示例#1
0
/*===========================================================================*
 *				do_privctl				     *
 *===========================================================================*/
PUBLIC int do_privctl(struct proc * caller, message * m_ptr)
{
/* Handle sys_privctl(). Update a process' privileges. If the process is not
 * yet a system process, make sure it gets its own privilege structure.
 */
  struct proc *rp;
  proc_nr_t proc_nr;
  sys_id_t priv_id;
  int ipc_to_m, kcalls;
  int i, r;
  struct io_range io_range;
  struct mem_range mem_range;
  struct priv priv;
  int irq;

  /* 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 RTS_NO_PRIV flag. This flag is set when a privileged process
   * forks. 
   */
  if (! (priv(caller)->s_flags & SYS_PROC)) return(EPERM);
  if(m_ptr->CTL_ENDPT == SELF) proc_nr = _ENDPOINT_P(caller->p_endpoint);
  else if(!isokendpt(m_ptr->CTL_ENDPT, &proc_nr)) return(EINVAL);
  rp = proc_addr(proc_nr);

  switch(m_ptr->CTL_REQUEST)
  {
  case SYS_PRIV_ALLOW:
	/* Allow process to run. Make sure its privilege structure has already
	 * been set.
	 */
	if (!RTS_ISSET(rp, RTS_NO_PRIV) || priv(rp)->s_proc_nr == NONE) {
		return(EPERM);
	}
	RTS_UNSET(rp, RTS_NO_PRIV);
	return(OK);

  case SYS_PRIV_DISALLOW:
	/* Disallow process from running. */
	if (RTS_ISSET(rp, RTS_NO_PRIV)) return(EPERM);
	RTS_SET(rp, RTS_NO_PRIV);
	return(OK);

  case SYS_PRIV_SET_SYS:
	/* Set a privilege structure of a blocked system process. */
	if (! RTS_ISSET(rp, RTS_NO_PRIV)) return(EPERM);

	/* Check whether a static or dynamic privilege id must be allocated. */
	priv_id = NULL_PRIV_ID;
	if (m_ptr->CTL_ARG_PTR)
	{
		/* Copy privilege structure from caller */
		if((r=data_copy(caller->p_endpoint, (vir_bytes) m_ptr->CTL_ARG_PTR,
			KERNEL, (vir_bytes) &priv, sizeof(priv))) != OK)
			return r;

		/* See if the caller wants to assign a static privilege id. */
		if(!(priv.s_flags & DYN_PRIV_ID)) {
			priv_id = priv.s_id;
		}
	}

	/* Make sure this process has its own privileges structure. This may
	 * fail, since there are only a limited number of system processes.
	 * Then copy privileges from the caller and restore some defaults.
	 */
	if ((i=get_priv(rp, priv_id)) != OK)
	{
		printf("do_privctl: unable to allocate priv_id %d: %d\n",
			priv_id, i);
		return(i);
	}
	priv_id = priv(rp)->s_id;		/* backup privilege id */
	*priv(rp) = *priv(caller);		/* 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< NR_SYS_CHUNKS; 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 */
	reset_timer(&priv(rp)->s_alarm_timer);		/* - alarm */
	priv(rp)->s_asyntab= -1;			/* - asynsends */
	priv(rp)->s_asynsize= 0;

	/* Set defaults for privilege bitmaps. */
	priv(rp)->s_flags= DEF_SYS_F;           /* privilege flags */
	priv(rp)->s_trap_mask= DEF_SYS_T;       /* allowed traps */
	ipc_to_m = DEF_SYS_M;                   /* allowed targets */
	kcalls = DEF_SYS_KC;                    /* allowed kernel calls */
	for(i = 0; i < SYS_CALL_MASK_SIZE; i++) {
		priv(rp)->s_k_call_mask[i] = (kcalls == NO_C ? 0 : (~0));
	}

	/* Set the default signal manager. */
	priv(rp)->s_sig_mgr = DEF_SYS_SM;

	/* Set defaults for resources: 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;

	/* Override defaults if the caller has supplied a privilege structure. */
	if (m_ptr->CTL_ARG_PTR)
	{
		/* Copy s_flags and signal manager. */
		priv(rp)->s_flags = priv.s_flags;
		priv(rp)->s_sig_mgr = priv.s_sig_mgr;

