[AUDIT] add session id to audit messages

In order to correlate audit records to an individual login add a session
id.  This is incremented every time a user logs in and is included in
almost all messages which currently output the auid.  The field is
labeled ses=  or oses=

Signed-off-by: Eric Paris <eparis@redhat.com>

drivers/char/tty_audit.c

@@ -73,6 +73,7 @@ static void tty_audit_buf_put(struct tty_audit_buf *buf)
  *	@tsk with @loginuid.  @buf->mutex must be locked.
  */
 static void tty_audit_buf_push(struct task_struct *tsk, uid_t loginuid,
+			       unsigned int sessionid,
 			       struct tty_audit_buf *buf)
 {
 	struct audit_buffer *ab;
@@ -85,9 +86,9 @@ static void tty_audit_buf_push(struct task_struct *tsk, uid_t loginuid,
 	if (ab) {
 		char name[sizeof(tsk->comm)];
 
-		audit_log_format(ab, "tty pid=%u uid=%u auid=%u major=%d "
-				 "minor=%d comm=", tsk->pid, tsk->uid,
-				 loginuid, buf->major, buf->minor);
+		audit_log_format(ab, "tty pid=%u uid=%u auid=%u ses=%u "
+				 "major=%d minor=%d comm=", tsk->pid, tsk->uid,
+				 loginuid, sessionid, buf->major, buf->minor);
 		get_task_comm(name, tsk);
 		audit_log_untrustedstring(ab, name);
 		audit_log_format(ab, " data=");
@@ -105,7 +106,9 @@ static void tty_audit_buf_push(struct task_struct *tsk, uid_t loginuid,
  */
 static void tty_audit_buf_push_current(struct tty_audit_buf *buf)
 {
-	tty_audit_buf_push(current, audit_get_loginuid(current), buf);
+	uid_t auid = audit_get_loginuid(current);
+	unsigned int sessionid = audit_get_sessionid(current);
+	tty_audit_buf_push(current, auid, sessionid, buf);
 }
 
 /**
@@ -151,6 +154,11 @@ void tty_audit_fork(struct signal_struct *sig)
 void tty_audit_push_task(struct task_struct *tsk, uid_t loginuid)
 {
 	struct tty_audit_buf *buf;
+	/* FIXME I think this is correct.  Check against netlink once that is
+	 * I really need to read this code more closely.  But that's for
+	 * another patch.
+	 */
+	unsigned int sessionid = audit_get_sessionid(tsk);
 
 	spin_lock_irq(&tsk->sighand->siglock);
 	buf = tsk->signal->tty_audit_buf;
@@ -161,7 +169,7 @@ void tty_audit_push_task(struct task_struct *tsk, uid_t loginuid)
 		return;
 
 	mutex_lock(&buf->mutex);
-	tty_audit_buf_push(tsk, loginuid, buf);
+	tty_audit_buf_push(tsk, loginuid, sessionid, buf);
 	mutex_unlock(&buf->mutex);
 
 	tty_audit_buf_put(buf);

include/linux/audit.h

@@ -410,6 +410,7 @@ extern void auditsc_get_stamp(struct audit_context *ctx,
 			      struct timespec *t, unsigned int *serial);
 extern int  audit_set_loginuid(struct task_struct *task, uid_t loginuid);
 #define audit_get_loginuid(t) ((t)->loginuid)
+#define audit_get_sessionid(t) ((t)->sessionid)
 extern void audit_log_task_context(struct audit_buffer *ab);
 extern int __audit_ipc_obj(struct kern_ipc_perm *ipcp);
 extern int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode);
@@ -489,6 +490,7 @@ extern int audit_signals;
 #define audit_core_dumps(i) do { ; } while (0)
 #define auditsc_get_stamp(c,t,s) do { BUG(); } while (0)
 #define audit_get_loginuid(t) (-1)
+#define audit_get_sessionid(t) (-1)
 #define audit_log_task_context(b) do { ; } while (0)
 #define audit_ipc_obj(i) ({ 0; })
 #define audit_ipc_set_perm(q,u,g,m) ({ 0; })

include/linux/init_task.h

@@ -116,7 +116,8 @@ extern struct group_info init_groups;
 
