minix/kernel/system/do_privctl.c
2007-02-16 15:53:10 +00:00

229 lines
6.4 KiB
C

/* The kernel call implemented in this file:
* m_type: SYS_PRIVCTL
*
* The parameters for this kernel call are:
* m1_i1: PR_ENDPT (process number of caller)
*/
#include "../system.h"
#include "../ipc.h"
#include <signal.h>
#include <string.h>
#if USE_PRIVCTL
#define FILLED_MASK (~0)
/*===========================================================================*
* do_privctl *
*===========================================================================*/
PUBLIC int do_privctl(m_ptr)
message *m_ptr; /* pointer to request message */
{
/* Handle sys_privctl(). Update a process' privileges. If the process is not
* yet a system process, make sure it gets its own privilege structure.
*/
register struct proc *caller_ptr;
register struct proc *rp;
register struct priv *sp;
int proc_nr;
int priv_id;
int i;
phys_bytes caller_phys, kernel_phys;
struct io_range io_range;
struct mem_range mem_range;
struct priv priv;
/* Check whether caller is allowed to make this call. Privileged proceses
* can only update the privileges of processes that are inhibited from
* running by the NO_PRIV flag. This flag is set when a privileged process
* forks.
*/
caller_ptr = proc_addr(who_p);
if (! (priv(caller_ptr)->s_flags & SYS_PROC)) return(EPERM);
if(m_ptr->PR_ENDPT == SELF) proc_nr = who_p;
else if(!isokendpt(m_ptr->PR_ENDPT, &proc_nr)) return(EINVAL);
rp = proc_addr(proc_nr);
switch(m_ptr->CTL_REQUEST)
{
case SYS_PRIV_INIT:
if (! RTS_ISSET(rp, NO_PRIV)) return(EPERM);
/* Make sure this process has its own privileges structure. This may
* fail, since there are only a limited number of system processes.
* Then copy the privileges from the caller and restore some defaults.
*/
if ((i=get_priv(rp, SYS_PROC)) != OK) return(i);
priv_id = priv(rp)->s_id; /* backup privilege id */
*priv(rp) = *priv(caller_ptr); /* copy from caller */
priv(rp)->s_id = priv_id; /* restore privilege id */
priv(rp)->s_proc_nr = proc_nr; /* reassociate process nr */
for (i=0; i< BITMAP_CHUNKS(NR_SYS_PROCS); i++) /* remove pending: */
priv(rp)->s_notify_pending.chunk[i] = 0; /* - notifications */
priv(rp)->s_int_pending = 0; /* - interrupts */
sigemptyset(&priv(rp)->s_sig_pending); /* - signals */
/* Now update the process' privileges as requested. */
rp->p_priv->s_trap_mask = FILLED_MASK;
for (i=0; i<BITMAP_CHUNKS(NR_SYS_PROCS); i++) {
rp->p_priv->s_ipc_to.chunk[i] = FILLED_MASK;
}
unset_sys_bit(rp->p_priv->s_ipc_to, USER_PRIV_ID);
/* All process that this process can send to must be able to reply.
* Therefore, their send masks should be updated as well.
*/
for (i=0; i<NR_SYS_PROCS; i++) {
if (get_sys_bit(rp->p_priv->s_ipc_to, i)) {
set_sys_bit(priv_addr(i)->s_ipc_to, priv_id(rp));
}
}
/* No I/O resources, no memory resources, no IRQs, no grant table */
priv(rp)->s_nr_io_range= 0;
priv(rp)->s_nr_mem_range= 0;
priv(rp)->s_nr_irq= 0;
priv(rp)->s_grant_table= 0;
priv(rp)->s_grant_entries= 0;
if (m_ptr->CTL_ARG_PTR)
{
/* Copy privilege structure from caller */
caller_phys = umap_local(caller_ptr, D,
(vir_bytes) m_ptr->CTL_ARG_PTR, sizeof(priv));
if (caller_phys == 0)
return EFAULT;