		/* Copy IRQs */
		if(priv.s_flags & CHECK_IRQ) {
			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
				printf("do_privctl: adding IRQ %d for %d\n",
					priv(rp)->s_irq_tab[i], rp->p_endpoint);
#endif
			}
		}

		/* Copy I/O ranges */
		if(priv.s_flags & CHECK_IO_PORT) {
			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
				printf("do_privctl: adding I/O range [%x..%x] for %d\n",
					priv(rp)->s_io_tab[i].ior_base,
					priv(rp)->s_io_tab[i].ior_limit,
					rp->p_endpoint);
#endif
			}
		}

		/* Copy memory ranges */
		if(priv.s_flags & CHECK_MEM) {
			if (priv.s_nr_mem_range < 0 || priv.s_nr_mem_range > NR_MEM_RANGE)
				return EINVAL;
			priv(rp)->s_nr_mem_range= priv.s_nr_mem_range;
			for (i= 0; i<priv.s_nr_mem_range; i++)
			{
				priv(rp)->s_mem_tab[i]= priv.s_mem_tab[i];
#if 0
				printf("do_privctl: adding mem range [%x..%x] for %d\n",
					priv(rp)->s_mem_tab[i].mr_base,
					priv(rp)->s_mem_tab[i].mr_limit,
					rp->p_endpoint);
#endif
			}
		}

		/* Copy trap mask. */
		priv(rp)->s_trap_mask = priv.s_trap_mask;

		/* Copy target mask. */
		memcpy(&ipc_to_m, &priv.s_ipc_to, sizeof(ipc_to_m));

		/* Copy kernel call mask. */
		memcpy(priv(rp)->s_k_call_mask, priv.s_k_call_mask,
			sizeof(priv(rp)->s_k_call_mask));
	}

	/* Fill in target mask. */
	for (i=0; i < NR_SYS_PROCS; i++) {
		if (ipc_to_m & (1 << i))
			set_sendto_bit(rp, i);
		else
			unset_sendto_bit(rp, i);
	}

	return(OK);

  case SYS_PRIV_SET_USER:
	/* Set a privilege structure of a blocked user process. */
	if (!RTS_ISSET(rp, RTS_NO_PRIV)) return(EPERM);

	/* Link the process to the privilege structure of the root user
	 * process all the user processes share.
	 */
	priv(rp) = priv_addr(USER_PRIV_ID);

	return(OK);

  case SYS_PRIV_ADD_IO:
	if (RTS_ISSET(rp, RTS_NO_PRIV))
		return(EPERM);

	/* Only system processes get I/O resources? */
	if (!(priv(rp)->s_flags & SYS_PROC))
		return EPERM;

#if 0 /* XXX -- do we need a call for this? */
	if (strcmp(rp->p_name, "fxp") == 0 ||
		strcmp(rp->p_name, "rtl8139") == 0)
	{
		printf("setting ipc_stats_target to %d\n", rp->p_endpoint);
		ipc_stats_target= rp->p_endpoint;
	}
#endif

	/* Get the I/O range */
	data_copy(caller->p_endpoint, (vir_bytes) m_ptr->CTL_ARG_PTR,
		KERNEL, (vir_bytes) &io_range, 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) {
		printf("do_privctl: %d already has %d i/o ranges.\n",
			rp->p_endpoint, i);
		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, RTS_NO_PRIV))
		return(EPERM);

	/* Only system processes get memory resources? */
	if (!(priv(rp)->s_flags & SYS_PROC))
		return EPERM;

	/* Get the memory range */
	if((r=data_copy(caller->p_endpoint, (vir_bytes) m_ptr->CTL_ARG_PTR,
		KERNEL, (vir_bytes) &mem_range, sizeof(mem_range))) != OK)
		return r;
	priv(rp)->s_flags |= CHECK_MEM;	/* Check memory mappings */
	i= priv(rp)->s_nr_mem_range;
	if (i >= NR_MEM_RANGE) {
		printf("do_privctl: %d already has %d mem ranges.\n",
			rp->p_endpoint, i);
		return ENOMEM;
	}

