[XSM][FLASK] Argument handling bugs in XSM:FLASK

Addresses a number of argument handling bugs in the flask_op hypercall
in the XSM:Flask module.  Thanks to Rafal Wojtczuk at McAfee for
reporting the issues and Tim Deegan at Citrix for providing an
initial patch.

This patch addresses the following issues:
 - bounds checking and validation on input arguments to flask_op
 - updated ABI/API, size and cmd are now uint32_t
 - updated userspace tools and libraries to account for ABI/API
 changes
 - implemented all copies using from/to guest, better portability
 - implemented upper bounds checking on op->cmd, op->size
 - implemented sanity checking on op->size and op->buf
 - implemented bit vector for checking from/to usage on op->cmd

Signed-off-by: George Coker <gscoker@alpha.ncsc.mil>

1 files changed, 3 insertions, 3 deletions

diff --git a/tools/flask/libflask/include/flask.h b/tools/flask/libflask/include/flask.h
index 5973933ac8..5241f7a2a0 100644
--- a/tools/flask/libflask/include/flask.h
+++ b/tools/flask/libflask/include/flask.h
@@ -15,8 +15,8 @@
 #include <xen/xen.h>
 #include <xen/xsm/flask_op.h>
 
-int flask_load(int xc_handle, char *buf, int size);
-int flask_context_to_sid(int xc_handle, char *buf, int size, uint32_t *sid);
-int flask_sid_to_context(int xc_handle, int sid, char *buf, int size);
+int flask_load(int xc_handle, char *buf, uint32_t size);
+int flask_context_to_sid(int xc_handle, char *buf, uint32_t size, uint32_t *sid);
+int flask_sid_to_context(int xc_handle, int sid, char *buf, uint32_t size);
 
 #endif /* __FLASK_H__ */