, auid);
+ audit_log_format(*ab, "user pid=%d uid=%u auid=%u ses=%u",
+ pid, uid, auid, ses);
if (sid) {
- rc = selinux_sid_to_string(sid, &ctx, &len);
+ rc = security_secid_to_secctx(sid, &ctx, &len);
if (rc)
audit_log_format(*ab, " ssid=%u", sid);
- else
+ else {
audit_log_format(*ab, " subj=%s", ctx);
- kfree(ctx);
+ security_release_secctx(ctx, len);
+ }
}
return rc;
struct audit_buffer *ab;
u16 msg_type = nlh->nlmsg_type;
uid_t loginuid; /* loginuid of sender */
+ u32 sessionid;
struct audit_sig_info *sig_data;
char *ctx = NULL;
u32 len;
pid = NETLINK_CREDS(skb)->pid;
uid = NETLINK_CREDS(skb)->uid;
- loginuid = NETLINK_CB(skb).loginuid;
- sid = NETLINK_CB(skb).sid;
+ loginuid = audit_get_loginuid(current);
+ sessionid = audit_get_sessionid(current);
+ security_task_getsecid(current, &sid);
seq = nlh->nlmsg_seq;
data = NLMSG_DATA(nlh);
status_get = (struct audit_status *)data;
if (status_get->mask & AUDIT_STATUS_ENABLED) {
err = audit_set_enabled(status_get->enabled,
- loginuid, sid);
- if (err < 0) return err;
+ loginuid, sessionid, sid);
+ if (err < 0)
+ return err;
}
if (status_get->mask & AUDIT_STATUS_FAILURE) {
err = audit_set_failure(status_get->failure,
- loginuid, sid);
- if (err < 0) return err;
+ loginuid, sessionid, sid);
+ if (err < 0)
+ return err;
}
if (status_get->mask & AUDIT_STATUS_PID) {
int new_pid = status_get->pid;
if (audit_enabled != AUDIT_OFF)
audit_log_config_change("audit_pid", new_pid,
audit_pid, loginuid,
- sid, 1);
+ sessionid, sid, 1);
audit_pid = new_pid;
+ audit_nlk_pid = NETLINK_CB(skb).pid;
}
- if (status_get->mask & AUDIT_STATUS_RATE_LIMIT)
+ if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) {
err = audit_set_rate_limit(status_get->rate_limit,
- loginuid, sid);
+ loginuid, sessionid, sid);
+ if (err < 0)
+ return err;
+ }
if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
err = audit_set_backlog_limit(status_get->backlog_limit,
- loginuid, sid);
+ loginuid, sessionid, sid);
break;
case AUDIT_USER:
case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
if (!audit_enabled && msg_type != AUDIT_USER_AVC)
return 0;
- err = audit_filter_user(&NETLINK_CB(skb), msg_type);
+ err = audit_filter_user(&NETLINK_CB(skb));
if (err == 1) {
err = 0;
if (msg_type == AUDIT_USER_TTY) {
- err = audit_prepare_user_tty(pid, loginuid);
+ err = audit_prepare_user_tty(pid, loginuid,
+ sessionid);
if (err)
break;
}
audit_log_common_recv_msg(&ab, msg_type, pid, uid,
- loginuid, sid);
+ loginuid, sessionid, sid);
if (msg_type != AUDIT_USER_TTY)
audit_log_format(ab, " msg='%.1024s'",
audit_log_format(ab, " msg=");
size = nlmsg_len(nlh);
- audit_log_n_untrustedstring(ab, size,
- data);
+ if (size > 0 &&
+ ((unsigned char *)data)[size - 1] == '\0')
+ size--;
+ audit_log_n_untrustedstring(ab, data, size);
}
audit_set_pid(ab, pid);
audit_log_end(ab);
return -EINVAL;
if (audit_enabled == AUDIT_LOCKED) {
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " audit_enabled=%d res=0",
audit_enabled);
}
/* fallthrough */
case AUDIT_LIST:
- err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
+ err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
uid, seq, data, nlmsg_len(nlh),
- loginuid, sid);
+ loginuid, sessionid, sid);
break;
case AUDIT_ADD_RULE:
case AUDIT_DEL_RULE:
return -EINVAL;
if (audit_enabled == AUDIT_LOCKED) {
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " audit_enabled=%d res=0",
audit_enabled);
}
/* fallthrough */
case AUDIT_LIST_RULES:
