Add support for extended header BSM tokens. Currently we use the

regular header tokens.  The extended header tokens contain an IP
or IPv6 address which makes it possible to identify which host an
audit record came from when audit records are centralized.

If the host information has not been specified, the system will
default to the old style headers.  Otherwise, audit records that
are created as a result of system calls will contain host information.

This implemented has been designed to be consistent with the Solaris
implementation.  Host information is set/retrieved using the A_GETKAUDIT
and A_SETKAUDIT auditon(2) commands.  These commands require that a
pointer to a auditinfo_addr_t object is passed.  Currently only IP and
IPv6 address families are supported.

The users pace bits associated with this change will follow in an
openbsm import.

Reviewed by:	rwatson, (sson, wsalamon (older version))
MFC after:	1 month

1 files changed, 43 insertions, 0 deletions

diff --git a/sys/security/audit/audit.c b/sys/security/audit/audit.c
index 737c693..8680ad3 100644
--- a/sys/security/audit/audit.c
+++ b/sys/security/audit/audit.c
@@ -158,6 +158,45 @@ struct cv		audit_watermark_cv;
 static struct cv	audit_fail_cv;
 
 /*
+ * Kernel audit information.  This will store the current audit address
+ * or host information that the kernel will use when it's generating
+ * audit records.  This data is modified by the A_GET{SET}KAUDIT auditon(2)
+ * command.
+ */
+static struct auditinfo_addr	audit_kinfo;
+static struct rwlock		audit_kinfo_lock;
+
+#define	KINFO_LOCK_INIT()	rw_init(&audit_kinfo_lock, "kernel audit info lock")
+#define	KINFO_RLOCK()		rw_rlock(&audit_kinfo_lock)
+#define	KINFO_WLOCK()		rw_wlock(&audit_kinfo_lock)
+#define	KINFO_RUNLOCK()		rw_runlock(&audit_kinfo_lock)
+#define	KINFO_WUNLOCK()		rw_wunlock(&audit_kinfo_lock)
+
+void
+audit_set_kinfo(struct auditinfo_addr *ak)
+{
+
+	KASSERT(ak->ai_termid.at_type == AU_IPv4 ||
+	    ak->ai_termid.at_type == AU_IPv6,
+	    ("audit_set_kinfo: invalid address type"));
+	KINFO_WLOCK();
+	audit_kinfo = *ak;
+	KINFO_WUNLOCK();
+}
+
+void
+audit_get_kinfo(struct auditinfo_addr *ak)
+{
+
+	KASSERT(audit_kinfo.ai_termid.at_type == AU_IPv4 ||
+	    audit_kinfo.ai_termid.at_type == AU_IPv6,
+	    ("audit_set_kinfo: invalid address type"));
+	KINFO_RLOCK();
+	*ak = audit_kinfo;
+	KINFO_RUNLOCK();
+}
+
+/*
  * Construct an audit record for the passed thread.
  */
 static int
@@ -241,7 +280,11 @@ audit_init(void)
 	audit_qctrl.aq_bufsz = AQ_BUFSZ;
 	audit_qctrl.aq_minfree = AU_FS_MINFREE;
 
+	audit_kinfo.ai_termid.at_type = AU_IPv4;
+	audit_kinfo.ai_termid.at_addr[0] = INADDR_ANY;
+
 	mtx_init(&audit_mtx, "audit_mtx", NULL, MTX_DEF);
+	KINFO_LOCK_INIT();
 	cv_init(&audit_worker_cv, "audit_worker_cv");
 	cv_init(&audit_watermark_cv, "audit_watermark_cv");
 	cv_init(&audit_fail_cv, "audit_fail_cv");