minix3/servers/pm/misc.c

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2020-02-21 00:59:27 +05:30
/* Miscellaneous system calls. Author: Kees J. Bot
* 31 Mar 2000
* The entry points into this file are:
* do_reboot: kill all processes, then reboot system
* do_getsysinfo: request copy of PM data structure (Jorrit N. Herder)
* do_getprocnr: lookup endpoint by process ID
* do_getepinfo: get the pid/uid/gid of a process given its endpoint
* do_getsetpriority: get/set process priority
* do_svrctl: process manager control
*/
#include "pm.h"
#include <minix/callnr.h>
#include <signal.h>
#include <sys/svrctl.h>
#include <sys/reboot.h>
#include <sys/resource.h>
#include <sys/utsname.h>
#include <minix/com.h>
#include <minix/config.h>
#include <minix/sysinfo.h>
#include <minix/type.h>
#include <minix/ds.h>
#include <machine/archtypes.h>
#include <lib.h>
#include <assert.h>
#include "mproc.h"
#include "kernel/proc.h"
struct utsname uts_val = {
OS_NAME, /* system name */
"noname", /* node/network name */
OS_RELEASE, /* O.S. release (e.g. 3.3.0) */
OS_VERSION, /* O.S. version (e.g. Minix 3.3.0 (GENERIC)) */
#if defined(__i386__)
"i386", /* machine (cpu) type */
"i386", /* architecture */
#elif defined(__arm__)
"arm", /* machine (cpu) type */
"arm", /* architecture */
#else
#error /* oops, no 'uname -mk' */
#endif
};
static char *uts_tbl[] = {
uts_val.arch,
NULL, /* No kernel architecture */
uts_val.machine,
NULL, /* No hostname */
uts_val.nodename,
uts_val.release,
uts_val.version,
uts_val.sysname,
NULL, /* No bus */ /* No bus */
};
#if ENABLE_SYSCALL_STATS
unsigned long calls_stats[NR_PM_CALLS];
#endif
/*===========================================================================*
* do_sysuname *
*===========================================================================*/
int do_sysuname()
{
/* Set or get uname strings. */
int r;
size_t n;
char *string;
#if 0 /* for updates */
char tmp[sizeof(uts_val.nodename)];
static short sizes[] = {
0, /* arch, (0 = read-only) */
0, /* kernel */
0, /* machine */
0, /* sizeof(uts_val.hostname), */
sizeof(uts_val.nodename),
0, /* release */
0, /* version */
0, /* sysname */
};
#endif
if (m_in.m_lc_pm_sysuname.field >= _UTS_MAX) return(EINVAL);
string = uts_tbl[m_in.m_lc_pm_sysuname.field];
if (string == NULL)
return EINVAL; /* Unsupported field */
switch (m_in.m_lc_pm_sysuname.req) {
case _UTS_GET:
/* Copy an uname string to the user. */
n = strlen(string) + 1;
if (n > m_in.m_lc_pm_sysuname.len) n = m_in.m_lc_pm_sysuname.len;
r = sys_datacopy(SELF, (vir_bytes)string, mp->mp_endpoint,
m_in.m_lc_pm_sysuname.value, (phys_bytes)n);
if (r < 0) return(r);
break;
#if 0 /* no updates yet */
case _UTS_SET:
/* Set an uname string, needs root power. */
len = sizes[m_in.m_lc_pm_sysuname.field];
if (mp->mp_effuid != 0 || len == 0) return(EPERM);
n = len < m_in.m_lc_pm_sysuname.len ? len : m_in.m_lc_pm_sysuname.len;
if (n <= 0) return(EINVAL);
r = sys_datacopy(mp->mp_endpoint, m_in.m_lc_pm_sysuname.value, SELF,
(phys_bytes)tmp, (phys_bytes)n);
if (r < 0) return(r);
tmp[n-1] = 0;
strcpy(string, tmp);
break;
#endif
default:
return(EINVAL);
}
/* Return the number of bytes moved. */
return(n);
}
/*===========================================================================*
* do_getsysinfo *
*===========================================================================*/
int do_getsysinfo()
{
vir_bytes src_addr, dst_addr;
size_t len;
/* This call leaks important information. In the future, requests from
* non-system processes should be denied.