- err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
+ err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
uid, seq, data, nlmsg_len(nlh),
- loginuid, sid);
+ loginuid, sessionid, sid);
break;
case AUDIT_TRIM:
audit_trim_trees();
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " op=trim res=1");
audit_log_end(ab);
case AUDIT_MAKE_EQUIV: {
void *bufp = data;
u32 sizes[2];
- size_t len = nlmsg_len(nlh);
+ size_t msglen = nlmsg_len(nlh);
char *old, *new;
err = -EINVAL;
- if (len < 2 * sizeof(u32))
+ if (msglen < 2 * sizeof(u32))
break;
memcpy(sizes, bufp, 2 * sizeof(u32));
bufp += 2 * sizeof(u32);
- len -= 2 * sizeof(u32);
- old = audit_unpack_string(&bufp, &len, sizes[0]);
+ msglen -= 2 * sizeof(u32);
+ old = audit_unpack_string(&bufp, &msglen, sizes[0]);
if (IS_ERR(old)) {
err = PTR_ERR(old);
break;
}
- new = audit_unpack_string(&bufp, &len, sizes[1]);
+ new = audit_unpack_string(&bufp, &msglen, sizes[1]);
if (IS_ERR(new)) {
err = PTR_ERR(new);
kfree(old);
err = audit_tag_tree(old, new);
audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
- uid, loginuid, sid);
+ uid, loginuid, sessionid, sid);
audit_log_format(ab, " op=make_equiv old=");
audit_log_untrustedstring(ab, old);
break;
}
case AUDIT_SIGNAL_INFO:
- err = selinux_sid_to_string(audit_sig_sid, &ctx, &len);
- if (err)
- return err;
+ len = 0;
+ if (audit_sig_sid) {
+ err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
+ if (err)
+ return err;
+ }
sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
if (!sig_data) {
- kfree(ctx);
+ if (audit_sig_sid)
+ security_release_secctx(ctx, len);
return -ENOMEM;
}
sig_data->uid = audit_sig_uid;
sig_data->pid = audit_sig_pid;
- memcpy(sig_data->ctx, ctx, len);
- kfree(ctx);
+ if (audit_sig_sid) {
+ memcpy(sig_data->ctx, ctx, len);
+ security_release_secctx(ctx, len);
+ }
audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
0, 0, sig_data, sizeof(*sig_data) + len);
kfree(sig_data);
case AUDIT_TTY_GET: {
struct audit_tty_status s;
struct task_struct *tsk;
+ unsigned long flags;
- read_lock(&tasklist_lock);
- tsk = find_task_by_pid(pid);
- if (!tsk)
- err = -ESRCH;
- else {
- spin_lock_irq(&tsk->sighand->siglock);
+ rcu_read_lock();
+ tsk = find_task_by_vpid(pid);
+ if (tsk && lock_task_sighand(tsk, &flags)) {
s.enabled = tsk->signal->audit_tty != 0;
- spin_unlock_irq(&tsk->sighand->siglock);
- }
- read_unlock(&tasklist_lock);
- audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_TTY_GET, 0, 0,
- &s, sizeof(s));
+ unlock_task_sighand(tsk, &flags);
+ } else
+ err = -ESRCH;
+ rcu_read_unlock();
+
+ if (!err)
+ audit_send_reply(NETLINK_CB(skb).pid, seq,
+ AUDIT_TTY_GET, 0, 0, &s, sizeof(s));
break;
}
case AUDIT_TTY_SET: {
struct audit_tty_status *s;
struct task_struct *tsk;
+ unsigned long flags;
if (nlh->nlmsg_len < sizeof(struct audit_tty_status))
return -EINVAL;
s = data;
if (s->enabled != 0 && s->enabled != 1)
return -EINVAL;
- read_lock(&tasklist_lock);
- tsk = find_task_by_pid(pid);
- if (!tsk)
- err = -ESRCH;
- else {
- spin_lock_irq(&tsk->sighand->siglock);
+ rcu_read_lock();
+ tsk = find_task_by_vpid(pid);
+ if (tsk && lock_task_sighand(tsk, &flags)) {
tsk->signal->audit_tty = s->enabled != 0;
- spin_unlock_irq(&tsk->sighand->siglock);
- }
- read_unlock(&tasklist_lock);
+ unlock_task_sighand(tsk, &flags);
+ } else
+ err = -ESRCH;
+ rcu_read_unlock();
break;
}
default:
}
/*
- * 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.