kernel_phys = vir2phys(&priv);
phys_copy(caller_phys, kernel_phys, sizeof(priv));
/* Copy the call mask */
for (i= 0; i<CALL_MASK_SIZE; i++)
priv(rp)->s_k_call_mask[i]= priv.s_k_call_mask[i];
/* Copy IRQs */
if (priv.s_nr_irq < 0 || priv.s_nr_irq > NR_IRQ)
return EINVAL;
priv(rp)->s_nr_irq= priv.s_nr_irq;
for (i= 0; i<priv.s_nr_irq; i++)
{
priv(rp)->s_irq_tab[i]= priv.s_irq_tab[i];
#if 0
kprintf("do_privctl: adding IRQ %d\n",
priv(rp)->s_irq_tab[i]);
#endif
}
priv(rp)->s_flags |= CHECK_IRQ; /* Check requests for IRQs */
/* Copy I/O ranges */
if (priv.s_nr_io_range < 0 || priv.s_nr_io_range > NR_IO_RANGE)
return EINVAL;
priv(rp)->s_nr_io_range= priv.s_nr_io_range;
for (i= 0; i<priv.s_nr_io_range; i++)
{
priv(rp)->s_io_tab[i]= priv.s_io_tab[i];
#if 0
kprintf("do_privctl: adding I/O range [%x..%x]\n",
priv(rp)->s_io_tab[i].ior_base,
priv(rp)->s_io_tab[i].ior_limit);
#endif
}
/* Check requests for IRQs */
priv(rp)->s_flags |= CHECK_IO_PORT;
memcpy(priv(rp)->s_k_call_mask, priv.s_k_call_mask,
sizeof(priv(rp)->s_k_call_mask));
}
/* Done. Privileges have been set. Allow process to run again. */
RTS_LOCK_UNSET(rp, NO_PRIV);
return(OK);
case SYS_PRIV_USER:
/* Make this process an ordinary user process. */
if (!RTS_ISSET(rp, NO_PRIV)) return(EPERM);
if ((i=get_priv(rp, 0)) != OK) return(i);
RTS_LOCK_UNSET(rp, NO_PRIV);
return(OK);
case SYS_PRIV_ADD_IO:
if (RTS_ISSET(rp, NO_PRIV))
return(EPERM);
/* Only system processes get I/O resources? */
if (!(priv(rp)->s_flags & SYS_PROC))
return EPERM;
/* Get the I/O range */
caller_phys = umap_local(caller_ptr, D, (vir_bytes) m_ptr->CTL_ARG_PTR,
sizeof(io_range));
if (caller_phys == 0)
return EFAULT;
kernel_phys = vir2phys(&io_range);
phys_copy(caller_phys, kernel_phys, sizeof(io_range));
priv(rp)->s_flags |= CHECK_IO_PORT; /* Check I/O accesses */
i= priv(rp)->s_nr_io_range;
if (i >= NR_IO_RANGE)
return ENOMEM;
priv(rp)->s_io_tab[i].ior_base= io_range.ior_base;
priv(rp)->s_io_tab[i].ior_limit= io_range.ior_limit;
priv(rp)->s_nr_io_range++;
return OK;
case SYS_PRIV_ADD_MEM:
if (RTS_ISSET(rp, NO_PRIV))
return(EPERM);
/* Only system processes get memory resources? */
if (!(priv(rp)->s_flags & SYS_PROC))
return EPERM;
/* Get the memory range */
caller_phys = umap_local(caller_ptr, D, (vir_bytes) m_ptr->CTL_ARG_PTR,
sizeof(mem_range));
if (caller_phys == 0)
return EFAULT;
kernel_phys = vir2phys(&mem_range);
phys_copy(caller_phys, kernel_phys, sizeof(mem_range));
priv(rp)->s_flags |= CHECK_MEM; /* Check I/O accesses */
i= priv(rp)->s_nr_mem_range;
if (i >= NR_MEM_RANGE)
return ENOMEM;
#if 0
priv(rp)->s_mem_tab[i].mr_base= mem_range.mr_base;
priv(rp)->s_mem_tab[i].mr_limit= mem_range.mr_limit;
priv(rp)->s_nr_mem_range++;
#endif
return OK;
case SYS_PRIV_ADD_IRQ:
if (RTS_ISSET(rp, NO_PRIV))
return(EPERM);
/* Only system processes get IRQs? */
if (!(priv(rp)->s_flags & SYS_PROC))
return EPERM;
priv(rp)->s_flags |= CHECK_IRQ; /* Check IRQs */
i= priv(rp)->s_nr_irq;
if (i >= NR_IRQ)
return ENOMEM;
priv(rp)->s_irq_tab[i]= m_ptr->CTL_MM_PRIV;
priv(rp)->s_nr_irq++;
return OK;
default:
kprintf("do_privctl: bad request %d\n", m_ptr->CTL_REQUEST);
return EINVAL;
}
}
#endif /* USE_PRIVCTL */