	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++;

	return OK;

  case SYS_PRIV_ADD_IRQ:
	if (RTS_ISSET(rp, RTS_NO_PRIV))
		return(EPERM);

	/* Only system processes get IRQs? */
	if (!(priv(rp)->s_flags & SYS_PROC))
		return EPERM;

	data_copy(caller->p_endpoint, (vir_bytes) m_ptr->CTL_ARG_PTR,
		KERNEL, (vir_bytes) &irq, sizeof(irq));
	priv(rp)->s_flags |= CHECK_IRQ;	/* Check IRQs */

	i= priv(rp)->s_nr_irq;
	if (i >= NR_IRQ) {
		printf("do_privctl: %d already has %d irq's.\n",
			rp->p_endpoint, i);
		return ENOMEM;
	}
	priv(rp)->s_irq_tab[i]= irq;
	priv(rp)->s_nr_irq++;

	return OK;
  case SYS_PRIV_QUERY_MEM:
  {
	phys_bytes addr, limit;
  	struct priv *sp;
	/* See if a certain process is allowed to map in certain physical
	 * memory.
	 */
	addr = (phys_bytes) m_ptr->CTL_PHYSSTART;
	limit = addr + (phys_bytes) m_ptr->CTL_PHYSLEN - 1;
	if(limit < addr)
		return EPERM;
	if(!(sp = priv(rp)))
		return EPERM;
	if (!(sp->s_flags & SYS_PROC))
		return EPERM;
	for(i = 0; i < sp->s_nr_mem_range; i++) {
		if(addr >= sp->s_mem_tab[i].mr_base &&
		   limit <= sp->s_mem_tab[i].mr_limit)
			return OK;
	}
	return EPERM;
  }
  default:
	printf("do_privctl: bad request %d\n", m_ptr->CTL_REQUEST);
	return EINVAL;
  }
}
示例#2
0
void main(void)
{
/* Start the ball rolling. */
	struct boot_image *ip;		/* boot image pointer */
	register struct proc *rp;	/* process pointer */
	register struct priv *sp;	/* privilege structure pointer */
	register int i, j;
	int hdrindex;			/* index to array of a.out headers */
	phys_clicks text_base;
	vir_clicks text_clicks, data_clicks, st_clicks;
	reg_t ktsb;			/* kernel task stack base */
	struct exec *e_hdr = 0;		/* for a copy of an a.out header */

	/* Global value to test segment sanity. */
	magictest = MAGICTEST;

	/* Clear the process table. Anounce each slot as empty and set up mappings 
	 * for proc_addr() and proc_nr() macros. Do the same for the table with 
	 * privilege structures for the system processes.
	 */
	for (rp = BEG_PROC_ADDR, i = -NR_TASKS; rp < END_PROC_ADDR; ++rp, ++i) {
  	rp->p_rts_flags = RTS_SLOT_FREE;		/* initialize free slot */
#ifdef CONFIG_DEBUG_KERNEL_SCHED_CHECK
		rp->p_magic = PMAGIC;
#endif
		rp->p_nr = i;				/* proc number from ptr */
		rp->p_endpoint = _ENDPOINT(0, rp->p_nr); /* generation no. 0 */
	}

	for (sp = BEG_PRIV_ADDR, i = 0; sp < END_PRIV_ADDR; ++sp, ++i) {
		sp->s_proc_nr = ENDPT_NONE;			/* initialize as free */
		sp->s_id = i;				/* priv structure index */
		ppriv_addr[i] = sp;			/* priv ptr from number */
	}

	/* Set up proc table entries for processes in boot image.  The stacks of the
	 * kernel tasks are initialized to an array in data space.  The stacks
	 * of the servers have been added to the data segment by the monitor, so
	 * the stack pointer is set to the end of the data segment.  All the
	 * processes are in low memory on the 8086.  On the 386 only the kernel
	 * is in low memory, the rest is loaded in extended memory.
	 */

