c51cd5fe91
Before safecopies, the IO_ENDPT and DL_ENDPT message fields were needed to know which actual process to copy data from/to, as that process may not always be the caller. Now that we have full safecopy support, these fields have become useless for that purpose: the owner of the grant is *always* the caller. Allowing the caller to supply another endpoint is in fact dangerous, because the callee may then end up using a grant from a third party. One could call this a variant of the confused deputy problem. From now on, safecopy calls should always use the caller's endpoint as grant owner. This fully obsoletes the DL_ENDPT field in the inet/ethernet protocol. IO_ENDPT has other uses besides identifying the grant owner though. This patch renames IO_ENDPT to USER_ENDPT, not only because that is a more fitting name (it should never be used for I/O after all), but also in order to intentionally break any old system source code outside the base system. If this patch breaks your code, fixing it is fairly simple: - DL_ENDPT should be replaced with m_source; - IO_ENDPT should be replaced with m_source when used for safecopies; - IO_ENDPT should be replaced with USER_ENDPT for any other use, e.g. when setting REP_ENDPT, matching requests in CANCEL calls, getting DEV_SELECT flags, and retrieving of the real user process's endpoint in DEV_OPEN. The changes in this patch are binary backward compatible.
15 lines
440 B
C
15 lines
440 B
C
#include "syslib.h"
|
|
|
|
/*===========================================================================*
|
|
* sys_enable_iop *
|
|
*===========================================================================*/
|
|
PUBLIC int sys_enable_iop(proc_ep)
|
|
endpoint_t proc_ep; /* number of process to allow I/O */
|
|
{
|
|
message m_iop;
|
|
m_iop.IOP_ENDPT = proc_ep;
|
|
return _kernel_call(SYS_IOPENABLE, &m_iop);
|
|
}
|
|
|
|
|