*/
if (mp->mp_effuid != 0)
{
printf("PM: unauthorized call of do_getsysinfo by proc %d '%s'\n",
mp->mp_endpoint, mp->mp_name);
sys_diagctl_stacktrace(mp->mp_endpoint);
return EPERM;
}
switch(m_in.m_lsys_getsysinfo.what) {
case SI_PROC_TAB: /* copy entire process table */
src_addr = (vir_bytes) mproc;
len = sizeof(struct mproc) * NR_PROCS;
break;
#if ENABLE_SYSCALL_STATS
case SI_CALL_STATS:
src_addr = (vir_bytes) calls_stats;
len = sizeof(calls_stats);
break;
#endif
default:
return(EINVAL);
}
if (len != m_in.m_lsys_getsysinfo.size)
return(EINVAL);
dst_addr = m_in.m_lsys_getsysinfo.where;
return sys_datacopy(SELF, src_addr, who_e, dst_addr, len);
}
/*===========================================================================*
* do_getprocnr *
*===========================================================================*/
int do_getprocnr(void)
{
register struct mproc *rmp;
/* This check should be replaced by per-call ACL checks. */
if (who_e != RS_PROC_NR) {
printf("PM: unauthorized call of do_getprocnr by %d\n", who_e);
return EPERM;
}
if ((rmp = find_proc(m_in.m_lsys_pm_getprocnr.pid)) == NULL)
return(ESRCH);
mp->mp_reply.m_pm_lsys_getprocnr.endpt = rmp->mp_endpoint;
return(OK);
}
/*===========================================================================*
* do_getepinfo *
*===========================================================================*/
int do_getepinfo(void)
{
struct mproc *rmp;
endpoint_t ep;
int slot;
ep = m_in.m_lsys_pm_getepinfo.endpt;
if (pm_isokendpt(ep, &slot) != OK)
return(ESRCH);
rmp = &mproc[slot];
mp->mp_reply.m_pm_lsys_getepinfo.uid = rmp->mp_effuid;
mp->mp_reply.m_pm_lsys_getepinfo.gid = rmp->mp_effgid;
return(rmp->mp_pid);
}
/*===========================================================================*
* do_reboot *
*===========================================================================*/
int do_reboot()
{
message m;
/* Check permission to abort the system. */
if (mp->mp_effuid != SUPER_USER) return(EPERM);
/* See how the system should be aborted. */
abort_flag = m_in.m_lc_pm_reboot.how;
/* notify readclock (some arm systems power off via RTC alarms) */
if (abort_flag & RB_POWERDOWN) {
endpoint_t readclock_ep;
if (ds_retrieve_label_endpt("readclock.drv", &readclock_ep) == OK) {
message m; /* no params to set, nothing we can do if it fails */
_taskcall(readclock_ep, RTCDEV_PWR_OFF, &m);
}
}
/* Order matters here. When VFS is told to reboot, it exits all its
* processes, and then would be confused if they're exited again by
* SIGKILL. So first kill, then reboot.
*/
check_sig(-1, SIGKILL, FALSE /* ksig*/); /* kill all users except init */
sys_stop(INIT_PROC_NR); /* stop init, but keep it around */
/* Tell VFS to reboot */
memset(&m, 0, sizeof(m));
m.m_type = VFS_PM_REBOOT;
tell_vfs(&mproc[VFS_PROC_NR], &m);
return(SUSPEND); /* don't reply to caller */
}
/*===========================================================================*
* do_getsetpriority *
*===========================================================================*/
int do_getsetpriority()
{
int r, arg_which, arg_who, arg_pri;
struct mproc *rmp;
arg_which = m_in.m_lc_pm_priority.which;
arg_who = m_in.m_lc_pm_priority.who;
arg_pri = m_in.m_lc_pm_priority.prio; /* for SETPRIORITY */
/* Code common to GETPRIORITY and SETPRIORITY. */
/* Only support PRIO_PROCESS for now. */
if (arg_which != PRIO_PROCESS)
return(EINVAL);
if (arg_who == 0)
rmp = mp;
else
if ((rmp = find_proc(arg_who)) == NULL)
return(ESRCH);
if (mp->mp_effuid != SUPER_USER &&
mp->mp_effuid != rmp->mp_effuid && mp->mp_effuid != rmp->mp_realuid)
return EPERM;
/* If GET, that's it. */
if (call_nr == PM_GETPRIORITY) {
return(rmp->mp_nice - PRIO_MIN);
}
/* Only root is allowed to reduce the nice level. */
if (rmp->mp_nice > arg_pri && mp->mp_effuid != SUPER_USER)
return(EACCES);
/* We're SET, and it's allowed.
*
* The value passed in is currently between PRIO_MIN and PRIO_MAX.
* We have to scale this between MIN_USER_Q and MAX_USER_Q to match
* the kernel's scheduling queues.
