minix/kernel/system/do_privctl.c
Ben Gras d69cc76e03 rename struct mem_range to minix_mem_range
. avoid a name clash with gdb
2012-08-15 15:17:25 +02:00

410 lines
11 KiB
C

/* The kernel call implemented in this file:
* m_type: SYS_PRIVCTL
*
* The parameters for this kernel call are:
* m2_i1: CTL_ENDPT (process endpoint of target)
* m2_i2: CTL_REQUEST (privilege control request)
* m2_p1: CTL_ARG_PTR (pointer to request data)
*/
#include "kernel/system.h"
#include "kernel/ipc.h"
#include <signal.h>
#include <string.h>
#include <minix/endpoint.h>
#if USE_PRIVCTL
#define PRIV_DEBUG 0
static int update_priv(struct proc *rp, struct priv *priv);
/*===========================================================================*
* do_privctl *
*===========================================================================*/
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;
sys_map_t map;
int ipc_to_m, kcalls;
int i, r;
struct io_range io_range;
struct minix_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) okendpt(caller->p_endpoint, &proc_nr);
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_YIELD:
/* Allow process to run and suspend the caller. */
if (!RTS_ISSET(rp, RTS_NO_PRIV) || priv(rp)->s_proc_nr == NONE) {
return(EPERM);
}
RTS_SET(caller, RTS_NO_PRIV);
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 */
(void) 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= DSRV_F; /* privilege flags */
priv(rp)->s_trap_mask= DSRV_T; /* allowed traps */
memset(&map, 0, sizeof(map));
ipc_to_m = DSRV_M; /* allowed targets */
if (ipc_to_m == ALL_M) {
for (i = 0; i < NR_SYS_PROCS; i++)
set_sys_bit(map, i);
}
fill_sendto_mask(rp, &map);
kcalls = DSRV_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 managers. */
priv(rp)->s_sig_mgr = DSRV_SM;
priv(rp)->s_bak_sig_mgr = NONE;
/* 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)
{
if((r = update_priv(rp, &priv)) != OK) {
return r;
}
}
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 */
for (i = 0; i < priv(rp)->s_nr_io_range; i++) {
if (priv(rp)->s_io_tab[i].ior_base == io_range.ior_base &&
priv(rp)->s_io_tab[i].ior_limit == io_range.ior_limit)
return OK;
}
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 */
/* When restarting a driver, check if it already has the premission */
for (i = 0; i < priv(rp)->s_nr_mem_range; i++) {
if (priv(rp)->s_mem_tab[i].mr_base == mem_range.mr_base &&
priv(rp)->s_mem_tab[i].mr_limit == mem_range.mr_limit)
return OK;
}
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 */
/* When restarting a driver, check if it already has the premission */
for (i = 0; i < priv(rp)->s_nr_irq; i++) {
if (priv(rp)->s_irq_tab[i] == irq)
return OK;
}
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;
}
case SYS_PRIV_UPDATE_SYS:
/* Update the privilege structure of a system process. */
if(!m_ptr->CTL_ARG_PTR) return EINVAL;
/* 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;
/* Override settings in existing privilege structure. */
if((r = update_priv(rp, &priv)) != OK) {
return r;
}
return(OK);
default:
printf("do_privctl: bad request %d\n", m_ptr->CTL_REQUEST);
return EINVAL;
}
}
/*===========================================================================*
* update_priv *
*===========================================================================*/
static int update_priv(struct proc *rp, struct priv *priv)
{
/* Update the privilege structure of a given process. */
int i;
/* Copy s_flags and signal managers. */
priv(rp)->s_flags = priv->s_flags;
priv(rp)->s_sig_mgr = priv->s_sig_mgr;
priv(rp)->s_bak_sig_mgr = priv->s_bak_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 PRIV_DEBUG
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 PRIV_DEBUG
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 PRIV_DEBUG
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. */
#if PRIV_DEBUG
printf("do_privctl: Setting ipc target mask for %d:");
for (i=0; i < NR_SYS_PROCS; i += BITCHUNK_BITS) {
printf(" %08x", get_sys_bits(priv->s_ipc_to, i));
}
printf("\n");
#endif
fill_sendto_mask(rp, &priv->s_ipc_to);
#if PRIV_DEBUG
printf("do_privctl: Set ipc target mask for %d:");
for (i=0; i < NR_SYS_PROCS; i += BITCHUNK_BITS) {
printf(" %08x", get_sys_bits(priv(rp)->s_ipc_to, i));
}
printf("\n");
#endif
/* Copy kernel call mask. */
memcpy(priv(rp)->s_k_call_mask, priv->s_k_call_mask,
sizeof(priv(rp)->s_k_call_mask));
return OK;
}
#endif /* USE_PRIVCTL */