	/* Task stacks. */
	ktsb = (reg_t) t_stack;

	for (i=0; i < NR_BOOT_PROCS; ++i) {
		int schedulable_proc, proc_nr;
		int ipc_to_m, kcalls;

		ip = &image[i];				/* process' attributes */
		rp = proc_addr(ip->proc_nr);		/* get process pointer */
		ip->endpoint = rp->p_endpoint;		/* ipc endpoint */
		rp->p_max_priority = ip->priority;	/* max scheduling priority */
		rp->p_priority = ip->priority;		/* current priority */
		rp->p_quantum_size = ip->quantum;	/* quantum size in ticks */
		rp->p_ticks_left = ip->quantum;		/* current credit */

		strncpy(rp->p_name, ip->proc_name, P_NAME_LEN); /* set process name */
		/* See if this process is immediately schedulable.
		 * In that case, set its privileges now and allow it to run.
		 * Only kernel tasks and the root system process get to run immediately.
		 * All the other system processes are inhibited from running by the
		 * RTS_NO_PRIV flag. They can only be scheduled once the root system
		 * process has set their privileges.
		 */
		proc_nr = proc_nr(rp);
		schedulable_proc = (iskerneln(proc_nr) || isrootsysn(proc_nr));
		if(schedulable_proc) {
			/* Assign privilege structure. Force a static privilege id. */
			(void) get_priv(rp, static_priv_id(proc_nr));

			/* Priviliges for kernel tasks. */
			if(iskerneln(proc_nr)) {
				/* Privilege flags. */
				priv(rp)->s_flags = (proc_nr == IDLE ? IDL_F : TSK_F);
				/* Allowed traps. */
				priv(rp)->s_trap_mask = (proc_nr == CLOCK
					|| proc_nr == SYSTEM  ? CSK_T : TSK_T);
				ipc_to_m = TSK_M;                  /* allowed targets */
				kcalls = TSK_KC;                   /* allowed kernel calls */
			} else if(isrootsysn(proc_nr)) {
			/* Priviliges for the root system process. */
				priv(rp)->s_flags= RSYS_F;         /* privilege flags */
				priv(rp)->s_trap_mask= RSYS_T;     /* allowed traps */
				ipc_to_m = RSYS_M;                 /* allowed targets */
				kcalls = RSYS_KC;                  /* allowed kernel calls */
			}

			/* Fill in target mask. */
			for (j=0; j < NR_SYS_PROCS; j++) {
				if (ipc_to_m & (1 << j))
					set_sendto_bit(rp, j);
				else
					unset_sendto_bit(rp, j);
			}

			/* Fill in kernel call mask. */
			for(j = 0; j < CALL_MASK_SIZE; j++) {
				priv(rp)->s_k_call_mask[j] = (kcalls == NO_C ? 0 : (~0));
			}
		} else {
			/*Don't let the process run for now. */
			RTS_SET(rp, RTS_NO_PRIV);
		}

		if (iskerneln(proc_nr)) {               /* part of the kernel? */
			if (ip->stksize > 0) {		/* HARDWARE stack size is 0 */
				rp->p_priv->s_stack_guard = (reg_t *) ktsb;
				*rp->p_priv->s_stack_guard = STACK_GUARD;
			}

			ktsb += ip->stksize;	/* point to high end of stack */
			rp->p_reg.sp = ktsb;	/* this task's initial stack ptr */
			hdrindex = 0;		/* all use the first a.out header */
		} else {
			hdrindex = 1 + i-NR_TASKS;	/* system/user processes */
		}

		/* Architecture-specific way to find out aout header of this
		 * boot process.
		 */
		e_hdr = arch_get_aout_header(hdrindex);

		/* Convert addresses to clicks and build process memory map */
		text_base = e_hdr->a_syms >> CLICK_SHIFT;
		st_clicks= (e_hdr->a_total + CLICK_SIZE-1) >> CLICK_SHIFT;
		data_clicks = (e_hdr->a_text + e_hdr->a_data + e_hdr->a_bss + CLICK_SIZE-1) >> CLICK_SHIFT;
		text_clicks = 0;

		rp->p_memmap[T].mem_phys = text_base;
		rp->p_memmap[T].mem_len  = text_clicks;
		rp->p_memmap[D].mem_phys = text_base + text_clicks;
		rp->p_memmap[D].mem_len  = data_clicks;
		rp->p_memmap[S].mem_phys = text_base + text_clicks + st_clicks;
		rp->p_memmap[S].mem_vir  = st_clicks;
		rp->p_memmap[S].mem_len  = 0;