+ * Get message from skb. Each message is processed by audit_receive_msg.
+ * Malformed skbs with wrong length are discarded silently.
*/
static void audit_receive_skb(struct sk_buff *skb)
{
- int err;
- struct nlmsghdr *nlh;
- u32 rlen;
+ struct nlmsghdr *nlh;
+ /*
+ * len MUST be signed for NLMSG_NEXT to be able to dec it below 0
+ * if the nlmsg_len was not aligned
+ */
+ int len;
+ int err;
- while (skb->len >= NLMSG_SPACE(0)) {
- nlh = nlmsg_hdr(skb);
- if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
- return;
- rlen = NLMSG_ALIGN(nlh->nlmsg_len);
- if (rlen > skb->len)
- rlen = skb->len;
- if ((err = audit_receive_msg(skb, nlh))) {
+ nlh = nlmsg_hdr(skb);
+ len = skb->len;
+
+ while (NLMSG_OK(nlh, len)) {
+ err = audit_receive_msg(skb, nlh);
+ /* if err or if this message says it wants a response */
+ if (err || (nlh->nlmsg_flags & NLM_F_ACK))
netlink_ack(skb, nlh, err);
- } else if (nlh->nlmsg_flags & NLM_F_ACK)
- netlink_ack(skb, nlh, 0);
- skb_pull(skb, rlen);
+
+ nlh = NLMSG_NEXT(nlh, len);
}
}
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)
{
int i;
+ if (audit_initialized == AUDIT_DISABLED)
+ return 0;
+
printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
audit_default ? "enabled" : "disabled");
audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, 0,
audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
skb_queue_head_init(&audit_skb_queue);
- audit_initialized = 1;
+ skb_queue_head_init(&audit_skb_hold_queue);
+ audit_initialized = AUDIT_INITIALIZED;
audit_enabled = audit_default;
audit_ever_enabled |= !!audit_default;
- /* Register the callback with selinux. This callback will be invoked
- * when a new policy is loaded. */
- 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");
-#endif
-
for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
INIT_LIST_HEAD(&audit_inode_hash[i]);
static int __init audit_enable(char *str)
{
audit_default = !!simple_strtol(str, NULL, 0);
- printk(KERN_INFO "audit: %s%s\n",
- audit_default ? "enabled" : "disabled",
- audit_initialized ? "" : " (after initialization)");
- if (audit_initialized) {
+ if (!audit_default)
+ audit_initialized = AUDIT_DISABLED;
+
+ printk(KERN_INFO "audit: %s", audit_default ? "enabled" : "disabled");
+
+ if (audit_initialized == AUDIT_INITIALIZED) {
audit_enabled = audit_default;
audit_ever_enabled |= !!audit_default;
+ } else if (audit_initialized == AUDIT_UNINITIALIZED) {
+ printk(" (after initialization)");
+ } else {
+ printk(" (until reboot)");
}
+ printk("\n");
+
return 1;
}
goto err;
}
- ab->skb = alloc_skb(AUDIT_BUFSIZ, gfp_mask);
- if (!ab->skb)
- goto err;
-
ab->ctx = ctx;
ab->gfp_mask = gfp_mask;
- nlh = (struct nlmsghdr *)skb_put(ab->skb, NLMSG_SPACE(0));
- nlh->nlmsg_type = type;
- nlh->nlmsg_flags = 0;
- nlh->nlmsg_pid = 0;
- nlh->nlmsg_seq = 0;
+
+ ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask);
+ if (!ab->skb)
+ goto nlmsg_failure;
+
+ nlh = NLMSG_NEW(ab->skb, 0, 0, type, 0, 0);
+
return ab;
+
+nlmsg_failure: /* Used by NLMSG_NEW */
+ kfree_skb(ab->skb);
+ ab->skb = NULL;
err:
audit_buffer_free(ab);
return NULL;
static inline void audit_get_stamp(struct audit_context *ctx,
struct timespec *t, unsigned int *serial)
{
- if (ctx)
- auditsc_get_stamp(ctx, t, serial);
- else {
+ if (!ctx || !auditsc_get_stamp(ctx, t, serial)) {
*t = CURRENT_TIME;
*serial = audit_serial();
}
int reserve;
unsigned long timeout_start = jiffies;
- if (!audit_initialized)
+ if (audit_initialized != AUDIT_INITIALIZED)
return NULL;
if (unlikely(audit_filter_type(type)))
* 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,
+void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
size_t len)
{
int i, avail, new_len;
* 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)
+void audit_log_n_string(struct audit_buffer *ab, const char *string,
+ size_t slen)
{
int avail, new_len;
unsigned char *ptr;
/**
* audit_string_contains_control - does a string need to be logged in hex
- * @string - string to be checked
- * @len - max length of the string to check
+ * @string: string to be checked
+ * @len: max length of the string to check
*/
int audit_string_contains_control(const char *string, size_t len)
{
const unsigned char *p;
- for (p = string; p < (const unsigned char *)string + len && *p; p++) {
- if (*p == '"' || *p < 0x21 || *p > 0x7f)
+ for (p = string; p < (const unsigned char *)string + len; p++) {
+ if (*p == '"' || *p < 0x21 || *p > 0x7e)
return 1;
}
return 0;
/**
* audit_log_n_untrustedstring - log a string that may contain random characters
* @ab: audit_buffer
- * @len: lenth of string (not including trailing null)
+ * @len: length 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
* The caller specifies the number of characters in the string to log, which may
* or may not be the entire string.