 #ifdef CONFIG_AUDITSYSCALL
 #define INIT_IDS \
-	.loginuid = -1,
+	.loginuid = -1, \
+	.sessionid = -1,
 #else
 #define INIT_IDS
 #endif

include/linux/sched.h

@@ -1141,6 +1141,7 @@ struct task_struct {
 	struct audit_context *audit_context;
 #ifdef CONFIG_AUDITSYSCALL
 	uid_t loginuid;
+	unsigned int sessionid;
 #endif
 	seccomp_t seccomp;
 

kernel/auditsc.c

@@ -178,6 +178,7 @@ struct audit_aux_data_pids {
 	pid_t			target_pid[AUDIT_AUX_PIDS];
 	uid_t			target_auid[AUDIT_AUX_PIDS];
 	uid_t			target_uid[AUDIT_AUX_PIDS];
+	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
 	u32			target_sid[AUDIT_AUX_PIDS];
 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
 	int			pid_count;
@@ -219,6 +220,7 @@ struct audit_context {
 	pid_t		    target_pid;
 	uid_t		    target_auid;
 	uid_t		    target_uid;
+	unsigned int	    target_sessionid;
 	u32		    target_sid;
 	char		    target_comm[TASK_COMM_LEN];
 
@@ -936,7 +938,8 @@ static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk
 }
 
 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
-				 uid_t auid, uid_t uid, u32 sid, char *comm)
+				 uid_t auid, uid_t uid, unsigned int sessionid,
+				 u32 sid, char *comm)
 {
 	struct audit_buffer *ab;
 	char *s = NULL;
@@ -947,7 +950,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 	if (!ab)
 		return 1;
 
-	audit_log_format(ab, "opid=%d oauid=%d ouid=%d", pid, auid, uid);
+	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid,
+			 uid, sessionid);
 	if (selinux_sid_to_string(sid, &s, &len)) {
 		audit_log_format(ab, " obj=(none)");
 		rc = 1;
@@ -1056,7 +1060,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 		  " a0=%lx a1=%lx a2=%lx a3=%lx items=%d"
 		  " ppid=%d pid=%d auid=%u uid=%u gid=%u"
 		  " euid=%u suid=%u fsuid=%u"
-		  " egid=%u sgid=%u fsgid=%u tty=%s",
+		  " egid=%u sgid=%u fsgid=%u tty=%s ses=%u",
 		  context->argv[0],
 		  context->argv[1],
 		  context->argv[2],
@@ -1068,7 +1072,8 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 		  context->uid,
 		  context->gid,
 		  context->euid, context->suid, context->fsuid,
-		  context->egid, context->sgid, context->fsgid, tty);
+		  context->egid, context->sgid, context->fsgid, tty,
+		  tsk->sessionid);
 
 	mutex_unlock(&tty_mutex);
 
@@ -1187,6 +1192,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 			if (audit_log_pid_context(context, axs->target_pid[i],
 						  axs->target_auid[i],
 						  axs->target_uid[i],
+						  axs->target_sessionid[i],
 						  axs->target_sid[i],
 						  axs->target_comm[i]))
 				call_panic = 1;
@@ -1195,6 +1201,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 	if (context->target_pid &&
 	    audit_log_pid_context(context, context->target_pid,
 				  context->target_auid, context->target_uid,
+				  context->target_sessionid,
 				  context->target_sid, context->target_comm))
 			call_panic = 1;
 
@@ -1787,6 +1794,9 @@ void auditsc_get_stamp(struct audit_context *ctx,
 	ctx->auditable = 1;
 }
 
+/* global counter which is incremented every time something logs in */
+static atomic_t session_id = ATOMIC_INIT(0);
+
 /**
  * audit_set_loginuid - set a task's audit_context loginuid
  * @task: task whose audit context is being modified
@@ -1798,6 +1808,7 @@ void auditsc_get_stamp(struct audit_context *ctx,
  */
 int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
 {
+	unsigned int sessionid = atomic_inc_return(&session_id);
 	struct audit_context *context = task->audit_context;
 
