[RFC PATCH] audit: Add generic compat syscall support
lib/audit.c provides a generic definition for auditing system calls.
lib/compat_audit.c similarly adds compat syscall support for
bi-architectures (32/64-bit).
Each architecture must define audit_is_compat() in asm/audit.h.
Signed-off-by: AKASHI Takahiro <takahiro.akashi(a)linaro.org>
---
include/linux/audit.h | 3 +++
lib/Makefile | 3 +++
lib/audit.c | 10 ++++++++
lib/compat_audit.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 80 insertions(+)
create mode 100644 lib/compat_audit.c
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 729a4d1..f6c8d18 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -75,6 +75,9 @@ struct audit_field {
extern int __init audit_register_class(int class, unsigned *list);
extern int audit_classify_syscall(int abi, unsigned syscall);
+#ifdef CONFIG_COMPAT
+extern int audit_classify_compat_syscall(int abi, unsigned syscall);
+#endif
extern int audit_classify_arch(int arch);
/* audit_names->type values */
diff --git a/lib/Makefile b/lib/Makefile
index f3bb2cb..5bb185a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -96,6 +96,9 @@ obj-$(CONFIG_TEXTSEARCH_BM) += ts_bm.o
obj-$(CONFIG_TEXTSEARCH_FSM) += ts_fsm.o
obj-$(CONFIG_SMP) += percpu_counter.o
obj-$(CONFIG_AUDIT_GENERIC) += audit.o
+ifeq ($(CONFIG_COMPAT),y)
+obj-$(CONFIG_AUDIT_GENERIC) += compat_audit.o
+endif
obj-$(CONFIG_SWIOTLB) += swiotlb.o
obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o
diff --git a/lib/audit.c b/lib/audit.c
index 76bbed4..fa373bd 100644
--- a/lib/audit.c
+++ b/lib/audit.c
@@ -1,6 +1,7 @@
#include <linux/init.h>
#include <linux/types.h>
#include <linux/audit.h>
+#include <asm/audit.h>
#include <asm/unistd.h>
static unsigned dir_class[] = {
@@ -30,11 +31,20 @@ static unsigned signal_class[] = {
int audit_classify_arch(int arch)
{
+#ifdef CONFIG_COMPAT
+ if (audit_is_compat(arch))
+ return 1;
+#endif
return 0;
}
int audit_classify_syscall(int abi, unsigned syscall)
{
+#ifdef CONFIG_COMPAT
+ if (audit_is_compat(abi))
+ return audit_classify_compat_syscall(abi, syscall);
+#endif
+
switch(syscall) {
#ifdef __NR_open
case __NR_open:
diff --git a/lib/compat_audit.c b/lib/compat_audit.c
new file mode 100644
index 0000000..837a6e6
--- /dev/null
+++ b/lib/compat_audit.c
@@ -0,0 +1,64 @@
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/audit.h>
+/* FIXME: this might be architecture dependent */
+#include <asm/unistd_32.h>
+
+static unsigned compat_dir_class[] = {
+#include <asm-generic/audit_dir_write.h>
+~0U
+};
+
+static unsigned compat_read_class[] = {
+#include <asm-generic/audit_read.h>
+~0U
+};
+
+static unsigned compat_write_class[] = {
+#include <asm-generic/audit_write.h>
+~0U
+};
+
+static unsigned compat_chattr_class[] = {
+#include <asm-generic/audit_change_attr.h>
+~0U
+};
+
+static unsigned compat_signal_class[] = {
+#include <asm-generic/audit_signal.h>
+~0U
+};
+
+int audit_classify_compat_syscall(int abi, unsigned syscall)
+{
+ switch(syscall) {
+#ifdef __NR_open
+ case __NR_open:
+ return 2;
+#endif
+#ifdef __NR_openat
+ case __NR_openat:
+ return 3;
+#endif
+#ifdef __NR_socketcall
+ case __NR_socketcall:
+ return 4;
+#endif
+ case __NR_execve:
+ return 5;
+ default:
+ return 1;
+ }
+}
+
+static int __init audit_compat_classes_init(void)
+{
+ audit_register_class(AUDIT_CLASS_WRITE, compat_write_class);
+ audit_register_class(AUDIT_CLASS_READ, compat_read_class);
+ audit_register_class(AUDIT_CLASS_DIR_WRITE, compat_dir_class);
+ audit_register_class(AUDIT_CLASS_CHATTR, compat_chattr_class);
+ audit_register_class(AUDIT_CLASS_SIGNAL, compat_signal_class);
+ return 0;
+}
+
+__initcall(audit_compat_classes_init);
--
1.7.9.5