*/
-void audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len,
- const char *string)
+void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
+ size_t len)
{
if (audit_string_contains_control(string, len))
- audit_log_hex(ab, string, len);
+ audit_log_n_hex(ab, string, len);
else
- audit_log_n_string(ab, len, string);
+ audit_log_n_string(ab, string, len);
}
/**
*/
void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
{
- audit_log_n_untrustedstring(ab, strlen(string), string);
+ audit_log_n_untrustedstring(ab, string, strlen(string));
}
/* This is a helper-function to print the escaped d_path */
/* We will allow 11 spaces for ' (deleted)' to be appended */
pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
if (!pathname) {
- audit_log_format(ab, "<no memory>");
+ audit_log_string(ab, "<no_memory>");
return;
}
- p = d_path(path->dentry, path->mnt, pathname, PATH_MAX+11);
+ p = d_path(path, pathname, PATH_MAX+11);
if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
/* FIXME: can we save some information here? */
- audit_log_format(ab, "<too long>");
+ audit_log_string(ab, "<too_long>");
} else
audit_log_untrustedstring(ab, p);
kfree(pathname);
}
+void audit_log_key(struct audit_buffer *ab, char *key)
+{
+ audit_log_format(ab, " key=");
+ if (key)
+ audit_log_untrustedstring(ab, key);
+ else
+ audit_log_format(ab, "(null)");
+}
+
/**
* audit_log_end - end one audit record
* @ab: the audit_buffer
if (!audit_rate_check()) {
audit_log_lost("rate limit exceeded");
} else {
+ struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
+ nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
+
if (audit_pid) {
- struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
- nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
skb_queue_tail(&audit_skb_queue, ab->skb);
- ab->skb = NULL;
wake_up_interruptible(&kauditd_wait);
- } else if (printk_ratelimit()) {
- struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
- printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, ab->skb->data + NLMSG_SPACE(0));
} else {
- audit_log_lost("printk limit exceeded\n");
+ audit_printk_skb(ab->skb);
}
+ ab->skb = NULL;
}
audit_buffer_free(ab);
}
}
}
+#ifdef CONFIG_SECURITY
+/**
+ * audit_log_secctx - Converts and logs SELinux context
+ * @ab: audit_buffer
+ * @secid: security number
+ *
+ * This is a helper function that calls security_secid_to_secctx to convert
+ * secid to secctx and then adds the (converted) SELinux context to the audit
+ * log by calling audit_log_format, thus also preventing leak of internal secid
+ * to userspace. If secid cannot be converted audit_panic is called.
+ */
+void audit_log_secctx(struct audit_buffer *ab, u32 secid)
+{
+ u32 len;
+ char *secctx;
+
+ if (security_secid_to_secctx(secid, &secctx, &len)) {
+ audit_panic("Cannot convert secid to context");
+ } else {
+ audit_log_format(ab, " obj=%s", secctx);
+ security_release_secctx(secctx, len);
+ }
+}
+EXPORT_SYMBOL(audit_log_secctx);
+#endif
+
EXPORT_SYMBOL(audit_log_start);
EXPORT_SYMBOL(audit_log_end);
EXPORT_SYMBOL(audit_log_format);
Code Review / linux-2.6.git / blobdiff