*/
if ((r = sched_nice(rmp, arg_pri)) != OK) {
return r;
}
rmp->mp_nice = arg_pri;
return(OK);
}
/*===========================================================================*
* do_svrctl *
*===========================================================================*/
int do_svrctl()
{
int s, req;
vir_bytes ptr;
#define MAX_LOCAL_PARAMS 2
static struct {
char name[30];
char value[30];
} local_param_overrides[MAX_LOCAL_PARAMS];
static int local_params = 0;
req = m_in.m_lsys_svrctl.request;
ptr = m_in.m_lsys_svrctl.arg;
/* Is the request indeed for the PM? */
if (((req >> 8) & 0xFF) != 'M') return(EINVAL);
/* Control operations local to the PM. */
switch(req) {
case PMSETPARAM:
case PMGETPARAM: {
struct sysgetenv sysgetenv;
char search_key[64];
char *val_start;
size_t val_len;
size_t copy_len;
/* Copy sysgetenv structure to PM. */
if (sys_datacopy(who_e, ptr, SELF, (vir_bytes) &sysgetenv,
sizeof(sysgetenv)) != OK) return(EFAULT);
/* Set a param override? */
if (req == PMSETPARAM) {
if (local_params >= MAX_LOCAL_PARAMS) return ENOSPC;
if (sysgetenv.keylen <= 0
|| sysgetenv.keylen >=
sizeof(local_param_overrides[local_params].name)
|| sysgetenv.vallen <= 0
|| sysgetenv.vallen >=
sizeof(local_param_overrides[local_params].value))
return EINVAL;
if ((s = sys_datacopy(who_e, (vir_bytes) sysgetenv.key,
SELF, (vir_bytes) local_param_overrides[local_params].name,
sysgetenv.keylen)) != OK)
return s;
if ((s = sys_datacopy(who_e, (vir_bytes) sysgetenv.val,
SELF, (vir_bytes) local_param_overrides[local_params].value,
sysgetenv.vallen)) != OK)
return s;
local_param_overrides[local_params].name[sysgetenv.keylen] = '\0';
local_param_overrides[local_params].value[sysgetenv.vallen] = '\0';
local_params++;
return OK;
}
if (sysgetenv.keylen == 0) { /* copy all parameters */
val_start = monitor_params;
val_len = sizeof(monitor_params);
}
else { /* lookup value for key */
int p;
/* Try to get a copy of the requested key. */
if (sysgetenv.keylen > sizeof(search_key)) return(EINVAL);
if ((s = sys_datacopy(who_e, (vir_bytes) sysgetenv.key,
SELF, (vir_bytes) search_key, sysgetenv.keylen)) != OK)
return(s);
/* Make sure key is null-terminated and lookup value.
* First check local overrides.
*/
search_key[sysgetenv.keylen-1]= '\0';
for(p = 0; p < local_params; p++) {
if (!strcmp(search_key, local_param_overrides[p].name)) {
val_start = local_param_overrides[p].value;
break;
}
}
if (p >= local_params && (val_start = find_param(search_key)) == NULL)
return(ESRCH);
val_len = strlen(val_start) + 1;
}
/* See if it fits in the client's buffer. */
if (val_len > sysgetenv.vallen)
return E2BIG;
/* Value found, make the actual copy (as far as possible). */
copy_len = MIN(val_len, sysgetenv.vallen);
if ((s=sys_datacopy(SELF, (vir_bytes) val_start,
who_e, (vir_bytes) sysgetenv.val, copy_len)) != OK)
return(s);
return OK;
}
default:
return(EINVAL);
}
}
/*===========================================================================*
* do_getrusage *
*===========================================================================*/
int do_getrusage()
{
int res = 0;
clock_t user_time = 0;
clock_t sys_time = 0;
struct rusage r_usage;
u64_t usec;
if (m_in.m_lc_pm_rusage.who != RUSAGE_SELF &&
m_in.m_lc_pm_rusage.who != RUSAGE_CHILDREN)
return EINVAL;
if ((res = sys_getrusage(&r_usage, who_e)) < 0)
return res;
if (m_in.m_lc_pm_rusage.who == RUSAGE_CHILDREN) {
usec = mp->mp_child_utime * 1000000 / sys_hz();
r_usage.ru_utime.tv_sec = usec / 1000000;
r_usage.ru_utime.tv_usec = usec % 1000000;
usec = mp->mp_child_stime * 1000000 / sys_hz();
r_usage.ru_stime.tv_sec = usec / 1000000;
r_usage.ru_stime.tv_usec = usec % 1000000;
}
return sys_datacopy(SELF, (vir_bytes)&r_usage, who_e,
m_in.m_lc_pm_rusage.addr, (vir_bytes) sizeof(r_usage));
}