		/* Patch (override) the non-kernel process' entry points in image table. The
		 * image table is located in kernel/kernel_syms.c. The kernel processes like
		 * IDLE, SYSTEM, CLOCK, HARDWARE are not changed because they are part of kernel
		 * and the entry points are set at compilation time. In case of IDLE or HARDWARE
		 * the entry point can be ignored becasue they never run (set RTS_PROC_STOP).
		 */
		if (!iskerneln(proc_nr(rp)))
			ip->initial_pc = (task_t*)e_hdr->a_entry;

		/* Set initial register values.  The processor status word for tasks 
		 * is different from that of other processes because tasks can
		 * access I/O; this is not allowed to less-privileged processes 
		 */
		rp->p_reg.pc = (reg_t) ip->initial_pc;
		rp->p_reg.psw = (iskerneln(proc_nr)) ? INIT_TASK_PSW : INIT_PSW;

		/* Initialize the server stack pointer. Take it down one word
		 * to give crtso.s something to use as "argc","argv" and "envp".
		 */
		if (isusern(proc_nr)) {		/* user-space process? */
			rp->p_reg.sp = (rp->p_memmap[S].mem_vir + rp->p_memmap[S].mem_len)
					<< CLICK_SHIFT;
			rp->p_reg.sp -= 3*sizeof(reg_t);
		}

		/* scheduling functions depend on proc_ptr pointing somewhere. */
		if(!proc_ptr)
			proc_ptr = rp;

		/* If this process has its own page table, VM will set the
		 * PT up and manage it. VM will signal the kernel when it has
		 * done this; until then, don't let it run.
		 */
		if(ip->flags & PROC_FULLVM)
			RTS_SET(rp, RTS_VMINHIBIT);

		/* IDLE & HARDWARE task is never put on a run queue as it is
		 * never ready to run.
		 */
		if (rp->p_nr == HARDWARE)
			RTS_SET(rp, RTS_PROC_STOP);

		if (rp->p_nr == IDLE)
			RTS_SET(rp, RTS_PROC_STOP);

		RTS_UNSET(rp, RTS_SLOT_FREE); /* remove RTS_SLOT_FREE and schedule */
		alloc_segments(rp);
	} /* for */

	/* Architecture-dependent initialization. */
	arch_init();

#ifdef CONFIG_DEBUG_KERNEL_STATS_PROFILE
	sprofiling = 0;      /* we're not profiling until instructed to */
#endif
	cprof_procs_no = 0;  /* init nr of hash table slots used */

#ifdef CONFIG_IDLE_TSC
	idle_tsc = cvu64(0);
#endif

	vm_running = 0;
	krandom.random_sources = RANDOM_SOURCES;
	krandom.random_elements = RANDOM_ELEMENTS;

	/* Nucleos is now ready. All boot image processes are on the ready queue.
	 * Return to the assembly code to start running the current process. 
	 */
	bill_ptr = proc_addr(IDLE);		/* it has to point somewhere */
	announce();				/* print Nucleos startup banner */

	/*
	 * enable timer interrupts and clock task on the boot CPU
	 */
	if (boot_cpu_init_timer(system_hz)) {
		kernel_panic("FATAL : failed to initialize timer interrupts, "
			    "cannot continue without any clock source!",
			    NO_NUM);
	}

	/* Warnings for sanity checks that take time. These warnings are printed
	 * so it's a clear warning no full release should be done with them
	 * enabled.
	 */
#ifdef CONFIG_DEBUG_KERNEL_SCHED_CHECK
	FIXME("CONFIG_DEBUG_KERNEL_SCHED_CHECK enabled");
#endif

#ifdef CONFIG_DEBUG_KERNEL_VMASSERT
	FIXME("CONFIG_DEBUG_KERNEL_VMASSERT enabled");
#endif

#ifdef CONFIG_DEBUG_PROC_CHECK
	FIXME("PROC check enabled");
#endif

	restart();
}