 	if (context && context->in_syscall) {
@@ -1806,12 +1817,15 @@ int audit_set_loginuid(struct task_struct *task, uid_t loginuid)
 		ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
 		if (ab) {
 			audit_log_format(ab, "login pid=%d uid=%u "
-				"old auid=%u new auid=%u",
+				"old auid=%u new auid=%u"
+				" old ses=%u new ses=%u",
 				task->pid, task->uid,
-				task->loginuid, loginuid);
+				task->loginuid, loginuid,
+				task->sessionid, sessionid);
 			audit_log_end(ab);
 		}
 	}
+	task->sessionid = sessionid;
 	task->loginuid = loginuid;
 	return 0;
 }
@@ -2200,6 +2214,7 @@ void __audit_ptrace(struct task_struct *t)
 	context->target_pid = t->pid;
 	context->target_auid = audit_get_loginuid(t);
 	context->target_uid = t->uid;
+	context->target_sessionid = audit_get_sessionid(t);
 	selinux_get_task_sid(t, &context->target_sid);
 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
 }
@@ -2240,6 +2255,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
 		ctx->target_pid = t->tgid;
 		ctx->target_auid = audit_get_loginuid(t);
 		ctx->target_uid = t->uid;
+		ctx->target_sessionid = audit_get_sessionid(t);
 		selinux_get_task_sid(t, &ctx->target_sid);
 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
 		return 0;
@@ -2260,6 +2276,7 @@ int __audit_signal_info(int sig, struct task_struct *t)
 	axp->target_pid[axp->pid_count] = t->tgid;
 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
 	axp->target_uid[axp->pid_count] = t->uid;
+	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
 	selinux_get_task_sid(t, &axp->target_sid[axp->pid_count]);
 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
 	axp->pid_count++;
@@ -2278,6 +2295,8 @@ void audit_core_dumps(long signr)
 {
 	struct audit_buffer *ab;
 	u32 sid;
+	uid_t auid = audit_get_loginuid(current);
+	unsigned int sessionid = audit_get_sessionid(current);
 
 	if (!audit_enabled)
 		return;
@@ -2286,9 +2305,8 @@ void audit_core_dumps(long signr)
 		return;
 
 	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
-	audit_log_format(ab, "auid=%u uid=%u gid=%u",
-			audit_get_loginuid(current),
-			current->uid, current->gid);
+	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
+			auid, current->uid, current->gid, sessionid);
 	selinux_get_task_sid(current, &sid);
 	if (sid) {
 		char *ctx = NULL;

net/core/dev.c

@@ -2754,10 +2754,11 @@ static void __dev_set_promiscuity(struct net_device *dev, int inc)
 							       "left");
 		audit_log(current->audit_context, GFP_ATOMIC,
 			AUDIT_ANOM_PROMISCUOUS,
-			"dev=%s prom=%d old_prom=%d auid=%u",
+			"dev=%s prom=%d old_prom=%d auid=%u ses=%u",
 			dev->name, (dev->flags & IFF_PROMISC),
 			(old_flags & IFF_PROMISC),
-			audit_get_loginuid(current));
+			audit_get_loginuid(current),
+			audit_get_sessionid(current));
 
 		if (dev->change_rx_flags)
 			dev->change_rx_flags(dev, IFF_PROMISC);

security/selinux/selinuxfs.c

@@ -172,9 +172,10 @@ static ssize_t sel_write_enforce(struct file * file, const char __user * buf,
 		if (length)
 			goto out;
 		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
-			"enforcing=%d old_enforcing=%d auid=%u", new_value, 
-			selinux_enforcing,
-			audit_get_loginuid(current));
+			"enforcing=%d old_enforcing=%d auid=%u ses=%u",
+			new_value, selinux_enforcing,
+			audit_get_loginuid(current),
+			audit_get_sessionid(current));
 		selinux_enforcing = new_value;
 		if (selinux_enforcing)
 			avc_ss_reset(0);
@@ -243,8 +244,9 @@ static ssize_t sel_write_disable(struct file * file, const char __user * buf,
 		if (length < 0)
 			goto out;
 		audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_STATUS,
-			"selinux=0 auid=%u",
-			audit_get_loginuid(current));
+			"selinux=0 auid=%u ses=%u",
+			audit_get_loginuid(current),
+			audit_get_sessionid(current));
 	}
 
 	length = count;
@@ -356,8 +358,9 @@ static ssize_t sel_write_load(struct file * file, const char __user * buf,
 		(security_get_allow_unknown() ? "allow" : "deny")));
 
 	audit_log(current->audit_context, GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
-		"policy loaded auid=%u",
-		audit_get_loginuid(current));
+		"policy loaded auid=%u ses=%u",
+		audit_get_loginuid(current),
+		audit_get_sessionid(current));
 out:
 	mutex_unlock(&sel_mutex);
 	vfree(data);

security/selinux/ss/services.c

@@ -1905,11 +1905,12 @@ int security_set_bools(int len, int *values)
 		if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
 			audit_log(current->audit_context, GFP_ATOMIC,
 				AUDIT_MAC_CONFIG_CHANGE,
-				"bool=%s val=%d old_val=%d auid=%u",
+				"bool=%s val=%d old_val=%d auid=%u ses=%u",
 				policydb.p_bool_val_to_name[i],
 				!!values[i],
 				policydb.bool_val_to_struct[i]->state,
-				audit_get_loginuid(current));
+				audit_get_loginuid(current),
+				audit_get_sessionid(current));
 		}
 		if (values[i]) {
 			policydb.bool_val_to_struct[i]->state = 1;